Artículos de revistas: "Dryland river"

1

Petts, Geoff. "Perspective: river science for dryland river regulation". Transactions of the Royal Society of South Australia 141, n.º 2 (3 de julio de 2017): 230–36. http://dx.doi.org/10.1080/03721426.2017.1376774.

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2

Burford, Michele A., Andrew J. Cook, Christine S. Fellows, Stephen R. Balcombe y Stuart E. Bunn. "Sources of carbon fuelling production in an arid floodplain river". Marine and Freshwater Research 59, n.º 3 (2008): 224. http://dx.doi.org/10.1071/mf07159.

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Dryland rivers are characterised by highly pulsed and unpredictable flow, and support a diverse biota. The present study examined the contribution of floodplain sources to the productivity of a disconnected dryland river; that is a waterhole, after a major overland flood event. Rate measures of productivity were combined with stable isotope and biomass data on the food web in the waterhole and floodplain. The present study estimated that 50% of the fish carbon in the waterhole after flooding was derived from floodplain food sources. In the few months after retraction of the river to isolated waterholes, the large biomass of fish concentrated from the flooding decreased by 80%, most likely as a result of starvation. Based on the development of a carbon budget for the waterhole, mass mortality is hypothesised to be the cause of the high rates of heterotrophic production in the waterhole. The present study suggests that floodplain inputs are important for fuelling short-term production in waterholes, but via an unconventional pathway; that is, fish mortality. The episodic nature of flooding in dryland rivers means that changes in flow regimes, such as water regulation or abstraction, will reduce flooding and hence floodplain subsidies to the river. This is likely to have significant impacts on river productivity.

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3

Sandercock, P. J., J. M. Hooke y J. M. Mant. "Vegetation in dryland river channels and its interaction with fluvial processes". Progress in Physical Geography: Earth and Environment 31, n.º 2 (abril de 2007): 107–29. http://dx.doi.org/10.1177/0309133307076106.

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Vegetation forms a major component of the channel environment of dryland rivers in Mediterranean Europe yet the interactions between vegetation and fluvial processes in dryland river channels have received relatively little attention. Characteristic of dryland channels is a degree of complexity and irregularity in morphology coupled with abrupt changes in patterns of riparian vegetation along their course. This is in contrast to more temperate and humid channels, which show strong downstream trends in morphology and a regularity in the distribution of vegetation across the valley floor. The general effect of vegetation in these channels appears to be to enhance the processes of sedimentation and increase resistance to erosion. However, at high stress levels vegetation may be removed. The limited work that has been undertaken indicates that there is considerable variability in the effect that vegetation has on channel processes, depending on both the magnitude of the flow and characteristics of the vegetation, such as their distribution and positioning within the channel and factors such as plant flexibility, cross-sectional area (blockage ratio), number of stems. Studies of sediment connectivity are beginning to yield new insights into the dynamics of dryland rivers, and in particular the role of vegetation in reducing the connectivity of sediment transfers downstream. Detailed surveying at monitored sites such as is being carried out within the EU-funded project RECONDES is required to study the interactions between vegetation, sediment and flow in dryland rivers of the Mediterranean region.

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4

Parsons, Melissa y Mark Southwell. "Flooding and geomorphology influence the persistence of the invasive annual herb Noogoora burr (Xanthium occidentale Bertol.) in the riparian zone of the dryland Darling River, Australia". Rangeland Journal 37, n.º 5 (2015): 433. http://dx.doi.org/10.1071/rj14116.

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The relationship between flooding, and the establishment and persistence of exotic species, is not well understood in highly variable dryland rivers. Increased moisture associated with floods is likely to stimulate establishment and growth of exotic plants, but floods may also act as a stress to exotic plants if floods last for weeks to months. This study examined how physical drivers of dryland rivers – flood inundation and geomorphology – influence the persistence of Xanthium occidentale Bertol. in the dryland Darling River, Australia. The distribution of X. occidentale was associated with flood-related moisture subsidy, moderated by channel geomorphology. Dead stalks and burrs on the ground occurred above the 8-m height of the previous flood. Adult and juvenile plants occurred below 8 m corresponding to smaller flood events. Flatter geomorphic units (floodplains and benches) contained more plants and burrs, whereas steeper geomorphic units (banks) did not retain burrs, limiting plant abundance. Flooding is not a stress to X. occidentale. A glasshouse experiment showed that flood durations of up to 40 days had minimal effect on the germination, survival and growth of X. occidentale burrs, seeds or seedlings. Weed management strategies for X. occidentale in dryland rivers could be enhanced by targeting periods following flooding when moisture availability is increased on the flatter geomorphic units in the river channel.

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5

Lamontagne, S., W. S. Hicks, R. W. Fitzpatrick y S. Rogers. "Sulfidic materials in dryland river wetlands". Marine and Freshwater Research 57, n.º 8 (2006): 775. http://dx.doi.org/10.1071/mf06057.

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Due to a combination of river regulation, dryland salinity and irrigation return, lower River Murray floodplains (Australia) and associated wetlands are undergoing salinisation. It was hypothesised that salinisation would provide suitable conditions for the accumulation of sulfidic materials (soils and sediments enriched in sulfides, such as pyrite) in these wetlands. A survey of nine floodplain wetlands representing a salinity gradient from fresh to hypersaline determined that surface sediment sulfide concentrations varied from <0.05% to ~1%. Saline and permanently flooded wetlands tended to have greater sulfide concentrations than freshwater ones or those with more regular wetting–drying regimes. The acidification risk associated with the sulfidic materials was evaluated using field peroxide oxidations tests and laboratory measurements of net acid generation potential. Although sulfide concentration was elevated in many wetlands, the acidification risk was low because of elevated carbonate concentration (up to 30% as CaCO3) in the sediments. One exception was Bottle Bend Lagoon (New South Wales), which had acidified during a draw-down event in 2002 and was found to have both actual and potential acid sulfate soils at the time of the survey (2003). Potential acid sulfate soils also occurred locally in the hypersaline Loveday Disposal Basin. The other environmental risks associated with sulfidic materials could not be reliably evaluated because no guideline exists to assess them. These include the deoxygenation risk following sediment resuspension and the generation of foul odours during drying events. The remediation of wetland salinity in the Murray–Darling Basin will require that the risks associated with disturbing sulfidic materials during management actions be evaluated.

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6

Walker, K. F., F. Sheldon y J. T. Puckridge. "A perspective on dryland river ecosystems". Regulated Rivers: Research & Management 11, n.º 1 (septiembre de 1995): 85–104. http://dx.doi.org/10.1002/rrr.3450110108.

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7

Costa, A. C., A. Bronstert y J. C. de Araújo. "A channel transmission losses model for different dryland rivers". Hydrology and Earth System Sciences 16, n.º 4 (3 de abril de 2012): 1111–35. http://dx.doi.org/10.5194/hess-16-1111-2012.

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Abstract. Channel transmission losses in drylands take place normally in extensive alluvial channels or streambeds underlain by fractured rocks. They can play an important role in streamflow rates, groundwater recharge, freshwater supply and channel-associated ecosystems. We aim to develop a process-oriented, semi-distributed channel transmission losses model, using process formulations which are suitable for data-scarce dryland environments and applicable to both hydraulically disconnected losing streams and hydraulically connected losing(/gaining) streams. This approach should be able to cover a large variation in climate and hydro-geologic controls, which are typically found in dryland regions of the Earth. Our model was first evaluated for a losing/gaining, hydraulically connected 30 km reach of the Middle Jaguaribe River (MJR), Ceará, Brazil, which drains a catchment area of 20 000 km2. Secondly, we applied it to a small losing, hydraulically disconnected 1.5 km channel reach in the Walnut Gulch Experimental Watershed (WGEW), Arizona, USA. The model was able to predict reliably the streamflow volume and peak for both case studies without using any parameter calibration procedure. We have shown that the evaluation of the hypotheses on the dominant hydrological processes was fundamental for reducing structural model uncertainties and improving the streamflow prediction. For instance, in the case of the large river reach (MJR), it was shown that both lateral stream-aquifer water fluxes and groundwater flow in the underlying alluvium parallel to the river course are necessary to predict streamflow volume and channel transmission losses, the former process being more relevant than the latter. Regarding model uncertainty, it was shown that the approaches, which were applied for the unsaturated zone processes (highly nonlinear with elaborate numerical solutions), are much more sensitive to parameter variability than those approaches which were used for the saturated zone (mathematically simple water budgeting in aquifer columns, including backwater effects). In case of the MJR-application, we have seen that structural uncertainties due to the limited knowledge of the subsurface saturated system interactions (i.e. groundwater coupling with channel water; possible groundwater flow parallel to the river) were more relevant than those related to the subsurface parameter variability. In case of the WEGW application we have seen that the non-linearity involved in the unsaturated flow processes in disconnected dryland river systems (controlled by the unsaturated zone) generally contain far more model uncertainties than do connected systems controlled by the saturated flow. Therefore, the degree of aridity of a dryland river may be an indicator of potential model uncertainty and subsequent attainable predictability of the system.

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8

Balcombe, Stephen R., Angela H. Arthington, Neal D. Foster, Martin C. Thoms, Glenn G. Wilson y Stuart E. Bunn. "Fish assemblages of an Australian dryland river: abundance, assemblage structure and recruitment patterns in the Warrego River, Murray - Darling Basin". Marine and Freshwater Research 57, n.º 6 (2006): 619. http://dx.doi.org/10.1071/mf06025.

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Fish in dryland rivers must cope with extreme variability in hydrology, temperature and other environmental factors that ultimately have a major influence on their patterns of distribution and abundance at the landscape scale. Given that fish persist in these systems under conditions of high environmental variability, dryland rivers represent ideal systems to investigate the processes contributing to and sustaining fish biodiversity and recruitment in variable environments. Hence, spatial and temporal variation in fish assemblage structure was examined in 15 waterholes of the Warrego River between October 2001 and May 2003. Fish assemblages in isolated waterholes were differentiated at the end of the dry 2001 winter but were relatively similar following high summer flows in January 2002 as a consequence of high hydrological connectivity among waterholes. Small, shallow waterholes supported more species and higher abundances than large-deep waterholes. Large, deep waterholes provided important refuge for large-bodied fish species such as adult yellowbelly, Macquaria ambigua, and the eel-tailed catfish, Tandanus tandanus. Recruitment patterns of bony bream (Nematalosa erebi), Hyrtl’s tandan (Neosilurus hyrtlii) and yellowbelly were associated with high flow events and backwater inundation; however recruitment of yellowbelly and bony bream was also evident following a zero-flow period. Departures from typical flood-induced seasonal spawning patterns may reflect opportunistic spawning behaviours appropriate to the erratic patterns of flooding and dry spells in dryland rivers.

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9

Fellows, C. S., M. L. Wos, P. C. Pollard y S. E. Bunn. "Ecosystem metabolism in a dryland river waterhole". Marine and Freshwater Research 58, n.º 3 (2007): 250. http://dx.doi.org/10.1071/mf06142.

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Little is known about ecosystem processes in dryland rivers, despite the global distribution of these systems. Those in Australia are characterised by long periods of no flow in which they persist for many months as series of isolated, often turbid, waterholes. We assessed benthic and pelagic primary production, respiration, and bacterial production in one of these waterholes to determine the metabolic balance of the waterhole and resolve the relative importance of autochthonous and allochthonous sources of organic carbon. Despite a photic zone depth of only 0.25 m, three lines of evidence suggested that autochthonous sources of organic carbon were important for fuelling bacterial production under no-flow conditions: the metabolic balance of the waterhole was not indicative of large allochthonous inputs; rates of gross primary production were great enough to meet a substantial fraction of estimated bacterial carbon demand; and pathways for allochthonous carbon to enter the waterhole were limited. These results suggest that models of lake metabolism based on temperate ecosystems can be expanded to include dryland river waterholes, which group with eutrophic lakes owing to their high levels of inorganic nutrients, low allochthonous inputs and autotrophic metabolic balance.

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10

Wan, Wenhua, Hang Zheng, Yueyi Liu, Jianshi Zhao, Yingqi Fan y Hongbo Fan. "Ecological Compensation Mechanism in a Trans-Provincial River Basin: A Hydrological/Water-Quality Modeling-Based Analysis". Water 14, n.º 16 (18 de agosto de 2022): 2542. http://dx.doi.org/10.3390/w14162542.

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Ecological compensation is an important economic means of water pollution control and quality management, especially for trans-regional rivers with unbalanced economic and social development between upstream and downstream. The Tangbai River Basin (TRB), a watershed crossing Henan province and Hubei province, China, forms one of the nation’s most productive agricultural regions. The TRB has been exposed to high doses of fertilizers for a long time. This study simulates hydrologic and nutrient cycling in the TRB using Soil and Water Assessment Tool (SWAT) with limited data available. The results indicate that dryland fields, which constitute 62% of the basin area, produce 80% of total nitrogen (TN) and 85% of total phosphorus (TP) yields of the whole river basin. The water quality of river sections at the provincial boundary shows that only 29% of the time from 2000 to 2019 met the Class III standard regarding TN and TP concentrations, and the concentrations in the spring flood season are approximately three times the mean in the non-flood season. The Grain for Green ecological restoration measure in Henan province shows that restoration of non-flat drylands can reduce nutrient loads at trans-provincial sections by 3.5 times compared to that of slope-independent drylands; however, the water quality compliance rate remains similar. The value of ecological compensation can also vary widely depending on different quantitative criteria. The SWAT-based pollutant quantification method adopted in this study could have implications for ecological compensation in trans-regional rivers.

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11

Tooth, Stephen. "Dryland river adjustments in a warming world". Geography 106, n.º 1 (2 de enero de 2021): 49–52. http://dx.doi.org/10.1080/00167487.2020.1862592.

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12

Costa, A. C., A. Bronstert y J. C. de Araújo. "A channel transmission losses model for different dryland rivers". Hydrology and Earth System Sciences Discussions 8, n.º 5 (4 de octubre de 2011): 8903–62. http://dx.doi.org/10.5194/hessd-8-8903-2011.

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Abstract. Channel transmission losses in drylands take place normally in extensive alluvial channels or streambeds underlain by fractured rocks. They can play an important role in flood prediction, groundwater recharge, freshwater supply and channel-associated ecosystems. We aim to develop a semi-distributed channel transmission losses model, a coupling of formulations which are more suitable for data-scarce dryland environments, applicable for both hydraulically disconnected losing streams and hydraulically connected losing(/gaining) streams. Hence, this approach should be able to cover a large variation in climate and hydro-geologic controls, which are typically found in dryland regions of the world. Traditionally, channel transmission losses models have been developed for site specific conditions. Our model was firstly evaluated for a losing/gaining, hydraulically connected 30 km reach of the Jaguaribe River, Ceará, Brazil, which controls a catchment area of 20 000 km2. Secondly, we applied it to a small losing, hydraulically disconnected 1.5 km channel reach in the Walnut Gulch Experimental Watershed (WGEW), Arizona, USA. The model based on the perceptual hydrological models of the reaches was able to predict reliably the stream flow for the both case studies. For the larger river reach, the evaluation of the hypotheses on the dominant hydrological processes was fundamental for reducing structural model uncertainties and improving the stream flow prediction, showing that both lateral stream-aquifer water fluxes and groundwater flow in the underlying alluvium parallel to the river course are necessary to predict stream flow and channel transmission losses, the former process being more relevant than the latter. The sensitivity analysis showed that even if the parameters can "potentially" produce large flow exchanges between model units in the saturated part of the modelling, large flow exchanges do not happen because they are restricted by the actual hydraulic gradient between the model units. Moreover, the saturated-part-based parameters (active in the larger river) produced much smaller variation in the sensitivity coefficient than those (active in the smaller river) which drive the unsaturated part of the channel transmission losses model.

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13

Bao, Wen. "Drought Prevention and Mitigation of Agricultural Development in the Dry Upper Valley of Minjiang River". Applied Mechanics and Materials 195-196 (agosto de 2012): 1243–48. http://dx.doi.org/10.4028/www.scientific.net/amm.195-196.1243.

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The distinct characteristics in the dry upper valley of Minjiang River were the complication of natural environment, the frangibility of ecosystem, dryland farming systems, and the transition of culture. Drought is a many faceted natural disaster that leads to serious socio-economic impacts particularly affecting agricultural production of the dry valley. The basic objective of drought prevention and mitigation is to minimize possible adverse outcomes within the constraints of the costs involved. The paper elaborates the specific vulnerability contexts and situation of dryland mountain agricultural systems, highlights the importance of stabilizing dryland agriculture by evolving contingent crop production strategies, economies diversify to include agro-industry or various tertiary products, agricultural extension etc. in dry valley area of upper Minjiang River.

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14

McGregor, Glenn B., Jonathan C. Marshall y Martin C. Thoms. "Spatial and temporal variation in algal-assemblage structure in isolated dryland river waterholes, Cooper Creek and Warrego River, Australia". Marine and Freshwater Research 57, n.º 4 (2006): 453. http://dx.doi.org/10.1071/mf05128.

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The scale at which algal biodiversity is partitioned across the landscape, and the biophysical processes and biotic interactions which shape these communities in dryland river refugia was studied on two occasions from 30 sites in two Australian dryland rivers. Despite the waterholes studied having characteristically high levels of abiogenic turbidity, a total of 186 planktonic microalgae, 253 benthic diatom and 62 macroalgal species were recorded. The phytoplankton communities were dominated by flagellated cryptophytes, euglenophytes and chlorophytes, the diatom communities by cosmopolitan taxa known to tolerate wide environmental conditions, and the macroalgal communities by filamentous cyanobacteria. All algal communities showed significant differences between catchments and sampling times, with a suite of between 5 and 12 taxa responsible for ~50% of the observed change. In general, algal assemblage patterns were poorly correlated with the measured environmental variables. Phytoplankton and diatom assemblage patterns were weakly correlated with several waterhole geomorphic measures, whereas macroalgal assemblage patterns showed some association with variability in ionic concentration.

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15

Sheldon, Fran, Stuart E. Bunn, Jane M. Hughes, Angela H. Arthington, Stephen R. Balcombe y Christine S. Fellows. "Ecological roles and threats to aquatic refugia in arid landscapes: dryland river waterholes". Marine and Freshwater Research 61, n.º 8 (2010): 885. http://dx.doi.org/10.1071/mf09239.

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Dryland rivers are renowned for their periods of ‘boom’ related to the episodic floods that extend over vast floodplains and fuel incredible production, and periods of ‘bust’ where the extensive channel network is restricted to the permanent refugial waterholes. Many of these river systems are unregulated by dams but are under increasing pressure, especially from water abstraction and overland flow interception for agriculture and mining. Although some aquatic organisms with desiccation-resistant life stages can utilise ephemeral floodplain habitats, the larger river waterholes represent the only permanent aquatic habitat during extended periods of low or no flow. These waterholes act as aquatic refugia in an otherwise terrestrial landscape. Variable patterns of connection and disconnection in space and time are a fundamental driver of diversity and function in these dryland river systems, and are vital for dispersal and the maintenance of diverse populations, generate the spatial and temporal variability in assemblage structure for a range of different organisms and fuel the productivity that sustains higher trophic levels. Changes to natural patterns of connection and disconnection of refugial waterholes, owing to water-resource development or climate change, will threaten their persistence and diminish their functional capacity to act as aquatic refugia.

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16

Stromberg, J. C., P. B. Shafroth y A. F. Hazelton. "Legacies of flood reduction on a Dryland river". River Research and Applications 28, n.º 2 (15 de septiembre de 2010): 143–59. http://dx.doi.org/10.1002/rra.1449.

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17

Robertson, Alistar I., Adrienne Burns y Terry J. Hillman. "Scale-dependent lateral exchanges of organic carbon in a dryland river during a high-flow experiment". Marine and Freshwater Research 67, n.º 9 (2016): 1293. http://dx.doi.org/10.1071/mf15371.

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We estimated the magnitude and direction of exchanges of particulate organic carbon (POC) and dissolved organic carbon (DOC) between the river and four floodplain wetlands (billabongs) and a 140-km reach of riverbank and floodplain of the Murrumbidgee River during a managed high-flow experiment. There was a net transport of organic carbon from the river to billabongs during connection, ranging from 87 to 525kg POC per billabong or from 1.4 to 5.7g POC m–2 of billabong sediment surface area and from 36 to 4357kg DOC, or from 0.4 to 29.8g DOC m–2. At the whole-reach scale, there was a net loss of 754Mg POC from the river channel to riverbank and floodplain and a net input of 821Mg DOC to the river channel. This DOC input, which was small relative to the total organic carbon in transit, was likely to have contributed significantly to oxidative processes in the river. The DOC entering the river was derived from litter and soils in riverbank habitats or from abraded biofilms in the river channel. The results support an extended flood-pulse concept that includes in-channel flow pulses as important elements in the biogeochemistry of dryland rivers. Piggybacking dam releases on tributary flows to deliver in-channel flows delivers significant benefit for riverine organic-matter cycles.

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18

Leigh, Catherine, Fran Sheldon, Richard T. Kingsford y Angela H. Arthington. "Sequential floods drive 'booms' and wetland persistence in dryland rivers: a synthesis". Marine and Freshwater Research 61, n.º 8 (2010): 896. http://dx.doi.org/10.1071/mf10106.

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Flow is a key driver regulating processes and diversity in river systems across a range of temporal and spatial scales. In dryland rivers, variability in the timing and scale of floods has specific ecological significance, playing a major role in sustaining biotic diversity across the river-floodplain mosaic. However, longitudinal effects of floods are equally important, delivering water downstream through channels and wetland complexes. Interaction among spatially distributed wetlands, their connecting channel and floodplain geomorphology and the temporally variable flow events not only creates the spatial complexity in dryland rivers but also determines temporal persistence of wetlands. These act as hydrological ‘sponges’, absorbing water from upstream and needing to fill before releasing water downstream. Sequential high flow events are essential for the ecological persistence of riverine wetlands and the transmission of flows further downstream through the channel network. These flood sequences maintain aquatic refugia and drive booms in productivity sustaining aquatic and terrestrial biota over large spatial and temporal scales. Disrupting the sequence, with modified flow regimes and water removal for diversion (e.g. irrigation), significantly reduces the opportunity for wetland replenishment. As a result, the benefits of sequential flooding to the wetland ‘sponges’ and their biotic communities will be lost.

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19

Goss, Kevin F. "Environmental flows, river salinity and biodiversity conservation: managing trade-offs in the Murray - Darling basin". Australian Journal of Botany 51, n.º 6 (2003): 619. http://dx.doi.org/10.1071/bt03003.

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The Murray–Darling basin's river system suffers from over-allocation of water resources to consumptive use and salinity threats to water quality. This paper draws attention to the current state of knowledge and the need for further investigations into the biological effect of river salinity on aquatic biota and ecosystems, the threats of dryland salinity to terrestrial biodiversity, and managing environmental flows and salinity control to limit the trade-offs in water-resource security and river salinity.There is growing evidence that river salt concentrations lower than the normally adopted threshold have sublethal effects on species and ecosystems, over a longer time period. Further knowledge is required.There is no agreed process for incorporating terrestrial biodiversity values at risk into a strategic response for dryland-salinity management. This is a public policy issue to be addressed.Recent studies have quantified the trade-off in surface water flow and river salinity from refforestation and revegetation of upland catchments to control salinity. The potential losses or benefits to environmental values have not been quantified.Such improved knowledge is important to the Murray–Darling basin and relevant to other river basins and catchments in Australia.

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20

East, Jessica L., Christopher Wilcut y Allison A. Pease. "Aquatic food-web structure along a salinized dryland river". Freshwater Biology 62, n.º 4 (20 de enero de 2017): 681–94. http://dx.doi.org/10.1111/fwb.12893.

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21

Reynolds, L. V., P. B. Shafroth y P. K. House. "ABANDONED FLOODPLAIN PLANT COMMUNITIES ALONG A REGULATED DRYLAND RIVER". River Research and Applications 30, n.º 9 (24 de septiembre de 2013): 1084–98. http://dx.doi.org/10.1002/rra.2708.

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22

McDonald, Alyson K., Zhuping Sheng, Charles R. Hart y Bradford P. Wilcox. "Studies of a regulated dryland river: surface-groundwater interactions". Hydrological Processes 27, n.º 12 (12 de mayo de 2012): 1819–28. http://dx.doi.org/10.1002/hyp.9340.

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23

Paisei, Valentin, Soetjipto Moeljono y Rima H. S. Siburian. "Kondisi Biofisik Serta Gangguan Terhadap Hutan Pada Areal Buffer Zone Bantaran Sungai Apo Distrik Jayapura Utara". Cassowary 4, n.º 1 (30 de enero de 2021): 19–27. http://dx.doi.org/10.30862/casssowary.cs.v5.i1.91.

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APO river has a length of 3 kilometers with a width of 7 meters and flows from headwaters in the village Angkasa Pura to empty into the sea which is administered into the village administration area Bhayangkara. The purpose of this study to (1) identify the biophysical conditions in the area of the buffer zone of the river sepantaran Apo. (2) Identifying the form of land use in the bufferzone area of the Apo River from downstream to upstream. (3) Provide management recommendations in the form of land suitability directions to carry out Forest and Land Rehabilitation activities in the bufferzone area of the Apo river. Descriptive method with map interpretation and consists of several stages that include the preparation stage, the stage of processing and preliminary processing of data, field checking stage, the stage of data analysis, and recommendations on the implementation of Forest and Land Rehabilitation activities in the area of the river BufferZone Apo. Biophysical conditions of the area BufferZone river Apo has the characteristics of land cover types that include dry forest primary dry forest secondary, dryland farming mixed with shrubs, bushes, settlements, soil types litosol, with altitude ranging from 0 m asl - 690m above sea level . BufferZone slope in the area of very varied ranging from flat to very steep.In accordance with the decline in the quality of primary dryland forest to secondary dryland forest covering 22.04 hectares in 2009-2018 and activities that resulted in the removal of 44.80 hectares of secondary forest in 2000-2009, the large changes in the nature of both deforestation and degradation of from 2000 to 2018 thus covering an area of 66.84 hectares or 18.94% of the total research area, namely the Apo river bufferzone. Most of the areas that are categorized as quite suitable are forest areas that are experiencing deforestation and degradation and the recommended land is suitable enough to carry out RHL activities in the bufferzone area of the Apo River, only covering an area of 91.05 hectares or 25.80% of the bufferzone area. Apo river.

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24

Ielpi, Alessandro y Mathieu G. A. Lapôtre. "Linking sediment flux to river migration in arid landscapes through mass balance". Journal of Sedimentary Research 92, n.º 8 (22 de agosto de 2022): 695–703. http://dx.doi.org/10.2110/jsr.2022.118.

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ABSTRACT Lateral migration is a key process shaping sinuous rivers and controlling sediment exchange with floodplains. The rate at which channels migrate is affected by bend curvature, bank erodibility, and sediment supply. The relationship between migration rate and sediment supply is poorly understood in dryland regions, where direct measurements are scarce. Here we propose a simple mass-balance model to estimate the sediment flux of ephemeral streams in North America's Great Basin and establish a comparison with timelapse photogrammetric data of lateral migration. The model takes into consideration variables such as long-term hillslope erosion, transient sediment storage in intra-catchment lowlands, and sediment bypass to depocenters. Our results point to first-order similarities in how sediment supply drives channel migration across diverse hydro-climatic regimes. However, we find that, for a given sediment supply and channel width, and despite their ephemeral discharge, dryland streams with minimal bank vegetation migrate about three times faster than humid-climate, vegetated ones. This difference in migration pace likely results from the compound effect of bank erodibility and bend geometry. Our model sheds new light on the driving mechanisms of channel mobility in dryland streams and may find application in assessing the sediment budgets of ungauged streams, reservoir trapping, and morphodynamic adjustments in stressed watersheds.

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25

Mueller, E. N., A. Güntner, T. Francke y G. Mamede. "Modelling sediment export, retention and reservoir sedimentation in drylands with the WASA-SED model". Geoscientific Model Development 3, n.º 1 (8 de abril de 2010): 275–91. http://dx.doi.org/10.5194/gmd-3-275-2010.

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Abstract. Current soil erosion and reservoir sedimentation modelling at the meso-scale is still faced with intrinsic problems with regard to open scaling questions, data demand, computational efficiency and deficient implementations of retention and re-mobilisation processes for the river and reservoir networks. To overcome some limitations of current modelling approaches, the semi-process-based, spatially semi-distributed modelling framework WASA-SED (Vers. 1) was developed for water and sediment transport in large dryland catchments. The WASA-SED model simulates the runoff and erosion processes at the hillslope scale, the transport and retention processes of suspended and bedload fluxes in the river reaches and the retention and remobilisation processes of sediments in reservoirs. The modelling tool enables the evaluation of management options both for sustainable land-use change scenarios to reduce erosion in the headwater catchments as well as adequate reservoir management options to lessen sedimentation in large reservoirs and reservoir networks. The model concept, its spatial discretisation scheme and the numerical components of the hillslope, river and reservoir processes are described and a model application for the meso-scale dryland catchment Isábena in the Spanish Pre-Pyrenees (445 km2) is presented to demonstrate the capabilities, strengths and limits of the model framework. The example application showed that the model was able to reproduce runoff and sediment transport dynamics of highly erodible headwater badlands, the transient storage of sediments in the dryland river system, the bed elevation changes of the 93 hm3 Barasona reservoir due to sedimentation as well as the life expectancy of the reservoir under different management options.

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26

Reid, Michael A., Martin C. Thoms, Stephen Chilcott y Kathryn Fitzsimmons. "Sedimentation in dryland river waterholes: a threat to aquatic refugia?" Marine and Freshwater Research 68, n.º 4 (2017): 668. http://dx.doi.org/10.1071/mf15451.

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In dryland river systems subject to prolonged low and no flow periods, waterholes, or sections of river channel that are deep relative to the rest of the channel and that retain water for longer periods of no flow, provide refugia for aquatic biota and hence are critical to the resilience of aquatic ecosystems. This study examined physical, chemical and bio-stratigraphy in refugial waterholes situated along four distributaries of the Lower Balonne River system in semi-arid Australia. In doing so we reconstructed environmental histories for the waterholes, calculated how sedimentation rates have changed in response to land use change over the past two centuries, and assessed whether they are threatened by increased sedimentation through potential effects on waterhole depth and hence persistence times and habitat quality. Our study found that sedimentation rates have increased substantially since European settlement, most likely in response to removal of groundcover by grazers. The increased sediment accumulation rates are estimated to have reduced persistence times during low and no flow periods of the waterholes by 2–4 months. Despite evidence from other similar systems in Australia that increased influx of sediment coincided with loss of submerged macrophytes, stratigraphic records of preserved pollen and diatoms did not provide consistent evidence of biotic or habitat quality changes within the waterholes associated with European settlement.

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27

Dean, D. J. y D. J. Topping. "Geomorphic change and biogeomorphic feedbacks in a dryland river: The Little Colorado River, Arizona, USA". GSA Bulletin 131, n.º 11-12 (24 de abril de 2019): 1920–42. http://dx.doi.org/10.1130/b35047.1.

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Abstract The Little Colorado River in Arizona, United States, has undergone substantial geomorphic change since the late 1800s and early 1900s, consisting of sediment accumulation following an earlier period of likely widespread sediment evacuation. We analyzed hydrologic and geomorphic data at different spatial and temporal scales to determine the primary mechanisms responsible for these changes, and to provide context for periods of sediment evacuation and accumulation in other rivers. Peak-flow magnitude has progressively declined since the 1920s despite the occurrence of four alternating periods of high and low total annual flow. Largely coincident with this hydrologic change, the channel has narrowed between 72% and 88% in some reaches since the 1930s, with increases in sinuosity in wide alluvial valleys causing ∼21%–32% reductions in channel slope. Dense stands of vegetation colonized, and thus stabilized, the newly deposited floodplains. Although large, long-duration floods caused some channel widening, these floods have been too infrequent to offset the progressive narrowing. Channel narrowing, increases in sinuosity, decreases in slope, and increases in vegetative roughness appear to have caused biogeomorphic feedbacks, thereby exacerbating sediment deposition, disrupting flood conveyance, and contributing to decreases in peak-flow magnitude and in sediment transport. The progressive increase in water development in parts of the basin has also likely contributed to progressive declines in peak flow. These results show that biogeomorphic feedback processes combined with human water development may be as important as, if not more important than, changes in climate in driving hydrologic, geomorphic, and sediment-load change in dryland river environments.

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28

Burford, M. A., A. T. Revill, D. W. Palmer, L. Clementson, B. J. Robson y I. T. Webster. "River regulation alters drivers of primary productivity along a tropical river-estuary system". Marine and Freshwater Research 62, n.º 2 (2011): 141. http://dx.doi.org/10.1071/mf10224.

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Worldwide, rivers continue to be dammed to supply water for humans. The resulting regulation of downstream flow impacts on biogeochemical and physical processes, potentially affecting river and estuarine productivity. Our study tested the hypothesis that primary production in the downstream freshwater reaches of a dammed river was less limited by light and nutrients relative to downstream estuarine primary production. In a tropical dryland Australian river estuary, we found that water-column primary productivity was highest at freshwater sites that had lowest light attenuation. Nitrogen may also have limited primary productivity. Below the freshwater zone was a region of macrotidal mixing with high concentrations of suspended soil particles, nutrients and chlorophyll a, and lower but variable primary productivity rates. Light controlled productivity, but the algal cells may also have been osmotically stressed due to increasing salinity. Further downstream in the estuary, primary productivity was lower than the freshwater reaches and light and nutrient availability appear to be a factor. Therefore the reduced magnitude of peak-flow events due to flow regulation, and the resulting decrease in nutrient export, is likely to be negatively impacting estuarine primary production. This has implications for future development of dams where rivers have highly seasonal flow.

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29

Miyazono, Seiji, Reynaldo Patiño y Christopher M. Taylor. "Desertification, salinization, and biotic homogenization in a dryland river ecosystem". Science of The Total Environment 511 (abril de 2015): 444–53. http://dx.doi.org/10.1016/j.scitotenv.2014.12.079.

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30

Li, Jiaguang, Charlie S. Bristow, Stefan M. Luthi y Marinus E. Donselaar. "Dryland anabranching river morphodynamics: Río Capilla, Salar de Uyuni, Bolivia". Geomorphology 250 (diciembre de 2015): 282–97. http://dx.doi.org/10.1016/j.geomorph.2015.09.011.

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31

Gibson, J. J., M. A. Sadek, D. J. M. Stone, C. Hughes, S. Hankin, D. I. Cendón y S. E. Hollins. "Stable isotope tracing of water exchange along a dryland river". Geochimica et Cosmochimica Acta 70, n.º 18 (agosto de 2006): A201. http://dx.doi.org/10.1016/j.gca.2006.06.406.

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32

Stromberg, Juliet C., Elizabeth Makings, Amy Eyden, Robert Madera, John Samsky, Francis S. Coburn y Brenton D. Scott. "Provincial and cosmopolitan: floristic composition of a dryland urban river". Urban Ecosystems 19, n.º 1 (18 de junio de 2015): 429–53. http://dx.doi.org/10.1007/s11252-015-0482-4.

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33

Callow, J. N. "POTENTIAL FOR VEGETATION-BASED RIVER MANAGEMENT IN DRYLAND, SALINE CATCHMENTS". River Research and Applications 28, n.º 8 (15 de abril de 2011): 1072–92. http://dx.doi.org/10.1002/rra.1506.

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34

Beyer, Patricia J. "Variability in channel form in a free-flowing dryland river". River Research and Applications 22, n.º 2 (2006): 203–17. http://dx.doi.org/10.1002/rra.906.

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35

Costelloe, J. F., J. R. W. Reid, J. C. Pritchard, J. T. Puckridge, V. E. Bailey y P. J. Hudson. "Are alien fish disadvantaged by extremely variable flow regimes in arid-zone rivers?" Marine and Freshwater Research 61, n.º 8 (2010): 857. http://dx.doi.org/10.1071/mf09090.

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The proliferation of alien fish in dryland rivers potentially obstructs the maintenance of river health. Modified flow regimes are hypothesised to facilitate invasions by alien fish but in unregulated dryland rivers, large floods provide a recruitment advantage for native over alien species whereas droughts favour alien species. We tested these hypotheses by using data from a 3-year study (2000–2003) of fish populations in the unmodified rivers of the Lake Eyre Basin (LEB) of Australia. Results from a lower reach of Cooper Creek were compared with those of an earlier study (1986–1992). During both periods, large floods occurred, with return periods ranging from >1 in 5 to >1 in 25 years. In the lower Cooper, decreases in the abundance of alien species relative to native species, and dramatic increases in recruitment of native species, were observed during a 1–3-year period following large floods. In two other rivers in 2000–2003, there was no statistically significant change in the already low abundances of alien species. We suggest that the naturally variable hydrological regimes and native-dominant fish assemblages of the unregulated LEB rivers afford some resistance to the establishment and proliferation of alien fish through flood and drought conditions.

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36

Morón, Sara, Kathryn Amos y Sandra Mann. "Fluvial reservoirs in dryland endorheic basins: the Lake Eyre Basin as a world-class modern analogue". APPEA Journal 54, n.º 1 (2014): 119. http://dx.doi.org/10.1071/aj13014.

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Intracratonic dryland basins have been common throughout geological time and significant hydrocarbon reservoirs are contained in these basins. Based on a literature compilation of fluvial dryland reservoirs, the authors demonstrate the need for new modern analogue data from dryland fluvial systems, and present new field data from the Neales River, in the Lake Eyre catchment. The selected study reach has a complex planform, with a downstream transition from single channel to anabranching. Results of the observations of the channel bed grain size, the geomorphology and the channel geometry (width and depth) allow the authors to infer that the channel bed grain size is more strongly related to planform geomorphology than the channel geometry (width to depth ratios). Based on the grain size and channel geometry data the authors present, the authors conclude that the planform geomorphology exerts a greater control on channel bed material size than channel geometry. This interpretation is based on the analysis of satellite imagery, topographic survey data and grain size descriptions. In this paper, the authors provide channel geometry data and grain size data that will improve understanding of dryland fluvial sedimentology. The authors hope this contributes to enhancing hydrocarbon exploration and production in petroleum reservoirs developed in dryland fluvial settings.

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37

Higgisson, William, Linda Broadhurst, Foyez Shams, Bernd Gruber y Fiona Dyer. "Reproductive Strategies and Population Genetic Structure in Two Dryland River Floodplain Plants, Marsilea drummondii and Eleocharis acuta". Genes 13, n.º 9 (23 de agosto de 2022): 1506. http://dx.doi.org/10.3390/genes13091506.

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Aquatic plants share a range of convergent reproductive strategies, such as the ability to reproduce both sexually and asexually through vegetative growth. In dryland river systems, floodplain inundation is infrequent and irregular, and wetlands consist of discrete and unstable habitat patches. In these systems, life history strategies such as long-distance dispersal, seed longevity, self-fertilisation, and reproduction from vegetative propagules are important strategies that allow plants to persist. Using two aquatic plants, Marsilea drummondii and Eleocharis acuta, we investigated the proportions of sexual and asexual reproduction and self-fertilisation by employing next-generation sequencing approaches, and we used this information to understand the population genetic structure of a large inland floodplain in western New South Wales (NSW), Australia. Asexual vegetative reproduction and self-fertilisation were more common in M. drummondii, but both species used sexual reproduction as the main mode of reproduction. This resulted in a highly differentiated genetic structure between wetlands and a similar genetic structure within wetlands. The similarity in genetic structure was influenced by the wetland in the two species, highlighting the influence of the floodplain landscape and hydrology on structuring population genetic structure. The high levels of genetic variation among wetlands and the low variation within wetlands suggests that dispersal and pollination occur within close proximity and that gene flow is restricted. This suggests a reliance on locally sourced (persistent) seed, rather than asexual (clonal) reproduction or recolonisation via dispersal, for the population maintenance of plants in dryland rivers. This highlights the importance of floodplain inundation to promote seed germination, establishment, and reproduction in dryland regions.

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38

Amos, Kathryn, Carley Goodwin y Angel Soria. "Incised valleys in marginal-lacustrine depositional environments: a new reservoir analogue from Lake Eyre, central Australia". APPEA Journal 52, n.º 1 (2012): 513. http://dx.doi.org/10.1071/aj11040.

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Incised-valley fill deposits can form important hydrocarbon reservoirs and provide pathways for hydrocarbon migration. Incised-valleys formed in marginal-marine environments are well described, however, marginal-lacustrine incised-valleys have been the focus of extremely few investigations and are poorly understood. This paper provides a new description of incised-fluvial systems that are presently constructing terminal deposits in embayments around the shoreline of Lake Eyre, central Australia. It is anticipated that better awareness of such deposits will assist in the recognition of these depositional environments in the rock record, which should be useful for exploration purposes and for the generation of improved models for continental dryland fluvial-lacustrine reservoir deposits. A classification of all significant river mouth deposits around Lake Eyre (width >300 m; n = 104), from topographic map and satellite image data, found that 54% are incised-valleys presently accreting a terminal deposit in a shoreline embayment (playa lake estuary). The depositional elements of three incised-valley systems have been mapped using satellite imagery in a GIS platform, from which element geometries are described. Controls on incised-valley formation are investigated by comparing these observations with evidence for past lake highstands and neotectonics and observations from satellite images, geological map data, and digital elevation model data. The terminal splay deposits of rivers around Lake Eyre are well-used analogues for dryland reservoirs; however, the focus has been on deposits accreting directly onto the playa. It is likely the incised-valleys and terminal deposits in the embayments described here will be of interest to companies exploring in, and producing from, ancient drylands and other lacustrine depositional environments.

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39

Biggs, A. J. W. y P. Mottram. "Links between dryland salinity, mosquito vectors, and Ross River Virus disease in southern inland Queensland—an example and potential implications". Soil Research 46, n.º 1 (2008): 62. http://dx.doi.org/10.1071/sr07053.

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The impacts of dryland salinity on landscapes and agriculture are well documented, but few links have been made to public health. A cluster of cases of Ross River Virus (RRV) disease in the vicinity of a dryland salinity expression in the town of Warwick, Queensland, has highlighted the potential role of secondary salinity expressions as breeding zones for mosquitoes, including vector species of RRV. It is suggested that further work is required to investigate the matter in Queensland, particularly in relation to the expansion of urban populations in south-east Queensland into old agricultural lands containing secondary salinity expressions.

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40

Sheldon, Fran y Christine S. Fellows. "Water quality in two Australian dryland rivers: spatial and temporal variability and the role of flow". Marine and Freshwater Research 61, n.º 8 (2010): 864. http://dx.doi.org/10.1071/mf09289.

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Water quality, along with hydrology, plays an important role in the spatial and temporal dynamics of a range of ecological patterns and processes in large rivers and is also often a key component of river health assessments. Geology and land use are significant drivers of water quality during flow periods while during periods of no-flow, local-scale factors such as evaporation, groundwater influence and the concentration and precipitation of compounds are important. This study explored the water quality changes in two Australian dryland rivers, the Cooper Creek (Lake Eyre Basin) and the Warrego River (Murray–Darling Basin), across different hydrological phases over several years. Water quality varied both spatially and temporally; the greatest spatial variability occurred during the no-flow phase, with temporal changes driven by flow. Concentrations of major anions and cations also varied spatially and temporally, with an overall cation dominance of calcium and magnesium and an anion dominance of bicarbonate. This bicarbonate dominance contrasts with previous data from inland lentic systems where sodium chloride was found to dominate. Such extreme spatial and temporal variability hampers successful derivation of water quality guidelines for these variable rivers and suggests such guidelines would need to be developed with respect to ‘flow phase’.

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41

Chiew, FHS y TA Mcmahon. "Groundwater recharge from rainfall and irrigation in the campaspe river basin". Soil Research 29, n.º 5 (1991): 651. http://dx.doi.org/10.1071/sr9910651.

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Reliable estimates of groundwater recharge are required for effective evaluation of management options for salinity control and high water-tables in the Riverine Plain of south-eastern Australia. This paper provides a brief description of the integrated surface and groundwater modelling approach used to estimate regional recharge rates and presents the recharge rates estimated for the Campaspe River Basin. The integrated model is a powerful management tool as it can predict the relationship between rainfall, irrigation, recharge and rises in the water-table levels. The model predicted that approximately 15% of irrigation water recharges the shallow aquifer. Approximately 6% of rainfall contributes to recharge in the irrigated areas while 4 to 5% of rainfall becomes recharge in the dryland areas. Rainfall makes a greater contribution in the irrigation areas compared to the dryland areas because irrigation predisposes the soil to recharge from rainfall. The water-table levels in the irrigation areas are currently rising at approximately 0.14 m yr-1. This rate of rise will increase faster than the increase in irrigation applications.

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42

Puckridge, J. T., F. Sheldon, K. F. Walker y A. J. Boulton. "Flow variability and the ecology of large rivers". Marine and Freshwater Research 49, n.º 1 (1998): 55. http://dx.doi.org/10.1071/mf94161.

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Ecological processes in large rivers are controlled by their flow variability. However, it is difficult to find measures of hydrological variability that characterize groups of rivers and can also be used to generate hypotheses about their ecology. Multivariate analyses of the hydrographs of 52 rivers worldwide revealed distinctive patterns of flow variability that were often correlated with climate. For example, there were groups of rivers that corresponded broadly with ‘tropical’ and ‘dryland’ climates. However, some rivers from continental climates occupy both extremes of this range, illustrating the limitations of simple classification. Individual rivers and groups of rivers may also have different hydrographic ‘signatures’, and attempts to combine measures of hydrological variability into indices mask biologically significant information. This paper identifies 11 relatively independent measures of hydrological variability that help categorize river types and are each associated with aspects of fish biology. Ways are suggested by which the Flood Pulse Concept can be expanded to encompass hydrological variability and accommodate differences among groups of rivers from different climatic regions. Such recognition of the complex role of hydrological variability enhances the value of the concept for river conservation, management and restoration.

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43

Lang, S. C., T. H. D. Payenberg, M. R. W. Reilly, T. Hicks, J. Benson y J. Kassan. "MODERN ANALOGUES FOR DRYLAND SANDY FLUVIAL-LACUSTRINE DELTAS AND TERMINAL SPLAY RESERVOIRS". APPEA Journal 44, n.º 1 (2004): 329. http://dx.doi.org/10.1071/aj03012.

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Ephemeral sandy fluvial-lacustrine deltas and terminal splays associated with dryland depositional environments are important reservoirs in many basins around the world, in both pericratonic and intracratonic settings (Triassic of Algeria; Triassic of the North Sea; and Pliocene of the Caspian Sea). Research on modern depositional analogues from dryland basins offers insights into these types of reservoirs. Australia’s modern Lake Eyre Basin, an arid to hyper-arid, low-accommodation intracratonic basin in central Australia, provides an ideal natural laboratory.This paper highlights field observations of modern, sand-prone, reservoir analogues from the Neales River and Umbum Creek, on the western fringe of Lake Eyre, including unique aerial observations of sedimentation from a rare flood event in an ephemeral fluvial system. These rivers flow irregularly in a dryland setting, but are prone to flash flooding and highly variable discharge that moves large volumes of sediment over a few hours or days. Although there are variations in sediment type and discharge, similarities exist with the key reservoir elements common to most modern and ancient dryland fluvial-lacustrine systems.Distinctive elements include fluvial point bar and associated overbank deposits, distributive avulsion channels and down-dip terminal splays, either on the floodplain or onto the playa lake fringe. The terminal splays are formed, where there is not a pre-existing standing body of water, during rapidly decelerating flows with high-flow regime, transitional to low-flow regime conditions. Typical structures include parallel lamination, convex-upward parallel lamination, climbing ripples and small-scale 2D and 3D dunes. Flow interference with in-channel and floodplain vegetation is an important sediment-trapping mechanism with reservoir quality implications. Aeolian deflation is also significant as it causes the removal of fine-grained sediments during dry periods. The main controls on sediment preservation include the overall low-accommodation setting and rare major lake-filling events controlled by flooding out-of-phase with flows down the western rivers. Depositional products are either high-net-to gross fluvial- terminal splay sheet sands or lower net-to-gross fluvial- terminal splay-lacustrine delta sand sheets or stringers.

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44

Jenkins, K. M., A. J. Boulton y B. Gawne. "Colonisation pathways of microinvertebrates following flooding in a dryland Australian river". SIL Proceedings, 1922-2010 28, n.º 3 (octubre de 2002): 1444–47. http://dx.doi.org/10.1080/03680770.2001.11902694.

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45

Abubakar, Ibrahim Tukur, A. Yusuf Maharazu, Ajayi Olofin Emmanuel y Abdulhamid Adnan. "Shallow groundwater condition for irrigation along dryland river basin, northwestern Nigeria". Journal of Dryland Agriculture 4, n.º 1 (31 de diciembre de 2018): 1–11. http://dx.doi.org/10.5897/joda2018.0003.

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46

Thoms, Martin y Michael Delong. "Ecosystem Responses to Water Resource Developments in a Large Dryland River". Water Resources Research 54, n.º 9 (septiembre de 2018): 6643–55. http://dx.doi.org/10.1029/2018wr022956.

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47

Thoms, M. C. y F. Sheldon. "Water resource development and hydrological change in a large dryland river: the Barwon–Darling River, Australia". Journal of Hydrology 228, n.º 1-2 (febrero de 2000): 10–21. http://dx.doi.org/10.1016/s0022-1694(99)00191-2.

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48

Bowman, DMJS y L. Mcdonough. "Feral Pig (Sus Scrofa) Rooting in a Monsoon Forest-Wetland Transition, Northern Australia." Wildlife Research 18, n.º 6 (1991): 761. http://dx.doi.org/10.1071/wr9910761.

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A grid of 447 cells (each 50x50 m) was set up in a wet monsoon rain forest on a gradual slope above the Adelaide River floodplain in the Australian Northern Territory. Surveys of pig (Sus scrofa) rooting were carried out at approximately 3-month intervals from November 1988 to September 1989. The pigs had only limited effects on the forest in both the wet and dry seasons. The seasonally flooded swamp communities (Melaleuca forest and sedgeland) were primarily exploited in the dry season; dryland communities ([Eucalyptus] and Lophostemon forests) were exploited during the wet season. Rainfall during the previous wet season may have influenced the pattern of rooting in the dryland forests. Rooting and ground cover were weakly positively related in 3 out of the 4 surveys.

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49

Farias, Rafaela Lima de, Cristina Stenert, Leonardo Maltchik y Elvio Sergio Figueredo Medeiros. "Partitioning of macroinvertebrate assemblages across temporary pools in an intermittent dryland river". Inland Waters 10, n.º 4 (4 de junio de 2020): 480–92. http://dx.doi.org/10.1080/20442041.2020.1738841.

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50

Bagstad, K. J., S. J. Lite y J. C. Stromberg. "VEGETATION, SOILS, AND HYDROGEOMORPHOLOGY OF RIPARIAN PATCH TYPES OF A DRYLAND RIVER". Western North American Naturalist 66, n.º 1 (enero de 2006): 23–44. http://dx.doi.org/10.3398/1527-0904(2006)66[23:vsahor]2.0.co;2.

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