Journal articles on the topic 'Water quality management Victoria Healesville'

The growing recognition of recreational and amenity demands on water systems introduces a multitude of issues, many of them complex, to the established tasks of water quality management and water management generally. Victorian case studies are presented. They (1) illustrate the range and diversity of situations that can arise in managing competition and enhancing compatibility between traditional water supply objectives and recreational demands. (2) Fluctuation of storage levels, essential to storage operations, detract from recreational value. Recreational and tourism demands upon Lake Hume have grown to threaten traditional operating flexibility. (3) Mokoan is another such instance, but with its supply function in a state of flux, Lake Mokoan provides more scope for a shift in the balance. (4) Salinity management has become an issue in the management of lakes and wetlands when water supply interests and environmental/recreation interests respectively have different perspectives on salt disposal. (5) Recreational use of town supply sources has long been a vexed issue, although marked shifts in the attitudues of many supply authorities have occurred in recent years. (6) Eutrophication of lakes and estuaries raises difficult issues of responsibility and scientific uncertainty, and the water management connection may be tenuous but will attract public attention. (7) The water body attributes valued by specialised recreational interests require definition in terms that water managers can deal with using routine techniques of systems analysis and evaluation. (8) The demands of the fish population and anglers introduce a new perspective in river management and perceptions of instream values are changing markedly. (9) Direct costs of recreational services supplied by water authorities are not fully accounted: allocation choices and fiscal incidence will emerge as issues of significance. (10) These case studies raise only a fraction of the total range of matters that will, in the years to come, tax the technology and political skills of governments and management.

In Dolj County there are a number of lakes that are particularly important, because they have a large quantity of water, some of them originating from hydrotechnical accumulations, and other from natural waters. In the present study, it was performed the monitoring of the water quality of the lakes in Dolj County, in the year of 2012, namely: Victoria - Geormane, Bistreţ and Caraula. The ecological conditions of the natural and artificial lakes was established based on the state of acidification, of the oxygen regime (dissolved oxygen, biochemical oxygen demand and chemical oxygen demand), the degree of eutrophication (biogenic substances, phytoplankton biomass and chlorophyll “a”) and also based on transparency. The water samples were taken from three points: tail, middle and upstream of the lake and were analyzed using high performance equipment, namely: pH-meter, spectrophotometer DR 2010, Sechi disc, BOD5 system. In terms of the degree of eutrophication, the water from the studied lakes belongs to the third category of water quality. Geormane is a natural lake which has a very good ecological status, except regarding the eutrophication, which is considerably visible. Bistret lake has a good environmental status and is visible eutrophic. Caraula lake’s water belongs to the third category of water quality, being heavily eutrophic.

Four forest reserves within 50 km of Kampala in Uganda act as a critical buffer to the Lake Victoria watershed and habitat for local populations. Over a 9-month period we capture a pioneering water quality data set that illustrates ecosystem health through the implementation of a water quality index (WQI). The WQI was calculated using field and laboratory data that reflect measured physical and chemical parameters (pH, dissolved oxygen, biological oxygen on demand, nitrates, phosphates, fecal coliform, and temperature turbidity). Overall, the WQI for the four forest reserves reflect poor to medium water quality. Results compared with US Environmental Protection Agency and World Health Organization drinking water standards indicate varying levels of contamination at most sites and all designated drinking water sources, with signatures of elevated nitrates, phosphates, and/or fecal coliforms. As critical health problems are known to arise with elevated exposure to contaminants in drinking water, this data set can be used to communicate necessary improvements within the watershed.

Environmental water quality issues have dominated global discourse and studies over the past five decades. Significant parameters of environmental water quality include changes in biological and physical parameters. Some of the biological parameters of significance include occurrence of enteric viruses. Enteric viruses can affect both human and animal’s health by causing diseases such as gastrointestinal and respiratory infections. In this study, the relationship between the occurrence of enteric viruses with reference to adenoviruses and enteroviruses and the physical water quality characteristics was assessed from water samples collected from Lake Victoria (LV) in Kenya. In order to understand the dynamics of season driven enteric viruses’ contamination of the lake waters, we additionally analysed seasonal behavior of the lake’s catchment area in terms of rainfall effects. Physical quality parameters were measured on-site while viral analysis was carried out by molecular methods using the nested polymerase chain reaction (nPCR). From 216 samples that were analysed for viral contamination, enteric viral genomes were discovered in 18 (8.3%) of the samples. Out of half of the samples (108) collected during the rainy season, enteric viral genomes were detected in 9.26% (10) while 8 (7.41%) samples tested positive from the other half of the samples (108) collected during the dry season. There was, however, no significant correlation noted between the physical water quality characteristics and the enteric viruses’ occurrence. Neither wet season nor dry season was significantly associated with the prevalence of the viruses. In Lake Victoria waters, most of the samples had an average of physical water quality parameters that were within the range accepted by the World Health Organization (WHO) for surface waters with exemption of turbidity which was above the recommended 5 NTU as recorded from some sampling sites. Continuous and long-term surveillance of the lake water to accurately monitor the contaminants and possible correlation between chemical, physical, and biological characteristics is recommended. This would be important in continuous understanding of the hydrological characteristics changes of the lake for proper management of its quality with reference to the WHO standards. A multiple varied-sampling approach in different geographical regions during different seasons is recommended to establish the geographical distribution and relatedness to seasonal distribution patterns of the viruses. The data generated from this study will be useful in providing a basis for assessment of seasonally driven fecal pollution load of the lake and enteric virus contamination for proper management of the sanitary situation around the lake.

In early 2003, after a prolonged drought period, extensive bushfires occurred in the east of Victoria affecting 1.5 million hectares of land. At the time, smoke and ash from bushfires, settling on roofs, contained pollutants that could potentially contaminate rainwater collected and stored in tanks for domestic use. The major concerns include polycyclic aromatic hydrocarbons (PAHs) from incomplete combustion of organic matter and arsenic from burnt copper chrome arsenate (CCA) treated wood. An increase in microbial contamination through altered nutrient levels was also hypothesised. A pilot study of 49 rainwater tank owners was undertaken in north-east Victoria. A rainwater tank sample was taken and analysed for a variety of parameters including organic compounds, microbiological indicators, metals, nutrients and physico-chemical parameters. A survey was administered concurrently. A number of results were outside the Australian Drinking Water Guideline (ADWG) values for metals and microbiological indicator organisms, but not for any tested organic compounds. PAHs and arsenic are unlikely to be elevated in rainwater tanks as a result of bushfires, but cadmium may be of concern.

Murchison Bay in Lake Victoria is the main water source for Kampala City (Uganda) but is also the recipient for the wastewater discharged from the city. The objective of this paper is to trace the main landuse-based pollution sources within Kampala City borders and around Murchison Bay as a means to develop methods and systems to protect and preserve the aquatic environment and, from the lessons learned, to highlight what is considered to be an appropriate and sustainable approach for Uganda. This paper shows that Uganda needs to set realistic local standards, offer affordable services, set time frameworks, streamline politics, nurture and develop institutions, divide institutional responsibilities, educate her people and learn from the success stories to reverse the negative impacts on the water quality in Murchison Bay.

River Nzoia is the largest river draining into the Kenyan portion of Lake Victoria. This river receives both point sources of pollution from industrial and municipal wastes, and non-point sources from agricultural runoff in the catchment. The objective of this study was to simulate dissolved oxygen (DO) and biochemical oxygen demand (BOD) of the middle section of River Nzoia using MIKE 11 model. The model was calibrated using discharge and water quality data for 2009 and validated with March–April 2013 data. The model performance was good with coefficient of determination (R2) values of between 0.845 and 0.995, Nash–Sutcliffe efficiency values of between 0.748 and 0.993 and percent bias of less than 10 for both calibration and validation of electrical conductivity (EC), DO and BOD. EC and BOD values were lower for April compared to March which could be attributed to dilution during high flows. DO values were above the recommended minimum level of 4 mg/l in all the sections of the river in the wet period but some sections had lower than 4 mg/l during low flow period. The government agencies such as Water Resources Management Authority and National Environment Management Authority should enforce the effluent standards to ensure that industries and wastewater treatment plants adhere to the maximum allowable limit for BOD and also improve their treatment efficiencies of wastewater plants so as to improve the quality of River Nzoia which is important in the overall management of the Lake Victoria basin.

This study, conducted in Nyanza Gulf of Lake Victoria, assessed ecological succession and dynamic status of water hyacinth. Results show that water hyacinth is the genesis of macrophyte succession. On establishment, water hyacinth mats are first invaded by native emergent macrophytes,Ipomoea aquaticaForsk., andEnydra fluctuansLour., during early stages of succession. This is followed by hippo grassVossia cuspidata(Roxb.) Griff. in mid- and late stages whose population peaks during climax stages of succession with concomitant decrease in water hyacinth biomass. Hippo grass depends on water hyacinth for buoyancy, anchorage, and nutrients. The study concludes that macrophyte succession alters aquatic biodiversity and that, since water hyacinth infestation and attendant succession are a symptom of broader watershed management and pollution problems, aquatic macrophyte control should include reduction of nutrient loads and implementing multifaceted approach that incorporates biological agents, mechanical/manual control with utilization of harvested weed for cottage industry by local communities.

Abstract In this paper the environment, climate, vegetation, indigenous and European settlement history, stream flow patterns, water quality and water resources development in western Victoria, Australia are studied. The last part of the paper focuses on the MacKenzie River, a tributary of the Wimmera River located on the northern slopes of the Grampians Ranges in western Victoria, Australia. Water release along the MacKenzie River was regulated to improve water quality, stream condition and river health especially in the downstream reaches. The upstream section tends to receive water most days of the year due to releases to secure the requirements of water supply for the city of Horsham and its recreational and conservation values, which is diverted into Mt Zero Channel. Below this the middle and downstream sections receive a more intermittent supply. Annually, a total of 10,000 dam3 of water is released from Wartook Reservoir into the MacKenzie River. Of this volume, only about 4,000 dam3 was released explicitly for environmental purposes. The remaining 6,000 dam3 was released to meet consumptive demands and to transfer water to downstream reservoirs. The empirical data and models showed the lower reaches of the river to be in poor condition under low flows, but this condition improved under flows of 35 dam3 per day, as indicated. The results are presented to tailor discharge and duration of the river flows by amalgamation of consumptive and environmental flows to improve the condition of the stream, thereby supplementing the flows dedicated to environmental outcomes. Ultimately the findings can be used by management to configure consumptive flows that would enhance the ecological condition of the MacKenzie River.

The Shepparton Irrigation Region Land and Water Salinity Management Plan promotes groundwater pumping and re-use for irrigation where groundwater quality and availability allow dilution with channel water (‘conjunctive water use’) to levels that produce minimal production losses from annual and perennial pastures used widely for dairying. In addition, municipal and industrial waste waters are used on a smaller scale for irrigating pastures (and crops). An upper level of irrigation water salinity (expressed as an electrical conductivity of 0.8 dS/m) is currently recommended in the plan. This recommendation is based on empirical data from experiments on unstocked, perennial pasture collected over 2 decades on red-brown earths in the region. While the strategy has, so far, achieved acceptable control of soil salinity levels, while generally maintaining pasture yields, a concern that ‘conjunctive water use’ may not be sustainable in the long term arises from the sodicity of the groundwater and waste waters. The continual addition of sodium to clay soils, initially low in both sodium and electrolytes (upper 0.5 m depth), risks the soils becoming sodified, with attendant soil physical problems should salts be leached to below threshold electrolyte concentrations, as in winter for example. We show that clay soils supporting pastures in the Shepparton Irrigation Region sodify with time under ‘conjunctive water use’. We review evidence for adverse effects of such sodification on soil physical properties affecting plant productivity and hydrologic processes important in the long-term sustainability of the strategy. On-farm management implications of the strategy are discussed and important issues for research are identified.

Abstract Storm-water management is a common concern in rural catchments where development-related growth causes increases of storm-water flows. Greater magnitude and frequency of storm-water create greater challenges for mitigating storm-water damage and improving water quality. The concept of Blue-Green Infrastructure (BGI) as a solution incorporates a wide range of applicable components with the aim of minimizing the effect of catchment development on flow regimes without changing the watershed morphology. BGI components manage storm-water by decreasing impermeable cover and expanding natural and semi-natural systems to store water or recharge and filter storm-water into the ground. In this paper, guidelines for designing a pond as a component of BGI are provided and, configuration and size of the pond are determined. Moreover, the impacts of the designed pond on storm-water peak flow and quality are assessed for the Tarwin catchment, State of Victoria, Australia. The results indicate that the introduction of the pond would have reduced outfall inflow by 94 % and would have achieved the reduction of 88.3, 75.5 and 50.7 % for total suspended solids, total phosphorus, and total nitrogen respectively, during the extreme weather event in June 2012.

A survey of 170 randomly selected, irrigated, dairy farms in northern Victoria and 9 in southern New South Wales was conducted to examine and benchmark the key factors influencing water-use efficiency. Water-use efficiency was defined as the amount of milk (kg milk fat plus protein) produced from pasture per megalitre of water (irrigation plus effective rainfall). Information on water-use, milk production, supplementary feeding, farm size and type, pasture management, and irrigation layout and management was collected for each farm by personal interview for the 1994–95 and 1995–96 seasons. The farms were ranked in the order of water-use efficiency with the average farm compared with the highest and lowest 10% of farms. The range in water-use efficiency was 25–115 kg milk fat plus protein/ML, with the highest 10% averaging 94 kg/ML and the lowest 10% averaging 35 kg/ML. The large range in water-use efficiency indicated potential for substantial improvement on many farms. The high water-use efficiency farms, when compared with the low group: (i) produced a similar amount of milk from less water (387 v. 572 ML) (P<0.05), less land (48 v. 83 ha) (P< 0.05) and a similar number of cows (152 v. 143 cows); (ii) had higher estimated pasture consumption per hectare (11.5 v. 5.5 t DM/ha) (P<0.01) and per megalitre (1.0 v. 0.5 t DM/ML) (P<0.01); (iii) had higher stocking rates (3.2 v. 1.8 cows/ha) (P<0.01); (iv) used higher rates of nitrogen fertiliser (59 v. 18 kg N/ha.year) (P<0.05) and tended to use more phosphorus fertiliser (64 v. 34 kg P/ha.year) (P<0.10); (v) used similar levels of supplementary feed (872 v. 729 kg concentrates/cow); (vi) had higher milk production per cow (396 v. 277 kg fat plus protein) (P<0.05); and (vii) directed a higher proportion of the estimated energy consumed by cows into milk production (53 v. 46%) (P<0.05). The survey data confirmed that irrigated dairy farm systems are complex and variable. For example, the amount of feed brought in from outside the milking area varied from 0 to 74% of the estimated total energy used by a milking herd. There was a large range in the level of supplement input amongst the farms in the high water-use efficiency group, and in the low water-use efficiency group. This indicates that the management of the farming system has a greater impact on the efficiency of water-use on irrigated dairy farms, than the type of system. The data from the survey provide information for individual farms, a measure of the water-use efficiency of the industry, and an indication of the quality of regional land and water resources.

Waterwatch is a national community-based monitoring network that aims to involve community groups and individuals in the protection and management of waterways. Waterwatch Victoria has the dual objectives of catchment education and water quality monitoring. The educational outcomes are evident, with the Waterwatch programme facilitating over 9,000 students to monitor more than 2,000 sites in waterways in 2000. This paper aims to assess the scientific value of community-collected data, through examining differences between Waterwatch data and professionally collected data. The study looked at all aspects of volunteer data collection, including data confidence protocols, equipment, and data analysis. All professional data was collated by the Victorian Water Quality Monitoring Network (VWQMN). The parameters examined in this study were turbidity, electrical conductivity (EC), pH and total phosphorus. The level of agreement between community-collected data and professional data varied temporally and spatially. Waterwatch data for EC and pH appeared to be very similar to professionally collected data. Equipment used by Waterwatch volunteers for turbidity and total phosphorus appeared to be limited in accuracy to moderate ranges. Overall the VWQMN professionally collected data showed less variance, suggesting greater variability, potentially due to inaccuracies, in volunteer collected data.

Abstract. Our current capacity to model stream water quality is limited – particularly at large spatial scales across multiple catchments. To address this, we developed a Bayesian hierarchical statistical model to simulate the spatiotemporal variability in stream water quality across the state of Victoria, Australia. The model was developed using monthly water quality monitoring data over 21 years and across 102 catchments (which span over 130 000 km2). The modeling focused on six key water quality constituents: total suspended solids (TSS), total phosphorus (TP), filterable reactive phosphorus (FRP), total Kjeldahl nitrogen (TKN), nitrate–nitrite (NOx) and electrical conductivity (EC). The model structure was informed by knowledge of the key factors driving water quality variation, which were identified in two preceding studies using the same dataset. Apart from FRP, which is hardly explained (19.9 %), the model explains 38.2 % (NOx) to 88.6 % (EC) of the total spatiotemporal variability in water quality. Across constituents, the model generally captures over half of the observed spatial variability; the temporal variability remains largely unexplained across all catchments, although long-term trends are well captured. The model is best used to predict proportional changes in water quality on a Box–Cox-transformed scale, but it can have substantial bias if used to predict absolute values for high concentrations. This model can assist catchment management by (1) identifying hot spots and hot moments for waterway pollution; (2) predicting the effects of catchment changes on water quality, e.g., urbanization or forestation; and (3) identifying and explaining major water quality trends and changes. Further model improvements should focus on the following: (1) alternative statistical model structures to improve fitting for truncated data (for constituents where a large amount of data fall below the detection limit); and (2) better representation of nonconservative constituents (e.g., FRP) by accounting for important biogeochemical processes.

Summary. Factors associated with silage quality were investigated on 140 dairy farms in western Victoria. The management factors measured were date of lock up, date cut, length of lock up, duration of wilting, raking and tedding during wilting period, rainfall during wilting period and the type of silage made. Pasture variables measured at harvesting included percentage composition (ryegrass, legume, other grasses and weeds), dry matter of pasture, metabolisable energy, crude protein, neutral detergent fibre and water-soluble carbohydrate of the pasture, and dry matter yield of the pasture. The average lock up time of pasture for silage was mid September, although the range was from late July to early November. The length of lock up varied from 16 to 91 days with a mean value of 49 days and pastures were on average harvested in early November. Ryegrass on average accounted for 61%, legumes and other grasses accounting for a further 15% each and weeds about 5%. The range in quality of pasture at harvesting was highlighted by the range in metabolisable energy (8.9–11.3 MJ/kg DM) and crude protein (10.2–20.4%) values. Wilting times varied from 0.5 to 15 days with the biggest range being observed in pastures used for baled silage. All factors were regressed against final silage metabolisable energy and crude protein. Factors which had the greatest effect on final silage metabolisable energy were date of cutting, length of lock up, type of silage, the interaction between type of silage and length of lock up, length of wilting and mechanical treatment during the wilting period. Final silage crude protein was most strongly associated with date of cutting, crude protein content of the pasture and mechanical treatment during the wilting period. Mechanical treatment during the wilting period had the greatest influence on silage quality. Other options to improve silage quality such as cutting earlier or reducing wilting periods may not be possible or economically viable.

Abstract We present the Multi-metric Index of Biotic Integrity methodological approach that allows for the ranking of major river catchments based on pollution status in the Kenyan portion of Lake Victoria, Africa. The study has a broader applicability to all of Lake Victoria, other African Great Lakes, and all lakes that have riverine discharge. The method presented utilizes water quality and environmental data, local knowledge, and pre-existing literature. The parameters considered were sampled from 2016 to 2018 during the dry season (July sampling) and the wet season (March sampling). Separation power of Mann-Whitney U test (p &lt; 0.05) qualified 11 discriminant metrics for both macroinvertebrate and fish samples into the scoring system of 1, 3 and 5 in the formulation of final Multi-metric Index of Biotic Integrity methodological approach. Rivers in the northern section had lower Multi-metric Index of Biotic Integrity methodological approach scores, as compared to southern counterparts. The Multi-metric Index of Biotic Integrity methodological approach ranking herein was validated by community perceptions on pollution levels. River Nzoia catchment emerged as the most polluted, followed by River Yala, River Kuja, and Sondu-Miriu. Siltation, domestic washing, litter and refuse emerged as the main agents of pollution. Management authorities ought to reinforce a balanced utilization of the vital water resources to minimize future impacts, and promote catchment wide practices that ensure ecological health sustainability of the lake ecosystem.

Abstract Knowledge of the parameters that contribute to water body eutrophication is essential for proper monitoring and management of water quality for human consumption. This study assessed water quality parameters in relation to phycocyanin (PC) as a proxy indicator for harmful algal blooms (HABs). Samples were collected from 23 water sources – lakes, wells, springs and boreholes – in selected villages, for six months. Parameters measured included temperature, pH, redox potential, dissolved oxygen, electrical conductivity, total dissolved solids, nitrate nitrogen, nitrite nitrogen, phosphorus, reactive phosphate and total chlorophyll, which were related to (PC) occurrence. The PC concentration detected in Lake Victoria ranged from 5 to 58.4 μg/l above the WHO alert level and exceeded that in other water sources by almost 30 μg/l (P &lt; 0.001). Univariate relationship between water quality parameters and PC indicates association with temperature, redox potential, total chlorophyll, nitrate nitrogen, nitrite nitrogen, phosphate and reactive phosphorus (P &lt; 0.001). The multivariate model indicates that redox potential, nitrate nitrogen and phosphorus are significant statistically (P &lt; 0.05). A predictive model indicates that nitrate nitrogen and reactive phosphorus contribute significantly to PC occurrence whereby unit (1 mg/l) increases in these parameters increase PC by 9.55 and 4.38 μg/l (P &lt; 0.05) respectively. This study demonstrates that water quality parameters can be used to predict increases in PC and hence as a proxy for HABs. It remains important to be able to classify algal blooms, to understand which species are present and their potential cyanotoxin production.

The Brisbane Ranges include areas of National Park, water catchment and freehold land that have a history of infection with the pathogen P. cinnamomi since the late 1960s. A systematic survey of the small-mammal fauna of the Brisbane Ranges National Park and the Geelong and District Water Board catchments in relation to the pathogen was carried out in 1987. A. stuartii was the only species trapped regularly. The volume of vegetation to a structural level of 60 cm was significantly lower at sites where P. cinnamomi was present. The abundance of A. stuartii was also significantly lower at sites infected with P. cinnamomi, and a significant relationship is shown between the capture rate of A. stuartii and the volume of vegetation present up to 40 cm above ground level. This work indicates a possible association between P. cinnamomi and populations of A. stuartii, and the relationships between the pathogen, habitat quality and small-mammal distribution are discussed. These findings have implications for public land management and management of fauna in areas prone to infection with P. cinnamomi.

Evidence for the decline in native fish communities in the lowland Goulburn Catchment has been based primarily on studies investigating changes to environmental conditions as a result of river regulation. The present study aggregates historical fisheries data to spatially compare native fish communities in different parts of the catchment. Multivariate analyses demonstrate that distinctly different community compositions are found in different parts of the catchment. Eildon Dam, a deep release reservoir, has drastically altered the hydrology and water quality of the upper Goulburn River, and ordination analyses show that this has created both physical and artificial barriers to movement of native fish into the main channel. Concurrently, fisheries data from the upper main channel show the community is highly divergent compared to the remaining catchment. Further downstream, Goulburn Weir creates a barrier to fish movement between Lake Nagambie and the lower Goulburn Catchment, and alters the natural hydrological regime. Similarity Percentage analyses demonstrate that these stressors have facilitated the establishment of alien species, which dominate fish abundance in the upper and lower main channels. The current study emphasises the need to explore alternatives for improving management strategies to rehabilitate fish communities throughout the Goulburn Catchment.

Eleven experimental sites in the Sustainable Grazing Systems (SGS) national experiment were established in the high rainfall zone (HRZ, >600 mm/year) of Western Australia, Victoria and New South Wales to measure components of the water balance, and pathways of water movement, for a range of pastures from 1997 to 2001. The effect of widely spaced river red gums (Eucalyptus camaldulensis) in pasture, and of belts of plantation blue gums (E. globulus), was studied at 2 of the sites. The soil types tested ranged from Kurosols, Chromosols and Sodosols, with different subsoil permeabilities, to Hydrosols and Tenosols. The pasture types tested were kikuyu (Pennisetum clandestinum), phalaris (Phalaris aquatica), redgrass (Bothriochloa macra) and annual ryegrass (Lolium rigidum), with subterranean clover (Trifolium subterraneum) included. Management variables were set stocking v. rotational grazing, adjustable stocking rates, and level of fertiliser input. Soil, pasture and animal measurements were used to set parameters for the biophysical SGS pasture model, which simulated the long-term effects of soil, pasture type, grazing method and management on water use and movement, using as inputs daily weather data for 31 years from selected sites representing a range of climates. Measurements of mean maximum soil water deficit Sm were used to estimate the probability of surplus water occurring in winter, and the average amount of this surplus, which was highest (97–201 mm/year) for pastures in the cooler, winter-rainfall dominant regions of north-east and western Victoria and lowest (3–11 mm/year) in the warmer, lower rainfall regions of the eastern Riverina and Esperance, Western Australia. Kikuyu in Western Australia achieved the largest increase in Sm compared with annual pasture (55–71 mm), while increases due to phalaris were 18–45 mm, and those of native perennials were small and variable. Long-term model simulations suggested rooting depth was crucial in decreasing deep drainage, to about 50 mm/year for kikuyu rooting to 2.5 m, compared with 70–200 mm/year for annuals rooting to only 0.8 m. Plantation blue gums dried the soil profile to 5.25 m by an average of 400 mm more than kikuyu pasture, reducing the probability of winter surplus water to zero, and eliminating drainage below the root zone. Widely spaced river red gums had a much smaller effect on water use, and would need to number at least 14 trees per hectare to achieve extra soil drying of about 50 mm over a catchment. Soil type affected water use primarily through controlling the rooting depth of the vegetation, but it also changed the partitioning of surplus water between runoff and deep drainage. Strongly duplex soils such as Sodosols shed 50% or more surplus water as runoff, which is important for flushing streams, provided the water is of good quality. Grazing method and pasture management had only a marginal effect in increasing water use, but could have a positive effect on farm profitability through increased livestock production per hectare and improved persistence of perennial species.

The lakes of Africa provide outstanding examples of biodiversity. Some hundreds of species of aquatic fauna, especially fishes, have been created through evolution taking place in environments which became isolated from each other. The lakes also provide an outstanding example of the loss of biodiversity: in Lake Victoria at least 200 species of fish have almost certainly become extinct through human activities. These lakes have, since Mankind's origin in Africa, provided high-quality animal protein food and with improved management they could provide much more, which adds greatly to their scientific and economic interest.

Abstract Currently guidelines for disinfection of water with free chlorine, while primarily developed for potable water, are often used for virus disinfection of nitrified recycled water of &gt;1 NTU (Nephelometric Turbidity Unit). More information is needed on the disinfection efficacy of free chlorine for viruses in waters of varying turbidity and pH due to significant reuse of treated wastewater of varying quality. In this study, disinfection efficacy in nitrified/denitrified activated sludge treated wastewater was investigated for coxsackievirus B5 (CB5), an enterovirus known to be highly resistant to free chlorine. The required chlorine contact times (CT) values (mg.min/L) for inactivation of CB5 were established in treated wastewater at 10 °C and of varying turbidity (0.2, 2, 5 and 20 NTU) and pH (7, 8 and 9). CTs were calculated to achieve 1 to 4 log10 inactivation. Robust data is presented in support of the chlorine CT values required to inactivate a chlorine-resistant virus in a range of turbidities and pHs in treated wastewaters. The testing method used a conservative approach and the data presented have been used to develop the free chlorine virus inactivation guildelines for recycled water in Victoria and South Australia, Australia.

A series of simulations was made with a fallow{wheat crop simulation model to examine the effects of stubble retention and tillage on yield for 2 semi-arid environments in north-western Victoria over a 100-200-year period. The fallow treatments comprised 4 combinations of stubble management and tillage in 18-month-long fallows of a fallow{wheat rotation. The 2 sites are representative of the major soil types of the region: a chromic vertisol at Dooen and a calcic xerosol at Walpeup. Stubble retention had the greatest effect on yield, providing a median increase of 0·8 and 0·6 t/ha at Dooen and Walpeup, respectively. Zero tillage had an importantbut small advantage in the presence of stubble at Dooen (0·2 t/ha) and no significant advantage under any system at Walpeup. Yield response was primarily caused through increased fallow-stored water of approximately 89 and 25 mm at Dooen and Walpeup, respectively. The accumulation of soil mineral nitrogen (SMN) at sowing in fallows did not show the same treatment differences as with water or yield. There was a significant interaction between soil type and fallow method. At Dooen, stubble depressed SMN by about 24 kg N/ha (163{185 kg N/ha) below those without stubble (188-207 kg N/ha). Tillage reduced SMN with or without stubble by about 20 kg N/ha. At Walpeup, on the other hand, the highest SMN was associated with tillage and was enhanced by stubble, but the differences were small (<10 kg N/ha). Nitrogen fertiliser produced a small increase in yield (median 0·2 t/ha) at Dooen, increasing to about 0·4 t/ha in wetter years when stubble was retained and fallows were maintained with zero tillage. Over a 100-year period, nitrogen fertiliser reduced the rate of yield decline. The use of nitrogen fertiliser with stubble retention and zero tillage offers an opportunity for arresting declining yield and quality in intensive cropping systems in the Wimmera region of Victoria.

At South East Water wastewater treatment plants (WwTPs) in Victoria, Australia, biosolids are stockpiled for three years in compliance with the State guidelines to achieve the highest pathogen reduction grade (T1), suitable for unrestricted use in agriculture and landscaping. However, extended stockpiling is costly, may increase odour nuisance and greenhouse gas emissions, and reduces the fertiliser value of the biosolids. A verification programme of sampling and analysis for enteric pathogens was conducted at two WwTPs where sludge is treated by aerobic and anaerobic digestion, air drying (in drying pans or solar drying sheds) and stockpiling, to enumerate and, if present, monitor the decay of a range of enteric pathogens and parasites. The sludge treatment processes at both WwTPs achieved T1 grade biosolids with respect to prescribed pathogenic bacterial numbers (&lt;1 Salmonella spp. 50 g−1 dry solids (DS) and &lt;100 Escherichia coli g−1 DS) and &gt;3 log10 enteric virus reduction after a storage period of one year. No Ascaris eggs were detected in the influent to the WwTPs, confirming previous studies that the presence of helminth infections in Victoria is extremely low and that Ascaris is not applicable as a control criterion for the microbiological quality of biosolids in the region.

A survey of 71 sites was conducted in the dairying districts of south-western Victoria in October 1994 to determine factors associated with nitrogen (N) fixation in white clover based pastures. Twenty-eight factors (environmental, microbiological, management, soil, and pasture) were considered in relation to 2 indicators of N fixation by white clover, %Ndfa (percentage of total plant N derived from the atmosphere, as determined by the 15N natural abundance method) and kg of N fixed per tonne herbage dry matter (legume and non-legume). On light-textured soils (sandy loams), soil potassium, rhizobia numbers, total soil N, and density of the nematode Pratylenchus sp. accounted for 72% of variation in %Ndfa. On medium-textured soils (clay loams), crude protein of perennial ryegrass and plant-available phosphorus in the soil accounted for 30% of variation in %Ndfa. The amount of N fixed was influenced by different factors, again depending on soil texture. Soil chemical properties accounted for 31% variation on the medium-textured soils with nematode density, pasture quality, and soil chemical properties accounting for 77% of variation on light-textured soils. Amounts of N fixed per tonne herbage dry matter produced averaged 8.2 kg on the light-textured soils and 7.3 kg on the medium-textured soils. Average %Ndfa values were 67% and 60% on light- and medium-textured soils, respectively. Effects of soil texture on N fixation were attributed to the different cation exchange and water-holding capacities of the soils and highlight the importance of considering soil type in N fixation studies.

Abstract Several urban centres of different sizes have developed over time, and continue to grow, within the basin of Lake Victoria. Uncontrolled urban development, especially along the lake shore, puts environmental pressure on Lake Victoria and its local ecosystem. This study sought to monitor the extent and impacts of urban development (as measured by population growth and built-up land use/land cover) in the Lake Victoria basin, Kenya, between 1978 and 2018. Remote sensing and GIS-based land use/land cover classification was conducted to extract change in built-up areas from Landsat 3, 4, 5 and 8 satellite imagery obtained for the month of January at intervals of ten years. Change in population distribution and density was analysed based on decadal census data from the Kenya National Bureau of Statistics between 1979 and 2019. A statistical regression model was then estimated to relate population growth to built-up area expansion. Results indicate that the basin’s built-up area has expanded by 97% between 1978 and 2018 while the population increased by 140% between 1979 and 2019. Urban development was attributed to the rapidly increasing population in the area as seen in a positive statistical correlation (R2=0.5744) between increase in built-up area and population growth. The resulting environmental pressure on the local ecosystem has been documented mainly in terms of degradation of lake water quality, eutrophication and aquatic biodiversity loss. The study recommends the enactment and implementation of appropriate eco-sensitive local legislation and policies for sustainable urban and rural land use planning in the area. This should aim to control and regulate urban expansion especially in the immediate shoreline areas of the lake and associated riparian zones.

Responses of fruit trees to reduced irrigation in micro-irrigated peach and apple orchards in the Goulburn Valley, Victoria were investigated during the 2000–01 season. Field experiments examined the effects of applying 2 irrigation levels on soil water content, crop water relations, vegetative growth, yield, yield components and fruit quality. Irrigation regimes were 50% and 100% of current management practice where inputs are scheduled from pan evaporation and locally derived crop coefficients. Water was applied to only one side of the tree rootzone in the 50% treatment (0.5I) while the current management practice treatment (1.0I), received water on both sides of the tree. Over the season, the irrigation inputs for peach and apple equated to a crop coefficient of 0.93 and 0.87, respectively. Orchard water use (ETpeach and ETapple) was predicted using reference crop evapotranspiration (ET0) and published crop coefficients (Kc) with adjustment for the fraction of shade cast by the trees on the orchard floor at solar noon (effective canopy cover, ECC). Throughout the season, ECC measured as midday tree canopy radiation interception, remained low for both peach and apple (<35%). ETpeach and ETapple were substantially lower than current water scheduling practices (1.0I treatments). For the 0.5I apple regime, irrigation closely matched ETapple suggesting that these trees were adequately irrigated. This was supported by no detrimental effects on crop production, vegetative growth, and fruit quality measures of the 0.5I irrigation regime. However, in the peach orchard the 0.5I regime reduced fruit volume suggesting that these trees may have been water stressed. Based on ECC, we calculated the full crop water requirement Kc for the peach and apple orchards to be 0.42 and 0.37, respectively. In summary, for the apple orchard, our 0.5I treatment was close to predicted full crop water requirement (ETapple). But for the peach orchard, the ETpeach was greater, albeit slightly, than our 0.5I regime. Taken overall, these results demonstrate that better matching of water application to the evaporative surface of the orchard canopies (i.e. ECC) can substantially reduce irrigation water use in Goulburn Valley orchards. It is also apparent that ECC in these orchards where row spacing is typically 4–5 m can be relatively low.

With ever-increasing demands being made on remote and natural lands, planners and managers require more detailed information than hitherto to assist them in monitoring the status of this wilderness resource and developing appropriate and effective management prescriptions. These requirements are addressed by a computer-based wilderness evaluation procedure that has been developed for a national wilderness survey of Australia.The methodology, based on the wilderness continuum concept (Lesslie & Taylor, 1985), places emphasis on measuring variation in wilderness quality by using four indicators that represent the two essential attributes of remoteness and naturalness. This permits a precise assessment to be made of the wilderness resource, revealing those factors which contribute to or compromise wilderness quality. The computer-based storage and analysis of data enables surveys to be conducted over large, even continental, areas, yet at a relatively fine level of resolution that is appropriate to localized planning needs.Trial application to the State of Victoria, Australia, demonstrates that the survey procedure can be successfully adapted to a wide range of environments, use-patterns, data-base characteristics, and management objectives, which should be applicable and very widely useful elsewhere.

The effects of combinations of different fertiliser rates and grazing methods applied to phalaris-based pastures on an acid, saline, yellow sodosol on the Dundas Tablelands of western Victoria (mean annual rainfall 623�mm) were measured from 1997 to 2000. The objective was to help identify management systems that improve phalaris growth and persistence, water use, and animal production, and thereby the productivity and sustainability of grazing systems. Pastures were either set stocked with low [mean 6.4 kg phosphorus (P)/ha.year] or high (mean 25 kg P/ha.year) fertiliser rates, or rotationally grazed with high fertiliser (mean 25 kg P/ha.year). Rotational grazing was implemented as either a simple '4-paddock' system (fixed rotation length), or a more intensive system where rotation length varied with pasture growth rate. Unreplicated paddocks of volunteer pasture (dominated by onion grass and annual grass weeds) receiving an average of 8 kg P/ha.year were also monitored. All treatments were stocked with spring-lambing Merino ewes. Stocking rate was an emergent property of each treatment, and was driven by pasture quality and availability. Total pasture herbage accumulation ranged from 7150 to 9750 kg DM/ha.year and was significantly lower on the set-stocked, low-fertility treatment than on all other treatments. A significant treatment.day effect in the spline analysis of herbage mass was explained by a trend toward higher pasture mass in the rotationally grazed treatments than set-stocked treatments from the break of season until mid-spring. Rotational grazing led to significantly higher phalaris herbage accumulation than set stocking (mean 3680 v. 2120 kg DM/ha.year), but significantly lower subterranean clover herbage accumulation (1440 v. 2490 kg DM/ha.year). Despite the stronger growth of deep-rooted phalaris in the rotationally grazed treatments, maximum soil water deficits at the end of summer differed only slightly between treatments, with the difference between driest and wettest treatments amounting to only 14 mm. Summer growth of phalaris was apparently insufficient to generate significant differences in soil water extraction at depth, even when phalaris content was increased by rotational grazing, and re-wetting of the soil profile occurred at a similar rate for all treatments. Rotationally grazed treatments supported higher stocking rates than set-stocked treatments at high fertiliser rates (mean 14.9 v. 13.7 ewes/ha), but apparent losses in pasture feeding value due to lower legume content under rotational grazing meant that there were few significant differences between treatments in lamb production per hectare. The experiment showed that grazing method can have a substantial and rapid effect on pasture botanical composition. There are clear opportunities for producers to use temporal and spatial combinations of set stocking and rotational grazing to manipulate herbage mass and pasture composition within broad target ranges for achieving both animal production (e.g. high per-head animal performance) and sustainability (e.g. persistence of perennial grasses) objectives. Rigid application of either set stocking or rotational grazing imposes limitations on both pasture and animal production, and neither grazing method will optimise system performance under all conditions. The experiment also demonstrated that management and land-use changes that have much greater potential to increase water use than those examined here will be needed to ensure the sustainability of pasture systems in the high rainfall zone of western Victoria.

The Esso Long Island Point facility is situated on the edge of Western Port, an important Ramsar designated wetland for migratory birds in Victoria, Australia. The gas fractionation and crude oil storage facility has operated for over 40 years and has discharged treated wastewater to Western Port for most of these years in accordance with its environmental regulatory licence. The 2003 State Environment Protection Policy for Waters of Western Port is the Victorian Environment Protection Authority’s regulatory framework for licensing wastewater discharges to the wetland, and among other items, requires that discharges must cause no ‘detrimental change in the environmental quality of the receiving waters’ or ‘chronic impacts outside any declared mixing zone’. A major upgrade to the water treatment facility in 2010 included a risk-based marine ecosystem program to monitor key environmental indicators including water quality, jetty pile invertebrate communities and seagrass condition. The program’s longer-term monitoring record has allowed assessment of potential chronic effects on invertebrates and seagrass by comparing temporal changes at monitoring sites over the period from pre-operations (2010) to present (2016) and spatial changes between near-field to far-field sites, kilometres from the discharge point. The program has shown that management of the discharge maintains beneficial uses and environmental objectives at the boundary of the mixing zone, and the marine ecosystem is protected from potentially slower and longer-term adverse effects in the far-field. The program demonstrates that the treated wastewater discharge has had no adverse impact on key environmental indicators in Western Port over the longer-term study period.

Some of the highest nitrous oxide (N2O) emissions arising from Australian agriculture have been recorded in the high-rainfall zone (>650mm) of south-western Victoria. Understanding the association between nitrogen (N) management, crop N uptake and gaseous losses is needed to reduce N2O losses. Field experiments studied the effect of N-fertiliser management on N2O emissions, crop N uptake and crop productivity at Hamilton and Tarrington in south-western Victoria. Management included five rates of urea-N fertiliser (0, 25, 50, 100 and 200kgN/ha) topdressed at either mid-tillering or first-node growth stages of wheat development; urea-N deep-banded 10cm below the seed at sowing; and urea coated with the nitrification inhibitor DMPP (3,4-dimethylpyrazole phosphate) was either topdressed or deep-banded. Pre-sowing soil profile chemical properties were determined before static chambers were installed to measure N2O losses, accompanied by wheat dry matter, crop N uptake and grain yield and quality, to measure treatment differences. N2O losses increased significantly (P≤0.10) where urea-N was deep-banded, resulting in a 2–2.5-fold increase in losses, compared with the nil N control. The high N2O losses from deep-banding N appeared to result from winter waterlogging triggering gaseous or drainage losses before wheat reached peak growth and demand for N in spring. Despite the high losses from deep-banding urea-N, grain yields were largely unaffected by N management, except at Hamilton in 2012, where topdressed wheat growing in a soil with large reserves of NO3–-N, and later experiencing post-anthesis water deficit resulted in a negative grain yield response. All sites had high concentrations of soil organic carbon (>2.8%) and the potential for large amounts of N mineralisation throughout the growing season to supplement low N fertiliser recovery. However, topdressed urea-N resulted in significant enrichment of crop tissue (P≤0.004) and associated positive response in grain protein compared with the deep banded and nil N treatments. 3,4-Dimethylpyrazole phosphate (DMPP)-coated urea provided no additional benefit to crop yield over conventional urea N. Our study highlighted the importance of synchronising N supply with peak crop N demand to encourage greater synthetic N uptake and mitigation of N2O losses.

Phosphorus (P) and nitrogen (N) exports from cropping areas can be greater than those from uncropped areas. Conservation farming methods, involving minimal tillage and full stubble retention, offer significant benefits to grain cropping, but may increase nutrient concentrations in surface (i.e. 0–20 mm) soils, resulting in increased risks of nutrient mobilisation and loss. The effects of tillage and stubble management on soil nutrients that are potentially mobilised into runoff from a long-term trial site at Rutherglen (established in 1981) were investigated. On 2 different sampling dates (February and August 2006) soils from the 0–20, 20–50, and 50–150 mm depths were collected from 3 treatments: conventional cultivation with stubble burning (CCb); direct drill with stubble burning (DDb); and direct drill with stubble retained (DDr). In 2004, the trial was sown with wheat (Triticum aestivum cv. Dollarbird), followed by faba beans in 2005 (Vicia faba L.) and wheat again in 2006. In August 2006, a rainfall simulation experiment was also conducted on these sites. All nutrient concentrations decreased with depth to 150 mm in all treatments, when both sampling dates were analysed together. This indicated that soil nutrient stratification was occurring in all 3 treatments. The CCb treatment only displayed differences between the 0–20 and 20–50 mm depths for soil organic C and ammonium-N. DDr significantly increased some nutrient concentrations in the 0–20 mm soil depth compared with the CCb treatment, including CaCl2-extractable P (0.76 and 0.50 mg/kg, for DDr and CCb, respectively), total N (1.23 and 1.00 g/kg, for DDr and CCb, respectively), and nitrate-N (12.6 and 8.63 mg/kg, for DDr and CCb, respectively), while the ammonium-N concentration was greater under CCb (9.71 mg/kg) than DDr (6.46 mg/kg). Being water-soluble, CaCl2-extractable P and nitrate-N are more likely be mobilised into streams from the 0–20 mm depth, where they are highly bioavailable and may contribute to increased eutrophication. Direct drilling with stubble retention contributed a greater proportion of particulate P and N to TP (Total P) and TN (Total N) in surface runoff than either of the burnt systems. Particulate P accounted for 75%, 67%, and 83% of TP in surface runoff from the CCb, DDb, and DDr treatments, respectively. However, the highly bioavailable dissolved reactive P (DRP) was the dominant form of dissolved P, with concentrations exceeding the recommended guidelines of 0.05 mg P/L in the lowlands of south-east Australia. Total N (0.44, 0.68, and 0.73 mg N/L for DDr, DDb, and CCb, respectively) in surface runoff was dominated by nitrate-N and also exceeded current Australian guidelines of 0.5 mg N/L, except for TN from the DDr treatment. These results would indicate that P, particularly the non-dominant but highly bioavailable form of DRP, exported from these systems is more likely to adversely affect catchment water quality than N exports. The increase in surface runoff volumes and nutrient loads from the CCb treatment observed in this study indicate that DDr systems have increased soil infiltration properties and retained nutrients within the soil–plant system. Therefore, direct drilling with stubble retention in the high rainfall zone cropping areas of north-east Victoria is more likely to retain nutrients on-site and improve soil fertility than burning stubble and cultivating the soil.

The impacts of excessive nitrogen loading to streams in a watershed occur in the receiving waters such as rivers at the outlet of the watershed. To quantify the impacts of land use and management practices on the nitrogen loading at the watershed outlet, simulation models are needed that can both predict the nitrogen loading at the edge of individual fields and predict the fate of nitrogen as it moves through the river network to the watershed outlet. This paper presents the results of a model analysis for describing the processes governing transformations and transport of nitrogen compounds (NO3-N and NH4-N) through Mtakuja River in the Geita wetland. The model was made in Soil and Water Assessment Tool (SWAT), a watershed model developed to assess the impact of land management practices on water, sediment and agricultural chemical yields with varying soils, land use and management conditions. Two monitoring stations namely MTSP1 and MTSP2 were established along Mtakuja River. A set of SWAT model inputs representative of the water conditions was collected from the established monitoring stations. The model was calibrated and validated for the prediction of flow and nitrogen compounds (NO3-N and NH4-N) transport, against a set of measured mean monthly monitoring data. Sensitive model parameters were adjusted within their feasible ranges during calibration to minimize model prediction errors. At the gauging station MTSP2, the calibration results showed that the model predicted mean monthly flow within 18% of the measured mean monthly flow with the r2 coefficient and Nash-Sutcliffe (NSE) were 0.84 and 0.82, respectively. At the water quality monitoring station MTSP2, the calibration results showed the model predicted nitrogen compounds (NO3-N and NH4-N) loadings within 21% and 23% of their respective measured mean monthly loadings. The mean monthly comparisons of r 2 values for nitrogen compounds ranged from 0.77 to 0.81 while the Nash-Sutcliffe Efficiency (NSE) values were between 0.72 and 0.73. The model results and field measurements demonstrated that about 70% of the annual nitrogen compounds loadings which would otherwise reach Lake Victoria are retained in the wetland. The Mtakuja river model can therefore be used for prediction of nitrogen compounds (NO3-N and NH4-N) transformation processes in the Geita wetland.

A major barrier to the adoption of precision agriculture in dryland cropping systems is our current inability to reliably predict spatial patterns of grain yield for future crops for a specific paddock. An experiment was undertaken to develop a better understanding of how edaphic and climatic factors interact to influence the spatial variation in the growth, water use, and grain yield of different crops in a single paddock so as to improve predictions of the likely spatial pattern of grain yields in future crops. Changes in a range of crop and soil properties were monitored over 3 consecutive seasons (barley in 2005 and 2007 and lentils in 2006) in the southern section of a 167-ha paddock in the Mallee region of Victoria, which had been classified into 3 different yield (low, moderate, and high) and seasonal variability (stable and variable) zones using normalised difference vegetation index (NDVI) and historic yield maps. The different management zones reflected marked differences in a range of soil properties including both texture in the topsoil and potential chemical-physical constraints in the subsoil (SSCs) to root growth and water use. Dry matter production, grain yield, and quality differed significantly between the yield zones but the relative difference between zones was reduced when supplementary irrigation was applied to barley in 2005, suggesting that some other factor, e.g. nitrogen (N), may have become limiting in that year. There was a strong relationship between crop growth and the use of soil water and nitrate across the management zones, with most water use by the crop occurring in the pre-anthesis/flowering period, but the nature of this relationship appeared to vary with year and/or crop type. In 2006, lentil yield was strongly related to crop establishment, which varied with soil texture and differences in plant-available water. In 2007 the presence of soil water following a good break to the season permitted root growth into the subsoil where there was evidence that SSCs may have adversely affected crop growth. Because of potential residual effects of one crop on another, e.g. through differential N supply and use, we conclude that the utility of the NDVI methodology for developing zone management maps could be improved by using historical records and data for a range of crop types rather than pooling data from a range of seasons.

Urban greenery is an essential characteristic of the urban ecosystem, which offers various advantages, such as improved air quality, human health facilities, storm-water run-off control, carbon reduction, and an increase in property values. Therefore, identification and continuous monitoring of the vegetation (trees) is of vital importance for our urban lifestyle. This paper proposes a deep learning-based network, Siamese convolutional neural network (SCNN), combined with a modified brute-force-based line-of-bearing (LOB) algorithm that evaluates the health of Eucalyptus trees as healthy or unhealthy and identifies their geolocation in real time from Google Street View (GSV) and ground truth images. Our dataset represents Eucalyptus trees’ various details from multiple viewpoints, scales and different shapes to texture. The experiments were carried out in the Wyndham city council area in the state of Victoria, Australia. Our approach obtained an average accuracy of 93.2% in identifying healthy and unhealthy trees after training on around 4500 images and testing on 500 images. This study helps in identifying the Eucalyptus tree with health issues or dead trees in an automated way that can facilitate urban green management and assist the local council to make decisions about plantation and improvements in looking after trees. Overall, this study shows that even in a complex background, most healthy and unhealthy Eucalyptus trees can be detected by our deep learning algorithm in real time.

There is increasing environmental pressure to dispose of waste effluents on land, rather than discharging them directly into surface waterways. In addition to reducing impacts on water quality, land disposal of effluents offers the possibility of beneficial recycling of water and essential plant nutrients. Frequently, however, waste water contains high concentrations of dissolved salts, particularly sodium, that can affect the levels of salinity and sodicity in soils. This, in turn, can diminish the utility of soils for productive agriculture. Astute soil management can often ameliorate these adverse affects but this may require land-use practices that reduce the commercial return from farming activities. It is therefore important to identify the main purpose of effluent disposal areas and to compensate land users appropriately when the operation of the effluent disposal scheme affects farm profitability. If farmers are forced by commercial pressures to adopt inappropriate land use practices on areas used for effluent disposal, the operation of the scheme will be compromised, and there may even be the risk of complete failure. The results of a limited number of experiments investigating the application of effluents to land in northern Victoria are used to demonstrate these risks. The effects on soil chemical properties of applying saline–sodic waste water to land are now well understood. Considerably less certain are the effects of these changes on soil chemical properties, on the physical properties of soils and the way soils behave under various land uses — such as cultivation or grazing by heavy animals. Various approaches to modelling and predicting the impacts on soil of irrigation with saline–sodic waste water are discussed. A number of simple, classification models, based on practical experience and empirical equations, currently provide valuable assistance for land managers. More complex, mechanistic models have been developed that describe successfully the movement of water and salts through soils, given appropriate soil measurements as input parameters. The major limitations now are the availability of soil data at an appropriate scale and an understanding of the ways changes in soil chemical properties affect soil physical properties and subsequent soil behaviour. In particular there is a need to investigate those critical zones at the soil surface or the top of the B horizon where water movement is impeded in sodic soils.

Abstract. The Hydrologic Reference Stations is a network of 467 high-quality streamflow gauging stations across Australia that is developed and maintained by the Bureau of Meteorology as part of an ongoing responsibility under the Water Act 2007. The main objectives of the service are to observe and detect climate-driven changes in observed streamflow and to provide a quality-controlled dataset for research. We investigate trends and step changes in streamflow across Australia in data from all 467 streamflow gauging stations. Data from 30 to 69 years in duration ending in February 2019 were examined. We analysed data in terms of water-year totals and for the four seasons. The commencement of the water year varies across the country – mainly from February–March in the south to September–October in the north. We summarized our findings for each of the 12 drainage divisions defined by Australian Hydrological Geospatial Fabric (Geofabric) and for continental Australia as a whole. We used statistical tests to detect and analyse linear and step changes in seasonal and annual streamflow. Monotonic trends were detected using modified Mann–Kendall (MK) tests, including a variance correction approach (MK3), a block bootstrap approach (MK3bs) and a long-term persistence approach (MK4). A nonparametric Pettitt test was used for step-change detection and identification. The regional significance of these changes at the drainage division scale was analysed and synthesized using a Walker test. The Murray–Darling Basin, home to Australia's largest river system, showed statistically significant decreasing trends for the region with respect to the annual total and all four seasons. Drainage divisions in New South Wales, Victoria and Tasmania showed significant annual and seasonal decreasing trends. Similar results were found in south-western Western Australia, South Australia and north-eastern Queensland. There was no significant spatial pattern observed in central nor mid-west Western Australia, with one possible explanation for this being the sparse density of streamflow stations and/or the length of the datasets available. Only the Tanami–Timor Sea Coast drainage division in northern Australia showed increasing trends and step changes in annual and seasonal streamflow that were regionally significant. Most of the step changes occurred during 1970–1999. In the south-eastern part of Australia, the majority of the step changes occurred in the 1990s, before the onset of the “Millennium Drought”. Long-term monotonic trends in observed streamflow and its regional significance are consistent with observed changes in climate experienced across Australia. The findings of this study will assist water managers with long-term infrastructure planning and management of water resources under climate variability and change across Australia.

Acidification of non arable soils under long-term pasture presents a major agricultural problem in the high rainfall areas (≥600 mm/year) of central and southern New South Wales and north-eastern Victoria. Some of these soils were already strongly acid to depth before agriculture. Evidence suggests that persistence of pasture species tolerant of acidic soils is being affected adversely on a number of severely acidic soils. Acidification processes are well understood but the capacity for grazing enterprises to pay for amendment by lime application is a major constraint in long-term pasture areas. In addition, soil acidification is likely to have substantial off-site effects on water quantity and quality and as a result, on dryland salinity. However, there is a paucity of scientific evidence to link soil acidity and dryland salinity in this way. Production from a grazing enterprise can be maintained by selecting plants for tolerance of acidity, surface application of lime or a combination of both. Responses by subterranean clover, lucerne and perennial grass (mainly phalaris and cocksfoot)-based pastures to incorporated lime are reported, but there is limited evidence of responses to surface applied lime. The movement of the lime effect into the soil from surface application is suggested as a major factor in controlling lime responses by plants. There is a need for more confidence in the benefits of topdressed lime in non arable soils before producers are likely to adopt the practice. High subsurface acidity in many soils is a major limitation to the range of species that can be grown. In the longer term, the use of lime may remove constraints on the use of productive species such as lucerne. Other options for acidic soils where slope is less than 10% are for the grazing system to be modified or intensified, or for crop or horticultural production. Costs of lime could be justified through more profitable enterprises than traditional grazing operations. Low input systems based on native grasses are intrinsically appealing, however, this is only possible where a premium is paid for such produce (such as super fine wool). Forestry is an option where suitable land and infrastructure are present and should slow soil acidification and minimise off-site impacts. Land retirement may be a useful option for some parts of the landscape that contribute disproportionately to environmental problems. Private and government funded land retirement may have a role to play.

Winter wheat cultivars are defined as those that have an obligate vernalisation requirement that must be met before they will progress from the vegetative to reproductive phase of development i.e. they must experience a true winter before they will flower. Historically, very little breeding effort has been applied to the selection of winter cultivars suited to southern Australia, with the notable exception of the New South Wales Agriculture breeding program based in Wagga and Temora that ran from the 1960s until 2002. A shift by growers to earlier sowing, increased usage of dual-purpose cereals, and research highlighting the whole-farm benefits of winter cultivars to average farm wheat yield has increased grower interest and demand for winter cultivars. Three major wheat breeding companies operating in southern Australia have responded by commencing selection for milling quality winter cultivars, the first of which was released in 2017. Existing research relating to winter wheats in southern Australian farming systems is reviewed here, including interactions with agronomic management, environment and weeds and disease. It is concluded that winter wheats can offer significant production and farming system benefits to growers by allowing earlier establishment, which increases water-limited potential yield (PYw) by ~15% relative to later sown spring wheats, and makes forage available for dual-purpose grazing during vegetative development. Winter wheats sown early require agronomic management different to that of later sown spring wheats, including greater attention to control of grass weeds and certain diseases. There are significant research gaps that will prevent growers from maximising the opportunities from new winter cultivars once they are released. The first of these is a well-defined establishment window for winter cultivars, particularly in medium-low rainfall environments of South Australia, Victoria and Western Australia that have not historically grown them. There is circumstantial evidence that the yield advantage of early established winter wheats over later sown spring wheats is greatest when stored soil water is present at establishment, or the soil profile fills during the growing season. Explicit confirmation of this would allow growers to identify situations where the yield advantage of winter wheats will be maximised. Given the imminent release of several new winter wheat cultivars and the increases in PYw that they embody, it is critical to experimentally define the management and environmental conditions under which performance of these new genotypes are optimised, before their release and availability to growers. Optimising the genotype × environmental × management interactions possible with these cultivars will empower growers to make the best use of the technology and better realise the gains in water limited potential yield possible with these genotypes.

To assess the risks and benefits of more intensive pasture management, 2 or 3 treatments with contrasting fertiliser regimes were selected from each site of the Sustainable Grazing Systems national experiment. The assessment used soil coring data, modelling and runoff nutrient concentration data.Soil acidification rates were estimated from the simulated nitrate leaching and product removal estimated from the stocking rates at each site. Much higher acidification rates were estimated at sites in Victoria and southern Western Australia than in northern New South Wales. This was because of a lower level of nitrate leaching in summer-dominant rainfall environments coupled with lower stocking rates. Simulations showed highest nitrate leaching on annual pastures, but that a phalaris pasture could reduce this, and a kikuyu pasture could almost fully control leaching.The concentration of P in surface runoff was related to soil P status at the 4 southern sites, indicating that greater use of P fertiliser would increase P movement into waterways. There was no relationship between soil P status and P in surface runoff at the northern New South Wales sites, and across all sites there were no relationships between P fertility and runoff N levels. Concentrations of P and N in runoff greatly exceeded stream water quality guidelines, even on treatments where only minimal P had been applied as fertiliser. There was also evidence of high spatial variation in surface runoff generation, with surface runoff from some plots less than 5% of the streamflow in nearby reference streams. There is therefore scope to control P concentrations in streams by retiring from production the parts of the landscape that generate high quantities of surface flow, but to intensify production on areas that produce little runoff.

Carrum Carrum Swamp was a vast wetland to the south-east of Melbourne, Victoria, Australia, at the time that it was first sighted by white colonists in 1803. By 1878, the colonists had commenced converting the swamp to dry land for agricultural and horticultural pursuits, and 100 years later it was predominantly residential land. Shifting values in the 1970s led to environmental concerns about water quality in local creeks and Port Phillip Bay and subsequent residential development on the former swamp included the construction of stormwater treatment wetlands. Perceptions of wetlands are now diverse, including positive perceptions that support their presence in urban settings. In contrast, traditionally, wetlands have been perceived negatively, as waste lands, leading to their drainage. Nevertheless, alternative, perhaps positive, perceptions could have existed, only to be overwhelmed by the negative perceptions driving drainage. Understanding the full range of past perceptions is important to ensure that the historical record is correct and to provide historical context to contemporary perceptions of wetlands. It will better equip natural resource managers and designers and managers of constructed wetlands in urban locations to ensure that wetlands are healthy, functioning and appreciated by their local and wider communities. Thus, the perceptions of Carrum Carrum Swamp by colonists from 1803 to 1878 were examined through qualitative content analysis of historical documents, and a typology was developed. Seven different perceptions were identified: scientific, premodern, exploitative, romantic, aesthetic, medico-mythic and ecological. Most could be traced to the colonists’ predominantly British heritage, but one perception arose in the colony in response to the specific environmental conditions that the colonists encountered. This ecological perception valued wetlands as places of predictable water supply in a land of unpredictable rainfall. It recognised wetlands as part of a broader hydrological system, with influences on the local climate. Its proponents promoted the need for a different approach to the management of wetlands than in Britain and Europe. Nevertheless, a dominant exploitative perception prevailed, leading to the drainage of Carrum Carrum Swamp. The typology developed in this study will be useful for exploring perceptions of other wetlands, both colonial and contemporary.

Abstract. The Soil and Water Assessment Tool (SWAT) is an integrated river basin model that is widely applied within the Nile basin. Up to date, more than 20 peer-reviewed papers describe the use of SWAT for a variety of problems in the upper Nile basin countries, such as erosion modelling, land use and climate change impact modelling and water resources management. The majority of the studies are focused on locations in the tropical highlands in Ethiopia and around Lake Victoria. The popularity of SWAT is attributed to the fact that the tool is freely available and that it is readily applicable through the development of geographic information system (GIS) based interfaces and its easy linkage to sensitivity, calibration and uncertainty analysis tools. The online and free availability of basic GIS data that are required for SWAT made its applicability more straightforward even in data-scarce areas. However, the easy use of SWAT may not always lead to appropriate models which is also a consequence of the quality of the available free databases in these regions. In this paper, we aim at critically reviewing the use of SWAT in the context of the modelling purpose and problem descriptions in the tropical highlands of the Nile basin countries. To evaluate the models that are described in journal papers, a number of criteria are used to evaluate the model set-up, model performances, physical representation of the model parameters, and the correctness of the hydrological model balance. On the basis of performance indicators, the majority of the SWAT models were classified as giving satisfactory to very good results. Nevertheless, the hydrological mass balances as reported in several papers contained losses that might not be justified. Several papers also reported the use of unrealistic parameter values. More worrying is that many papers lack this information. For this reason, most of the reported SWAT models have to be evaluated critically. An important gap is the lack of attention that is given to the vegetation and crop processes. None of the papers reported any adaptation to the crop parameters, or any crop-related output such as leaf area index, biomass or crop yields. A proper simulation of the land cover is important for obtaining correct runoff generation, evapotranspiration and erosion computations. It is also found that a comparison of SWAT applications on the same or similar case study but by different research teams and/or model versions resulted in very different results. It is therefore recommended to find better methods to evaluate the representativeness of the distributed processes and parameters (especially when land use studies are envisaged) or predictions of the future through environmental changes. The main recommendation is that more details on the model set-up, the parameters and outputs should be provided in the journal papers or supplementary materials in order to allow for a more stringent evaluation of these models.

China Shale-Gas Field Sets Production Record Sinopec recorded China’s highest daily output of shale gas at 20.62 million cubic meters (Mcm) at its Fuling shale-gas field in Chongqing, China, a key gas source for the Sichuan-East gas pipeline. The first major commercial shale-gas project in China, Fuling has continuously broken records for the shortest gasfield drilling cycle while significantly increasing the drilling of high-quality reservoirs covering more than 3 million m, according to Sinopec. Gasfield production construction was also expanded to raise production capacity. The company said the field maintains a daily output of 20 Mcm, producing an estimated 6.7 Bcm per year. Apache and Total Plan Suriname Appraisals Apache filed appraisal plans for its Maka and Sapakara oil discoveries in block 58 offshore Suriname. The company said another submission is expected for Kwaskwasi, the largest find in the block, by the end of the year. Operations continue for Keskesi, the fourth exploration target. There are plans to drill a fifth prospect at Bonboni in the North-Central portion of the concession. Partner company Total is assuming operatorship of the block ahead of next year’s campaigns. BP Emerges as Sole Bid for Offshore Canada Parcels BP was the only operator to place a bid in the Canada-Newfoundland and Labrador Offshore Petroleum Board (C-NLOPB) Call for Bids NL20-CFB01, which offered 17 parcels (4,170,509 hectares) in the eastern Newfoundland region. The successful bid was for Parcel 9 (covering 264,500 hectares) for $27 million in work commitments from BP Canada Energy Group. Subject to BP satisfying specified requirements and receiving government approval, the exploration license will be issued in January 2021. No bids were received for the remaining 16 parcels, which may be reposted in a future Call for Bids. Criteria for selecting a winning bid is the total amount the bidder commits to spend on exploration of the parcel during the first period of a 9-year license, with a minimum acceptable bid of $10 million in work commitments for each parcel. Beach Energy To Drill Otway Basin Well Beach Energy plans to drill at its Artisan-1 well about 32 km offshore Victoria, Australia, in the Otway basin, before the end of 2021. The well, located on Block Vic/P43, was to be spudded in 1H 2020 but was delayed due to COVID-19. The timeframe for drilling was confirmed by the National Offshore Petroleum Safety and Environmental Management Authority, which also said Beach is keeping open the option to suspend the well and develop it, pending reservoir analysis. Anchors, mooring chains, and surface buoys have already been laid for the well, which is in a water depth of approximately 71 m. The well is expected to take approximately 35–55 days to drill, depending on the final work program and potential operational delays. Diamond Offshore’s semisubmersible Ocean Onyx was contracted for the drilling program. Artisan is the first of Beach’s planned multiwell campaigns, which also include development wells at the Geographe and Thylacine fields. Hess Completes Sale of Interest in Gulf of Mexico Field Hess completed the sale of its 28% working interest in the Shenzi Field in the deepwater Gulf of Mexico (GOM) to BHP, the field’s operator, for $505 million. Shenzi is a six-lease development structured as a joint ownership: BHP (operator, 44%), Hess (28%), and Repsol (28%). The acquisition would bring BHP’s working interest to 72%, adding approximately 11,000 BOE/D of production (90% oil). The sale is expected to close by December 2020. Hess CEO John Hess said proceeds from the sale will help fund the company’s investment in Guyana. Greenland Opens New Offshore Areas Greenland opened three new offshore areas for application of oil and gas exploitation licenses off West Greenland. The areas are Baffin Bay, Disko West, and Davis Strait. The country also said it is working on an oil strategy to reduce geological uncertainty by offering an investment package to companies that engage in its Open Door Procedures. The procedures are a first-mover advantage to remove national oil company Nunaoil, as a carried partner, reducing turnover and surplus royalties. It is estimated to reduce the government take by 51.3% to 40.6%. Shell and Impact Oil & Gas Agree to South Africa Farmout Africa Oil announced Impact Oil & Gas entered into two agreements for exploration areas offshore South Africa. The company has a 31.10% share-holding in Impact, a privately owned exploration company. Impact entered into an agreement with BG International, a Shell subsidiary, for the farm-out of a 50% working interest and operatorship in the Transkei and Algoa exploration rights. Shell was also granted the option to acquire an additional 5% working interest should the joint venture (JV) elect to move into the third renewal period, expected in 2024. Algoa is located in the South Outeniqua Basin, east of Block 11B/12B, containing the Brulpadda gas condensate discovery and where Total recently discovered gas condensate. The Transkei block is northeast of Algoa in the Natal Trough Basin where Impact has identified highly material prospectivity associated with several large submarine fan bodies, which the JV will explore with 3D seismic data and then potential exploratory drilling. Impact and Shell plan to acquire over 6,000 km² of 3D seismic data during the first available seismic window following completion of the transaction. This window is expected to be in the Q1 2022. After the closing of the deal, Shell will hold a 50% interest as the operator and Impact will hold 50%. Impact also entered into an agreement with Silver Wave Energy for the farm-in of a 90% working interest and operatorship of Area 2, offshore South Africa. East and adjacent to Impact’s Transkei and Algoa blocks, Area 2 complements Impact’s existing position by extending the entire length of the ultradeepwater part of the Transkei margin. Together, the Transkei and Algoa Blocks and Area 2 cover over 124,000 km2. Area 2 has been opened by the Brulpadda and Luiperd discoveries in the Outeniqua Basin and will be further tested during 2021 by the well on the giant Venus prospect in ultradeepwater Namibia, where Impact is a partner. Impact believes there is good evidence for this Southern African Aptian play to have a common world-class Lower Cretaceous source rock, similar excellent-quality Apto-Albian reservoir sands, and a geological setting suitable for the formation of large stratigraphic traps. Following completion of the farm-in, Impact will hold 90% interest and serve as the operator; Silver Wave will hold 10%. Petronas Awards Sarawak Contract to Seismic Consortium The seismic consortium comprising PGS, TGS, and WesternGeco was awarded a multiyear contract by Petronas to acquire and process up to 105,000 km2 of multisensor, multiclient 3D data in the Sarawak Basin, offshore Malaysia. The contract award follows an ongoing campaign by the consortium in the Sabah offshore region, awarded in 2016, in which over 50,000 km2 of high-quality 3D seismic data have been acquired and licensed to the oil and gas industry to support Malaysia license round and exploration activity. The Sarawak award will allow for a multiphase program to promote exploration efforts in the prolific Sarawak East Natuna Basin (Deepwater North Luconia and West Luconia Province). The consortium is planning the initial phases and is engaging with the oil and gas industry to secure prefunding ahead of planned acquisition, covering both open blocks and areas of existing farm-in opportunities. Total Discovers Second Gas Condensate in South Africa Total made a significant second gas condensate discovery on the Luiperd prospect, located on Block 11B/12B in the Outeniqua Basin, 175 km off the southern coast of South Africa. The discovery follows the adjacent play-opening Brulpadda discovery in 2019. The Luiperd-1X well was drilled to a total depth of about 3,400 m and encountered 73 m of net gas condensate pay in well-developed, good-quality Lower Cretaceous reservoirs. Following a coring and logging program, the well will be tested to assess the dynamic reservoir characteristics and deliverability. The Block 11B/12B covers an area of 19,000 km2, with water depths ranging from 200 to 1800 m. It is operated by Total with a 45% working interest, alongside Qatar Petroleum (25%), CNR International (20%), and Main Street, a South African consortium (10%). The Luiperd prospect is the second to be drilled in a series of five large submarine fan prospects with direct hydrocarbon indicators defined utilizing 2D and 3D seismic data. BP Gas Field Offshore Egypt Begins Production BP started gas production from its Qattameya gasfield development ‎offshore Egypt in the North Damietta offshore concession. Through BP’s joint venture Pharaonic Petroleum Company working with state-owned Egyptian Natural Gas Holding Co., the field, which is ‎expected to produce up to 50 MMcf/D, was developed through a one-well subsea development and tieback to existing infrastructure.‎ Qattameya, whose discovery was announced in 2017, is located approximately 45 km west ‎of the Ha’py platform, in 108 m of water. It is tied back to the Ha’py and Tuart field ‎development via a new 50-km pipeline and connected to existing subsea ‎utilities via a 50-km umbilical. ‎BP holds 100% equity in the North Damietta offshore concession in the East Nile Delta. ‎Gas production from the field is directed to Egypt’s national grid.

The impact of agricultural intensification on soil degradation now is occurring in tropical countries. The objective of this study was to determine the effect of long-term tillage and N fertilization on soil properties and crop yields in corn-soybean rotation. This long-term study which initiated since 1987 was carried out on a Typic Fragiudult soil at Politeknik Negeri Lampung, Sumatra (105o13’45.5"-105o13’48.0"E, 05o21’19.6"-05o21’19.7"S) in 2010 and 2011. A factorial experiment was arranged in a randomized block design with four replications. The first factor was tillage system namely intensive tillage (IT) and conservation tillage (CT) which consist of minimum tillage (MT) and no-tillage (NT); while the second factor was N fertilization with rates of 0, 100 and 200 kg N ha-1 applied for corn, and 0, 25, and 50 kg N ha-1 for soybean. The results showed that bulk density and soil strength at upper layer after 24 years of cropping were similar among treatments, but the soil strength under IT at 50-60 cm depth was 28.2% higher (p<0.05) than NT. Soil moisture and temperature under CT at 0-5 cm depth were respectively 38.1% and 4.5% higher (p<0.05) than IT. High N rate decreased soil pH at 0-20 cm depth as much as 10%, but increased total soil N at 0-5 cm depth as much as 19% (p<0.05). At 0-10 cm depth, MT with no N had highest exchangeable K, while IT with medium N rate had the lowest (p<0.05). At 0-5 cm depth, MT with no N had highest exchangeable Ca, but it had the lowest (p<0.05) if combined with higher N rate. Microbial biomass C throughout the growing season for NT was consistently highest and it was 14.4% higher (p<0.05) than IT. Compared to IT, Ap horizon of CT after 24 years of cropping was deeper, with larger soil structure and more abundance macro pores. Soybean and corn yields for long-term CT were 64.3% and 31.8% higher (p<0.05) than IT, respectively. Corn yield for long-term N with rate of 100 kg N ha-1 was 36.4% higher (p<0.05) than with no N.Keywords: Conservation tillage, crop yields, N fertilization, soil properties[How to Cite: Utomo M, IS Banuwa, H Buchari, Y Anggraini and Berthiria. 2013.Long-term Tillage and Nitrogen Fertilization Effects on Soil Properties and Crop Yields. J Trop Soils 18 (2): 131-139. Doi: 10.5400/jts.2013.18.2.131][Permalink/DOI: www.dx.doi.org/10.5400/jts.2013.18.2.131] REFERENCESAl-Kaisi and X Yin. 2005. Tillage and crop residue effects on soil carbon dioxide emission in corn- soybean rotation. J Environ Qual 34: 437-445. Pub Med. Barak P, BO Jobe, AR Krueger, LA Peterson and DA Laird. 1997. Effects of long-term soilacidification due to nitrogen inputs in Wisconsin. Plant Soil 197: 61-69.Blake GR and KH Hartge. 1986. Bulk density. In: A Klute (ed). Methods of Soil Analysis. ASA and SSSA. 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Education in Oceania continues to reflect the embedded implicit and explicit colonial practices and processes from the past. This paper conceptualises a cultural approach to education and leadership appropriate and relevant to the Republic of the Marshall Islands. As elementary school leaders, we highlight Kanne Lobal, a traditional Marshallese navigation practice based on indigenous language, values and practices. We conceptualise and develop Kanne Lobal in this paper as a framework for understanding the usefulness of our indigenous knowledge in leadership and educational practices within formal education. Through bwebwenato, a method of talk story, our key learnings and reflexivities were captured. We argue that realising the value of Marshallese indigenous knowledge and practices for school leaders requires purposeful training of the ways in which our knowledge can be made useful in our professional educational responsibilities. Drawing from our Marshallese knowledge is an intentional effort to inspire, empower and express what education and leadership partnership means for Marshallese people, as articulated by Marshallese themselves. Introduction As noted in the call for papers within the Waikato Journal of Education (WJE) for this special issue, bodies of knowledge and histories in Oceania have long sustained generations across geographic boundaries to ensure cultural survival. For Marshallese people, we cannot really know ourselves “until we know how we came to be where we are today” (Walsh, Heine, Bigler & Stege, 2012). Jitdam Kapeel is a popular Marshallese concept and ideal associated with inquiring into relationships within the family and community. In a similar way, the practice of relating is about connecting the present and future to the past. Education and leadership partnerships are linked and we look back to the past, our history, to make sense and feel inspired to transform practices that will benefit our people. In this paper and in light of our next generation, we reconnect with our navigation stories to inspire and empower education and leadership. Kanne lobal is part of our navigation stories, a conceptual framework centred on cultural practices, values, and concepts that embrace collective partnerships. Our link to this talanoa vā with others in the special issue is to attempt to make sense of connections given the global COVID-19 context by providing a Marshallese approach to address the physical and relational “distance” between education and leadership partnerships in Oceania. Like the majority of developing small island nations in Oceania, the Republic of the Marshall Islands (RMI) has had its share of educational challenges through colonial legacies of the past which continues to drive education systems in the region (Heine, 2002). The historical administration and education in the RMI is one of colonisation. Successive administrations by the Spanish, German, Japanese, and now the US, has resulted in education and learning that privileges western knowledge and forms of learning. This paper foregrounds understandings of education and learning as told by the voices of elementary school leaders from the RMI. The move to re-think education and leadership from Marshallese perspectives is an act of shifting the focus of bwebwenato or conversations that centres on Marshallese language and worldviews. The concept of jelalokjen was conceptualised as traditional education framed mainly within the community context. In the past, jelalokjen was practiced and transmitted to the younger generation for cultural continuity. During the arrival of colonial administrations into the RMI, jelalokjen was likened to the western notions of education and schooling (Kupferman, 2004). Today, the primary function of jelalokjen, as traditional and formal education, it is for “survival in a hostile [and challenging] environment” (Kupferman, 2004, p. 43). Because western approaches to learning in the RMI have not always resulted in positive outcomes for those engaged within the education system, as school leaders who value our cultural knowledge and practices, and aspire to maintain our language with the next generation, we turn to Kanne Lobal, a practice embedded in our navigation stories, collective aspirations, and leadership. The significance in the development of Kanne Lobal, as an appropriate framework for education and leadership, resulted in us coming together and working together. Not only were we able to share our leadership concerns, however, the engagement strengthened our connections with each other as school leaders, our communities, and the Public Schooling System (PSS). Prior to that, many of us were in competition for resources. Educational Leadership: IQBE and GCSL Leadership is a valued practice in the RMI. Before the IQBE programme started in 2018, the majority of the school leaders on the main island of Majuro had not engaged in collaborative partnerships with each other before. Our main educational purpose was to achieve accreditation from the Western Association of Schools and Colleges (WASC), an accreditation commission for schools in the United States. The WASC accreditation dictated our work and relationships and many school leaders on Majuro felt the pressure of competition against each other. We, the authors in this paper, share our collective bwebwenato, highlighting our school leadership experiences and how we gained strength from our own ancestral knowledge to empower “us”, to collaborate with each other, our teachers, communities, as well as with PSS; a collaborative partnership we had not realised in the past. The paucity of literature that captures Kajin Majol (Marshallese language) and education in general in the RMI is what we intend to fill by sharing our reflections and experiences. To move our educational practices forward we highlight Kanne Lobal, a cultural approach that focuses on our strengths, collective social responsibilities and wellbeing. For a long time, there was no formal training in place for elementary school leaders. School principals and vice principals were appointed primarily on their academic merit through having an undergraduate qualification. As part of the first cohort of fifteen school leaders, we engaged in the professional training programme, the Graduate Certificate in School Leadership (GCSL), refitted to our context after its initial development in the Solomon Islands. GCSL was coordinated by the Institute of Education (IOE) at the University of the South Pacific (USP). GCSL was seen as a relevant and appropriate training programme for school leaders in the RMI as part of an Asia Development Bank (ADB) funded programme which aimed at “Improving Quality Basic Education” (IQBE) in parts of the northern Pacific. GCSL was managed on Majuro, RMI’s main island, by the director at the time Dr Irene Taafaki, coordinator Yolanda McKay, and administrators at the University of the South Pacific’s (USP) RMI campus. Through the provision of GCSL, as school leaders we were encouraged to re-think and draw-from our own cultural repository and connect to our ancestral knowledge that have always provided strength for us. This kind of thinking and practice was encouraged by our educational leaders (Heine, 2002). We argue that a culturally-affirming and culturally-contextual framework that reflects the lived experiences of Marshallese people is much needed and enables the disruption of inherent colonial processes left behind by Western and Eastern administrations which have influenced our education system in the RMI (Heine, 2002). Kanne Lobal, an approach utilising a traditional navigation has warranted its need to provide solutions for today’s educational challenges for us in the RMI. Education in the Pacific Education in the Pacific cannot be understood without contextualising it in its history and culture. It is the same for us in the RMI (Heine, 2002; Walsh et al., 2012). The RMI is located in the Pacific Ocean and is part of Micronesia. It was named after a British captain, John Marshall in the 1700s. The atolls in the RMI were explored by the Spanish in the 16th century. Germany unsuccessfully attempted to colonize the islands in 1885. Japan took control in 1914, but after several battles during World War II, the US seized the RMI from them. In 1947, the United Nations made the island group, along with the Mariana and Caroline archipelagos, a U.S. trust territory (Walsh et al, 2012). Education in the RMI reflects the colonial administrations of Germany, Japan, and now the US. Before the turn of the century, formal education in the Pacific reflected western values, practices, and standards. Prior to that, education was informal and not binded to formal learning institutions (Thaman, 1997) and oral traditions was used as the medium for transmitting learning about customs and practices living with parents, grandparents, great grandparents. As alluded to by Jiba B. Kabua (2004), any “discussion about education is necessarily a discussion of culture, and any policy on education is also a policy of culture” (p. 181). It is impossible to promote one without the other, and it is not logical to understand one without the other. Re-thinking how education should look like, the pedagogical strategies that are relevant in our classrooms, the ways to engage with our parents and communities - such re-thinking sits within our cultural approaches and frameworks. Our collective attempts to provide a cultural framework that is relevant and appropriate for education in our context, sits within the political endeavour to decolonize. This means that what we are providing will not only be useful, but it can be used as a tool to question and identify whether things in place restrict and prevent our culture or whether they promote and foreground cultural ideas and concepts, a significant discussion of culture linked to education (Kabua, 2004). Donor funded development aid programmes were provided to support the challenges within education systems. Concerned with the persistent low educational outcomes of Pacific students, despite the prevalence of aid programmes in the region, in 2000 Pacific educators and leaders with support from New Zealand Aid (NZ Aid) decided to intervene (Heine, 2002; Taufe’ulungaki, 2014). In April 2001, a group of Pacific educators and leaders across the region were invited to a colloquium funded by the New Zealand Overseas Development Agency held in Suva Fiji at the University of the South Pacific. The main purpose of the colloquium was to enable “Pacific educators to re-think the values, assumptions and beliefs underlying [formal] schooling in Oceania” (Benson, 2002). Leadership, in general, is a valued practice in the RMI (Heine, 2002). Despite education leadership being identified as a significant factor in school improvement (Sanga & Chu, 2009), the limited formal training opportunities of school principals in the region was a persistent concern. As part of an Asia Development Bank (ADB) funded project, the Improve Quality Basic Education (IQBE) intervention was developed and implemented in the RMI in 2017. Mentoring is a process associated with the continuity and sustainability of leadership knowledge and practices (Sanga & Chu, 2009). It is a key aspect of building capacity and capabilities within human resources in education (ibid). Indigenous knowledges and education research According to Hilda Heine, the relationship between education and leadership is about understanding Marshallese history and culture (cited in Walsh et al., 2012). It is about sharing indigenous knowledge and histories that “details for future generations a story of survival and resilience and the pride we possess as a people” (Heine, cited in Walsh et al., 2012, p. v). This paper is fuelled by postcolonial aspirations yet is grounded in Pacific indigenous research. This means that our intentions are driven by postcolonial pursuits and discourses linked to challenging the colonial systems and schooling in the Pacific region that privileges western knowledge and learning and marginalises the education practices and processes of local people (Thiong’o, 1986). A point of difference and orientation from postcolonialism is a desire to foreground indigenous Pacific language, specifically Majin Majol, through Marshallese concepts. Our collective bwebwenato and conversation honours and values kautiej (respect), jouj eo mour eo (reciprocity), and jouj (kindness) (Taafaki & Fowler, 2019). Pacific leaders developed the Rethinking Pacific Education Initiative for and by Pacific People (RPEIPP) in 2002 to take control of the ways in which education research was conducted by donor funded organisations (Taufe’ulungaki, 2014). Our former president, Dr Hilda Heine was part of the group of leaders who sought to counter the ways in which our educational and leadership stories were controlled and told by non-Marshallese (Heine, 2002). As a former minister of education in the RMI, Hilda Heine continues to inspire and encourage the next generation of educators, school leaders, and researchers to re-think and de-construct the way learning and education is conceptualised for Marshallese people. The conceptualisation of Kanne Lobal acknowledges its origin, grounded in Marshallese navigation knowledge and practice. Our decision to unpack and deconstruct Kanne Lobal within the context of formal education and leadership responds to the need to not only draw from indigenous Marshallese ideas and practice but to consider that the next generation will continue to be educated using western processes and initiatives particularly from the US where we get a lot of our funding from. According to indigenous researchers Dawn Bessarab and Bridget Ng’andu (2010), doing research that considers “culturally appropriate processes to engage with indigenous groups and individuals is particularly pertinent in today’s research environment” (p. 37). Pacific indigenous educators and researchers have turned to their own ancestral knowledge and practices for inspiration and empowerment. Within western research contexts, the often stringent ideals and processes are not always encouraging of indigenous methods and practices. However, many were able to ground and articulate their use of indigenous methods as being relevant and appropriate to capturing the realities of their communities (Nabobo-Baba, 2008; Sualii-Sauni & Fulu-Aiolupotea, 2014; Thaman, 1997). At the same time, utilising Pacific indigenous methods and approaches enabled research engagement with their communities that honoured and respected them and their communities. For example, Tongan, Samoan, and Fijian researchers used the talanoa method as a way to capture the stories, lived realities, and worldviews of their communities within education in the diaspora (Fa’avae, Jones, & Manu’atu, 2016; Nabobo-Baba, 2008; Sualii-Sauni & Aiolupotea, 2014; Vaioleti, 2005). Tok stori was used by Solomon Islander educators and school leaders to highlight the unique circles of conversational practice and storytelling that leads to more positive engagement with their community members, capturing rich and meaningful narratives as a result (Sanga & Houma, 2004). The Indigenous Aborigine in Australia utilise yarning as a “relaxed discussion through which both the researcher and participant journey together visiting places and topics of interest relevant” (Bessarab & Ng’andu, 2010, p. 38). Despite the diverse forms of discussions and storytelling by indigenous peoples, of significance are the cultural protocols, ethics, and language for conducting and guiding the engagement (Bessarab & Ng’andu, 2010; Nabobo-Baba, 2008; Sualii-Sauni & Aiolupotea, 2014). Through the ethics, values, protocols, and language, these are what makes indigenous methods or frameworks unique compared to western methods like in-depth interviews or semi-structured interviews. This is why it is important for us as Marshallese educators to frame, ground, and articulate how our own methods and frameworks of learning could be realised in western education (Heine, 2002; Jetnil-Kijiner, 2014). In this paper, we utilise bwebwenato as an appropriate method linked to “talk story”, capturing our collective stories and experiences during GCSL and how we sought to build partnerships and collaboration with each other, our communities, and the PSS. Bwebwenato and drawing from Kajin Majel Legends and stories that reflect Marshallese society and its cultural values have survived through our oral traditions. The practice of weaving also holds knowledge about our “valuable and earliest sources of knowledge” (Taafaki & Fowler, 2019, p. 2). The skilful navigation of Marshallese wayfarers on the walap (large canoes) in the ocean is testament of their leadership and the value they place on ensuring the survival and continuity of Marshallese people (Taafaki & Fowler, 2019; Walsh et al., 2012). During her graduate study in 2014, Kathy Jetnil-Kijiner conceptualised bwebwenato as being the most “well-known form of Marshallese orality” (p. 38). The Marshallese-English dictionary defined bwebwenato as talk, conversation, story, history, article, episode, lore, myth, or tale (cited in Jetnil Kijiner, 2014). Three years later in 2017, bwebwenato was utilised in a doctoral project by Natalie Nimmer as a research method to gather “talk stories” about the experiences of 10 Marshallese experts in knowledge and skills ranging from sewing to linguistics, canoe-making and business. Our collective bwebwenato in this paper centres on Marshallese ideas and language. The philosophy of Marshallese knowledge is rooted in our “Kajin Majel”, or Marshallese language and is shared and transmitted through our oral traditions. For instance, through our historical stories and myths. Marshallese philosophy, that is, the knowledge systems inherent in our beliefs, values, customs, and practices are shared. They are inherently relational, meaning that knowledge systems and philosophies within our world are connected, in mind, body, and spirit (Jetnil-Kijiner, 2014; Nimmer, 2017). Although some Marshallese believe that our knowledge is disappearing as more and more elders pass away, it is therefore important work together, and learn from each other about the knowledges shared not only by the living but through their lamentations and stories of those who are no longer with us (Jetnil-Kijiner, 2014). As a Marshallese practice, weaving has been passed-down from generation to generation. Although the art of weaving is no longer as common as it used to be, the artefacts such as the “jaki-ed” (clothing mats) continue to embody significant Marshallese values and traditions. For our weavers, the jouj (check spelling) is the centre of the mat and it is where the weaving starts. When the jouj is correct and weaved well, the remainder and every other part of the mat will be right. The jouj is symbolic of the “heart” and if the heart is prepared well, trained well, then life or all other parts of the body will be well (Taafaki & Fowler, 2019). In that light, we have applied the same to this paper. Conceptualising and drawing from cultural practices that are close and dear to our hearts embodies a significant ontological attempt to prioritize our own knowledge and language, a sense of endearment to who we are and what we believe education to be like for us and the next generation. The application of the phrase “Majolizing '' was used by the Ministry of Education when Hilda Heine was minister, to weave cultural ideas and language into the way that teachers understand the curriculum, develop lesson plans and execute them in the classroom. Despite this, there were still concerns with the embedded colonized practices where teachers defaulted to eurocentric methods of doing things, like the strategies provided in the textbooks given to us. In some ways, our education was slow to adjust to the “Majolizing '' intention by our former minister. In this paper, we provide Kanne Lobal as a way to contribute to the “Majolizing intention” and perhaps speed up yet still be collectively responsible to all involved in education. Kajin Wa and Kanne Lobal “Wa” is the Marshallese concept for canoe. Kajin wa, as in canoe language, has a lot of symbolic meaning linked to deeply-held Marshallese values and practices. The canoe was the foundational practice that supported the livelihood of harsh atoll island living which reflects the Marshallese social world. The experts of Kajin wa often refer to “wa” as being the vessel of life, a means and source of sustaining life (Kelen, 2009, cited in Miller, 2010). “Jouj” means kindness and is the lower part of the main hull of the canoe. It is often referred to by some canoe builders in the RMI as the heart of the canoe and is linked to love. The jouj is one of the first parts of the canoe that is built and is “used to do all other measurements, and then the rest of the canoe is built on top of it” (Miller, 2010, p. 67). The significance of the jouj is that when the canoe is in the water, the jouj is the part of the hull that is underwater and ensures that all the cargo and passengers are safe. For Marshallese, jouj or kindness is what living is about and is associated with selflessly carrying the responsibility of keeping the family and community safe. The parts of the canoe reflect Marshallese culture, legend, family, lineage, and kinship. They embody social responsibilities that guide, direct, and sustain Marshallese families’ wellbeing, from atoll to atoll. For example, the rojak (boom), rojak maan (upper boom), rojak kōrā (lower boom), and they support the edges of the ujelā/ujele (sail) (see figure 1). The literal meaning of rojak maan is male boom and rojak kōrā means female boom which together strengthens the sail and ensures the canoe propels forward in a strong yet safe way. Figuratively, the rojak maan and rojak kōrā symbolise the mother and father relationship which when strong, through the jouj (kindness and love), it can strengthen families and sustain them into the future. Figure 1. Parts of the canoe Source: https://www.canoesmarshallislands.com/2014/09/names-of-canoe-parts/ From a socio-cultural, communal, and leadership view, the canoe (wa) provides understanding of the relationships required to inspire and sustain Marshallese peoples’ education and learning. We draw from Kajin wa because they provide cultural ideas and practices that enable understanding of education and leadership necessary for sustaining Marshallese people and realities in Oceania. When building a canoe, the women are tasked with the weaving of the ujelā/ujele (sail) and to ensure that it is strong enough to withstand long journeys and the fierce winds and waters of the ocean. The Kanne Lobal relates to the front part of the ujelā/ujele (sail) where the rojak maan and rojak kōrā meet and connect (see the red lines in figure 1). Kanne Lobal is linked to the strategic use of the ujelā/ujele by navigators, when there is no wind north wind to propel them forward, to find ways to capture the winds so that their journey can continue. As a proverbial saying, Kanne Lobal is used to ignite thinking and inspire and transform practice particularly when the journey is rough and tough. In this paper we draw from Kanne Lobal to ignite, inspire, and transform our educational and leadership practices, a move to explore what has always been meaningful to Marshallese people when we are faced with challenges. The Kanne Lobal utilises our language, and cultural practices and values by sourcing from the concepts of jouj (kindness, love), kautiej (respect), and jouj eo mour eo (reciprocity). A key Marshallese proverb, “Enra bwe jen lale rara”, is the cultural practice where families enact compassion through the sharing of food in all occurrences. The term “enra” is a small basket weaved from the coconut leaves, and often used by Marshallese as a plate to share and distribute food amongst each other. Bwe-jen-lale-rara is about noticing and providing for the needs of others, and “enra” the basket will help support and provide for all that are in need. “Enra-bwe-jen-lale-rara” is symbolic of cultural exchange and reciprocity and the cultural values associated with building and maintaining relationships, and constantly honouring each other. As a Marshallese practice, in this article we share our understanding and knowledge about the challenges as well as possible solutions for education concerns in our nation. In addition, we highlight another proverb, “wa kuk wa jimor”, which relates to having one canoe, and despite its capacity to feed and provide for the individual, but within the canoe all people can benefit from what it can provide. In the same way, we provide in this paper a cultural framework that will enable all educators to benefit from. It is a framework that is far-reaching and relevant to the lived realities of Marshallese people today. Kumit relates to people united to build strength, all co-operating and working together, living in peace, harmony, and good health. Kanne Lobal: conceptual framework for education and leadership An education framework is a conceptual structure that can be used to capture ideas and thinking related to aspects of learning. Kanne Lobal is conceptualised and framed in this paper as an educational framework. Kanne Lobal highlights the significance of education as a collective partnership whereby leadership is an important aspect. Kanne Lobal draws-from indigenous Marshallese concepts like kautiej (respect), jouj eo mour eo (reciprocity), and jouj (kindness, heart). The role of a leader, including an education leader, is to prioritise collective learning and partnerships that benefits Marshallese people and the continuity and survival of the next generation (Heine, 2002; Thaman, 1995). As described by Ejnar Aerōk, an expert canoe builder in the RMI, he stated: “jerbal ippān doon bwe en maron maan wa e” (cited in Miller, 2010, p. 69). His description emphasises the significance of partnerships and working together when navigating and journeying together in order to move the canoe forward. The kubaak, the outrigger of the wa (canoe) is about “partnerships”. For us as elementary school leaders on Majuro, kubaak encourages us to value collaborative partnerships with each other as well as our communities, PSS, and other stakeholders. Partnerships is an important part of the Kanne Lobal education and leadership framework. It requires ongoing bwebwenato – the inspiring as well as confronting and challenging conversations that should be mediated and negotiated if we and our education stakeholders are to journey together to ensure that the educational services we provide benefits our next generation of young people in the RMI. Navigating ahead the partnerships, mediation, and negotiation are the core values of jouj (kindness, love), kautiej (respect), and jouj eo mour eo (reciprocity). As an organic conceptual framework grounded in indigenous values, inspired through our lived experiences, Kanne Lobal provides ideas and concepts for re-thinking education and leadership practices that are conducive to learning and teaching in the schooling context in the RMI. By no means does it provide the solution to the education ills in our nation. However, we argue that Kanne Lobal is a more relevant approach which is much needed for the negatively stigmatised system as a consequence of the various colonial administrations that have and continue to shape and reframe our ideas about what education should be like for us in the RMI. Moreover, Kannel Lobal is our attempt to decolonize the framing of education and leadership, moving our bwebwenato to re-framing conversations of teaching and learning so that our cultural knowledge and values are foregrounded, appreciated, and realised within our education system. Bwebwenato: sharing our stories In this section, we use bwebwenato as a method of gathering and capturing our stories as data. Below we capture our stories and ongoing conversations about the richness in Marshallese cultural knowledge in the outer islands and on Majuro and the potentialities in Kanne Lobal. Danny Jim When I was in third grade (9-10 years of age), during my grandfather’s speech in Arno, an atoll near Majuro, during a time when a wa (canoe) was being blessed and ready to put the canoe into the ocean. My grandfather told me the canoe was a blessing for the family. “Without a canoe, a family cannot provide for them”, he said. The canoe allows for travelling between places to gather food and other sources to provide for the family. My grandfather’s stories about people’s roles within the canoe reminded me that everyone within the family has a responsibility to each other. Our women, mothers and daughters too have a significant responsibility in the journey, in fact, they hold us, care for us, and given strength to their husbands, brothers, and sons. The wise man or elder sits in the middle of the canoe, directing the young man who help to steer. The young man, he does all the work, directed by the older man. They take advice and seek the wisdom of the elder. In front of the canoe, a young boy is placed there and because of his strong and youthful vision, he is able to help the elder as well as the young man on the canoe. The story can be linked to the roles that school leaders, teachers, and students have in schooling. Without each person knowing intricately their role and responsibility, the sight and vision ahead for the collective aspirations of the school and the community is difficult to comprehend. For me, the canoe is symbolic of our educational journey within our education system. As the school leader, a central, trusted, and respected figure in the school, they provide support for teachers who are at the helm, pedagogically striving to provide for their students. For without strong direction from the school leaders and teachers at the helm, the students, like the young boy, cannot foresee their futures, or envisage how education can benefit them. This is why Kanne Lobal is a significant framework for us in the Marshall Islands because within the practice we are able to take heed and empower each other so that all benefit from the process. Kanne Lobal is linked to our culture, an essential part of who we are. We must rely on our own local approaches, rather than relying on others that are not relevant to what we know and how we live in today’s society. One of the things I can tell is that in Majuro, compared to the outer islands, it’s different. In the outer islands, parents bring children together and tell them legends and stories. The elders tell them about the legends and stories – the bwebwenato. Children from outer islands know a lot more about Marshallese legends compared to children from the Majuro atoll. They usually stay close to their parents, observe how to prepare food and all types of Marshallese skills. Loretta Joseph Case There is little Western influence in the outer islands. They grow up learning their own culture with their parents, not having tv. They are closely knit, making their own food, learning to weave. They use fire for cooking food. They are more connected because there are few of them, doing their own culture. For example, if they’re building a house, the ladies will come together and make food to take to the males that are building the house, encouraging them to keep on working - “jemjem maal” (sharpening tools i.e. axe, like encouraging workers to empower them). It’s when they bring food and entertainment. Rubon Rubon Togetherness, work together, sharing of food, these are important practices as a school leader. Jemjem maal – the whole village works together, men working and the women encourage them with food and entertainment. All the young children are involved in all of the cultural practices, cultural transmission is consistently part of their everyday life. These are stronger in the outer islands. Kanne Lobal has the potential to provide solutions using our own knowledge and practices. Connie Joel When new teachers become a teacher, they learn more about their culture in teaching. Teaching raises the question, who are we? A popular saying amongst our people, “Aelon kein ad ej aelon in manit”, means that “Our islands are cultural islands”. Therefore, when we are teaching, and managing the school, we must do this culturally. When we live and breathe, we must do this culturally. There is more socialising with family and extended family. Respect the elderly. When they’re doing things the ladies all get together, in groups and do it. Cut the breadfruit, and preserve the breadfruit and pandanus. They come together and do it. Same as fishing, building houses, building canoes. They use and speak the language often spoken by the older people. There are words that people in the outer islands use and understand language regularly applied by the elderly. Respect elderly and leaders more i.e., chiefs (iroj), commoners (alap), and the workers on the land (ri-jerbal) (social layer under the commoners). All the kids, they gather with their families, and go and visit the chiefs and alap, and take gifts from their land, first produce/food from the plantation (eojōk). Tommy Almet The people are more connected to the culture in the outer islands because they help one another. They don’t have to always buy things by themselves, everyone contributes to the occasion. For instance, for birthdays, boys go fishing, others contribute and all share with everyone. Kanne Lobal is a practice that can bring people together – leaders, teachers, stakeholders. We want our colleagues to keep strong and work together to fix problems like students and teachers’ absenteeism which is a big problem for us in schools. Demetria Malachi The culture in the outer islands are more accessible and exposed to children. In Majuro, there is a mixedness of cultures and knowledges, influenced by Western thinking and practices. Kanne Lobal is an idea that can enhance quality educational purposes for the RMI. We, the school leaders who did GCSL, we want to merge and use this idea because it will help benefit students’ learning and teachers’ teaching. Kanne Lobal will help students to learn and teachers to teach though traditional skills and knowledge. We want to revitalize our ways of life through teaching because it is slowly fading away. Also, we want to have our own Marshallese learning process because it is in our own language making it easier to use and understand. Essentially, we want to proudly use our own ways of teaching from our ancestors showing the appreciation and blessings given to us. Way Forward To think of ways forward is about reflecting on the past and current learnings. Instead of a traditional discussion within a research publication, we have opted to continue our bwebwenato by sharing what we have learnt through the Graduate Certificate in School Leadership (GCSL) programme. Our bwebwenato does not end in this article and this opportunity to collaborate and partner together in this piece of writing has been a meaningful experience to conceptualise and unpack the Kanne Lobal framework. Our collaborative bwebwenato has enabled us to dig deep into our own wise knowledges for guidance through mediating and negotiating the challenges in education and leadership (Sanga & Houma, 2004). For example, bwe-jen-lale-rara reminds us to inquire, pay attention, and focus on supporting the needs of others. Through enra-bwe-jen-lale-rara, it reminds us to value cultural exchange and reciprocity which will strengthen the development and maintaining of relationships based on ways we continue to honour each other (Nimmer, 2017). We not only continue to support each other, but also help mentor the next generation of school leaders within our education system (Heine, 2002). Education and leadership are all about collaborative partnerships (Sanga & Chu, 2009; Thaman, 1997). Developing partnerships through the GCSL was useful learning for us. It encouraged us to work together, share knowledge, respect each other, and be kind. The values of jouj (kindness, love), kautiej (respect), and jouj eo mour eo (reciprocity) are meaningful in being and becoming and educational leader in the RMI (Jetnil-Kijiner, 2014; Miller, 2010; Nimmer, 2017). These values are meaningful for us practice particularly given the drive by PSS for schools to become accredited. The workshops and meetings delivered during the GCSL in the RMI from 2018 to 2019 about Kanne Lobal has given us strength to share our stories and experiences from the meeting with the stakeholders. But before we met with the stakeholders, we were encouraged to share and speak in our language within our courses: EDP05 (Professional Development and Learning), EDP06 (School Leadership), EDP07 (School Management), EDP08 (Teaching and Learning), and EDP09 (Community Partnerships). In groups, we shared our presentations with our peers, the 15 school leaders in the GCSL programme. We also invited USP RMI staff. They liked the way we presented Kannel Lobal. They provided us with feedback, for example: how the use of the sail on the canoe, the parts and their functions can be conceptualised in education and how they are related to the way that we teach our own young people. Engaging stakeholders in the conceptualisation and design stages of Kanne Lobal strengthened our understanding of leadership and collaborative partnerships. Based on various meetings with the RMI Pacific Resources for Education and Learning (PREL) team, PSS general assembly, teachers from the outer islands, and the PSS executive committee, we were able to share and receive feedback on the Kanne Lobal framework. The coordinators of the PREL programme in the RMI were excited by the possibilities around using Kanne Lobal, as a way to teach culture in an inspirational way to Marshallese students. Our Marshallese knowledge, particularly through the proverbial meaning of Kanne Lobal provided so much inspiration and insight for the groups during the presentation which gave us hope and confidence to develop the framework. Kanne Lobal is an organic and indigenous approach, grounded in Marshallese ways of doing things (Heine, 2002; Taafaki & Fowler, 2019). Given the persistent presence of colonial processes within the education system and the constant reference to practices and initiatives from the US, Kanne Lobal for us provides a refreshing yet fulfilling experience and makes us feel warm inside because it is something that belongs to all Marshallese people. Conclusion Marshallese indigenous knowledge and practices provide meaningful educational and leadership understanding and learnings. They ignite, inspire, and transform thinking and practice. The Kanne Lobal conceptual framework emphasises key concepts and values necessary for collaborative partnerships within education and leadership practices in the RMI. The bwebwenato or talk stories have been insightful and have highlighted the strengths and benefits that our Marshallese ideas and practices possess when looking for appropriate and relevant ways to understand education and leadership. 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Streams and rivers are globally threatened ecosystems because of increasing levels of exploitation, habitat degradation and other anthropogenic pressures. In the Lake Victoria Basin (LVB) in East Africa, these threats are mostly caused by unsustainable land use; however, the monitoring of ecological integrity of river systems has been hampered by a lack of locally developed indices. This study assessed the health of four rivers (Nzoia, Nyando, Sondu–Miriu and Mara) on the Kenyan side of the LVB using physicochemical water quality parameters and a fish-based index of biotic integrity (IBI). Fish tolerance ranking was derived from principal component analysis of water quality parameters, and the concept of niche breadth (NB). The relationship between fish species and water quality parameters was examined with canonical correspondence analysis, whereas community metrics and stressors were evaluated through Pearson network correlation analysis. Fish species richness, trophic structures, taxonomic composition and species tolerance were used to generate the metrics for fish-based IBI. NB showed that most of the fish species were moderately tolerant to poor water. Moderately tolerant and intolerant fish species were negatively correlated with a high level of organic loading in the Mara River. Fish-based IBI scores for the rivers ranged from 26 to 34, with Sondu–Miriu scoring the lowest. Our results show that the cumulative effect of stressors can adequately rank fish species tolerance according to the disturbance gradients and further develop regional metrics to assess river health. Despite the fact that fish communities are declining, continual management and enforcement of environmental regulations are important, with conservation and management of headwaters and low-order streams being essential while they are still species rich.

Factors influencing the spatio-temporal dynamics of plankton communities in small tropical lakes are not well-understood. This study assessed plankton communities in response to spatial (six sampling sites) and seasonal (wet vs. dry seasons) changes in environmental variables in Lake Kanyaboli, a small satellite lake on the northern shores of Lake Victoria, Kenya. Water quality variables, including pH, conductivity (EC), dissolved oxygen (DO), temperature, Secchi depth (SD), nitrates (NO3-), nitrites (NO2-), ammonium (NH4+), soluble reactive phosphorus (SRP), total nitrogen (TN), total phosphorus (TP), and chlorophyll-a (Chl-a), were monitored monthly at six sites spread throughout the lake for 1 year. Phytoplankton and zooplankton samples were collected and analyzed for taxon composition and abundance. Two-way ANOVA showed no significant interaction between site and season for all variables. Likewise, there were no significant spatial differences for all variables except Chl- a. A t-test showed significant seasonal differences in SD, DO, NH4+, NO3-, NO2-, and TN. Thirty phytoplankton genera were identified belonging to Bacillariophyceae, Chlorophyceae, Cryptophyceae, Cyanophyceae, Euglenoidae, Trebouxiophyceae, and Zygnematophyceae, with Chlorophyceae being the most dominant (42.30%). Zooplankton comprised of 15 genera, belonging to Copepoda (55.4%), Rotifera (27.9%), and Cladocera (16.7%). Two-way ANOVA for plankton abundance showed no significant interaction between site and season, but there were significant differences in community composition between the wet and dry seasons. Canonical correspondence analysis identified water clarity (Secchi depth) and concentrations of dissolved fractions of nitrogen and phosphorus as the major water quality variables driving variation in the composition of plankton communities in the lake. This study showed that seasonality was a major driver of changes in plankton community composition between dry and wet seasons through changes in the concentrations of nutrients (NH4+, NO3-, NO2-, TN, and TP). Lake Kanyaboli's phytoplankton community indicated a non-equilibrial state, perhaps due to short residence times of water, especially during the wet season, and dense macrophytes fringing the lake that increase nutrient uptake and limit the dominance of select phytoplankton species. This study shows the importance of long-term studies covering dry and wet seasons to understand the dynamics of plankton communities and their drivers in small tropical waterbodies to inform management and conservation.