Academic literature on the topic 'Upland river valley ecosystems'

River valley bottoms have hydrological, geomorphological, and ecological importance and are buffers for protecting the river from upland nutrient loading coming from agriculture and other sources. They are relatively flat, low-lying areas of the terrain that are adjacent to the river and bound by increasing slopes at the transition to the uplands. These areas have under natural conditions, a groundwater table close to the soil surface. The objective of this paper is to present a stepwise GIS approach for the delineation of river valley bottom within drainage basins and use it to perform a national delineation. We developed a tool that applies a concept called cost distance accumulation with spatial data inputs consisting a river network and slope derived from a digital elevation model. We then used wetlands adjacent to rivers as a guide finding the river valley bottom boundary from the cost distance accumulation. We present results from our tool for the whole country of Denmark carrying out a validation within three selected areas. The results reveal that the tool visually performs well and delineates both confined and unconfined river valleys within the same drainage basin. We use the most common forms of wetlands (meadow and marsh) in Denmark’s river valleys known as Groundwater Dependent Ecosystems (GDE) to validate our river valley bottom delineated areas. Our delineation picks about half to two-thirds of these GDE. However, we expected this since farmers have reclaimed Denmark’s low-lying areas during the last 200 years before the first map of GDE was created. Our tool can be used as a management tool, since it can delineate an area that has been the focus of management actions to protect waterways from upland nutrient pollution.

Inland valleys are defined as the upper reaches of river systems. These include valley bottoms and minor floodplains,their hydromorphic fringes and upland slopes and crests. These occupy 22-52 million ha of land in W. Africa and although of good agricultural potential are only marginally used. An agro-ecological characterization developed in the Cte d'Ivoire, is outlined on 4 levels: macro (1:1 000 000-1:5 000 000), reconnaissance (1:100 000-1:250 000), semi-detailed (1:25 000-1:50 000) and detailed (1:5000-10 000). Methods of characterization at each of these levels are discussed and examples of actual application given plus the mechanisms applied in disaggregation (scaling down) and aggregation (scaling up) between levels. This approach allows: (1) a systematic description of different inland valley agro-ecosystems; (2) identification of constraints to agricultural use; (3) targeting and implemention of research; and (4) extrapolation of research results and transfer of new technology to similar areas. Studies carried out show variation in (bio)physical and land use factors is considerable. The set of descriptors now developed allows for: (1) extrapolation of the relation between biophysical driving factors and actual land use; (2) identification of geographical areas where improved management is promising; and (3) indications on the type of improvements required.

We tested the hypothesis that upland wetland restorations provide the same quality of wetland, in terms of ecosystem services and biodiversity, as natural wetlands in the St. Lawrence River Valley. Water quality (pH, alkalinity, colored dissolved organic matter, phytoplankton community composition, chlorophyll-a, fecal coliform, total phosphorus, dissolved nitrate, turbidity, specific conductivity) in 17 natural and 45 restored wetlands was compared to determine whether wetland restoration provided similar physicochemical conditions as natural wetlands in the Saint Lawrence River Valley of northeastern New York State. Natural wetlands were more acidic, which was hypothesized to result from the avoidance of naturally acidic regions by farmers seeking to drain wetlands for crop and pasture use. Natural wetlands had significantly greater fecal coliform concentrations. Restored wetlands had significantly greater specific conductivity and related ions, and this is attributed to the creation of wetlands upon marine clay deposits. Other water quality indicators did not differ between restored and natural wetlands. These findings confirm other research at these same wetlands showing no substantial differences between restored and natural wetlands in major biotic indicators. Thus, we conclude that wetland restoration does result in wetlands that are functionally the same as the natural wetlands they were designed to replicate.

Permafrost thermal conditions across the Qinghai–Tibet Engineering Corridor (QTEC) is of growing interest due to infrastructure development. Most modeling of the permafrost thermal regime has been conducted at coarser spatial resolution, which is not suitable for engineering construction in a warming climate. Here we model the spatial permafrost thermal dynamics across the QTEC from the 2010 to the 2060 using the ground thermal model. Soil properties are defined based on field measurements and ecosystem types. The climate forcing datasets are synthesized from MODIS-LST products and the reanalysis product of near-surface air temperature. The climate projections are based on long-term observations of air temperature across the QTEC. The comparison of model results to field measurements demonstrates a satisfactory agreement for the purpose of permafrost thermal modeling. The results indicate a discontinuous permafrost distribution in the QTEC. Mean annual ground temperatures (MAGT) are lowest (<−2.0 °C) for the high mountains. In most upland plains, MAGTs range from −2.0 °C to 0 °C. For high mountains, the average active-layer thickness (ALT) is less than 2.0 m, while the river valley features ALT of more than 4.0 m. For upland plains, the modeled ALTs generally range from 3.0 m to 4.0 m. The simulated results for the future 50 years suggest that 12.0%~20.2% of the permafrost region will be involved in degradation, with an MAGT increase of 0.4 °C~2.3 °C, and the ALT increasing by 0.4 m~7.3 m. The results of this study are useful for the infrastructure development, although there are still several improvements in detailed forcing datasets and a locally realistic model.

River valleys of Volhynian Upland are characterized by a larger number of terraces and a greater depth of their downcutting compared with neighbouring Polissia and Male Polissia. We established that the major rivers of Volhynian Upland have floodplain and mostly three terraces. The valley of the Horyn River is different from others by presence of fourth terrace. According to received information, the age of forming of the highest terrace (revealed only in the Horyn Valley) can be considered as Early Pleistocene, the third terrace – Middle Pleistocene, and the two lowest terraces – Late Pleistocene. Relief of the Early and Middle Pleistocene terraces is characterized by high degree of dissection and presence of sufficiently thick loess cover. At higher Late Pleistocene terrace loess cover isn’t revealed everywhere and has a small thickness (typically up to 5 m). The lowest terrace in most valleys has local distribution and it is composed mainly of sandy material. The surface of this terrace is located on several hypsometric levels. Floodplain usually has two high-rise levels. It formed in the Holocene. Key words: river valley, terrace, floodplain, Volhynian Upland, Horyn River, Styr River, Zakhidnyi Buh River.

The Smoking Hills Upland and lower Horton River valley, on the Arctic coast of Canada 300 km east of the Mackenzie Delta, retain an extended record of subaerial erosion of nearly flat-lying Cretaceous shales. This erosion led to the development of (i) a very gently sloping low-relief upland surface (Early Pleistocene(?)), (ii) a slightly steeper intermediate surface, and (iii) younger steep valley walls, terraces, and broad valley bottoms. No direct glacial contribution to any of these landforms can be recognized. An early interglacial(?) fluvial episode is recorded in plateau-cap sediments. Suggestions of an early (mid-Pleistocene or earlier) glaciation overwhelming the Smoking Hills Upland are found in (i) anomalies in drainage patterns, (ii) disturbances in bedding, believed to have been caused by ice thrusting, and (iii) local occurrences of diamictons. Later, probably Early Wisconsinan, glaciation left meltwater channels in peripheral areas. The Late Wisconsinan ice sheet did not reach the Smoking Hills Upland but may have had an indirect influence by modyfying discharge and sediment transport of Horton River.

Abstract Analyses of water conditions in the Lower Basin of the Biebrza River and deposit stratigraphy were conducted in cross-sections through the valley, where geodetic measurements were also made. Peat type in particular layers of the soil profile was determined in selected cross-sections at 100 m intervals. The Lower Basin of the Biebrza River is diverse with regard to the type of water supply to a peatbog, the shape of the bio-accumulative basin’s bottom and the slope of peatbog surface along and across the valley. These factors resulted in the development of different habitats in the peatbog. Northern part of the Lower Basin, between the main road in the village Osowiec and the inflows of the Kosódka and Wissa rivers to the Biebrza River, is a narrow valley supplied mainly with overflowing water of the Biebrza River. Habitats and hydrogenic deposits of this area developed in relation to the type and layout of mineral substratum and to the duration and depth of seasonal flooding. North-west part is mainly supplied by ground water from the adjacent upland. Peat layers, developed on ground waters flowing out from the upland, markedly slope toward the bed of the Biebrza River. Considerable fluctuations of the ground water level can be observed there and most frequently the sites are periodically drying. Part of the valley, from the inflows of the Kosódka and Wissa rivers down to the Biebrza and Narew River confluence, is mainly supplied with underground waters from upland.

Using public materials (articles, open-file reports of geological survey at the Severnye Uvaly, and digital elevation models), we studied river valleys of the Severnye Uvaly Upland and established specific types of gold placer-like occurrences and interconnection between river valley structure and placer location. We distinguished 4 cycles of erosion in Late Cenozoic at the Severnye Uvaly. For placer forming, the one of the most important features is a spatial coincidence of valleys in every cycle of erosion. An analysis of the longitudinal and transverse profiles of the valleys according to the DSM allows evaluating the content of the gold and its location in the river valley.

Hymenochaete carpatica has been found in 1994 in Czętochowa Upland, "Parkowre" nature reserve, in Wiercica river valley situated on calcareous area, 290-310 m above see level, on fissured bark of Acer pseudoplatanus. This contribution corresponds to the paper by Chlebicki (2003) who has recently discovered scveral localities of H. carpatica in Sudetes and Carpathians. Both papers present a set of sites of H. carpatica reported hitherto from Poland, and contribute to the knowledge on its distribution in Europe.

Healthy riparian vegetation has a positive impact on the adjacent river. Unfortunately, riparian vegetation is often threatened by human impacts such as dam construction and clearing. To gain the knowledge underlying the effects of such impacts and to aid riparian rehabilitation, the objective of this thesis was: to determine riparian vegetation association with, and response to, variation in fluvial geomorphology over several scales and consequently to fluvial disturbance. Only woody riparian plant species were considered. Flood disturbance was the unifying theme of this thesis. Linked to this theme and arising from the main objective was the supposition that plant interactions with the abiotic environment, but not biotic interactions between species, control riparian species distribution because of frequent fluvial disturbances. Woody riparian vegetation and riverine environmental variables were recorded along the upper Murrumbidgee River at three spatial scales based on a geomorphic hierarchy for Chapter 2. Multivariate analysis was used to group species and to associate environmental variables with vegetation at the three spatial scales. Observations at the two larger scales, of river segment (site) and riparian reach (transect), identified a river-longitudinal speciescomposition gradient associated with geology, river width and stream channel slope. Observations at the smallest scale of geomorphic units (plot) identified a lateral riparian gradient and also the longitudinal gradient; these gradients were associated with geomorphic variation, land use, plot elevation and also river longitudinal variables. Using the same data set, but varying the spatial scale of analysis caused the species composition pattern to change between scales. Increase in scale of observation, that is from geomorphic unit to reach and segment scales, resulted in disproportionate importance of rarer species and decreased importance of some key riparian species at the larger scales. It would appear that in this instance the geomorphic unit scale best described patches of different species composition because this scale had high spatial resolution and was also able to identify multiple gradients of environmental variation. It was recommended that riparian sampling take place at scales that represent dominant gradients in the riparian zone. These gradients are represented by geomorphic scales, indicating the appropriateness of using geomorphic based scales for observation of riparian vegetation. Chapter 3 considered whether there is a geomorphic template upon which riparian vegetation is patterned and whether it is associated with process variables, such as flooding and soil type. This question was investigated at different spatial scales in three ways: i) by an experiment to determine whether soil nutrient condition affects plant growth; ii) by graphical analysis of trends between geomorphic units, species and process variables; and iii) by analysis of vegetation distribution data. The smallest scale (meso) found experimental differences in plant growth because of soil type. Plants growing in sand had the lowest performance, with an average plant Relative Growth Rate (RGR) of 0.01, compared to plants growing in soils with small amounts of silt or clay particles, with an average plant RGR of 0.04. This pattern was attributed to differences in nutrients. Clear relationships were demonstrated at the larger geomorphic unit scale between species distribution and process variables. For example, hydrology and substratum type were found to be associated with geomorphic units and species. The largest scale considered in Chapter 3 was the riparian reach scale. At this scale species were clearly grouped around reach type. Therefore, geomorphology was considered to be a template for riparian species distribution. Findings in this chapter suggested that geomorphic variables should be good predictors of riparian species distribution. This hypothesis was tested and supported in Chapter 6. The experiments reported in Chapter 4 aimed to determine whether inundation depth and duration affected plant performance and survival for five common riparian zone species. Riparian seedling patterns in the field were also compared with experimental results to test whether species performance was reflected by field distribution. The experiments that were conducted included an inundation period and depth experiment, and a survival period test whilst under complete inundation. Biomass and height relative growth rates were determined, and the results were analysed using factorial Analysis of Variance. Obligate riparian species (Callistemon sieberi, Casuarina Cunninghamiana, Leptospermum obovatum) were found to be tolerant of inundation duration and depth, to the point where inundation provided a growth subsidy. On the other hand, non-obligate riparian species (Acacia dealbata, Kunzea ericoides) were either just tolerant of inundation or showed a negative growth response. For instance, C. sieberi demonstrated an average height RGR of 0.04 after complete inundation and 0.007 when not inundated, while A. dealbata had an average height RGR of 0.001 after complete inundation and 0.01 when not inundated. These experimental findings were found to closely reflect both seedling and adult plant distribution in the field such that inundation tolerant species were found close to the river and intolerant species further away. Thus, the conclusion was drawn that riparian species establishment and distribution is affected by inundation and that change to the flood regime could have serious impacts on riparian zone plant composition. The other aim of this chapter was to determine whether optimum germination temperatures were associated with flood or rainfall. Growth chamber germination trials were conducted at air temperatures of 15�C, 20�C and 25�C to determine the 'best' germination temperature. These germination patterns at different temperatures were then related to annual variation in field temperature, flooding period and rainfall. No evidence was found to suggest a relationship between ideal germination temperature and flood season, rather it was suggested that germination was patchy through time and may simply reflect recent rainfall. Investigations that were reported in Chapter 5 aimed to elucidate relationships between species and flow velocity variables. Two experiments were conducted: i) a flume experiment to determine the effect of flow velocity on plant growth; and ii) an experiment to observe the response of plants to damage (imitating flood damage) and inundation. Field observations of species distribution and flow velocity related variables were also conducted to put the flume results into a real-world context. Treatments for the flume experiment were fast flow velocity (0.74 m s-1), slow velocity (0.22 m s-1) and no velocity (control) but still inundated. All treatments were flooded completely for four days. Subsequent biomass and height relative growth rates were determined, and the results were analysed using factorial Analysis of Variance. Results were unexpected, given that obligate species exposed to the fastest velocity had the highest growth rate with an average height RGR of 0.046, compared to plants in still water, which grew the least with an average height RGR of 0.013. It was hypothesised that this response was because relatively greater carbon dioxide and oxygen levels were available in the moving water compared to the still water. With regard to shoot damage, the species that were nonobligate riparian species lost more leaves from velocity treatment than the obligate riparian species. The cut and flood experiment found growth of the obligate species (Casuarina cunninghamiana) to be greater after cutting than the non-obligate species. Flooding was not found to have an effect in the cut and flood experiment, probably because the period to sampling after flood treatment was longer (4 weeks) than other flooding experiments (3 weeks). Field observations were found to support the experimental findings, with a gradient of species across the riparian zone that reflected potential flood velocities. Therefore, velocity is one of a suite of riparian hydrological factors that are partially responsible for the gradient of species across the riparian zone. Potentially the absence of flooding could result in a homogeneous mix of species, rather than a gradient, except on the very edge of the river. The study that was reported in Chapter 6 investigated a technique for predicting riparian vegetation distribution. One of the aims of this investigation was to address a current riparian rehabilitation shortfall, which was how to objectively select species to plant for rehabilitation. Field data were collected from three confined river valleys in south-eastern New South Wales. Using data on plant species occurrence and site and plot measures of soils, hydrology and climate, an AUSRIVAS-style statistical model, based on cluster and discriminant analysis, was developed to predict the probability of species occurrence. The prediction accuracy was 85 % when tested with a separate set of plots not used in model construction. Problems were encountered with the prediction of rarer species, but if the probability of selection was varied according to the frequency of species occurrence then rarer species would be predicted more often. Various models were tested for accuracy including three rivers combined at the geomorphic unit (plot) scale and riparian reach (transect) scale in addition to a Murrumbidgee River plot scale model. Surprisingly, the predictive accuracy of the all rivers and single river models were approximately the same. However, the difference between the large scale and small scale models pointed to the importance of including small scale flood-related parameters to predict riparian vegetation. When these riparian predictions were compared to predictive outcomes from a hill slope model, which was assumed to be affected by fewer disturbances (i.e. flooding), predictive accuracies were not very different. Overall though, predictive accuracy for riparian vegetation was high, but not good enough to support the supposition that riparian vegetation is abiotically controlled because of frequent flood disturbance. Nevertheless, geomorphology and consequently flood effects are still important for the determination of the riparian community composition. Overall, riparian vegetation was found to be closely linked to its environment (evidenced in Chapters 2, 3, 4, 5) in a predictable manner (Chapter 6). Species pattern relied on flood disturbance affecting species distribution. Some riparian species were found to be highly tolerant of flooding and gained a growth advantage after flooding (Chapters 4 and 5). Therefore, flood tolerance was important for the formation of a species gradient across the riparian zone. These species tolerances and growth requirements reflect riparian geomorphic pattern (Chapter 3), which was suggested to form a template on which riparian vegetation is structured.

Degraded rangelands and riparian woodlands in eastern North Dakota are increasing in frequency. Two studies were conducted to address reduced forage quantity and quality and reduced regeneration of riparian tree and shrub species. Research objectives were to (1) analyze multiple pre-seeding treatments to determine impacts on rangeland production of interseeded native species; and (2) determine if fencing, weed-barrier fabric, mowing, or herbicide treatments can increase survivability of riparian tree and shrub seedling plantings. Pre-seeding treatments with herbicide showed significantly higher production of native species than the control. High-fencing/mowing treatment and high-fencing/weed-barrier fabric/herbicide treatment in riparian tree and shrub plantings resulted in significantly higher survival than the control. These findings will be used to develop future research and management strategies.
Robert H. Levis II Cross Ranch Fellowship
Gladys Allen Trust of St. Louis
Red River Regional Council
North Dakota Department of Health
Environmental Protection Agency (EPA)

River terraces form prominent features of the valley floor morphology of many upland valleys in Scotland. Little is known, however, about valley floor landform development in many of these valleys. Previous studies have generally explained the terraces as the outwash products of meltwaters from the most recent cold periods. Detailed investigation of a major valley in the Scottish Highlands challenges, for at least one site, this well established concept and proposes the occurrence of at least three phases of Holocene terrace development. The correlation of terrace surfaces has traditionally been based upon the construction of height-range diagrams. An alternative approach to terrace correlation and dating is developed in this study using data from Glen Feshie, south-west Cairngorms. Terrace fragments are numerically classified and objectively grouped using quantitative soil-stratigraphic data. Principal Components Analysis and a hierarchical clustering technique numerically define five soil-stratigraphic units and place these on a relative time scale. Various methods of absolute dating control permit association of these units with five phases of terrace development. These are placed at 13,000, 10,000, 3,600, 1,000, 80, radiocarbon years BP. Comparison of palaeochannel networks preserved on the terrace surfaces suggests that these phases of terrace development have been associated with changes in channel pattern morphology. A unified approach to analysis of channel pattern morphology is developed and from this a new technique for palaeohydrological interpretation of gravel-bed streams. A segment density index is developed which allows total sinuosity to be predicted from just a part of the braided channel network. Application of these techniques to the Glen Feshie terraces demonstrates a trend for an overall decrease in discharge from the oldest terrace surfaces to the present day. Assessment of these landform changes within the context of known environmental fluctuations in the Cairngorms suggests that the early-mid Holocene was a period of relative landscape stability while the late Holocene was characterised by increasing instability. These changes may have been associated with the changes in river behaviour. However, spatial variation in the depth of the fill/bedrock interface may produce a discontinuous river response to changing environmental conditions.

Os recursos hídricos são considerados bem comum e, por isso, devem ser geridos de forma integrada; garantindo, assim, aproveitamento otimizado com mínimo de conflitos. O objetivo deste trabalho foi estudar o comportamento de variáveis limnológicas na microbacia do rio Jacupiranguinha (município de Cajati – SP, Baixo Ribeira de Iguape), em quatro períodos hidrológicos distintos, com base nas teorias ecológicas de ecossistemas fluviais. As coletas foram realizadas em janeiro (verão), abril (outono), julho (inverno) e setembro (primavera) em onze pontos, no eixo longitudinal do rio Jacupiranguinha, com alguns abrangendo locais após lançamentos de efluentes de indústrias e esgoto doméstico, um ponto no rio Guaraú e um ponto no rio Jacupiranga. Levando-se em conta a sazonalidade a maior precipitação ocorreu em janeiro (305 mm), como era esperado, seguida pelas de setembro (266 mm), julho (119 mm) e abril (115 mm). Vazão e velocidade de escoamento tiveram relação direta com a precipitação e a vazão aumentou de montante à jusante, devido à contribuição de efluentes. A devastação da mata ciliar ocasionou incidência uniforme de radiação solar em todo o eixo longitudinal do rio Jacupiranguinha, além de facilitar a entrada de sólidos suspensos para o rio, principalmente no período chuvoso. Este rio recebe efluentes domésticos e de uma indústria de fertilizantes, que gera uma descontinuidade de fluxo de seus nutrientes da cabeceira à foz. Altos valores de condutividade, e dos compostos de fósforo a partir da entrada do efluente da indústria de fertilizantes indicam que ele muda as características do rio nos pontos à jusante deste e, por isso, é possível dividir o eixo longitudinal do rio Jacupiranguinha em duas regiões. A análise do sedimento revelou maiores concentrações de nitrogênio total no mês de setembro, provavelmente devido à entrada de carga alóctone ocasionada pelas chuvas e maiores concentrações de fósforo total foram obtidas no período seco. A comunidade bentônica apresentou variação temporal, provavelmente, devido a fatores hidráulicos, como vazão e velocidade de escoamento. O aumento da riqueza e diversidade no período de chuvas, provavelmente ocorreram em função do revolvimento do substrato que, neste período era composto por partículas mais finas. A baixa riqueza e diversidade de espécies encontradas no rio Jacupiranguinha nos demais períodos indica comprometimento da qualidade da água neste sistema
Water resources are a well good, so they should be managed in an integrated form, guaranteeing their optimized use, with less conflict. The aim of this work was to study the behavior of limnological variables in the Jacupiranguinha river micro basin (Cajati city, São Paulo, Low Ribeira de Iguape Valley) in four different hydrological periods based on the conceptual structures of stream ecosystems. Samples were colleted in January (summer), April (autumn), July (winter) and September (spring) in 11 points throughout the river, in points with discharge of sewage and industrial effluents, 1 point on Jacupiranga river and 1 on Guaraú river. Considering seasonality the higher precipitation occurred on January (305 mm), like it was expected, followed by that on September (266 mm), July (119 mm) and April (115 mm). Drainage speed and discharge were positively related with precipitation and there were an increase from headwaters to mouth in discharge because of the entrance of effluents. The absence of the riparian vegetation caused uniform incidence of solar radiation throughout the entire river channel; besides, it had facilitated the entrance of suspended solids (allochthonous input) during rainy season. The fertilizing industry, located in Cajati city, causes a discontinuity flow of nutrients in the river. High conductivity values and phosphorus compounds from the industry effluents change the continuum of the river and allow its section in two regions: before and after the industry effluent entrance. The sediment analysis revealed higher nitrogen concentrations on September, probably because the allochthonous input occasioned by the rain and higher phosphorous concentration was found on dry season. The benthic community presented temporal variation probably due to hydraulic factors as discharge and speed drainage. The increase of richness and diversity on rainy season is due to the suspension of organic matter cumulated on sediment. The low species richness and diversity in the other seasons on Jacupiranguinha river indicate that the water quality is not so good

Prior to European settlement, native prairie dominated the landscape of the Willamette Valley. Today, due to urbanization, agriculture, and the cessation of burning, only isolated remnants of these grasslands still exist. In response to conservation concerns, there has been a move to restore the remaining prairies in the Willamette Valley, and prescribed burning and sowing native seed are often top candidates for grassland restoration. However, the effects of burning on native seedling establishment and the spread of weedy exotics are largely unknown. In this study, I investigated how prescribed burning affects native and exotic species seedling establishment on three upland prairie vegetation types in the Willamette Valley. The general approach was to sow a known number of seeds from several native and exotic grassland species into experimentally manipulated plots, designed to separate the effects of litter removal from the other effects of burning, and to monitor seedling densities. Germinability and dormancy characteristics of the sowed seeds were also addressed. An additional study focused on the fire temperatures at soil surface in three grassland vegetation types and two burn sizes. Burning increased the establishment of most or all of the sown native species in the two low quality, exotic grass sites. Exotic seedling establishment also tended to increase, but did not differ significantly from unburned plots for most species tested. On the higher quality, native bunchgrass site, burning did not significantly improve native species establishment, but did significantly increase the establishment of short-lived exotic species over those in unburned plots. The germination and dormancy characteristics of the native and exotic species tested indicate that grasses, both native and exotic, are more likely than forbs to be non-dormant in the autumn following dispersal. Forbs, especially native forbs tend to require cold-stratification for maximum germinability. During grassland fire, temperatures at soil surface were relatively cool. Fire temperature intensity was highest in the higher quality native bunchgrass vegetation. These burns reached higher temperatures significantly closer to the soil surface than the plot burns in lower quality sites dominated by annual or perennial exotic grasses. Average temperatures in a two hectare broadcast burn and in replicated 2m x 2.5m plot bums in an annual exotic grassland were very similar. Prescribed burning can be an excellent tool for the restoration of low-quality upland prairies when combined with sowing native seeds in the fall. However, on high-quality prairie, prescribed burning may be a poor restoration choice for promoting native seedlings, as burning promoted weedy species without enhancing native seedling establishment.
Graduation date: 1997

Identifying mechanisms that determine who lives and dies is the first step in developing successful restoration techniques for rare species and endangered habitats. We studied interactions that affect establishment of native plant forbs of conservation concern at the seedling stage to support the theoretical basis for restoration activities in Pacific Northwest prairies. Specifically, we tested the hypothesis that seedling establishment is controlled by 1) competition with or 2) facilitation by existing vegetation and that the interaction is mediated in part by environmental stress. We direct-seeded or planted vegetative plugs of Lupinus oreganus, Castilleja levisecta, Erigeron decumbens, Iris tenax and Sidalcea malviflora ssp. virgata into 20 plots with a range of community compositions in high-stress upland prairies at each of three sites. We counted seedlings and estimated cover of plant functional groups as well as litter, bare soil and disturbance then used linear regression to test for effects of these factors on seedling establishment. We found evidence of indirect facilitation of grass on seedling establishment in the first year: higher accumulations of leaf litter increased seedling numbers at two sites. In the second year, there was evidence of facilitation by live vegetation and litter on seedlings at one site, but no net effect of either competition or facilitation at the other two sites. Overall, we found more evidence for positive interactions than we did for competition. In particular, litter appeared to have a positive effect on seedling establishment of L. oreganus and S. malviflora ssp. virgata. This is contrary to the common perception that litter inhibits plant establishment but supports the theory that facilitation is more common in high stress sites; practitioners should consider seeding into leaf litter at some sites. To support a robust approach to conservation and reintroduction of species with dormant seed, we characterized dormancy types and developed germination protocols for S. malviflora ssp. virgata and I. tenax. S. malviflora ssp. virgata has physical dormancy and may have physiological dormancy. Scarification followed by four weeks of cold moist stratification was effective in initiating germination. I. tenax has morphophysiological dormancy which is overcome by four weeks of warm moist stratification followed by 6-12 weeks of cold stratification. We also conducted a meta-analysis of experiments that tested pre-sowing seed scarification of L. oreganus and conclude that breaking physical dormancy prior to direct seeding does not support higher establishment relative to unscarified seeds in this species.
Graduation date: 2012

<em>Abstract.</em>—We evaluated several approaches for measuring natural and anthropogenic habitat characteristics to predict benthic macroinvertebrate assemblages over a range of urban intensity at 85 stream sites in the Santa Clara Valley, California. Land cover was summarized as percentage urban land cover and impervious area within upstream buffers and the upstream subwatersheds. Field measurements characterized water chemistry, channel slope, sediment, and riparian canopy. In addition to applying the visual-based habitat assessment in U.S. Environmental Protection Agency’s rapid bioassessment protocol, we developed a simplified urban habitat assessment index based on turbidity, fine sediment deposition, riparian condition, and channel modification. Natural and anthropogenic habitat variables covaried along longitudinal stream gradients and were highly correlated with elevation. At the scale of the entire watershed, benthic macroinvertebrate measures were equally correlated with variables expressing natural gradients and urbanization effects. When natural gradients were reduced by partitioning sites into ecoregion subsection groupings, habitat variables most highly correlated with macroinvertebrate measures differed between upland and valley floor site groups. Among the valley floor sites, channel slope and physical modification of channel and riparian habitats appeared more important than upstream land cover or water quality in determining macroinvertebrate richness and ordination scores. Among upland sites, effects of upstream reservoir releases on habitat quality appeared important. Rapid habitat evaluation methods appeared to be an effective method for describing habitat features important to benthic macroinvertebrates when adapted for the region and the disturbance of interest.

This paper explores the possibility of cursus monuments being located in upland locations in Britain. These rectangular enclosures date to the Early Neolithic, and are almost all known as cropmark sites in lowland river valley contexts. However, Loveday explores various examples where upland upstanding features such as field banks could have prehistoric origins and easily be misinterpreted. Evidence from three case-study areas in Scotland – Upper Strathearn and Strathtay, Nithsdale, and the Biggar Area – is covered in detail to suggest a context for, and likely location of, possible upland cursus monuments. This is then placed with an upland British context, and the chapter concludes with news of a recent discovery that vindicates the approach of the author.

<em>Abstract.</em>—The lower American River, located in Sacramento County, California, provides important habitat, a high-quality water source, a critical floodway, and a spectacular regional recreational parkway. It is also a key water source for the Central Valley Project, which provides irrigation water to 3 million acres of the country’s most productive agricultural lands. The river supports 43 species of native and nonnative fish, including fall-run Chinook salmon <em>Oncorhynchus tshawytscha </em>and steelhead <em>O. mykiss</em>. In the last decade, one quarter of all fall-run Chinook salmon produced in California’s Central Valley have come from the American River. The Sacramento region’s population is expected to double to more than 2 million people in the next 30 years. Water demand to meet population growth will cause additional stress on a river system that currently experiences low flow and high temperatures during critical salmonid spawning and rearing life stages. Increased demand for American River water outside the region will contribute to higher fall river water temperatures and more frequent fluctuating flows that result in stranding and/or isolation of fish. In 1993, regional stakeholders decided that new methods were needed to avoid water shortages, environmental degradation, groundwater contamination, and limits to economic prosperity. Consequently, they created the Water Forum. After 6 years of intense, interest-based negotiations, 40 stakeholder organizations approved the comprehensive Water Forum Agreement in 2000. The agreement allows the region to meet its needs in a balanced way through implementation of a comprehensive package of linked actions.

<em>Abstract.</em>—In less than two centuries, the lower Boise River below Lucky Peak Dam in southwestern Idaho has been transformed from a meandering, braided, gravel-bed river that supported large runs of salmon to a channelized, regulated, urban river that also provides irrigation water to more than 1,300 km2 of land. The construction of three large dams in the upper basin dramatically altered the flow regime and sediment supply to the lower river. Flows are no longer sufficient to mobilize bed sediments and have allowed cottonwood trees and alien hardwoods to stabilize parafluvial surfaces, thereby narrowing sections of the river channel. Cadastral survey notes of 1867 and 1868 were used to recreate features associated with the lower Boise River Valley and identify characteristics of the river channel prior to dam construction and urbanization. Gravel and sand bars, historically present throughout the river, which are necessary to maintain biodiversity and productivity, are currently scarce. Sloughs were a dominant feature on the floodplain of the late 1800s, but today have been converted to irrigation canals, drains, or residential and commercial land uses. Flow alterations, water quality degradation, and habitat loss due to urbanization near the lower Boise River have resulted in macroinvertebrate and fish assemblages dominated by tolerant and alien species.

The nine chapters in Part II build on the physical, biological, and theoretical frameworks set out in Part I, but with a focus on process regimes and change in specific environments. With its emphasis on much larger spatial scales, Part I showed how the Mediterranean basin is a product of long-term interactions between all components of the Earth system. It showed how these interactions drive landscape and ecosystem processes and environmental change. The chapters in Part II examine Mediterranean-wide patterns too, but explore process interactions in sharper resolution and across scales ranging from individual soil profiles, hillslopes, and habitats to larger landscape elements including lake basins, river valleys, dune systems, and coastal plains. Much of the region is dominated by mountains and many process interactions are especially vivid in the Mediterranean because of the erosive energy available in steep and active tectonic settings, and the presence of soft rocks vulnerable to mass movements and water erosion. Abrupt transitions from uplands to lowlands— and the differential response to tectonic uplift of hard and soft rock terrains—are notable features. The seasonally dry climate can leave bare slopes exposed to high intensity rains, and river sediment yields are typically much higher than in adjacent regions. It can be argued that the Quaternary records of these interactions are more varied and better preserved than in any other part of the world. Recent major advances include the development of high resolution proxy climate data from speleothems and robust dating frameworks for fluvial, glacial, and palaeoecological records. These records have provided important new insights into the tempo of climate, landscape, and ecosystem change in the Mediterranean region and beyond. A variety of sedimentary archives also provide insights into the changing nature and intensity of human action in the Mediterranean landscape during the course of the Pleistocene and Holocene and this is a core theme of Part II. The region is unique because of the very early and widespread impact of humans in landscape and ecosystem change—and the richness of the archaeological and geological archives in which it is chronicled.

<em>Abstract.</em>—We assessed the structure of periphyton, benthic macroinvertebrate, and fish assemblages and their associations with environmental variables at 17 sites on streams of the highly urbanized Santa Ana River basin in Southern California. All assemblages exhibited strong differences between highly urbanized sites in the valley and the least-impacted sites at the transition between the valley and undeveloped mountains. Results within the urbanized area differed among taxa. Periphyton assemblages were dominated by diatoms (>75% of total taxa). Periphyton assemblages within the urbanized area were not associated with any of the measured environmental variables, suggesting that structure of urban periphyton assemblages might be highly dependent on colonization dynamics. The number of Ephemeroptera, Trichoptera, and Plecoptera (EPT) taxa included in macroinvertebrate assemblages ranged from 0 to 6 at urbanized sites. Benthic macroinvertebrate assemblages had significant correlations with several environmental variables within the urban area, suggesting that stream size and permanence were important determinants of distribution among the species able to survive conditions in urban streams. Only 4 of 16 fish species collected were native to the drainage. Fish assemblages of urbanized sites included two native species, arroyo chub <em>Gila orcuttii </em>and Santa Ana sucker <em>Catostomus santaanae, </em>at sites that were intermediate in coefficient of variation of bank-full width, depth, bed substrate, and water temperature. Alien species dominated urbanized sites with lesser or greater values for these variables. These results suggest that urban streams can be structured to enhance populations of native fishes. Continued study of urban streams in the Santa Ana River basin and elsewhere will contribute to the basic understanding of ecological principles and help preserve the maximum ecological value of streams in highly urbanized areas.

This chapter presents a case study of the Israeli National Biodiversity Monitoring Program (IBM) that encompasses a diverse set of ecosystems. Israel is located at a crossroads of Africa, Asia, and Europe. It sits at the southeastern tip of the Mediterranean ecosystem, bordering the vast Saharo-Arabian desert belt to its south and connected via the Rift Valley to the heights of Southeast Asia and the dry tropical ecosystems of East Africa. This combination of geography and ecology provides habitats for a remarkably high number of species, but the high densities of Israel's population and its rapid development, intensive land use, and climatic change threaten this biodiversity. A key component of a strategy to conserve biodiversity is a monitoring program that can identify the current state and trends—stable, declining, or thriving—of biodiversity in a country. The case study discusses the goals and implementation of the IBM, with particular attention to the challenges of replication and repeatability in this long-term monitoring program.

Highly imperiled Oregon white oak ecosystems are a regional conservation priority of numerous organizations, including Oregon Metro, a regional government serving over one million people in the Portland area. Previously dominant systems in the Pacific Northwest, upland prairie and oak woodlands are now experiencing significant threat, with only 2% remaining in the Willamette Valley in small fragments (Hulse et al. 2002). These fragments are of high conservation value because of the rich biodiversity they support, including rare and endemic species, such as Delphinium leucophaeum (Oregon Department of Agriculture, 2020). Since 2010, Metro scientists and volunteers have collected phenology data on approximately 140 species of forbs and graminoids in regional oak prairie and woodlands. Phenology is the study of life-stage events in plants and animals, such as budbreak and senescence in flowering plants, and widely acknowledged as a sensitive indicator of environmental change (Parmesan 2007). Indeed, shifts in plant phenology have been observed over the last few decades as a result of climate change (Parmesan 2006). In oak systems, these changes have profound implications for plant community composition and diversity, as well as trophic interactions and general ecosystem function (Willis 2008). While the original intent of Metro’s phenology data-collection was to track long-term phenology trends, limitations in data collection methods have made such analysis difficult. Rather, these data are currently used to inform seasonal management decisions on Metro properties, such as when to collect seed for propagation and when to spray herbicide to control invasive species. Metro is now interested in fine-tuning their data-collection methods to better capture long-term phenology trends to guide future conservation strategies. Addressing the regional and global conservation issues of our time will require unprecedented collaboration. Phenology data collected on Metro properties is not only an important asset for Metro’s conservation plan, but holds potential to support broader research on a larger scale. As a leader in urban conservation, Metro is poised to make a meaningful scientific contribution by sharing phenology data with regional and national organizations. Data-sharing will benefit the common goal of conservation and create avenues for collaboration with other scientists and conservation practitioners (Rosemartin 2013). In order to support Metro’s ongoing conservation efforts in Oregon white oak systems, I have implemented a three-part master’s project. Part one of the project examines Metro’s previously collected phenology data, providing descriptive statistics and assessing the strengths and weaknesses of the methods by which the data were collected. Part two makes recommendations for improving future phenology data-collection methods, and includes recommendations for datasharing with regional and national organizations. Part three is a collection of scientific vouchers documenting key plant species in varying phases of phenology for Metro’s teaching herbarium. The purpose of these vouchers is to provide a visual tool for Metro staff and volunteers who rely on plant identification to carry out aspects of their job in plant conservation. Each component of this project addresses specific aspects of Metro’s conservation program, from day-to-day management concerns to long-term scientific inquiry.

The Greater Yellowstone Area (GYA) is one of the last remaining large and nearly intact temperate ecosystems on Earth (Reese 1984; NPSa undated). GYA was originally defined in the 1970s as the Greater Yellowstone Ecosystem, which encompassed the minimum range of the grizzly bear (Schullery 1992). The boundary was enlarged through time and now includes about 22 million acres (8.9 million ha) in northwestern Wyoming, south central Montana, and eastern Idaho. Two national parks, five national forests, three wildlife refuges, 20 counties, and state and private lands lie within the GYA boundary. GYA also includes the Wind River Indian Reservation, but the region is the historical home to several Tribal Nations. Federal lands managed by the US Forest Service, the National Park Service, the Bureau of Land Management, and the US Fish and Wildlife Service amount to about 64% (15.5 million acres [6.27 million ha] or 24,200 square miles [62,700 km2]) of the land within the GYA. The federal lands and their associated wildlife, geologic wonders, and recreational opportunities are considered the GYA’s most valuable economic asset. GYA, and especially the national parks, have long been a place for important scientific discoveries, an inspiration for creativity, and an important national and international stage for fundamental discussions about the interactions of humans and nature (e.g., Keiter and Boyce 1991; Pritchard 1999; Schullery 2004; Quammen 2016). Yellowstone National Park, established in 1872 as the world’s first national park, is the heart of the GYA. Grand Teton National Park, created in 1929 and expanded to its present size in 1950, is located south of Yellowstone National Park1 and is dominated by the rugged Teton Range rising from the valley of Jackson Hole. The Gallatin-Custer, Shoshone, Bridger-Teton, Caribou-Targhee, and Beaverhead-Deerlodge national forests encircle the two national parks and include the highest mountain ranges in the region. The National Elk Refuge, Red Rock Lakes National Wildlife Refuge, and Grays Lake National Wildlife Refuge also lie within GYA.