WorldWideScience

Sample records for channelisation riparian structure

  1. Effects of Channelisation, Riparian Structure and Catchment Area on Physical Habitats in Small Lowland Streams

    DEFF Research Database (Denmark)

    Pedersen, Morten Lauge

    2009-01-01

    Rivers and streams form a longitudinal network in which physical conditions and biological processes change through the river system. Geomorphology, topography, geology and hydraulic conditions change from site to site within the river system, thereby creating a complex network of reaches that are......, substrata and coverage of macrophytes. Riparian land use, valley form and information on channelisation and channel dredging were also collected. Small headwater streams were either dominated by forests or semi-natural land use. In contrast, the riparian areas of the streams in the larger streams were...

  2. Riparian vegetation structure under desertification scenarios

    Science.gov (United States)

    Rosário Fernandes, M.; Segurado, Pedro; Jauch, Eduardo; Ferreira, M. Teresa

    2015-04-01

    Riparian areas are responsible for many ecological and ecosystems services, including the filtering function, that are considered crucial to the preservation of water quality and social benefits. The main goal of this study is to quantify and understand the riparian variability under desertification scenario(s) and identify the optimal riparian indicators for water scarcity and droughts (WS&D), henceforth improving river basin management. This study was performed in the Iberian Tâmega basin, using riparian woody patches, mapped by visual interpretation on Google Earth imagery, along 130 Sampling Units of 250 m long river stretches. Eight riparian structural indicators, related with lateral dimension, weighted area and shape complexity of riparian patches were calculated using Patch Analyst extension for ArcGis 10. A set of 29 hydrological, climatic, and hydrogeomorphological variables were computed, by a water modelling system (MOHID), using monthly meteorological data between 2008 and 2014. Land-use classes were also calculated, in a 250m-buffer surrounding each sampling unit, using a classification based system on Corine Land Cover. Boosted Regression Trees identified Mean-width (MW) as the optimal riparian indicator for water scarcity and drought, followed by the Weighted Class Area (WCA) (classification accuracy =0.79 and 0.69 respectively). Average Flow and Strahler number were consistently selected, by all boosted models, as the most important explanatory variables. However, a combined effect of hidrogeomorphology and land-use can explain the high variability found in the riparian width mainly in Tâmega tributaries. Riparian patches are larger towards Tâmega river mouth although with lower shape complexity, probably related with more continuous and almost monospecific stands. Climatic, hydrological and land use scenarios, singly and combined, were used to quantify the riparian variability responding to these changes, and to assess the loss of riparian

  3. Morphological evolution of a rural headwater stream after channelisation

    Science.gov (United States)

    Landemaine, Valentin; Gay, Aurore; Cerdan, Olivier; Salvador-Blanes, Sébastien; Rodrigues, Stéphane

    2015-02-01

    In recent decades, stream valleys have been profoundly modified by the construction of weirs and dams and by channelisation. Channelisation modifies the morphology of streams and induces changes in their energy regime and sediment transport capacity. These types of changes in the channel morphology have to be quantified to allow the implementation of management strategies to regulate sediment transfer. However, studies over an entire stream using historical comparisons remain scarce, and the associated uncertainties have not yet been resolved. In this study, the sedimentary response to channelisation on a medium time scale (42 years) of a French river known as the Ligoire is investigated. This river is the main channel of a small rural headwater catchment that has been channelised over 21 km. We have used the historical cross sections before and after channelisation and the current ones, and the objectives of this study were as follows: (1) to develop a methodology of cross section superposition and the associated uncertainties; (2) to quantify the erosion and aggradation processes in the bed and on the banks along the bed profile; and (3) to calculate a sediment budget for the entire stream and determine the relative contributions of the banks and the streambed to this budget. A comparison of the cross sections before and after the channelisation shows that the morphology of the stream has been completely altered: the main channel length was reduced by 10%, the bankfull width was increased on average by 63%, and the slopes were smoothed. A total of 60,000 m3 of sediments was excavated during the channelisation works. Our results indicate that erosion is the dominant process: over 63% of its length, the streambed was incised by 0.41 m on average; and over 60% of its length, the banks were eroded by 0.20 m on average. The successive patterns of erosion and deposition along the stream are the result of the cumulative effects of channelisation and of the presence of

  4. Woody species composition, diversity and structure of riparian forests of four watercourses types in Burkina Faso

    Institute of Scientific and Technical Information of China (English)

    Oumarou Sambaré; Fidèle Bognounou; Rüdiger Wittig; Adjima Thiombiano

    2011-01-01

    Riparian forests are classified as endangered ecosystems in general, particularly in sahelian countries like Burkina Faso because of human-induced alterations and civil engineering works. The modification of this important habitat is continuing, with little attention being paid to the ecological or human consequences of these changes. The objective of this study is to describe the variation of woody species diversity and dynamic in riparian forests on different type of watercourse banks along phytogeographical gradient in Burkina Faso. All woody species were systematically measured in 90 sample plots with sides of 50 m × 20 m.Density, dominance, frequency and species and family importance values were computed to characterize the species composition. Different diversity indices were calculated to examine the heterogeneity of riparian forests. A total of 196 species representing 139 genera and 51 families were recorded in the overall riparian forests. The species richness of individuals with dbh ≥ 5cm increased significantly from the North to the South along the phytogeographical gradient and varied significantly between the different types of riparian forests. Similarity in tree species composition between riparian forests was low, which indicates high beta diversity and reflects differences in habitat conditions and topography.The structural characteristics varied significantly along the phytogeographical gradient and between the different types of riparian forests.The diameter class distribution of trees in all riparian forests showed a reverse “J” shaped curve except riparian forest of stream indicating vegetation dominated by juvenile individuals. Considering the ecological importance of riparian forest, there is a need to delineate and classify them along watercourses throughout the country.

  5. Structure and composition of altered riparian forests in an agricultural Amazonian landscape.

    Science.gov (United States)

    Nagy, R Chelsea; Porder, Stephen; Neill, Christopher; Brando, Paulo; Quintino, Raimundo Mota; do Nascimento, Sebastiâo Aviz

    2015-09-01

    Deforestation and fragmentation influence the microclimate, vegetation structure, and composition of remaining patches of tropical forest. In the southern Amazon, at the frontier of cropland expansion, forests are converted and fragmented in a pattern that leaves standing riparian forests whose dimensions are mandated by the Brazilian National Forest Code. These altered riparian forests share many characteristics of well-studied upland forest fragments, but differ because they remain connected to larger areas of forest downstream, and because they may experience wetter soil conditions because reduction of forest cover in the surrounding watershed raises groundwater levels and increases stream runoff. We compared forest regeneration, structure, composition, and diversity in four areas of intact riparian forest and four areas each of narrow, medium, and wide altered riparian forests that have been surrounded by agriculture since the early 1980s. We found that seedling abundance was reduced by as much as 64% and sapling abundance was reduced by as much as 67% in altered compared to intact riparian forests. The most pronounced differences between altered and intact forest occurred near forest edges and within the narrowest sections of altered riparian forests. Woody plant species composition differed and diversity was reduced in altered forests compared to intact riparian forests. However, despite being fragmented for several decades, large woody plant biomass and carbon storage, the number of live or dead large woody plants, mortality rates, and the size distribution of woody plants did not differ significantly between altered and intact riparian forests. Thus, even in these relatively narrow forests with high edge: area ratios, we saw no evidence of the increases in mortality and declines in biomass that have been found in other tropical forest fragment studies. However, because of the changes in both species community and reduced regeneration, it is unclear how long

  6. The role of hydrochory in structuring riparian and wetland vegetation.

    Science.gov (United States)

    Nilsson, Christer; Brown, Rebecca L; Jansson, Roland; Merritt, David M

    2010-11-01

    Hydrochory, or the passive dispersal of organisms by water, is an important means of propagule transport, especially for plants. During recent years, knowledge about hydrochory and its ecological consequences has increased considerably and a substantial body of literature has been produced. Here, we review this literature and define the state of the art of the discipline. A substantial proportion of species growing in or near water have propagules (fruits, seeds or vegetative units) able to disperse by water, either floating, submerged in flowing water, or with the help of floating vessels. Hydrochory can enable plants to colonize sites out of reach with other dispersal vectors, but the timing of dispersal and mechanisms of establishment are important for successful establishment. At the population level, hydrochory may increase the effective size and longevity of populations, and control their spatial configuration. Hydrochory is also an important source of species colonizing recruitment-limited riparian and wetland communities, contributing to maintenance of community species richness. Dispersal by water may even influence community composition in different landscape elements, resulting in landscape-level patterns. Genetically, hydrochory may reduce spatial aggregation of genetically related individuals, lead to high gene flow among populations, and increase genetic diversity in populations receiving many propagules. Humans have impacted hydrochory in many ways. For example, dams affect hydrochory by reducing peak flows and hence dispersal capacity, altering the timing of dispersal, and by presenting physical barriers to dispersal, with consequences for riverine plant communities. Hydrochory has been inferred to be an important vector for the spread of many invasive species, but there is also the potential for enhancing ecosystem restoration by improving or restoring water dispersal pathways. Climate change may alter the role of hydrochory by modifying the

  7. Variation and Genetic Structure in Platanus mexicana (Platanaceae along Riparian Altitudinal Gradient

    Directory of Open Access Journals (Sweden)

    Dulce M. Galván-Hernández

    2015-01-01

    Full Text Available Platanus mexicana is a dominant arboreal species of riparian ecosystems. These ecosystems are associated with altitudinal gradients that can generate genetic differences in the species, especially in the extremes of the distribution. However, studies on the altitudinal effect on genetic variation to riparian species are scarce. In Mexico, the population of P. mexicana along the Colipa River (Veracruz State grows below its reported minimum altitude range, possibly the lowest where this tree grows. This suggests that altitude might be an important factor in population genetics differentiation. We examined the genetic variation and population structuring at four sites with different altitudes (70, 200, 600 and 1700 m a.s.l. using ten inter-simple sequence repeats (ISSR markers. The highest value for Shannon index and Nei’s gene diversity was obtained at 1700 m a.s.l. (He = 0.27, Ne = 1.47, I = 0.42 and polymorphism reached the top value at the middle altitude (% p = 88.57. Analysis of molecular variance (AMOVA and STRUCTURE analysis indicated intrapopulation genetic differentiation. The arithmetic average (UPGMA dendrogram identified 70 m a.s.l. as the most genetically distant site. The genetic structuring resulted from limited gene flow and genetic drift. This is the first report of genetic variation in populations of P. mexicana in Mexico. This research highlights its importance as a dominant species, and its ecological and evolutionary implications in altitudinal gradients of riparian ecosystems.

  8. Impact of riparian land-use patterns on Ephemeroptera community structure in river basins of the southern Western Ghats, India

    Directory of Open Access Journals (Sweden)

    Selvakumar C.

    2014-02-01

    Full Text Available This study analysed the impact of riparian land use in structuring the larval ephemeropteran communities from 25 sites in streams and rivers of Kalakad-Mundanthurai Tiger Reserve (KMTR of the southern end of the Western Ghats, India. A total of twenty-eight species belonging to twenty-four genera of six families were collected across all the sites. Baetidae and Leptophlebiidae were the most numerous and ubiquitous families, comprising eight genera in each family and eleven and nine species, respectively. The physico-chemical parameters and species richness and abundance of mayflies varied across streams and rivers with different riparian land-use types. Species distribution was influenced by the environmental gradients. Canonical Correspondence Analysis revealed a clear separation of the mayfly assemblages along water quality and riparian land-use gradients. The results of this study suggest that Ephemeroptera taxa can be potentially used as sensitive indicators of riparian land use in lotic ecosystems.

  9. The influence of riparian vegetation on the energy input of the rivers Lafnitz and Pinka

    Science.gov (United States)

    Holzapfel, Gerda; Rauch, Hans Peter; Weihs, Philipp; Trimmel, Heidelinde; Formayer, Herbert; Leitner, Patrick; Graf, Wolfram; Melcher, Andreas; Dossi, Florian

    2013-04-01

    In Central Europe freshwater ecosystems have to deal with a loss of habitat structures due to channelisation and standardisation. Unimpaired streams and rivers are very rare, which leads to a few, remaining populations of sensitive invertebrate species which are severely fragmented. This progress is mainly noticed in lowland rivers in agricultural intensely used areas, where habitat degradation and pollution affect the ecosystems. Additional pressures on the freshwater systems will be expected due to climate change effects. In the Austrian Lowlands, an increase of air temperature about 2-2.5 °C is predicted till 2040. This will in turn lead to the highest increase in water temperature in the lowland rivers of the "Hungarian Plains", Ecoregion 11 on which the impacts of climate change will most likely be highest in Austria. Global warming on its own may lead to severe changes in aquatic ecosystems. Human impacts increase the negative effects even more. Main factors for a sustainable survival of benthic invertebrates and fishes are closely connected with parameters like water temperature, the availability of oxygen and nutrients, or radiation and nutrients for primary production which are closely related to climate. Natural bank vegetation reduces the influx of solar radiation as well as it forms a microclimate of its own and could provide very important niches for terrestrial and aquatic stages. Riparian areas with trees provide direct shade for the water body and thus avoiding the corresponding increase in water temperature. Wide riparian wooded areas can even decrease evaporation and increase the relative air humidity, which contributes to reducing water temperature. Input of deadwood like trees or logs represents essential habitats for invertebrates and fish assemblages. Its presence is one essential drivers of bed-morphology creating heterogeneous instream habitat patterns. In the framework of the project BIO_CLIC the potential of riparian vegetation to

  10. Inundation and Fire Shape the Structure of Riparian Forests in the Pantanal, Brazil

    Science.gov (United States)

    Arruda, Wellinton de Sá; Oldeland, Jens; Paranhos Filho, Antonio Conceição; Pott, Arnildo; Cunha, Nicolay L.; Ishii, Iria Hiromi; Damasceno-Junior, Geraldo Alves

    2016-01-01

    Inundation and fire can affect the structure of riparian vegetation in wetlands. Our aim was to verify if there are differences in richness, abundance, basal area, composition and topographic preference of woody species in riparian forests related to the fire history, flooding duration, or the interaction between both. The study was conducted in the riparian forests of the Paraguay River some of which were burned three times between 2001 and 2011. We sampled trees with a girth of at least 5 cm at breast height in 150 5 × 10 m plots (79 burned and 71 unburned). We also measured height of the flood mark and estimated the flooding duration of each plot. We performed Generalized Linear Mixed Models to verify differences in richness, basal area, and abundance of individuals associated to interaction of fire and inundation. We used an analysis of similarity (ANOSIM) and indicator species analysis to identify differences in composition of species and the association with burned and unburned area according to different levels of inundation. Finally, we used a hierarchical set of Generalized Linear Models (GLM), the so-called HOF models, to analyse each species’ specific response to inundation based on topography and to determine their preferred optimal topographic position for both burned as well as unburned areas. Richness was positively associated with elevation only in burned areas while abundance was negatively influenced by inundation only in burned areas. Basal area was negatively associated with time of inundation independent of fire history. There were 15 species which were significant indicators for at least one combination of the studied factors. We found nine species in burned areas and 15 in unburned areas, with response curves in HOF models along the inundation gradient. From these, five species shifted their optimal position along the inundation gradient in burned areas. The interaction of fire and inundation did not appear to affect the basal area, but it

  11. Quantifying riparian zone structure from airborne LiDAR: Vegetation filtering, anisotropic interpolation, and uncertainty propagation

    Science.gov (United States)

    Hutton, Christopher; Brazier, Richard

    2012-06-01

    SummaryAdvances in remote sensing technology, notably in airborne Light Detection And Ranging (LiDAR), have facilitated the acquisition of high-resolution topographic and vegetation datasets over increasingly large areas. Whilst such datasets may provide quantitative information on surface morphology and vegetation structure in riparian zones, existing approaches for processing raw LiDAR data perform poorly in riparian channel environments. A new algorithm for separating vegetation from topography in raw LiDAR data, and the performance of the Elliptical Inverse Distance Weighting (EIDW) procedure for interpolating the remaining ground points, are evaluated using data derived from a semi-arid ephemeral river. The filtering procedure, which first applies a threshold (either slope or elevation) to classify vegetation high-points, and second a regional growing algorithm from these high-points, avoids the classification of high channel banks as vegetation, preserving existing channel morphology for subsequent interpolation (2.90-9.21% calibration error; 4.53-7.44% error in evaluation for slope threshold). EIDW, which accounts for surface anisotropy by converting the remaining elevation points to streamwise co-ordinates, can outperform isoptropic interpolation (IDW) on channel banks, however, performs less well in isotropic conditions, and when local anisotropy is different to that of the main channel. A key finding of this research is that filtering parameter uncertainty affects the performance of the interpolation procedure; resultant errors may propagate into the Digital Elevation Model (DEM) and subsequently derived products, such as Canopy Height Models (CHMs). Consequently, it is important that this uncertainty is assessed. Understanding and developing methods to deal with such errors is important to inform users of the true quality of laser scanning products, such that they can be used effectively in hydrological applications.

  12. Riparian Inventory

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset is a digital representation of the 1:24,000 Land Use Riparian Areas Inventory for the state of Kansas. The dataset includes a 100 foot buffer around...

  13. Structure and Composition of Old-Growth and Unmanaged Second-Growth Riparian Forests at Redwood National Park, USA

    Directory of Open Access Journals (Sweden)

    Christopher R. Keyes

    2014-02-01

    Full Text Available Restoration of second-growth riparian stands has become an important issue for managers of redwood (Sequoia sempervirens [D. Don] Endl. forest reserves. Identifying differences between old-growth and second-growth forest vegetation is a necessary step in evaluating restoration needs and targets. The objective of this study was to characterize and contrast vegetation structure and composition in old-growth and unmanaged second-growth riparian forests in adjacent, geomorphologically similar watersheds at Redwood National Park. In the old-growth, redwood was the dominant overstory species in terms of stem density, basal area, and importance values. Second-growth was dominated by red alder (Alnus rubra Bong., Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco, and redwood. Understory species were similar in both forests, with several key differences: Oxalis oregana Nutt. and Trillium ovatum Pursh had greater importance values in the old-growth, and Vaccinium parvifolium Sm., Dryopteris spp. and sedges Carex spp. had greater importance values in the second-growth. Notable differences in structure and composition suggest that restoration practices such as thinning could expedite the acquisition of old-growth characteristics in second-growth riparian forests.

  14. Assessing Anthropogenic Influence and Edge Effect Influence on Forested Riparian Buffer Spatial Configuration and Structure: An Example Using Lidar Remote Sensing Methods

    Science.gov (United States)

    Wasser, L. A.; Chasmer, L. E.

    2012-12-01

    Forested riparian buffers (FRB) perform numerous critical ecosystem services. However, globally, FRB spatial configuration and structure have been modified by anthropogenic development resulting in widespread ecological degradation as seen in the Gulf of Mexico and the Chesapeake Bay. Riparian corridors within developed areas are particularly vulnerable to disturbance given two edges - the naturally occurring stream edge and the matrix edge. Increased edge length predisposes riparian vegetation to "edge effects", characterized by modified physical and environmental conditions at the interface between the forested buffer and the adjacent landuse, or matrix and forest fragment degradation. The magnitude and distance of edge influence may be further influenced by adjacent landuse type and the width of the buffer corridor at any given location. There is a need to quantify riparian buffer spatial configuration and structure over broad geographic extents and within multiple riparian systems in support of ecologically sound management and landuse decisions. This study thus assesses the influence of varying landuse types (agriculture, suburban development and undeveloped) on forested riparian buffer 3-dimensional structure and spatial configuration using high resolution Light Detection and Ranging (LiDAR) data collected within a headwater watershed. Few studies have assessed riparian buffer structure and width contiguously for an entire watershed, an integral component of watershed planning and restoration efforts such as those conducted throughout the Chesapeake Bay. The objectives of the study are to 1) quantify differences in vegetation structure at the stream and matrix influenced riparian buffer edges, compared to the forested interior and 2) assess continuous patterns of changes in vegetation structure throughout the buffer corridor beginning at the matrix edge and ending at the stream within buffers a) of varying width and b) that are adjacent to varying landuse

  15. Assessing the Effects of Periodic Flooding on the Population Structure and Recruitment Rates of Riparian Tree Forests

    Directory of Open Access Journals (Sweden)

    Jean-Sébastien Berthelot

    2014-08-01

    Full Text Available Riparian forest stands are subjected to a variety of hydrological stresses as a result of annual fluctuations in water levels during the growing season. Spring floods create additional water-related stress as a result of a major inflow of water that floods riverside land. This exploratory study assesses the impacts of successive floods on tree dynamics and regeneration in an active sedimentation area, while determining the age of the stands using the recruitment rates, tree structure and tree rings based on dendrochronological analysis. Environmental data were also recorded for each vegetation quadrat. In total, 2633 tree stems were tallied throughout the quadrats (200 m2, and tree specimens were analyzed based on the various flood zones. A total of 720 specimens were counted (100 m2 strip to measure natural regeneration. Higher recruitment rates are noted for the no-flood zones and lower rates in active floodplains. During the period of the establishment of tree species, the survival rates are comparable between the flood zones and the no-flood zones. Tree diameter distribution reveals a strong predominance of young trees in flooded areas. Different factors appear to come into play in the dynamics of riparian forest stands, including the disruptions associated with successive flooding.

  16. Groundwater management institutions to protect riparian habitat

    Science.gov (United States)

    Orr, Patricia; Colby, Bonnie

    2004-12-01

    Groundwater pumping affects riparian habitat when it causes the water table to drop beyond the reach of riparian plants. Riparian habitat provides services that are not directly traded in markets, as is the case with many environmental amenities. There is no direct market where one may buy or sell the mix of services provided by a riparian corridor. The objective of this article is to review groundwater management mechanisms and assess their strengths and weaknesses for preserving the ecological integrity of riparian areas threatened by groundwater pumping. Policy instruments available to those concerned with the effects of groundwater pumping on riparian areas fall into three broad categories: (1) command and control (CAC), (2) incentive-based economic instruments, and (3) cooperative/suasive strategies. The case of the San Pedro River illustrates multiple and overlapping strategies applied in an ongoing attempt to reverse accumulating damage to a riparian ecosystem. Policy makers in the United States can choose among a broad menu of policy options to protect riparian habitat from groundwater pumping. They can capitalize on the clarity of command-and-control strategies, the flexibility and less obtrusive nature of incentive-based economic strategies, and the benefits that collaborative efforts can bring in the form of mutual consideration. While collaborative problem solving and market-based instruments are important policy tools, experience indicates that a well-formulated regulatory structure to limit regional groundwater pumping is an essential component of an effective riparian protection strategy.

  17. Riparian Wetlands: Mapping

    Science.gov (United States)

    Riparian wetlands are critical systems that perform functions and provide services disproportionate to their extent in the landscape. Mapping wetlands allows for better planning, management, and modeling, but riparian wetlands present several challenges to effective mapping due t...

  18. Riparian plant community structure in a managed hydrological regime. University of Wyoming National Park Service Research Center Annual Report

    Science.gov (United States)

    Mellman-Brown, Sabine; Roberts, Dave; Pugesek, Bruce H.

    2008-01-01

    The hydrology of the Snake River in Grand Teton National Park is partly determined by releases from Jackson Lake Dam. The dam was first built in 1908 and became part of the National Park system when GTNP was expanded to include most of Jackson Hole. Completion of the present structure of Jackson Lake Dam occurred in 1917 and resulted in an increase above the natural level of Jackson Lake of 11.9 m. The Bureau of Reclamation (BOR) manages the dam and sets discharge schedules, primarily to meet agricultural needs, and to a lesser extent the needs of recreational river use. Major changes to the hydrological regime of the Snake River include lower than natural peak releases, decrease in frequency of extreme flood events , and unusually high flows from July to September. In addition , peak releases prior to 1957 were not synchronized with spring runoff but shifted to July or early August. Changes in inundation frequencies of floodplains , inundation duration and timing of peak flows have profound effects on the extent and composition of the riparian zone.

  19. Structural and functional response of methane-consuming microbial communities to different flooding regimes in riparian soils

    Science.gov (United States)

    Bodelier, Paul LE; Bär-Gilissen, Marie-Jose; Meima-Franke, Marion; Hordijk, Kees

    2012-01-01

    Climate change will lead to more extreme precipitation and associated increase of flooding events of soils. This can turn these soils from a sink into a source of atmospheric methane. The latter will depend on the balance of microbial methane production and oxidation. In the present study, the structural and functional response of methane oxidizing microbial communities was investigated in a riparian flooding gradient. Four sites differing in flooding frequency were sampled and soil-physico-chemistry as well as methane oxidizing activities, numbers and community composition were assessed. Next to this, the active community members were determined by stable isotope probing of lipids. Methane consumption as well as population size distinctly increased with flooding frequency. All methane consumption parameters (activity, numbers, lipids) correlated with soil moisture, organic matter content, and conductivity. Methane oxidizing bacteria were present and activated quickly even in seldom flooded soils. However, the active species comprised only a few representatives belonging to the genera Methylobacter, Methylosarcina, and Methylocystis, the latter being active only in permanently or regularly flooded soils. This study demonstrates that soils exposed to irregular flooding harbor a very responsive methane oxidizing community that has the potential to mitigate methane produced in these soils. The number of active species is limited and dominated by one methane oxidizing lineage. Knowledge on the characteristics of these microbes is necessary to assess the effects of flooding of soils and subsequent methane cycling therein. PMID:22408730

  20. Unravelling the role of allochthonous aquatic resources to food web structure in a tropical riparian forest.

    Science.gov (United States)

    Recalde, Fátima C; Postali, Thaís C; Romero, Gustavo Q

    2016-03-01

    The role of matter and energy flow across ecosystem boundaries for the subsidized consumer populations is well known. However, little is known on the effects of allochthonous subsidies on food web structure and trophic niche dimensions of consumers in the tropics. We excluded allochthonous aquatic insects from tropical streams using greenhouse-type exclosures to test the influence of aquatic allochthonous subsidies on the trophic structure and niche dimensions of terrestrial predators using stable isotope methods. In exclosure treatments, abundance and biomass of terrestrial predators, and biomass of phytophages decreased and increased, respectively. Vegetation-living predators were more responsive to allochthonous inputs than those living on the ground. Overall, lower availability of allochthonous inputs did not affect community-wide metrics and niche width of predators. However, the niche width of some spider families had very low overlap between treatments, and others had wider isotopic niches in the control than in the exclusion treatment. Most of the C and N in predators living in control stretches came from aquatic subsidies, and those predators living in the exclusion treatments switched their diets to terrestrial sources, showing a preference of predators for allochthonous subsidies. Our results suggest that allochthonous subsidies are also relevant to tropical fauna living upon vegetation. Moreover, allochthonous resources may amplify the niche dimension of certain predators or considerably change the trophic niche of others. Our study highlights the importance of including modern isotopic tools in elucidating the role of allochthonous resources on the patterns of trophic structure and niche dimensions of consumers from donor ecosystems. PMID:26590144

  1. Riparian forestry management and adult stream insects

    Directory of Open Access Journals (Sweden)

    R. A. Briers

    2004-01-01

    Full Text Available The impacts of coniferous plantation forestry on the biology of upland streams in the UK are firmly established. Whilst benthic communities have been well studied, very little research has considered the impacts of riparian forestry management on adult stream insects, yet the essentially terrestrial adult (reproductive phase may be important in determining the abundance and distribution of larval stages. Riparian vegetation has a potentially strong impact on survival and success of adult stages through alteration of microclimate, habitat structure and potential food sources, in addition to effects carried over from larval stages. Here, current riparian management strategies are analysed in the light of available information on the ecology of adult stream insects. On the whole, management practices appear to favour adult stream insects, although an increase in tree cover in riparian areas could be beneficial, by providing more favourable microclimatic conditions for adults. This conclusion is drawn based on rather limited information, and the need for further research into the effects of riparian forestry management on adult stream insects is highlighted. Keywords: microclimate, plantation, life history, riparian vegetation

  2. Agriculture and riparian areas

    OpenAIRE

    Krueger, William C.

    1994-01-01

    Agriculture has historically been based in the subirrigated riparian ecosystems. Often the engineering and agricultural practices have altered the systems and many of the associated ecological processes. In the Western United States, the most common agricultural practices affecting riparian systems has been livestock grazing. Effects have been both positive and negative. Lack of management has deteriorated many of these systems. Current research has shown what types of management have been su...

  3. Evaluating the quality of riparian forest vegetation: the Riparian Forest Evaluation (RFV index

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    Fernando Magdaleno

    2014-08-01

    Full Text Available Aim of study: This paper presents a novel index, the Riparian Forest Evaluation (RFV index, for assessing the ecological condition of riparian forests. The status of riparian ecosystems has global importance due to the ecological and social benefits and services they provide. The initiation of the European Water Framework Directive (2000/60/CE requires the assessment of the hydromorphological quality of natural channels. The Directive describes riparian forests as one of the fundamental components that determine the structure of riverine areas. The RFV index was developed to meet the aim of the Directive and to complement the existing methodologies for the evaluation of riparian forests.Area of study: The RFV index was applied to a wide range of streams and rivers (170 water bodies inSpain.Materials and methods: The calculation of the RFV index is based on the assessment of both the spatial continuity of the forest (in its three core dimensions: longitudinal, transversal and vertical and the regeneration capacity of the forest, in a sampling area related to the river hydromorphological pattern. This index enables an evaluation of the quality and degree of alteration of riparian forests. In addition, it helps to determine the scenarios that are necessary to improve the status of riparian forests and to develop processes for restoring their structure and composition.Main results: The results were compared with some previous tools for the assessment of riparian vegetation. The RFV index got the highest average scores in the basins of northernSpain, which suffer lower human influence. The forests in central and southern rivers got worse scores. The bigger differences with other tools were found in complex and partially altered streams and rivers.Research highlights: The study showed the index’s applicability under diverse hydromorphological and ecological conditions and the main advantages of its application. The utilization of the index allows a

  4. Using Airborne Lidar to Predict Leaf Area Index in Cottonwood Trees and Refine Riparian Water Use Estimates 1877

    Science.gov (United States)

    Quantification of riparian forest structure is important for developing a better understanding of how riparian forest ecosystems function. Additionally, estimation of riparian forest structural attributes, such as Leaf Area Index (LAI), is an important step in identifying the amount of water use in ...

  5. Assessing the Utility of Green LiDAR for Characterizing Forest Canopy Structure and Stream Bathymetry in Riparian Zones.

    Science.gov (United States)

    Moskal, L. M.; Richardson, J.

    2014-12-01

    Forested riparian zones serve many ecosystem functions from species habitat through stream shading and large woody debris recruitment, to improvements in water quality. Moreover, stream depth and bathymetry in forested environments is difficult and costly to measure in the field, but critically important for stream-dwelling organisms. Green (bathymetric) LiDAR (G-L) can be used to characterize stream bathymetry, but little is known of its ability to accurately characterize stream bathymetry in narrow (width less than 5 m), heavily forested streams. Canopy characterization with green LiDAR is also poorly understood. We compared canopy and digital elevation models (DEMs) derived from green and near-infrared LiDAR (NIR-L) to field measurements in a narrow, forested stream in Oregon, USA, as well as comparing the two canopy models and DEMs to each other along the length of the stream and to estimates of leaf area index. We observed that the canopy models from the G-L are lower in accuracy compared to NIR-L canopy models. Canopy height models from the G-L were up to 26% less accurate in dense stands, compared to the NIR-L accuracy of 94%. We attribute these errors in part to the lower quality of DEMs generated from the G-L as compared to the NIR-L DEMs. As for bathymetry, the G-L DEM was 0.05 cm higher in elevation than the field measured stream elevation, while the NIR-L ground model was 0.17mm higher. The elevation difference tended to increase with stream depth for both types of LiDAR-derived DEMs, but stream depth only explained a small portion of the variability (coefficient of determination equals 0.09 for NIR-L DEM and 0.05 for G-L DEM). Our results suggest that G-L may be limited in accurately characterizing the bathymetry of narrow streams in heavily forested environments due to difficulty penetrating canopy and interactions with complex topography.

  6. Validating LiDAR Derived Estimates of Canopy Height, Structure and Fractional Cover in Riparian Areas: A Comparison of Leaf-on and Leaf-off LiDAR Data

    Science.gov (United States)

    Wasser, L. A.; Chasmer, L. E.; Taylor, A.; Day, R.

    2010-12-01

    Characterization of riparian buffers is integral to understanding the landscape scale impacts of disturbance on wildlife and aquatic ecosystems. Riparian buffers may be characterized using in situ plot sampling or via high resolution remote sensing. Field measurements are time-consuming and may not cover a broad range of ecosystem types. Further, spectral remote sensing methods introduce a compromise between spatial resolution (grain) and area extent. Airborne LiDAR can be used to continuously map and characterize riparian vegetation structure and composition due to the three-dimensional reflectance of laser pulses within and below the canopy, understory and at the ground surface. The distance between reflections (or ‘returns’) allows for detection of narrow buffer corridors at the landscape scale. There is a need to compare leaf-off and leaf-on surveyed LiDAR data with in situ measurements to assess accuracy in landscape scale analysis. These comparisons are particularly important considering increased availability of leaf-off surveyed LiDAR datasets. And given this increased availability, differences between leaf-on and leaf-off derived LiDAR metrics are largely unknown for riparian vegetation of varying composition and structure. This study compares the effectiveness of leaf-on and leaf-off LiDAR in characterizing riparian buffers of varying structure and composition as compared to field measurements. Field measurements were used to validate LiDAR derived metrics. Vegetation height, canopy cover, density and overstory and understory species composition were recorded in 80 random plots of varying vegetation type, density and structure within a Pennsylvania watershed (-77.841, 40.818). Plot data were compared with LiDAR data collected during leaf on and leaf off conditions to determine 1) accuracy of LiDAR derived metrics compared to field measures and 2) differences between leaf-on and leaf-off LiDAR metrics. Results illustrate that differences exist between

  7. Edaphic, salinity, and stand structural trends in chronosequences of native and non-native dominated riparian forests along the Colorado River, USA

    Science.gov (United States)

    Merritt, David M.; Shafroth, Patrick B.

    2012-01-01

    Tamarix spp. are introduced shrubs that have become among the most abundant woody plants growing along western North American rivers. We sought to empirically test the long-held belief that Tamarix actively displaces native species through elevating soil salinity via salt exudation. We measured chemical and physical attributes of soils (e.g., salinity, major cations and anions, texture), litter cover and depth, and stand structure along chronosequences dominated by Tamarix and those dominated by native riparian species (Populus or Salix) along the upper and lower Colorado River in Colorado and Arizona/California, USA. We tested four hypotheses: (1) the rate of salt accumulation in soils is faster in Tamarix-dominated stands than stands dominated by native species, (2) the concentration of salts in the soil is higher in mature stands dominated by Tamarix compared to native stands, (3) soil salinity is a function of Tamarix abundance, and (4) available nutrients are more concentrated in native-dominated stands compared to Tamarix-dominated stands. We found that salt concentration increases at a faster rate in Tamarix-dominated stands along the relatively free-flowing upper Colorado but not along the heavily-regulated lower Colorado. Concentrations of ions that are known to be preferentially exuded by Tamarix (e.g., B, Na, and Cl) were higher in Tamarix stands than in native stands. Soil salt concentrations in older Tamarix stands along the upper Colorado were sufficiently high to inhibit germination, establishment, or growth of some native species. On the lower Colorado, salinity was very high in all stands and is likely due to factors associated with floodplain development and the hydrologic effects of river regulation, such as reduced overbank flooding, evaporation of shallow ground water, higher salt concentrations in surface and ground water due to agricultural practices, and higher salt concentrations in fine-textured sediments derived from naturally saline

  8. Effects of reintroduced beaver (Castor canadensis) on riparian bird community structure along the upper San Pedro River, southeastern Arizona and northern Sonora, Mexico

    Science.gov (United States)

    Johnson, Glenn E.; van Riper, Charles, III

    2014-01-01

    Chapter 1.—We measured bird abundance and richness along the upper San Pedro River in 2005 and 2006, in order to document how beavers (Castor canadensis) may act as ecosystem engineers after their reintroduction to a desert riparian area in the Southwestern United States. In areas where beavers colonized, we found higher bird abundance and richness of bird groups, such as all breeding birds, insectivorous birds, and riparian specialists, and higher relative abundance of many individual species—including several avian species of conservation concern. Chapter 2.—We conducted bird surveys in riparian areas along the upper San Pedro River in southeastern Arizona (United States) and northern Sonora (Mexico) in order to describe factors influencing bird community dynamics and the distribution and abundance of species, particularly those of conservation concern. These surveys were also used to document the effects of the ecosystem-altering activities of a recently reintroduced beavers (Castor canadensis). Chapter 3.—We reviewed Southwestern Willow Flycatcher (Empidonax traillii extimus) nest records and investigated the potential for future breeding along the upper San Pedro River in southeastern Arizona, where in July 2005 we encountered the southernmost verifiable nest attempt for the species. Continued conservation and management of the area’s riparian vegetation and surface water has potential to contribute additional breeding sites for this endangered Willow Flycatcher subspecies. Given the nest record along the upper San Pedro River and the presence of high-density breeding sites to the north, the native cottonwood-willow forests of the upper San Pedro River could become increasingly important to E. t. extimus recovery, especially considering the anticipated effect of the tamarisk leaf beetle (Diorhabda carinulata) on riparian habitat north of the region.

  9. Riparian Habitat - Product of 2 riparian habitat workshops

    Data.gov (United States)

    California Department of Resources — In two riparian habitat workshops held between 2001 and 2002, scientists and managers identified the need for determining the scope of a consistent and acceptable...

  10. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  11. Influence of floods on natural riparian forests along the Ergis River,west China

    Institute of Scientific and Technical Information of China (English)

    CHENG Kewu; ZANG Runguo; ZHOU Xiaofang; ZHANG Weiyin; BAI Zhiqiang

    2007-01-01

    The riparian forests along the Ergis River,west China,composed mainly of Salicaceae species,play an important role in eco-environment protection and sustainable development of local agriculture,stockbreeding,and social economy of the northern desert region of Xinjiang Uygur Autonomous Region.The study of the influence of floods on the natural riparian forests is imperative for the understanding of the successional process and the acceleration of conservation and restoration of forests.By investigating the relationship between floods and dispersal of seeds,sprouting,natural regeneration,the structure of the forests,and their current distribution,we conclude that:1) the ripening and dispersal periods of Salicaceae species seeds overlap largely with flood occurrence periods,and the sprouting and natural regeneration of seeds depend greatly on flood events;2) floods supply soil water and increase groundwater level of riparian land through flood irrigation and horizontal infiltration to maintain the normal growth of the riparian forests;3) floods have a decisive influence on the structure,composition,and distribution pattern of riparian forests,and any disturbance in the water flow has a profound effect on these characteristics.Given these facts,some management measures for conservation and restoration of the riparian forests are proposed,including the establishment of riparian forest buffer belt,bank stabilization measures,and maintenance of flood protection.

  12. Effect of riparian vegetation cover and season on aquatic macroinvertebrate assemblages in the Ecuadorian Andes

    OpenAIRE

    Gallegos-Sánchez, Silvana Andrea

    2013-01-01

    The purpose of this study was to investigate the effects of season and changes in the riparian vegetation cover on diversity, structure, temporal variability, and trophic structure of aquatic macroinvertebrate assemblage in the Sambache River, Pasochoa Wildlife Refuge, Ecuador. Macroinvertebrate samples were collected using a Surber bottom sampler during the dry and rainy seasons from sections of the river dissecting three different riparian vegetation types with varying degrees of disturbanc...

  13. Can erosion control structures in large dryland arroyo channels lead to resilient riparian and cienega restoration? Observations from LiDAR, monitoring and modeling at Rancho San Bernardino, Sonora, MX

    Science.gov (United States)

    DeLong, S.; Henderson, W. M.

    2012-12-01

    The use of erosion control structures to mitigate or even reverse erosion and to restore ecological function along dryland channels (arroyos and gullies) has led to a long list of both successful and failed restoration efforts. We propose that successful implementation of "engineering" approaches to fluvial restoration that include in-channel control structures require either a quantitative approach to design (by scientists and engineers), or intimate on-the-ground knowledge, local observation, and a commitment to adapt and maintain restoration efforts in response to landscape change (by local land managers), or both. We further propose that the biophysical interactions among engineering, sedimentation, flood hydrology and vegetation reestablishment are what determine resilience to destructive extreme events that commonly cause erosion control structure failure. Our insights come from comprehensive monitoring of a remarkable experiment underway at Ranch San Bernardino, Sonora, MX. At this site, private landowners are working to restore ecosystem function to riparian corridors and former cieñega wetlands using cessation of grazing; vegetation planting; upland grass restoration; large scale rock gabions (up to 100 m wide) to encourage local sediment deposition and water storage; and large earthen berms (up to 900 m wide) with cement spillways that form reservoirs that fill rapidly with water and sediment. Well-planned and managed erosion control structures have been used elsewhere successfully in smaller gully networks, but we are unaware of a comparable attempt to use gabions and berms for the sole purpose of ecological restoration along >10 km of arroyo channels draining watersheds on the order of ~400 km2 and larger. We present an approach to monitoring the efficacy of arroyo channel restoration using terrestrial and airborne LiDAR, remote sensing, streamflow monitoring, shallow groundwater monitoring, hydrological modeling and field observation. Our methods

  14. [Floristic composition and distribution of the Andean subtropical riparian forests of Lules River, Tucuman, Argentina].

    Science.gov (United States)

    Sirombra, Martín G; Mesa, Leticia M

    2010-03-01

    We studied the floristic composition and distribution of the riparian forest of two hydrographical systems in a subtropical Andean region. Using uni and multivariate techniques, we tested the hypotheses that a differentiable riparian forest exists, composed by native vegetation typical of the Yungas phytogeographical province, and that the distribution of vegetation varied significantly with geomorphologic characteristics. Parallel transects along the water courses were used to collect presence-absence data of vegetation in eleven sites. Detrended Correspondence Analysis defined a group of common riparian species for the studied area (Solanum riparium, Phenax laevigatus, Tipuana tipu, Cestrum parqui, Carica quercifolia, Acacia macracantha, Celtis iguanaea, Juglans australis, Pisoniella arborescens, Baccharis salicifolia, Cinnamomum porphyrium and Eugenia uniflora) and identified two reference sites. The distribution of the riparian vegetation varied significantly with the geomorphic characteristics along the studied sites. Riparian habitats were composed by native and exotic species. A distinct riparian flora, different in structure and function from adjacent terrestrial vegetation, could not be identified. Riparian species were similar to the adjacent terrestrial strata. These species would not be limited by the proximity to the river. Anthropogenic impacts were important factors regulating the introduction and increase of exotic vegetation. The lack of regulation of some activities in the zone could cause serious problems in the integrity of this ecosystem. PMID:20411737

  15. Wetlands & Deepwater Habitats - Montana Wetland and Riparian Framework - Map Service

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — The Montana Wetland and Riparian Framework represents the extent, type, and approximate location of wetlands, riparian areas, and deepwater habitats in Montana....

  16. Riparian responses to extreme climate and land-use change scenarios.

    Science.gov (United States)

    Fernandes, Maria Rosário; Segurado, Pedro; Jauch, Eduardo; Ferreira, Maria Teresa

    2016-11-01

    Climate change will induce alterations in the hydrological and landscape patterns with effects on riparian ecotones. In this study we assess the combined effect of an extreme climate and land-use change scenario on riparian woody structure and how this will translate into a future risk of riparian functionality loss. The study was conducted in the Tâmega catchment of the Douro basin. Boosted Regression Trees (BRTs) were used to model two riparian landscape indicators related with the degree of connectivity (Mean Width) and complexity (Area Weighted Mean Patch Fractal Dimension). Riparian data were extracted by planimetric analysis of high spatial-resolution Word Imagery Layer (ESRI). Hydrological, climatic and land-use variables were obtained from available datasets and generated with process-based modeling using current climate data (2008-2014), while also considering the high-end RCP8.5 climate-change and "Icarus" socio-economic scenarios for the 2046-2065 time slice. Our results show that hydrological and land-use changes strongly influence future projections of riparian connectivity and complexity, albeit to diverse degrees and with differing effects. A harsh reduction in average flows may impair riparian zones while an increase in extreme rain events may benefit connectivity by promoting hydrologic dynamics with the surrounding floodplains. The expected increase in broad-leaved woodlands and mixed forests may enhance the riparian galleries by reducing the agricultural pressure on the area in the vicinity of the river. According to our results, 63% of river segments in the Tâmega basin exhibited a moderate risk of functionality loss, 16% a high risk, and 21% no risk. Weaknesses and strengths of the method are highlighted and results are discussed based on a resilience perspective with regard to riparian ecosystems. PMID:27341115

  17. Assessment of the buffer-induced setback effects on riparian scenic quality by digital tools

    OpenAIRE

    W-N Xiang

    1998-01-01

    Under a typical riparian landscape structure where a vegetated buffer is sandwiched between a greenway trail and the river bank or lake shore, a trail user's perceptions about riparian scenic quality are influenced by, among other factors, buffer-induced setback effects. As a trail is set back to leave enough space for the vegetated linear area, both the subject and the composition of a trail user's viewshed can change significantly. This may in turn affect his or her perceptions of the lakes...

  18. Ecological assessment of riparian forests in Benin

    NARCIS (Netherlands)

    Natta, A.K.

    2003-01-01

    The present research deals with the flora, phytosociology and ecology of riparian forests. The overall objective of this research is to contribute to a better knowledge of the flora, diversity and ecology of riparian forests inBenin

  19. Task-based performance analysis of FBP, SART and ML for digital breast tomosynthesis using signal CNR and Channelised Hotelling Observers.

    Science.gov (United States)

    Van de Sompel, Dominique; Brady, Sir Michael; Boone, John

    2011-02-01

    We assess the performance of filtered backprojection (FBP), the simultaneous algebraic reconstruction technique (SART) and the maximum likelihood (ML) algorithm for digital breast tomosynthesis (DBT) under variations in key imaging parameters, including the number of iterations, number of projections, angular range, initial guess, and radiation dose. This is the first study to compare these algorithms for the application of DBT. We present a methodology for the evaluation of DBT reconstructions, and use it to conduct preliminary experiments investigating trade-offs between the selected imaging parameters. This investigation includes trade-offs not previously considered in the DBT literature, such as the use of a stationary detector versus a C-arm imaging geometry. A real breast CT volume serves as a ground truth digital phantom from which to simulate X-ray projections under the various acquisition parameters. The reconstructed image quality is measured using task-based metrics, namely signal CNR and the AUC of a Channelised Hotelling Observer with Laguerre-Gauss basis functions. The task at hand is the detection of a simulated mass inserted into the breast CT volume. We find that the image quality in limited view tomography is highly dependent on the particular acquisition and reconstruction parameters used. In particular, we draw the following conclusions. First, we find that optimising the FBP filter design and SART relaxation parameter yields significant improvements in reconstruction quality from the same projection data. Second, we show that the convergence rate of the maximum likelihood algorithm, optimised with paraboloidal surrogates and conjugate gradient ascent (ML-PSCG), can be greatly accelerated using view-by-view updates. Third, we find that the optimal initial guess is algorithm dependent. In particular, we obtained best results with a zero initial guess for SART, and an FBP initial guess for ML-PSCG. Fourth, when the exposure per view is constant

  20. Geostatistical modeling of riparian forest microclimate and its implications for sampling

    Science.gov (United States)

    Eskelson, B.N.I.; Anderson, P.D.; Hagar, J.C.; Temesgen, H.

    2011-01-01

    Predictive models of microclimate under various site conditions in forested headwater stream - riparian areas are poorly developed, and sampling designs for characterizing underlying riparian microclimate gradients are sparse. We used riparian microclimate data collected at eight headwater streams in the Oregon Coast Range to compare ordinary kriging (OK), universal kriging (UK), and kriging with external drift (KED) for point prediction of mean maximum air temperature (Tair). Several topographic and forest structure characteristics were considered as site-specific parameters. Height above stream and distance to stream were the most important covariates in the KED models, which outperformed OK and UK in terms of root mean square error. Sample patterns were optimized based on the kriging variance and the weighted means of shortest distance criterion using the simulated annealing algorithm. The optimized sample patterns outperformed systematic sample patterns in terms of mean kriging variance mainly for small sample sizes. These findings suggest methods for increasing efficiency of microclimate monitoring in riparian areas.

  1. The inbuilt long-term unfeasibility of environmental flows when disregarding riparian vegetation requirements

    Directory of Open Access Journals (Sweden)

    R. Rivaes

    2015-10-01

    Full Text Available Environmental flows remain biased towards the traditional fish biological group and ignore the inter-annual flow variability that rules longer species life cycles, thus disregarding the long-term perspective of the riverine ecosystem. Incorporating riparian vegetation requirements into environmental flows could bring an important contribute to fill in this gap. The long-term after-effects of this shortcoming on the biological communities downstream of dams were never estimated before. We address this concern by evaluating the effects of environmental flow regimes disregarding riparian vegetation in the long-term perspective of the fluvial ecosystem. To achieve that purpose, the riparian vegetation evolution was modeled considering its structural response to a decade of different environmental flows, and the fish habitat availability was assessed for each of the resulting riparian habitat scenarios. We demonstrate that fish habitat availability changes accordingly to the long-term structural adjustments that riparian habitat endure following river regulation. Environmental flow regimes considering only aquatic biota become obsolete in few years due to the change of the habitat premises in which they were based on and, therefore, are unsustainable in the long run. Therefore, considering riparian vegetation requirements on environmental flows is mandatory to assure the effectiveness of those in the long-term perspective of the fluvial ecosystem.

  2. The inbuilt long-term unfeasibility of environmental flows when disregarding riparian vegetation requirements

    Science.gov (United States)

    Rivaes, R.; Boavida, I.; Santos, J. M.; Pinheiro, A. N.; Ferreira, M. T.

    2015-10-01

    Environmental flows remain biased towards the traditional fish biological group and ignore the inter-annual flow variability that rules longer species life cycles, thus disregarding the long-term perspective of the riverine ecosystem. Incorporating riparian vegetation requirements into environmental flows could bring an important contribute to fill in this gap. The long-term after-effects of this shortcoming on the biological communities downstream of dams were never estimated before. We address this concern by evaluating the effects of environmental flow regimes disregarding riparian vegetation in the long-term perspective of the fluvial ecosystem. To achieve that purpose, the riparian vegetation evolution was modeled considering its structural response to a decade of different environmental flows, and the fish habitat availability was assessed for each of the resulting riparian habitat scenarios. We demonstrate that fish habitat availability changes accordingly to the long-term structural adjustments that riparian habitat endure following river regulation. Environmental flow regimes considering only aquatic biota become obsolete in few years due to the change of the habitat premises in which they were based on and, therefore, are unsustainable in the long run. Therefore, considering riparian vegetation requirements on environmental flows is mandatory to assure the effectiveness of those in the long-term perspective of the fluvial ecosystem.

  3. The Influence of Salmon Recolonization on Riparian Communities in the Cedar River, Washington, USA

    Science.gov (United States)

    Moravek, J.; Clipp, H.; Kiffney, P.

    2015-12-01

    Salmon are a valuable cultural and economic resource throughout the Pacific Northwest, but increasing human activity is degrading coastal ecosystems and threatening local salmon populations. Salmon conservation efforts often focus on habitat restoration, including the re-colonization of salmon into historically obstructed areas such as the Cedar River in Washington, USA. However, to assess the implications of salmon re-colonization on a landscape scale, it is critical to consider not only the river ecosystem but also the surrounding riparian habitat. Although prior studies suggest that salmon alter riparian food web dynamics, the riparian community on the Cedar River has not yet been characterized. To investigate possible connections between salmon and the riparian habitat, we surveyed riparian spider communities along a gradient of salmon inputs (g/m2). In 10-m transects along the banks of the river, we identified spiders and spider webs, collected prey from webs, and characterized nearby aquatic macroinvertebrate communities. We found that the density of aquatic macroinvertebrates, as well as the density of spider prey, both had significant positive relationships with salmon inputs, supporting the hypothesis that salmon provide energy and nutrients for both aquatic and riparian food webs. We also found that spider diversity significantly decreased with salmon inputs, potentially due to confounding factors such as stream gradient or vegetation structure. Although additional information is needed to fully understand this relationship, the significant connection between salmon inputs and spider diversity is compelling motivation for further studies regarding the link between aquatic and riparian systems on the Cedar River. Understanding the connections between salmon and the riparian community is critical to characterizing the landscape-scale implications of sustainable salmon management in the Pacific Northwest.

  4. Importance of riparian remnants for frog species diversity in a highly fragmented rainforest.

    Science.gov (United States)

    Rodríguez-Mendoza, Clara; Pineda, Eduardo

    2010-12-23

    Tropical forests undergo continuous transformation to other land uses, resulting in landscapes typified by forest fragments surrounded by anthropogenic habitats. Small forest fragments, specifically strip-shaped remnants flanking streams (referred to as riparian remnants), can be particularly important for the maintenance and conservation of biodiversity within highly fragmented forests. We compared frog species diversity between riparian remnants, other forest fragments and cattle pastures in a tropical landscape in Los Tuxtlas, Mexico. We found similar species richness in the three habitats studied and a similar assemblage structure between riparian remnants and forest fragments, although species composition differed by 50 per cent. Frog abundance was halved in riparian remnants compared with forest fragments, but was twice that found in pastures. Our results suggest that riparian remnants play an important role in maintaining a portion of frog species diversity in a highly fragmented forest, particularly during environmentally stressful (hot and dry) periods. In this regard, however, the role of riparian remnants is complementary, rather than substitutive, with respect to the function of other forest fragments within the fragmented forest. PMID:20554561

  5. Recovery times of riparian vegetation

    Science.gov (United States)

    Vesipa, Riccardo; Camporeale, Carlo; Ridolfi, Luca

    2016-04-01

    Riparian vegetation is a key element in a number of processes that determine the eco-geomorphological features of the river landscape. Depending on the river water stage fluctuations, vegetation biomass randomly switches between growth and decay phases, and its biomass exhibits relevant temporal variations. A full understanding of vegetation dynamics is therefore only possible if the hydrological stochastic forcing is considered. In this vein, we focus on the recovery time of vegetation, namely the typical time taken by vegetation to recover a health state starting from a low biomass value (induced, for instance, by an intense flood). The minimalistic stochastic modeling approach is used for describing vegetation dynamics (i.e., the noise-driven alternation of growth and decay phases). The recovery time of biomass is then evaluated according to the theory of the mean first passage time in systems driven by dichotomous noise. The effect of the main hydrological and biological parameters on the vegetation recovery was studied, and the dynamics along the riparian transect was described in details. The effect of climate change and human interventions (e.g., river damming) was also investigated. We found that: (i) the oscillations of the river stage delay the recovery process (up to one order of magnitude, with respect to undisturbed conditions); (ii) hydrological/biological alterations (due to climate change, damming, exotic species invasion) modify the timescales of the recovery. The result provided can be a useful tool for the management of the river. They open the way to the estimation of: (i) the recovery time of vegetation after devastating floods, clear cutting or fires and; (ii) the timescale of the vegetation response to hydrological and biological alterations.

  6. Presence of riparian vegetation increases biotic condition of fish assemblages in two Brazilian reservoirs

    Directory of Open Access Journals (Sweden)

    Fabio Cop Ferreira

    2015-09-01

    Full Text Available Abstract The riparian vegetation in lakes and reservoirs is source of course wood structures such as trunks and branches and is used as sheltering, spawning and foraging habitats for fishes. The reduction of these submerged structures can thus, affect the composition and structure of fish assemblages in reservoirs. Aim To evaluate the influence of riparian vegetation on the biotic condition of fish assemblage by adapting the Reservoir Fish Assemblage Index (RFAI to two reservoirs in the Upper Paranapanema river basin, São Paulo State, Brazil. Methods The RFAI was adapted from metrics related to the functional characteristics and composition of fish assemblages through a protocol of metric selection and validation, and to its response to the presence of riparian vegetation. Results The final RFAI was composed by nine metrics, been lower in sites without riparian vegetation as consequence of the predominance of larger individuals and the percent of piscivorous and detritivorous fishes. Conclusions These results suggest that increasing shore habitat complexity in reservoirs by maintaining riparian vegetation increases fish biotic integrity.

  7. Hiawatha National Forest Riparian Inventory: A Case Study

    Science.gov (United States)

    Abood, S. A.

    2014-12-01

    Riparian areas are dynamic, transitional ecotones between aquatic and terrestrial ecosystems with well-defined vegetation and soil characteristics. Riparian areas offers wildlife habitat and stream water quality, offers bank stability and protects against erosions, provides aesthetics and recreational value, and other numerous valuable ecosystem functions. Quantifying and delineating riparian areas is an essential step in riparian monitoring, riparian management/planning and policy decisions, and in preserving its valuable ecological functions. Previous approaches to riparian areas mapping have primarily utilized fixed width buffers. However, these methodologies only take the watercourse into consideration and ignore critical geomorphology, associated vegetation and soil characteristics. Other approaches utilize remote sensing technologies such as aerial photos interpretation or satellite imagery riparian vegetation classification. Such techniques requires expert knowledge, high spatial resolution data, and expensive when mapping riparian areas on a landscape scale. The goal of this study is to develop a cost effective robust workflow to consistently map the geographic extent and composition of riparian areas within the Hiawatha National Forest boundary utilizing the Riparian Buffer Delineation Model (RBDM) v3.0 and open source geospatial data. This approach recognizes the dynamic and transitional natures of riparian areas by accounting for hydrologic, geomorphic and vegetation data as inputs into the delineation process and the results would suggests incorporating functional variable width riparian mapping within watershed management planning to improve protection and restoration of valuable riparian functionality and biodiversity.

  8. Riparian vegetation in South-western Europe: drivers of change across space and time (Invited)

    Science.gov (United States)

    Aguiar, F. C.; Ferriera, M.

    2010-12-01

    Riparian ecosystems of Mediterranean Europe have been largely disturbed for millennia due to human-driven alterations. Land-use, deforestation, water diversion and river regulation have been the major causes of change of riparian and freshwater ecosystems. Riparian vegetation in this region has particular features due to a large climatic and environmental variation; from the climatic harshness and the flash-flow hydrological regime of southern rivers to high-altitude permanent rivers of the north regions. Riparia is a fundamental element of the Mediterranean landscape by a number of ecological values, and economic and societal benefits, and they are usually seen as “linear oasis” embedded in the complex landscape matrix. We face a huge challenge in understanding the distribution trends of the riparian species assemblages in those diverse biogeographic regions and the varying effects of the multi-scaled drivers of change. I will review the main studies that have explored the patterns of variation of riparian plant assemblages across space and time in South-Western Europe, including its longitudinal and lateral dimension. Structural community features and plant functional traits, that can be described and quantified, are ecological expressions of both natural and human disturbances, and comparatively less understood than floral composition patterns, and many studies suggest that they are more reactive to disturbance. Linkages of taxonomic and functional trait variation will also be addressed, focusing in the influence of environment at various scale levels. Effects of human disturbances, particularly the alien plant invasions and the losses of biodiversity and connectivity will be tackled. These studies provided evidence of shifts in species composition and in structural complexity, as well as in individual and community responses to wetting and drying due to regulation and to physical disturbances of riverbanks. The intensive agriculture in adjacent lands is a

  9. Estimating Riparian ET through Remote Sensing

    Science.gov (United States)

    Samani, Z.; Bawazir, S.; Bleiweiss, M.; Skaggs, R.; Schmugge, T.

    2005-12-01

    Riparian evapotranspiration (ET) along the Rio Grande River has become a major hydrological as well as political issue in New Mexico. The State of New Mexico has spent millions of dollars in recent years to eradicate riparian vegetation without being able to quantify the change in regional ET. Many studies have focused on measuring evapotranspiration of individual riparian vegetation types, mainly saltcedar and native cottonwood. However, the riparian vegetation on the Middle Rio Grande varies in density and species.. Spatial variation in climate, soil type and depth to groundwater causes variation in ET, as well. It is obvious that in order to obtain more accuracy in measurements, multiple sampling points are needed; thus, making the process costly and impractical An alternative solution, which is also cost-effective, is measuring ET by using remote sensing technology. Remote sensing combines regional satellite data with localized ET measurement to calculate regional ET. REEM (Regional ET Estimation Model) is a process that uses the energy balance at the top of the canopy to estimate ET. REEM has been using ASTER images for values of surface temperature, albedo and NDVI to calculate net radiation (Rn), ground heat flux (G) and sensible heat flux (H). The ET is then calculated as residual of the energy components. The REEM model is being used to calculate regional ET values for the Riparian vegetation of the Middle Rio Grande. The paper compares the ET values for various vegetation types using remote sensing and ET derived from Eddy Covariance Flux Towers.

  10. Riparian zone hydrology and soil water total organic carbon (TOC)

    OpenAIRE

    T. Grabs; K. Bishop; Laudon, H.; Lyon, S. W.; Seibert, J.

    2012-01-01

    Groundwater flowing from hillslopes through riparian (near-stream) soils often undergoes chemical transformations that can substantially influence stream water chemistry. We used landscape analysis to predict total organic carbon (TOC) concentration profiles and groundwater levels measured in the riparian zone (RZ) of a 67 km2 catchment in Sweden. TOC exported laterally from 13 riparian soil profiles was then estimated based on the riparian flow–concentration integratio...

  11. Riparian Vegetation Mapping Along the Hanford Reach

    International Nuclear Information System (INIS)

    During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY2002

  12. Riparian Areas of the Southwest: Learning from Repeat Photographs

    Science.gov (United States)

    Zaimes, George N.; Crimmins, Michael A.

    2010-01-01

    Spatial and temporal variability of riparian areas, as well as potential impacts from climate change, are concepts that land and water managers and stakeholders need to understand to effectively manage and protect riparian areas. Rapid population growth in the southwestern United States, and multiple-use designation of most riparian areas, makes…

  13. A scientific assessment of the effectiveness of riparian management practices

    Science.gov (United States)

    The CEAP Riparian Team reviewed the influence of riparian management practices (RMP) on vegetation, soils and ecosystem services. We developed a conceptual model that links management practices to riparian vegetation and soil attributes and then links these attributes to ecosystem services such as w...

  14. Subtropical reservoir shorelines have reduced plant species and functional richness compared with adjacent riparian wetlands

    International Nuclear Information System (INIS)

    Dam construction has large negative effects on biodiversity in river and riparian ecosystems worldwide. This study aimed to determine whether reservoir shorelines had lower plant species diversity and functional diversity than unregulated or lightly regulated riparian wetlands and to examine the responses of plant diversity and functional traits to reservoir shoreline environmental gradients. We surveyed 146, 44, and 67 plots on reservoir shorelines and in mainstem and tributary riparian wetlands, respectively, in a subtropical river–reservoir system. Species richness, functional richness, evenness, and divergence were calculated to reflect the species and functional diversity of plant communities. Environmental factors including elevation above water level, slope, landform type, substrate, disturbance, and cover were measured. The results showed that both species and functional richness were significantly lower on reservoir shorelines than in riparian wetlands. The relative species number of clonal plants and relative cover of annual plants were both negatively related to slope and elevation. Structural equation modeling and other statistical analyses indicated that most environmental factors had significant effects on species and functional richness on reservoir shorelines but had no significant effect on functional evenness and divergence. Our findings suggest that reservoir shoreline wetlands formed by damming rivers and inundating pre-existing riparian wetlands can be a biodiversity coldspot in regulated rivers at the plot level. Topographic factors are important in determining the plant diversity and vegetation establishment on reservoir shorelines in the Yangtze River basin. (letter)

  15. Methods for evaluating riparian habitats with applications to management

    Science.gov (United States)

    Platts, William S.; Armour, C.L.; Booth, G.D.; Bryant, M.; Bufford, J.L.; Cuplin, P.; Jensen, S.; Lienkaemper, G.W.; Minshall, G.W.; Monsen, S.T.; Nelson, R.L.; Sedell, J.R.; Tuhy, J.S.

    1987-01-01

    Riparian area planning and management is a major national issues today--something that should have been the case a century ago. A century of additive effects of land use has resulted in major impacts on many riparian stream habitats and their fisheries, wildlife, and domestic livestock use. Before scientists can evaluate the influences of various land and water uses on riparian environments, they must first understand these environments. This means being able to detect and measure with confidence the natural and artificial variation and instantaneous conditions of the riparian habitat. These conditions must then be related to the production capability of riparian habitat and any extraneous factors affecting this production potential.

  16. Riparian Vegetation Mapping Along the Hanford Reach

    Energy Technology Data Exchange (ETDEWEB)

    FOGWELL, T.W.

    2003-07-11

    During the biological survey and inventory of the Hanford Site conducted in the mid-1990s (1995 and 1996), preliminary surveys of the riparian vegetation were conducted along the Hanford Reach. These preliminary data were reported to The Nature Conservancy (TNC), but were not included in any TNC reports to DOE or stakeholders. During the latter part of FY2001, PNNL contracted with SEE Botanical, the parties that performed the original surveys in the mid 1990s, to complete the data summaries and mapping associated with the earlier survey data. Those data sets were delivered to PNNL and the riparian mapping by vegetation type for the Hanford Reach is being digitized during the first quarter of FY2002. These mapping efforts provide the information necessary to create subsequent spatial data layers to describe the riparian zone according to plant functional types (trees, shrubs, grasses, sedges, forbs). Quantification of the riparian zone by vegetation types is important to a number of DOE'S priority issues including modeling contaminant transport and uptake in the near-riverine environment and the determination of ecological risk. This work included the identification of vegetative zones along the Reach by changes in dominant plant species covering the shoreline from just to the north of the 300 Area to China Bar near Vernita. Dominant and indicator species included Agropyron dasytachyudA. smithii, Apocynum cannabinum, Aristida longiseta, Artemisia campestris ssp. borealis var scouleriana, Artemisa dracunculus, Artemisia lindleyana, Artemisia tridentata, Bromus tectorum, Chrysothamnus nauseosus, Coreopsis atkinsoniana. Eleocharis palustris, Elymus cinereus, Equisetum hyemale, Eriogonum compositum, Juniperus trichocarpa, Phalaris arundinacea, Poa compressa. Salk exigua, Scirpus acutus, Solidago occidentalis, Sporobolus asper,and Sporobolus cryptandrus. This letter report documents the data received, the processing by PNNL staff, and additional data gathered in FY

  17. Preliminary indicators for restoration assessment in riparian reforestations

    Directory of Open Access Journals (Sweden)

    Daniele Nogueira dos Reis

    2014-12-01

    Full Text Available The restoration success in forest ecosystems can be adequately assessed by correct selection of indicators that represent the achievement of established goals. The discriminant analysis technique on indicators selection consists of separation and classification of new observations on pre-defined groups, reducing the number of variables that are discriminant functions linearly dependent of the original variables. This study aims to define an index composed by structural attributes (number of species and individuals planted, height, basal area, number of regenerant species and individuals and chemical and pedological soil attributes to classify riparian reforested environments regarding to restoration taking as reference reforestation around the the Volta Grande reservoir, Minas Gerais State, Brazil. Eleven variables were used for previous classification of plots in partially restored or unrestored groups and also used for discriminant analysis. Variables selected by the discriminant function generated were: number of species and basal area of planted individuals, number of regenerant species and individuals litter accumulation and soil cation exchange capacity. Compatibility of 98% from previous plot classifications and after index formation, show the representativeness of the selected variables on evaluation of restoration of riparian reforestations.

  18. Methane emissions in Danish riparian wetlands

    DEFF Research Database (Denmark)

    Audet, Joachim; Johansen, Jan Ravn; Andersen, Peter Mejlhede;

    2013-01-01

    The present study was conducted to (i) investigate parameters influencing the fluxes of the greenhouse gas methane (CH4) in Danish riparian wetlands with contrasting vegetation characteristics and (ii) develop models relating CH4 emissions to soil and/or vegetation parameters integrating the...... spatial and temporal variability in the fluxes. Fluxes of CH4 were monitored in 12 wetland plots over a year using static chambers, yielding a dataset with more than 800 measured fluxes of CH4. Yearly emissions of CH4 ranged from −0.2 to 38.3 g CH4-C m−2 year−1, and significant effects of groundwater...... level, soil temperature (10 cm depth), peat depth, sulfate, nitrate, and soil carbon content were found. Two methods based on easily available environmental parameters to estimate yearly CH4 emissions from riparian wetlands are presented. The first uses a generalized linear model (GLM) to predict yearly...

  19. Flow and transport in Riparian Zones

    DEFF Research Database (Denmark)

    Jensen, Jannick Kolbjørn

    flow paths by combining a number of field investigation methods and 2D modeling for the Brynemade site. Field investigations included: (1) hydrogeological characterization using wells, slug and infiltration tests, (2) geophysical imaging of the subsurface using Multi-Electrode-Profiling, (3) and......The PhD study presents research results from two re-established Danish riparian zones, Brynemade and Skallebanke, located along Odense River on the island Funen, Denmark. The overall objectives of the PhD study have been to improve the understanding of flow and transport in riparian zones. The...... methodology focuses on; construction of field sites along Odense River, understanding flow and transport, and performing numerical/analytical model assessments of flow and transport. An initial 2D simulation study was performed with a conceptual setup based on the Brynemade site. Through a series of 2D model...

  20. Biogeochemical processes in forest riparian zones

    OpenAIRE

    Ledesma, José L. J.

    2016-01-01

    The area of interaction between terrestrial and aquatic environments, i.e. the riparian zone (RZ), has long been recognized as an important landscape feature from both scientific and management perspectives. Surface water quality is to a great extent regulated by substances exported from RZs. Boreal forest RZs are characterized by high organic matter content, which drives important biogeochemical processes. The overall objective of this thesis was to develop the understanding of RZ biogeochem...

  1. Mycorrhizas effects on nutrient interception in two riparian grass species

    OpenAIRE

    Hamid Reza Asghari; Timothy Richard Cavagnaro

    2014-01-01

    Effects of arbuscular mycorrhizal (AM) fungi on plant growth and soil nutrient depletion are well known, but their roles as nutrient interceptor in riparian areas are less clear. The effects of AM fungi on growth, soil nutrient depletion and nutrient leaching were investigated in columns with two riparian grass species. Mycorrhizal and non mycorrhizal (NM) plants were grown in a mixture of riparian soil and sand (60% and 40%, w/w respectively) for 8 weeks under glasshouse conditions. Mycorrhi...

  2. Mathematical modeling riparian vegetation zonation in semiarid conditions based on a transpiration index.

    Science.gov (United States)

    Real, Joaquin; Morales, Marco; Garcia, Alicia; Garofano, Virginia; Martinez-Capel, Francisco; Frances, Felix

    2010-05-01

    Initially riparian vegetation modeling was focused on the study of ecological patches without taking into account the interactive effects of structures and processes in between them (Tabacchi et al., 1998). One of the greatest challenges, when carrying out a riparian ecosystem restoration, is to understand the physical and ecological processes of a system and the interaction and feedback within these processes. Jorde (2002) pointed out the importance of addressing complex linkages between processes and biotic interactions in research and in the development of restoration projects over larger spatial and temporal scales in the future. According to Tabacchi et al. (2000), the water cycle in riparian zones depends on three important relations: the water absorption by the plants, water storage and atmospherical return by evaporation. During recent years a variety of ecological models have taken into account the changes in the plant species as consequence of changes in the environmental variables and hydrological alterations (Baptist, 2005; Braatne et al., 2002; Glenz, 2005; Hooke et al., 2005; Murphy et al., 2006). Most of these models are based on functional relationships between river hydrology and vegetation species or communities. In semiarid regions we make the hypothesis transpiration will be one of the key factors determining the riparian vegetation presence and therefore, we will not consider in our model other factors as recruitment, flood damages, etc. The objectives of this work are: firstly to develop a model capable of simulating several riparian vegetation types which can be applied in a wide range of conditions across Mediterranean environments; and secondly to calibrate and to validate the model in several Mediterranean river stretches of the Iberian Peninsula, both in undisturbed and disturbed flow regimes. To achieve these objectives the following methodology has been applied. The model has been conceptualized as a static tank flow model based on the

  3. Riparian buffer zones as pesticide filters of no-till crops.

    Science.gov (United States)

    Aguiar, Terencio R; Bortolozo, F R; Hansel, F A; Rasera, K; Ferreira, M T

    2015-07-01

    Several studies have pointed to the potential benefits of riparian vegetation as buffer zones for agricultural and industrial pollutants harmful to aquatic ecosystems. However, other studies have called into question its use as an ecological filter, questioning the widths and conditions for which they are effective as a filter. In this work, we have investigated the buffering capacity of the riparian one to retain pesticides in the water-saturated zone, on 27 sites composed by riparian buffer zones with different vegetation structure (woody, shrubs, or grass vegetation) and width (12, 36, and 60 m). Five pesticides were analyzed. The effectiveness of the filtering was largely influenced by the width and vegetation type of the buffer zone. In general, decreasing pesticide removal followed in this order wood > shrubs > grass. The 60 m woody buffer zone was the most effective in the removal of all the pesticides. Only atrazine was detected in this case (0.3 μg L(-1)). Furthermore, a linear correlation (R (2) > 0.97) was observed in their removal for all compounds and buffer zones studied. Thus, preserving the woody vegetation in the riparian zone is important for watershed management and groundwater quality in the no-tillage system in temperate climate. PMID:25744820

  4. Herbicide occurrence in riparian soils and its transporting risk in the Songhua River Basin, China

    OpenAIRE

    Sun, Xiaoyin; Zhou, Qixing; Ren, Wenjie

    2013-01-01

    A riparian zone is the interface between land and a river or stream. Riparian zones are major elements of ecosystems. However, human conversion of riparian land to agricultural uses has reduced the ecological benefits of riparian land such as water and pollutant filtration. Over 80 % of the original riparian area has been lost from North America and Europe over the past 200 years. Intensive land use along riparian areas has increased soil erosion and, in turn, sedimentation in rivers. Intensi...

  5. An Ecohydrological Approach to Riparian Restoration Planning in the American Southwest

    Science.gov (United States)

    Leverich, G. T.; Orr, B.; Diggory, Z.; Dudley, T.; Hatten, J.; Hultine, K. R.; Johnson, M. P.; Orr, D.

    2014-12-01

    Riparian systems across the American southwest region are under threat from a growing and intertwined cast of natural and anthropogenic stressors, including flooding, drought, invasion by non-native plants, wildfire, urban encroachment, and land- and water-use practices. In relatively remote and unregulated systems like the upper Gila River in Arizona, riparian habitat value has persisted reasonably well despite much of it being densely infested with non-native tamarisk (salt cedar). A new concern in the watershed, however, is the eventual arrival of the tamarisk leaf beetle that is expected to soon colonize the tamarisk-infested riparian corridor as the beetle continues to spread across the southwest region. While there are numerous potential benefits to tamarisk suppression (e.g., groundwater conservation, riparian habitat recovery, fire-risk reduction), short-term negative consequences are also possible, such as altered channel hydraulics and canopy defoliation during bird nesting season (e.g., the endangered southwestern willow flycatcher). In preparation for anticipated impacts following beetle colonization, we developed a holistic restoration framework to promote recovery of native riparian habitat and subsequent local increases in avian population. Pivotal to this process was an ecohydrological assessment that identified sustainable restoration sites based on consideration of natural and anthropogenic factors that, together, influence restoration opportunities—flood-scour dynamics, vegetation community structure and resilience, surface- and groundwater availability, soil texture and salinity, wildfire potential, and land-use activities. Data collected included high-resolution remote-sensing products, GIS-based delineation of geomorphic activity, and vegetation field mapping. These data along with other information generated, including pre-biocontrol vegetation monitoring and flycatcher-habitat modeling, were synthesized to produce a comprehensive

  6. Mapping preferential flow pathways in a riparian wetland using ground-penetrating radar

    Science.gov (United States)

    Gormally, Kevin Hill

    Preferential flow of water through channels in the soil has been implicated as a vehicle for groundwater and surface water contamination in forested riparian wetland buffers. Water conducted through these by-pass channels can circumvent interaction with wetland biota, biomass, and soils, thereby reducing the buffering capacity of the riparian strips for adsorption and uptake of excess nutrient loads from neighboring agricultural fields and urbanized lands. Models of riparian function need to account for preferential flow to accurately estimate nutrient flux to stream channels, but there are currently no methods for determining the form and prevalence of these pathways outside of extensive destructive sampling. This research developed, tested, and validated a new application of non-invasive ground-penetrating radar technology (GPR) for mapping the three-dimensional structure of near-surface (0-1 m) lateral preferential flow channels. Manual and automated detection methodologies were created for analyzing GPR scan data to locate the channels in the subsurface. The accuracy of the methodologies was assessed in two field test plots with buried PVC pipes simulating the riparian channels. The manual methodology had a 0% Type I error rate and 8% Type II error rate; the automated version had a validated by transmission of tracer dye through the study site and ground truth generated from soil core samples (92% accurate). These GPR tools will enable researchers to efficiently and effectively characterize lateral preferential flow without negatively impacting environmentally sensitive wetland areas. Scientists can now directly study these flow mechanisms to investigate the effects of by-pass pathways on nutrient fate in riparian buffers and the interactions of preferential flow with plant and animal systems.

  7. Riparian vegetation and water yield: A synthesis

    Science.gov (United States)

    Salemi, Luiz Felippe; Groppo, Juliano Daniel; Trevisan, Rodrigo; Marcos de Moraes, Jorge; de Paula Lima, Walter; Martinelli, Luiz Antonio

    2012-08-01

    SummaryForested riparian zones perform numerous ecosystem functions, including the following: storing and fixing carbon; serving as wildlife habitats and ecological corridors; stabilizing streambanks; providing shade, organic matter, and food for streams and their biota; retaining sediments and filtering chemicals applied on cultivated/agricultural sites on upslope regions of the catchments. In this paper, we report a synthesis of a different feature of this type of vegetation, which is its effect on water yield. By synthesizing results from studies that used (i) the nested catchment and (ii) the paired catchment approaches, we show that riparian forests decrease water yield on a daily to annual basis. In terms of the treated area increases on average were 1.32 ± 0.85 mm day-1 and 483 ± 309 mm yr-1, respectively; n = 9. Similarly, riparian forest plantation or regeneration promoted reduced water yield (on average 1.25 ± 0.34 mm day-1 and 456 ± 125 mm yr-1 on daily and annual basis, respectively, when prorated to the catchment area subjected to treatment; n = 5). Although there are substantially fewer paired catchment studies assessing the effect of this vegetation type compared to classical paired catchment studies that manipulate the entire vegetation of small catchments, our results indicate the same trend. Despite the occurrence of many current restoration programs, measurements of the effect on water yield under natural forest restoration conditions are still lacking. We hope that presenting these gaps will encourage the scientific community to enhance the number of observations in these situations as well as produce more data from tropical regions.

  8. NITROUS OXIDE EMISSIONS FROM RIPARIAN BUFFERS AND TREATMENT WETLANDS

    Science.gov (United States)

    Riparian buffers and treatment wetlands are used throughout the world for the protection of water bodies from nonpoint source pollution, particularly nitrogen. Yet, relatively few studies of riparian or treatment wetland denitrification consider the production of nitrous oxide. Nitrous oxide emissio...

  9. Patterns of sediment and phosphorus accumulation in a riparian buffer

    Science.gov (United States)

    Riparian buffers prevent sediment and phosphorus (P) from reaching streams, but their accumulation in buffers is seldom measured. This study's objectives were to determine accumulations of sediment and P in a multi-species riparian buffer, and characterize spatial-temporal patterns of P in soil wate...

  10. Salmon nutrients are associated with the phylogenetic dispersion of riparian flowering-plant assemblages.

    Science.gov (United States)

    Hurteau, Leslie A; Mooers, Arne Ø; Reynolds, John D; Hocking, Morgan D

    2016-02-01

    A signature of nonrandom phylogenetic community structure has been interpreted as indicating community assembly processes. Significant clustering within the phylogenetic structure of a community can be caused by habitat filtering due to low nutrient availability. Nutrient limitation in temperate Pacific coastal rainforests can be alleviated to some extent by marine nutrient subsidies introduced by migrating salmon, which leave a quantitative signature on the makeup of plant communities near spawning streams. Thus, nutrient-mediated habitat filtering could be reduced by salmon nutrients. Here, we ask how salmon abundance affects the phylogenetic structure of riparian flowering plant assemblages across 50 watersheds in the Great Bear Rainforest of British Columbia, Canada. Based on a regional pool of 60 plant species, we found that assemblages become more phylogenetically dispersed and species poor adjacent to streams with higher salmon spawning density. In contrast, increased phylogenetic clumping and species richness was seen in sites with low salmon density, with steeper slopes, further from the stream edge, and within smaller watersheds. These observations are all consistent with abiotic habitat filtering and biotic competitive exclusion acting together across local and landscape-scale gradients in nutrient availability to structure assembly of riparian flowering plants. In this case, rich salmon nutrients appear to release riparian flowering-plant assemblages from the confines of a low-nutrient habitat filter that drives phylogenetic clustering. PMID:27145619

  11. Urbanization and nutrient retention in freshwater riparian wetlands

    Science.gov (United States)

    Hogan, D.M.; Walbridge, M.R.

    2007-01-01

    Urbanization can degrade water quality and alter watershed hydrology, with profound effects on the structure and function of both riparian wetlands (RWs) and aquatic ecosystems downstream. We used freshwater RWs in Fairfax County, Virginia, USA, as a model system to examine: (1) the effects of increasing urbanization (indexed by the percentage of impervious surface cover [%ISC] in the surrounding watershed) on nitrogen (N) and phosphorus (P) concentrations in surface soils and plant tissues, soil P saturation, and soil iron (Fe) chemistry; and (2) relationships between RW soil and plant nutrient chemistries vs. the physical and biotic integrity of adjacent streams. Soil total P and NaOH-extractable P (representing P bound to aluminum [Al] and Fe hydrous oxides) varied significantly but nonlinearly with %ISC (r2 = 0.69 and 0.57, respectively); a similar pattern was found for soil P saturation but not for soil total N. Relationships were best described by second-order polynomial equations. Riparian wetlands appear to receive greater P loads in moderately (8.6-13.3% ISC) than in highly (25.1-29.1% ISC) urbanized watersheds. These observations are consistent with alterations in watershed hydrology that occur with increasing urbanization, directing water and nutrient flows away from natural RWs. Significant increases in total and crystalline soil Fe (r 2 = 0.57 and 0.53, respectively) and decreases in relative soil Fe crystallinity with increasing %ISC suggest the mobilization and deposition of terrestrial sediments in RWs, likely due to construction activities in the surrounding watershed. Increases in RW plant tissue nutrient concentrations and %ISC in the surrounding watershed were negatively correlated with standard indices of the physical and biotic integrity of adjacent streams. In combination, these data suggest that nutrient and sediment inputs associated with urbanization and storm-water management are important variables that affect wetland ecosystem services

  12. Testing the Effects of an Introduced Palm on a Riparian Invertebrate Community in Southern California

    OpenAIRE

    Theresa Sinicrope Talley; Kim-Chi Nguyen; Anthony Nguyen

    2012-01-01

    Despite the iconic association of palms with semi-arid regions, most are introduced and can invade natural areas. Along the San Diego River (San Diego, California, USA), the introduced Canary Island date palm (Phoenix canariensis) forms dense patches among native riparian shrubs like arroyo willow (Salix lasiolepis). The structural differences between the palm and native shrubs are visually obvious, but little is known about palm's effects on the ecosystem. We tested for the effects of the pa...

  13. Nitrate removal in a restored riparian groundwater system: functioning and importance of individual riparian zones

    Directory of Open Access Journals (Sweden)

    S. Peter

    2012-11-01

    Full Text Available For the design and the assessment of river restoration projects, it is important to know to what extent the elimination of reactive nitrogen (N can be improved in the riparian groundwater. We investigated the effectiveness of different riparian zones, characterized by a riparian vegetation succession, for nitrate (NO3 removal from infiltrating river water in a restored and a still channelized section of the river Thur, Switzerland. Functional genes of denitrification (nirS and nosZ were relatively abundant in groundwater from willow bush and mixed forest dominated zones, where oxygen concentrations remained low compared to the main channel and other riparian zones. After flood events, a substantial decline in NO3 concentration (> 50% was observed in the willow bush zone but not in the other riparian zones closer to the river. In addition, the characteristic enrichment of 15N and 18O in the residual NO3 pool (by up to 22‰ for δ15N and up to 12‰ for δ18O provides qualitative evidence that the willow bush and forest zones were sites of active denitrification and, to a lesser extent, NO3 removal by plant uptake. Particularly in the willow bush zone during a period of water table elevation after a flooding event, substantial input of organic carbon into the groundwater occurred, thereby fostering post-flood denitrification activity that reduced NO3 concentration with a rate of ~21 μmol N l−1 d−1. Nitrogen removal in the forest zone was not sensitive to flood pulses, and overall NO3 removal rates were lower (~6 μmol l−1 d−1. Hence, discharge-modulated vegetation–soil–groundwater coupling was found to be a key driver for riparian NO3 removal. We estimated that

  14. RFV Index for the evaluation of the ecological status of riparian forests; Indice RFV para la valoracion del estado del bosque de ribera

    Energy Technology Data Exchange (ETDEWEB)

    Magdaleno, F.; Martinez, R.; Roch, V.

    2010-07-01

    This paper presents an index (RFV-Riparian Forest Evaluation) for the assessment of the ecological condition of the riparian forest in perennial rivers. The development of the Directive 2000/60/EC requires the utilization of methods for the assessment of the hydromorphological quality of the natural channels. Among others, it includes the condition of the riparian forest as one of the fundamental components in the determination of the structure of the riverine areas. The RFV index is presented with that aim, and also to improve the existing methodologies for the valorisation of the riparian forests. Its calculation is based on the assessment of the spatial continuity of the forest (in its three core dimensions-longitudinal, transversal and vertical) and the temporal continuity of the forest, represented by its natural regeneration, as a guarantee of its future continuity. This index makes possible the valorisation of the quality and degree of alteration of the riparian forest. Besides, it helps to determine the management scenarios that are necessary to improve the status of the riparian forest, and to develop processes of restoration of its structure and composition. (Author)

  15. Stereophotogrammetry in studies of riparian vegetation dynamics

    Science.gov (United States)

    Hortobagyi, Borbala; Vautier, Franck; Corenblit, Dov; Steiger, Johannes

    2014-05-01

    Riparian vegetation responds to hydrogeomorphic disturbances and also controls sediment deposition and erosion. Spatio-temporal riparian vegetation dynamics within fluvial corridors have been quantified in many studies using aerial photographs and GIS. However, this approach does not allow the consideration of woody vegetation growth rates (i.e. vertical dimension) which are fundamental when studying feedbacks between the processes of fluvial landform construction and vegetation establishment and succession. We built 3D photogrammetric models of vegetation height based on aerial argentic and digital photographs from sites of the Allier and Garonne Rivers (France). The models were realized at two different spatial scales and with two different methods. The "large" scale corresponds to the reach of the river corridor on the Allier river (photograph taken in 2009) and the "small" scale to river bars of the Allier (photographs taken in 2002, 2009) and Garonne Rivers (photographs taken in 2000, 2002, 2006 and 2010). At the corridor scale, we generated vegetation height models using an automatic procedure. This method is fast but can only be used with digital photographs. At the bar scale, we constructed the models manually using a 3D visualization on the screen. This technique showed good results for digital and also argentic photographs but is very time-consuming. A diachronic study was performed in order to investigate vegetation succession by distinguishing three different classes according to the vegetation height: herbs (trees (>4 m). Both methods, i.e. automatic and manual, were employed to study the evolution of the three vegetation classes and the recruitment of new vegetation patches. A comparison was conducted between the vegetation height given by models (automatic and manual) and the vegetation height measured in the field. The manually produced models (small scale) were of a precision of 0.5-1 m, allowing the quantification of woody vegetation growth rates

  16. Climate change effects on lowland stream flood regimes and riparian rich fen vegetation communities in Denmark

    DEFF Research Database (Denmark)

    Thodsen, Hans; Baattrup-Pedersen, Annette; Andersen, Hans Estrup;

    2016-01-01

    There is growing awareness that an intensification of the hydrological cycle associated with climate change in many parts of the world will have profound implications for river ecosystem structure and functions. In the present study we link an ensemble of regional climate model projections...... to a hydrological model with the aim to predict climate driven changes in flooding regimes in lowland riparian areas. Our specific aims were to 1) predict effects of climate change on flood frequencies and magnitudes in riparian areas by using an ensemble of six climate models and 2) combine the obtained...... predictions with the distribution of rich fen communities to explore whether these are likely to be subjected to increased flooding by a climate change induced increase in river runoff. We found that all regional climate models in the ensemble showed increases in mean annual runoff and that the increase...

  17. Riparian invasive alters stream nitrogen dynamics.

    Science.gov (United States)

    Mineau, M.; Baxter, C.; Marcarelli, A.; Minshall, G.

    2008-12-01

    Invasive species may be most likely to have strong effects on the ecosystem they invade when they contribute a new function such as nitrogen (N) fixation. Russian olive (Eleagnus angustifolia) is a non-native invasive tree which is rapidly spreading along riparian corridors in the American West. Russian olive is a nitrogen fixing plant due to a symbiotic relationship with Actinomycetes and is invading systems that frequently lack a strong native N fixer. The contribution of reactive N by these invasive riparian plants to soils may also be altering N cycling and processing in the adjacent streams. We measured nutrient limitation via periphyton growth on nutrient diffusing substrates and nitrate uptake using short term nitrate additions in Deep Creek, ID. Measurements were made in three reaches along a Russian olive invasion gradient, with an upstream reference reach that has no Russian olive and two downstream invaded reaches, one with moderate density and one with high density. Periphyton growth in Deep Creek was significantly N limited in the reference reach while the moderately invaded reach showed no significant limitation and the highly invaded reach was significantly P limited. The nitrate uptake velocity (Vf) for both of the invaded reaches was an order of magnitude less than the reference reach, implying that biological demand for nitrate is significantly less in the invaded reaches than the reference. Considering the current extent of Russian olive invasion and its continued rapid spread, possible alteration of N cycling in waterways may have important implications for the management of both this invasive species and management of nutrient pollution in waters of the western U.S.

  18. Improved Mapping of Riparian Wetlands Using Reach Topography (ECOSERV)

    Science.gov (United States)

    Riparian wetlands provide a suite of ecosystems services including floodwater retention, biogeochemical processing, and habitat provisioning. However in one mid-Atlantic watershed the National Wetlands Inventory was shown to underrepresent these systems by greater than 50%. These...

  19. Improved Mapping of Riparian Wetlands Using Reach Topography

    Science.gov (United States)

    Riparian wetlands provide a suite of ecosystems services including floodwater retention, biogeochemical processing, and habitat provisioning. However in one mid-Atlantic watershed the National Wetlands Inventory was shown to underrepresent these systems by greater than 50%. These...

  20. Responses of riparian guilds to flowalterations in a Mediterranean stream

    OpenAIRE

    Bejarano Carrión, María Dolores; Gonzalez del Tanago del Rio, Marta; García de Jalón Lastra, Diego; Marchamalo Sacristán, Miguel; Sordo Ward, Alvaro; Solana Gutierrez, Joaquin

    2012-01-01

    Questions: Do Mediterranean riparian guilds show distinct responses to stream water declines? If observed,which are the most sensitive and resilient guilds and theirmost affected attributes? Location: Tie¿tar river below the Rosarito dam, central-western Spain. Methods: We identified riparian guilds based on key woody species features and species distribution within this Mediterranean river corridor, and evaluated similarity of their responses to long-term flow alteration (i.e. stream water d...

  1. Riparian zone controls on base cation concentrations in boreal streams

    Directory of Open Access Journals (Sweden)

    J. L. J. Ledesma

    2013-01-01

    Full Text Available Forest riparian zones are a major in control of surface water quality. Base cation (BC concentrations, fluxes, and cycling in the riparian zone merit attention because of increasing concern of negative consequences for re-acidification of surface waters from future climate and forest harvesting scenarios. We present a two-year study of BC and silica (Si flow-weighted concentrations from 13 riparian zones and 14 streams in a boreal catchment in northern Sweden. The Riparian Flow-Concentration Integration Model (RIM was used to estimate riparian zone flow-weighted concentrations and tested to predict the stream flow-weighted concentrations. Spatial variation in BC and Si concentrations as well as in flow-weighted concentrations was related to differences in Quaternary deposits, with the largest contribution from lower lying silty sediments and the lowest contribution from wetland areas higher up in the catchment. Temporal stability in the concentrations of most elements, a remarkably stable Mg / Ca ratio in the soil water and a homogeneous mineralogy suggest that the stable patterns found in the riparian zones are a result of distinct mineralogical upslope groundwater signals integrating the chemical signals of biological and chemical weathering. Stream water Mg / Ca ratio indicates that the signal is subsequently maintained in the streams. RIM gave good predictions of Ca, Mg, and Na flow-weighted concentrations in headwater streams. The difficulty in modelling K and Si suggests a stronger biogeochemical influence on these elements. The observed chemical dilution effect with flow in the streams was related to variation in groundwater levels and element concentration profiles in the riparian zones. This study provides a first step toward specific investigations of the vulnerability of riparian zones to changes induced by forest management or climate change, with focus on BC or other compounds.

  2. Incorporating climate change projections into riparian restoration planning and design

    Science.gov (United States)

    Perry, Laura G.; Lindsay V. Reynolds; Beechie, Timothy J.; Collins, Mathias J.; Shafroth, Patrick B.

    2015-01-01

    Climate change and associated changes in streamflow may alter riparian habitats substantially in coming decades. Riparian restoration provides opportunities to respond proactively to projected climate change effects, increase riparian ecosystem resilience to climate change, and simultaneously address effects of both climate change and other human disturbances. However, climate change may alter which restoration methods are most effective and which restoration goals can be achieved. Incorporating climate change into riparian restoration planning and design is critical to long-term restoration of desired community composition and ecosystem services. In this review, we discuss and provide examples of how climate change might be incorporated into restoration planning at the key stages of assessing the project context, establishing restoration goals and design criteria, evaluating design alternatives, and monitoring restoration outcomes. Restoration planners have access to numerous tools to predict future climate, streamflow, and riparian ecology at restoration sites. Planners can use those predictions to assess which species or ecosystem services will be most vulnerable under future conditions, and which sites will be most suitable for restoration. To accommodate future climate and streamflow change, planners may need to adjust methods for planting, invasive species control, channel and floodplain reconstruction, and water management. Given the considerable uncertainty in future climate and streamflow projections, riparian ecological responses, and effects on restoration outcomes, planners will need to consider multiple potential future scenarios, implement a variety of restoration methods, design projects with flexibility to adjust to future conditions, and plan to respond adaptively to unexpected change.

  3. Riparian Areas of Greece: Their Definition and Characteristics

    Directory of Open Access Journals (Sweden)

    D. Gounaridis

    2010-01-01

    Full Text Available Riparian areas are unique and of high importance ecosystems because they are adjacent to surface freshwater bodies suchas streams, rivers and lakes. They are the semi-aquatic transitional zones (ecotones between terrestrial and aquatic ecosystems.Water, soil and vegetation are the three main characteristics that differentiate them compared to other ecosystems.Furthermore, they are present in all biomes (from deserts to tropical forests and are found in a great range of hydrologic andgeomorphologic conditions that results in a great variety of riparian habitat types. In Greece, there are five major riparianforest habitat types that also occur in most of the semi-arid Mediterranean regions. Frequent disturbance is another uniquecharacteristic that differentiates riparian areas. The major disturbances that shape riparian areas in Greece are unpredictedflood and drought events, as well as fires but to a lesser degree. Wetlands are another important semi-aquatic ecosystemsthat many consider as synonymous to riparian areas. In reality, these two ecosystems overlap but they are also different sincewetlands are considered as “wetter” and less disturbance driven than riparian areas.

  4. Using continuous surface water level and temperature data to characterize hydrological connectivity in riparian wetlands.

    Science.gov (United States)

    Cabezas, Alvaro; Gonzalez-Sanchís, Maria; Gallardo, Belinda; Comín, Francisco A

    2011-12-01

    Methods to characterize hydrological connectivity at riparian wetlands are necessary for ecosystem management given its importance over ecosystem structure and functioning. In this paper, we aimed to describe hydrological connectivity at one Ebro River reach (NE Spain) and test a method to perform such characterization. Continuous surface water level and temperature data were recorded at five riparian wetlands during the period October 2006-June 2007. Combining water level and temperature, we classified the examined wetlands in three groups, which mainly differed in the dominant water source during different flood stages. Firstly, a comparison of water level fluctuations in riparian wetlands with those in the river channel during events with different characteristics was used to describe hydrological connectivity. Such comparison was also used to extract quantitative hydrological connectivity descriptors as the wetland response initiation time. Secondly, water temperature series were divided in phases with different average, range and daily oscillation, and these parameters were interpreted for each phase to identify dominant flowpaths. By doing so, a more complete description of hydrological connectivity was achieved. Our method provided useful insights to describe hydrological connectivity using a qualitative approach that can be expanded if required to include quantitative parameters for studies of biotic assemblages or ecosystem processes. PMID:21400244

  5. Early response of soil properties and function to riparian rainforest restoration.

    Directory of Open Access Journals (Sweden)

    Rose Gageler

    Full Text Available Reforestation of riparian zones is increasingly practiced in many regions for purposes of biodiversity conservation, bank stabilisation, and improvement in water quality. This is in spite of the actual benefits of reforestation for recovering underlying soil properties and function remaining poorly understood. Here we compare remnant riparian rainforest, pasture and reforestation plantings aged 2-20 years in an Australian subtropical catchment on ferrosols to determine the extent to which reforestation restores key soil properties. Of the nine soil attributes measured (total nitrogen, nitrate and ammonium concentrations, net nitrification and ammonification rates, organic carbon, bulk density, fine root biomass and water infiltration rates, only infiltration rates were significantly lower in pasture than remnant riparian rainforest. Within reforestation plantings, bulk density decreased up to 1.4-fold and infiltration rates increased up to 60-fold with time post-reforestation. Our results suggest that the main outcome of belowground processes of early reforestation is the recovery of the soils' physical structure, with potential beneficial ecosystem services including reduced runoff, erosion and associated sediment and nutrient loads in waterways. We also demonstrate differential impacts of two commonly planted tree species on a subset of soil properties suggesting that preferential planting of select species could accelerate progress on specific restoration objectives.

  6. A comparison of small-mammal communities in a desert riparian floodplain

    Science.gov (United States)

    Ellison, Laura E.; van Riper, Charles, III

    1998-01-01

    We compared small-mammal communities between inactive floodplain and actively flooded terraces of riparian habitat in the Verde Valley of central Arizona. We used species diversity, abundance, weight of adult males, number of juveniles, number of reproductively active individuals, longevity, residency status, and patterns of microhabitat use to compare the two communities. Although abundances of small mammals tended to be higher in the active floodplain, species diversity was greater in the inactive floodplain. Results were inconsistent with our initial prediction that actively flooded riparian habitat acts as a species source, whereas inactive floodplain acts as a sink or dispersal site for small mammals. Within each habitat type, we found evidence of significant microhabitat separation among the three most abundant small-mammal species (Peromyscus boylii, P. eremicus, and Neotoma albigula). Percent cover by annual and perennial grasses and shrubs, substrate, and frequency of shrubs, trees, and debris were significant determinants of small-mammal distribution within a habitat type. We found that the three most abundant species selected a nonrandom subset of available habitat. Nonrandom use of habitat and microhabitat separation were the two most important mechanisms structuring small-mammal communities in riparian habitat of central Arizona.

  7. Cost of riparian buffer zones: A comparison of hydrologically adapted site-specific riparian buffers with traditional fixed widths

    Science.gov (United States)

    Tiwari, T.; Lundström, J.; Kuglerová, L.; Laudon, H.; Öhman, K.; Ågren, A. M.

    2016-02-01

    Traditional approaches aiming at protecting surface waters from the negative impacts of forestry often focus on retaining fixed width buffer zones around waterways. While this method is relatively simple to design and implement, it has been criticized for ignoring the spatial heterogeneity of biogeochemical processes and biodiversity in the riparian zone. Alternatively, a variable width buffer zone adapted to site-specific hydrological conditions has been suggested to improve the protection of biogeochemical and ecological functions of the riparian zone. However, little is known about the monetary value of maintaining hydrologically adapted buffer zones compared to the traditionally used fixed width ones. In this study, we created a hydrologically adapted buffer zone by identifying wet areas and groundwater discharge hotspots in the riparian zone. The opportunity cost of the hydrologically adapted riparian buffer zones was then compared to that of the fixed width zones in a meso-scale boreal catchment to determine the most economical option of designing riparian buffers. The results show that hydrologically adapted buffer zones were cheaper per hectare than the fixed width ones when comparing the total cost. This was because the hydrologically adapted buffers included more wetlands and low productive forest areas than the fixed widths. As such, the hydrologically adapted buffer zones allows more effective protection of the parts of the riparian zones that are ecologically and biogeochemically important and more sensitive to disturbances without forest landowners incurring any additional cost than fixed width buffers.

  8. The chemical composition and source identification of soil dissolved organic matter in riparian buffer zones from Chongming Island, China.

    Science.gov (United States)

    Wang, Yulai; Yang, Changming; Li, Jianhua; Shen, Shuo

    2014-09-01

    Dissolved organic matter (DOM) that is derived from the soil of riparian buffer zones has a complex chemical composition, and it plays an important role in the transport and transformation of pollutants. To identify the source of DOM and to better understand its chemical and structural properties, we collected 33 soil samples from zones with fluctuating water levels along the major rivers on Chongming Island, evaluated the DOM contents in riparian soil, analyzed the chemical composition and functional groups and traced DOM origins by using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS) combined with clustering analysis. All sampling sites were divided into four groups by principal component analysis (PCA) on the basis of the DOM molecules. The results showed that there was no significant difference in the DOM contents between every two groups; however, the DOM fractions differed significantly among the different site groups in the following order: Σ lipids and Σ proteins>Σ sugars and Σ fatty acids>Σ amino acids, Σ indoles and Σ alkaloids. DOM in the riparian buffer zones originated from riparian plants, domestic sewage and agricultural activities, and the hydrophobic and amphiphilic fractions accounting for over 60% of the identified molecules were the dominant fractions. Our study has confirmed the heterogeneous properties of DOM, and it is of vital importance to isolate and characterize the various DOM fractions at the molecular level for a better understanding of the behavior and roles of DOM in the natural environment. PMID:24997959

  9. Beyond the Transboundary River: Issues of Riparian Responsibilities

    Science.gov (United States)

    Parhi, P. K.; Sankhua, R. N.

    2013-11-01

    The issues of riparian countries sharing transboundary waters spans decades, and has been greatly strengthened by its collaboration with partner agencies. International cooperation on shared water resources is critical, especially in water scarce regions experiencing the impacts of over-consumption and pollution. Where, river basins are transboundary, this requires regular and structured consultation, coordination and cooperation among all states sharing the catchment. Rapid and unsustainable development of river basins and their wetlands has led to the disruption of natural hydrological cycles. In many cases this has resulted in greater frequency and severity of flooding, drought and pollution. Appropriate transnational planning, protection and allocation of water to wetlands are essential to avoid disaster and enable these ecosystems to continue to provide important goods and services to local communities. Integrated river basin management takes into account policies and measures for the multifunctional use of rivers on a catchment scale and associated institutional changes. The implementation of these involves a number of steps such as definition of aim, construction of conceptual model, selection of variables, comparison with selection criteria, database assessment, and indicator selection division of tasks and responsibilities for river basin management with regard to the development of indicators, data collection, and their application in decision-making. This work presents issues pertaining to the pressure to the river, the state of the river ecosystem, the impact to goods and services provided by the river, and the societal response.

  10. The effects of flooding disturbance on the distribution and behaviour of riparian arthropods along a lowland gravel river

    OpenAIRE

    Lambeets, Kevin

    2009-01-01

    This Ph.D.-thesis aimed to address which environmental factors influence the assemblage structure of mobile, riparian arthropods along spatially structured river banks of a rain-fed, lowland gravel river, the Common Meuse. As riverine ecosystems are basically non-equilibrium, dynamic ecosystems, mainly flow regimes and flood pulse characteristics are expected to shape both the distribution and behaviour of its inhabitants. The river banks along the Common Meuse are (in)frequently disturbed by...

  11. Classification of riparian forest species and health condition using multi-temporal and hyperspatial imagery from unmanned aerial system.

    Science.gov (United States)

    Michez, Adrien; Piégay, Hervé; Lisein, Jonathan; Claessens, Hugues; Lejeune, Philippe

    2016-03-01

    Riparian forests are critically endangered many anthropogenic pressures and natural hazards. The importance of riparian zones has been acknowledged by European Directives, involving multi-scale monitoring. The use of this very-high-resolution and hyperspatial imagery in a multi-temporal approach is an emerging topic. The trend is reinforced by the recent and rapid growth of the use of the unmanned aerial system (UAS), which has prompted the development of innovative methodology. Our study proposes a methodological framework to explore how a set of multi-temporal images acquired during a vegetative period can differentiate some of the deciduous riparian forest species and their health conditions. More specifically, the developed approach intends to identify, through a process of variable selection, which variables derived from UAS imagery and which scale of image analysis are the most relevant to our objectives.The methodological framework is applied to two study sites to describe the riparian forest through two fundamental characteristics: the species composition and the health condition. These characteristics were selected not only because of their use as proxies for the riparian zone ecological integrity but also because of their use for river management.The comparison of various scales of image analysis identified the smallest object-based image analysis (OBIA) objects (ca. 1 m(2)) as the most relevant scale. Variables derived from spectral information (bands ratios) were identified as the most appropriate, followed by variables related to the vertical structure of the forest. Classification results show good overall accuracies for the species composition of the riparian forest (five classes, 79.5 and 84.1% for site 1 and site 2). The classification scenario regarding the health condition of the black alders of the site 1 performed the best (90.6%).The quality of the classification models developed with a UAS-based, cost-effective, and semi-automatic approach

  12. 2006 Progress report: Riparian willow restoration along the Illinois river at Arapahoe NWR, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a progress report concerning riparian willow restoration on Arapahoe NWR. Riparian willow communities along the Illinois River at Arapaho NWR provide...

  13. 2005 Progress report: Riparian willow restoration along the Illinois river at Arapahoe NWR, Colorado

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a progress report concerning riparian willow restoration on Arapahoe NWR. Riparian willow communities along the Illinois River at Arapaho NWR provide...

  14. The Soil Bacterial Communities of South African Fynbos Riparian Ecosystems Invaded by Australian Acacia Species

    OpenAIRE

    Slabbert, Etienne; Jacobs, Shayne Martin; Jacobs, Karin

    2014-01-01

    Riparian ecosystem along rivers and streams are characterised by lateral and longitudinal ecological gradients and, as a result, harbour unique biodiversity. Riparian ecosystems in the fynbos of the Western Cape, South Africa, are characterised by seasonal dynamics, with summer droughts followed by high flows during winter. The unique hydrology and geomorphology of riparian ecosystems play an important role in shaping these ecosystems. The riparian vegetation in the Western Cape has, however,...

  15. Bank Erosion Modulated by Exposed Roots from Riparian Vegetation in Small Gravel-Bed Streams

    Science.gov (United States)

    Mendoza, A.; Frias, C. E.; Langendoen, E. J.; Abad, J. D.

    2013-12-01

    Bank erosion is a process present in rivers of all the scales and is a key aspect in the evolution of meandering streams. Its magnitude is significantly controlled by the resistance-to-erosion properties of the floodplain materials, which themselves are modified by the varying presence of riparian vegetation. Earlier studies have stated that the physical science of fluvial geomorphology was flawed because of omitting such processes, because they are difficult to describe physically or statistically. For example, the role of vegetation dynamics in modulating river migration, especially for small rivers where the effect of vegetation on channel morphology may be a more important component when compared to larger river systems such as the Amazon or Mississippi Rivers, is largely unknown. Though earlier studies have researched various aspects concerning the effects of riparian vegetation on bank erosion mechanics, a comprehensive framework that integrates and quantifies fluvial erosion and bank failure processes, near-bank hydrodynamics, soil properties and riparian vegetation characteristics is lacking. The effects of exposed roots and rootwads on the near-bank hydrodynamics and sediment transport processes are still not well understood. Laboratory studies have examined in detail the impact of vegetation located only on the bank toe or stream bed. Moreover, there exist no data that explicitly relates the characteristics of riparian vegetation on the bank top to changes in near-bank hydrodynamics and bank erosion mechanics. Further, there is a need to better understand the processes and their interactions occurring at the different spatial scales: single large root, rootwad, and reach. During 2011, 2012 a field campaign was carried out to study the effects of exposed root systems on flow in Fonner Run and Bates Fork, two tributaries of Tenmile Creek (Green and Washington Counties, Pennsylvania). Data collected consist of annual bathymetry, field velocity profiles

  16. RIPARIAN MONITORING USING 2-CM GSD AERIAL PHOTOGRAPHY

    Science.gov (United States)

    Riparian monitoring is a key aspect of sustainable resource management and is mandated by US federal law for federal land-management agencies. However, it is an endeavor hampered by rising manpower costs and time-consuming travel and methods. These limitations tend to reduce sampling intensity per r...

  17. Riparian vegetation: degradation, alien plant invasions, and restoration prospects

    Czech Academy of Sciences Publication Activity Database

    Richardson, D. M.; Holmes, P. M.; Esler, K. J.; Galatowitsch, S. M.; Stromberg, J. C.; Kirkman, S. P.; Pyšek, Petr; Hobbs, R. J.

    2007-01-01

    Roč. 13, č. 1 (2007), s. 126-139. ISSN 1366-9516 Institutional research plan: CEZ:AV0Z60050516 Keywords : riparian habitats * plant invasions * biogeography Subject RIV: EF - Botanics Impact factor: 2.965, year: 2007

  18. Aquatic subsidies transport anthropogenic nitrogen to riparian spiders

    International Nuclear Information System (INIS)

    Stable nitrogen isotopic composition (δ15N) of aquatic biota increases with anthropogenic N inputs such as sewage and livestock waste downstream. Increase in δ15N of riparian spiders downstream may reflect the anthropogenic pollution exposure through predation on aquatic insects. A two-source mixing model based on stable carbon isotopic composition showed the greatest dependence on aquatic insects (84%) by horizontal web-building spiders, followed by intermediate (48%) and low (31%) dependence by cursorial and vertical web-building spiders, respectively. The spider body size was negatively correlated with the dietary proportion of aquatic insects and spider δ15N. The aquatic subsidies transported anthropogenic N to smaller riparian spiders downstream. This transport of anthropogenic N was regulated by spider's guild designation and body size. - Highlights: → δ15N of aquatic insects increases downstream with anthropogenic nitrogen inputs. → δ15N of riparian spiders increases with a high dietary proportion of aquatic insects and smaller spider body size. → The aquatic subsidies transport anthropogenic nitrogen to smaller riparian spiders downstream. - Smaller spiders assimilate anthropogenic nitrogen through the predation on aquatic subsides.

  19. Featured collection introduction: riparian ecosystems and buffers II

    Science.gov (United States)

    Riparian ecosystems, the interface of terrestrial and aquatic systems, are zones of high biodiversity (Naiman et al., 1993), rapid biogeochemical activity (Vidon et al., 2010), complex hydrologic activity (Mayer et al., 2010a), and offer solace that can bestow significant mental ...

  20. Monitoring vegetation water uptake in a semiarid riparian corridor

    Science.gov (United States)

    Robinson, J.; Ochoa, C. G.; Leonard, J.

    2015-12-01

    With a changing global climate and growing demand for water throughout the world, responsible and sustainable land and water resource management practices are becoming increasingly important. Accounting for the amount of water used by riparian vegetation is a critical element for better managing water resources in arid and semiarid environments. The objective of this study was to determine water uptake by selected riparian vegetative species in a semiarid riparian corridor in North-Central Oregon. Exo-skin sap flow sensors (Dynamax, Houston, TX, U.S.A.) were used to measure sap flux in red alder (Alnus rubra) trees, the dominant overstory vegetation at the field site. Xylem sap flow data was collected from selected trees at the field site and in a greenhouse setting. Transpiration rates were determined based on an energy balance method, which makes it possible to estimate the mass flow of sap by measuring the velocity of electrical heat pulses through the plant stem. Preliminary field results indicate that red alder tree branches of about 1 inch diameter transpire between 2 and 6 kg of water/day. Higher transpiration rates of up to 7.3 kg of water/day were observed under greenhouse conditions. Streamflow and stream water temperature, vegetation characteristics, and meteorological data were analyzed in conjunction with transpiration data. Results of this study provide insight on riparian vegetation water consumption in water scarce ecosystems. This study is part of an overarching project focused on climate-vegetation interactions and ecohydrologic processes in arid and semiarid landscapes.

  1. Status of riparian ecosystems in the United States

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An attempt was made to review all available data on the extent and status of riparian ecosystems in the U.S.A. This report presents a synthesis of the findings,...

  2. Riparian Sediment Delivery Ratio: Stiff Diagrams and Artifical Neural Networks

    Science.gov (United States)

    Various methods are used to estimate sediment transport through riparian buffers and grass jilters with the sediment delivery ratio having been the most widely applied. The U.S. Forest Service developed a sediment delivery ratio using the stiff diagram and a logistic curve to int...

  3. Development and Evaluation of a Riparian Buffer Mapping Tool

    Science.gov (United States)

    Milheim, Lesley E.; Claggett, Peter R.

    2008-01-01

    Land use and land cover within riparian areas greatly affect the conditions of adjacent water features. In particular, riparian forests provide many environmental benefits, including nutrient uptake, bank stabilization, steam shading, sediment trapping, aquatic and terrestrial habitat, and stream organic matter. In contrast, residential and commercial development and associated transportation infrastructure increase pollutant and nutrient loading and change the hydrologic characteristics of the landscape, thereby affecting both water quality and habitat. Restoring riparian areas is a popular and cost effective restoration technique to improve and protect water quality. Recognizing this, the Chesapeake Executive Council committed to restoring 10,000 miles of riparian forest buffers throughout the Chesapeake Bay watershed by the year 2010. In 2006, the Chesapeake Executive Council further committed to 'using the best available...tools to identify areas where retention and expansion of forests is most needed to protect water quality'. The Chesapeake Bay watershed encompasses 64,000 square miles, including portions of six States and Washington, D.C. Therefore, the interpretation of remotely sensed imagery provides the only effective technique for comprehensively evaluating riparian forest protection and restoration opportunities throughout the watershed. Although 30-meter-resolution land use and land cover data have proved useful on a regional scale, they have not been equally successful at providing the detail required for local-scale assessment of riparian area characteristics. Use of high-resolution imagery (HRI) provides sufficient detail for local-scale assessments, although at greater cost owing to the cost of the imagery and the skill and time required to process the data. To facilitate the use of HRI for monitoring the extent of riparian forest buffers, the U.S. Forest Service and the U.S. Geological Survey Eastern Geographic Science Center funded the

  4. 2011 Los Alamos National Laboratory Riparian Inventory Results

    Energy Technology Data Exchange (ETDEWEB)

    Norris, Elizabeth J. [Los Alamos National Laboratory; Hansen, Leslie A. [Los Alamos National Laboratory; Hathcock, Charles D. [Los Alamos National Laboratory; Keller, David C. [Los Alamos National Laboratory; Zemlick, Catherine M. [Los Alamos National Laboratory

    2012-03-29

    A total length of 36.7 kilometers of riparian habitat were inventoried within LANL boundaries between 2007 and 2011. The following canyons and lengths of riparian habitat were surveyed and inventoried between 2007 and 2011. Water Canyon (9,669 m), Los Alamos Canyon (7,131 m), Pajarito Canyon (6,009 m), Mortandad Canyon (3,110 m), Two-Mile Canyon (2,680 m), Sandia Canyon (2,181 m), Three-Mile Canyon (1,883 m), Canyon de Valle (1,835 m), Ancho Canyon (1,143 m), Canada del Buey (700 m), Sandia Canyon (221 m), DP Canyon (159 m) and Chaquehui Canyon (50 m). Effluent Canyon, Fence Canyon and Potrillo Canyon were surveyed but no areas of riparian habitat were found. Stretches of inventoried riparian habitat were classified for prioritization of treatment, if any was recommended. High priority sites included stretches of Mortandad Canyon, LA Canyon, Pajarito Canyon, Two-Mile Canyon, Sandia Canyon and Water Canyon. Recommended treatment for high priority sites includes placement of objects into the stream channel to encourage sediment deposition, elimination of channel incision, and to expand and slow water flow across the floodplain. Additional stretches were classified as lower priority, and, for other sites it was recommended that feral cattle and exotic plants be removed to aid in riparian habitat recovery. In June 2011 the Las Conchas Wildfire burned over 150,000 acres of land in the Jemez Mountains and surrounding areas. The watersheds above LA Canyon, Water Canyon and Pajarito Canyon were burned in the Las Conchas Wildfire and flooding and habitat alteration were observed in these canyon bottoms (Wright 2011). Post fire status of lower priority areas may change to higher priority for some of the sites surveyed prior to the Las Conchas Wildfire, due to changes in vegetation cover in the adjacent upland watershed.

  5. Susceptibility of riparian wetland plants to perfluorooctanoic acid (PFOA) accumulation.

    Science.gov (United States)

    Mudumbi, J B N; Ntwampe, S K O; Muganza, M; Okonkwo, J O

    2014-01-01

    As plants have been shown to accumulate organic compounds from contaminated sediments, there is a potential for long-lasting ecological impact as a result of contaminant accumulation in riparian areas of wetlands, particularly the accumulation of non-biodegradable contaminants such as perfluorooctanoic acid (PFOA). In this study, commonly found riparian wetland plants including reeds, i.e., Xanthium strumarium, Phragmites australis, Schoenoplectus corymbosus, Ruppia maritime; Populus canescens, Polygonum salicifolium, Cyperus congestus; Persicaria amphibian, Ficus carica, Artemisia schmidtiana, Eichhornia crassipes, were studied to determine their susceptibility to PFOA accumulation from PFOA contaminated riparian sediment with a known PFOA concentration, using liquid chromatography/tandem mass spectrometry (LC/MS/MS). The bioconcentration factor (BCF) indicated that the plants affinity to PFOA accumulation was; E. crassipes, > P. sali-cifolium, > C. congestus, > P. x canescens, > P. amphibian, > F. carica, > A. schmidtiana, > X. strumarium,> P. australis, > R. maritime, > S. corymbosus. The concentration of PFOA in the plants and/or reeds was in the range 11.7 to 38 ng/g, with a BCF range of 0.05 to 0.37. The highest BCF was observed in sediment for which its core water had a high salinity, total organic carbon and a pH which was near neutral. As the studied plants had a higher affinity for PFOA, the resultant effect is that riparian plants such as E. crassipes, X. strumarium, and P. salicifolium, typified by a fibrous rooting system, which grow closer to the water edge, exacerbate the accumulation of PFOA in riparian wetlands. PMID:24933893

  6. Agrobiodiversity in riparian backyards and rural cutover lands in the Boca do Moa community – Acre, Brazil

    Directory of Open Access Journals (Sweden)

    Williane Maria de Oliveira Martins

    2012-09-01

    Full Text Available The riparian rural cutover lands and backyards represent a sustainable alternative for the production of food and medicinal drugs to the traditional communities from the Amazon, especially with regard to products diversity and income generation. Considering the ecological and social functions of these spaces, this paper aims at analyzing the agrobiodiversity of these environments in the Boca Moa community, in the town of Cruzeiro do Sul, Acre, Brazil. Data collection was carried out through participative, formal, and inductive interviews following a semi-structured questionnaire with open questions, besides in loco visits. The rural cutover lands present many species at the same area, and manioc is the main product cultivated. The backyards have spatial arrangements of food species, with emphasis on fruits and vegetables, besides medicinal plants. Thus, both the backyards and rural cutover lands participate in the subsistence and income of riparian families from this community.

  7. Using chemical, hydrologic, and age dating analysis to delineate redox processes and flow paths in the riparian zone of a glacial outwash aquifer-stream system

    Science.gov (United States)

    Puckett, L.J.; Cowdery, T.K.; McMahon, P.B.; Tornes, L.H.; Stoner, J.D.

    2002-01-01

    A combination of chemical and dissolved gas analyses, chlorofluorocarbon age dating, and hydrologic measurements were used to determine the degree to which biogeochemical processes in a riparian wetland were responsible for removing NO3- from groundwaters discharging to the Otter Tail River in west central Minnesota. An analysis of river chemistry and flow data revealed that NO3- concentrations in the river increased in the lower half of the 8.3 km study reach as the result of groundwater discharge to the river. Groundwater head measurements along a study transect through the riparian wetland revealed a zone of groundwater discharge extending out under the river. On the basis of combined chemical, dissolved gas, age date, and hydrologic results, it was determined that water chemistry under the riparian wetland was controlled largely by upgradient groundwaters that followed flow paths up to 16 m deep and discharged under the wetland, creating a pattern of progressively older, more chemically reduced, low NO3- water the farther one progressed from the edge of the wetland toward the river. These findings pose challenges for researchers investigating biogeochemical processes in riparian buffer zones because the progressively older groundwaters entered the aquifer in earlier years when less NO3- fertilizer was being used. NO3- concentrations originally present in the groundwater had also decreased in the upgradient aquifer as a result of denitrification and progressively stronger reducing conditions there. The resulting pattern of decreasing NO3- concentrations across the riparian zone may be incorrectly interpreted as evidence of denitrification losses there instead of in the upgradient aquifer. Consequently, it is important to understand the hydrogeologic setting and age structure of the groundwaters being sampled in order to avgid misinterpreting biogeochemical processes in riparian zones.

  8. Riparian zone hydrology and soil water total organic carbon (TOC: implications for spatial variability and upscaling of lateral riparian TOC exports

    Directory of Open Access Journals (Sweden)

    T. Grabs

    2012-10-01

    Full Text Available Groundwater flowing from hillslopes through riparian (near-stream soils often undergoes chemical transformations that can substantially influence stream water chemistry. We used landscape analysis to predict total organic carbon (TOC concentration profiles and groundwater levels measured in the riparian zone (RZ of a 67 km2 catchment in Sweden. TOC exported laterally from 13 riparian soil profiles was then estimated based on the riparian flow–concentration integration model (RIM. Much of the observed spatial variability of riparian TOC concentrations in this system could be predicted from groundwater levels and the topographic wetness index (TWI. Organic riparian peat soils in forested areas emerged as hotspots exporting large amounts of TOC. These TOC fluxes were subject to considerable temporal variations caused by a combination of variable flow conditions and changing soil water TOC concentrations. Mineral riparian gley soils, on the other hand, were related to rather small TOC export rates and were characterized by relatively time-invariant TOC concentration profiles. Organic and mineral soils in RZs constitute a heterogeneous landscape mosaic that potentially controls much of the spatial variability of stream water TOC. We developed an empirical regression model based on the TWI to move beyond the plot scale and to predict spatially variable riparian TOC concentration profiles for RZs underlain by glacial till.

  9. Bright lights, big city: influences of ecological light pollution on reciprocal stream-riparian invertebrate fluxes.

    Science.gov (United States)

    Meyer, Lars A; Sullivan, S Mazeika P

    2013-09-01

    Cities produce considerable ecological light pollution (ELP), yet the effects of artificial night lighting on biological communities and ecosystem function have not been fully explored. From June 2010 to June 2011, we surveyed aquatic emergent insects, riparian arthropods entering the water, and riparian spiders of the family Tetragnathidae at nine stream reaches representing common ambient ELP levels of Columbus, Ohio, USA, streams (low, 0.1-0.5 lux; moderate, 0.6-2.0 lux; high, 2.1-4.0 lux). In August 2011, we experimentally increased light levels at the low- and moderate-treatment reaches to 10-12 lux to represent urban streams exposed to extremely high levels of ELP. Although season exerted the dominant influence on invertebrate fluxes over the course of the year, when analyzed by season, we found that light strongly influenced multiple invertebrate responses. The experimental light addition resulted in a 44% decrease in tetragnathid spider density (P = 0.035), decreases of 16% in family richness (P = 0.040) and 76% in mean body size (P = 0.022) of aquatic emergent insects, and a 309% increase in mean body size of terrestrial arthropods (P = 0.015). Our results provide evidence that artificial light sources can alter community structure and ecosystem function in streams via changes in reciprocal aquatic-terrestrial fluxes of invertebrates. PMID:24147405

  10. Dams, floodplain land use, and riparian forest conservation in the semiarid Upper Colorado River Basin, USA

    Science.gov (United States)

    Andersen, D.C.; Cooper, D.J.; Northcott, K.

    2007-01-01

    Land and water resource development can independently eliminate riparian plant communities, including Fremont cottonwood forest (CF), a major contributor to ecosystem structure and functioning in semiarid portions of the American Southwest. We tested whether floodplain development was linked to river regulation in the Upper Colorado River Basin (UCRB) by relating the extent of five developed land-cover categories as well as CF and other natural vegetation to catchment reservoir capacity, changes in total annual and annual peak discharge, and overall level of mainstem hydrologic alteration (small, moderate, or large) in 26 fourth-order subbasins. We also asked whether CF appeared to be in jeopardy at a regional level. We classified 51% of the 57,000 ha of alluvial floodplain examined along >2600 km of mainstem rivers as CF and 36% as developed. The proportion developed was unrelated to the level of mainstem hydrologic alteration. The proportion classified as CF was also independent of the level of hydrologic alteration, a result we attribute to confounding effects from development, the presence of time lags, and contrasting effects from flow alteration in different subbasins. Most CF (68% by area) had a sparse canopy (???5% cover), and stands with >50% canopy cover occupied conservation of these riparian forests. ?? 2007 Springer Science+Business Media, LLC.

  11. Riparian rehabilitation using vegetation patches: field and laboratory investigations linking hydrology, vegetation and geomorphology

    Science.gov (United States)

    Rodriguez, J. F.; Gorrick, S.

    2010-12-01

    We present results of a riparian revegetation project on an oversized sand stream in eastern Australia. The Widden Brook in New South Wales has undergone extensive widening due to extraordinary floods in the 1950’s and is currently showing some signs of recovery. These include emergence of pool-riffle structure and stabilization of stream width, which are the result of upstream sediment control, riparian revegetation and livestock exclusion. Revegetation of a mild bend was carried out in 2004 using native plants in an arrangement that consisted of three vegetation patches. The same arrangement was tested in a reduced scale model in the laboratory, where extensive measurements of flow, sediment and bed changes provided insight into the links between hydrology, vegetation and geomorphology. Laboratory tests also included runs without vegetation and with a continuous vegetation cover. In terms of bank stability, the patches provided as much protection as the continuous vegetation. Based on the experiments, a series of analytical relationships were developed to help guide the design of vegetation patches focusing on the geomorphic stability of the whole reach instead of concentrating only on the near bank effects.

  12. Associations of breeding birds with fire-influenced and riparian-upland gradients in a longleaf pine ecosystem

    Science.gov (United States)

    Allen, J.C.; Krieger, S.M.; Walters, J.R.; Collazo, J.A.

    2006-01-01

    We determined the effects of fire history and a riparian-upland gradient on the breeding bird community at Fort Bragg Military Installation in North Carolina, one of the largest remnant areas of the endangered longleaf pine (Pinus palustris) ecosystem. Study sites were classified into two treatments: fire-intense (areas experiencing growing-season burns) and fire-suppressed (areas lacking fires). Within each treatment, bird and vegetation data were recorded at point-count stations positioned at three distances from streamhead pocosins to characterize the riparian-upland habitat gradient: 0, 75, and ???150 m. Total bird abundance and species richness varied significantly along the riparian-upland gradient, with pocosins contributing greatly to avian biodiversity. Our data revealed strong effects of fire history and riparian-upland gradient on bird species, which we described in terms of breeding-bird assemblages. Members of the open longleaf assemblage (e.g., Red-cockaded Woodpecker [Picoides borealis], Bachman's Sparrow [Aimophila aestivalis]) were most common in fire-intense areas and at upland locations. Members of the fire-suppressed assemblage (e.g., Wood Thrush [Hylocichla mustelina], Ovenbird [Seiurus aurocapilla]) were confined to pocosins in fire-intense areas, but became more abundant in fire-suppressed areas. Members of the pocosin assemblage (e.g., Eastern Towhee [Pipilo erythropthalamus], Common Yellowthroat [Geothlypis trichas]) were largely confined to pocosins and, in some cases, were most abundant in fire-intense pocosins. Fire suppression increased structural diversity of vegetation and promoted one breeding-bird assemblage (fire-suppressed), but at the expense of two others (open longleaf, pocosin). Continued management of Fort Bragg to promote longleaf pine restoration is essential for supporting conservation of the open-longleaf bird assemblage; in addition, it will benefit the pocosin assemblage. ?? The American Ornithologists' Union, 2006.

  13. Riparian restoration framework for the Upper Gila River, Arizona

    Science.gov (United States)

    Orr, Bruce K.; Leverich, Glen L.; Diggory, Zooey E.; Dudley, Tom L.; Hatten, James R.; Hultine, Kevin R.; Johnson, Matthew P.; Orr, Devyn A.

    2014-01-01

    This technical report summarizes the methods and results of a comprehensive riparian restoration planning effort for the Gila Valley Restoration Planning Area, an approximately 53-mile portion of the upper Gila River in Arizona (Figure 1-1). This planning effort has developed a Restoration Framework intended to deliver science-based guidance on suitable riparian restoration actions within the ecologically sensitive river corridor. The framework development was conducted by a restoration science team, led by Stillwater Sciences with contributions from researchers at the Desert Botanical Garden (DBG), Northern Arizona University (NAU), University of California at Santa Barbara (UCSB), and U.S. Geological Survey (USGS). All work was coordinated by the Gila Watershed Partnership of Arizona (GWP), whose broader Upper Gila River Project Area is depicted in Figure 1-1, with funding from the Walton Family Foundation’s Freshwater Initiative Program.

  14. Evaluation of nitrate dynamics in riparian zones using environmental isotopes

    International Nuclear Information System (INIS)

    Nitrate contamination, often associated with agricultural activities, is a major problem in some shallow aquifers in Canada and is an increasing threat to groundwater supplies and surface water quality. The studies to be presented at this conference are part of a major project aiming to examine the function of riparian zones in watersheds dominated by agricultural areas. Specifically, this project focuses on the role of vegetation strips and wetlands as buffer zones to attenuate groundwater nitrate generated by agricultural activities, that ultimately impact surface water. Our research approach involves combining the hydrology, geochemistry, ecology and stratigraphic analyses of the riparian zone in a multi-disciplinary way. 15N and 18O in nitrate are being used to provide information on the sources and to allow us to separate denitrification from nitrate attenuation by dilution

  15. Wildlife Response to Riparian Restoration on the Sacramento River

    OpenAIRE

    Golet, Gregory H.; Gardali, Thomas; Howell, Christine A.; Hunt, John; Luster, Ryan A.; Rainey, William; Roberts, Michael D; Silveira, Joseph; Swagerty, Helen; Williams, Neal

    2008-01-01

    Studies that assess the success of riparian restoration projects seldom focus on wildlife. More generally, vegetation characteristics are studied, with the assumption that animal populations will recover once adequate habitats are established. On the Sacramento River, millions of dollars have been spent on habitat restoration, yet few studies of wildlife response have been published. Here we present the major findings of a suite of studies that assessed responses of four taxonomic groups (ins...

  16. Riparian deforestation, stream narrowing, and loss of stream ecosystem services.

    Science.gov (United States)

    Sweeney, Bernard W; Bott, Thomas L; Jackson, John K; Kaplan, Louis A; Newbold, J Denis; Standley, Laurel J; Hession, W Cully; Horwitz, Richard J

    2004-09-28

    A study of 16 streams in eastern North America shows that riparian deforestation causes channel narrowing, which reduces the total amount of stream habitat and ecosystem per unit channel length and compromises in-stream processing of pollutants. Wide forest reaches had more macroinvertebrates, total ecosystem processing of organic matter, and nitrogen uptake per unit channel length than contiguous narrow deforested reaches. Stream narrowing nullified any potential advantages of deforestation regarding abundance of fish, quality of dissolved organic matter, and pesticide degradation. These findings show that forested stream channels have a wider and more natural configuration, which significantly affects the total in-stream amount and activity of the ecosystem, including the processing of pollutants. The results reinforce both current policy of the United States that endorses riparian forest buffers as best management practice and federal and state programs that subsidize riparian reforestation for stream restoration and water quality. Not only do forest buffers prevent nonpoint source pollutants from entering small streams, they also enhance the in-stream processing of both nonpoint and point source pollutants, thereby reducing their impact on downstream rivers and estuaries. PMID:15381768

  17. Responses of riparian reptile communities to damming and urbanization

    Science.gov (United States)

    Hunt, Stephanie D.; Guzy, Jacquelyn C.; Price, Steven J.; Halstead, Brian J.; Eskew, Evan A.; Dorcas, Michael E.

    2013-01-01

    Various anthropogenic pressures, including habitat loss, threaten reptile populations worldwide. Riparian zones are critical habitat for many reptile species, but these habitats are also frequently modified by anthropogenic activities. Our study investigated the effects of two riparian habitat modifications-damming and urbanization-on overall and species-specific reptile occupancy patterns. We used time-constrained search techniques to compile encounter histories for 28 reptile species at 21 different sites along the Broad and Pacolet Rivers of South Carolina. Using a hierarchical Bayesian analysis, we modeled reptile occupancy responses to a site's distance upstream from dam, distance downstream from dam, and percent urban land use. The mean occupancy response by the reptile community indicated that reptile occupancy and species richness were maximized when sites were farther upstream from dams. Species-specific occupancy estimates showed a similar trend of lower occupancy immediately upstream from dams. Although the mean occupancy response of the reptile community was positively related to distance downstream from dams, the occupancy response to distance downstream varied among species. Percent urban land use had little effect on the occupancy response of the reptile community or individual species. Our results indicate that the conditions of impoundments and subsequent degradation of the riparian zones upstream from dams may not provide suitable habitat for a number of reptile species.

  18. Examining water quality effects of riparian wetland loss and restoration scenarios in a southern ontario watershed.

    Science.gov (United States)

    Yang, Wanhong; Liu, Yongbo; Ou, Chunping; Gabor, Shane

    2016-06-01

    Wetland conservation has two important tasks: The first is to halt wetland loss and the second is to conduct wetland restoration. In order to facilitate these tasks, it is important to understand the environmental degradation from wetland loss and the environmental benefits from wetland restoration. The purpose of the study is to develop SWAT based wetland modelling to examine water quality effects of riparian wetland loss and restoration scenarios in the 323-km(2) Black River watershed in southern Ontario, Canada. The SWAT based wetland modelling was set up, calibrated and validated to fit into watershed conditions. The modelling was then applied to evaluate various scenarios of wetland loss from existing 7590 ha of riparian wetlands (baseline scenario) to 100% loss, and wetland restoration up to the year 1800 condition with 11,237 ha of riparian wetlands (100% restoration). The modelling was further applied to examine 100% riparian wetland loss and restoration in three subareas of the watershed to understand spatial pattern of water quality effects. Modelling results show that in comparing to baseline condition, the sediment, total nitrogen (TN), and total phosphorus (TP) loadings increase by 251.0%, 260.5%, and 890.9% respectively for 100% riparian wetland loss, and decrease by 34.5%, 28.3%, and 37.0% respectively for 100% riparian wetland restoration. Modelling results also show that as riparian wetland loss increases, the corresponding environmental degradation worsens at accelerated rates. In contrast, as riparian wetland restoration increases, the environmental benefits improve but at decelerated rates. Particularly, the water quality effects of riparian wetland loss or restoration show considerable spatial variations. The watershed wetland modelling contributes to inform decisions on riparian wetland conservation or restoration at different rates. The results further demonstrate the importance of targeting priority areas for stopping riparian wetland loss

  19. Modelling riparian buffers for water quality enhancement in the Karapiro catchment

    OpenAIRE

    Ramilan, Thiagarajah; Scrimgeour, Frank G.; Marsh, Dan

    2010-01-01

    The use of riparian land buffers is widely promoted as a method of mitigating the effects of sediment and nutrient runoff from intensive land use in New Zealand. Farmers receive advice and financial assistance from Regional Councils for activities such as establishment and planting of riparian buffers, but funding is limited. The effect of buffers on water quality goals varies across land types so the optimum size of riparian buffer width varies across farms. We build a stylised model to dete...

  20. Seedling production of woody riparian species from seeds: techniques and results

    OpenAIRE

    Fabião, António; Carneiro, Marta; Pimentel, Filipa; Fabião, André

    2007-01-01

    Rehabilitation of woody riparian galleries largely depends on the availability of seedlings or seeds of autochthonous species, which are usually difficult to obtain in Portugal. The cultural value of autochthonous seeds of several riparian woody species in nursery conditions was evaluated in order to assess seedling production feasibility. The choice of species was based on their occurrence in riparian habitats, even if not exclusive to such environments, and their suitability to establishmen...

  1. Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

    Science.gov (United States)

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2007-09-01

    flux from dominant riparian vegetation adjacent to the stream channel. Results from this investigation show that the population structure of dioecious riparian trees has direct consequences on ecosystem ET, particularly along stream margins. Shifts in population structure therefore, may have profound impacts on several ecohydrological processes including stream discharge, biogeochemical cycling, and ecosystem productivity.

  2. Effect of gender on sap-flux-scaled transpiration in a dominant riparian tree species: Box elder (Acer negundo)

    Science.gov (United States)

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2007-09-01

    Acer negundo is a dioecious riparian tree species with a spatial segregation of the sexes along soil moisture gradients. Females are typically more common in wet sites along streams (typically F/M ≈ 1.6), whereas males are more common in drier sites away from streams (typically F/M ≈ 0.6). Spatial segregation between sexes may develop because of the higher reproductive cost in females compared to males. If so, female Acer negundo trees would be under stronger selection to maximize resource uptake, and would therefore likely occur at greater frequencies in high resources sites (i.e., along streamsides), and increase rates of resource acquisition (i.e., water and nutrients). The spatial segregation of the sexes leads to the hypothesis that male and female individuals have varying influence on ecosystem evapotranspiration. To address this, stem sap flux was measured on mature streamside (≤1 m from stream channel) and nonstreamside (>1 m from stream channel) male and female Acer negundo trees occurring in Red Butte Canyon near Salt Lake City, Utah, during the 2004 growing season. Despite having similar predawn and midday water potentials, sap flux density was 76% higher in streamside female trees than in males (P active radiation (P = 0.0263). At the watershed scale, nonstreamside male and female A. negundo trees contributed 20 and 21% respectively to the estimated 1.7 mm d-1 transpiration flux from dominant riparian vegetation away from streamsides (estimated from scaled sap flux measurements of all dominant riparian tree species in Red Butte Canyon). Male and female A. negundo trees contributed 31 and 46% respectively of the estimated 8.0 mm d-1 transpiration flux from dominant riparian vegetation adjacent to the stream channel. Results from this investigation show that the population structure of dioecious riparian trees has direct consequences on ecosystem ET, particularly along stream margins. Shifts in population structure therefore, may have profound

  3. Headwater riparian forest-floor invertebrate communities associated with alternative forest management practices.

    Science.gov (United States)

    Rykken, Jessica J; Moldenke, Andrew R; Olson, Deanna H

    2007-06-01

    Headwater streams and their riparian zones are a common, yet poorly understood, component of Pacific Northwest, USA, landscapes. We describe the ecological importance of headwater stream riparian zones as habitat for forest-floor invertebrate communities and assess how alternative management strategies for riparian zones may impact these communities. We compared community composition of forest-floor invertebrates at increasing distances along trans-riparian (stream edge to upslope) transects in mature forests, clearcuts, and riparian buffers of approximately 30-m width with upslope clearcuts. Invertebrates were collected using pitfall traps in five replicate blocks of three treatments each in the Willamette National Forest, Oregon, USA. We measured microclimate and microhabitat variables at pitfall locations. Despite strong elevation and block effects on community composition, community analyses revealed a distinct "riparian" invertebrate community within 1 m of the stream edge in mature forest treatments, which was strongly related to cool, humid microclimate conditions. Invertebrate community composition in buffer treatments was far more similar to that of mature forests than to clearcuts; a pattern mirrored by microclimate. These results suggest that, within our study sites, forest-floor invertebrate distributions are strongly associated with microclimate and that riparian buffers of approximately 30-m width do provide habitat for many riparian and forest species. Riparian reserves may serve as effective forest refugia and/or dispersal corridors for invertebrates and other taxa, and their incorporation into watershed management plans likely will contribute to meeting persistence and connectivity objectives. PMID:17555226

  4. Denitrification controls in urban riparian soils: implications for reducing urban nonpoint source nitrogen pollution.

    Science.gov (United States)

    Li, Yangjie; Chen, Zhenlou; Lou, Huanjie; Wang, Dongqi; Deng, Huanguang; Wang, Chu

    2014-09-01

    The purpose of this research was to thoroughly analyze the influences of environmental factors on denitrification processes in urban riparian soils. Besides, the study was also carried out to identify whether the denitrification processes in urban riparian soils could control nonpoint source nitrogen pollution in urban areas. The denitrification rates (DR) over 1 year were measured using an acetylene inhibition technique during the incubation of intact soil cores from six urban riparian sites, which could be divided into three types according to their vegetation. The soil samples were analyzed to determine the soil organic carbon (SOC), soil total nitrogen (STN), C/N ratio, extractable NO3 (-)-N and NH4 (+)-N, pH value, soil water content (SWC), and the soil nitrification potential to evaluate which of these factors determined the final outcome of denitrification. A nitrate amendment experiment further indicated that the riparian DR was responsive to added nitrate. Although the DRs were very low (0.099 ~ 33.23 ng N2O-N g(-1) h(-1)) due to the small amount of nitrogen moving into the urban riparian zone, the spatial and temporal patterns of denitrification differed significantly. The extractable NO3 (-)-N proved to be the dominant factor influencing the spatial distribution of denitrification, whereas the soil temperature was a determinant of the seasonal DR variation. The six riparian sites could also be divided into two types (a nitrate-abundant and a nitrate-stressed riparian system) according to the soil NO3 (-)-N concentration. The DR in nitrate-abundant riparian systems was significantly higher than that in the nitrate-stressed riparian systems. The DR in riparian zones that were covered with bushes and had adjacent cropland was higher than in grass-covered riparian sites. Furthermore, the riparian DR decreased with soil depth, which was mainly attributed to the concentrated nitrate in surface soils. The DR was not associated with the SOC, STN, C/N ratio, and

  5. Relation between fish communities and riparian zone conditions at two spatial scales

    Science.gov (United States)

    Lee, K.E.; Goldstein, R.M.; Hanson, P.E.

    2001-01-01

     The relation offish community composition to riparian cover at two spatial scales was compared at 18 streams in the agricultural Minnesota River Basin. The two spatial scales were: (1) local riparian zone (a 200 meter wide buffer extending 2 to 3 kilometers upstream of the sampling reach); and (2) the upstream riparian zone (a 200 m wide buffer on the mainstem and all perennial tributaries upstream of the sampling reach). Analysis of variance indicated that streams with wooded-local riparian zones had greater fish species richness (means = 20 and 15, respectively) and Index of Biotic Integrity (IBI) scores (means = 40 and 26, respectively) than streams with open-local riparian zones. Streams with wooded-upstream riparian zones tended (were not statistically significant) to have greater numbers of species (means = 19 and 15, respectively) and IBI scores (means = 33 and 28, respectively) than streams with open-upstream riparian zones. There was no significant interaction between the riparian zone conditions at the two scales. This study suggests that maintenance of wooded riparian cover along streams could be effective in maintaining or improving fish community composition in streams draining heavily agricultural areas.

  6. Riparian strip efficiency assessment in agricultural landscapes using stereoscopic very high spatial resolution satellite imagery

    Science.gov (United States)

    Chokmani, Karem; Novoa, Julio

    2015-04-01

    Riparian strips are used worldwide to protect riverbanks and water quality in agricultural zones because of their several environmental benefits. A metric called the Riparian Strip Quality Index, which is based on the percentage area of riverine vegetation found on the riparian strip, is used to evaluate their ecological condition. This index could be considered an indicator of the potential capacity of riparian strips to filter sediments, retain pollutants, and provide shelter to terrestrial and aquatic species. Thus, in order to know if a riparian strip is truly efficient in agricultural lands, which means that it is fulfilling those ecological functions, it is necessary to understand their ability to intercept surface runoff. The latter is the major cause of water pollution and erosion in these productive areas. Besides vegetation coverage, topographic and hydrologic parameters must be included to model the intensity and spatial distribution of runoff streamflow at local scales. The geospatial information used to assess the ecological efficiency of riparian strips was extracted from very-high-spatial-resolution WorldView-2 satellite imagery. This information was then processed using current geospatial techniques such as object-based image analysis and was used to develop a Riparian Strip Efficiency Index. The results show that this index might be used to assess the efficiency of riparian strips, which will enable land managers to monitor changes occurring over time, identify priority areas for restoration activities. This, in turn, might ensure optimal allocation of private or public funds towards the most inefficient and threatened riparian strips.

  7. Multicriteria analysis to evaluate the energetic reuse of riparian vegetation

    International Nuclear Information System (INIS)

    The management of riparian vegetation which includes cutting operations of grass, reeds, bushes and trees, is very important to reduce hydrogeologic risk. In Tuscany, riparian biomass and residues are mainly left shredded along courses or disposed in landfills as special wastes: actually different laws prohibit that tree trunks are abandoned in areas naturally affected by flooding, because they can be moved contributing to increase the water level and to maximize the hydraulic risk of some other nearby areas. In some cases, it is also possible to store the logs in specified sites from where they can be taken and used as a fuel in fireplaces or domestic heating plants. This work studies the possibility of the reuse of riparian vegetation as biomass for energy production and evaluates benefits and drawbacks from the economical, environmental and managerial points of view. Particularly, a specific methodology has been developed for two hydrological districts of Tuscany, with different typologies and densities of vegetation. First, an estimation of biomass distribution on the land and an evaluation of annual wood availability have been carried out; then, different chains concerning harvesting operation, biomass transport, storage conditions and final utilisation, have been defined and compared by a specific multicriteria analysis (MCA); finally, for the most suitable bio-energy chains the Life Cycle Assessment (LCA) has been implemented. Results of the LCA have also permitted to validate some environmental indicators used in the MCA, as mechanisation level of yards, energy efficiency of plants or transport distances. The decision making tool developed allows to compare costs and environmental benefits of the energy use of riparian vegetation, supporting local authorities involved in energy planning: in this way it is possible to confront different alternatives to match the energy demand and meet the energy saving and sustainability issues at the lowest cost for the

  8. Multicriteria analysis to evaluate the energetic reuse of riparian vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Recchia, Lucia; Cini, Enrico [Dipartimento di Ingegneria Agraria e Forestale, Universita di Firenze, Piazzale delle Cascine 15, 50144 Firenze (Italy); Corsi, Stefano [Consorzio di Bonifica per la difesa del suolo e la tutela dell' ambiente della Toscana Centrale, via Verdi 16, 50122 Firenze (Italy)

    2010-01-15

    The management of riparian vegetation which includes cutting operations of grass, reeds, bushes and trees, is very important to reduce hydrogeologic risk. In Tuscany, riparian biomass and residues are mainly left shredded along courses or disposed in landfills as special wastes: actually different laws prohibit that tree trunks are abandoned in areas naturally affected by flooding, because they can be moved contributing to increase the water level and to maximize the hydraulic risk of some other nearby areas. In some cases, it is also possible to store the logs in specified sites from where they can be taken and used as a fuel in fireplaces or domestic heating plants. This work studies the possibility of the reuse of riparian vegetation as biomass for energy production and evaluates benefits and drawbacks from the economical, environmental and managerial points of view. Particularly, a specific methodology has been developed for two hydrological districts of Tuscany, with different typologies and densities of vegetation. First, an estimation of biomass distribution on the land and an evaluation of annual wood availability have been carried out; then, different chains concerning harvesting operation, biomass transport, storage conditions and final utilisation, have been defined and compared by a specific multicriteria analysis (MCA); finally, for the most suitable bio-energy chains the Life Cycle Assessment (LCA) has been implemented. Results of the LCA have also permitted to validate some environmental indicators used in the MCA, as mechanisation level of yards, energy efficiency of plants or transport distances. The decision making tool developed allows to compare costs and environmental benefits of the energy use of riparian vegetation, supporting local authorities involved in energy planning: in this way it is possible to confront different alternatives to match the energy demand and meet the energy saving and sustainability issues at the lowest cost for the

  9. [Spatial variation in riparian soil properties and its response to environmental factors in typical reach of the middle and lower reaches of the Yellow River].

    Science.gov (United States)

    Zhao, Qing-he; Liu, Qian; Ma, Li-jiao; Ding, Sheng-yan; Lu, Xun-ling; Tang, Qian; Xu, Shan-shan

    2015-12-01

    Soil and vegetation are the foundation of maintaining riparian ecosystem services, and their spatial distribution and variations can determine the effects of ecological functions. In the present study, selecting the typical reach of the middle and lower reaches of the Yellow River as the study area, the spatial distributions of riparian soil physicochemical properties and their response to environmental factors were analyzed by employing methods of field investigation, experimental analysis, and redundancy analysis (RDA). The results showed that soil particle was composed significantly of silt in the study area, with the increase of riparian buffer distance, soil bulk density increased initially and then decreased, whereas soil moisture showed the opposite pattern. Changes in total soil phosphorus (TP), available phosphorus (AP), total carbon (TC), total organic carbon (TOC), total nitrogen (TN); ammonium nitrogen (NH₄⁺-N) and nitrate nitrogen (NO₃⁻-N) contents under different riparian buffer distance showed no statistically significant differences. The spatial distribution of soil chemical properties was generally insignificantly different through changes between two vegetation types. Pearson correlation analysis showed that there was close relationship between soil physical and chemical properties, therein, TOC content in the study area was positively and significantly related to TN (P DBH) of the tree layer and coverage of the herb layer. Meanwhile, with the increase of elevation gradient, the content of soil NH₄⁺-N presented an increasing trend, indicating that soil properties were significantly influenced by the effects of community structure and elevation gradient in the study area. PMID:27112021

  10. Testing the effects of an introduced palm on a riparian invertebrate community in southern California.

    Directory of Open Access Journals (Sweden)

    Theresa Sinicrope Talley

    Full Text Available Despite the iconic association of palms with semi-arid regions, most are introduced and can invade natural areas. Along the San Diego River (San Diego, California, USA, the introduced Canary Island date palm (Phoenix canariensis forms dense patches among native riparian shrubs like arroyo willow (Salix lasiolepis. The structural differences between the palm and native shrubs are visually obvious, but little is known about palm's effects on the ecosystem. We tested for the effects of the palm on a riparian invertebrate community in June 2011 by comparing the faunal and environmental variables associated with palm and willow canopies, trunks and ground beneath each species. The palm invertebrate community had lower abundance and diversity, fewer taxa feeding on the host (e.g., specialized hemipterans, and more taxa likely using only the plant's physical structure (e.g., web-builders, oak moths, willow hemipterans. There were no observed effects on the ground-dwelling fauna. Faunal differences were due to the physical and trophic changes associated with palm presence, namely increased canopy density, unpalatable leaves, trunk rugosity, and litter accumulations. Palm presence and resulting community shifts may have further ecosystem-level effects through alteration of physical properties, food, and structural resources. These results were consistent with a recent study of invasive palm effects on desert spring arthropods, illustrating that effects may be relatively generalizable. Since spread of the palm is largely localized, but effects are dramatic where it does occur, we recommend combining our results with several further investigations in order to prioritize management decisions.

  11. Riparian zone processes and soil water total organic carbon (TOC): implications for spatial variability, upscaling and carbon exports

    OpenAIRE

    T. Grabs; K. H. Bishop; Laudon, H.; Lyon, S. W.; Seibert, J.

    2012-01-01

    Groundwater flowing from hillslopes through riparian (near stream) soils often undergoes chemical transformations that can substantially influence stream water chemistry. We used landscape analysis to predict total organic carbon (TOC) concentrations profiles and groundwater levels measured in the riparian zone (RZ) of a 67 km2 catchment in Sweden. TOC exported from 13 riparian soil profiles was then estimated based on the riparian flow-concentration integration mo...

  12. Mycorrhizas effects on nutrient interception in two riparian grass species

    Directory of Open Access Journals (Sweden)

    Hamid Reza Asghari

    2014-12-01

    Full Text Available Effects of arbuscular mycorrhizal (AM fungi on plant growth and soil nutrient depletion are well known, but their roles as nutrient interceptor in riparian areas are less clear. The effects of AM fungi on growth, soil nutrient depletion and nutrient leaching were investigated in columns with two riparian grass species. Mycorrhizal and non mycorrhizal (NM plants were grown in a mixture of riparian soil and sand (60% and 40%, w/w respectively for 8 weeks under glasshouse conditions. Mycorrhizal colonization, AM external hyphae development, plant growth, nutrient uptake and NO3, NH4 and available P in soil and leachate were measured. Mycorrhizal fungi highly colonized roots of exotic grass Phalaris aquatica and significantly increased plant growth and nutrient uptake. Columns containing of AM Phalaris aquatica had higher levels of AM external hyphae, lower levels of NO3, NH4 and available P in soil and leachate than NM columns. Although roots of native grass Austrodanthonia caespitosa had moderately high levels of AM colonization and AM external hyphae in soil, AM inoculation had no significant effects on plant growth, soil and leachate concentration of NO3 and NH4. But AM inoculation decreased available soil P concentration in deeper soil layer and had no effects on dissolved P in leachate. Although both grass species had nearly the same biomass, results showed that leachate collected from Austrodanthonia caespitosa columns significantly had lower levels of NO3, NH4 and dissolve P than leachate from exotic Phalaris aquatica columns. Taken together, these data shows that native plant species intercept higher nutrient than exotic plant species and had no responsiveness to AM fungi related to nutrient leaching, but AM fungi play an important role in interception of nutrient in exotic plant species.

  13. Linking channel hydrology with riparian wetland accretion in tidal rivers

    Science.gov (United States)

    Ensign, Scott H.; Noe, Gregory B.; Hupp, Cliff R.

    2014-01-01

    The hydrologic processes by which tide affects river channel and riparian morphology within the tidal freshwater zone are poorly understood, yet are fundamental to predicting the fate of coastal rivers and wetlands as sea level rises. We investigated patterns of sediment accretion in riparian wetlands along the non-tidal through oligohaline portion of two coastal plain rivers in Maryland, U.S.A., and how flow velocity, water level, and suspended sediment concentration (SSC) in the channel may have contributed to those patterns. Sediment accretion was measured over a one year period using artificial marker horizons, channel hydrology was measured over a one month period using acoustic Doppler current profilers, and SSC was predicted from acoustic backscatter. Riparian sediment accretion was lowest at the non-tidal sites (mean and standard deviation = 8 ± 8 mm yr-1), highest at the upstream tidal freshwater forested wetlands (TFFW) (33 ± 28 mm yr-1), low at the midstream TFFW (12 ± 9 mm yr-1), and high at the oligohaline (fresh-to-brackish) marshes (19 ± 8 mm yr-1). Channel maximum flood and ebb velocity was 2-fold faster at the oligohaline than tidal freshwater zone on both tidal rivers, corresponding with the differences in in-channel SSC: the oligohaline zone's SSC was more than double the tidal freshwater zone's, and was greater than historical SSC at the non-tidal gages. The tidal wave characteristics differed between rivers, leading to significantly greater in-channel SSC during floodplain inundation in the weakly convergent than the strongly convergent tidal river. Overall sediment accretion was higher in the embayed river likely due to a single storm discharge and associated sedimentation.

  14. Valuation Challenges of Riparian Restoration in a Dynamic Decision Support Context: What Could Possibly Go Wrong?

    Science.gov (United States)

    A dynamic simulation model is constructed to compare benefit-cost ratios of riparian restoration options for the Middle Rio Grande riparian corridor in Albuquerque, New Mexico, USA. The model is built from original choice experiment valuation data, regional benefit-transfer studi...

  15. Denitrification and Nitrate Consumption in an Herbaceous Riparian Area and Perennial Ryegrass Seed Field

    Science.gov (United States)

    Riparian ecosystems have the capacity to lower NO3- concentrations in groundwater entering from non-point agricultural sources. The microbial processes responsible for decreases in riparian groundwater NO3- concentrations in the Willamette Valley of Oregon are not well understood. Our objective was...

  16. Runoff water quality from manured riparian grasslands with contrasting soil drainage and simulated grazing pressure

    Science.gov (United States)

    Globally, management of grazed riparian areas is of critical importance in terms of agricultural sustainability and environmental quality. However, the potential impacts of riparian grazing management on water quality are not well documented, particularly in the southeastern USA. The objective of ...

  17. Mapping Variable Width Riparian Zones Utilizing Open Source Data: A Robust New Approach

    Science.gov (United States)

    Abood, S. A.; Maclean, A.

    2013-12-01

    Riparian buffers are dynamic, transitional ecosystems between aquatic and terrestrial ecosystems with well-defined vegetation and soil characteristics. Previous approaches to riparian buffer delineation have primarily utilized fixed width buffers. However, these methodologies only take the watercourse into consideration and ignore critical geomorphology, associated vegetation and soil characteristics. Utilizing spatial data readily available from government agencies and geospatial clearinghouses, such as DEMs and the National Hydrography Dataset, the Riparian Buffer Delineation Model (RBDM) offers advantages by harnessing the geospatial modeling capabilities of ArcMap GIS, incorporating a statistically valid sampling technique along the watercourse to accurately map the critical 50-year plain, and delineating a variable width riparian buffer. Options within the model allow incorporation of National Wetlands Inventory (NWI), Soil Survey Data (SSURGO), National Land Cover Data (NLCD) and/or Cropland Data Layer (CDL) to improve the accuracy and utility of the riparian buffers attributes. This approach recognizes the dynamic and transitional natures of riparian buffers by accounting for hydrologic, geomorphic and vegetation data as inputs into the delineation process. By allowing the incorporation of land cover data, decision makers acquire a useful tool to assist in managing riparian buffers. The model is formatted as an ArcMap toolbox for easy installation and does require a Spatial Analyst license. Variable width riparian buffer utilizing 50-year flood height and 10m DEM. RBDM Inputs

  18. Influence of Herbaceous Riparian Buffers on Channelized Headwater Streams in Central Ohio

    Science.gov (United States)

    Herbaceous riparian buffers are a widely used conservation practice in the United States for reducing nutrient, pesticide, and sediment loadings in agricultural streams. The importance of forested riparian buffers for headwater streams has been documented, but the ecological impacts of herbaceous ri...

  19. Analysis of microbial populations, denitrification, and nitrous oxide production in riparian buffers

    Science.gov (United States)

    Riparian buffers are used extensively to protect water bodies from nonpoint source nitrogen pollution. However there is relatively little information on the impact of these buffers on production of nitrous oxide (N2O). In this study, we assessed nitrous oxide production in riparian buffers of the so...

  20. Forest transpiration from sap flux density measurements in a Southeastern Coastal Plain riparian buffer system

    Science.gov (United States)

    Forested riparian buffers are prevalent throughout the Southeastern Coastal Plain Region of the United States (US). Because they make up a significant portion of the regional landscape, transpiration within these riparian buffers is believed to have an important impact on the hydrologic budget of r...

  1. Identifying Riparian Buffer Effects on Stream 1 Nitrogen in Southeastern Coastal Plain Watersheds

    Science.gov (United States)

    Riparian areas have long demonstrated their ability to attenuate nutrients and sediments from agricultural runoff at the field scale; however, to inform effective nutrient management choices, the impact of riparian buffers on water quality services must be assessed at watershed s...

  2. Aquatic grazers reduce the establishment and growth of riparian plants along an environmental gradient

    NARCIS (Netherlands)

    Veen, G.F.; Sarneel, J.M.; Ravensbergen, L.; Huig, N.; van Paassen, J.; Rip, W.; Bakker, E.S.

    2013-01-01

    Summary The establishment of riparian plants is determined by abiotic conditions and grazing, although it is usually presumed that the former are most important. We tested the impact of aquatic grazers on the survival and growth of establishing riparian plants and whether the impact of grazing inter

  3. A SUSTAINABLE APPROACH TO NITRATE REDUCTION COMBINING A RIPARIAN ZONE WITH A STREAM DENITRIFYING BIOFILM

    Science.gov (United States)

    1) an optimum riparian zone design based on native or non-invasive plants to Southern Virginia and expected flow conditions and 2) an optimum biofilm design based on the ability to augment the riparian zone during inefficient times at the same conditions.

  4. Small mammals in saltcedar (Tamarix ramosissima) - invaded and native riparian habitats of the western Great Basin

    Science.gov (United States)

    Invasive saltcedar species have replaced native riparian trees on numerous river systems throughout the western US, raising concerns about how this habitat conversion may affect wildlife. For periods ranging from 1-10 years, small mammal populations were monitored at six riparian sites impacted by s...

  5. The impact of flood variables on riparian vegetation

    Science.gov (United States)

    Dzubakova, Katarina; Molnar, Peter

    2016-04-01

    The riparian vegetation of Alpine rivers often grows in temporally dynamic riverine environments which are characterized by pronounced meteorological and hydrological fluctuations and high resource competition. Within these relatively rough conditions, riparian vegetation fulfils essential ecosystem functions such as water retention, biomass production and habitat to endangered species. The identification of relevant flood attributes impacting riparian vegetation is crucial for a better understanding of the vegetation dynamics in the riverine ecosystem. Hence, in this contribution we aim to quantify the ecological effects of flood attributes on riparian vegetation and to analyze the spatial coherence of flood-vegetation interaction patterns. We analyzed a 500 m long and 300-400 m wide study reach located on the Maggia River in southern Switzerland. Altogether five floods between 2008 and 2011 with return periods ranging from 1.4 to 20.1 years were studied. To assess the significance of the flood attributes, we compared post-flood to pre-flood vegetation vigour to flood intensity. Pre- and post-flood vegetation vigour was represented by the Normalized Difference Vegetation Index (NDVI) which was computed from images recorded by high resolution ground-based cameras. Flood intensity was expressed in space in the study reach by six flood attributes (inundation duration, maximum depth, maximum and total velocity, maximum and total shear stress) which were simulated by the 2D hydrodynamic model BASEMENT (VAW, ETH Zurich). We considered three floodplain units separately (main bar, secondary bar, transitional zone). Based on our results, pre-flood vegetation vigour largely determined vegetation reaction to the less intense floods (R = 0.59-0.96). However for larger floods with a strong erosive effect, its contribution was significantly lower (R = 0.59-0.68). Using multivariate regression analysis we show that pre-flood vegetation vigour and maximum velocity proved to be

  6. 2004 progress report : Effects of ungulate browsing on post-fire recovery of riparian cottonwoods : Implications for management of riparian forests, Seedskadee National Wildlife Refuge, Wyoming

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Browsing pressure by ungulates may limit natural establishment of native cottonwood and willow stands, and fires, which have become more frequent on riparian lands...

  7. Holding onto the Green Zone: A Youth Program for the Study and Stewardship of Community Riparian Areas. Action Guide

    Science.gov (United States)

    US Department of the Interior, 2008

    2008-01-01

    Scientists call the land along the edges of a river, stream, or lake a riparian zone. In this guide, riparian zone will be called the Green Zone. Riparian zones make up only a small part of land in the United States. But they are very important. They protect water quality and quantity, supply food and shelter for fish and wildlife, and provide…

  8. Seeing the Forest through the Trees: Citizen Scientists Provide Critical Data to Refine Aboveground Carbon Estimates in Restored Riparian Forests

    Science.gov (United States)

    Viers, J. H.

    2013-12-01

    Integrating citizen scientists into ecological informatics research can be difficult due to limited opportunities for meaningful engagement given vast data streams. This is particularly true for analysis of remotely sensed data, which are increasingly being used to quantify ecosystem services over space and time, and to understand how land uses deliver differing values to humans and thus inform choices about future human actions. Carbon storage and sequestration are such ecosystem services, and recent environmental policy advances in California (i.e., AB 32) have resulted in a nascent carbon market that is helping fuel the restoration of riparian forests in agricultural landscapes. Methods to inventory and monitor aboveground carbon for market accounting are increasingly relying on hyperspatial remotely sensed data, particularly the use of light detection and ranging (LiDAR) technologies, to estimate biomass. Because airborne discrete return LiDAR can inexpensively capture vegetation structural differences at high spatial resolution ( 1000 ha), its use is rapidly increasing, resulting in vast stores of point cloud and derived surface raster data. While established algorithms can quantify forest canopy structure efficiently, the highly complex nature of native riparian forests can result in highly uncertain estimates of biomass due to differences in composition (e.g., species richness, age class) and structure (e.g., stem density). This study presents the comparative results of standing carbon estimates refined with field data collected by citizen scientists at three different sites, each capturing a range of agricultural, remnant forest, and restored forest cover types. These citizen science data resolve uncertainty in composition and structure, and improve allometric scaling models of biomass and thus estimates of aboveground carbon. Results indicate that agricultural land and horticulturally restored riparian forests store similar amounts of aboveground carbon

  9. Stream characteristics and their implications for the protection of riparian fens and meadows

    DEFF Research Database (Denmark)

    Baattrup-Pedersen, A.; Larsen, S.E.; Andersen, Peter Mejlhede;

    2011-01-01

    1. Running waters, including associated riparian areas, are embraced by international legal frameworks outlining targets for the preservation, protection and improvement of the quality of the environment. Interactions between stream and river processes and riparian habitats have not received much...... riparian areas, affecting conditions needed to sustain protected fen and meadow communities. 4. We also found that water chemistry strongly influenced the occurrence of fen and meadow vegetation in riparian areas. The probability of finding fen and meadow vegetation was reduced when total phosphorus (TP...... influence of stream size, morphology and chemical water characteristics for the distribution of water-dependent terrestrial habitat types, i.e. alkaline fens, periodically inundated meadows and meadows in riparian areas in Denmark using an extensive data set covering a total of 254 stream reaches. A species...

  10. Elevated stream inorganic nitrogen impacts on a dominant riparian tree species: Results from an experimental riparian stream system

    Science.gov (United States)

    Hultine, K. R.; Jackson, T. L.; Burtch, K. G.; Schaeffer, S. M.; Ehleringer, J. R.

    2008-12-01

    The release of inorganic nitrogen from intensive agricultural practices and urbanization has resulted in significant alterations of the aquatic nitrogen cycle in riparian ecosystems. Nevertheless, impacts of stream nitrogen inputs on the terrestrial nitrogen cycle and the water and carbon cycles are unclear. Information on terrestrial ecosystem responses to stream N loading is largely absent in part because of the difficulty in controlling for temporal and spatial variation in streamflow, geomorphology, climate, and vegetation. To address these issues, we constructed a dual-plot artificial stream riparian system within a 10-year-old plantation of a dominant riparian tree species, box elder (Acer negundo). The dual-plot design allowed for different concentrations of stream inorganic nitrogen between plots while controlling for ecohydrologic and geohydrologic variability. The system was used to investigate elevated inorganic stream nitrogen impacts on water use patterns, above-ground productivity, and leaf chemistry of streamside box elder trees over two consecutive growing seasons (2006 and 2007). One plot received inorganic soluble fertilizer that brought the NO3 concentration of stream water from 5 μmol l-1 to about 100 μmol l-1, while the second plot received no additional nitrogen. Relative stem sap flux density (Js) did not vary between plots until near the conclusion of the 2006 growing season, when trees in the fertilized plot showed a steep upswing in Js relative to trees in the control plot. Sap flux in 2007 increased consistently by 0.4% day-1 in the fertilized plot relative to the control plot over a 75-day period, before leveling off near the conclusion of the growing season. At the onset of the experiment, leaf nitrogen per unit mass and leaf nitrogen per unit area were significantly higher in the control plot, and leaf C:N ratios were lower. In 2007, however, differences in leaf chemistry disappeared, suggesting that leaf nitrogen increased in the

  11. Riparian Planting Projects Completed within Asotin Creek Watershed : 2000-2002 Asotin Creek Riparian Final Report of Accomplishments.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, B. J. (Bradley J.)

    2002-01-01

    The Asotin County Conservation District (ACCD) is the primary entity coordinating habitat projects on both private and public lands within the Asotin Creek watershed. The watershed covers approximately 325 square miles in the Blue Mountains of southeastern Washington in Water Resource Inventory Area (WRIA) 35. According to Washington Department of Fish and Wildlife's (WDFW) Priority WRIA's by ''At-Risk Stock Significance Map'', it is the highest priority WRIA in southeastern Washington. Summer steelhead, bull trout, and Snake River spring chinook salmon which are listed under the Endangered Species Act (ESA), are present in the watershed. WDFW manages it as a Wild Steelhead Reserve; no hatchery fish have been released here since 1997. The ACCD has been working with landowners, Bonneville Power Administration (BPA), Washington State Conservation Commission (WCC), Natural Resource Conservation Service (NRCS), Washington Department of Fish and Wildlife (WDFW), U.S. Forest Service, Pomeroy Ranger District (USFS), Nez Perce Tribe, Washington Department of Ecology (DOE), National Marine Fisheries Service (NMFS), and U.S. Fish and Wildlife Service (USFWS) to address habitat projects in Asotin County. Local students, volunteers and Salmon Corps members from the Nez Perce Tribe have been instrumental in the success of the Model Watershed Program on Asotin Creek. ACCD began coordinating habitat projects in 1995 with the help of BPA funding. Approximately two hundred and seventy-six projects have been implemented as of 1999. The Washington State Legislature was successful in securing funding for threatened and endangered salmon and steelhead recovery throughout the State in 1998. While these issues were new to most of the State, the ACCD has been securing and administering funding for threatened salmonids since 1994. The Asotin Creek Riparian Planting 2000-053-00 and Asotin Creek Riparian Fencing 2000-054-00 teamed BPA and the Governor

  12. Effects of river restoration on riparian biodiversity in secondary channels of the Pite River, Sweden.

    Science.gov (United States)

    Helfield, James M; Engström, Johanna; Michel, James T; Nilsson, Christer; Jansson, Roland

    2012-01-01

    Between 1850 and 1970, rivers throughout Sweden were channelized to facilitate timber floating. Floatway structures were installed to streamline banks and disconnect flow to secondary channels, resulting in simplified channel morphologies and more homogenous flow regimes. In recent years, local authorities have begun to restore channelized rivers. In this study, we examined the effects of restoration on riparian plant communities at previously disconnected secondary channels of the Pite River. We detected no increase in riparian diversity at restored sites relative to unrestored (i.e., disconnected) sites, but we did observe significant differences in species composition of both vascular plant and bryophyte communities. Disconnected sites featured greater zonation, with mesic-hydric floodplain species represented in plots closest to the stream and mesic-xeric upland species represented in plots farthest from the stream. In contrast, restored sites were most strongly represented by upland species at all distances relative to the stream. These patterns likely result from the increased water levels in reconnected channels where, prior to restoration, upland plants had expanded toward the stream. Nonetheless, the restored fluvial regime has not brought about the development of characteristic flood-adapted plant communities, probably due to the short time interval (ca. 5 years) since restoration. Previous studies have demonstrated relatively quick responses to similar restoration in single-channel tributaries, but secondary channels may respond differently due to the more buffered hydrologic regimes typically seen in anabranching systems. These findings illustrate how restoration outcomes can vary according to hydrologic, climatic and ecological factors, reinforcing the need for site-specific restoration strategies. PMID:22042408

  13. Restoring environmental flows and improving riparian ecosystem of Tarim River

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Rapid population growth and artificial oasis enlargement did pose great threat to the natural riparian ecosystems of Tarim River and caused seriously ecological deterioration and greater desertification of the Tarim River Basin in the second half of 20 century. Restoration of the endangered riparian ecosystem requires that environmental flow should be restored through restricted and uncontrolled flow diversion irrigation in tributary areas. Implementation of such restriction needs further the basin-wide reallocation of water resources through a set of engineering and non-engineering measures taken to ensure the water requirement in the tributary and maintain effective flows in Tarim River. As one of evolving HELP (Hydrology for Environment, Life and Policy) basins, the article first presents an overview of hydrology, socio-economic development and ecosystem evolution of the Tarim River Basin. Then, those measures for restoring and maintaining environmental flow are reviewed and analyzed along with its applicability and validity. The issues emerging in implementing those measures are also explored, and then the conclusions were summarized. Lessons learned could provide a good example for other basins under similar conditions.

  14. Ecological Impact of LAN: San Pedro Riparian National Conservation Area

    Science.gov (United States)

    Craine, Eric Richard; Craine, Brian L.

    2015-08-01

    The San Pedro River in Southeastern Arizona is home to nearly 45% of the 900 total species of birds in the United States; millions of songbirds migrate though this unique flyway every year. As the last undammed river in the Southwest, it has been called one of the “last great places” in the US. Human activity has had striking and highly visible impacts on the San Pedro River. As a result, and to help preserve and conserve the area, much of the region has been designated the San Pedro Riparian National Conservation Area (SPRNCA). Attention has been directed to impacts of population, water depletion, and border fence barriers on the riparian environment. To date, there has been little recognition that light at night (LAN), evolving with the increased local population, could have moderating influences on the area. STEM Laboratory has pioneered techniques of coordinated airborne and ground based measurements of light at night, and has undertaken a program of characterizing LAN in this region. We conducted the first aerial baseline surveys of sky brightness in 2012. Geographic Information Systems (GIS) shapefiles allow comparison and correlation of various biological databases with the LAN data. The goal is to better understand how increased dissemination of night time lighting impacts the distributions, behavior, and life cycles of biota on this ecosystem. We discuss the baseline measurements, current data collection programs, and some of the implications for specific biological systems.

  15. The signature of randomness in riparian plant root distributions

    Science.gov (United States)

    Tron, Stefania; Perona, Paolo; Gorla, Lorenzo; Schwarz, Massimiliano; Laio, Francesco; Ridolfi, Luca

    2015-09-01

    Known as "the hidden half", plant roots are fundamental contributors to the riparian ecosystem functioning. Roots show an extraordinary architectural complexity that recalls their remarkable ability to adapt to environmental heterogeneity, resources availability, and climate. In fluvial environments, phreatophytes and hydrophytes cope with flow and sediment processes, and hydrotropism and aerotropism are the main drivers for root growth. In this work, we show how the vertical root density distribution in riparian plants is the result of how plants respond to the random fluctuations of river flows. A root data set from field and controlled outdoor experiments is used in combination with a physically based analytical model to demonstrate that the root vertical density distribution can be ascribed to the interplay of randomness and determinism in a simple mathematical form. The shape of the distribution reflects the profitability of plant roots to grow in different soil layers depending on the soil moisture availability. For the first time, this model helps understanding in an analytical manner the adaptation strategy of plant roots to different scenarios, paving the way for the comprehension of the effects of future changes in climate and environmental conditions.

  16. The Riparian Alder Forests of the Sopron Hills

    Directory of Open Access Journals (Sweden)

    SZMORAD, Ferenc

    2011-01-01

    Full Text Available The present study demonstrates the classification of the riparian alder forests of theAlpokalja region through the analysis of their stands in the Sopron Hills. Besides the historical,ecological and floristic data collection, the differentiation of these forests was examined using36 coenological relevés recorded according to the Braun-Blanquet method. Cluster analysis,principal component analysis and TWINSPAN analysis were applied in the process; the definitionof diagnostic species for the resulting units was carried out by fidelity analysis using the coefficient. The presence of three alder forest associations was verified by the research in thestudy area. In the vicinity of the lower and middle sections of the streams, characterized bystagnant water, small patches of swampy alder forests (Angelico sylvestris – Alnetum glutinosaeoccur. In the fast-flowing stream sections alder woods rich in species of mesophilic deciduousforests (Aegopodio – Alnetum glutinosae can be found, while along the middle and upper sectionsof the streams, at sites with seepage water, mixed ash-alder forests with montane herb species(Carici remotae – Fraxinetum are typical. The investigations revealed that the Carex brizoidesdominance-type alder groves were secondary forests that formed in former meadows and theybelong to the 3 mentioned riparian alder forest types.

  17. Bringing light to remnants of riparian areas in rice field channels: a combined application of linear transects and the mapping method

    OpenAIRE

    Godinho, Carlos; Pereira, Pedro; Rabaça, João E.

    2010-01-01

    The importance of rice fields for bird conservation has been subject of several studies, mainly focused in core areas as habitat for waterbirds. However, significant parts of the rice field structure, like the irrigation channels that control the water level, are often neglected. These corridor-like areas are frequently characterized by the presence of riparian vegetation like willows and ashes or wetland vegetation like reedmace or common reedbeds. In order to assess the importance of these ...

  18. Arthropod prey for riparian associated birds in headwater forests of the Oregon Coast Range

    Science.gov (United States)

    Hagar, Joan C.; Li, Judith; Sobota, Janel; Jenkins, Stephanie

    2012-01-01

    Headwater riparian areas occupy a large proportion of the land base in Pacific Northwest forests, and thus are ecologically and economically important. Although a primary goal of management along small headwater streams is the protection of aquatic resources, streamside habitat also is important for many terrestrial wildlife species. However, mechanisms underlying the riparian associations of some terrestrial species have not been well studied, particularly for headwater drainages. We investigated the diets of and food availability for four bird species associated with riparian habitats in montane coastal forests of western Oregon, USA. We examined variation in the availability of arthropod prey as a function of distance from stream. Specifically, we tested the hypotheses that (1) emergent aquatic insects were a food source for insectivorous birds in headwater riparian areas, and (2) the abundances of aquatic and terrestrial arthropod prey did not differ between streamside and upland areas during the bird breeding season. We found that although adult aquatic insects were available for consumption throughout the study period, they represented a relatively small proportion of available prey abundance and biomass and were present in only 1% of the diet samples from only one of the four riparian-associated bird species. Nonetheless, arthropod prey, comprised primarily of insects of terrestrial origin, was more abundant in streamside than upland samples. We conclude that food resources for birds in headwater riparian areas are primarily associated with terrestrial vegetation, and that bird distributions along the gradient from streamside to upland may be related to variation in arthropod prey availability. Because distinct vegetation may distinguish riparian from upland habitats for riparian-associated birds and their terrestrial arthropod prey, we suggest that understory communities be considered when defining management zones for riparian habitat.

  19. Examining Riparian Drinking Water Resources in the Danube Basin

    International Nuclear Information System (INIS)

    The importance of the need for high quality drinking water and for its long term secure supply is growing, even in economically medium developed countries. The drinking water requirements of several million people are covered by bank filtered (riparian) groundwater resources along the Danube River and its tributaries. These are very vulnerable water resources, of which exploited water is a mixture of waters coming from a minimum of two, but often from three or four sources as river water, locally infiltrated precipitation, distantly infiltrated precipitation, or infiltrated still water (from lakes or wetlands). The European Union (EU) Water Framework Directive (WFD) requires the setup of protected areas and management plans for groundwater bodies based on conceptual hydrological models. One of the most reliable methods for proving, calibrating or verifying these models is the application of environmental isotope data

  20. Dioecy Impacts on Plant Water Fluxes in Riparian Ecosystems

    Science.gov (United States)

    Hultine, K. R.; Bush, S. E.; West, A. G.; Ehleringer, J. R.

    2005-12-01

    Dioecious plants are frequently associated with different spatial distributions of the two sexes across resource gradients. Segregation between sexes might be expected to occur if the cost of reproduction is greater in females than in males. If so, females would be under stronger selection to increase rates of resource uptake. Acer negundo is a dioecious riparian tree species that show spatial segregation among sexes: females are typically more common along streamside (high resource) environments than males. The spatial segregation of the sexes leads to the hypothesis that male and female individuals have varying influence on ecohydrological processes. To address this, we measured sap flux, water relations and hydraulic architecture of mature streamside (less than 1 m from stream channel) male and female Acer negundo trees occurring near Salt Lake City, Utah, USA during the 2004 growing season. Despite similar predawn and midday leaf water potentials, sap flux density ( Js) was 40 percent higher in female trees than in male trees during the 2004 growing season (n = 42 days, F = 73.56, P genders showed a similar relationship between conducting sapwood area to stem diameter ratio suggesting that differences in Js scale to the whole tree level. Sap flux data from Acer negundo trees was compared to five other co-occurring riparian tree species. Female Acer negundo trees showed the highest Js among all species while Js in male Acer negundo trees was lower than all other species except one ( Acer grandidentatum). These data demonstrate that individual female Acer negundo trees have the capacity remove water at higher rates than males in high resource environments. The spatial segregation of the sexes along streamside environments may therefore have profound impacts on ecohydrological processes such as stream discharge, groundwater recharge, and nutrient cycling.

  1. DEVELOPMENT OF AN INDEX OF ALIEN SPECIES INVASIVENESS: AN AID TO ASSESSING RIPARIAN VEGETATION CONDITION

    Science.gov (United States)

    Many riparian areas are invaded by alien plant species that negatively affect native species composition, community dynamics and ecosystem properties. We sampled vegetation along reaches of 31 low order streams in eastern Oregon, and characterized species assemblages at patch an...

  2. RELATIONSHIPS OF ALIEN PLANT SPECIES ABUNDANCE TO RIPARIAN VEGETATION, ENVIRONMENT, AND DISTURBANCE

    Science.gov (United States)

    Riparian ecosystems are often invaded by alien species. We evaluated vegetation, environment, and disturbance conditions and their interrelationships with alien species abundance along reaches of 29 streams in eastern Oregon, USA. Using flexible-BETA clustering, indicator species...

  3. EnviroAtlas - Fresno, CA - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  4. EnviroAtlas - New Bedford, MA - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  5. EnviroAtlas - New York, NY - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. In this community, forest is defined as Trees & Forest. There is a...

  6. EnviroAtlas - Woodbine, Iowa - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  7. EnviroAtlas - Portland, OR - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  8. EnviroAtlas - Green Bay, WI - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  9. EnviroAtlas - Phoenix, AZ - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  10. EnviroAtlas - New York, NY - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. In this community, vegetated cover is defined as Trees & Forest...

  11. EnviroAtlas - Milwaukee, WI - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  12. EnviroAtlas - Pittsburgh, PA - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  13. EnviroAtlas - Phoenix, AZ - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  14. EnviroAtlas - Paterson, NJ - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  15. EnviroAtlas - Woodbine, IA - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  16. EnviroAtlas - Milwaukee, WI - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  17. EnviroAtlas - Pittsburgh, PA - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  18. EnviroAtlas - Paterson, NJ - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  19. EnviroAtlas - New Bedford, MA - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  20. EnviroAtlas - Paterson, NJ - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  1. EnviroAtlas - Green Bay, WI - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  2. EnviroAtlas - Fresno, CA - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  3. EnviroAtlas - Phoenix, AZ - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  4. EnviroAtlas - New York, NY - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. In this community, vegetated cover is defined as Trees & Forest...

  5. EnviroAtlas - Green Bay, WI - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  6. EnviroAtlas - Pittsburgh, PA - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  7. EnviroAtlas - Phoenix, AZ - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  8. EnviroAtlas - Portland, ME - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  9. EnviroAtlas - Tampa, FL - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  10. EnviroAtlas - Portland, OR - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  11. EnviroAtlas - Portland, ME - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  12. EnviroAtlas - Woodbine, IA - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  13. EnviroAtlas - Milwaukee, WI - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  14. EnviroAtlas - Woodbine, IA - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  15. EnviroAtlas - Memphis, TN - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. Forest is defined as Trees & Forest and Woody Wetlands. There is a...

  16. EnviroAtlas - Fresno, CA - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  17. EnviroAtlas - Tampa, FL - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  18. EnviroAtlas - Green Bay, WI - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  19. EnviroAtlas - Tampa, FL - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  20. EnviroAtlas - Milwaukee, WI - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  1. EnviroAtlas - Fresno, CA - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  2. Riparian Land-Use and Rehabilitation: Impact on Organic Matter Input and Soil Respiration

    Science.gov (United States)

    Oelbermann, Maren; Raimbault, Beverly A.

    2015-02-01

    Rehabilitated riparian zones in agricultural landscapes enhance environmental integrity and provide environmental services such as carbon (C) sequestration. This study quantified differences in organic matter input, soil biochemical characteristics, and soil respiration in a 25-year-old rehabilitated (RH), grass (GRS), and undisturbed natural forest (UNF) riparian zone. Input from herbaceous vegetation was significantly greater ( P land-use systems. Rehabilitating degraded riparian zones with trees rather than GRS is a more effective approach to the long-term mitigation of CO2. Therefore, the protection of existing natural/undisturbed riparian forests in agricultural landscapes is equally important as their rehabilitation with trees, given their higher levels of soil organic C and lower soil respiration rates.

  3. Spatial Characterization of Riparian Buffer Effects on Sediment Loads from Watershed Systems

    Science.gov (United States)

    Understanding all watershed systems and their interactions is a complex, but critical, undertaking when developing practices designed to reduce topsoil loss and chemical/nutrient transport from agricultural fields. The presence of riparian buffer vegetation in agricultural lands...

  4. Estimating evapotranspiration under warmer climates: Insights from a semiarid riparian system

    Science.gov (United States)

    This paper presents an approach to quantify evapotranspiration under changing climates, using field observations, theoretical evaporation models and meteorological predictions from global climate models. We analyzed evaporation and meteorological data from three riparian sites located in a semiarid ...

  5. Dendroclimatic signals deduced from riparian versus upland forest interior pines in North Karelia, Finland

    DEFF Research Database (Denmark)

    Helama, Samuli; Arentoft, Birgitte W.; Collin-Haubensak, Olivier; Hyslop, Michael D.; Brandstrup, Charlotte K.; Makela, Hanna M.; Tian, QinHua; Wilson, Rob

    2013-01-01

    Radial growth of boreal tree species is only rarely studied in riparian habitats. Here we investigated chronologies of earlywood, latewood, and annual ring widths and blue intensity (BI; a surrogate to latewood density) from riparian lake shore and upland forest interior pines (Pinus sylvestris L.......) growing in boreal forest in eastern Finland. Riparian and upland chronologies were compared to examine differences in the pine growth variability and growth response to climatic variation in the two habitats. It was found that the climatic variables showing statistically significant correlations with the...... tree-ring chronologies were related to snow conditions at the start of the growing season. Deeper snowpack led to reduced upland pine growth, possibly due to delayed snowmelt and thus postponed onset of the growing season. Warm late winters were followed by increased riparian pine growth because of...

  6. EnviroAtlas - New Bedford, MA - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  7. EnviroAtlas - Memphis, TN - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. Forest is defined as Trees & Forest and Woody Wetlands. There is a...

  8. EnviroAtlas - Pittsburgh, PA - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  9. EnviroAtlas - Portland, Maine - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  10. EnviroAtlas - Paterson, NJ - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  11. EnviroAtlas - Portland, OR - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  12. Arapaho National Wildlife Refuge and the Owl Moutain Partnership riparian/meadow management demonstration project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Arapaho National Wildlife Refuge (Refuge) and the Owl Mountain Partnership (OMP) are implementing a 5-year riparian/meadow management demonstration project. The...

  13. EnviroAtlas - Durham, NC - 51m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is forested. There is a potential for decreased water quality in areas where the...

  14. EnviroAtlas - Tampa, FL - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  15. EnviroAtlas - Durham, NC - 15m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  16. EnviroAtlas - New York, NY - 15m Riparian Buffer Forest Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 15-m riparian buffer that is forested. In this community, forest is defined as Trees & Forest. There is a...

  17. EnviroAtlas - Portland, ME - 51m Riparian Buffer Vegetated Cover

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the percentage of a 51-m riparian buffer that is vegetated. There is a potential for decreased water quality in areas where the...

  18. Hot spots and hot moments in riparian zones: potential for improved water quality management

    Science.gov (United States)

    Despite considerable heterogeneity over space and time, biogeochemical and hydrological processes in riparian zones regulate contaminant movement to receiving waters and often mitigate the impact of upland sources of contaminants on water quality. Recently, these heterogeneous processes have been co...

  19. Predicting the impact of water demand and river flow regulation over riparian vegetation through mathematical modeling

    Science.gov (United States)

    Garcia-Arias, A.; Pons, C.; Frances, F.

    2013-12-01

    The vegetation of the riversides is a main part of the complex riparian ecosystems and has an important role maintaining the fluvial ecosystems. Biotic and abiotic interactions between the river and the riverbank are essential for the subsistence and the development of both ecosystems. In semi-arid Mediterranean areas, the riparian vegetation growth and distribution is especially controlled by the water accessibility, determining the limit between the lush riparian bands and the sparse upland. Human intervention can alter the river hydrology determining the riparian vegetation wellbeing and its distribution and, in consequence, affecting both riparian and fluvial ecosystems. Predictive models are necessary decision support tools for adequate river management and restoration initiatives. In this context, the RibAV model is useful to predict the impact of water demand and river flow regulation on the riparian vegetation. RibAV is able to reproduce the vegetation performance on the riverside allowing the scenarios analysis in terms of vegetation distribution and wellbeing. In this research several flow regulation and water demand scenarios are proposed and the impacts over three plant functional types (PFTs) are analyzed. The PFTs group the herbaceous riparian plants, the woody riparian plants and the terrestrial vegetation. The study site is the Terde reach at the Mijares River, a 539m length reach located in a semi-arid Mediterranean area in Spain. The scenarios represent river flow alterations required to attend different human demands. These demands encompass different seasonality, magnitude and location. The seasonality is represented as hydroelectric (constant all over the year), urban (increased during the summer period) and agricultural demands (monthly seasonality). The magnitude is varied considering the 20%, the 40% and the 80% of the mean daily flow. Two locations are considered, upstream or downstream the study site. To attend the demands located

  20. Importance of riparian remnants for frog species diversity in a highly fragmented rainforest

    OpenAIRE

    Rodríguez-Mendoza, Clara; Pineda, Eduardo

    2010-01-01

    Tropical forests undergo continuous transformation to other land uses, resulting in landscapes typified by forest fragments surrounded by anthropogenic habitats. Small forest fragments, specifically strip-shaped remnants flanking streams (referred to as riparian remnants), can be particularly important for the maintenance and conservation of biodiversity within highly fragmented forests. We compared frog species diversity between riparian remnants, other forest fragments and cattle pastures i...

  1. Restoration or Disturbance: Assessing the Impacts of a Salmon Habitat Restoration Project on Riparian Vegetation Composition

    OpenAIRE

    Azevedo, Andhra; Chin, Larissa; Dullemond, Kia; Morton, Lovena; Naghshinepour, Negar; Salihue, Hafsa

    2013-01-01

    Invasive plant species can threaten the biodiversity and resilience of riparian ecosystems. A vegetation assessment of the riparian zone beside the Stoney Creek Off-Channel Habitat Project compared with a non-restored site and a previously replanted site showed that the sites were significantly different in their vegetation composition. All three sites had several invasive species of concern playing dominant roles in the ecosystem with the most common two species being English ivy (Hedera hel...

  2. Long-term effects of riparian-plant diversity loss on a stream invertebrate shredder

    OpenAIRE

    Fernandes, Isabel Rodrigues; Duarte, Sofia; Pascoal, Cláudia; Cássio, Fernanda

    2012-01-01

    We used a pool of 3 common riparian-plant species in Portugal (alder, oak and eucalyptus) to examine the potential long-term impacts of riparian diversity loss on the feeding behaviour and body composition of a stream invertebrate shredder (Limnephilidae). Fine-mesh bags containing mixtures of the 3 leaf species were immersed in a mixed-forested stream to allow microbial colonization. After 2 weeks, colonized leaves were transferred to microcosms contain...

  3. Eutrophication alters the effects of riparian plant diversity on litter decomposition by macroinvertebrates

    OpenAIRE

    Fernandes, Eva Lima

    2011-01-01

    Dissertação de mestrado em Ecology In low-order forested streams, plant-litter decomposition is a key ecosystem process. Invertebrate shredders are responsible for the breakdown of plant litter and are very sensitive to stream water quality degradation. Increased eutrophication and loss or alteration of riparian vegetation can have negative effects on stream organisms and alter ecosystem processes. However, the interactive effects of riparian vegetation loss and increased nu...

  4. Early Response of Soil Properties and Function to Riparian Rainforest Restoration

    OpenAIRE

    Gageler, Rose; Bonner, Mark; Kirchhof, Gunnar; Amos, Mark; Robinson, Nicole; Schmidt, Susanne; Shoo, Luke P.

    2014-01-01

    Reforestation of riparian zones is increasingly practiced in many regions for purposes of biodiversity conservation, bank stabilisation, and improvement in water quality. This is in spite of the actual benefits of reforestation for recovering underlying soil properties and function remaining poorly understood. Here we compare remnant riparian rainforest, pasture and reforestation plantings aged 2–20 years in an Australian subtropical catchment on ferrosols to determine the extent to which ref...

  5. Linking soil- and stream-water chemistry based on a Riparian Flow-Concentration Integration Model

    OpenAIRE

    J. Seibert; T. Grabs; Köhler, S; H. Laudon; Winterdahl, M.; Bishop, K.

    2009-01-01

    The riparian zone, the last few metres of soil through which water flows before entering a gaining stream, has been identified as a first order control on key aspects of stream water chemistry dynamics. We propose that the distribution of lateral flow of water across the vertical profile of soil water chemistry in the riparian zone provides a conceptual explanation of how this control functions in catchments where matrix flow predominates. This paper presents a mathematical implementation of ...

  6. Riparian plant community responses to increased flooding: a meta-analysis.

    Science.gov (United States)

    Garssen, Annemarie G; Baattrup-Pedersen, Annette; Voesenek, Laurentius A C J; Verhoeven, Jos T A; Soons, Merel B

    2015-08-01

    A future higher risk of severe flooding of streams and rivers has been projected to change riparian plant community composition and species richness, but the extent and direction of the expected change remain uncertain. We conducted a meta-analysis to synthesize globally available experimental evidence and assess the effects of increased flooding on (1) riparian adult plant and seedling survival, (2) riparian plant biomass and (3) riparian plant species composition and richness. We evaluated which plant traits are of key importance for the response of riparian plant species to flooding. We identified and analysed 53 papers from ISI Web of Knowledge which presented quantitative experimental results on flooding treatments and corresponding control situations. Our meta-analysis demonstrated how longer duration of flooding, greater depth of flooding and, particularly, their combination reduce seedling survival of most riparian species. Plant height above water level, ability to elongate shoots and plasticity in root porosity were decisive for adult plant survival and growth during longer periods of flooding. Both 'quiescence' and 'escape' proved to be successful strategies promoting riparian plant survival, which was reflected in the wide variation in survival (full range between 0 and 100%) under fully submerged conditions, while plants that protrude above the water level (>20 cm) almost all survive. Our survey confirmed that the projected increase in the duration and depth of flooding periods is sufficient to result in species shifts. These shifts may lead to increased or decreased riparian species richness depending on the nutrient, climatic and hydrological status of the catchment. Species richness was generally reduced at flooded sites in nutrient-rich catchments and sites that previously experienced relatively stable hydrographs (e.g. rain-fed lowland streams). Species richness usually increased at sites in desert and semi-arid climate regions (e.g. intermittent

  7. Soil organic carbon in riparian forests, rice fields, and pastures in Piedras, Tolima, Colombia.

    Directory of Open Access Journals (Sweden)

    Hernán Jair Andrade-Castañeda

    2016-06-01

    Full Text Available The aim of the study was to estimate the soil organic carbon (SOC storage in the interface between riparian forests and a matrix of rice fields and pastures with organic management. The study took place in Piedras, Tolima, Colombia. Two plots in production (rice and pasture were selected and SOC was estimated in these areas and in the edge and the interior of adjacent riparian forests at a depth of 0 to 20 cm. Bulk density and SOC concentration were quantified between May and July, 2013. Potential change in SOC storage due to land use change among rice fields, pastures, and riparian forests was estimated. The interfaces rice field-riparian forest and pasture-riparian forest stored an average of 65.6 and 61.3 t C/ha, respectively, with no statistical differences (p>0.05. Statistical differences were not detected (p>0.05 between agricultural matrices (rice fields and pastures in any of the variables. The sampling position (matrix and the edge and interior of forests had a significant impact (p<0.05 just in bulk density: 1.7 vs 1.1 vs 1.0 g/cm3 in interior and edge of the riparian forests and the matrix, respectively. SOC was not statistically affected (p>0.05 by the position in the riparian forest-matrix interface. Conversion from riparian forests to rice fields or pastures with organic management is not emitting greenhouse gases, on the contrary, it is increasing SOC in 3.2 t C/ha. 

  8. Litter Controls Earthworm-Mediated Carbon and Nitrogen Transformations in Soil from Temperate Riparian Buffers

    OpenAIRE

    2014-01-01

    Nutrient cycling in riparian buffers is partly influenced by decomposition of crop, grass, and native tree species litter. Nonnative earthworms in riparian soils in southern Quebec are expected to speed the processes of litter decomposition and nitrogen (N) mineralization, increasing carbon (C) and N losses in gaseous forms or via leachate. A 5-month microcosm experiment evaluated the effect of Aporrectodea turgida on the decomposition of 3 litter types (deciduous leaves, reed canarygrass, an...

  9. Responses of Mediterranean aquatic and riparian communities to human pressures at different spatial scales

    OpenAIRE

    Bruno, D.; Belmar, O.; D. Sánchez-Fernández; S. Guareschi; Millán, A.; Velasco, J

    2014-01-01

    Mediterranean river ecosystems are subjected to intense human pressures and impacts that affect both their aquatic and riparian communities. However, given their stratified position in the river ecosystem and varying ecological requirements, aquatic and riparian communities can respond differently to such pressures. These biological responses could also vary depending on the nature of the disturbances, the spatial scale considered and the indicators used as response variable. Here, we aim to ...

  10. An assessment of riparian environmental quality by using butterflies and disturbance susceptibility scores

    Science.gov (United States)

    Nelson, S. Mark; Andersen, Douglas C.

    1994-01-01

    The butterfly community at a revegetated riparian site on the lower Colorado River near Parker, Arizona, was compared to that found in a reference riparian site. Data indicated that the herbaceous plant community, which was lacking at the revegetated site, was important to several butterfly taxa. An index using butterfly sensitivity to habitat change (species classified into risk groups) and number of taxa was developed to monitor revegetation projects and to determine restoration effectiveness.

  11. Near-Term Effects of Repeated-Thinning with Riparian Buffers on Headwater Stream Vertebrates and Habitats in Oregon, USA

    Directory of Open Access Journals (Sweden)

    Deanna H. Olson

    2014-11-01

    Full Text Available We examined the effects of a second-thinning harvest with alternative riparian buffer management approaches on headwater stream habitats and associated vertebrates in western Oregon, USA. Our analyses showed that stream reaches were generally distinguished primarily by average width and depth, along with the percentage of the dry reach length, and secondarily, by the volume of down wood. In the first year post-harvest, we observed no effects of buffer treatment on stream habitat attributes after moderate levels of thinning. One of two “thin-through” riparian treatments showed stronger trends for enlarged stream channels, likely due to harvest disturbances. The effects of buffer treatments on salamanders varied among species and with habitat structure. Densities of Plethodon dunni and Rhyacotriton species increased post-harvest in the moderate-density thinning with no-entry buffers in wider streams with more pools and narrower streams with more down wood, respectively. However, Rhyacotriton densities decreased along streams with the narrowest buffer, 6 m, and P. dunni and Dicamptodon tenebrosus densities decreased in thin-through buffers. Our study supports the use of a 15-m or wider buffer to retain sensitive headwater stream amphibians.

  12. Gram-Positive Nickel Resistant Bacteria Isolated from Riparian Sediments Contaminated with Ni and U on the Savannah River Site

    Science.gov (United States)

    Sowder, A. G.; Khijniak, T. V.; van Nostrand, J.; Bertsch, P. M.; Morris, P. J.

    2002-12-01

    The natural attenuation of pollutants in riparian and wetland systems is driven in large part by the services provided by the diverse microbial communities that thrive in these nutritionally and chemically complex environments. For co-contaminated systems, the presence of heavy metals at excessive levels may alter the structure and function of microbial communities that are essential for the immobilization of inorganics and degradation of organic contaminants. We examined riparian sediments heavily contaminated with U and Ni (1000's of mg/kg) from a small stream on the U.S. Department of Energy's Savannah River Site that received metallurgical process effluents wastewater over a thirty-year period associated with the production of nuclear materials. Four gram positive bacteria were isolated that displayed marked resistance (5000 mg/kg) to Ni relative to organisms from uncontaminated control locations: Arthrobacter oxydans, Streptomyces galbus, Streptomyces aureofaciens, and Kitasatospora cystarginea. The metal resistance of S. aureofaciens and K. cystarginea was further characterized in growth experiments for resistance to other metals. Ongoing geochemical characterization of U and Ni in terms of solid phase partitioning and aqueous phase speciation and solubility indicate that Ni is more chemically labile and, by extension, bioavailable than U in these aged-contaminated sediments. Accordingly, the isolation of Ni resistant organisms is consistent with greater selective pressure from Ni as a result of its greater bioavailability. These results are placed in context of environmental management and remediation of co-contaminated, biogeochemically complex environments.

  13. Distribution pattern of rare plants along riparian zone in Shennongjia Area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Due to the importance of riparian zone in maintaining and protecting regional biodiversity, increasingly more ecologists paid their attentions to riparian zone and had been aware of the important effects of riparian zone in basic study and practical management. In this study, 42 sampling belts (10 m×100 m) parallel to the bank of Xiangxi River at different elevations in Shennongjia Area were selected to investigate the riparian vegetation and rare plants. 14 species of rare plants were found distributing in riparian zone, accounting for 42.4% of the total rare plant species in Shennongjia Area. The main distribution range of the 14 rare plant species was the evergreen and deciduous mixed broadleaved forest at elevation of 1200-1800 m, where, species diversity of plant community was the maximum at the moderate elevation. The analysis of TWINSPAN divided the 14 rare species into 3 groups against the elevation, namely low elevation species group, moderate elevation species group, and high elevation species group. The analysis of DCA ordination showed similar results to that of TWINSPAN. In the paper, the authors discussed the reasons forming the distribution pattern of rare plant species, and pointed out that the important function of riparian zone on rare plant species protection.

  14. Water quality dynamics and hydrology in nitrate loaded riparian zones in Netherlands

    International Nuclear Information System (INIS)

    Riparian zones are known to function as buffers, reducing non-point source pollution from agricultural land to streams. In Netherlands, riparian zones are subject to high nitrogen inputs. We combined hydrological, chemical and soil profile data with groundwater modelling to evaluate whether chronically N loaded riparian zones were still mitigating diffuse nitrate fluxes. Hydraulic parameters and water quality were monitored over 2 years in 50 piezometres in a forested and grassland riparian zone. Average nitrate loadings were high in the forested zone with 87 g NO3--N m-2 y-1 and significantly lower in the grassland zone with 15 g NO3--N m-2 y-1. Groundwater from a second aquifer diluted the nitrate loaded agricultural runoff. Biological N removal however occurred in both riparian zones, the grassland zone removed about 63% of the incoming nitrate load, whereas in the forested zone clear symptoms of saturation were visible and only 38% of the nitrate load was removed. - Riparian zones reduced nitrate from agricultural lands

  15. Water sources and mixing in riparian wetlands revealed by tracers and geospatial analysis

    Science.gov (United States)

    Lessels, Jason S.; Tetzlaff, Doerthe; Birkel, Christian; Dick, Jonathan; Soulsby, Chris

    2016-01-01

    Mixing of waters within riparian zones has been identified as an important influence on runoff generation and water quality. Improved understanding of the controls on the spatial and temporal variability of water sources and how they mix in riparian zones is therefore of both fundamental and applied interest. In this study, we have combined topographic indices derived from a high-resolution Digital Elevation Model (DEM) with repeated spatially high-resolution synoptic sampling of multiple tracers to investigate such dynamics of source water mixing. We use geostatistics to estimate concentrations of three different tracers (deuterium, alkalinity, and dissolved organic carbon) across an extended riparian zone in a headwater catchment in NE Scotland, to identify spatial and temporal influences on mixing of source waters. The various biogeochemical tracers and stable isotopes helped constrain the sources of runoff and their temporal dynamics. Results show that spatial variability in all three tracers was evident in all sampling campaigns, but more pronounced in warmer dryer periods. The extent of mixing areas within the riparian area reflected strong hydroclimatic controls and showed large degrees of expansion and contraction that was not strongly related to topographic indices. The integrated approach of using multiple tracers, geospatial statistics, and topographic analysis allowed us to classify three main riparian source areas and mixing zones. This study underlines the importance of the riparian zones for mixing soil water and groundwater and introduces a novel approach how this mixing can be quantified and the effect on the downstream chemistry be assessed.

  16. Bioavailability and diagenetic state of dissolved organic matter in riparian groundwater

    Science.gov (United States)

    Peter, Simone; Shen, Yuan; Kaiser, Karl; Benner, Ronald; Durisch-Kaiser, Edith

    2012-12-01

    Riparian groundwater can exhibit considerable patchiness in the concentration and reactivity of dissolved organic matter (DOM), which ultimately shapes subsurface biogeochemical transformations. Free and combined amino acids are bioavailable constituents of DOM, and their concentration and composition can provide valuable information about the diagenetic state of DOM. Based on riparian groundwater samples and relevant DOM end-member samples, we adapted the amino-acid-based marine DOM degradation index (DI) to groundwater. The groundwater DI was applied to evaluate the spatial and temporal variability in the bioavailability and diagenetic state of riparian DOM in a restored and a channelized section of the River Thur, Switzerland. Among different indicators for DOM diagenetic state (total hydrolysable amino acid concentrations, C-normalized yields, and the contribution of nonprotein amino acids), the groundwater DI correlated best with the activity of the enzyme leucine-aminopeptidase and bacterial secondary production in riparian groundwater. The "freshest" DOM was consistently found in the channel and during high-flow conditions in the groundwater of the restored riparian section and was spatially constrained to a zone inhabited by a dense willow population. The use of amino acid data and the newly developed DI for DOM in groundwater is a promising approach for characterizing the spatial and temporal dynamics of DOM reactivity and diagenesis within riparian groundwater.

  17. Water sources accessed by arid zone riparian trees in highly saline environments, Australia.

    Science.gov (United States)

    Costelloe, Justin F; Payne, Emily; Woodrow, Ian E; Irvine, Elizabeth C; Western, Andrew W; Leaney, Fred W

    2008-05-01

    The flow regimes of arid zone rivers are often highly variable, and shallow groundwater in the alluvial aquifers can be very saline, thus constraining the availability and quality of the major water sources available to riparian trees-soil water, shallow groundwater and stream water. We have identified water sources and strategies used by riparian trees in more highly saline and arid conditions than previously studied for riparian trees of arid zone rivers. Our research focused on the riparian species Eucalyptus coolabah, one of the major riparian trees of ephemeral arid zone rivers in Australia. The water sources available to this riparian tree were examined using delta(18)O isotope data from xylem, soil water, groundwater and surface water. Additionally, soil chloride and matric potential data were used to infer zones of water availability for root uptake. Despite the saline conditions, the trees used a mixture of soil water and groundwater sources, but they did not use surface water directly. The study identified three strategies used to cope with typically high groundwater and soil water salinities. Firstly, the trees preferentially grow in zones of most frequent flushing by infiltrating streamflow, such as the bank-tops of channels. Secondly, the trees limit water use by having low transpiration rates. Thirdly, the trees are able to extract water at very low osmotic potentials, with water uptake continuing at chloride concentrations of at least 20,000-30,000 mg L(-1). PMID:18270743

  18. Costs of Producing Biomass from Riparian Buffer Strips

    Energy Technology Data Exchange (ETDEWEB)

    Turhollow, A.

    2000-09-01

    Nutrient runoff from poultry litter applied to agricultural fields in the Delmarva Peninsula contributes to high nutrient loadings in Chesapeake Bay. One potential means of ameliorating this problem is the use of riparian buffer strips. Riparian buffer strips intercept overland flows of water, sediments, nutrients, and pollutants; and ground water flows of nutrients and pollutants. Costs are estimated for three biomass systems grown on buffer strips: willow planted at a density of 15,300 trees/ha (6200 trees/acre); poplar planted at a density of 1345 trees/ha (545 trees/acre); and switchgrass. These costs are estimated for five different scenarios: (1) total economic costs, where everything is costed [cash costs, noncash costs (e.g., depreciation), land rent, labor]; (2) costs with Conservation Reserve Program (CRP) payments (which pays 50% of establishment costs and an annual land rent); (3) costs with enhanced CRP payments (which pays 95% of establishment costs and an annual payment of approximately 170% of land rent for trees and 150% of land rent for grasses); (4) costs when buffer strips are required, but harvest of biomass is not required [costs borne by biomass are for yield enhancing activities (e.g., fertilization), harvest, and transport]; and (5) costs when buffer strips are required. and harvest of biomass is required to remove nutrients (costs borne by biomass are for yield enhancing activities and transport). CRP regulations would have to change to allow harvest. Delivered costs of willow, poplar, and switchgrass [including transportation costs of $0.38/GJ ($0.40/million Btu) for switchgrass and $0.57/GJ ($0.60/million Btu) for willow and poplar] at 11.2 dry Mg/ha-year (5 dry tons/acre-year) for the five cost scenarios listed above are [$/GJ ($million BIN)]: (1) 3.30-5.45 (3.45-5.75); (2) 2.30-3.80 (2.45-4.00); (3) 1.70-2.45 (1.80-2.60); (4) l-85-3.80 (1.95-4.05); and (5) 0.80-1.50 (0.85-1.60). At yields of 15.7 to 17.9 GJ/ha-year (7 to 8 dry tons

  19. Integration of LiDAR and QuickBird imagery for mapping riparian zones in Australian tropical savannas.

    OpenAIRE

    Arroyo Méndez, Lara Ainoa; Johansen, Kasper; Armston, John; Phinn, Stuart; Pascual Castaño, Isabel Cristina

    2008-01-01

    Riparian zones are exposed to increasing pressures because of disturbance from agricultural and urban expansion and overgrazing. Accurate and cost-effective mapping of riparian environments is important for managing their functions associated with water quality, biodiversity, and wildlife habitats. The objective of this research was to integrate Light Detection and Ranging (LiDAR) and high spatial resolution QuickBird-2 imagery to estimate riparian zone attributes. A digital terrain model (DT...

  20. Herbivore-induced "deshrubification" alters the biogeochemistry of subarctic riparian ecosystems

    Science.gov (United States)

    Smis, Adriaan; Ravolainen, Virve; Bråthen, Kari Anne; Ims, Rolf; Meire, Patrick; Struyf, Eric

    2013-04-01

    In the European subarctic, river valleys and other moist zones are dominated by tall shrub tundra, dominated by willows. Although climate warming is generally hypothesized to result in an expansion of this shrub zone, intensive reindeer husbandry in Finnmark (Northern Fennoscandia) during the last three decades seems to have resulted in a "deshrubification": riparian tall willow dominated shrub zones evolved to open meadows, dominated by grasses. These changes in land cover may have major biogeochemical consequences for both the terrestrial and aquatic environment. We investigated the relation between this "deshrubification" and the biogeochemical cycling of silicon (Si), nitrogen (N) and phosphorous (P), essential nutrients for aquatic primary production. This study was conducted along a climatic gradient from the moist and warm southwest towards the drier and colder northeast of Finnmark. Along the contrast of Finnmarks typical reindeer husbandry system, with intensively grazed summer pastures and extensively grazed spring/autumn pastures, we quantified the difference in vegetation composition and the associated differences in terrestrial pools of Si, N, P and soil organic carbon. Intensive reindeer grazing consistently excludes the presence of willow shrubs in the studied riparian zone and the transition from willow dominated tall shrub tundra towards open meadows dominated by grasses is associated with a clear silicification of the vegetation: all dominating grasses in the open meadow-state show 10 to 30 times higher Si concentrations compared to the dominating willow and forb species of the tall shrub vegetation, but also original tall shrub species show increased Si-concentrations under the intensive grazing regime. Silicon is a known defence component against herbivory, especially in grasses. Opposite, a transition to more N- and P-poor species occurs under intensive reindeer grazing: the continuum between tall willow dominated shrubs and open meadows is

  1. Comparing riparian forest processes on large rivers to inform floodplain management and restoration

    Science.gov (United States)

    Stella, J. C.; Piegay, H.; Gruel, C.; Riddle, J.; Raepple, B.

    2014-12-01

    by Acer negundo (box elder), which is non-native and invasive in Europe, suggesting similar processes of colonization and propagation in both systems. Overall, the Sacramento can serve as a predictive reference system for the Rhône, where significant restoration efforts are undeway to improve riparian structure and function in diverted river reaches.

  2. Investigation of Nitrogen Pathways in Typical Entropic-Modified Riparian Zones of the Arges River Catchment’s Area, Romania

    International Nuclear Information System (INIS)

    Surface and groundwater pollution by nutrients from agriculture is a major environmental problem in Romania. Agricultural intensification with excess use of fertilizer and pesticide, more than crop need contributed to such pollution. This pollution problem can continue into the future even if improved practices are implemented. Therefore it is necessary to find viable solutions that can be applied at large spatial scale and with relatively low costs. Use of natural areas located along the rivers and other surface waters as a buffer in retention and removal of excess nutrients used in agricultural areas, is a solution which can be widely applied with extremely low cost. The scope of paper is to estimate the different types of riparian zones in nutrient acquisition and storage using carbon and nitrogen isotopes; with a role in reducing pollution of surface water, ground water and increase agricultural production. The study was carried out in a small catchment (45 km2) located in the Romanian Plain, in southern Romania, in an area with high potential for nutrient pollution from agricultural. Within this riparian zone five vegetation zones (agriculture (A), pasture (P), querceta forest (F1), mixed forest (F2), and wetland (W) were selected for nutrient and biomass accessions. The average annual rainfall for the catchment is 570 mm with a potential, evaporation of 717 mm. The soils of the catchment belong to two classes such as clayed and land bill. Agriculture is practiced in the majority of the land (73%) with rest occupied by forests, wetlands, other surface waters and urban development. Within agriculture wheat is the predominant crop (86%) with sunflower and maize occupy the rest. vegetation present in riparian zones of the rivers is the most important structure for nutrient uptake and to reduce nutrients into water resource. The results showed that the largest quantities of biomass are produce by mixed forest following by querceta forest, a significant

  3. Water table monitoring in a mined riparian zone

    Directory of Open Access Journals (Sweden)

    Thomaz Marques Cordeiro Andrade

    2010-04-01

    Full Text Available The objective of this study was to test an easily fabricated tool that assist in the manual installation of piezometers, as well as water table monitor in the research site, located at the Gualaxo do Norte River Watershed, state of Minas Gerais, Brazil. The tool is made of iron pipes and is a low-cost alternative for shallow groundwater observation wells. The measurements were done in a riparian zone after being gold mined, when vegetation and upper soil layers were removed. The wells were installed in three areas following a transect from the river bank. The method was viable for digging up to its maximum depth of 3 meters in a low resistance soil and can be improved to achieve a better resistance over impact and its maximum depth of perforation. Water table levels varied distinctly according to its depth in each point. It varies most in the more shallow wells in different areas, while it was more stable in the deeper ones. The water table profile reflected the probably profile f the terrain and can be a reference for its leveling in reconstitution of degraded banks where upper layers of the soil were removed. Groundwater monitoring can be also an indicator of the suitability of the substrate for soil reconstitution in terms of the maintenance of an infiltration capacity similar to the original material.

  4. Breeding bird response to partially harvested riparian management zones

    Science.gov (United States)

    Chizinski, Christopher J.; Peterson, Anna; Hanowski, JoAnn; Blinn, Charles R.; Vondracek, Bruce C.; Niemi, Gerald

    2011-01-01

    We compared avian communities among three timber harvesting treatments in 45-m wide even-age riparian management zones (RMZs) placed between upland clearcuts and along one side of first- or second-order streams in northern Minnesota, USA. The RMZs had three treatments: (1) unharvested, (2) intermediate residual basal area (RBA) (targeted goal 11.5 m2/ha, realized 16.0 m2/ha), and (3) low RBA (targeted goal 5.7 m2/ha, realized 8.7 m2/ha). Surveys were conducted one year pre-harvest and three consecutive years post-harvest. There was no change in species richness, diversity, or total abundance associated with harvest but there were shifts in the types of birds within the community. In particular, White-throated Sparrows (Zonotrichia albicollis) and Chestnut-sided Warblers (Dendroica pensylvanica) increased while Ovenbirds (Seiurus aurocapilla) and Red-eyed Vireos (Vireo olivaceus) decreased. The decline of avian species associated with mature forest in the partially harvested treatments relative to controls indicates that maintaining an unharvested RMZ adjacent to an upland harvest may aid in maintaining avian species associated mature forest in Minnesota for at least three years post-harvest. However, our observations do not reflect reproductive success, which is an area for future research.

  5. Competition favors elk over beaver in a riparian willow ecosystem

    Science.gov (United States)

    Baker, B.W.; Peinetti, H.R.; Coughenour, M.C.; Johnson, T.L.

    2012-01-01

    Beaver (Castor spp.) conservation requires an understanding of their complex interactions with competing herbivores. Simulation modeling offers a controlled environment to examine long-term dynamics in ecosystems driven by uncontrollable variables. We used a new version of the SAVANNA ecosystem model to investigate beaver (C. Canadensis) and elk (Cervus elapses) competition for willow (Salix spp.). We initialized the model with field data from Rocky Mountain National Park, Colorado, USA, to simulate a 4-ha riparian ecosystem containing beaver, elk, and willow. We found beaver persisted indefinitely when elk density was or = 30 elk km_2. The loss of tall willow preceded rapid beaver declines, thus willow condition may predict beaver population trajectory in natural environments. Beaver were able to persist with slightly higher elk densities if beaver alternated their use of foraging sites in a rest-rotation pattern rather than maintained continuous use. Thus, we found asymmetrical competition for willow strongly favored elk over beaver in a simulated montane ecosystem. Finally, we discuss application of the SAVANNA model and mechanisms of competition relative to beaver persistence as metapopulations, ecological resistance and alternative state models, and ecosystem regulation.

  6. Floral ecology and insect visitation in riparian Tamarix sp. (saltcedar)

    Science.gov (United States)

    Andersen, D.C.; Nelson, S.M.

    2013-01-01

    Climate change projections for semiarid and arid North America include reductions in stream discharge that could adversely affect riparian plant species dependent on stream-derived ground water. In order to better understand this potential impact, we used a space-for-time substitution to test the hypotheses that increasing depth-to-groundwater (DGW) is inversely related to Tamarix sp. (saltcedar) flower abundance (F) and nectar production per flower (N). We also assessed whether DGW affected the richness or abundance of insects visiting flowers. We examined Tamarix floral attributes and insect visitation patterns during 2010 and 2011 at three locations along a deep DWG gradient (3.2–4.1 m) on a floodplain terrace adjacent to Las Vegas Wash, an effluent-dominated Mojave Desert stream. Flower abundance and insect visitation patterns differed between years, but no effect from DGW on either F or N was detected. An eruption of a novel non-native herbivore, the splendid tamarisk weevil (Coniatus splendidulus), likely reduced flower production in 2011.

  7. Riparian vegetation of the Snake River in Washington State

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, R.C. [Pacific Northwest Lab., Richland, WA (United States); Mettler, L. [US Army Corps of Engineers (United States)

    1994-06-01

    In January 1992, the US Army Corps of Engineers selected reservoir drawdown and lowered pool elevation as the preferred alternative in the Columbia River Salmon Flow Measured Options Analysis/Environmental Impact Statement (EIS). During March 1992, reservoirs upstream from Lower Granite and Little Goose Dams on the Snake River were drawn down below the minimum operating pool (MOP), which is 5 vertical feet below ordinary high water level (0@) level. The reservoir upstream from Lower Granite Dam was drawn down to approximately 37 ft below 0 while that upstream of Little Goose Dam was drawn down to approximately 15 ft (4.5 m) below MOP. Following the drawdown (March 1--31, 1992), the reservoirs of all four dams in the Snake River of Washington State (Lower Granite, Little Goose, Lower Monumental, Ice Harbor) were maintained at MOP (April 1--July 31,1992). This allowed a defined portion of shoreline to be exposed for an extended period. The objectives of the study were to monitor impacts to the associated upland, riparian/wetland, and aquatic vegetation and newly exposed shorelines of four reservoirs of the Snake River during the flow measures study; and monitor the newly exposed shorelines for invasion of pioneering species during the entire period of the wildlife monitoring study.

  8. Effects of drought on birds and riparian vegetation in the Colorado River Delta, Mexico

    Science.gov (United States)

    Hinojosa-Huerta, Osvel; Nagler, Pamela L.; Carrillo-Guererro, Yamilett K.; Glenn, Edward P.

    2013-01-01

    The riparian corridor in the delta of the Colorado River in Mexico supports internationally important bird habitat. The vegetation is maintained by surface flows from the U.S. and Mexico and by a high, non-saline aquifer into which the dominant phreatophytic shrubs and trees are rooted. We studied the effects of a regional drought on riparian vegetation and avian abundance and diversity from 2002 to 2007, during which time surface flows were markedly reduced compared to the period from 1995 to 2002. Reduced surface flows led to a reduction in native tree cover but an increase in shrub cover, mostly due to an increase in Tamarix spp., an introduced halophytic shrub, and a reduction in Populus fremontii and Salix gooddingii trees. However, overall vegetation cover was unchanged at about 70%. Overall bird density and diversity were also unchanged, but riparian-obligate species tended to decrease in abundance, and generalist species increased. Although reduction in surface flows reduced habitat value and negatively impacted riparian-obligate bird species, portions of the riparian zone exhibited resilience. Surface flows are required to reduce soil salt levels and germinate new cohorts of native trees, but the main source of water supporting this ecosystem is the aquifer, derived from underflows from irrigated fields in the U.S. and Mexico. The long-term prospects for delta riparian habitats are uncertain due to expected reduced flows of river water from climate change, and land use practices that will reduce underflows to the riparian aquifer and increase salinity levels. Active restoration programs would be needed if these habitats are to be preserved for the future.

  9. Benefits of riparian forest for the aquatic ecosystem assessed at a large geographic scale

    Directory of Open Access Journals (Sweden)

    Van Looy K.

    2013-04-01

    Full Text Available Claimed benefits of riparian forest cover for the aquatic ecosystem include purification, thermal control, organic matter input and habitat provision, which may improve physicochemical and biotic quality. However, these beneficial effects might be flawed by multiple stressor conditions of intensive agriculture and urbanization in upstream catchments. We examined the relationship between riparian forest cover and physicochemical quality and biotic integrity indices in extensive large scale datasets. Measurements of hydromorphological conditions and riparian forest cover across different buffer widths for 59 × 103 river stretches covering 230 × 103 km of the French river network were coupled with data for physicochemical and biotic variables taken from the national monitoring network. General linear and quantile regression techniques were used to determine responses of physicochemical variables and biological integrity indices for macroinvertebrates and fish to riparian forest cover in selections of intermediate stress for 2nd to 4th order streams. Significant responses to forest cover were found for the nutrient variables and biological indices. According to these responses a 60% riparian forest cover in the 10 m buffer corresponds to good status boundaries for physicochemical and biotic elements. For the 30 m buffer, the observed response suggests that riparian forest coverage of at least 45% corresponds with good ecological status in the aquatic ecosystem. The observed consistent responses indicate significant potential for improving the quality of the aquatic environment by restoring riparian forest. The effects are more substantial in single-stressor environments but remain significant in multi-stressor environments.

  10. Sediment dynamics in restored riparian forest with different widths and agricultural surroundings

    Science.gov (United States)

    Stucchi Boschi, Raquel; Simões da Silva, Laura; Ribeiro Rodrigues, Ricardo; Cooper, Miguel

    2016-04-01

    The riparian forests are essential to maintaining the quality of water resources, aquifer recharge and biodiversity. Due to the ecological services provided by riparian forests, these areas are considered by the law as Permanent Preservation Areas, being mandatory maintenance and restoration. However, the obligation of restoration and the extent of the Permanent Preservation Areas as defined by the Brazilian Forest Code, based on water body width, elucidates the lack of accurate scientific data on the influence of the size of the riparian forest in maintaining their ecological functions, particularly regarding the retention of sediments. Studies that evaluate the ideal width of riparian forests to guarantee their ecological functions are scarce and not conclusive, especially when we consider newly restored forests, located in agricultural areas. In this study, we investigate the dynamics of erosion and sedimentation in restored riparian forests with different widths situated in agricultural areas. The two study areas are located in a Semideciduous Tropical Forest inserted in sugarcane landscapes of São Paulo state, Brazil. The installed plots had 60 and 100 m in length and the riparian forest has a width of 15, 30 and 50 m. The characteristics of the sediments inside the plots were evaluated by detailed morphological and micromorphological studies as well as physical characterization. The dynamics of deposition and the amount of deposited sediments have been assessed with graded metal stakes partially buried inside the plots. The intensity, frequency and distribution of rainfall, as well as the occurrence of extreme events, have been evaluated by data collected from rain gauges installed in the areas. We expect that smaller widths are not able to retain sediments originated from the adjacent sugarcane areas. We also believe that extreme events are responsible for generating most of the sediments. The results will be important to support the discussion about an

  11. Anammox bacteria community and nitrogen removal in a strip-like wetland in the riparian zone.

    Science.gov (United States)

    Pei, Yuansheng; Wang, Jun; Wang, Ziyuan; Tian, Binghui

    2011-01-01

    A strip-like wetland was constructed in the riparian zone for investigation of ammonium nitrogen (NH(3)-N) removal in the Peach River. An inner zeolite layer was set in the wetland to adsorb NH(3)-N and further to remove total nitrogen (TN). An oxygen-deficient condition with dissolved oxygen of 0.87-1.60 mg L(-1) was observed in the zeolite layer, which benefits anaerobic ammonium oxidation (anammox) bacteria survival. The community structure of anammox bacteria was analyzed in the zeolite layer. The analysis shows that the anammox bacterial sequences are grouped into three known distinct clusters: Candidatus Brocadia fulgida, Candidatus Brocadia anammoxidans and Candidatus Jettenia asiatica. The intensified test driven by artificial pumping shows that average removal rates of NH(3)-N and TN are 41.6 mg m(-3)d(-1) and 63.2 mg m(-3)d(-1), respectively. The normal test driven by natural hydrodynamics also verifies that NH(3)-N removal mainly happens in the zeolite layer. Microbial mechanism of TN removal in the wetland involves both the autotrophic and heterotrophic process. These results suggest that the strip-like RW can be a cost-effective approach for NH(3)-N removal and can potentially be extended to similar rivers as no extra energy is required to maintain the wetland operation. PMID:21644147

  12. An Investigation Into the Ecohydrology of Riparian Wetlands Along the Gila River, NM, USA

    Science.gov (United States)

    Samson, J.; Stone, M. C.

    2013-12-01

    The dynamism of the Gila River, in southwestern New Mexico, USA, has resulted in the creation of a topographically diverse floodplain that supports an array of riparian wetlands. The purpose of this study is to investigate the ecohydrologic and ecohydraulic processes of two of these wetlands, in order to predict their potential response to anthropogenic or natural changes in hydrology. One represents a natural wetland and the other a wetland that exists only as a result of an anthropogenic modification to the river system. A network of 30 wells and 2 weather stations were installed in early 2013 to provide a high resolution of data on surface water and ground water hydrologic conditions. Phreatic surface contour maps were produced to aid in the visualization of sub-surface gradients. Based on these results, an electrical resistivity investigation was conducted to identify paleoflow channels as well as depth to bedrock and other potential areas of interest. These data formed the development of three dimensional ModFlow models that were used to investigate potential future stream flow scenarios on wetland hydrology. The model outputs are being used in tandem with the results of quarterly ecological surveys on vegetation, algae, benthic, and bird communities, to make predictions of potential changes in community structure and function.

  13. Nutrient vectors and riparian nutrient processing in African semiarid savanna ecosystems

    Science.gov (United States)

    Jacobs, Shayne M.; Bechtold, J.S.; Biggs, Harry C.; Grimm, N. B.; McClain, M.E.; Naiman, R.J.; Perakis, Steven S.; Pinay, G.; Scholes, M.C.

    2007-01-01

    This review article describes vectors for nitrogen and phosphorus delivery to riparian zones in semiarid African savannas, the processing of nutrients in the riparian zone and the effect of disturbance on these processes. Semiarid savannas exhibit sharp seasonality, complex hillslope hydrology and high spatial heterogeneity, all of which ultimately impact nutrient fluxes between riparian, upland and aquatic environments. Our review shows that strong environmental drivers such as fire and herbivory enhance nitrogen, phosphorus and sediment transport to lower slope positions by shaping vegetative patterns. These vectors differ significantly from other arid and semiarid ecosystems, and from mesic ecosystems where the impact of fire and herbivory are less pronounced and less predictable. Also unique is the presence of sodic soils in certain hillslopes, which substantially alters hydrological flowpaths and may act as a trap where nitrogen is immobilized while sediment and phosphorus transport is enhanced. Nutrients and sediments are also deposited in the riparian zone during seasonal, intermittent floods while, during the dry season, subsurface movement of water from the stream into riparian soils and vegetation further enrich riparian zones with nutrients. As is found in mesic ecosystems, nutrients are immobilized in semiarid riparian corridors through microbial and plant uptake, whereas dissimilatory processes such as denitrification may be important where labile nitrogen and carbon are in adequate supply and physical conditions are suitablea??such as in seeps, wallows created by animals, ephemeral wetlands and stream edges. Interaction between temporal hydrologic connectivity and spatial heterogeneity are disrupted by disturbances such as large floods and extended droughts, which may convert certain riparian patches from sinks to sources for nitrogen and phosphorus. In the face of increasing anthropogenic pressure, the scientific challenges are to provide a basic

  14. Impact of land-surface elevation and riparian evapotranspiration seasonality on groundwater budget in MODFLOW models

    Science.gov (United States)

    Ajami, Hoori; Meixner, Thomas; Maddock, Thomas; Hogan, James F.; Guertin, D. Phillip

    2011-09-01

    Riparian groundwater evapotranspiration (ETg) constitutes a major component of the water balance especially in many arid and semi-arid environments. Although spatial and temporal variability of riparian ETg are controlled by climate, vegetation and subsurface characteristics, depth to water table (DTWT) is often considered the major controlling factor. Relationships between ETg rates and DTWT, referred to as ETg curves, are implemented in MODFLOW ETg packages (EVT, ETS1 and RIP-ET) with different functional forms. Here, the sensitivity of the groundwater budget in MODFLOW groundwater models to ETg parameters (including ETg curves, land-surface elevation and ETg seasonality) are investigated. A MODFLOW model of the hypothetical Dry Alkaline Valley in the Southwestern USA is used to show how spatial representation of riparian vegetation and digital elevation model (DEM) processing methods impact the water budget when RIPGIS-NET (a GIS-based ETg program) is used with MODFLOW's RIP-ET package, and results are compared with the EVT and ETS1 packages. Results show considerable impact on ETg and other groundwater budget components caused by spatial representation of riparian vegetation, vegetation type, fractional coverage areas and land-surface elevation. RIPGIS-NET enhances ETg estimation in MODFLOW by incorporating vegetation and land-surface parameters, providing a tool for ecohydrology studies, riparian ecosystem management and stream restoration.

  15. Regulating riparian forests for aquatic productivity in the Pacific Northwest, USA: addressing a paradox.

    Science.gov (United States)

    Newton, Michael; Ice, George

    2016-01-01

    Forested riparian buffers isolate streams from the influence of harvesting operations that can lead to water temperature increases. Only forest cover between the sun and stream limits stream warming, but that cover also reduces in-stream photosynthesis, aquatic insect production, and fish productivity. Water temperature increases that occur as streams flow through canopy openings decrease rapidly downstream, in as little as 150 m. Limiting management options in riparian forests restricts maintenance and optimization of various buffer contributions to beneficial uses, including forest products, fish, and their food supply. Some riparian disturbance, especially along cold streams, appears to benefit fish productivity. Options for enhancing environmental investments in buffers should include flexibility in application of water quality standards to address the general biological needs of fish and temporary nature of clearing induced warming. Local prescriptions for optimizing riparian buffers and practices that address long-term habitat needs deserve attention. Options and incentives are needed to entice landowners to actively manage for desirable riparian forest conditions. PMID:26611633

  16. Local values and decisions: views and constraints for riparian management in western Mexico

    Directory of Open Access Journals (Sweden)

    Flores-Díaz A.C.

    2014-05-01

    Full Text Available Human decisions on ecosystems at the local level are based significantly on the institutional context but also on how people understand and value the place where they live. Located at the land-water interface and connecting the streams with their valleys, riparian areas provide relevant services to society on regional and global scales and are important to the people directly interacting with them. Using a qualitative research approach, we documented rural people’s knowledge and values regarding the riparian system, as well as the agreements made on its management. We found positive values; a good understanding of the riparian system’s dynamics and local arrangements for its management. Degradation was also observed, indicating a discrepancy between peoples’ views and their practices. Ignorance of the national ordinances emerged as an important problem, also having consequences on the conservation of the riparian area. There are constraints between individual and collective decisions since benefits from good management are not necessarily reflected at the site, but on wider spatial-temporal scales. It is proposed (1 to consider the whole stream-riparia-parcel as a more realistic approach to assess and guide the riparian system’s role; and (2 a co-production of knowledge between local people and scientists, promoting a co-responsibility stewardship of the basin-level management.

  17. Monitoring and mapping selected riparian habitat along the lower Snake River

    Energy Technology Data Exchange (ETDEWEB)

    Downs, J. L; Tiller, B. L [Pacific Northwest Lab., Richland, WA (United States); Witter, M. [Shannon and Wilson, Inc., Seattle, WA (United States). Geotechnical and Environmental Consultants, Seattle, Washington (United States); Mazaika, R. [Corps of Engineers, Portland, OR (United States)

    1996-01-01

    Studies in this document were initiated to establish baseline information on riparian and wetland habitat conditions at the areas studied under the current reservoir operations on the lower Snake River. Two approaches were used to assess habitat at 28 study sites selected on the four pools on the lower Snake River. These areas all contribute significant riparian habitat along the river, and several of these areas are designated habitat management units. At 14 of the 28 sites, we monitored riparian habitat on three dates during the growing season to quantify vegetation abundance and composition along three transects: soil nutrients, moisture, and pH and water level and pH. A second approach involved identifying any differences in the extent and amount of riparian/wetland habitat currently found at the study areas from that previously documented. We used both ground and boat surveys to map and classify the changes in vegetative cover along the shoreline at the 14 monitoring sites and at 14 additional sites along the lower Snake selected to represent various riparian/wetland habitat conditions. Results of these mapping efforts are compared with maps of cover types previously generated using aerial photography taken in 1987.

  18. RIPGIS-NET: a GIS tool for riparian groundwater evapotranspiration in MODFLOW.

    Science.gov (United States)

    Ajami, Hoori; Maddock, Thomas; Meixner, Thomas; Hogan, James F; Guertin, D Phillip

    2012-01-01

    RIPGIS-NET, an Environmental System Research Institute (ESRI's) ArcGIS 9.2/9.3 custom application, was developed to derive parameters and visualize results of spatially explicit riparian groundwater evapotranspiration (ETg), evapotranspiration from saturated zone, in groundwater flow models for ecohydrology, riparian ecosystem management, and stream restoration. Specifically RIPGIS-NET works with riparian evapotranspiration (RIP-ET), a modeling package that works with the MODFLOW groundwater flow model. RIP-ET improves ETg simulations by using a set of eco-physiologically based ETg curves for plant functional subgroups (PFSGs), and separates ground evaporation and plant transpiration processes from the water table. The RIPGIS-NET program was developed in Visual Basic 2005, .NET framework 2.0, and runs in ArcMap 9.2 and 9.3 applications. RIPGIS-NET, a pre- and post-processor for RIP-ET, incorporates spatial variability of riparian vegetation and land surface elevation into ETg estimation in MODFLOW groundwater models. RIPGIS-NET derives RIP-ET input parameters including PFSG evapotranspiration curve parameters, fractional coverage areas of each PFSG in a MODFLOW cell, and average surface elevation per riparian vegetation polygon using a digital elevation model. RIPGIS-NET also provides visualization tools for modelers to create head maps, depth to water table (DTWT) maps, and plot DTWT for a PFSG in a polygon in the Geographic Information System based on MODFLOW simulation results. PMID:21385181

  19. Modelling the Influence of Riparian Vegetation on River Bank Erosion

    Science.gov (United States)

    Cribb, M.; Darby, S.

    2002-12-01

    Despite the recognition that riparian vegetation influences riverbank stability, many of the mechanical and hydrological mechanisms involved are yet to be fully quantified. In particular, although empirical research (e.g. Abernethy and Rutherfurd, 2001; Simon and Collison, 2002) has advanced our knowledge of the relative importance of each of these mechanisms in certain environments, results are not necessarily transferable. This is because vegetation influences bank stability via a complex suite of process mechanisms that vary in effectiveness as a function of environmental characteristics. The net effects on bank stability at an individual site are therefore difficult to predict. In the face of such complexity, numerical modelling provides a useful adjunct to empirically derived data. Modelling provides a means of analysing and isolating the influence of different vegetation assemblages, across a variety of different bank material types and physiographic settings. Herein we report preliminary results from an integrated field monitoring and numerical modelling study undertaken at six special study sites within the United Kingdom. At each site, field data have been collected to parameterise coupled simulations of pore water seepage dynamics and bank failure processes. The requisite data include bank slope surveys, in situ geotechnical testing, laboratory analyses of sedimentary and hydraulic properties of the bank materials, root tensile strength testing, and surveys of sub-surface root networks. These data are supplemented by archived hydrological and climatological data sets, enabling analyses to be performed for a range of specific flow events at each site. For each event, saturated/unsaturated flow within the riverbank is modelled using a finite element code (SEEP/W v. 5) for the seepage analysis in transient conditions (Geo-Slope International, 2001). In these simulations, model boundary conditions are adjusted to account for the hydrological effects of

  20. Denitrification and a nitrogen budget of created riparian wetlands.

    Science.gov (United States)

    Batson, Jacqulyn A; Mander, Ulo; Mitsch, William J

    2012-01-01

    Riparian wetland creation and restoration have been proposed to mediate nitrate-nitrogen (NO-N) pollution from nonpoint agricultural runoff. Denitrification by anaerobic microbial communities in wetland soils is believed to be one of the main sinks for NO-N as it flows through wetlands. Denitrification rates were quantified using an in situ acetylene inhibition technique at 12 locations in three wetland/riverine sites at the Olentangy River Wetland Research Park, Columbus, Ohio for 1 yr. Sites included two created flow-through experimental wetlands and one bottomland forest/river-edge site. Points were spatially distributed at inflows, center, and outflows of the two wetlands to include permanently flooded open water, intermittently flooded transitions, and upland. Annual denitrification rates (median [mean]) were significantly higher ( wetlands (266 [415] μg NO-N m h) than in shallower transition zones (58 [37.5] μg NO-N m h). Median wetland transition zone denitrification rates did not differ significantly ( ≥ 0.05) from riverside or upland sites. Denitrification rates peaked in spring; for the months of April through June, median denitrification rates ranged from 240 to 1010 μg NO-N m h in the permanently flooded zones. A N mass balance analysis showed that surface water flux of N was reduced by 57% as water flowed through the wetland, but only about 3.5% of the N inflow was permanently removed through denitrification. Most N was probably lost through groundwater seepage. Comparison with denitrification rates measured previously in these wetlands suggests that these rates have remained steady over the past 4 to 5 yr. PMID:23128759

  1. Dynamic processes and ecological restoration of hyporheic layer in riparian zone%河岸带潜流层动态过程与生态修复

    Institute of Scientific and Technical Information of China (English)

    夏继红; 陈永明; 王为木; 韩玉玲; 刘海洋; 胡玲

    2013-01-01

    河岸带潜流层是河岸带内地表水与地下水相互作用的生态交错带,在水文地理学、生态学、环境学上含义不尽相同.河岸带潜流层具有复杂的垂向、横向、纵向结构特征,其边缘效应显著,表现为泥沙、水流、生物、环境化学因子之间的复杂动态过程,主要包括水动力动态过程、生态学过程、溶质循环与化学过程等.水动力动态过程是驱动条件,氧气浓度是生态过程、溶质循环和化学过程的决定性因素.在各动态过程的驱动下,河岸带潜流层具有调蓄洪水、削减污染、净化缓冲环境和提供适宜栖息地等功能.针对河岸带潜流层功能退化的问题,需开展健康诊断,明确致病机理,实施适宜的生态修复.未来中国在开展河岸带潜流层研究时,应根据中国河岸带特点,采用示踪试验、数值模拟等方法,集成GIS等现代技术手段,研究多尺度下,水文条件、地形变化、土壤渗透系数、河岸带建设方式、植被分布等对河岸带潜流层水文、热传导、生化、生态等的影响机制,准确界定河岸带潜流层区域范围,制定适宜的生态修复策略.%Hyporheic layer of riparian zone is an active transition zone and ecotone between river and groundwater in riparian zone,which can be denoted respectively from hydrogeography,ecology and environment.Due to its unique structure properties in vertical,lateral and longitudinal directions,hyporheic layer of riparian zone was characterized to have some edge-effects and dynamic processes,including flow dynamics,ecological and chemical processes,which were driven by interactions among sediments,flow,communities,organic matters,solutes and environmental factors.As the three dynamic processes have affected each other and ecological and chemical processes have depended on flow dynamics driving and oxygen concentration,it has resulted that hyporheic layer in riparian zone could have stored floods and supplied

  2. Denitrification and methane/nitrous oxide emissions from recreational and agricultural riparian buffers in the southeastern United States

    Science.gov (United States)

    Denitrification was measured via the acetylene inhibition method in riparian buffers adjacent to a golf course and sites with various agronomic management and landscape positions in the southeastern Coastal Plain of the USA. Denitrification in the riparian buffers adjacent to the golf course was neg...

  3. 76 FR 20368 - Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/Fish Screen Facility Protection...

    Science.gov (United States)

    2011-04-12

    ... Fish and Wildlife Service Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/ Fish Screen...) for the proposed Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/Fish Screen Facility...) pumping plant and fish screen facility. This notice advises the public that we intend to...

  4. Influence of Herbaceous Riparian Buffers on Fish and Amphibian Communities Within Channelized Headwater Streams in Central Ohio

    Science.gov (United States)

    Herbaceous riparian buffers are a widely used conservation practice in the United States for reducing nutrient, pesticide, and sediment loadings in agricultural streams. The importance of forested riparian zones for headwater streams has been documented, but the ecological impacts of herbaceous ripa...

  5. Nitrous oxide accumulation in soils from riparian buffers of a Coastal Plain watershed - Carbon/nitrogen ratio control

    Science.gov (United States)

    Riparian buffers are used throughout the world for the protection of water bodies from nonpoint source pollution, particularly nitrogen. Yet, relatively few studies of riparian or treatment wetland denitrification consider the production of nitrous oxide. The overall objectives of this research wer...

  6. Holding onto the Green Zone: A Youth Program for the Study and Stewardship of Community Riparian Areas. Leader Guide

    Science.gov (United States)

    Reilly, Kate; Wooster, Betsy

    2008-01-01

    Riparian ecosystems are an exciting and dynamic subject for study. These areas are valuable lands and important wildlife habitats, and they contribute greatly to the environmental health of an area. Definitions for the term "riparian" vary, but in this curriculum, the land called the "Green Zone" lies between flowing water and upland ecosystems.…

  7. Riparian zone processes and soil water total organic carbon (TOC: implications for spatial variability, upscaling and carbon exports

    Directory of Open Access Journals (Sweden)

    T. Grabs

    2012-03-01

    Full Text Available Groundwater flowing from hillslopes through riparian (near stream soils often undergoes chemical transformations that can substantially influence stream water chemistry. We used landscape analysis to predict total organic carbon (TOC concentrations profiles and groundwater levels measured in the riparian zone (RZ of a 67 km2 catchment in Sweden. TOC exported from 13 riparian soil profiles was then estimated based on the riparian flow-concentration integration model (RIM. Much of the observed spatial variability of riparian TOC concentrations in this system could be predicted from groundwater levels and the topographic wetness index (TWI. Organic riparian peat soils in forested areas emerged as hotspots exporting large amounts of TOC. Exports were subject to considerable temporal variations caused by a combination of variable flow conditions and changing soil water TOC concentrations. From more mineral riparian gley soils, on the other hand, only small amounts with relatively time-invariant concentrations were exported. Organic and mineral soils in RZs constitute a heterogeneous landscape mosaic that controls much of the spatial variability of stream water TOC. We developed an empirical regression-model based on the TWI to move beyond the plot scale to predict spatially variable riparian TOC concentration profiles for RZs underlain by glacial till.

  8. Contribution of Wetland Resources to Household Incomes of Riparian Communities of Katonga Wetland in Mpigi District, Uganda

    Directory of Open Access Journals (Sweden)

    E. Kateyo

    2014-05-01

    Full Text Available Katonga wetland which lies to the western part of Lake Victoria covers an area of 237.4 km2. Although the wetland is known to contain flora and fauna that support livelihoods, there has been lack of information on the economic value of these resources and their contribution to livelihoods particularly of the rural riparian communities. The objective of the study was to generate information on the vital wetland resources, the economic value and contribution of these resources to riparian community livelihoods. The study was carried out in Nkozi and Kituntu sub-counties in Mpigi District-Uganda; it covered six parishes through which the wetland runs and involved 120 respondents. The study established that resources in the wetland are collected for subsistence and direct commercial extraction. The most important resource derived from the wetland for subsistence use was water for rural domestic use with each household using an average of 188l per day (23l per person and was estimated at an annual economic value of Uganda shillings (Ushs 490,191 (U$ 233.4 per person per year. Fisheries were the most important commercial activities undertaken in these parts of the wetland involving 36% of respondents collecting an average of 119kg per week with an estimated annual value of Ushs. 3,991,367 (U$ 1,900.6 per person. These activities particularly collection of water and fuel wood are undertaken throughout the year, while harvesting of craft materials is mainly done during the dry season (January-March and June-August. Fishing is done mainly in the wet season (March-May and September-November. he wetland is a source of income for at least 74% of the respondents. The majority of respondents, 57.5%, were among low income groups earning up to Ushs 600,000 per respondent annually. Fishing provides the highest gross incomes per respondent Ushs 200,000 per month hence the high value of the wetland to its riparian communities. It was noted that 30% of respondents

  9. Radionuclide transport along a boreal hill slope - elevated soil water concentrations in riparian forest soils

    International Nuclear Information System (INIS)

    The transport of radionuclides from forest ecosystems and out into surface waters is a crucial process for understanding the long-term fate of radionuclides in the boreal landscape. Boreal forests are typically dominated by podzol soils, but the streams draining the forests are often lined by highly organic, often peat-like soils, which the radionuclides must pass through in order to reach the stream. This so-called riparian zone therefore represents a fundamentally different biogeochemical environment than ordinary forest soils, e.g. by exhibiting significantly lower pH and higher concentrations of organic colloids, which significantly can affect the mobility of many radionuclides. Since the riparian zone is the last terrestrial environment that the groundwater is in contact with before it enters the stream, previous research has demonstrated its profound impact on the stream water chemistry. Hence, the riparian soils should also be important for the transport and accumulation of radionuclides. Therefore, soil water was sampled using suction lysimeters installed at different depths along a 22 m long forested hill slope transect in northern Sweden, following the flow pathway of the groundwater from the uphill podzol to the riparian zone near the stream channel. The analyses included a wide range of hydrochemical parameters and many radiologically important elements, e.g. U, Th, Ni, C, Sr, Cs, REEs and Cl. The sampling was repeated ten times throughout a year in order to also capture the temporal variability of the soil water chemistry. The water chemistry of the investigated transect displayed a remarkable change as the groundwater approached the stream channel. Strongly increased concentrations of many elements were observed in the riparian soils. For instance, the concentrations of Th were more than 100 times higher than in the riparian zone than in the uphill forest, suggesting that the riparian zone may be a hotspot for radionuclide accumulation. The reason

  10. Surface runoff generation in a small watershed covered by sugarcane and riparian forest

    Directory of Open Access Journals (Sweden)

    Rafael Pires Fernandes

    2013-12-01

    Full Text Available Since an understanding of how runoff is generated is of great importance to soil conservation, to water availability and to the management of a watershed, the objective of this study was to understand the generation of surface runoff in a watershed covered by sugarcane and riparian forest. Nine surface runoff plots were set up, evenly distributed on the lower, middle and upper slopes. The lower portion was covered by riparian forest. We showed that the average surface runoff coefficient along the slope in the present study was higher than in other studies under different land uses. Furthermore, the surface runoff was higher under sugarcane compared to the riparian forest, especially after sugarcane harvesting. Besides land cover, other factors such as the characteristics of rainfall events, relief and physical soil characteristics such as soil bulk density and saturated hydraulic conductivity influenced the surface runoff generation.

  11. Management of riparian habitat for mammals, birds, reptiles, and amphibians. Appendix C

    Science.gov (United States)

    Knutson, M.G.; Ribic, C.

    1999-01-01

    Melinda Knutson (USGS Upper Midwest Environmental Sciences Center) and Christine Ribic (USGS Wisconsin Cooperative Wildlife Research Unit) contributed to a recent report published by the USDA Natural Resources Conservation Service. The report summarizes a workshop held 8 December 1999 in Chicago, IL. Highlights of the report include resources and land management recommendations for riparian zones in the Midwest. The full report will soon be available at the USDA NRCS Wildlife Habitat Management Institute website: http://www.ms.nrcs.usda.gov/whmi/habitat.htm Knutson, M., and C. Ribic. 2000. Management of riparian habitat for mammals, birds, reptiles, and amphibians. Pages 22-24, Appendix C in W. Hohman, ed. NRCS Management and Restoration of Midwestern Riparian Systems Workshop Report. USDA Natural Resources Conservation Service, Chicago, IL.

  12. Evapotranspiration Calculation on the Basis of the Riparian Zone Water Balance

    Directory of Open Access Journals (Sweden)

    SZILÁGYI, József

    2008-01-01

    Full Text Available Riparian forests have a strong influence on groundwater levels and groundwater sustainedstream baseflow. An empirical and a hydraulic version of a new method were developed to calculateevapotranspiration values from riparian zone groundwater levels. The new technique was tested on thehydrometeorological data set of the Hidegvíz Valley (located in Sopron Hills at the eastern foothills ofthe Alps experimental catchment. Evapotranspiration values of this new method were compared tothe Penman-Monteith evapotranspiration values on a half hourly scale and to the White methodevapotranspiration values on a daily scale. Sensitivity analysis showed that the more reliable hydraulicversion of our ET estimation technique is most sensitive (i.e., linearly to the values of the saturatedhydraulic conductivity and specific yield taken from the riparian zone.

  13. Radionuclide transport along a boreal hill slope - elevated soil water concentrations in riparian forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Lidman, Fredrik; Boily, Aasa; Laudon, Hjalmar [Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901 83 Umeaa (Sweden); Koehler, Stephan J. [Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, P.O. 7050, 750 07 Uppsala (Sweden)

    2014-07-01

    The transport of radionuclides from forest ecosystems and out into surface waters is a crucial process for understanding the long-term fate of radionuclides in the boreal landscape. Boreal forests are typically dominated by podzol soils, but the streams draining the forests are often lined by highly organic, often peat-like soils, which the radionuclides must pass through in order to reach the stream. This so-called riparian zone therefore represents a fundamentally different biogeochemical environment than ordinary forest soils, e.g. by exhibiting significantly lower pH and higher concentrations of organic colloids, which significantly can affect the mobility of many radionuclides. Since the riparian zone is the last terrestrial environment that the groundwater is in contact with before it enters the stream, previous research has demonstrated its profound impact on the stream water chemistry. Hence, the riparian soils should also be important for the transport and accumulation of radionuclides. Therefore, soil water was sampled using suction lysimeters installed at different depths along a 22 m long forested hill slope transect in northern Sweden, following the flow pathway of the groundwater from the uphill podzol to the riparian zone near the stream channel. The analyses included a wide range of hydrochemical parameters and many radiologically important elements, e.g. U, Th, Ni, C, Sr, Cs, REEs and Cl. The sampling was repeated ten times throughout a year in order to also capture the temporal variability of the soil water chemistry. The water chemistry of the investigated transect displayed a remarkable change as the groundwater approached the stream channel. Strongly increased concentrations of many elements were observed in the riparian soils. For instance, the concentrations of Th were more than 100 times higher than in the riparian zone than in the uphill forest, suggesting that the riparian zone may be a hotspot for radionuclide accumulation. The reason

  14. The influence of riparian-hyporheic zone on the hydrological responses in an intermittent stream

    Directory of Open Access Journals (Sweden)

    A. Butturini

    2002-01-01

    Full Text Available Stream and riparian groundwater hydrology has been studied in a small intermittent stream draining a forested catchment for a system representative of a Mediterranean climate. The relationship between precipitation and stream runoff and the interactions between stream water and the surrounding riparian groundwater have been analysed under a wide spectrum of meteorological conditions. The hypothesis that the hydrological condition of the near-stream groundwater compartment can regulate the runoff generation during precipitation events was tested. Stream runoff is characterised by a summer dry period, and precipitation input explained only 25% of runoff variability over the study period (r2 =0.25, d.f.=51, p2=0.80, d.f.=34, p Keywords: riparian zone, groundwater hydrology, runoff, intermittent stream, Mediterranean climate

  15. Floristic composition of the riparian forest in the lower Gramame river, Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Hermes de Oliveira Machado Filho

    2015-09-01

    Full Text Available Riparian forest has a key ecological and economic significance to productive chains associated with it. This study aimed to conduct a floristic survey of riparian forest stretches in the Gramame river, state of Paraíba, Brazilian Northeast region, and analyze the floristic similarity with Brazilian riparian vegetation fragments. We found 136 species belonging to 106 genera and 43 families. The most representative families were: Fabaceae (19 spp., Cyperaceae (16 spp., and Rubiaceae (11 spp.. The predominant habit was herbaceous and the best represented biological spectrum was camephyte. Regarding the geographic distribution, there was a predominance of widely distributed species associated with the Neotropical province. The distribution patterns have shown a low similarity between areas, and largely distributed species stand out. Similarity analysis pointed out that the area was floristically related to other two coastal areas in the Brazilian Northeast and Southeast regions. Only species typically related to estuarine environments might explain the floristic connections detected.

  16. Beyond cool: adapting upland streams for climate change using riparian woodlands.

    Science.gov (United States)

    Thomas, Stephen M; Griffiths, Siân W; Ormerod, Steve J

    2016-01-01

    Managed adaptation could reduce the risks of climate change to the world's ecosystems, but there have been surprisingly few practical evaluations of the options available. For example, riparian woodland is advocated widely as shade to reduce warming in temperate streams, but few studies have considered collateral effects on species composition or ecosystem functions. Here, we use cross-sectional analyses at two scales (region and within streams) to investigate whether four types of riparian management, including those proposed to reduce potential climate change impacts, might also affect the composition, functional character, dynamics and energetic resourcing of macroinvertebrates in upland Welsh streams (UK). Riparian land use across the region had only small effects on invertebrate taxonomic composition, while stable isotope data showed how energetic resources assimilated by macroinvertebrates in all functional guilds were split roughly 50:50 between terrestrial and aquatic origins irrespective of riparian management. Nevertheless, streams draining the most extensive deciduous woodland had the greatest stocks of coarse particulate matter (CPOM) and greater numbers of 'shredding' detritivores. Stream-scale investigations showed that macroinvertebrate biomass in deciduous woodland streams was around twice that in moorland streams, and lowest of all in streams draining non-native conifers. The unexpected absence of contrasting terrestrial signals in the isotopic data implies that factors other than local land use affect the relative incorporation of allochthonous subsidies into riverine food webs. Nevertheless, our results reveal how planting deciduous riparian trees along temperate headwaters as an adaptation to climate change can modify macroinvertebrate function, increase biomass and potentially enhance resilience by increasing basal resources where cover is extensive (>60 m riparian width). We advocate greater urgency in efforts to understand the ecosystem

  17. Estimating Riparian and Agricultural Actual Evapotranspiration by Reference Evapotranspiration and MODIS Enhanced Vegetation Index

    Directory of Open Access Journals (Sweden)

    Russell L. Scott

    2013-08-01

    Full Text Available Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ETa based on the Enhanced Vegetation Index (EVI from the Moderate Resolution Imaging Spectrometer (MODIS sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ETo. The algorithm was calibrated with five years of ETa data from three eddy covariance flux towers set in riparian plant associations on the upper San Pedro River, Arizona, supplemented with ETa data for alfalfa and cotton from the literature. The algorithm was based on an equation of the form ETa = ETo [a(1 − e−bEVI − c], where the term (1 − e−bEVI is derived from the Beer-Lambert Law to express light absorption by a canopy, with EVI replacing leaf area index as an estimate of the density of light-absorbing units. The resulting algorithm capably predicted ETa across riparian plants and crops (r2 = 0.73. It was then tested against water balance data for five irrigation districts and flux tower data for two riparian zones for which season-long or multi-year ETa data were available. Predictions were within 10% of measured results in each case, with a non-significant (P = 0.89 difference between mean measured and modeled ETa of 5.4% over all validation sites. Validation and calibration data sets were combined to present a final predictive equation for application across crops and riparian plant associations for monitoring individual irrigation districts or for conducting global water use assessments of mixed agricultural and riparian biomes.

  18. Estimating riparian and agricultural evapotranspiration by reference crop evapotranspiration and MODIS Enhanced Vegetation Index

    Science.gov (United States)

    Nagler, Pamela L.; Glenn, Edward P.; Nguyen, Uyen; Scott, Russell; Doody, Tania

    2013-01-01

    Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ETa) based on the Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ETo). The algorithm was calibrated with five years of ETa data from three eddy covariance flux towers set in riparian plant associations on the upper San Pedro River, Arizona, supplemented with ETa data for alfalfa and cotton from the literature. The algorithm was based on an equation of the form ETa = ETo [a(1 − e−bEVI) − c], where the term (1 − e−bEVI) is derived from the Beer-Lambert Law to express light absorption by a canopy, with EVI replacing leaf area index as an estimate of the density of light-absorbing units. The resulting algorithm capably predicted ETa across riparian plants and crops (r2 = 0.73). It was then tested against water balance data for five irrigation districts and flux tower data for two riparian zones for which season-long or multi-year ETa data were available. Predictions were within 10% of measured results in each case, with a non-significant (P = 0.89) difference between mean measured and modeled ETa of 5.4% over all validation sites. Validation and calibration data sets were combined to present a final predictive equation for application across crops and riparian plant associations for monitoring individual irrigation districts or for conducting global water use assessments of mixed agricultural and riparian biomes.

  19. Climate correlates of 20 years of trophic changes in a high-elevation riparian system

    Science.gov (United States)

    Martin, T.E.

    2007-01-01

    The consequences of climate change for ecosystem structure and function remain largely unknown. Here, I examine the ability of climate variation to explain long-term changes in bird and plant populations, as well as trophic interactions in a high-elevation riparian system in central Arizona, USA, based on 20 years of study. Abundances of dominant deciduous trees have declined dramatically over the 20 years, correlated with a decline in overwinter snowfall. Snowfall can affect overwinter presence of elk, whose browsing can significantly impact deciduous tree abundance. Thus, climate may affect the plant community indirectly through effects on herbivores, but may also act directly by influencing water availability for plants. Seven species of birds were found to initiate earlier breeding associated with an increase in spring temperature across years. The advance in breeding time did not affect starvation of young or clutch size. Earlier breeding also did not increase the length of the breeding season for single-brooded species, but did for multi-brooded species. Yet, none of these phenology-related changes was associated with bird population trends. Climate had much larger consequences for these seven bird species by affecting trophic levels below (plants) and above (predators) the birds. In particular, the climate-related declines in deciduous vegetation led to decreased abundance of preferred bird habitat and increased nest predation rates. In addition, summer precipitation declined over time, and drier summers also were further associated with greater nest predation in all species. The net result was local extinction and severe population declines in some previously common bird species, whereas one species increased strongly in abundance, and two species did not show clear population changes. These data indicate that climate can alter ecosystem structure and function through complex pathways that include direct and indirect effects on abundances and interactions

  20. Monitoring of riparian vegetation response to flood disturbances using terrestrial photography

    OpenAIRE

    K. Džubáková; P. Molnar; K. Schindler; M. Trizna

    2015-01-01

    Flood disturbance is one of the major factors impacting riparian vegetation on river floodplains. In this study we use a high-resolution ground-based camera system with near-infrared sensitivity to quantify the immediate response of riparian vegetation in an Alpine, gravel bed, braided river to flood disturbance with the use of vegetation indices. Five large floods with return periods between 1.4 and 20.1 years in the period 2008–2011 in the Maggia River were analysed to eva...

  1. Estrutura e síndromes de dispersão de espécies arbóreas em um trecho de mata ciliar, Sirinhaém, Pernambuco, Brasil Structure and dispersal syndromes of tree species in a stretch of riparian vegetation, Sirinhaém, Pernambuco State, Brazil

    Directory of Open Access Journals (Sweden)

    Roseane Karla Soares da Silva

    2012-03-01

    Full Text Available

    Este trabalho teve por objetivo conhecer a fitossociologia do componente arboreo em uma mata ciliar de um corrego que desagua no Rio Sirinhaem, localizado no Engenho Buranhem, Sirinhaem, PE e identificar as sindromes de dispersao das especies. O corrego esta situado em um fragmento de Floresta Ombrofila Densa de Terras Baixas, com 272 ha. Utilizou-se como area amostral um hectare (40 unidades amostrais, 10 m x 25 m onde foram registrados 1.307 individuos arboreos com circunferencia a altura do peito (CAP ≥ 15 cm. Foram identificadas 118 especies, pertencentes a 40 familias botanicas. Protium heptaphyllum e Pouteria sp.1 foram as especies mais abundantes. Em termos de valor de importancia (VI, as especies Protium heptaphyllum, Pouteria sp.1 e Virola gardneri estao entre as mais importantes ecologicamente. As sindromes de dispersao predominantes foram: zoocoria (72,8%, autocoria (13,6% e anemocoria (4,8%. Nao foi possivel determinar a sindrome de dispersao de 8,8% das especies estudadas.

     

    doi: 10.4336/2012.pfb.32.69.01

    This study aimed to know the phytosociology of the tree component of riparian vegetation in a stream that flows into the Sirinhaem River in Engenho Buranhem, Sirinhaem, Pernambuco State, and identify the species dispersal syndromes. The stream is located in a fragment of dense rain forest of the lowlands, with 272 ha. It was sempled used one hectare (40 sampling units of 10 m x 25 m each. It was registered 1,307 trees with circumference at breast height (CAP . 15 cm. We identified 118 species belonging to 40 botanical families. Protium heptaphyllum and Pouteria sp.1 were the most abundant species. In terms of importance value (IV, Protium heptaphyllum, Pouteria sp.1 and Virola gardneri are among the most important ecologically species. The predominant dispersal syndromes were zoocory (72.8%, autocory (13.6% and anemochory (4.8%. It was not possible to determine the type of dispersal of 8.8% of the

  2. How spatial variation in areal extent and configuration of labile vegetation states affect the riparian bird community in Arctic tundra.

    Directory of Open Access Journals (Sweden)

    John-André Henden

    Full Text Available The Arctic tundra is currently experiencing an unprecedented combination of climate change, change in grazing pressure by large herbivores and growing human activity. Thickets of tall shrubs represent a conspicuous vegetation state in northern and temperate ecosystems, where it serves important ecological functions, including habitat for wildlife. Thickets are however labile, as tall shrubs respond rapidly to both abiotic and biotic environmental drivers. Our aim was to assess how large-scale spatial variation in willow thicket areal extent, configuration and habitat structure affected bird abundance, occupancy rates and species richness so as to provide an empirical basis for predicting the outcome of environmental change for riparian tundra bird communities. Based on a 4-year count data series, obtained through a large-scale study design in low arctic tundra in northern Norway, statistical hierarchical community models were deployed to assess relations between habitat configuration and bird species occupancy and community richness. We found that species abundance, occupancy and richness were greatly affected by willow areal extent and configuration, habitat features likely to be affected by intense ungulate browsing as well as climate warming. In sum, total species richness was maximized in large and tall willow patches of small to intermediate degree of fragmentation. These community effects were mainly driven by responses in the occupancy rates of species depending on tall willows for foraging and breeding, while species favouring other vegetation states were not affected. In light of the predicted climate driven willow shrub encroachment in riparian tundra habitats, our study predicts that many bird species would increase in abundance, and that the bird community as a whole could become enriched. Conversely, in tundra regions where overabundance of large herbivores leads to decreased areal extent, reduced height and increased fragmentation

  3. Water Tables, Flooding, and Water Use by Riparian Phreatophyte Communities

    Science.gov (United States)

    Thibault, J. R.; Cleverly, J. R.; Dahm, C.

    2010-12-01

    Phreatophytic riparian vegetation relies heavily on ground water transported from upstream sources. In the American southwest, the phenology of native phreatophytes, e.g., Rio Grande cottonwood, (Populus deltoides) is also dependent on seasonal flooding, which has been greatly diminished by hydrologic alterations and competing allocations. In this semi-arid, water-scarce region, a long history of agriculture and a rapidly expanding population impose limits on water available for ecological purposes, such as managed, restorative flooding. At native and non-native (e.g., saltcedar, (Tamarix spp.)) sites along the Rio Grande floodplain of central New Mexico, eddy covariance flux towers and monitoring wells are deployed to quantify evapotranspiration (ET) and investigate relationships between ET, water table (WT) depth, and flooding. Season-long measurements have been completed over several years in flooding and non-flooding sites under climatic conditions fluctuating from wet to extreme drought. Total growing season ET declines with deeper WTs across sites, with robust correlations where strong hydrologic connections exist between the river and ground water. As such, wet years with elevated WTs result in greater annual ET. However, ET responds less clearly to floods within the growing season. Longer duration floods lasting several weeks are more typical earlier in the growing season, associated with sufficient snowmelt runoff. Extensive spring flooding in two recent years coincided with significantly higher ET at a young, mixed stand, but had no effect on ET at a mature saltcedar forest. Summer monsoons and drier springs typically bring more transitory flood pulses with rapid WT ascent and decline measured in days. Elevated ET occurred during only one of several shorter flood pulses, at a saltcedar site during an otherwise dry spring. ET was not affected by monsoon flood pulses. Recruitment of native vegetation requires spring floods with favorable timing, magnitude

  4. Wheeler County Riparian Buffers; 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Potter, Judy; Homer, Will (Wheeler County Soil and Water Conservation District, John Day, OR)

    2004-02-01

    Problems Encountered During Contract Year--Wheeler County residents are mostly non participants when it comes to Farm Services programs. Results of the counties non participation is the rental rates are the lowest in the state. There is a government fear factor as well as an obvious distance limitation. The FSA office is nearly 150 mile roundtrip from two of the counties urban areas. I find myself not only selling the CREP-Riparian Buffer but also selling Farm Services in general. Training has been very limited. NRCS is obviously not designed around training and certification. They are an on-the-job training organization. It has caused a hesitation in my outreach program and a great deal of frustration. I feel my confidence will strengthen with the follow through of the current projects. The most evident problem has come to light as of late. The program is too expensive to implement. The planting is too intensive for a 12''-18'' rainfall area. I provide the potential landowner a spread sheet with the bonuses, the costs, and the final outcome. No matter the situation, CREP or CCRP, the landowner always balks at the cost. The program assumes the landowner has the capital to make the initial investment. For example, project No.2 is going to be a minimum width buffer. It is approximately 3,000 ft long and 5.5 acres. The buffer for tree planting and fencing alone will result in a cost of nearly $13,000. With the water developments it nears $23,000. That is nearly 10% of a 250 mother-cow operating budget. Project No.1, the tree planting estimate is $45,000. This alone is nearly 25% of the same type of budget. I would greatly appreciate any help in finding a third party willing to put money to work covering the initial costs of the program, expecting reimbursement from Farm Services Agency. I believe this could create a powerful tool in buffering streams in Wheeler County. Outlook for Contract Year 2--I have been in this position now for 6 months. I am

  5. Landscape gradients and patchiness in riparian vegetation on a Middle Pennsylvanian braided-river plain prone to flood disturbance (Nýrany Member, Central and Western Bohemian Basin, Czech Republic)

    DEFF Research Database (Denmark)

    Bashforth, Arden Roy; Drábková, Jana; Opluštil, Stanislav;

    2011-01-01

    , the composition and structure of megafloral assemblages remains unchanged through thin stratigraphic intervals, indicating short-term persistence and resilience of communities. Non-metric multi-dimensional scaling exposes habitat partitioning between different plant groups, which were organized along...... avulsion and flooding. Taphonomic observations and multivariate analysis of 41 quadrats containing mostly (par)autochthonous megafloral assemblages reveal that riparian vegetation comprised a collage of monospecific to low-diversity communities, with patchiness prevalent at local and regional scales. The...

  6. Estimating riparian understory vegetation cover with beta regression and copula models

    Science.gov (United States)

    Eskelson, Bianca N.I.; Madsen, Lisa; Hagar, Joan C.; Temesgen, Hailemariam

    2011-01-01

    Understory vegetation communities are critical components of forest ecosystems. As a result, the importance of modeling understory vegetation characteristics in forested landscapes has become more apparent. Abundance measures such as shrub cover are bounded between 0 and 1, exhibit heteroscedastic error variance, and are often subject to spatial dependence. These distributional features tend to be ignored when shrub cover data are analyzed. The beta distribution has been used successfully to describe the frequency distribution of vegetation cover. Beta regression models ignoring spatial dependence (BR) and accounting for spatial dependence (BRdep) were used to estimate percent shrub cover as a function of topographic conditions and overstory vegetation structure in riparian zones in western Oregon. The BR models showed poor explanatory power (pseudo-R2 ≤ 0.34) but outperformed ordinary least-squares (OLS) and generalized least-squares (GLS) regression models with logit-transformed response in terms of mean square prediction error and absolute bias. We introduce a copula (COP) model that is based on the beta distribution and accounts for spatial dependence. A simulation study was designed to illustrate the effects of incorrectly assuming normality, equal variance, and spatial independence. It showed that BR, BRdep, and COP models provide unbiased parameter estimates, whereas OLS and GLS models result in slightly biased estimates for two of the three parameters. On the basis of the simulation study, 93–97% of the GLS, BRdep, and COP confidence intervals covered the true parameters, whereas OLS and BR only resulted in 84–88% coverage, which demonstrated the superiority of GLS, BRdep, and COP over OLS and BR models in providing standard errors for the parameter estimates in the presence of spatial dependence.

  7. Spectral discrimination of giant reed (Arundo donax L.): A seasonal study in riparian areas

    Science.gov (United States)

    Fernandes, Maria Rosário; Aguiar, Francisca C.; Silva, João M. N.; Ferreira, Maria Teresa; Pereira, José M. C.

    2013-06-01

    The giant reed (Arundo donax L.) is amongst the one hundred worst invasive alien species of the world, and it is responsible for biodiversity loss and failure of ecosystem functions in riparian habitats. In this work, field spectroradiometry was used to assess the spectral separability of the giant reed from the adjacent vegetation and from the common reed, a native similar species. The study was conducted at different phenological periods and also for the giant reed stands regenerated after mechanical cutting (giant reed_RAC). A hierarchical procedure using Kruskal-Wallis test followed by Classification and Regression Trees (CART) was used to select the minimum number of optimal bands that discriminate the giant reed from the adjacent vegetation. A new approach was used to identify sets of wavelengths - wavezones - that maximize the spectral separability beyond the minimum number of optimal bands. Jeffries Matusita and Bhattacharya distance were used to evaluate the spectral separability using the minimum optimal bands and in three simulated satellite images, namely Landsat, IKONOS and SPOT. Giant reed was spectrally separable from the adjacent vegetation, both at the vegetative and the senescent period, exception made to the common reed at the vegetative period. The red edge region was repeatedly selected, although the visible region was also important to separate the giant reed from the herbaceous vegetation and the mid infrared region to the discrimination from the woody vegetation. The highest separability was obtained for the giant reed_RAC stands, due to its highly homogeneous, dense and dark-green stands. Results are discussed by relating the phenological, morphological and structural features of the giant reed stands and the adjacent vegetation with their optical traits. Weaknesses and strengths of the giant reed spectral discrimination are highlighted and implications of imagery selection for mapping purposes are argued based on present results.

  8. Connecting Seasonal Riparian Buffer Metrics and Nitrogen Concentrations in a Pulse-Driven Agricultural System

    Science.gov (United States)

    Riparian buffers have been well studied as best management practices for nutrient reduction at field scales yet their effectiveness for bettering water quality at watershed scales has been difficult to determine. Seasonal dynamics of the stream network are often overlooked when ...

  9. Mitigation of Shallow Groundwater Nitrate in a Poorly Drained Riparian Area and Adjacent Cropland

    Science.gov (United States)

    Riparian ecosystems, through their unique positions in the agricultural landscape and ability to influence nutrient cycles, have the potential to mitigate nutrient loading to surface and ground waters. The purpose of this study was to determine the fate of NO3 in shallow ground water moving along a...

  10. Restoration of a Severely Impacted Riparian Wetland System-The Pen Branch Project

    International Nuclear Information System (INIS)

    The Pen Banch riparian wetland system was impacted by hot water releases from the reactor operations at the SRS. Several hundred acres of swamp and bottomland forest were destroyed and degraded as a result of thermal effects and sedimentation. The SRS developed a plan to restore the system based upon planting both early and last successional tree species. The goal was to develop a

  11. AN INTERDISCIPLINARY APPROACH TO RIPARIAN MEADOW CHARACTERIZATION AND PRIORITIZATION, CENTRAL GREAT BASIN

    Science.gov (United States)

    The Great Basin Ecosystem Management Research group has described the hydrological, geophysical, and geomorphic conditions that lead to the formation and maintenance of riparian meadows of central Nevada. Previous work on these systems has focused on understanding a few study mea...

  12. Sustainable cropping systems using cover crops, native species field borders and riparian buffers for environmental quality

    Science.gov (United States)

    This presentation will focus on the application of sustainable management practices for no-till cultivation using cover crops, native species field borders, and fast growing woody species integrated in vegetative strips and riparian buffers. An ongoing field project at the Bradford Research and Exte...

  13. How Riparian Vegetation Influences Stream Morphology and Process: Implications for Restoration

    Science.gov (United States)

    Pizzuto, J. E.

    2005-05-01

    Vegetation is often used to enhance bank stabilization efforts and as part of more generalized restoration designs, but the influence of vegetation on geomorphic processes is poorly understood. Recent research suggests that changes in riparian vegetation can influence channel morphology, rates of erosion and deposition, and by extension, the entire sediment budget of a reach. In recent studies in the Mid-Atlantic region, reaches with forested riparian vegetation were compared to immediately adjacent non-forested (grassy) riparian vegetation to explain why channels with forested vegetation are wider than their non-forested counterparts. At study sites, erosion occurs at cutbanks in curving reaches, while deposition is localized on active floodplains at the insides of bends. In narrow, non-forested reaches, rates of bank erosion and channel migration are high, while in wide, forested reaches, rates of bank erosion and channel migration are low. These results may be explained using the ratio of two dimensionless parameters, alpha and E. Alpha represents the influence of vegetation on rates of active floodplain deposition (it is very high in non-forested reaches, and very low in forested reaches), while E is proportional to rates of cutbank migration (it is high in non-forested areas and low in forested areas). The width is proportional to E/alpha. These results could lead to improved assessment of the geomorphic effects of restoration designs that involve changes in riparian vegetation.

  14. Riparian buffer strips as a multifunctional management tool in agricultural landscapes: Introduction to the special collection

    NARCIS (Netherlands)

    Stutter, M.I.; Chardon, W.J.; Kronvang, B.

    2012-01-01

    Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented “edge of field” mitigation measure assumed

  15. Protocol for Large-scale Monitoring of Riparian-Associated Mammals

    Directory of Open Access Journals (Sweden)

    Damon B Lesmeister

    2011-10-01

    Full Text Available The design of large-scale wildlife monitoring programs must include long term and geographically broad methods of collecting reliable information on the status and trends in populations, with the overarching goal of providing inference about ecosystem health. We developed a monitoring protocol for populations of beaver (Castor canadensis, American mink (Neovison vison, muskrat (Ondatra zibethicus, and North American river otter (Lontra canadensis in Illinois, USA. The goals of the monitoring program are to (1 determine the distribution, status and trends of riparian-associated mammal species in Illinois; (2 provide early warning of population declines; (3 contribute to baseline information and improve understanding of ecosystem dynamics; (4 produce data to meet certain legal mandates related to natural resource protection; and (5 measure progress towards wildlife management goals. We developed the riparian-associated mammal protocol in an occupancy modeling framework and provide estimates regarding 2 levels of precision. The estimated number of sites required to meet benchmark precision values was consistently 4 times greater for management objectives requiring more certainty. As estimated occupancy and detection probability increased, estimates of the number of sites necessary to achieve the desired precision decreased. Based on our analysis, goals, and logistical constraints of the Illinois Department of Natural Resources, monitoring 193 sites selected from Illinois Environmental Protection Agency river and stream monitoring sites for riparian-associated mammals is the most appropriate goal. The scientifically sound information obtained through this monitoring program will have multiple applications for wildlife management and understanding of riparian ecosystem dynamics.

  16. Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams.

    Science.gov (United States)

    Magner, Joseph A; Vondracek, Bruce; Brooks, Kenneth N

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response. PMID:18481141

  17. Grazed Riparian Management and Stream Channel Response in Southeastern Minnesota (USA) Streams

    Science.gov (United States)

    Magner, Joseph A.; Vondracek, Bruce; Brooks, Kenneth N.

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response.

  18. Riparian shrub metal concentrations and growth in amended fluvial mine tailings

    Science.gov (United States)

    Fluvial mine tailing deposition has caused extensive riparian damage throughout the western United States. Willows are often used for fluvial mine tailing revegetation, but some species accumulate excessive metal concentrations which could be detrimental to browsers. In a greenhouse experiment, gr...

  19. Denitrification gene density across a wastewater-impacted riparian buffer zone

    Science.gov (United States)

    Riparian buffers are a best management practice used extensively to protect water bodies from agriculturally-generated nitrate pollution. In particular, the biological process of denitrification has been shown to be a sink for this nitrate. Denitrification results in the reduction of nitrate under a...

  20. Effects of flow regulation and fragmentation by dams on riparian flora in boreal rivers

    International Nuclear Information System (INIS)

    The object of this thesis is to evaluate the effects of river regulation on riparian flora in boreal rivers, and to increase the understanding of the processes causing patterns in species diversity. Comparisons of free-flowing and regulated rivers showed that regulated rivers have fewer plant species and less plant cover per 200-m-stretch of river margin. Regulated river-margins were less species-rich compared to free-flowing rivers irrespective of the type of regulated water level regime, except for unimpounded reaches downstream of dams. Species with good dispersal capacity (wind-dispersed or long-floating species) were least affected by regulation, showing that the ability to recolonize after local extinction is an important character. The temporal development of river-margin vegetation in regulated rivers was studied by investigating differently-old reservoirs and impoundments. Plant-species richness along storage reservoirs increased during the first 30-40 years following damming, but declined thereafter. Both species richness and plant cover remained impoverished compared to free-flowing rivers about 70 years after regulation. Along run-of-river impoundments, plant species richness and cover peaked after 10-20 years. In the long run, riparian species richness was lower, but riparian species density did not differ, compared to free-flowing rivers. Dams fragment the riparian flora. Adjacent run-of-river impoundments developed different riparian floras, probably because dams are barriers to the dispersal of species with poor floating ability. This shows that dams disrupt the ecological continuity not only for the river channel, but also for the adjoining riparian corridor. The number of species and genera were similar between river margins along boreal free-flowing rivers in Europe and North America. The riparian floras shared few species but many genera and families. The regional species pools were similar-sized and composed of species with similar traits, and

  1. Diversity, composition and phenology of araneid orb-weavers (Araneae, Araneidae associated with riparian forests in southern Brazil

    Directory of Open Access Journals (Sweden)

    Everton N. L. Rodrigues

    2015-03-01

    Full Text Available The Araneidae is a speciose family including web-spinning spiders that are very abundant in various terrestrial ecosystems. Several studies demonstrate that changes in vegetation surrounding rivers, streams and brooks affect the associated araneofauna. The aim of this research was to compare differences found in diversity (abundance and richness, composition and phenology of Araneidae spiders sampled in different habitats in four riparian forest catchments in southern Brazil. Samples were taken from riparian forests in four rivers of Rio Grande do Sul State: Piratini, Camaquã, Sinos and Maquiné rivers, each in a different hydrographic basin. Samples were taken twice seasonally on each basin during two years, sampling the araneofauna of the tree-shrub strata with beating tray. Six transects were employed on each basin, two per habitat: edge with grassland, forest interior and river edge. Araneids totalled 20 genera and 65 species. Comparing riparian forests significant differences are found. Spider abundance differed among riparian forests as well as species richness. Overall, Piratini river riparian forest had the higher abundance and richness for Araneidae; the lower values were in Sinos river forest. The stronger degradation and fragmentation of the riparian forests of Sinos river probably influenced the results, with human disturbance gradients associated negatively to web building. We present data on the diversity of these spiders, which were very abundant in the riparian forest interior and very rich in species in the grassland/riparian forest edge. Species composition also differs among the studied habitats (the above plus river/riparian forest edge. For the most abundant species the phenological pattern across the seasons was also analysed.

  2. Mapping of riparian invasive species with supervised classification of Unmanned Aerial System (UAS) imagery

    Science.gov (United States)

    Michez, Adrien; Piégay, Hervé; Jonathan, Lisein; Claessens, Hugues; Lejeune, Philippe

    2016-02-01

    Riparian zones are key landscape features, representing the interface between terrestrial and aquatic ecosystems. Although they have been influenced by human activities for centuries, their degradation has increased during the 20th century. Concomitant with (or as consequences of) these disturbances, the invasion of exotic species has increased throughout the world's riparian zones. In our study, we propose a easily reproducible methodological framework to map three riparian invasive taxa using Unmanned Aerial Systems (UAS) imagery: Impatiens glandulifera Royle, Heracleum mantegazzianum Sommier and Levier, and Japanese knotweed (Fallopia sachalinensis (F. Schmidt Petrop.), Fallopia japonica (Houtt.) and hybrids). Based on visible and near-infrared UAS orthophoto, we derived simple spectral and texture image metrics computed at various scales of image segmentation (10, 30, 45, 60 using eCognition software). Supervised classification based on the random forests algorithm was used to identify the most relevant variable (or combination of variables) derived from UAS imagery for mapping riparian invasive plant species. The models were built using 20% of the dataset, the rest of the dataset being used as a test set (80%). Except for H. mantegazzianum, the best results in terms of global accuracy were achieved with the finest scale of analysis (segmentation scale parameter = 10). The best values of overall accuracies reached 72%, 68%, and 97% for I. glandulifera, Japanese knotweed, and H. mantegazzianum respectively. In terms of selected metrics, simple spectral metrics (layer mean/camera brightness) were the most used. Our results also confirm the added value of texture metrics (GLCM derivatives) for mapping riparian invasive species. The results obtained for I. glandulifera and Japanese knotweed do not reach sufficient accuracies for operational applications. However, the results achieved for H. mantegazzianum are encouraging. The high accuracies values combined to

  3. Riparian litter inputs to streams in the central Oregon Coast Range

    Science.gov (United States)

    Hart, Stephanie K.; Hibbs, David E.; Perakis, Steven S.

    2013-01-01

    Riparian-zone vegetation can influence terrestrial and aquatic food webs through variation in the amount, timing, and nutritional content of leaf and other litter inputs. We investigated how riparian-forest community composition, understory density, and lateral slope shaped vertical and lateral litter inputs to 16 streams in the Oregon Coast Range. Riparian forests dominated by deciduous red alder delivered greater annual vertical litter inputs to streams (504 g m−2 y−1) than did riparian forests dominated by coniferous Douglas-fir (394 g m−2 y−1). Deciduous forests also contributed greater lateral litter inputs per meter of stream bank on one side (109 g m−1 y−1) than did coniferous forests (63 g m−1 y−1). Total litter inputs from deciduous forests exceeded those from coniferous forests most strongly in November, coincident with an autumn peak in litter inputs. Lateral litter inputs contributed most to total inputs during winter in both forest types. Annual lateral litter movement increased with slope at deciduous sites, but only in spring/summer months at coniferous sites. Neither experimental removal of understory vegetation nor installation of mesh fences to block downslope litter movement affected lateral litter inputs to streams, suggesting that ground litter moves litter fractions were higher at deciduous sites and, when combined with greater litter amounts, yielded twice as much total litter N flux to streams in deciduous than coniferous sites. The presence of red alder in riparian forests along many small streams of the deeply incised and highly dendritic basins of the Oregon Coast Range enhances total fluxes and seasonality of litter delivery to both terrestrial and aquatic food webs in this region and complements the shade and large woody debris provided by large coniferous trees.

  4. The use of stable oxygen isotope (18O) to trace the distribution and uptake of water in riparian woodlands

    International Nuclear Information System (INIS)

    Streamside vegetation forming narrow 'corridors' in temperate regions, is typically dominated by deciduous tree species reflecting strong influences by human activities. Riparian woodlands depend on hydrological resources and have to adapt to rigid changes in water levels and soil moisture conditions. Three main water sources are typically present in the riparian zone: river water originating in the mountains, ground water and rainfall. Stable isotopes, such as oxygen-18, are useful tools which allow for water movement to be traced within the riparian zone and which help to identify water sources utilised by the trees growing in these areas. (author)

  5. Assessment of the contamination of riparian soil and vegetation by trace metals--A Danube River case study.

    Science.gov (United States)

    Pavlović, P; Mitrović, M; Đorđević, D; Sakan, S; Slobodnik, J; Liška, I; Csanyi, B; Jarić, S; Kostić, O; Pavlović, D; Marinković, N; Tubić, B; Paunović, M

    2016-01-01

    The aim of this study was to assess the spatial distribution of arsenic and heavy metals (Cd, Cr, Cu Hg, Ni, Pb and Zn) in a riparian area influenced by periodical flooding along a considerable stretch of the Danube River. This screening was undertaken on soil and plant samples collected from 43 sites along 2386 km of the river, collected during the international Joint Danube Survey 3 expedition (ICPDR, 2015). In addition, data on the concentration of these elements in river sediment was used in order to describe the relationship between sediment, riparian soil and riparian plants. A significant positive correlation (Spearman r, for ppolluted in terms of the analysed elements. PMID:26184864

  6. Measuring and Monitoring HydroBiogeochemical Flux in a Forested Riparian Floodplain of the Missouri Ozarks

    Science.gov (United States)

    Chinnasamy, P.; Hubbart, J. A.

    2009-12-01

    Forested riparian buffers play a vital role in protecting riparian ecosystems from natural and anthropogenic disturbances. Quantifying effective reach and catchment scale buffer designs is critical to achieve economic and riparian wetland natural resource sustainability. Advances in management of riparian wetlands require innovative reach-scale experimental studies and subsequent improvements in riparian modeling. Riparian recommended best management practices (BMPs) in Missouri (MO) have not been validated. Studies are therefore warranted to describe subsurface interactions between the stream, hyporheic zone (HZ), and adjoining riparian wetland/floodplain. Within the HZ groundwater discharge through highly permeable Karst geology can dramatically affect water quality. The following research is on-going in the Baskett Research and Education Area (BREA), a 9.17 km2 preserved wildland watershed located 8 km east of Ashland, in the Ozark border region of south-central MO. The climate at BREA is generally described as warm, humid, and continental, with mean January and August temperatures of -2.4 °C and 24.5 °C, respectively, and 1,022 mm mean annual precipitation. Limestone geology of Ordovician and Mississippian age underlies the BREA with dominant soils of Weller silt loam and Clinkenbeard clay loam. Vegetation at the BREA consists of northern and southern division oak dominated hickory forests. BREA offers a distinct opportunity to study wildland watershed processes to validate contemporary best management practices (BMP) in MO. To quantify hydrobiogeochemical flux, spatial and temporal (3 water years) variability in stream water temperatures, key nutrients (NO3, P, K, NH3) and hyporheic exchange are being monitored. Key hydrologic variables approaching a mass balance, plus groundwater monitoring (via piezometric arrays) are being studied. Results (beginning summer and fall 2009) will provide the necessary information to quantify the relationships between

  7. Evapotranspiration Rates of Riparian Forests, Platte River, Nebraska, 2002-06

    Science.gov (United States)

    Landon, Matthew K.; Rus, David L.; Dietsch, Benjamin J.; Johnson, Michaela R.; Eggemeyer, Kathleen D.

    2009-01-01

    Evapotranspiration (ET) in riparian areas is a poorly understood component of the regional water balance in the Platte River Basin, where competing demands have resulted in water shortages in the ground-water/surface-water system. From April 2002 through March 2006, the U.S. Geological Survey, Nebraska Platte River Cooperative Hydrology Study Group, and Central Platte Natural Resources District conducted a micrometeorological study of water and energy balances at two sites in central Nebraska near Odessa and Gothenburg to improve understanding of ET rates and factors affecting them in Platte River riparian forests. A secondary objective of the study was to constrain estimates of ground-water use by riparian vegetation to satisfy ET consumptive demands, a useful input to regional ground-water flow models. Both study sites are located on large islands within the Platte River characterized by a cottonwood-dominated forest canopy on primarily sandy alluvium. Although both sites are typical of riparian forests along the Platte River in Nebraska, the Odessa understory is dominated by deciduous shrubs, whereas the Gothenburg understory is dominated by eastern redcedars. Additionally, seasonal ground-water levels fluctuated more at Odessa than at Gothenburg. The study period of April 2002 through March 2006 encompassed precipitation conditions ranging from dry to wet. This study characterized the components of the water balance in the riparian zone of each site. ET was evaluated from eddy-covariance sensors installed on towers above the forest canopy at a height of 26.1 meters. Precipitation was measured both above and below the forest canopy. A series of sensors measured soil-moisture availability within the unsaturated zone in two different vertical profiles at each site. Changes in ground-water altitude were evaluated from piezometers. The areal footprint represented in the water balance extended up to 800 meters from each tower. During the study, ET was less variable

  8. Impact of Temporal and Spatial Variations in agrochemical Fluxes within the Riparian Buffer on Exports from a First Order Watershed

    Science.gov (United States)

    Both agricultural nitrogen and metolachlor ethane sulfonic acid (MESA), a prevalent metabolite of metolachlor, are primarily delivered to streams via groundwater flows. The ability of riparian ecosystems to remove agrochemicals from exfiltrating groundwater is a potentially important control on the...

  9. Hydrological connectivity inferred from diatom transport through the riparian-stream system

    Science.gov (United States)

    Martínez-Carreras, N.; Wetzel, C. E.; Frentress, J.; Ector, L.; McDonnell, J. J.; Hoffmann, L.; Pfister, L.

    2015-07-01

    Diatoms (Bacillariophyta) are one of the most common and diverse algal groups (ca. 200 000 species, ≈ 10-200 μm, unicellular, eukaryotic). Here we investigate the potential of aerial diatoms (i.e. diatoms nearly exclusively occurring outside water bodies, in wet, moist or temporarily dry places) to infer surface hydrological connectivity between hillslope-riparian-stream (HRS) landscape units during storm runoff events. We present data from the Weierbach catchment (0.45 km2, northwestern Luxembourg) that quantify the relative abundance of aerial diatom species on hillslopes and in riparian zones (i.e. surface soils, litter, bryophytes and vegetation) and within streams (i.e. stream water, epilithon and epipelon). We tested the hypothesis that different diatom species assemblages inhabit specific moisture domains of the catchment (i.e. HRS units) and, consequently, the presence of certain species assemblages in the stream during runoff events offers the potential for recording whether there was hydrological connectivity between these domains or not. We found that a higher percentage of aerial diatom species was present in samples collected from the riparian and hillslope zones than inside the stream. However, diatoms were absent on hillslopes covered by dry litter and the quantities of diatoms (in absolute numbers) were small in the rest of hillslope samples. This limits their use for inferring hillslope-riparian zone connectivity. Our results also showed that aerial diatom abundance in the stream increased systematically during all sampled events (n = 11, 2011-2012) in response to incident precipitation and increasing discharge. This transport of aerial diatoms during events suggested a rapid connectivity between the soil surface and the stream. Diatom transport data were compared to two-component hydrograph separation, and end-member mixing analysis (EMMA) using stream water chemistry and stable isotope data. Hillslope overland flow was insignificant during

  10. Analyzing riparian forest cover changes along the Firniz River in the Mediterranean City of Kahramanmaras in Turkey.

    Science.gov (United States)

    Akay, Abdullah E; Sivrikaya, Fatih; Gulci, Sercan

    2014-05-01

    Riparian forests adjacent to surface water are important transitional zones which maintain and enrich biodiversity and ensure the sustainability in a forest ecosystem. Also, riparian forests maintain water quality, reduce sediment delivery, enhance habitat areas for aquatic life and wildlife, and provide ecological corridors between the upland and the downstream. However, the riparian ecosystems have been degraded mainly due to human development, forest operations, and agricultural activities. In order to evaluate the impacts of these factors on riparian forests, it is necessary to estimate trends in forest cover changes. This study aims to analyze riparian forest cover changes along the Firniz River located in Mediterranean city of Kahramanmaras in Turkey. Changes in riparian forest cover from 1989 to 2010 have been determined by implementing supervised classification method on a series of Landsat TM imagery of the study area. The results indicated that the classification process applied on 1989 and 2010 images provided overall accuracy of 80.08 and 75 %, respectively. It was found that the most common land use class within the riparian zone was productive forest, followed by degraded forest, agricultural areas, and other land use classes. The results also indicated that the areas of degraded forest and forest openings increased, while productive forest and agricultural areas decreased between the years of 1989 and 2010. The amount of agricultural areas decreased due to the reduction in the population of rural people. According to these results, it can be concluded that special forest management and operation techniques should be implemented to restore the forest ecosystem in riparian areas. PMID:24338054

  11. Assessing the Potential Impacts to Riparian Ecosystems Resulting from Hemlock Mortality in Great Smoky Mountains National Park

    OpenAIRE

    Scott W. Roberts; Tankersley, Roger; Orvis, Kenneth H.

    2009-01-01

    Hemlock Woolly Adelgid (Adelges tsugae) is spreading across forests in eastern North America, causing mortality of eastern hemlock (Tsuga canadensis [L.] Carr.) and Carolina hemlock (Tsuga caroliniana Engelm.). The loss of hemlock from riparian forests in Great Smoky Mountains National Park (GSMNP) may result in significant physical, chemical, and biological alterations to stream environments. To assess the influence of riparian hemlock stands on stream conditions and estimate possible impact...

  12. Spatial and temporal mapping of shallow groundwater tables in the riparian zone of a Swedish headwater catchment

    OpenAIRE

    Hellstrand, Eva

    2012-01-01

    Understanding the hydrology of the riparian zone in a catchment can be an important prerequisite for determining solute loads and concentrations in streams. The riparian zone is the transition zone between surrounding landscape and an open water stream. This study focuses on the spatial and temporal variations of shallow groundwater levels in a forested headwater catchment in the Bergslagen area of central Sweden. Three snapshot campaigns were conducted during dry, humid and wet conditions to...

  13. Vulnerability of riparian ecosystems to elevated CO2 and climate change in arid and semiarid western North America

    Science.gov (United States)

    Perry, Laura G.; Andersen, Douglas C.; Reynolds, Lindsay V.; Nelson, S. Mark; Shafroth, Patrick B.

    2012-01-01

    Riparian ecosystems, already greatly altered by water management, land development, and biological invasion, are being further altered by increasing atmospheric CO2 concentrations ([CO2]) and climate change, particularly in arid and semiarid (dryland) regions. In this literature review, we (1) summarize expected changes in [CO2], climate, hydrology, and water management in dryland western North America, (2) consider likely effects of those changes on riparian ecosystems, and (3) identify critical knowledge gaps. Temperatures in the region are rising and droughts are becoming more frequent and intense. Warmer temperatures in turn are altering river hydrology: advancing the timing of spring snow melt floods, altering flood magnitudes, and reducing summer and base flows. Direct effects of increased [CO2] and climate change on riparian ecosystems may be similar to effects in uplands, including increased heat and water stress, altered phenology and species geographic distributions, and disrupted trophic and symbiotic interactions. Indirect effects due to climate-driven changes in streamflow, however, may exacerbate the direct effects of warming and increase the relative importance of moisture and fluvial disturbance as drivers of riparian ecosystem response to global change. Together, climate change and climate-driven changes in streamflow are likely to reduce abundance of dominant, native, early-successional tree species, favor herbaceous species and both drought-tolerant and late-successional woody species (including many introduced species), reduce habitat quality for many riparian animals, and slow litter decomposition and nutrient cycling. Climate-driven changes in human water demand and associated water management may intensify these effects. On some regulated rivers, however, reservoir releases could be managed to protect riparian ecosystem. Immediate research priorities include determining riparian species' environmental requirements and monitoring riparian

  14. Contribution of Wetland Resources to Household Incomes of Riparian Communities of Katonga Wetland in Mpigi District, Uganda

    OpenAIRE

    E. Kateyo; P. Nsereko; Kansiime, F.

    2014-01-01

    Katonga wetland which lies to the western part of Lake Victoria covers an area of 237.4 km2. Although the wetland is known to contain flora and fauna that support livelihoods, there has been lack of information on the economic value of these resources and their contribution to livelihoods particularly of the rural riparian communities. The objective of the study was to generate information on the vital wetland resources, the economic value and contribution of these resources to riparian commu...

  15. Technical Note: Linking soil – and stream-water chemistry based on a riparian flow-concentration integration model

    OpenAIRE

    J. Seibert; T. Grabs; Köhler, S; H. Laudon; Winterdahl, M.; Bishop, K.

    2009-01-01

    The riparian zone, the last few meters of soil through which water flows before entering the stream, has been identified as a first order control on key aspects of stream water chemistry dynamics. We propose that the vertical distribution of lateral water flow across the profile of soil water chemistry in the riparian zone provides a conceptual explanation of how this control functions in catchments where matrix flow predominates. This paper presents a mathematical implementation of this conc...

  16. Classification of riparian forest species and health condition using multi-temporal and hyperspatial imagery from unmanned aerial system

    OpenAIRE

    Michez, Adrien; Piégay, Hervé; Lisein, Jonathan; Claessens, Hugues; Lejeune, Philippe

    2016-01-01

    Riparian forests are critically endangered many anthropogenic pressures and natural hazards. The importance of riparian zones has been acknowledged by European Directives, involving multi-scale monitoring. The use of this very high resolution and hyperspatial imagery in a multi-temporal approach is an emerging topic. The trend is reinforced by the recent and rapid growth of the use of the unmanned aerial system (UAS), which has prompted the development of innovative methodology. Our study pro...

  17. Controls on the spatial and temporal variability of Rn-222 in riparian groundwater in a lowland Chalk catchment.

    OpenAIRE

    Mullinger, Neil J.; Pates, Jackie M.; Binley, Andrew M.; Crook, N. P.

    2009-01-01

    Radon is a powerful tracer of stream-aquifer interactions. However, it is important to consider the source and behaviour of radon in groundwater when interpreting observations of river radon in relation to groundwater discharge. Here we characterise the variability in groundwater radon concentrations in the riparian zone of a Chalk catchment. Groundwater 222Rn (radon) concentrations were determined in riparian zone boreholes at two sites in the Lambourn catchment, Berkshire, UK, over a two ye...

  18. Biodiversity and Phytosociological Studies of Upstream and Downstream Riparian Areas of Pakistan: Special Reference to Taunsa Wildlife Sanctuary and Keti Shah Forests

    International Nuclear Information System (INIS)

    Pakistan riparian zone mostly belongs to Sindh and Punjab provinces and prone to climatic problems and anthropogenic activities. The research was conduct to estimate and compare the structure and composition of riverine floral diversity in low riparian zone of River Indus. The data was collected from Keti Shah forest and Taunsa wildlife sanctuary. Total 14259 plants/individuals were recorded, which belong to 54 plant species with 18 different families. In Taunsa pre-monsoon survey, total 30 plant species were found with 4476 plants from 16 different families. In Taunsa post-monsoon survey total 3348 individuals were recorded from 20 plant species and 9 families. Similarly, in Keti Shah forest, total 3975 individual were recorded from 22 species and 11 families during the pre-monsoon season and 2460 plants were recorded in post-monsoon season, belonging to 16 species and 10 families. These species mostly belong to Fabaceae, Poaceae, Cyperaceae and Asclepiadaceae. Different phytosociological parameters indicate Tamarix dioca, Cynodon dactylon, Desmostachya bipinnata, Imperata cylindrica, Fimbristylis hispidula, Acacia nilotica, Phragmites karka, Tamarix sp. and Saccharum bengalense as dominant species. The biodiversity in upstream and downstream areas were rich in pre-monsoon season in comparison to post-monsoon season in surveyed areas. This study is useful for management of the area in the future as conservation strategies can be made through considering the adaptive tree species in future plantation and endangered species can be conserved. (author)

  19. Multiscale remote sensing analysis to monitor riparian and upland semiarid vegetation

    Science.gov (United States)

    Nguyen, Uyen

    The health of natural vegetation communities is of concern due to observed changes in the climatic-hydrological regime and land cover changes particularly in arid and semiarid regions. Monitoring vegetation at multi temporal and spatial scales can be the most informative approach for detecting change and inferring causal agents of change and remediation strategies. Riparian communities are tightly linked to annual stream hydrology, ground water elevations and sediment transport. These processes are subject to varying magnitudes of disturbance overtime and are candidates for multi-scale monitoring. My first research objective focused on the response of vegetation in the Upper San Pedro River, Arizona, to reduced base flows and climate change. I addressed the correlation between riparian vegetation and hydro-climate variables during the last three decades in one of the remaining undammed rivers in the southwestern U.S. Its riparian forest is threatened by the diminishing base flows, attributed by different studies either to increases in evapotranspiration (ET) due to conversion of grasslands to mesquite shrublands in the adjacent uplands, or to increased regional groundwater pumping to serve growing populations in surrounding urban areas and or to some interactions of those causes. Landsat 5 imagery was acquired for pre- monsoon period, when riparian trees had leafed out but before the arrival of summer monsoon rains in July. The result has showed Normalized Difference Vegetation Index (NDVI) values from both Landsat and Moderate Resolution Imaging Spectrometer (MODIS) had significant decreases which positively correlated to river flows, which decreased over the study period, and negatively correlated with air temperatures, which have increased by about 1.4°C from 1904 to the present. The predictions from other studies that decreased river flows could negatively impact the riparian forest were supported by this study. The pre-monsoon Normalized Different Vegetation

  20. Applications of Remote Sensing and GIS to the Assessment of Riparian Zones for Environmental Restoration in Agricultural Watersheds

    Institute of Scientific and Technical Information of China (English)

    GU Fengxia; LIU Wenbao

    2010-01-01

    Geographical design of riparian buffers with long-term vegetation cover for environmental restoration in agricul turalwatersheds needs to assess how much farmland is located in the buffers of a concerned watershed. Traditionally, this assessment was done by field surveying and manual mapping, which was a time-consuming and costly process for a large region. In this paper,remote sensing (RS) and geographical information system (GIS) as cost-effective techniques were used to develop a catchments-based approach for identifying critical sites of agricultural riparian buffer restoration. The method was explained through a case study of watershed with 11 catchments and results showed that only four of the catchments were eligible in terms of higher priority for riparian buffer restoration. This research has methodological contributions to the spatial assessment of farming intensities in catchments-based riparian buffers across a watershed and to the geographical designs of variable buffering scenarios within catchments. The former makes the catchments-based management strategy possible, and the latter provides alternative restoration scenarios to meet different management purposes, both of which have direct implementations to the environmental restoration of riparian buffers in the real world. This study, thus, highlights the great potential of RS and GIS applications to the planning and management of riparian buffer restoration in agricultural watersheds.

  1. Surface Layer Flux Processes During Cloud Intermittency and Advection above a Middle Rio Grande Riparian Forest, New Mexico

    Science.gov (United States)

    Cleverly, J. R.; Prueger, J.; Cooper, D. I.; Hipps, L.; Eichinger, W.

    2002-12-01

    An intensive field campaign was undertaken to bring together state-of-the-art methodologies for investigating surface layer physical characteristics over a desert riparian forest. Three-dimensional sonic eddy covariance (3SEC), LIDAR, SODAR, Radiosonde, one-dimensional propeller eddy covariance (1PEC), heat dissipation sap flux, and leaf gas exchange were simultaneously in use 13 -- 21 June 1999 at Bosque del Apache National Wildlife Refuge (NWR) in New Mexico. A one hour period of intense advection was identified by /line{v} >> 0 and /line{u} = 0, indicating that wind direction was transverse to the riparian corridor. The period of highest /line{v} was 1400 h on 20 June; this hour experienced intermittent cloud cover and enhanced mesoscale forcing of surface fluxes. High-frequency (20 Hz) time series of u, v, w, q, θ , and T were collected for spectral, cospectral, and wavelet analyses. These time series analyses illustrate scales at which processes co-occur. At high frequencies (> 0.015 Hz), /line{T' q'} > 0, and (KH)/ (KW) = 1. At low frequencies, however, /line{T' q'} < 0, and (KH)/(KW) !=q 1. Under these transient conditions, frequencies below 0.015 Hz are associated with advection. While power cospectra are useful in associating processes at certain frequencies, further analysis must be performed to determine whether such examples of aphasia are localized to transient events or constant through time. Continuous wavelet transformation (CWT) sacrifices localization in frequency space for localization in time. Mother wavelets were evaluated, and Daubechies order 10 wavelet was found to reduce red noise and leakage near the spectral gap. The spectral gap is a frequency domain between synoptic and turbulent scales. Low frequency turbulent structures near the spectral gap in the time series of /line{T' q'}, /line{w' T'}, and /line{w' q'} followed a perturbation--relaxation pattern to cloud cover. Further cloud cover in the same hour did not produce the low

  2. Improving the quantification of land cover pressure on stream ecological status at the riparian scale using High Spatial Resolution Imagery

    Science.gov (United States)

    Tormos, T.; Kosuth, P.; Durrieu, S.; Villeneuve, B.; Wasson, J. G.

    The aim of this paper is to demonstrate the interest of High Spatial Resolution Imagery (HSRI) and the limits of coarse land cover data such as CORINE Land Cover (CLC), for the accurate characterization of land cover structure along river corridors and of its functional links with freshwater ecological status on a large scale. For this purpose, we compared several spatial indicators built from two land cover maps of the Herault River corridor (southern France): one derived from the CLC database, the other derived from HSRI. The HSRI-derived map was obtained using a supervised object-based classification of multi-source remotely-sensed images (SPOT 5 XS-10 m and aerial photography-0.5 m) and presents an overall accuracy of 70%. The comparison between the two sets of spatial indicators highlights that the HSRI-derived map allows more accuracy in the quantification of land cover pressures near the stream: the spatial structure of the river landscape is finely resolved and the main attributes of riparian vegetation can be quantified in a reliable way. The next challenge will consist in developing an operational methodology using HSRI for large-scale mapping of river corridor land cover, for spatial indicator computation and for the development of related pressure/impact models, in order to improve the prediction of stream ecological status.

  3. 淮河干流岸边带生态健康遥感评估%Remote sensing assessment of ecological health of the riparian buffer along Huaihe River

    Institute of Scientific and Technical Information of China (English)

    殷守敬; 吴传庆; 王晨; 马万栋; 何游云

    2016-01-01

    结合高分辨率遥感影像在岸边带范围提取、生态系统高精度分类、生态结构特征提取方面的优势,将景观结构指数纳入岸边带生态健康评估指标体系,从生态功能、生态结构和生态胁迫三个方面对淮河干流岸边带生态健康状况进行全面调查评估.评价结果显示,淮河干流岸边带生态健康指数低于0.3,生态健康状况总体处于较差水平,并具有明显的空间走向特征,从上游到中游呈现出生态环境状况逐渐变差、再略有改善的趋势.通过对淮河干流岸边带生态环境问题的分析,认为人类开发强度大、植被覆盖率低、自然岸线保有率低、人为干扰强度大是造成淮河干流岸边带生态健康状况较差的主要原因.%This study introduces landscape structure indices into the ecological assessment system of riparian health, taking advantage of remote sensing capabilities in the derivation of riparian zone, feature extraction of ecological structure, and high-precision classification of ecological system. An overall ecological investigation and assessment of riparian health along Huaihe River was carried out from the aspects of ecological function, ecosystem structure and ecological stress. The results showed that the health of riparian ecology along Huaihe River was generally poor, with an ecological health index less than 0.3. A significant spatial characteristic was shown that the ecological environment gradually became worse from upstream to midstream and then slightly improved. Intensive human development, low vegetation coverage, low natural shoreline rate and high human disturbance were identified as the main cause of the bad ecological condition of the riparian zone along Huaihe River, according to the analysis of ecological and environmental problems.

  4. Noise-driven cooperative dynamics between vegetation and topography in riparian zones

    Science.gov (United States)

    Vesipa, R.; Camporeale, C.; Ridolfi, L.

    2015-10-01

    Riparian ecosystems exhibit complex biotic and abiotic dynamics, where the triad vegetation-sediments-stream determines the ecogeomorphological features of the river landscape. Random fluctuations of the water stage are a key trait of this triad, and a number of behaviors of the fluvial environment can be understood only taking into consideration the role of noise. In order to elucidate how randomness shape riparian transects, a stochastic model that takes into account the main links between vegetation, sediments, and the stream is adopted, emphasizing the capability of vegetation to alter the plot topography. A minimalistic approach is pursued, and the probability density function of vegetation biomass is analytically evaluated in any transect plot. This probability density function strongly depends on the vegetation-topography feedback. We demonstrate how the vegetation-induced modifications of the bed topography create more suitable conditions for the survival of vegetation in a stochastically dominated environment.

  5. Restoration of Riparian Areas Following the Removal of Cattle in the Northwestern Great Basin

    Science.gov (United States)

    Batchelor, Jonathan L.; Ripple, William J.; Wilson, Todd M.; Painter, Luke E.

    2015-04-01

    We assessed the effects of the elimination of livestock in riparian systems at Hart Mountain National Antelope Refuge in southeastern Oregon, 23 years after the removal of cattle grazing, using 64 photos taken before grazing was removed compared with later retake photos. Two methods were used for this assessment: (1) a qualitative visual method comparing seven cover types and processes and (2) a new quantitative method of inserting digital line transects into photos. Results indicated that channel widths and eroding banks decreased in 64 and 73 % of sites, respectively. We found a 90 % decrease in the amount of bare soil ( P line transects into photo pairs. An overall accuracy of 91 % (kappa 83 %) suggests that digital line transects can be a useful tool for quantifying vegetation cover from photos. Our results indicate that the removal of cattle can result in dramatic changes in riparian vegetation, even in semi-arid landscapes and without replanting or other active restoration efforts.

  6. Valuing Riparian Forests Restoration: a CVM Application in Corumbatai River Basin

    OpenAIRE

    Caetano Brugnaro

    2010-01-01

    This study is an application of CVM to a specific area in Brazil, the Corumbatai river basin, in the state of Sao Paulo, aiming to estimate the value attached by affected people to a hypothetical riparian forest restoration project. The method used was the double bounded dichotomous choice under a logit model. Data were obtained by street-intercept interviews with a net sample of 930 individuals, 20 years or older, living in seven municipalities (cities and respective rural areas) that contai...

  7. Object-based class modelling for multi-scale riparian forest habitat mapping

    Science.gov (United States)

    Strasser, Thomas; Lang, Stefan

    2015-05-01

    Object-based class modelling allows for mapping complex, hierarchical habitat systems. The riparian zone, including forests, represents such a complex ecosystem. Forests within riparian zones are biologically high productive and characterized by a rich biodiversity; thus considered of high community interest with an imperative to be protected and regularly monitored. Satellite earth observation (EO) provides tools for capturing the current state of forest habitats such as forest composition including intermixture of non-native tree species. Here we present a semi-automated object based image analysis (OBIA) approach for the mapping of riparian forests by applying class modelling of habitats based on the European Nature Information System (EUNIS) habitat classifications and the European Habitats Directive (HabDir) Annex 1. A very high resolution (VHR) WorldView-2 satellite image provided the required spatial and spectral details for a multi-scale image segmentation and rule-base composition to generate a six-level hierarchical representation of riparian forest habitats. Thereby habitats were hierarchically represented within an image object hierarchy as forest stands, stands of homogenous tree species and single trees represented by sunlit tree crowns. 522 EUNIS level 3 (EUNIS-3) habitat patches with a mean patch size (MPS) of 12,349.64 m2 were modelled from 938 forest stand patches (MPS = 6868.20 m2) and 43,742 tree stand patches (MPS = 140.79 m2). The delineation quality of the modelled EUNIS-3 habitats (focal level) was quantitatively assessed to an expert-based visual interpretation showing a mean deviation of 11.71%.

  8. Estimating Riparian and Agricultural Actual Evapotranspiration by Reference Evapotranspiration and MODIS Enhanced Vegetation Index

    OpenAIRE

    Scott, Russell L.; Uyen Nguyen; Glenn, Edward P; Pamela L. Nagler; Tanya Doody

    2013-01-01

    Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ETa) based on the Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectrometer (MODIS) sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ETo). The algorith...

  9. Collembola, Protura and Pauropoda in a riparian forest - mesic forest ecotone

    Czech Academy of Sciences Publication Activity Database

    Rusek, Josef; Reithofer, D.; Schmid, S.; Truxa, Ch.; Weber, J.; Wilde, U.

    České Budějovice: Biology Centre ASCR , v.v , Institute of Soil Biology, 2007. s. 57. [Central European Workshop on Soil Zoology /9./. 17.04.2007-20.04.2007, České Budějovice] Institutional research plan: CEZ:AV0Z60660521 Keywords : soil microorganisms * riparian forest * mesic forest ecotone Subject RIV: EH - Ecology, Behaviour

  10. Ecosystem response to removal of exotic riparian shrubs and a transition to upland vegetation

    Science.gov (United States)

    Reynolds, Lindsay V.; Cooper, David J.

    2011-01-01

    Understanding plant community change over time is essential for managing important ecosystems such as riparian areas. This study analyzed historic vegetation using soil seed banks and the effects of riparian shrub removal treatments and channel incision on ecosystem and plant community dynamics in Canyon de Chelly National Monument, Arizona. We focused on how seeds, nutrients, and ground water influence the floristic composition of post-treatment vegetation and addressed three questions: (1) How does pre-treatment soil seed bank composition reflect post-treatment vegetation composition? (2) How does shrub removal affect post-treatment riparian vegetation composition, seed rain inputs, and ground water dynamics? and (3) Is available soil nitrogen increased near dead Russian olive plants following removal and does this influence post-treatment vegetation? We analyzed seed bank composition across the study area, analyzed differences in vegetation, ground water levels, and seed rain between control, cut-stump and whole-plant removal areas, and compared soil nitrogen and vegetation near removed Russian olive to areas lacking Russian olive. The soil seed bank contained more riparian plants, more native and fewer exotic plants than the extant vegetation. Both shrub removal methods decreased exotic plant cover, decreased tamarisk and Russian olive seed inputs, and increased native plant cover after 2 years. Neither method increased ground water levels. Soil near dead Russian olive trees indicated a short-term increase in soil nitrogen following plant removal but did not influence vegetation composition compared to areas without Russian olive. Following tamarisk and Russian olive removal, our study sites were colonized by upland plant species. Many western North American rivers have tamarisk and Russian olive on floodplains abandoned by channel incision, river regulation or both. Our results are widely applicable to sites where drying has occurred and vegetation

  11. Hydrological Characterization of A Riparian Vegetation Zone Using High Resolution Multi-Spectral Airborne Imagery

    OpenAIRE

    Akasheh, Osama Zaki

    2008-01-01

    The Middle Rio Grande River (MRGR) is the main source of fresh water for the state of New Mexico. Located in an arid area with scarce local water resources, this has led to extensive diversions of river water to supply the high demand from municipalities and irrigated agricultural activities. The extensive water diversions over the last few decades have affected the composition of the native riparian vegetation by decreasing the area of cottonwood and coyote willow and increasing the spread o...

  12. Groundwater phosphate dynamics in a river riparian zone: effects of hydrologic flowpaths, lithology and redox chemistry

    Science.gov (United States)

    Carlyle, G. C.; Hill, A. R.

    2001-07-01

    This study examines the influence of riparian zone hydrology, lithology and redox chemistry on groundwater phosphate dynamics. Patterns of soluble reactive phosphorus (SRP), dissolved oxygen (DO) and ferrous iron (Fe 2+) in combination with hydrologic data and sediment characteristics were studied in a forested floodplain connected to a large upland sand aquifer in an agricultural region of southern Ontario, Canada. Groundwater discharge from the upland aquifer flowed laterally beneath peat in a 2-4 m thick zone of permeable sands across the floodplain to the river. Within the sands, low SRP concentrations (3 mg L -1 and Fe 2+ concentrations <0.2 mg L -1 which extended for a horizontal distance of 100-140 m across the riparian zone. High SRP concentrations (50-950 μg L -1) were associated with low DO and high Fe 2+ concentrations which exceeded 1 mg L -1 in buried channel sediments near the river bank. Sediment P fractionation indicated that the buried channel sediments contained a much higher pool of total P and Fe+Al-P than the sands. Groundwater SRP concentrations at the river bank were 25-80 μg L -1 compared to <10 μg L -1 in river water indicating that the floodplain was a source of SRP to the river. Areas of elevated SRP and Fe 2+ within the floodplain expanded in August when DO concentrations in groundwater were lower than in late spring or autumn. These data suggest that the microbial reduction of Fe 3+ to soluble Fe 2+ in anaerobic conditions influences groundwater SRP concentrations in the riparian zone. This study shows that well-organized patterns of groundwater SRP concentrations occur in riparian zones which reflect the interaction of hydrologic flowpaths and environments of different redox state. Internal sources of P associated with buried channel sediments can also influence subsurface SRP transport and release to streams.

  13. INTEGRATION OF THE MODELS OF ANNAGNPS AND REMM TO ASSESS RIPARIAN BUFFER SYSTEM FOR SEDIMENT REDUCTION

    Institute of Scientific and Technical Information of China (English)

    Yongping YUAN; Ronald BINGNER; Randall WILLIAMS; Richard LOWRANCE; David BOSCH; Joe SHERIDAN

    2007-01-01

    The United States Department of Agriculture (USDA) Annualized Agricultural Non-Point Source Pollution model (AnnAGNPS) is used to help evaluate a watershed response to agricultural management practices to control water quality. However, AnnAGNPS version 3.5 does not contain features to estimate the effect of a riparian buffer (RB) system on water quality. The Riparian Ecosystem Management Model (REMM) is used to simulate the impact of riparian buffer systems on water quality. However, frequently the lack of measured upland loadings that are required by REMM simulation limits the application of REMM. To address this data gap, a study was conducted to integrate AnnAGNPS with REMM for RB system simulation. AnnAGNPS was used to simulate water and sediment loadings from an upland field into a three-zone RB system at the Gibbs Farm located in the Georgia coastal plain. These AnnAGNPS outputs were used as the inputs to REMM. REMM was used to simulate water and sediment movement along the riparian buffers. The AnnAGNPS simulated amount of annual runoff at the edge of the field was close to observed amounts (Nash-Sutcliffe efficiency of 0.92). It is believed that a substantial portion of sand was removed from the runoff one meter into the grass buffer where the samplers were located; therefore, sand was excluded from the AnnAGNPS simulation for comparison with observed sediment. Excluding sand, the AnnAGNPS predicted amount of annual sediment matches the observed amount fairly well (Nash-Sutcliffe efficiency of 0.46). In addition, based on evaluating the percent reduction of sediment at each zonal interface, the AnnAGNPS/REMM model well simulated the function of the RB system to reduce sediment.

  14. Riparian buffer strips as a multifunctional management tool in agricultural landscapes: Introduction to the special collection

    OpenAIRE

    Stutter, M. I.; Chardon, W.J.; B. Kronvang

    2012-01-01

    Catchment riparian areas are considered key zones to target mitigation measures aimed at interrupting the movement of diffuse substances from agricultural land to surface waters. Hence, unfertilized buffer strips have become a widely studied and implemented “edge of field” mitigation measure assumed to provide an effective physical barrier against nitrogen (N), phosphorus (P), and sediment transfer. To ease the legislative process, these buffers are often narrow mandatory strips along streams...

  15. Living on the edge : effectiveness of buffer strips in protecting biodiversity on boreal riparian forests

    OpenAIRE

    Hylander, Kristoffer

    2004-01-01

    The objective of this thesis is to evaluate the ecological consequences of buffer strip retention on riparian and terrestrial biodiversity. Earlier studies on forest buffer strips have evaluated their effectiveness in relation to water quality and aquatic biota. However, forests along streams are species rich habitats for many organism groups. Buffer strip management is assumed to be important also for protecting such species. Current approaches to biodiversity-oriented forest management prac...

  16. What are riparian ecosystems and why are we worried about them

    OpenAIRE

    Hawkins, Charles P.

    1994-01-01

    Riparian areas represent less than 2 percent of all terrestrial ecosystems, but they are functionally on of the most important features within natural landscapes. They are characterized by high biotic production and diversity; they moderate flood intensity and store water; and they maintain high water quality by acting as nutrient and sediment sinks. These ecological functions make them valuable areas for a variety of human uses including agriculture, timber and livestock production, recreati...

  17. Restoring Aspen Riparian Stands With Beaver on the Northern Yellowstone Winter Range

    OpenAIRE

    McColley, Samuel D; Tyers, Dan B; Sowell, Bok F

    2011-01-01

    Aspen (Populus tremuloides) on the Gardiner Ranger District, Gallatin National Forest, have declined over the last half-century. In an attempt to reverse this trend, beaver (Castor canadensis) were reintroduced in Eagle Creek in 1991. In 2005, we assessed the long-term effects of beaver on aspen stands and the associated riparian area in the Eagle Creek drainage. Aspen recovery was estimated by comparing vegetative changes among control sites with (n = 5), active beaver sites (n = 6), sites a...

  18. Movement of nitrogen through a riparian forest in a tropical, agricultural landscape

    OpenAIRE

    Connor, Sarah

    2012-01-01

    Riparian zones have been widely reported to function as effective buffers, removing nitrate (NO₃⁻) from groundwater before it is discharged into adjacent streams. This is particularly important in agricultural catchments where additional nitrogen (N) from fertilisers may be leached into groundwater. On coastal plains, NO₃⁻ in groundwater discharged into streams can potentially enrich coastal waters. The permanent removal of NO₃⁻ through denitrification can improve water quality, however incom...

  19. Striving for unanimity and consensus: finding the common ground in conflict over riparian management

    OpenAIRE

    Johnson, Mark L

    1994-01-01

    Dealing with natural resources conflicts creates an uncomfortable situation for many people. To successfully deal with the conflicts associated with riparian-area management, four points must be addressed: paradigms, strategic planning, decision-making, and implementation and monitoring. The paradigms of everyone involved in the resolution of the conflict must be understood. Strategic planning helps find the common ground of the people involved and reduces the misunderstandings. The decision-...

  20. Water and Energy Balance of a Riparian and Agricultural Ecosystem along the Lower Colorado River

    OpenAIRE

    Taghvaeian, Saleh

    2011-01-01

    Spatially-distributed water consumption was modeled over a segment of the Lower Colorado River, which contains irrigated agricultural and Tamarisk-dominated riparian ecosystems. For the irrigation scheme, distributed evapotranspiration data were analyzed in conjunction with point measurements of precipitation and surface flow in order to close daily and annual water balance. The annual closure error was less than 1% of the total water diversion to the area. In addition, it was found that t...

  1. Responses to river inundation pressures control prey selection of riparian beetles.

    Directory of Open Access Journals (Sweden)

    Matt J O'Callaghan

    Full Text Available BACKGROUND: Riparian habitats are subjected to frequent inundation (flooding and are characterised by food webs that exhibit variability in aquatic/terrestrial subsidies across the ecotone. The strength of this subsidy in active riparian floodplains is thought to underpin local biodiversity. Terrestrial invertebrates dominate the fauna, exhibiting traits that allow exploitation of variable aquatic subsidies while reducing inundation pressures, leading to inter-species micro-spatial positioning. The effect these strategies have on prey selection is not known. This study hypothesised that plasticity in prey choice from either aquatic or terrestrial sources is an important trait linked to inundation tolerance and avoidance. METHOD/PRINCIPAL FINDINGS: We used hydrological, isotopic and habitat analyses to investigate the diet of riparian Coleoptera in relation to inundation risk and relative spatial positioning in the floodplain. The study examined patch scale and longitudinal changes in utilisation of the aquatic subsidy according to species traits. Prey sourced from terrestrial or emerging/stranded aquatic invertebrates varied in relation to traits for inundation avoidance or tolerance strategies. Traits that favoured rapid dispersal corresponded with highest proportions of aquatic prey, with behavioural traits further predicting uptake. Less able dispersers showed minimal use of aquatic subsidy and switched to a terrestrial diet under moderate inundation pressures. All trait groups showed a seasonal shift in diet towards terrestrial prey in the early spring. Prey selection became exaggerated towards aquatic prey in downstream samples. CONCLUSIONS/SIGNIFICANCE: Our results suggest that partitioning of resources and habitat creates overlapping niches that increase the processing of external subsidies in riparian habitats. By demonstrating functional complexity, this work advances understanding of floodplain ecosystem processes and highlights the

  2. Greenhouse gas emissions from a Danish riparian wetland before and after restoration

    DEFF Research Database (Denmark)

    Audet, Joachim; Elsgaard, Lars; Kjærgaard, Charlotte;

    2013-01-01

    of greenhouse gases (GHG) such as nitrous oxide (N2O) and methane (CH4). The effect of the restoration of a Danish riparian wetland on the emission of GHG was assessed by determining the fluxes of N2O, CH4 and carbon dioxide from ecosystem respiration (Reco) prior to and after restoration of a stream...... and its adjacent riparian areas. The results collected the first year after restoration revealed spatially and seasonally variable N2O emissions ranging from 0.1 to 3.12 g N m-2 y-1 after the restoration, but no statistically significant effect of the restoration on N2O emission could be observed. The...... interaction or main effect. Nitrous oxide emission was related to T(10 cm), soil pH and soil N. Annual CH4 emissions after restoration were comparable to those of natural riparian wetland sites and the increased CH4 emission appeared to be compensated by a decrease in Reco, while the effect of the restoration...

  3. Disproportionate contribution of riparian inputs to organic carbon in freshwater systems.

    Science.gov (United States)

    Marwick, Trent Richard; Van Acker, Kristof; Darchambeau, François; Vieira Borges, Alberto; Bouillon, Steven

    2014-05-01

    A lack of appropriate proxies has traditionally hampered our ability to distinguish riverine organic carbon (OC) sources at the landscape scale. However, the dissection of tropical and sub-tropical C4 savannah grasslands by C3 riparian vegetation, and the distinct carbon stable isotope signature (δ13C) of these two photosynthetic pathways, provides a unique setting to assess the relative contribution of riparian and more distant sources to riverine C pools. Here, we show through the comparison of δ13C signatures of bulk sub-basin vegetation (δ13CVEG) with those of riverine OC pools, that in contrasting C3- and C4-dominated sub-tropical drainage basins, riverine OC is disproportionately sourced from bordering riparian vegetation, irrespective of climatic season. Our findings carry implications for the use of sedimentary δ13C signatures as proxies for past forest-grassland distribution and climate, as the C4 component may be considerably underestimated due to its disconnection from riverine OC pools.

  4. Nitrogen dynamics among cropland and riparian buffers: soil-landscape influences.

    Science.gov (United States)

    Young, Eric O; Briggs, Russell D

    2007-01-01

    Nitrate (NO3-) leaching to ground water poses water quality concerns in some settings. Riparian buffers have been advocated to reduce excess ground water NO3- concentrations. We characterized inorganic N in soil solution and shallow ground water for 16 paired cropland-riparian plots from 2003 to 2005. The sites were located at two private dairy farms in Central New York on silt and gravelly silt loam soils (Aeric Endoaqualfs, Fluvaquentic Endoaquepts, Fluvaquentic Eutrudepts, Glossaquic Hapludalfs, and Glossic Hapludalfs). It was hypothesized that cropland N inputs and soil-landscape variability would jointly affect NO3- leaching and transformations in ground water. Results showed that well and moderately well drained fields had consistently higher ground water NO3- compared to more imperfectly drained fields receiving comparable N inputs. Average 50-cm depth soil solution NO3- and ground water dissolved oxygen (DO) explained 64% of average cropland ground water NO3- variability. Cropland ground water with an average DO of organic matter. Chloride patterns indicated that dilution was minor in most buffers, suggesting that denitrification losses were important. Soil-landscape factors strongly influenced NO3- behavior and suggest the importance of accurately characterizing soil variability along cropland-riparian zones. PMID:17485712

  5. The Role of Road Corridors on Riparian Vegetation and Stream Ecosystem Dynamics.

    Science.gov (United States)

    Crowl, T.; Heartsill-Scalley, T.; Covich, A. P.; Hein, C. L.

    2005-05-01

    Stream ecosystems are dependent on organic material from the riparian zone as a major energy source for the food web. Leaf litter (organic matter) entering streams is processed by a combination of physical and biological mechanisms. In temperate streams, microbial conditioning is important for detrital processing. Much less is known in tropical systems, especially those dominated by large macro-consumers such as decapods. There is also variation among species in terms of processing rates that are explained by nutritional value, chemical defenses and palatability. These traits are a function of plant life history. If riparian species are being significantly altered through invasions by exotic species along road corridors, then we can expect changes in detrital processing rates and ultimately, ecosystem function. As part of a biocomplexity project in Puerto Rico, we are quantifying the changes to species composition and trait-mediated decomposition and foodweb dynamics. Where roads are constructed, exotic invasives include Spathodea, Bambusa, Syzigium and a various grasses. Because of the chemical defenses and their high nutritional value, decomposition rates on these species is much higher than for native riparian species. The increased breakdown rates may `accelerate' ecosystem processes and either enhance or destabilize existing food web linkages.

  6. Riparian buffer project : annual report for the period April 1, 2001 to March 31, 2002.; ANNUAL

    International Nuclear Information System (INIS)

    This project implements riparian buffer systems in the Mid-Columbia, addressing limiting factors identified in the Fifteen mile Subbasin Summary, June 30, 2000. The project is providing the technical planning support needed to implement at least 36 riparian buffer system contracts on approximately 872 acres covering an estimated 40 miles of anadromous fish streams over a three year period. In the first year of implementation, 26 buffer contracts were established on 25-26 miles of stream. This nearly doubled the annual goal. Buffer widths averaged 83 ft. on each side of the stream. Implementation included prescribed plantings, fencing, and related practices. Actual implementation costs, lease payments, and maintenance costs are borne by existing USDA programs: Conservation Reserve and Conservation Reserve Enhancement Programs. The lease period of each contract may vary between 10 to 15 years. During this year the average was 14.5 years. The total value of contracts established this year is$1,491,235 compared with$64,756 in BPA contract costs to provide the technical support needed to get the contracts implemented. This project provides technical staffing to conduct assessments and develop plans to help keep pace with the growing backlog of potential riparian buffer projects. Word of mouth from satisfied customers has brought in many new sign-ups during the year. More than half of the contracts this year have been done in the Hood and Fifteen mile sub-basins with additional contracts in adjacent sub-basins

  7. Soil Seed Bank Dynamics of a Riparian Forest and its Adjacent Upland Vegetation

    Directory of Open Access Journals (Sweden)

    Omowumi Omotoyosi OLALOYE

    2016-03-01

    Full Text Available The present study was conducted to determine the densities and soil seed bank composition of a riparian forest and its adjacent upland vegetation for a better understanding the potentials of the soil seed banks in facilitating succession towards a more natural forest of native tree species. Three contiguous 20 m x 20 m plots were systematically established on both riparian forest and upland vegetation. Species enumeration, identification and distribution into families of the standing vegetation were carried out. Furthermore, five replicates soil samples were collected at two different depths (0-15 cm, 15-30 .The seedling emergence test was carried out for six months in the greenhouse to determine the species composition and the density of the seed in both vegetation types. The results of the seedling emergence revealed that more seeds were deposited at the upper depth (0-15 cm than the lower depth 15-30 cm in the two vegetation types in both dry and rainy season. There was low similarity in species composition between the standing vegetation and soil seed bank in each of the two vegetation types. Herbaceous species recorded the highest number of seedlings as compared to the other habit. The low similarity between seed bank and standing vegetation of the riparian forest and the adjacent upland vegetation suggested that soil seed bank was insignificant in their restoration.

  8. Spatiotemporal patterns of water table fluctuations and evapotranspiration induced by riparian vegetation in a semiarid area

    Science.gov (United States)

    Yue, Weifeng; Wang, Tiejun; Franz, Trenton E.; Chen, Xunhong

    2016-03-01

    Groundwater evapotranspiration (ETg) links various ecohydrological processes and is an important component in regional water budgets. In this study, an extensive monitoring network was established in a semiarid riparian area to investigate various controls on the spatiotemporal pattern of water table fluctuations (WTFs) and ETg induced by riparian vegetation. Along a vegetation gradient (˜1200 m), diurnal WTFs were observed during a growing season in areas covered by woody species (Populus sect. Aigeiros and Juniperus virginiana) and wet slough vegetation (Panicum virgatum and Bromus inermis) with deeper root systems; whereas, no diurnal WTFs were found in the middle section with shallower-rooted grasses (Poa pratensis and Carex sp.). The occurrence of diurnal WTFs was related to temperature-controlled plant phenology at seasonal scales and to radiation at subdaily scales. Daily ETg in the mid-growing season was calculated using the White method. The results revealed that depth to water table (DTWT) was the dominant control on ETg, followed by potential evapotranspiration (ETp). By combining the effects of DTWT and ETp, it was found that at shallower depths, ETg was more responsive to changes in ETp, due to the closer linkage of land surface processes with shallower groundwater. Finally, exponential relationships between ETg/ETp and DTWT were obtained at the study site, although those relationships varied considerably across the sites. This study demonstrates the complex interactions of WTFs and ETg with surrounding environmental variables and provides further insight into modeling ETg over different time scales and riparian vegetation.

  9. Soil Quality under Riparian Forest at Different Stages of Ecological Succession and Cultivated with Sugarcane

    Science.gov (United States)

    Silva, Luiz Gabriel; Casagrande, José Carlos; Colato, Alexandre; Soares, Marcio Roberto; Perissatto Meneghin, Silvana

    2014-05-01

    This work aimed at evaluating the quality of the soil through its chemical, physical and microbiological attributes, using additive pondered model, as well as studying the characteristics of the linear method of combination of data, figures of merit (FoMs), the process of assigning weights and standard score functions, using measurements collected in three areas (two riparian forests and a commercial crop of sugarcane) in two soil types (Oxisol and Podzol) located on the dam shores of Sugar Mill Saint Lucia-Araras/SP. The soil was sampled in the depths of 0-0.2 and 0.2-0.4m, and was determined some of its chemical attributes (nutrient content and organic matter, cationic exchange capacity - CEC, etc.), physical (particle size distribution, density and porosity) and microbiological (microbial biomass and basal respiration). Two models were built, one containing two hierarchical levels of FoMs (Mod1), and another containing three levels (Mod2), in order to try to isolate FoMs highly correlated from each other within a top-level FoM. At FoMs of Mod1 were assigned various combinations of weights, and those of Mod2 were assigned weights from three methods, distribution from fixed value, classification and pair-wise comparison. In the Mod1, in virtually all combinations of weights used, values of Soil Quality Index (SQI) were superior in older forests, while the most recent forest presented the lowest SQI, for both types of soil. The variation of SQI values obtained from the sets of weights used also differed between the combinations tested, with the set of values of the ancient forest showing smaller amplitude. It could also be observed that the sets of values of Oxisol showed higher SQI and lower amplitude in relation to that of Podzol. It was observed that these facts are due mainly to the soil organic matter content (MO), which differs between the vegetations and soil types, and influences many parameters used in the model. Thus, in the structures where MO had

  10. Artificial perches as a nucleation technique for restoration of a riparian environment: characterization of the seed rain and of natural regeneration

    OpenAIRE

    Aline Luiza Tomazi; Carlos Eduardo Zimmermann; Rudi Ricardo Laps

    2010-01-01

    Riparian habitats are important to the maintenance of ecological processes and environmental services. However, a significant portion of the riparian vegetation in the Brazilian Atlantic forest has been removed in response to increasing human pressure. Therefore, the application of restoration techniques in these habitats becomes essential. In this context, a nucleation model with 18 artificial perches was evaluated for the restoration of a degraded riparian area in Gaspar, Santa Catarina, Br...

  11. Quantifying geomorphic controls on riparian forest dynamics using a linked physical-biological model: implications for river corridor conservation

    Science.gov (United States)

    Stella, J. C.; Harper, E. B.; Fremier, A. K.; Hayden, M. K.; Battles, J. J.

    2009-12-01

    each patch. Model parameters of tree life-history traits (e.g., dispersal timing) and hydrogeomorphic processes (e.g., sedimentation rate) were determined by field and experimental studies, and aerial LIDAR, with separate range of values for point bar versus floodplain habitats. In most runs, abandoned channels were colonized one third as frequently as point bars, but supported much larger forest patches when colonization was successful (from 15-99% of forest area, depending on point bar success). Independent evaluation of aerial photos confirm that cottonwood forest stands associated with abandoned channels were less frequent (38% of all stands) but more extensive (53% of all forest area) relative to those caused by migrating point bars. Results indicate that changes to the rate and scale of river migration, and particularly channel abandonment, from human and climatic alterations to the flow regime will likely influence riparian corridor-wide tree population structure and forest dynamics, with consequences for the community of organisms that depend on this habitat.

  12. Enhanced transpiration by riparian buffer trees in response to advection in a humid temperate agricultural landscape

    Science.gov (United States)

    Hernandez-Santana, V.; Asbjornsen, H.; Sauer, T.; Isenhart, T.; Schilling, K.; Schultz, Ronald

    2011-01-01

    Riparian buffers are designed as management practices to increase infiltration and reduce surface runoff and transport of sediment and nonpoint source pollutants from crop fields to adjacent streams. Achieving these ecosystem service goals depends, in part, on their ability to remove water from the soil via transpiration. In these systems, edges between crop fields and trees of the buffer systems can create advection processes, which could influence water use by trees. We conducted a field study in a riparian buffer system established in 1994 under a humid temperate climate, located in the Corn Belt region of the Midwestern U.S. (Iowa). The goals were to estimate stand level transpiration by the riparian buffer, quantify the controls on water use by the buffer system, and determine to what extent advective energy and tree position within the buffer system influence individual tree transpiration rates. We primarily focused on the water use response (determined with the Heat Ratio Method) of one of the dominant species (Acer saccharinum) and a subdominant (Juglans nigra). A few individuals of three additional species (Quercus bicolor, Betula nigra, Platanus occidentalis) were monitored over a shorter time period to assess the generality of responses. Meteorological stations were installed along a transect across the riparian buffer to determine the microclimate conditions. The differences found among individuals were attributed to differences in species sap velocities and sapwood depths, location relative to the forest edge and prevailing winds and canopy exposure and dominance. Sapflow rates for A. saccharinum trees growing at the SE edge (prevailing winds) were 39% greater than SE interior trees and 30% and 69% greater than NW interior and edge trees, respectively. No transpiration enhancement due to edge effect was detected in the subdominant J. nigra. The results were interpreted as indicative of advection effects from the surrounding crops. Further, significant

  13. Climate and local geomorphic interactions drive patterns of riparian forest decline along a Mediterranean Basin river

    Science.gov (United States)

    Stella, John C.; Riddle, Jess; Piégay, Hervé; Gagnage, Matthieu; Trémélo, Marie-Laure

    2013-11-01

    Dynamic fluvial processes strongly influence ecological communities and ecosystem health in riverine and riparian ecosystems, particularly in drought-prone regions. In these systems, there is a need to develop tools to measure impacts from local and regional hydrogeomorphic changes on the key biological and physical processes that sustain riparian ecosystem health and potential recovery. We used dendrochronology of Populus nigra, a riparian tree that is vulnerable to changes in local hydrology, to analyze ecosystem response following channel incision due to gravel mining along the Drôme River, a Mediterranean Basin stream in southern France. We cored 55 trees at seven floodplain sites, measured ring widths, and calculated basal area growth to compare the severity and timing of local growth decline along the river. Current basal area increment (BAI) growth per tree ranged almost 10-fold among sites (7.7 ± 1.3 to 63.9 ± 15.2 cm2 year- 1, mean ± SE) and these differences were significant. Mean BAI was correlated positively with the proportion of healthy trees at a site, and negatively with proportion of dead canopy area. Regime shift analysis of the tree-ring series indicates that tree growth declined significantly at four sites since 1978, coincident with documented channel incision. In addition, patterns of low growth and crown dieback are consistent with stress due to reduced water supply. The most impaired sites were not directly adjacent to local mining pits visible on aerial photographs, nor did the sequence of growth regime shifts suggest a pattern of channel incision progressing from these areas. The initiation of site growth declines was most typically associated with drought years, and the most impaired sites were spatially distributed to suggest the influence of local bedrock controls on soil depth. Climate in the Drôme basin and in the Mediterranean region is trending significantly toward hotter growing seasons with a decrease in summer river

  14. An operational methodology for riparian land cover fine scale regional mapping for the study of landscape influence on river ecological status

    Science.gov (United States)

    Tormos, T.; Kosuth, P.; Souchon, Y.; Villeneuve, B.; Durrieu, S.; Chandesris, A.

    2010-12-01

    Preservation and restoration of river ecosystems require an improved understanding of the mechanisms through which they are influenced by landscape at multiple spatial scales and particularly at river corridor scale considering the role of riparian vegetation for regulating and protecting river ecological status and the relevance of this specific area for implementing efficient and realistic strategies. Assessing correctly this influence over large river networks involves accurate broad scale (i.e. at least regional) information on Land Cover within Riparian Areas (LCRA). As the structure of land cover along rivers is generally not accessible using moderate-scale satellite imagery, finer spatial resolution imagery and specific mapping techniques are needed. For this purpose we developed a generic multi-scale Object Based Image Analysis (OBIA) scheme able to produce LCRA maps in different geographic context by exploiting information available from very high spatial resolution imagery (satellite or airborne) and/or metric to decametric spatial thematic data on a given study zone thanks to fuzzy expert knowledge classification rules. A first experimentation was carried out on the Herault river watershed (southern of France), a 2650 square kilometers basin that presents a contrasted landscape (different ecoregions) and a total stream length of 1150 Km, using high and very high multispectral remotely-sensed images (10m Spot5 multispectral images and 0.5m aerial photography) and existing spatial thematic data. Application of the OBIA scheme produced a detailed (22 classes) LCRA map with an overall accuracy of 89% and a Kappa index of 83% according to a land cover pressures typology (six categories). A second experimentation (using the same data sources) was carried out on a larger test zone, a part of the Normandy river network (25 000 square kilometers basin; 6000 km long river network; 155 ecological stations). This second work aimed at elaborating a robust statistical

  15. Novel wildlife in the Arctic: the influence of changing riparian ecosystems and shrub habitat expansion on snowshoe hares.

    Science.gov (United States)

    Tape, Ken D; Christie, Katie; Carroll, Geoff; O'Donnell, Jonathan A

    2016-01-01

    Warming during the 20th century has changed the arctic landscape, including aspects of the hydrology, vegetation, permafrost, and glaciers, but effects on wildlife have been difficult to detect. The primary aim of this study is to examine the physical and biological processes contributing to the expanded riparian habitat and range of snowshoe hares (Lepus americanus) in northern Alaska. We explore linkages between components of the riparian ecosystem in Arctic Alaska since the 1960s, including seasonality of stream flow, air temperature, floodplain shrub habitat, and snowshoe hare distributions. Our analyses show that the peak discharge during spring snowmelt has occurred on average 3.4 days per decade earlier over the last 30 years and has contributed to a longer growing season in floodplain ecosystems. We use empirical correlations between cumulative summer warmth and riparian shrub height to reconstruct annual changes in shrub height from the 1960s to the present. The effects of longer and warmer growing seasons are estimated to have stimulated a 78% increase in the height of riparian shrubs. Earlier spring discharge and the estimated increase in riparian shrub height are consistent with observed riparian shrub expansion in the region. Our browsing measurements show that snowshoe hares require a mean riparian shrub height of at least 1.24-1.36 m, a threshold which our hindcasting indicates was met between 1964 and 1989. This generally coincides with observational evidence we present suggesting that snowshoe hares became established in 1977 or 1978. Warming and expanded shrub habitat is the most plausible reason for recent snowshoe hare establishment in Arctic Alaska. The establishment of snowshoe hares and other shrub herbivores in the Arctic in response to increasing shrub habitat is a contrasting terrestrial counterpart to the decline in marine mammals reliant on decreasing sea ice. PMID:26527375

  16. Modeling the evolution of riparian woodlands facing climate change in three European rivers with contrasting flow regimes.

    Directory of Open Access Journals (Sweden)

    Rui P Rivaes

    Full Text Available Global circulation models forecasts indicate a future temperature and rainfall pattern modification worldwide. Such phenomena will become particularly evident in Europe where climate modifications could be more severe than the average change at the global level. As such, river flow regimes are expected to change, with resultant impacts on aquatic and riparian ecosystems. Riparian woodlands are among the most endangered ecosystems on earth and provide vital services to interconnected ecosystems and human societies. However, they have not been the object of many studies designed to spatially and temporally quantify how these ecosystems will react to climate change-induced flow regimes. Our goal was to assess the effects of climate-changed flow regimes on the existing riparian vegetation of three different European flow regimes. Cases studies were selected in the light of the most common watershed alimentation modes occurring across European regions, with the objective of appraising expected alterations in the riparian elements of fluvial systems due to climate change. Riparian vegetation modeling was performed using the CASiMiR-vegetation model, which bases its computation on the fluvial disturbance of the riparian patch mosaic. Modeling results show that riparian woodlands may undergo not only at least moderate changes for all flow regimes, but also some dramatic adjustments in specific areas of particular vegetation development stages. There are circumstances in which complete annihilation is feasible. Pluvial flow regimes, like the ones in southern European rivers, are those likely to experience more pronounced changes. Furthermore, regardless of the flow regime, younger and more water-dependent individuals are expected to be the most affected by climate change.

  17. Riparian forest potential to retain sediment and carbon evaluated by the 137Cs fallout and carbon isotopic ratio techniques

    International Nuclear Information System (INIS)

    Riparian forests can provide an important service for aquatic ecosystems by sequestering hill slope-derived sediments. However, the width of a riparian buffer zone required to filter sediments is not yet well-understood. Here are used two complementary tracers to measure sediment retention. The 137Cs technique and the soil carbon isotopic ratios (δ 13C) are utilized to investigate sediment deposition and erosion rates on a slope transect cultivated with sugarcane followed by a secondary riparian forest zone in Iracemapolis, State of Sao Paulo, Brazil. The 137Cs technique and the δ 13C analysis showed that the width of a riparian vegetation in accordance to a Brazilian Environmental Law (N. 4.771/65) was not sufficient in trapping sediments coming from agricultural lands, but indicated the importance of these forests as a conservation measure at the watershed scale. The complementary δ 13C analysis together with soil morphology aspects allowed a better interpretation of the sediment redistribution along the sugarcane and riparian forest transect. (author)

  18. Riparian vegetation, Colorado River, and climate: Five decades of spatiotemporal dynamics in the Grand Canyon with river regulation

    Science.gov (United States)

    Sankey, Joel B.; Ralston, Barbara E.; Grams, Paul E.; Schmidt, John C.; Cagney, Laura E.

    2015-08-01

    Documentation of the interacting effects of river regulation and climate on riparian vegetation has typically been limited to small segments of rivers or focused on individual plant species. We examine spatiotemporal variability in riparian vegetation for the Colorado River in Grand Canyon relative to river regulation and climate, over the five decades since completion of the upstream Glen Canyon Dam in 1963. Long-term changes along this highly modified, large segment of the river provide insights for management of similar riparian ecosystems around the world. We analyze vegetation extent based on maps and imagery from eight dates between 1965 and 2009, coupled with the instantaneous hydrograph for the entire period. Analysis confirms a net increase in vegetated area since completion of the dam. Magnitude and timing of such vegetation changes are river stage-dependent. Vegetation expansion is coincident with inundation frequency changes and is unlikely to occur for time periods when inundation frequency exceeds approximately 5%. Vegetation expansion at lower zones of the riparian area is greater during the periods with lower peak and higher base flows, while vegetation at higher zones couples with precipitation patterns and decreases during drought. Short pulses of high flow, such as the controlled floods of the Colorado River in 1996, 2004, and 2008, do not keep vegetation from expanding onto bare sand habitat. Management intended to promote resilience of riparian vegetation must contend with communities that are sensitive to the interacting effects of altered flood regimes and water availability from river and precipitation.

  19. Environmental tolerance of an invasive riparian tree and its potential for continued spread in the southwestern US

    Science.gov (United States)

    Reynolds, L.V.; Cooper, D.J.

    2010-01-01

    Questions: Exotic plant invasion may be aided by facilitation and broad tolerance of environmental conditions, yet these processes are poorly understood in species-rich ecosystems such as riparian zones. In the southwestern United States (US) two plant species have invaded riparian zones: tamarisk (Tamarix ramosissima, T. chinensis, and their hybrids) and Russian olive (Elaeagnus angustifolia). We addressed the following questions: (1) is Russian olive able to tolerate drier and shadier conditions than cottonwood and tamarisk? (2) Can tamarisk and cottonwood facilitate Russian olive invasion? Location: Arid riparian zones, southwestern US. Methods: We analyzed riparian tree seedling requirements in a controlled experiment, performed empirical field studies, and analyzed stable oxygen isotopes to determine the water sources used by Russian olive. Results: Russian olive survival was significantly higher in dense shade and low moisture conditions than tamarisk and cottonwood. Field observations indicated Russian olive established where flooding cannot occur, and under dense canopies of tamarisk, cottonwood, and Russian olive. Tamarisk and native riparian plant species seedlings cannot establish in these dry, shaded habitats. Russian olive can rely on upper soil water until 15 years of age, before utilizing groundwater. Conclusions: We demonstrate that even though there is little evidence of facilitation by cottonwood and tamarisk, Russian olive is able to tolerate dense shade and low moisture conditions better than tamarisk and cottonwood. There is great potential for continued spread of Russian olive throughout the southwestern US because large areas of suitable habitat exist that are not yet inhabited by this species. ?? 2010 International Association for Vegetation Science.

  20. Parsimonious Model for Simulating Total Mercury and Methylmercury in Boreal Streams Based on Riparian Flow Paths and Seasonality.

    Science.gov (United States)

    Eklöf, Karin; Kraus, Andrea; Futter, Martyn; Schelker, Jakob; Meili, Markus; Boyer, Elizabeth W; Bishop, Kevin

    2015-07-01

    The complexity of mercury (Hg) biogeochemistry has made it difficult to model surface water concentrations of both total Hg (THg) and especially methylmercury (MeHg), the species of Hg having the highest potential for bioaccumulation. To simulate THg and MeHg variation in low-order streams, we have adapted a conceptual modeling framework where a continuum of lateral flows through riparian soils determines streamflow concentrations. The model was applied to seven forest catchments located in two boreal regions in Sweden spanning a range of climatic, soil, and forest management conditions. Discharge, and simulated riparian soil water concentrations profiles, represented by two calibrated parameters, were able to explain much of the variability of THg and MeHg concentrations in the streams issuing from the catchments (Nash Sutcliffe (NS) up to 0.54 for THg and 0.58 for MeHg). Model performance for all catchments was improved (NS up to 0.76 for THg and 0.85 for MeHg) by adding two to four parameters to represent seasonality in riparian soil water THg and MeHg concentrations profiles. These results are consistent with the hypothesis that riparian flow-pathways and seasonality in riparian soil concentrations are the major controls on temporal variation of THg and MeHg concentrations in low-order streams. PMID:25970167

  1. Nitrate and dissolved nitrous oxide in groundwater within cropped fields and riparian buffers

    Directory of Open Access Journals (Sweden)

    D.-G. Kim

    2009-01-01

    Full Text Available Transport and fate of dissolved nitrous oxide (N2O in groundwater and its significance to nitrogen dynamics within agro-ecosystems are poorly known in spite of significant potential of N2O to global warming and ozone depletion. Increasing denitrification in riparian buffers may trade a reduction in nitrate (NO3 transport to surface waters for increased N2O emissions resulting from denitrification-produced N2O dissolved in groundwater being emitted into the air when groundwater flows into a stream or a river. This study quantifies the transport and fate of NO3 and dissolved N2O moving from crop fields through riparian buffers, assesses whether groundwater exported from crop fields and riparian buffers is a significant source of dissolved N2O emissions, and evaluates the Intergovernmental Panel on Climate Change (IPCC methodology to estimate dissolved N2O emission. We measured concentrations of NO3; chloride (Cl; pH; dissolved N2O, dissolved oxygen (DO, and organic carbon (DOC in groundwater under a multi-species riparian buffer, a cool-season grass filter, and adjacent crop fields located in the Bear Creek watershed in central Iowa, USA. In both the multi-species riparian buffer and the cool-season grass filter, concentrations of dissolved N2O in the groundwater did not change as it passed through the sites, even when the concentrations of groundwater NO3 were decreased by 50% and 59%, respectively, over the same periods. The fraction of N lost to leaching and runoff (0.05 and the modified N2O emission factor, [ratio of dissolved N2O flux to N input (0.00002] determined for the cropped fields indicate that the current IPCC methodology overestimates dissolved N2O flux in the sites. A low ratio between

  2. Penetration and survival of riparian tree roots in compacted coarse gravel mixtures

    Science.gov (United States)

    Muellner, Michael; Weissteiner, Clemens; Konzel, Christoph; Rauch, Hans Peter

    2016-04-01

    Root growth and penetration of riparian trees along paved cycling paths and service roads of rivers causes often traffic safety problems. Damages occur mostly on street surfaces with thin asphalt layers and especially in the upper part of the pavement structure. The maintainers of these roads are faced with frequent and high annual repair costs in order to guarantee traffic safety and pleasant cycling conditions. Analyses of the dominating process mechanisms demonstrated that mainly the naturally growing pioneer vegetation along rivers is responsible for the asphalt damages caused by their constant and rapid growth. The investigations of the root growth characteristics showed that tree roots mostly penetrate the road structure between the gravel sublayer and the asphalt because of the high compaction of the layer itself. In a second step of the research project the influence of different gravel size mixtures on the root penetration and survival are analysed. Coarse gravel size mixtures with the lowest possible fine granular fraction are suposed to inhibit root growth due to the mechanical impedance and air pruning of roots. Furthermore coarse gravel size mixtures could influence the presence of condensate formed at the underside of the asphalt layer. Therefore seven different compositions of matrix stone gravel size mixtures (0/32, 4/32, 8/32, 16/32, 0/64, 8/64 hydraulic bound mixture and 16/64) as sublayer material were tested in a small scale experimental set-up. Wooden boxes with a dimension of 1x1.5x0.5 m and 0.5x0.5x0.5 m were used as frames for the different matrix stone mixtures. On one side the boxes were delimited to the surrounding soil with a steel mesh followed by a wire mesh and a geotextile. Boxes were located in an 80 cm deep hole on a 30 cm thick drainage layer. Willow and poplar cuttings were planted laterally to the root penetrable side of the boxes. Large boxes were filled and compacted with 6 different gravel size mixtures (all but 4/32) and

  3. Evaluation of the riparian forest state program in Pitangueiras county, Parana /
    Avaliação do programa estadual “Mata Ciliar” no município de Pitangueiras, Paraná

    OpenAIRE

    Cristovon Videira Ripol; Ricardo Ralisch; Marli Candalaft Alcantara Parra Peres

    2009-01-01

    Riparian forest restoration is fundamental for maintenance of vegetable, animal and human life. The objective of this study was to evaluate the efficiency of a Riparian Forest state program in the enlargement of the riparian forests in Pitangueiras county, state of Paraná, in the period of 2004 to 2006. Concerning the riparian reforestation, it was ansewered the reasons that convinced the farmers to join the program, the main difficulties found in its execution, and their views on environment...

  4. Using Aerial Photography to Estimate Riparian Zone Impacts in a Rapidly Developing River Corridor

    Science.gov (United States)

    Owers, Katharine A.; Albanese, Brett; Litts, Thomas

    2012-03-01

    Riparian zones are critical for protecting water quality and wildlife, but are often impacted by human activities. Ongoing threats and uncertainty about the effectiveness of buffer regulations emphasize the importance of monitoring riparian buffers through time. We developed a method to rapidly categorize buffer width and landuse attributes using 2007 leaf-on aerial photography and applied it to a 65 km section of the Toccoa River in north Georgia. We repeated our protocol using 1999 leaf-off aerial photographs to assess the utility of our approach for monitoring. Almost half (45%) of the length of the Toccoa River was bordered by buffers less than 50 ft wide in 2007, with agricultural and built-up lands having the smallest buffers. The percentage of river length in each buffer width category changed little between 1999 and 2007, but we did detect a 5% decrease in agricultural land use, a corresponding increase in built-up land use, and an additional 149 buildings within 100 ft of the river. Field verification indicated that our method overestimated buffer widths and forested land use and underestimated built-up land use and the number of buildings within 100 ft of the river. Our methodology can be used to rapidly assess the status of riparian buffers. Including supplemental data (e.g., leaf-off imagery, road layers) will allow detection of the fine-scale impacts underestimated in our study. Our results on the Toccoa River reflect historic impacts, exemptions and variances to regulations, and the ongoing threat of vacation home development. We recommend additional monitoring, improvements in policy, and efforts to increase voluntary protection and restoration of stream buffers.

  5. Total and Labile Phosphorus Concentrations as Influenced by Riparian Buffer Soil Properties.

    Science.gov (United States)

    Young, Eric O; Ross, Donald S

    2016-01-01

    Riparian buffers can act as a phosphorus (P) source under active stream bank erosion. Using soil and landscape variables (soil series, drainage class, organic matter, and pH) to index P concentrations could improve P loss risk tools for buffers. The objectives of this study were (i) to determine if soil properties could predict total and labile P concentrations within a 10-ha riparian buffer and (ii) to quantify the degree of spatial dependence of P and related properties. Soil samples were taken in 15-cm increments to a depth of 60 cm using a grid ( = 71) from an established riparian buffer along the Rock River in Vermont. Total soil P (TP), plant-available P determined by Modified Morgan extraction (MM-P), pH, soil organic matter (SOM), soil texture, and select cations were measured. We found that TP (152-1536 mg P kg) and MM-P (0.4-14.6 mg kg) ranged widely, with distinct differences between soil series. Mean TP and MM-P were greater in alluvial and glaciolacustrine soils compared with glacial till. Across all samples, MM-P was weakly related to soil properties; however, total labile P (orthophosphate + organic P measured by ICP) and unreactive labile P (ICP-P - colorimetric-P) could both be predicted by SOM ( = 0.59 and 0.73, respectively). Strong spatial dependence was found for P and related properties as revealed by geospatial analyses. Results show that P availability in the buffer was strongly related to soil genesis and support site-specific approaches for P loss risk evaluation in buffers. PMID:26828185

  6. Trophic overlap between fish and riparian spiders: potential impacts of an invasive fish on terrestrial consumers.

    Science.gov (United States)

    Jackson, Michelle C; Woodford, Darragh J; Bellingan, Terence A; Weyl, Olaf L F; Potgieter, Michael J; Rivers-Moore, Nick A; Ellender, Bruce R; Fourie, Hermina E; Chimimba, Christian T

    2016-03-01

    Studies on resource sharing and partitioning generally consider species that occur in the same habitat. However, subsidies between linked habitats, such as streams and riparian zones, create potential for competition between populations which never directly interact. Evidence suggests that the abundance of riparian consumers declines after fish invasion and a subsequent increase in resource sharing of emerging insects. However, diet overlap has not been investigated. Here, we examine the trophic niche of native fish, invasive fish, and native spiders in South Africa using stable isotope analysis. We compared spider abundance and diet at upstream fishless and downstream fish sites and quantified niche overlap with invasive and native fish. Spider abundance was consistently higher at upstream fishless sites compared with paired downstream fish sites, suggesting that the fish reduced aquatic resource availability to riparian consumers. Spiders incorporated more aquatic than terrestrial insects in their diet, with aquatic insects accounting for 45-90% of spider mass. In three of four invaded trout rivers, we found that the average proportion of aquatic resources in web-building spider diet was higher at fishless sites compared to fish sites. The probability of web-building and ground spiders overlapping into the trophic niche of invasive brown and rainbow trout was as high as 26 and 51%, respectively. In contrast, the probability of spiders overlapping into the trophic niche of native fish was always less than 5%. Our results suggest that spiders share resources with invasive fish. In contrast, spiders had a low probability of trophic overlap with native fish indicating that the traits of invaders may be important in determining their influence on ecosystem subsidies. We have added to the growing body of evidence that invaders can have cross-ecosystem impacts and demonstrated that this can be due to niche overlap. PMID:27087934

  7. Do beavers promote the invasion of non-native Tamarix in the Grand Canyon riparian zone

    Science.gov (United States)

    Mortenson, S.G.; Weisberg, P.J.; Ralston, B.E.

    2008-01-01

    Beavers (Castor canadensis Kuhl) can influence the competitive dynamics of plant species through selective foraging, collection of materials for dam creation, and alteration of hydrologic conditions. In the Grand Canyon National Park, the native Salix gooddingii C.R.Ball (Goodding's willow) and Salix exigua Nutt. (coyote willow) are a staple food of beavers. Because Salix competes with the invasive Tamarix ramosissima Ledeb., land mangers are concerned that beavers may cause an increase in Tamarix through selective foraging of Salix. A spatial analysis was conducted to assess whether the presence of beavers correlates with the relative abundance of Salix and Tamarix. These methods were designed to detect a system-wide effect of selective beaver foraging in this large study area (367 linear km of riparian habitat). Beavers, Salix, and Tamarix co-occurred at the broadest scales because they occupied similar riparian habitat, particularly geomorphic reaches of low and moderate resistivity. Once the affinity of Salix for particular reach types was accounted for, the presence of Salix was independent of beaver distribution. However, there was a weak positive association between beaver presence and Salix cover. Salix was limited to geomorphic settings with greater sinuosity and distinct terraces, while Tamarix occurred in sinuous and straighter sections of river channel (cliffs, channel margins) where it dominated the woody species composition. After accounting for covariates representing river geomorphology, the proportion of riparian surfaces covered by Tamarix was significantly greater for sites where beavers were present. This indicates that either Tamarix and beavers co-occur in similar habitats, beavers prefer habitats that have high Tamarix cover, or beavers contribute to Tamarix dominance through selective use of its native woody competitors. The hypothesis that beaver herbivory contributes to Tamarix dominance should be considered further through more

  8. Relationships Between Nitrogen Transformation Rates and Gene Abundance in a Riparian Buffer Soil

    Science.gov (United States)

    Wu, Lin; Osmond, Deanna L.; Graves, Alexandria K.; Burchell, Michael R.; Duckworth, Owen W.

    2012-11-01

    Denitrification is a critical biogeochemical process that results in the conversion of nitrate to volatile products, and thus is a major route of nitrogen loss from terrestrial environments. Riparian buffers are an important management tool that is widely utilized to protect water from non-point source pollution. However, riparian buffers vary in their nitrate removal effectiveness, and thus there is a need for mechanistic studies to explore nitrate dynamics in buffer soils. The objectives of this study were to examine the influence of specific types of soluble organic matter on nitrate loss and nitrous oxide production rates, and to elucidate the relationships between these rates and the abundances of functional genes in a riparian buffer soil. Continuous-flow soil column experiments were performed to investigate the effect of three types of soluble organic matter (citric acid, alginic acid, and Suwannee River dissolved organic carbon) on rates of nitrate loss and nitrous oxide production. We found that nitrate loss rates increased as citric acid concentrations increased; however, rates of nitrate loss were weakly affected or not affected by the addition of the other types of organic matter. In all experiments, rates of nitrous oxide production mirrored nitrate loss rates. In addition, quantitative polymerase chain reaction (qPCR) was utilized to quantify the number of genes known to encode enzymes that catalyze nitrite reduction (i.e., nirS and nirK) in soil that was collected at the conclusion of column experiments. Nitrate loss and nitrous oxide production rates trended with copy numbers of both nir and 16s rDNA genes. The results suggest that low-molecular mass organic species are more effective at promoting nitrogen transformations than large biopolymers or humic substances, and also help to link genetic potential to chemical reactivity.

  9. Analysis of carbon and nitrogen dynamics in riparian soils: model development.

    Science.gov (United States)

    Brovelli, A; Batlle-Aguilar, J; Barry, D A

    2012-07-01

    The quality of riparian soils and their ability to buffer contaminant releases to aquifers and streams are connected intimately to moisture content and nutrient dynamics, in particular of carbon (C) and nitrogen (N). A multi-compartment model-named the Riparian Soil Model (RSM)-was developed to help investigate the influence and importance of environmental parameters, climatic factors and management practices on soil ecosystem functioning in riparian areas. The model improves existing tools, in particular regarding its capability to simulate a wide range of temporal scales, from days to centuries, along with its ability to predict the concentration and vertical distribution of dissolved organic matter (DOM). It was found that DOM concentration controls the amount of soil organic matter (SOM) stored in the soil as well as the respiration rate. The moisture content was computed using a detailed water budget approach, assuming that within each time step all the water above field capacity drains to the layer underneath, until it becomes fully saturated. A mass balance approach was also used for nutrient transport, whereas the biogeochemical reaction network was developed as an extension of an existing C and N turnover model. Temperature changes across the soil profile were simulated analytically, assuming periodic temperature changes in the topsoil. To verify the consistency of model predictions and to illustrate its capabilities, a synthetic but realistic soil profile in a deciduous forest was simulated. Model parameters were taken from the literature, and model predictions were consistent with experimental observations for a similar scenario. Modelling results stressed the importance of environmental conditions on SOM cycling in soils. The mineral and organic C and N stocks fluctuate at different time scales in response to oscillations in climatic conditions and vegetation inputs/uptake. PMID:22578521

  10. Water uptake in woody riparian phreatophytes of the southwestern United States: a stable isotope study

    International Nuclear Information System (INIS)

    Alluvial forest associations are often dominated by woody phreatophytes, plants that are tightly linked to aquifers for water uptake. Anthropogenic hydrological alterations (e.g., water impoundment or diversion) are of clear importance to riparian ecosystem function. Because decreased frequency of flooding and depression of water tables may, in effect, sever riparian plants from their natural water sources, research was undertaken to determine water uptake patterns for the dominant native and introduced woody taxa of riparian plant communities of the southwestern United States. At floodplain study sites along the Bill Williams and lower Colorado Rivers (Arizona, USA), naturally occurring D and 18O were used to distinguish among potential water sources. Isotopic ratios from potential uptake locations were compared to water extracted from the dominant woody taxa of the study area (Populus fremontii, Salix gooddingii, and Tamarix ramosissima) to elucidate patterns of water absorption. Isotopic composition of water obtained from sapwood cores did not differ significantly from heartwood or branch water, suggesting that heartwood water exchange, stem capacitance, and phloem sap mixing may be inconsequential in actively transpiring Salix and Populus. There was evidence for close hydrologic linkage of river, ground, and soil water during the early part of the growing season. Surface soils exhibited D enrichment due to cumulative exposure to evaporation as the growing season progressed. Isotopic ratios of water extracted from Populus and Salix did not exhibit isotopic enrichment and were not significantly different from groundwater or saturated soil water sources, indicating a phreatophytic uptake pattern. Associations of isotopic ratios with water relations parameters indicated high levels of canopy evaporation and possible use of moisture from unsaturated alluvial soils in addition to groundwater in Tamarix. (author)

  11. Riparian zones attenuate nitrogen loss following bark beetle-induced lodgepole pine mortality

    Science.gov (United States)

    Biederman, Joel A.; Meixner, Thomas; Harpold, Adrian A.; Reed, David E.; Gutmann, Ethan D.; Gaun, Janelle A.; Brooks, Paul D.

    2016-03-01

    A North American bark beetle infestation has killed billions of trees, increasing soil nitrogen and raising concern for N loss impacts on downstream ecosystems and water resources. There is surprisingly little evidence of stream N response in large basins, which may result from surviving vegetation uptake, gaseous loss, or dilution by streamflow from unimpacted stands. Observations are lacking along hydrologic flow paths connecting soils with streams, challenging our ability to determine where and how attenuation occurs. Here we quantified biogeochemical concentrations and fluxes at a lodgepole pine-dominated site where bark beetle infestation killed 50-60% of trees. We used nested observations along hydrologic flow paths connecting hillslope soils to streams of up to third order. We found soil water NO3 concentrations increased 100-fold compared to prior research at this and nearby southeast Wyoming sites. Nitrogen was lost below the major rooting zone to hillslope groundwater, where dissolved organic nitrogen (DON) increased by 3-10 times (mean 1.65 mg L-1) and NO3-N increased more than 100-fold (3.68 mg L-1) compared to preinfestation concentrations. Most of this N was removed as hillslope groundwater drained through riparian soils, and NO3 remained low in streams. DON entering the stream decreased 50% within 5 km downstream, to concentrations typical of unimpacted subalpine streams (~0.3 mg L-1). Although beetle outbreak caused hillslope N losses similar to other disturbances, up to 5.5 kg ha-1y-1, riparian and in-stream removal limited headwater catchment export to <1 kg ha-1y-1. These observations suggest riparian removal was the dominant mechanism preventing hillslope N loss from impacting streams.

  12. Seeing the landscape for the trees: Metrics to guide riparian shade management in river catchments

    Science.gov (United States)

    Johnson, Matthew F.; Wilby, Robert L.

    2015-05-01

    Rising water temperature (Tw) due to anthropogenic climate change may have serious consequences for river ecosystems. Conservation and/or expansion of riparian shade could counter warming and buy time for ecosystems to adapt. However, sensitivity of river reaches to direct solar radiation is highly heterogeneous in space and time, so benefits of shading are also expected to be site specific. We use a network of high-resolution temperature measurements from two upland rivers in the UK, in conjunction with topographic shade modeling, to assess the relative significance of landscape and riparian shade to the thermal behavior of river reaches. Trees occupy 7% of the study catchments (comparable with the UK national average) yet shade covers 52% of the area and is concentrated along river corridors. Riparian shade is most beneficial for managing Tw at distances 5-20 km downstream from the source of the rivers where discharge is modest, flow is dominated by near-surface hydrological pathways, there is a wide floodplain with little landscape shade, and where cumulative solar exposure times are sufficient to affect Tw. For the rivers studied, we find that approximately 0.5 km of complete shade is necessary to off-set Tw by 1°C during July (the month with peak Tw) at a headwater site; whereas 1.1 km of shade is required 25 km downstream. Further research is needed to assess the integrated effect of future changes in air temperature, sunshine duration, direct solar radiation, and downward diffuse radiation on Tw to help tree planting schemes achieve intended outcomes.

  13. Influence of monsoon-related riparian phenology on yellow-billed cuckoo habitat selection in Arizona

    Science.gov (United States)

    Wallace, Cynthia S.A.; Villarreal, Miguel; Van Riper, Charles, III

    2013-01-01

    Aim: The western yellow-billed cuckoo (Coccyzus americanus occidentalis), a Neotropical migrant bird, is facing steep population declines in its western breeding grounds owing primarily to loss of native habitat. The favoured esting habitat for the cuckoo in the south-western United States is low-elevation riparian forests and woodlands. Our aim was to explore relationships between vegetation phenology patterns captured by satellite phenometrics and the distribution of the yellow-billed cuckoo, and to use this information to map cuckoo habitat. Location: Arizona, USA. Methods: Land surface phenometrics were derived from satellite Advanced Very High-Resolution Radiometer (AVHRR), bi-weekly time-composite, ormalized difference vegetation index (NDVI) data for 1998 and 1999 at a resolution of 1 km. Fourier harmonics were used to analyse the waveform of the annual NDVI profile in each pixel. To create the models, we coupled 1998 satellite phenometrics with 1998 field survey data of cuckoo presence or absence and with point data that sampled riparian and cottonwood–willow vegetation types. Our models were verified and refined using field and satellite data collected in 1999. Results: The models reveal that cuckoos prefer areas that experience peak greenness 29 days later, are 36% more dynamic and slightly (< 1%) more productive than their average cottonwood–willow habitat. The results support a scenario in which cuckoos migrate northwards, following the greening of riparian corridors and surrounding landscapes in response to monsoon precipitation, but then select a nesting site based on optimizing the near-term foraging potential of the neighbourhood. Main conclusions: The identification of preferred phenotypes within recognized habitat can be used to refine future habitat models, inform habitat response to climate change, and suggest adaptation strategies. For example, models of phenotype preferences can guide management actions by identifying and prioritizing for

  14. Functional redundancy as a tool for bioassessment: A test using riparian vegetation.

    Science.gov (United States)

    Bruno, D; Gutiérrez-Cánovas, C; Velasco, J; Sánchez-Fernández, D

    2016-10-01

    There is an urgent need to track how natural systems are responding to global change in order to better guide management efforts. Traditionally, taxonomically based metrics have been used as indicators of ecosystem integrity and conservation status. However, functional approaches offer promising advantages that can improve bioassessment performance. In this study, we aim to test the applicability of functional redundancy (FR), a functional feature related to the stability, resistance and resilience of ecosystems, as a tool for bioassessment, looking at woody riparian communities in particular. We used linear mixed-effect models to investigate the response of FR and other traditional biomonitoring indices to natural (drought duration) and anthropogenic stress gradients (flow regulation and agriculture) in a Mediterranean basin. Such indices include species richness, a taxonomic index, and the Riparian Quality Index, which is an index of ecological status. Then, we explored the ability of FR and the other indices to discriminate between different intensities of human alteration. FR showed higher explanatory capacity in response to multiple stressors, although we found significant negative relationships between all the biological indices (taxonomic, functional and ecological quality) and stress gradients. In addition, FR was the most accurate index to discriminate among different categories of human alteration in both perennial and intermittent river reaches, which allowed us to set threshold values to identify undisturbed (reference condition), moderately disturbed and highly disturbed reaches in the two types of river. Using these thresholds and the best-fitting model, we generated a map of human impact on the functional redundancy of riparian communities for all the stretches of the river network. Our results demonstrate that FR presents clear advantages over traditional methods, which suggests that it should be part of the biomonitoring toolbox used for

  15. INDICATED SPECIES TO RESTORATION OF RIPARIAN FORESTS IN SUBWATERSHED OF PEIXE-BOI RIVER, PARÁ STATE

    OpenAIRE

    Igor do Vale; Luiz Gonzaga Silva Costa; Izildinha Souza Miranda

    2014-01-01

    http://dx.doi.org/10.5902/1980509815736This study aims to indicate native species to be used in the restoration of degraded riparian forests in the subwatershed of Peixe-Boi river. All trees and shrubs with diameter at breast height (DBH) > 5 cm were inventoried in ten areas of secondary forest and six areas of igapó forest. The results were analyzed by Principal Component Analysis and the silviculture of the species was assessed by literature review. In Igapó areas 66 species were found; ...

  16. Nitrogen transformations and greenhouse gas emissions from a riparian wetland soil: An undisturbed soil column study

    International Nuclear Information System (INIS)

    Riparian wetlands bordering intensively managed agricultural fields can act as biological filters that retain and transform agrochemicals such as nitrate and pesticides. Nitrate removal in wetlands has usually been attributed to denitrification processes which in turn imply the production of greenhouse gases (CO2 and N2O). Denitrification processes were studied in the Salburua wetland (northern Spain) by using undisturbed soil columns which were subsequently divided into three sections corresponding to A-, Bg- and B2g-soil horizons. Soil horizons were subjected to leaching with a 200 mg NO3- L-1 solution (rate: 90 mL day-1) for 125 days at two different temperatures (10 and 20 oC), using a new experimental design for leaching assays which enabled not only to evaluate leachate composition but also to measure gas emissions during the leaching process. Column leachate samples were analyzed for NO3- concentration, NH4+ concentration, and dissolved organic carbon. Emissions of greenhouse gases (CO2 and N2O) were determined in the undisturbed soil columns. The A horizon at 20 oC showed the highest rates of NO3- removal (1.56 mg N-NO3- kg-1 DW soil day-1) and CO2 and N2O production (5.89 mg CO2 kg-1 DW soil day-1 and 55.71 μg N-N2O kg-1 DW soil day-1). For the Salburua wetland riparian soil, we estimated a potential nitrate removal capacity of 1012 kg N-NO3- ha-1 year-1, and potential greenhouse gas emissions of 5620 kg CO2 ha-1 year-1 and 240 kg N-N2O ha-1 year-1. - Research Highlights: →A new experimental design is proposed for leaching assays to simulate nitrogen transformations in riparian wetland soil. →Denitrification is the main process responsible for nitrate removal in the riparian zone of Salburua wetland. →In Salburua, considerable amounts of greenhouse gases (N2O and CO2) are emitted to the atmosphere during denitrification.

  17. Vascular Flora of a Riparian Site on the Canadian River, Cleveland County, Oklahoma

    OpenAIRE

    Lacy Burgess; Bruce W. Hoagland

    2006-01-01

    This article reports the results of an inventory of the vascular plants from a riparian site in central Oklahoma. One hundred and sixty-three species of vascular plants in 131 genera and 45 families were collected. The most species were collected from the families Asteraceae (32) and Poaceae (26). Fifty-eight species were annuals, 97 perennials, and 8 biennials. Eight species of woody plants were present. Twenty-nine species, or 18% of the flora, were exotic to Oklahoma. No species listed as ...

  18. Perspectives on screening winter-flood-tolerant woody species in the riparian protection forests of the three gorges reservoir.

    Directory of Open Access Journals (Sweden)

    Fan Yang

    Full Text Available The establishment of riparian protection forests in the Three Gorges Reservoir (TGR is an ideal measure to cope with the eco-environmental problems of the water-level fluctuation zone (WLFZ. Thus, the information for screening winter-flood-tolerant woody plant species is useful for the recovery and re-establishment of the riparian protection forests in the TGR WLFZ. Therefore, we discussed the possibilities of constructing and popularizing riparian protection forests in the TGR WLFZ from several aspects, including the woody plant species distribution in the WLFZ, the survival rate analyses of suitable candidate woody species under controlled flooding conditions, the survival rate investigation of some woody plant species planted in the TGR WLFZ, and the physiological responses of some woody plant species during the recovery stage after winter floods. The results of woody species investigation showed that most woody plant species that existed as annual seedlings in the TGR WLFZ are not suitable candidates for the riparian protection forests. However, arbor species (e.g., Salix matsudana, Populus×canadensis, Morus alba, Pterocarya stenoptera, Taxodium ascendens, and Metasequoia glyptostroboides and shrub species (e.g., Salix variegata, Distylium chinensis, Lycium chinense, Myricaria laxiflora, and Rosa multiflora might be considered suitable candidates for the riparian protection forests in the TGR WLFZ by survival rate analyses under controlled winter flooding conditions, and survival rate investigations of woody plant species planted in the TGR WLFZ, respectively. Physiological analyses showed that P.×canadensis, M. alba, L. chinense, and S. variegata could develop specific self-repairing mechanisms to stimulate biomass accumulation and carbohydrate synthesis via the increases in chlorophyll pigments and photosynthesis during recovery after winter floods. Our results suggested these woody plant species could endure the winter flooding stress

  19. Spatial and temporal distribution of acetochlor in sediments and riparian soils of the Songhua River Basin in northeastern China

    Institute of Scientific and Technical Information of China (English)

    Xiaoyin Sun; Qixing Zhou; Wenjie Ren; Xuhui Li; Liping Ren

    2011-01-01

    The Songhua River Basin is a burgeoning agricultural area in the modern times in China.Particularly in recent years,increasing chemical fertilizers and pesticides have been applied with the development of agricultural production.However,the situation of nonpoint source pollution (NSP) from agricultural production in this basin is still obscure.In order to solve the problem,the occurrence and distribution of acetochlor in sediments and riparian soils of the Songhua River Basin before rain season and after rain season were investigated.In addition,total organic carbon was analyzed.The result showed that the concentration of acetochlor ranged from 0.47 to 11.76 μg/kg in sediments and 0.03 to 709.37 μg/kg in riparian soils.During the high flow period in 2009,the mean concentration was 4.79 μg/kg in sediments and 0.75 μg/kg in riparian soils,respectively.Similarly,the mean concentration was 2.53 μg/kg in sediments and 61,36 μg/kg in riparian soils,during the average flow period in 2010.There was a significant correlation between the concentration of acetochlor and total organic carbon in surface sediments.Moreover,the distribution of acetochlor in sediments of the Songhua River was signiicantly correlated to land use and topography of the watershed.The investigated data suggested that the concentration of acetochlor in the Songnen Plain and the Sanjiang Plain was higher than that in the other areas of the basin,and riparian buffering zones in these areas had been destroyed by human activities.The optimal agricultural measures to alleviate the contamination of pesticides should be adopted,including controlling agricultural application of acetochlor and ecological restoration of riparian buffering strips.

  20. Novel plant communities limit the effects of a managed flood to restore riparian forests along a large regulated river

    Science.gov (United States)

    Cooper, D.J.; Andersen, D.C.

    2012-01-01

    Dam releases used to create downstream flows that mimic historic floods in timing, peak magnitude and recession rate are touted as key tools for restoring riparian vegetation on large regulated rivers. We analysed a flood on the 5th-order Green River below Flaming Gorge Dam, Colorado, in a broad alluvial valley where Fremont cottonwood riparian forests have senesced and little recruitment has occurred since dam completion in 1962. The stable post dam flow regime triggered the development of novel riparian communities with dense herbaceous plant cover. We monitored cottonwood recruitment on landforms inundated by a managed flood equal in magnitude and timing to the average pre-dam flood. To understand the potential for using managed floods as a riparian restoration tool, we implemented a controlled and replicated experiment to test the effects of artificially modified ground layer vegetation on cottonwood seedling establishment. Treatments to remove herbaceous vegetation and create bare ground included herbicide application (H), ploughing (P), and herbicide plus ploughing (H+P). Treatment improved seedling establishment. Initial seedling densities on treated areas were as much as 1200% higher than on neighbouring control (C) areas, but varied over three orders of magnitude among the five locations where manipulations were replicated. Only two replicates showed the expected seedling density rank of (H+P)>P>H>C. Few seedlings established in control plots and none survived 1 year. Seedling density was strongly affected by seed rain density. Herbivory affected growth and survivorship of recruits, and few survived nine growing seasons. Our results suggest that the novel plant communities are ecologically and geomorphically resistant to change. Managed flooding alone, using flows equal to the pre-dam mean annual peak flood, is an ineffective riparian restoration tool where such ecosystem states are present and floods cannot create new habitat for seedling establishment

  1. Responses of butachlor degradation and microbial properties in a riparian soil to the cultivation of three different plants

    Institute of Scientific and Technical Information of China (English)

    Changming Yang; Mengmeng Wang; Haiyan Chen; Jianhua Li

    2011-01-01

    A pot experiment was conducted to investigate the biodegradation dynamics and related microbial ecophysiological responses to butachlor addition in a riparian soil planted with different plants such as Phragmites australis,Zizaaia aquatica,and Acorus calamus.The results showed that there were significant differences in microbial degradation dynamics of butachlor in the rhizosphere soils among the three riparian plants.A.calamus displays a significantly higher degradation efficiency of butachlor in the rhizosphere soils,as compared with Z aquatica and P.australis.Half-life time of butachlor degradation in the rhizospheric soils of P.australis,Z.aquatica,and A.calamus were 7.5,9.8 and 5.4 days,respectively.Residual butachlor concentration in A.calamus rhizosphere soil was 35.2% and 21.7% lower than that in Z.aquatica and P.australis rhizosphere soils,respectively,indicating that A.calamus showed a greater improvement effect on biodegradation of butachlor in rhizosphere soils than the other two riparian plant.In general,microbial biomass and biochemical activities in rhizosphere soils were depressed by butachlor addition,despite the riparian plant types.However,rhizospheric soil microbial ecophysiological responses to butachlor addition significantly (P < 0.05) differed between riparian plant species.Compared to Z.aquatica and P.australis,A.calamus showed significantly larger microbial number,higher enzyme activities and soil respiration rates in the rhizosphere soils.The results indicated that A.calamus have a better alleviative effect on inhibition of microbial growth due to butachlor addition and can be used as a suitable riparian plant for detoxifying and remediating butaehlor contamination from agricultural nonpoint pollution.

  2. Influence of long-term trends of flooding on habitat conditions in lowland riparian wetlands under low antropopression

    Science.gov (United States)

    Mirosław-Świątek, Dorota; Grygoruk, Mateusz

    2016-04-01

    Temporal, volumetric and areal trends of flooding remain dominant factors shaping habitat conditions of riparian wetlands. In contemporary Europe, where the pristine extent of riparian wetlands strongly decreased due to antropopression and the flow regime of majority of rivers was decently modified in agricultural and hydropower purposes, valuable riparian habitats that remained in good ecological state require appropriate maintenance of floods. Even though multiple environmental regulations were implemented worldwide in order to mitigate negative effects of antropopression to flow regime and habitats, it is the climatic change that challenges riparian ecosystem management to the extent comparable (if not higher) than the direct human interventions. Wishing to detect probable influence of the ongoing climatic change on the flood regime one should search for catchment systems of a low antropopression, where the long term variability of flood extents, flood depths and recurrence intervals are likely to reflect climatic changes rather than human activity. In our study we analysed 60-years long time series of the discharge data of Biebrza river (NE Poland) that was found in numerous studies a reference in a temperate-continental European riparian and mire ecosystem research. Daily data of river discharge was used as boundary conditions in the WETFLOD - a developed integrated river-floodplain-groundwater flow model applied to the environment of Lower Biebrza Basin. The model was used to simulate and analyze trends of changes in flood extent and water depths in selected, well preserved vegetation patches namely the Caricetum appropinquatae, Caricetum gracilis, Phragmitetum communis and Glycerietum maximae. Temporal trends were analysed on the basis of distribution deciles of flood extents, depths and recurrence intervals. Study revealed that flood extents and flood depths in the first decade of the 21st century were decently different from the ones modeled for the second

  3. Asteretum lanceolati: Xenospontaneous community on wet and riparian habitats

    Directory of Open Access Journals (Sweden)

    Obratov-Petković Dragica

    2011-01-01

    Full Text Available Invasive species Aster lanceolatus grows on moist habitats on the whole territory of Serbia. In Belgrade, this species is recorded with a higher degree of presence at a number of localities. With the aim to investigate the community in which this species is dominant, the wide area of Serbia was researched, and 8 localities on the territory of Belgrade were chosen for the analysis of the community. Floristic structure of the community was determined by the standard Braun-Blanquet method (1964, phytogeographical analysis was performed according to Gajić (1980, 1984, and determination of life forms according to Raunkier (Ellenberg, Mueller-Dombois, 1967. pH soil analysis and electric conductivity (EC were performed at all investigated localities. It was established that the community dominates the moist habitats of Belgrade. It is composed of 104 species and among them Aster lanceolatus Willd., Cichorium intybus L., Agropyrum repens (L. Beauv., Calystegia sepium (L. R. Br., Cirsium arvense (L. Scop., Symphytum officinale L. and Rumex obtusifolius L. are the most frequent. In relation to life forms, the community has hemicriptophytes character, and in relation to phytogeography Euroasian and Middle Europaean floral elements are dominant, with a high presence of cosmopolitan and adventive floral elements. On the locialities Veliko Ratno ostrvo (island and Makiš, EC values point to the fact that the amount of nutrient in the soil is higher than at other localities.

  4. PHYTOSOCIOLOGICAL AND PHYTOGEOGRAPHIC CHARACTERIZATION OF A RIPARIAN FOREST SECTOR IN ALFREDO WAGNER, SANTA CATARINA STATE, AS SUBSIDY FOR ECOLOGICAL RESTORATION

    Directory of Open Access Journals (Sweden)

    Ana Carolina da Silva

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812342The understanding of floristic and structure of tree communities is essential to subside the strategies offorest restoration. In this sense, a phyto-sociological survey was conducted in a forest fragment situated along a tributary of Caeté river, in Alfredo Wagner, state of Santa Catarina, in order to: i know the structureof trees and flora in this forest, ii classify the species found according to ecological groups and iii comparethe flora of the study area with other studies in Araucaria forest (FOM, Atlantic Rain Forest (FOD andthe transition area between FOM-FOD of Santa Catarina state. In this fragment, 10 plots of 400 m2 wereallocated, where all individual trees with the circumference at breast height (CBH, measured at 1.30 mabove the ground greater than or equal to 15.7 cm were measured, marked and identified. The species wereclassified into the following succession groups: pioneer, climax light-demanding or climax shade-tolerant.The Rectified Correspondence Analysis (DCA was used for the floristic comparison. The structure of thetree component was described by the density, frequency, dominance and importance value (VI. The resultsshowed elevated species richness (98 species. It was found typical species of FOM, such as Araucariaangustifolia (Bert. Kuntze, and species characteristics of FOD such as Byrsonima ligustrifolia A.Juss.,confirming the study fragment as an area of ecological tension between FOM and FOD. The species withmost elevated VI were Psychotria vellosiana Benth., Alsophila setosa Kaulf. and Guatteria australis A.St.-Hil. The species with elevated VI, for their considerable representation in the area, are important in therestoration of degraded riparian forests in the region. The species seedlings plantation should be plannedobserving the group successional of each species, planting pioneer and light-demanding climax speciesfirst (e.g. Psychotria vellosiana, followed by, after the

  5. Florística e estrutura da comunidade arbórea de um remanescente florestal ripário no município de Guariba, Estado de São Paulo, Brasil. Floristic and structure of the arboreal community of riparian forest remain at Guariba municipality, São Paulo State, Brazil.

    Directory of Open Access Journals (Sweden)

    Nicole Maria Marson DONADIO

    2009-06-01

    Full Text Available O conhecimento sobre a composição eestrutura de comunidades florestais é fundamentalpara embasar ações de conservação e restauração.O objetivo deste trabalho foi realizar olevantamento florístico e descrever a estrutura dacomunidade arbórea de um remanescente florestallocalizado no município de Guariba, Estado de SãoPaulo. Foram alocadas 30 parcelas de 10 x 10 m,para amostrar os indivíduos arbóreos e arbustivoscom diâmetro à altura do peito (DAP ³ 5 cm.Foram encontradas 54 espécies, pertencentes a 47gêneros, distribuídos em 32 famílias botânicas,com índice de diversidade (H’ de 2,67 eequabilidade (J de 0,20. As famílias Meliaceae eFabaceae apresentaram maior riqueza em espécies.Calophyllum brasiliensis, Astronium graveolens,Scheffera morototoni, Xylopia aromatica eProtium widgrenii destacaram-se como as espéciesde maior valor de importância. Foram amostrados420 indivíduos. A presença de espécies do cerradosugere condição de ecótono e a dominância de umaespécie higrófila indica saturação hídrica em parteda área. A distribuição dos indivíduos em classesde tamanho revelou uma comunidade emregeneração com a maioria dos indivíduos com até15,0 cm de DAP e distribuídos entre 7 e 14,9 m,e com estoques de jovens tanto das espéciespioneiras como secundárias podendo garantir ofuturo da comunidade. Em termos sucessionais aárea estudada encontra-se em estádio de médiopara avançado.Knowledge of the composition andstructure of arboreal communities is paramount forconservation and restoration efforts. The mainobjectives of this study were to characterize thearboreal species floristic composition and describethe structure of the arboreal community of aremaining forest located at the municipality ofGuariba, State of São Paulo. Thirty plots of 10 x 10 mwere allocated. In each plot, diameter and heightwere measured for each individual tree withdiameter at breast height (dbh ³ 5 cm. Fifty-fourspecies were

  6. Partitioning and availability of uranium and nickel in contaminated riparian sediments.

    Science.gov (United States)

    Sowder, Andrew G; Bertsch, Paul M; Morris, Pamela J

    2003-01-01

    The effects of iron oxides and organic matter on the partitioning and chemical lability of U and Ni were examined for contaminated riparian sediments from the U.S. Department of Energy's Savannah River Site. In sequential extractions of four sediments that ranged from 12.7 to 82.2 g kg(-1) in organic carbon, U was found almost exclusively in moderately labile fractions (93% in acid-soluble + organically bound). Nickel was distributed across all operationally defined fractions, including substantial amounts in the very labile fractions (4-15% in water-soluble + exchangeable), noncrystalline and crystalline iron oxides (38-49%), and in the nonlabile residual fraction (25-34%). Aqueous U concentrations in 1:1 sediment-water extracts were highly correlated to dissolved organic carbon (DOC) (R2 = 0.96; p organic carbon. Discrete mineral phases were also identified as nonlabile reservoirs of anthropogenic metals. In spite of comparably high sediment concentrations, Ni appears to be significantly more available than U in riparian sediments and therefore warrants greater consideration in terms of environmental consequences (i.e., transport, biological uptake, and toxicity). PMID:12809289

  7. Influences of increased riparian thaw depths on stream temperatures and chemical export in beaded arctic streams

    Science.gov (United States)

    Neilson, B. T.; Merck, M. F.; Kling, G. W.; Cory, R. M.; Harrold, K. H.; King, T. V.; Overbeck, L. D.; Page, S. E.; Miller, B. L.; Kane, D. L.

    2013-12-01

    Beaded streams are prominent on the North Slope of Alaska and thus influence the processing and export of constituents. These streams consist of small pools connected by shallow chutes, are typically first order, and exhibit variability in the magnitude of water storage and residence times throughout the open water season. This study examines the changes in pool temperatures in Imnavait Creek for the purpose of understanding heat and mass transport through the system to investigate potential impacts of climate variations. We found that the dominant heat sources and sinks that influence pool thermal stratification, including feedbacks due to absorption of solar radiation by dissolved organic matter (DOM), are key to understanding the evolution of water chemistry and material export. Exchanges between the riparian and hillslope areas with the streams also influenced the timing of solute export and water chemistry through subsurface lateral inputs. Under relatively low flow conditions, we found that pool stratification was persistent, chemical differences between pool surface and bottom waters were strong, and riparian influences on pool bottom water chemistry can be substantial. Temperature modeling indicated that the dominant heat sources vary between stratified layers and that increases in thaw depths surrounding these pools can influence stratification, mixing, residence times, and the fate of stream constituents such as carbon and nutrients.

  8. Hydrogeomorphic controls on hyporheic and riparian transport in two headwater mountain streams during base flow recession

    Science.gov (United States)

    Ward, Adam S.; Schmadel, Noah M.; Wondzell, Steven M.; Harman, Ciaran; Gooseff, Michael N.; Singha, Kamini

    2016-02-01

    Solute transport along riparian and hyporheic flow paths is broadly expected to respond to dynamic hydrologic forcing by streams, aquifers, and hillslopes. However, direct observation of these dynamic responses is lacking, as is the relative control of geologic setting as a control on responses to dynamic hydrologic forcing. We conducted a series of four stream solute tracer injections through base flow recession in each of two watersheds with contrasting valley morphology in the H.J. Andrews Experimental Forest, monitoring tracer concentrations in the stream and in a network of shallow riparian wells in each watershed. We found hyporheic mean arrival time, temporal variance, and fraction of stream water in the bedrock-constrained valley bottom and near large roughness elements in the wider valley bottom were not variable with discharge, suggesting minimal control by hydrologic forcing. Conversely, we observed increases in mean arrival time and temporal variance and decreasing fraction stream water with decreasing discharge near the hillslopes in the wider valley bottom. This may indicate changes in stream discharge and valley bottom hydrology control transport in less constrained locations. We detail five hydrogeomorphic responses to base flow recession to explain observed spatial and temporal patterns in the interactions between streams and their valley bottoms. Models able to account for the transition from geologically dominated processes in the near-stream subsurface to hydrologically dominated processes near the hillslope will be required to predict solute transport and fate in valley bottoms of headwater mountain streams.

  9. Valorization of Damages to Riparian Forests; Valoracion de danos en la vegetacion de ribera

    Energy Technology Data Exchange (ETDEWEB)

    Prieto Rodriguez, A.; Varela Nieto, J. M.; Magdaleno Mas, F.; Diaz Balteiro, L.; Saiz de Omenaca Gonzalez, J. A.; Saiz de Omenaca Gonzalez, J.; Lazaro Benito, F.; Macias Palomo, A.

    2008-07-01

    The economic values of the autochthonous riparian forests are well recognized today, thanks to their multiples functions and benefits. Nevertheless, no economic analysis were fulfilled up to date, that include the whole diversity of these benefits, due to the lack of monitoring and evaluation of their environmental services, and the difficulties to valorize them. In order to contribute to the protection of their ecological status, through the sustainable management of their diverse components, a procedure for the whole valorization of the damages and impacts on the environmental, social and productive functions of the riparian forests of continental spain is presented. This procedure must be the basis for the establishment of the sanctions and indemnifications associated to accidents, negligence or bad intentioned acts on their components, independently of their type of property (public or private). Thus, it is necessary to consider their functions, but also the physical environments where the vegetations lives, their legal contexts, the potential impacts and the methodologies for their valorization. (Author)

  10. ASSESSMENT OF A 5-YEAR-OLD REHABILITATED RIPARIAN FOREST: IS IT ALREADY SUSTAINABLE?

    Directory of Open Access Journals (Sweden)

    Vinícius Londe

    2015-08-01

    Full Text Available ABSTRACTAs important as the establishment of projects of ecological restoration is its assessment post-implementation to know whether the area is becoming self-sustainable or need to be redirected. In this way, this study aimed to know the current situation of a 5-year-old rehabilitated riparian forest,inserted in an anthropogenic impacted region,at the das Velhas River, Minas Gerais State, studying the canopy openness and recruitment of seedlings as plant indicators. 15 plots were allocated in the forest, where hemispherical photographs were taken to analyze the canopy openness and evaluate all seedlings from 0.30 m to 1.30 m height.Canopy openness ranged from 23.7% to 38.8% between seasons and only 192 seedlings were found,from 13 species, five of them exotic and aggressive. Although canopy openness was low, it seems that lateral penetration of light has been favoring the development and dominancy of plants from invasive species, whereas few native ones have been recruited. The exotic/invasive plants may compromise the success of restoration mainly by competition with native planted species. The outcomes evidenced an unsustainability of the riparian forest and the requirement of some management actions to control exotic and invasive plants and ensure the preservation of the area and its ecological roles over time.

  11. Bottom-up factors influencing riparian willow recovery in Yellowstone National Park

    Science.gov (United States)

    Tercek, M.T.; Stottlemyer, R.; Renkin, R.

    2010-01-01

    After the elimination of wolves (Canis lupis L.) in the 1920s, woody riparian plant communities on the northern range of Yellowstone National Park (YNP) declined an estimated 50%. After the reintroduction of wolves in 19951996, riparian willows (Salix spp.) on YNP's northern range showed significant growth for the first time since the 1920s. However, the pace of willow recovery has not been uniform. Some communities have exceeded 400 cm, while others are still at pre-1995 levels of 250 cm max. height) willow sites where willows had escaped elk (Cervus elaphus L.) browsing with "short" willow sites that could still be browsed. Unlike studies that manipulated willow height with fences and artificial dams, we examined sites that had natural growth differences in height since the reintroduction of wolves. Tall willow sites had greater water availability, more-rapid net soil nitrogen mineralization, greater snow depth, lower soil respiration rates, and cooler summer soil temperatures than nearby short willow sites. Most of these differences were measured both in herbaceous areas adjacent to the willow patches and in the willow patches themselves, suggesting that they were not effects of varying willow height recovery but were instead preexisting site differences that may have contributed to increased plant productivity. Our results agree with earlier studies in experimental plots which suggest that the varying pace of willow recovery has been influenced by abiotic limiting factors that interact with top-down reductions in willow browsing by elk. ?? 2010 Western North American Naturalist.

  12. Low thermal tolerances of stream amphibians in the Pacific Northwest: Implications for riparian and forest management

    Science.gov (United States)

    Bury, R.B.

    2008-01-01

    Temperature has a profound effect on survival and ecology of amphibians. In the Pacific Northwest, timber harvest is known to increase peak stream temperatures to 24??C or higher, which has potential to negatively impact cold-water stream amphibians. I determined the Critical Thermal Maxima (CT max) for two salamanders that are endemic to the Pacific Northwest. Rhyacotriton variegatus larvae acclimated at 10??C had mean CTmax of 26.7 ?? 0.7 SD??C and adults acclimated at 11??C had mean CT max of 27.9 ?? 1.1??C. These were among the lowest known values for any amphibian. Values were significantly higher for larval Dicamptodon tenebrosus acclimated at 14??C (x = 29.1 ?? 0.2??C). Although the smallest R. variegatus had some of the lowest values, size of larvae and adults did not influence CTmax in this species. Current forest practices retain riparian buffers along larger fish-bearing streams; however, such buffers along smaller headwaters and non-fish bearing streams may provide favorable habitat conditions for coldwater-associated species in the Pacific Northwest. The current study lends further evidence to the need for protection of Northwest stream amphibians from environmental perturbations. Forest guidelines that include riparian buffer zones and configurations of upland stands should be developed, while monitoring amphibian responses to determine their success. ?? 2008 Brill Academic Publishers.

  13. Heavy metal distribution of natural and reclaimed tidal riparian wetlands in south estuary, China

    Institute of Scientific and Technical Information of China (English)

    Honggang Zhang; Baoshan Cui; Kejiang Zhang

    2011-01-01

    We evaluated the distribution and accumulation ofCd,Cr,Cu,Ni,Pb and Zn in two plant species (Scirpus tripueter Linn.and Cyperus malaccensis Lam.),in water and soils sampled from the reclaimed tidal riparian wetlands (RTRWs) and the natural riparian wetlands (NRWs) in the Pearl River Estuary (PRE).The results showed that the concentrations of studied heavy metals in soils exceeded the eco-toxic threshold recommended by US EPA.The concentrations ofCd,Cr and Zn in plants may lead to toxic effects.The heavy metal concentrations were high in water and low in soils of RTRWs compared with that in the NRWs.The accumulation of heavy metals in the roots of plants was higher in NRWs than those in RTRWs while the opposite result was found for heavy metal accumulation in shoots.Based on the bioaccumulation and translocation factors,the plants in NRWs had a higher capacity to accumulate heavy metals while higher abilities to transport heavy metals from roots to shoots were observed in RTRWs.Heavy metal contaminations in RTRWs were dominated by anthropogenic sources from both side uplands and river water,whereas in NRWs,the metal accumulations were simultaneously affected by anthropogenic and natural factors

  14. Health Assessment of Mercury Exposure in a Riparian Community in the Madeira River

    Directory of Open Access Journals (Sweden)

    Vega C. M.

    2014-07-01

    Full Text Available Mercury concentrations were analyzed in a riparian community from the Cuniã Lake RESEX (a riparian extrativist reserve at the Madeira river, located in the Amazon region. The studied population age ranged from 2 to 90 years old and hair was used as biomarker. A total of 252 hair samples were collected from fishermen families. Hg concentrations averaged 6.0 (IC95% 5.58-6.58 ± 3.9 μg.g-1 (SD. The fish consumption for adults in this community ranges from 40 to 600 grams per day. The results showed significant gender differences for Hg levels (p-value < 0.05; for male individuals the average was 7.4 (IC 95% 5.56-8.28±4,5 μg.g-1 and for female individuals was of 5.0 (IC 95% 4.49-5.54 ±3.3 μg.g-1. Studies on neurological symptoms and diet of this community are under way along with other clinical trials and biochemical measurements.

  15. Comparison of water consumption in two riparian vegetation communities along the central Platte River, Nebraska, 2008–09 and 2011

    Science.gov (United States)

    Hall, Brent M.; Rus, David L.

    2013-01-01

    The Platte River is a vital natural resource for the people, plants, and animals of Nebraska. A recent study quantified water use by riparian woodlands along central reaches of the Platte River, Nebraska, finding that water use was mainly regulated below maximum predicted levels. A comparative study was launched through a cooperative partnership between the U.S. Geological Survey, the Central Platte Natural Resources District, the Nebraska Department of Natural Resources, and the Nebraska Environmental Trust to compare water use of a riparian woodland with that of a grazed riparian grassland along the central Platte River. This report describes the results of the 3-year study by the U.S. Geological Survey to measure the evapotranspiration (ET) rates in the two riparian vegetation communities. Evapotranspiration was measured during 2008–09 and 2011 using the eddy-covariance method at a riparian woodland near Odessa, hereinafter referred to as the “woodland site,” and a riparian grassland pasture near Elm Creek, hereinafter referred to as the “grassland site.” Overall, annual ET totals at the grassland site were 90 percent of the annual ET measured at the woodland site, with averages of 653 millimeters (mm) and 726 mm, respectively. Evapotranspiration rates were similar at the grassland site and the woodland site during the spring and fall seasons, but at the woodland site ET rates were higher than those of the grassland site during the peak-growth summer months of June through August. These seasonal differences and the slightly lower ET rates at the grassland site were likely the result of differing plant communities, disturbance effects related to grazing and flooding, and climatic differences between the sites. The annual water balance was calculated for each site and indicated that the predominant factors in the water balance at both sites were ET and precipitation. Annual precipitation for the study period ranged from near to above the normal

  16. Experimental studies of aluminum mobility in organic rich riparian soil and stream water in Sweden

    Science.gov (United States)

    Wonisch, H.; Cory, N.; Buffam, I.; Laudon, H.; Bishop, K.; Dietzel, M.; Köhler, S. J.

    2009-04-01

    The role of organic acids in mobilizing and controlling aluminum (Al) from a riparian soil profile into a small humic-rich stream draining a forested catchment area was studied in Northern Sweden. Three in-situ soil and stream water manipulation experiments were performed by changing total concentrations of Al and silica while keeping pH constant between 4.8 and 5.6 to decipher the processes regulating stream Al solubility and export. Removal of added silica could not be observed along the 80 m stream reach during the stream manipulation despite a saturation index for Proto-Imogolite higher than 2.5. Removal of dissolved Al and DOC in the stream and the superficial soil solutions of the unsaturated zone occurred at molar Al/DOC ratios above 0.13±0.01. For the lower soil horizons that are in permanent contact with groundwater (45-65 cm) and supply the stream with water during the largest part of the year a ratio above 0.073±0.01 was sufficient to induce Al removal. In all experiments (lab and field) an apparent ion activity product (IAP) for Al(OH)3 of 10.5±0.5 was necessary to induce Al removal. This IAP is rarely reached in the soil solutions or the adjacent stream despite large temporal fluctuations of both TOC and pH during the last 10 years. Al/TOC ratios in both environments are independent of pH and have a constant Al/TOC ratio with minimal variation; 0.013±0.002 (n=61) for the stream and 0.037±0.010 (n=135) for the riparian soil waters within the catchment. The similarities in the riparian soil depth profiles for BaCl2 exchangeable Al and TOC concentrations indicate that the soil organic exchanger complex may explain the small variability of the Al/TOC ratio in the soil. The loss of Al from the soil water during the transport through the riparian zone into the stream might be controlled by organic matter and not an inorganic Al bearing phase. However, to decipher the exact mechanism for the fixation of more than 70% of the soil solution Al in the

  17. Guild structure of a riparian avifauna relative to seasonal cattle grazing

    Science.gov (United States)

    Knopf, F.L.; Sedgwick, J.A.; Cannon, R. W.

    1988-01-01

    Knopf et al. found that summer cattle grazing has an adverse effect on the presence of certain willow-dependent songbirds. Pastures that have historical summer grazing no longer have the Willow flycatcher, Lincoln's sparrow and the White-crowned sparrow present. Yet in these same areas, birds like the American Robin, Brown-headed cowbird and the Red-winged blackbird have increased in density. One possible answer for the decrease in some songbirds is the fact that the main focus of the Arapaho National Wildlife Refuge is on waterfowl habitat, which requires large amounts of open space (opposite of desirable songbird habitat).

  18. Invasiveness does not predict impact: response of native land snail communities to plant invasions in riparian habitats.

    Directory of Open Access Journals (Sweden)

    Jitka Horáčková

    Full Text Available Studies of plant invasions rarely address impacts on molluscs. By comparing pairs of invaded and corresponding uninvaded plots in 96 sites in floodplain forests, we examined effects of four invasive alien plants (Impatiens glandulifera, Fallopia japonica, F. sachalinensis, and F.× bohemica in the Czech Republic on communities of land snails. The richness and abundance of living land snail species were recorded separately for all species, rare species listed on the national Red List, and small species with shell size below 5 mm. The significant impacts ranged from 16-48% reduction in snail species numbers, and 29-90% reduction in abundance. Small species were especially prone to reduction in species richness by all four invasive plant taxa. Rare snails were also negatively impacted by all plant invaders, both in terms of species richness or abundance. Overall, the impacts on snails were invader-specific, differing among plant taxa. The strong effect of I. glandulifera could be related to the post-invasion decrease in abundance of tall nitrophilous native plant species that are a nutrient-rich food source for snails in riparian habitats. Fallopia sachalinensis had the strongest negative impact of the three knotweeds, which reflects differences in their canopy structure, microhabitat humidity and litter decomposition. The ranking of Fallopia taxa according to the strength of impacts on snail communities differs from ranking by their invasiveness, known from previous studies. This indicates that invasiveness does not simply translate to impacts of invasion and needs to be borne in mind by conservation and management authorities.

  19. Invasiveness does not predict impact: response of native land snail communities to plant invasions in riparian habitats.

    Science.gov (United States)

    Horáčková, Jitka; Juřičková, Lucie; Šizling, Arnošt L; Jarošík, Vojtěch; Pyšek, Petr

    2014-01-01

    Studies of plant invasions rarely address impacts on molluscs. By comparing pairs of invaded and corresponding uninvaded plots in 96 sites in floodplain forests, we examined effects of four invasive alien plants (Impatiens glandulifera, Fallopia japonica, F. sachalinensis, and F.× bohemica) in the Czech Republic on communities of land snails. The richness and abundance of living land snail species were recorded separately for all species, rare species listed on the national Red List, and small species with shell size below 5 mm. The significant impacts ranged from 16-48% reduction in snail species numbers, and 29-90% reduction in abundance. Small species were especially prone to reduction in species richness by all four invasive plant taxa. Rare snails were also negatively impacted by all plant invaders, both in terms of species richness or abundance. Overall, the impacts on snails were invader-specific, differing among plant taxa. The strong effect of I. glandulifera could be related to the post-invasion decrease in abundance of tall nitrophilous native plant species that are a nutrient-rich food source for snails in riparian habitats. Fallopia sachalinensis had the strongest negative impact of the three knotweeds, which reflects differences in their canopy structure, microhabitat humidity and litter decomposition. The ranking of Fallopia taxa according to the strength of impacts on snail communities differs from ranking by their invasiveness, known from previous studies. This indicates that invasiveness does not simply translate to impacts of invasion and needs to be borne in mind by conservation and management authorities. PMID:25238059

  20. Restoration of riparian vegetation: A global review of implementation and evaluation approaches in the international, peer-reviewed literature.

    Science.gov (United States)

    González, Eduardo; Sher, Anna A; Tabacchi, Eric; Masip, Adrià; Poulin, Monique

    2015-08-01

    We examined how restoration of riparian vegetation has been implemented and evaluated in the scientific literature during the past 25 years. A total of 169 papers were read systematically to extract information about the following: 1) restoration strategies applied, 2) scale of monitoring and use of reference sites, 3) metrics used for evaluation, and 4) drivers of success. Hydro-geomorphic approaches (e.g., dam operations, controlled floods, landform reconfiguration) were the most frequent, followed by active plant introduction, exotic species control, natural floodplain conversion and grazing and herbivory control. Our review revealed noteworthy limitations in the spatio-temporal approaches chosen for evaluation. Evaluations were mostly from one single project and frequently ignored the multi-dimensional nature of rivers: landscape spatial patterns were rarely assessed, and most projects were assessed locally (i.e., ≤meander scale). Monitoring rarely lasted for more than six years and the projects evaluated were usually not more than six years old. The impact of the restoration was most often (43%) assessed by tracking change over time rather than by comparing restored sites to unrestored and reference sites (12%), and few projects (30%) did both. Among the ways which restoration success was evaluated, vegetation structure (e.g., abundance, density, etc.) was assessed more often (152 papers) than vegetation processes (e.g., biomass accumulation, survival, etc.) (112 papers) and vegetation diversity (78 papers). Success was attributed to hydro-geomorphic factors in 63% of the projects. Future evaluations would benefit from incorporating emerging concepts in ecology such as functional traits to assess recovery of functionality, more rigorous experimental designs, enhanced comparisons among projects, longer term monitoring and reporting failure. PMID:25974311

  1. 78 FR 16705 - Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/Fish Screen Facility Protection...

    Science.gov (United States)

    2013-03-18

    ... methods, including public notices in local newspapers and a notice in the Federal Register (77 FR 26569... Fish and Wildlife Service Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/ Fish Screen... (PCGID-PID) Pumping Plan/Fish Screen Facility Protection Project is now available. The final...

  2. 78 FR 76317 - Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/Fish Screen Facility Protection...

    Science.gov (United States)

    2013-12-17

    ... Register (77 FR 26569, May 4, 2012). We held a public meeting to solicit comments on the Draft EIS/EIR on... Fish and Wildlife Service Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/ Fish Screen...-PID) Pumping Plan/Fish Screen Facility Protection Project is now available. The ROD includes...

  3. 77 FR 26569 - Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/Fish Screen Facility Protection...

    Science.gov (United States)

    2012-05-04

    ... Fish and Wildlife Service Llano Seco Riparian Sanctuary Unit Restoration and Pumping Plant/ Fish Screen... Unit Restoration and Pumping Plant/Fish Screen Facility Protection Project in Glenn and Butte Counties... and Provident Irrigation Districts (PCGID-PID) pumping plant and fish screen facility. The draft...

  4. Effects of river ice on bank morphology and riparian vegetation along Peace River, Clayhurst to Fort Vermilion

    International Nuclear Information System (INIS)

    The effects of river ice and related flooding on the bank morphology and riparian vegetation along 655 km of the Peace River from Clayhurst, British Columbia to Fort Vermilion, Alberta were studied. The river has been regulated for hydroelectric power generation since 1968 and has experienced changes in the hydrologic and ice regimes. The rate of channel adjustments under the new hydrologic regime vary longitudinally, and depend greatly on the succession of riparian vegetation. This study was conducted to determine how much of the variation in both channel adjustment and rate of riparian succession is a result of allogenic effects of ice jams. The direct physical effects of ice and the indirect effects of ice jam flooding on the channel margin were investigated. Long term ice jam severity was found to generally peak well downstream of the principal observation point. The morphology of the channel at the severe ice jam locations fit the classical ice jam criteria of confined tight meanders with several mid-channel islands and shoals. Vegetation damage was the most visible impact to the riparian environment along the Peace River. 27 refs., 1 tab., 8 figs

  5. Dynamic evaluation of ecosystem service value of the riparian zone based on remote sensing from 1986 to 2012

    Science.gov (United States)

    Fu, B. L.; Li, Y.; Zhang, B.; Yin, B. S.; Zhu, H. L.; Xing, Z. F.

    2015-08-01

    In this paper, we calculated comparable and dynamic ecosystem service value per unit area in the riparian zone of Second Songhua River; then we also estimated changes in the value of ecosystem services resulting from land use changes; finally, we continuously evaluated the riparian ecosystem service value based on 520 basic evaluation units (BEUs) and explored the trend of the riparian ecosystem service value from 1986 to 2012. The results indicated that comparable economic values of per unit area food production of farmland ecosystems in 2012 almost increased three times more than that in 1986 from 154.83 to 382.45 ha-1; the people's willingness to pay for farmland ecosystem services increased from 0.24 in 1986 to 0.48 in 2012; the land areas supporting the environment and society generally declined, whereas areas of farmland significantly increased from 1986 to 2012; the riparian total ecosystem service value increased from 42.30 million in 1986 to 119.67 million in 2012, with an average increase rate of 4.06 % yr-1; the ecosystem service value of four reaches all have seen a sharp increase from 1986 to 2012; the average ecosystem service value of a reach was the smallest one in the four reaches, and the value of c and d reach was significantly more than other two reaches.

  6. Riparian cottonwood ecosystems and regulated flows in Kootenai and Yakima sub-basins : Volume II Yakima (overview, report, appendices); TOPICAL

    International Nuclear Information System (INIS)

    Riparian vegetation and especially cottonwood and willow plant communities are dependent on normative flows and especially, spring freshette, to provide conditions for recruitment. These plant communities therefore share much in common with a range of fish species that require natural flow conditions to stimulate reproduction. We applied tools and techniques developed in other areas to assess riparian vegetation in two very different sub-basins within the Columbia Basin. Our objectives were to: Document the historic impact of human activity on alluvial floodplain areas in both sub-basins; Provide an analysis of the impacts of flow regulation on riparian vegetation in two systems with very different flow regulation systems; Demonstrate that altered spring flows will, in fact, result in recruitment to cottonwood stands, given other land uses impacts on each river and the limitations imposed by other flow requirements; and Assess the applicability of remote sensing tools for documenting the distribution and health of cottonwood stands and riparian vegetation that can be used in other sub-basins

  7. LITTER DECOMPOSITION IN A SIERRA NEVADA RIPARIAN MEADOW AS A FUNCTION OF PLANT SPECIES, DISTANCE FROM STREAM EDGE, AND GRAZING

    Science.gov (United States)

    A key process in nutrient cycling is decomposition of plant litter and the potential resulting increase in soil nutrient levels. We compare the decomposition rate (k-value yr-1) of four riparian graminoids as influenced by plant species, distance from stream edge (2.5, 20, and 50 m), and grazi...

  8. Changes in soil organic matter compositrion after introduction of riparian vegetation on shores of hydroelectric reservoires (Southeast of Brazil)

    NARCIS (Netherlands)

    Alcantara, de F.A.; Buurman, P.; Curi, N.; Furtini Neto, A.E.; Lagen, van B.; Meijer, E.M.

    2004-01-01

    This work is part of a research program with the general objective of evaluating soil sustainability in areas surrounding hydroelectric reservoirs, which have been planted with riparian forest. The specific aims were: (i) to assess if and how the soil organic matter (SOM) chemical composition has ch

  9. Experimental and numerical study of the relation between flow paths and fate of a pesticide in a riparian wetland

    DEFF Research Database (Denmark)

    Kidmose, Jacob Baarstrøm; Dahl, Mette; Engesgaard, Peter Knudegaard;

    2010-01-01

    A field-scale pulse-injection experiment with the herbicide Isoproturon was conducted in a Danish riparian wetland. A non-reactive tracer (bromide) experiment was also carried out to characterize the physical transport system. Groundwater flow and reactive transport modelling was used to simulate...

  10. SWAT-REMM Linked Approach for Estimating Water Quality Benefits of Riparian Forest Buffers in the Little River Watershed

    Science.gov (United States)

    Riparian forest buffers (RFBs) have considerable potential for improving water quality by filtering pollutants as they are transported from upland areas to streams. Insight into the benefits of the RFBs can be gained through appropriate computer simulation of the process. The Soil and Water Assessm...

  11. Riparian Cottonwood Ecosystems and Regulated Flows in Kootenai and Yakima Sub-Basins : Volume III (Overview and Tools).

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, Bob; Braatne, Jeffrey H.

    2001-10-01

    Riparian vegetation and especially cottonwood and willow plant communities are dependent on normative flows and especially, spring freshette, to provide conditions for recruitment. These plant communities therefore share much in common with a range of fish species that require natural flow conditions to stimulate reproduction. We applied tools and techniques developed in other areas to assess riparian vegetation in two very different sub-basins within the Columbia Basin. Our objectives were to: Document the historic impact of human activity on alluvial floodplain areas in both sub-basins; Provide an analysis of the impacts of flow regulation on riparian vegetation in two systems with very different flow regulation systems; Demonstrate that altered spring flows will, in fact, result in recruitment to cottonwood stands, given other land uses impacts on each river and the limitations imposed by other flow requirements; and Assess the applicability of remote sensing tools for documenting the distribution and health of cottonwood stands and riparian vegetation that can be used in other sub-basins.

  12. An eco-hydrological approach to predicting regional vegetation and groundwater response to ecological water convergence in dryland riparian ecosystems

    Science.gov (United States)

    To improve the management strategy of riparian restoration, better understanding of the dynamic of eco-hydrological system and its feedback between hydrological and ecological components are needed. The fully distributed eco-hydrological model coupled with a hydrology component was developed based o...

  13. SHRUBBY TREE COMPONENT OF RIPARIAN CORRIDORS IN RESTORATION AND NATURAL REMAINING AREAS OF MATRIX FORESTRY, RIO NEGRINHO, SC STATE

    Directory of Open Access Journals (Sweden)

    Eliziane Carla Scariot

    2014-06-01

    Full Text Available http://dx.doi.org/10.5902/1980509814578The aim of this study was to analyze the shrubby tree component in riparian corridors in restoration process and natural remainders in a matrix forestry. We identified the richness, diversity, dispersal and pollination syndromes of the individuals and estimate the floristic similarity. The study was conducted at the producing farm of Pinus spp. wood Santa Alice, located in Rio Negrinho city, Santa Catarina state, Brazil. We adopted the center-quarter method for survey the shrubby tree component in four sample groups: CA (advanced stage of riparian corridors vegetation, CR (riparian corridors in restoration, MA (advanced stage of natural remaining, MI (intermediate stage of natural remaining. We found the highest richness and diversity index in MA and CR. Regarding the number of individuals, the dispersal and pollination syndromes predominant in all sample groups were zoochory and zoophilia. CR and CA had the highest percentage of floristic similarity while MA and MI did not form clusters. The sample group CR has composition, richness and diversity more similar to CA. This indicates that the restoration of riparian zones has conditions to rescue the components and the interactions of an ecological community.

  14. Elevated CO2 does not offset greater water stress predicted under climate change for native and exotic riparian plants

    Science.gov (United States)

    Perry, Laura G.; Shafroth, Patrick B.; Blumenthal, Dana M.; Morgan, Jack A.; LeCain, Daniel R.

    2013-01-01

    * In semiarid western North American riparian ecosystems, increased drought and lower streamflows under climate change may reduce plant growth and recruitment, and favor drought-tolerant exotic species over mesic native species. We tested whether elevated atmospheric CO2 might ameliorate these effects by improving plant water-use efficiency. * We examined the effects of CO2 and water availability on seedlings of two native (Populus deltoides spp. monilifera, Salix exigua) and three exotic (Elaeagnus angustifolia, Tamarix spp., Ulmus pumila) western North American riparian species in a CO2-controlled glasshouse, using 1-m-deep pots with different water-table decline rates. * Low water availability reduced seedling biomass by 70–97%, and hindered the native species more than the exotics. Elevated CO2 increased biomass by 15%, with similar effects on natives and exotics. Elevated CO2 increased intrinsic water-use efficiency (Δ13Cleaf), but did not increase biomass more in drier treatments than wetter treatments. * The moderate positive effects of elevated CO2 on riparian seedlings are unlikely to counteract the large negative effects of increased aridity projected under climate change. Our results suggest that increased aridity will reduce riparian seedling growth despite elevated CO2, and will reduce growth more for native Salix and Populus than for drought-tolerant exotic species.

  15. Hydrologic and Hydraulic effects of Riparian Root Networks on Streambank Stability: Is Mechanical Root-Reinforcement the Whole Story?

    Science.gov (United States)

    Riparian vegetation has a number of effects on the mechanisms by which streambanks fail, some positive and some negative. Previous research has shown that the effect of mechanical root-reinforcement on soil stability can be considerable, and can be successfully quantified and included in streambank ...

  16. Moving window analysis and riparian boundary delineation on the Northern Plains of Kruger National Park, South Africa

    Science.gov (United States)

    Kröger, Robert; Khomo, Lesego M.; Levick, Shaun; Rogers, Kevin H.

    2009-09-01

    Landscapes commonly comprise of mosaics, patches and boundaries. Riparian boundaries are complex to delineate and characterize, with a multitude of variables available for delineation. Multiple methods exist for boundary delineation such as two-dimensional wombling, constrained classification techniques and discontinuity detection. One method that has proven to be reliable in boundary delineation with one-dimensional transect data is the moving split window (MSW) analysis. This study demonstrates the efficacy of MSW to delineate grass species turnover and environmental boundaries across two geologically dissimilar riparian zones in the Kruger National Park, South Africa. There are few studies that have delineated riparian boundaries of Kruger National Park, and none that have used the MSW analysis. MSW detects significant changes in dissimilarity indices of variables along gradients. Significant shifts in dissimilarity designate boundaries at various spatial scales dictated by window sizes. Significant boundaries emerge by altering window sizes, increasing quadrat width and removing infrequent herbaceous species. By utilizing these three methods, MSW background variance was reduced and riparian and wetland/upland boundaries were sharper and more easily defined.

  17. Water and Vapor Transfer in Vadose Zone of Gobi Desert and Riparian in the Hyper Arid Environment of Ejina, China

    Science.gov (United States)

    Du, C.; Yu, J.; Wang, P.

    2014-12-01

    To reveal how water and vapor transfer in vadose zone affect evapotranspiration in Gobi desert and riparian in hyper arid region is important for understanding eco-hydrological process. Field studies and numerical simulations were imported to evaluate the water and vapor movement processes under non isothermal and lower water content conditions. The soil profiles (12 layers) in Gobi desert and riparian sites of Ejina were installed with sensors to monitor soil moisture and temperature for 1 year. The meteorological conditions and water table were measured by micro weather stations and mini-Divers respectively in the two sites. Soil properties, including particles composition, moisture, bulk density, water retention curve, and saturated hydraulic conductivity of two site soil profiles, was measured. The observations showed that soil temperatures for the two sites displayed large diurnal and seasonal fluctuations. Temperature gradients with depth resulted in a downward in summer and upward in winter and became driving force for thermal vapor movement. Soil moistures in Gobi desert site were very low and varied slowly with time. While the soil moistures in riparian site were complicated due to root distribution but water potentials remained uniform with time. The hydrus-1D was employed to simulate evapotranspiration processes. The simulation results showed the significant difference of evaporation rate in the Gobi desert and riparian sites.

  18. Riparian Cottonwood Ecosystems and Regulated Flows in Kootenai and Yakima Sub-Basins : Volume II Yakima (Overview, Report, Appendices).

    Energy Technology Data Exchange (ETDEWEB)

    Jamieson, Bob; Braatne, Jeffrey H.

    2001-10-01

    Riparian vegetation and especially cottonwood and willow plant communities are dependent on normative flows and especially, spring freshette, to provide conditions for recruitment. These plant communities therefore share much in common with a range of fish species that require natural flow conditions to stimulate reproduction. We applied tools and techniques developed in other areas to assess riparian vegetation in two very different sub-basins within the Columbia Basin. Our objectives were to: Document the historic impact of human activity on alluvial floodplain areas in both sub-basins; Provide an analysis of the impacts of flow regulation on riparian vegetation in two systems with very different flow regulation systems; Demonstrate that altered spring flows will, in fact, result in recruitment to cottonwood stands, given other land uses impacts on each river and the limitations imposed by other flow requirements; and Assess the applicability of remote sensing tools for documenting the distribution and health of cottonwood stands and riparian vegetation that can be used in other sub-basins.

  19. Dissolved organic carbon in headwater streams and riparian soil organic carbon along an altitudinal gradient in the Wuyi Mountains, China.

    Directory of Open Access Journals (Sweden)

    Wei Huang

    Full Text Available Stream water dissolved organic carbon (DOC correlates positively with soil organic carbon (SOC in many biomes. Does this relationship hold in a small geographic region when variations of temperature, precipitation and vegetation are driven by a significant altitudinal gradient? We examined the spatial connectivity between concentrations of DOC in headwater stream and contents of riparian SOC and water-soluble soil organic carbon (WSOC, riparian soil C:N ratio, and temperature in four vegetation types along an altitudinal gradient in the Wuyi Mountains, China. Our analyses showed that annual mean concentrations of headwater stream DOC were lower in alpine meadow (AM than in subtropical evergreen broadleaf forest (EBF, coniferous forest (CF, and subalpine dwarf forest (SDF. Headwater stream DOC concentrations were negatively correlated with riparian SOC as well as WSOC contents, and were unrelated to riparian soil C:N ratio. Our findings suggest that DOC concentrations in headwater streams are affected by different factors at regional and local scales. The dilution effect of higher precipitation and adsorption of soil DOC to higher soil clay plus silt content at higher elevation may play an important role in causing lower DOC concentrations in AM stream of the Wuyi Mountains. Our results suggest that upscaling and downscaling of the drivers of DOC export from forested watersheds when exploring the response of carbon flux to climatic change or other drivers must done with caution.

  20. Coupled hydrological, ecological, decision and economic models for monetary valuation of riparian ecosystem services

    Science.gov (United States)

    Goodrich, D. C.; Brookshire, D.; Broadbent, C.; Dixon, M. D.; Brand, L. A.; Thacher, J.; Benedict, K. K.; Lansey, K. E.; Stromberg, J. C.; Stewart, S.; McIntosh, M.

    2011-12-01

    Water is a critical component for sustaining both natural and human systems. Yet the value of water for sustaining ecosystem services is not well quantified in monetary terms. Ideally decisions involving water resource management would include an apples-to-apples comparison of the costs and benefits in dollars of both market and non-market goods and services - human and ecosystem. To quantify the value of non-market ecosystem services, scientifically defensible relationships must be developed that link the effect of a decision (e.g. human growth) to the change in ecosystem attributes from current conditions. It is this linkage that requires the "poly-disciplinary" coupling of knowledge and models from the behavioral, physical, and ecological sciences. In our experience another key component of making this successful linkage is development of a strong poly-disciplinary scientific team that can readily communicate complex disciplinary knowledge to non-specialists outside their own discipline. The time to build such a team that communicates well and has a strong sense of trust should not be underestimated. The research described in the presentation incorporated hydrologic, vegetation, avian, economic, and decision models into an integrated framework to determine the value of changes in ecological systems that result from changes in human water use. We developed a hydro-bio-economic framework for the San Pedro River Region in Arizona that considers groundwater, stream flow, and riparian vegetation, as well as abundance, diversity, and distribution of birds. In addition, we developed a similar framework for the Middle Rio Grande of New Mexico. There are six research components for this project: (1) decision support and scenario specification, (2) regional groundwater model, (3) the riparian vegetation model, (4) the avian model, (5) methods for displaying the information gradients in the valuation survey instruments (Choice Modeling and Contingent Valuation), and (6

  1. Analysis of carbon and nitrogen turnover in riparian soils undergoing restoration

    Science.gov (United States)

    Barry, D. A.; Batlle-Aguilar, J.; Brovelli, A.; Luster, J.; Shrestha, J.; Niklaus, P.

    2010-12-01

    The extensive change in land use from forest to agriculture and the application of large amounts of fertilizers that occurred in the last century resulted in local losses of biological diversity, and increased leaching of nutrients towards groundwater and surface water bodies. More generally, degradation of riparian zones has diminished their capacity to provide critical ecological functions, such as the ability to control and buffer nutrient cycles. In recent years, however, the key environmental importance of natural, healthy ecosystems has been progressively recognized and restoration of degraded lands towards their former natural state has become an area of active research worldwide. Land use changes and restoration practices are known to affect both soil nutrient dynamics and their transport to neighbouring areas. Microbiological transformations of the soil organic matter, including decomposition and nutrient turnover, are controlled to a large extent by soil water content, which is in turn influenced by climatic and environmental conditions such as precipitation and evapo-transpiration. The work presented here is part of the RECORD project, a large collaborative research effort undertaken to monitor and understand the changes in ecosystem functioning in riparian areas undergoing restoration. In this context a novel numerical model to simulate carbon and nitrogen transport and turnover in a one-dimensional variably saturated soil profile was developed. The model extends the capabilities of the mechanistic batch model of Porporato et al. (Adv. Water Res., 26: 45-58, 2003) to simulate (i) the transport of the soluble components towards deeper horizons and (ii) the vertical evolution of the profile and the subsequent distribution of the organic matter. The soil is divided into four compartments, each representing a different functional unit and having different physical, chemical and biological properties. Moisture dynamics is simulated using a water budget

  2. Climate and flow variation revealed in tree rings of riparian cottonwood, western North Dakota, USA

    Science.gov (United States)

    Friedman, J. M.; Edmondson, J. R.; Meko, D. M.; Touchan, R.; Griffin, E. R.; Zhou, H.

    2014-12-01

    In the western Great Plains, where old upland trees are scarce, rings of riparian trees provide an important opportunity for reconstructing past river flow and climate. We present data from 489 plains cottonwood (Populus deltoides ssp. monilifera) trees along the Little Missouri River in western North Dakota. The trees are in randomly selected flood-plain locations within the North and South units of Theodore Roosevelt National Park. The two sites are separated by 160 river km. The Little Missouri watershed contains foothills but no mountains, and most annual high flows result from snowmelt in March or April. Cores were collected and processed using standard dendrochronological methods. The effect of tree age was removed from the chronology using a single relation for the site as a whole (age-curve standardization), which preserves century-scale variation. Trees were as old as 371 years. Given that cottonwood establishment depends upon channel migration, abundant establishment from 1864-1891 at both sites suggests that one or more large floods occurred prior to this period. At the North Unit, establishment continued at a lower rate during the next century, but upstream at the South Unit, tree establishment was greatly curtailed after the 1800s. Comparison of General Land Office Maps from 1907 to recent satellite imagery confirms that channel migration in the last century was much greater within the North Unit, a difference caused in part by a downstream increase in flood amplification by ice jamming. Ring widths show that even on the flood plain riparian trees were chronically drought stressed. At both sites growth was strongly positively correlated with flow and precipitation and weakly negatively correlated with temperature. Growth was most strongly correlated with flow and precipitation in April-July, which is consistent with dendrometer-band measurements showing growth cessation in August. Whereas cottonwood establishment decreased in the 1900s, ring widths

  3. Boreal forest riparian zones regulate stream sulfate and dissolved organic carbon.

    Science.gov (United States)

    Ledesma, José L J; Futter, Martyn N; Laudon, Hjalmar; Evans, Christopher D; Köhler, Stephan J

    2016-08-01

    In boreal forest catchments, solute transfer to streams is controlled by hydrological and biogeochemical processes occurring in the riparian zone (RZ). However, RZs are spatially heterogeneous and information about solute chemistry is typically limited. This is problematic when making inferences about stream chemistry. Hypothetically, the strength of links between riparian and stream chemistry is time-scale dependent. Using a ten-year (2003-2012) dataset from a northern Swedish catchment, we evaluated the suitability of RZ data to infer stream dynamics at different time scales. We focus on the role of the RZ versus upslope soils in controlling sulfate (SO4(2)(-)) and dissolved organic carbon (DOC). A priori, declines in acid deposition and redox-mediated SO4(2)(-) pulses control sulfur (S) fluxes and pool dynamics, which in turn affect dissolved organic carbon (DOC). We found that the catchment is currently a net source of S, presumably due to release of the S pool accumulated during the acidification period. In both, RZ and stream, SO4(2-) concentrations are declining over time, whereas DOC is increasing. No temporal trends in SO4(2-) and DOC were observed in upslope mineral soils. SO4(2-) explained the variation of DOC in stream and RZ, but not in upslope mineral soil. Moreover, as SO4(2-) decreased with time, temporal variability of DOC increased. These observations indicate that: (1) SO4(2-) is still an important driver of DOC trends in boreal catchments and (2) RZ processes control stream SO4(2-) and subsequently DOC independently of upslope soils. These phenomena are likely occurring in many regions recovering from acidification. Because water flows through a heterogeneous mosaic of RZs before entering the stream, upscaling information from limited RZ data to the catchment level is problematic at short-time scales. However, for long-term trends and annual dynamics, the same data can provide reasonable representations of riparian processes and support

  4. Interactions Between Riparian Evapotranspiration and Streambed Infiltration As Expressed in Shallow Alluvial Aquifer Levels

    Science.gov (United States)

    Cadol, D. D.; Wine, M.

    2014-12-01

    Rivers in semiarid regions are typically 'ribbons of green' through otherwise sparsely vegetated landscapes. As these rivers convey water from sometimes distant sources they lose water to shallow riparian aquifers which frequently support a rich phreatophytic vegetation community. In order to monitor the interactions between streamflow, alluvial aquifers, and riparian vegetation, water levels in 3 monitoring wells near the Rio Grande at Escondida, NM, were recorded beginning in May 2013. Two summers of data reveal a strong diel signal in the water table levels, indicating a clear interaction between vegetation transpiration and aquifer storage. Likewise, comparison with stage data from a USGS gage 25 m upstream of the well transect shows a clear aquifer recharge signal. Prior work at this site during fall 2005 has suggested that streambed infiltration rates vary in a daily cycle, possibly due to temperature controls on water viscosity. In order to evaluate the relative roles of the two potential cycles we also monitored near-bed hydraulic gradients and remotely sensed vegetation indices (VIs). To measure hydraulic gradient we installed an additional piezometer in the bed of the river, screened 3 feet below the sediment surface, and began logging head in December 2013. The Enhanced Vegetation Index (EVI) was calculated from Landsat scenes that had clear views of the nearby riparian forest during the monitoring period. Preliminary results indicate that periods with high EVI and high evaporative demand (as estimated from a nearby weather station) correlate with greater water level cycle amplitude and, presumably, vegetation-aquifer interaction. We did not observe any diel signals in the water table data during periods with low leaf cover, casting some doubt on the importance of the previously reported streambed infiltration rate driven cyclicity, however analysis of the near-bed hydraulic gradient data is ongoing and will be compared with residuals of the EVI

  5. Ecophysiology of riparian cottonwood and willow before, during, and after two years of soil water removal.

    Science.gov (United States)

    Hultine, K R; Bush, S E; Ehleringer, J R

    2010-03-01

    Riparian cottonwood/willow forest assemblages are highly valued in the southwestern United States for their wildlife habitat, biodiversity, and watershed protection. Yet these forests are under considerable threat from climate change impacts on water resources and land-use activities to support human enterprise. Stream diversions, groundwater pumping, and extended drought have resulted in the decline of cottonwood/willow forests along many riparian corridors in the Southwest and, in many cases, the replacement of these forests with less desirable invasive shrubs and trees. Nevertheless, ecophysiological responses of cottonwood and willow, along with associated ecohydrological feedbacks of soil water depletion, are not well understood. Ecophysiological processes of mature Fremont cottonwood and coyote willow stands were examined over four consecutive growing seasons (2004-2007) near Salt Lake City, Utah, USA. The tree stands occurred near the inlet of a reservoir that was drained in the spring of 2005 and remained empty until mid-summer of 2006, effectively removing the primary water source for most of two growing seasons. Stem sap flux density (Js) in cottonwood was highly correlated with volumetric soil moisture (theta) in the upper 60 cm and decreased sevenfold as soil moisture dropped from 12% to 7% after the reservoir was drained. Conversely, Js in willow was marginally correlated with 0 and decreased by only 25% during the same period. Opposite patterns emerged during the following growing season: willow had a lower whole-plant conductance (kt) in June and higher leaf carbon isotope ratios (delta13C) than cottonwood in August, whereas k(t) and delta13C were otherwise similar between species. Water relations in both species recovered quickly from soil water depletion, with the exception that sapwood area to stem area (As:Ast) was significantly lower in both species after the 2007 growing season compared to 2004. Results suggest that cottonwood has a greater

  6. Potential effects of four Flaming Gorge Dam hydropower operational scenarios on riparian vegetation of the Green River, Utah and Colorado

    International Nuclear Information System (INIS)

    Four hydropower operational scenarios at Flaming Gorge Dam were evaluated to determine their potential effects on riparian vegetation along the Green River in Utah and Colorado. Data collected in June 1992 indicated that elevation above the river had the largest influence on plant distribution. A lower riparian zone occupied the area between the approximate elevations of 800 and 4,200-cfs flows--the area within the range of hydropower operational releases. The lower zone was dominated by wetland plants such as cattail, common spikerush, coyote willow, juncus, and carex. An upper riparian zone was above the elevation of historical maximum power plant releases from the dam (4,200 cfs), and it generally supported plants adapted to mesic, nonwetland conditions. Common species in the upper zone included box elder, rabbitbrush, grasses, golden aster, and scouring rush. Multispectral aerial videography of the Green River was collected in May and June 1992 to determine the relationship between flow and the areas of water and the riparian zone. From these relationships, it was estimated that the upper zone would decrease in extent by about 5% with year-round high fluctuation, seasonally adjusted high fluctuation, and seasonally adjusted moderate fluctuation, but it would increase by about 8% under seasonally adjusted steady flow. The lower zone would increase by about 13% for both year-round and seasonally adjusted high fluctuation scenarios but would decrease by about 40% and 74% for seasonally adjusted moderate fluctuation and steady flows, respectively. These changes are considered to be relatively minor and would leave pre-dam riparian vegetation unaffected. Occasional high releases above power plant capacity would be needed for long-term maintenance of this relict vegetation

  7. Potential for long-term transfer of dissolved organic carbon from riparian zones to streams in boreal catchments.

    Science.gov (United States)

    Ledesma, José L J; Grabs, Thomas; Bishop, Kevin H; Schiff, Sherry L; Köhler, Stephan J

    2015-08-01

    Boreal regions store most of the global terrestrial carbon, which can be transferred as dissolved organic carbon (DOC) to inland waters with implications for both aquatic ecology and carbon budgets. Headwater riparian zones (RZ) are important sources of DOC, and often just a narrow 'dominant source layer' (DSL) within the riparian profile is responsible for most of the DOC export. Two important questions arise: how long boreal RZ could sustain lateral DOC fluxes as the sole source of exported carbon and how its hydromorphological variability influences this role. We estimate theoretical turnover times by comparing carbon pools and lateral exports in the DSL of 13 riparian profiles distributed over a 69 km(2) catchment in northern Sweden. The thickness of the DSL was 36 ± 18 (average ± SD) cm. Thus, only about one-third of the 1-m-deep riparian profile contributed 90% of the lateral DOC flux. The 13 RZ exported 8.7 ± 6.5 g C m(-2) year(-1) , covering the whole range of boreal stream DOC exports. The variation could be explained by local hydromorphological characteristics including RZ width (R(2) = 0.90). The estimated theoretical turnover times were hundreds to a few thousands of years, that is there is a potential long-lasting supply of DOC. Estimates of net ecosystem production in the RZ suggest that lateral fluxes, including both organic and inorganic C, could be maintained without drawing down the riparian pools. This was supported by measurements of stream DO(14) C that indicated modern carbon as the predominant fraction exported, including streams disturbed by ditching. The transfer of DOC into boreal inland waters from new and old carbon sources has a major influence on surface water quality and global carbon balances. This study highlights the importance of local variations in RZ hydromorphology and DSL extent for future DOC fluxes under a changing climate. PMID:25611952

  8. Potential effects of four Flaming Gorge Dam hydropower operational scenarios on riparian vegetation of the Green River, Utah and Colorado

    Energy Technology Data Exchange (ETDEWEB)

    LaGory, K.E.; Van Lonkhuyzen, R.A. [Argonne National Lab., IL (United States). Ecological Sciences Section

    1995-06-01

    Four hydropower operational scenarios at Flaming Gorge Dam were evaluated to determine their potential effects on riparian vegetation along the Green River in Utah and Colorado. Data collected in June 1992 indicated that elevation above the river had the largest influence on plant distribution. A lower riparian zone occupied the area between the approximate elevations of 800 and 4,200-cfs flows--the area within the range of hydropower operational releases. The lower zone was dominated by wetland plants such as cattail, common spikerush, coyote willow, juncus, and carex. An upper riparian zone was above the elevation of historical maximum power plant releases from the dam (4,200 cfs), and it generally supported plants adapted to mesic, nonwetland conditions. Common species in the upper zone included box elder, rabbitbrush, grasses, golden aster, and scouring rush. Multispectral aerial videography of the Green River was collected in May and June 1992 to determine the relationship between flow and the areas of water and the riparian zone. From these relationships, it was estimated that the upper zone would decrease in extent by about 5% with year-round high fluctuation, seasonally adjusted high fluctuation, and seasonally adjusted moderate fluctuation, but it would increase by about 8% under seasonally adjusted steady flow. The lower zone would increase by about 13% for both year-round and seasonally adjusted high fluctuation scenarios but would decrease by about 40% and 74% for seasonally adjusted moderate fluctuation and steady flows, respectively. These changes are considered to be relatively minor and would leave pre-dam riparian vegetation unaffected. Occasional high releases above power plant capacity would be needed for long-term maintenance of this relict vegetation.

  9. Nitrogen dynamics in the shallow groundwater of a riparian wetland zone of the Garonne, SW France: nitrate inputs, bacterial densities, organic matter supply and denitrification measurements

    Directory of Open Access Journals (Sweden)

    J. M. Sánchez-Pérez

    2003-01-01

    Full Text Available This study highlights the role of interactions between surface and sub-surface water of the riparian zone of a large river (the Garonne, SW France. Information is given about the role of surface water in supplying Dissolved Organic Carbon (DOC to the riparian zone for nitrate removal processes. The densities of bacteria (up to 3.3 106 cell m L-1 in groundwater are strongly conditioned by the water moving during flood events. Total bacterial densities in groundwater were related to surface water bacterial densities. In sediment, total bacteria are attached mainly to fine particles (90% in the fraction Keywords: riparian zone, nitrate removal, spatial variations, alluvial groundwater

  10. Shade Trading: An Emerging Riparian Forest-Based Payment for Ecosystem Services Market in Oregon, USA

    Science.gov (United States)

    Guillozet, Kathleen

    2015-10-01

    This paper describes the regulatory and compliance context for Oregon's emerging ecosystem services (ES) market in riparian shade to meet water quality obligations. In Oregon's market as with many other ES programs, contracts and other regulatory documents not only delimit the obligations and liabilities of different parties, but also constitute a primary mechanism through which ES service delivery is measured. Through a review of compliance criteria I find that under Oregon's shade trades, permittees are held to a number of input-based criteria, which essentially affirm that parties comply with predetermined practices and procedures, and one `pseudo output based' criterion, in which ES delivery is estimated through a model. The case presented in the paper critically engages with the challenges of measuring ES and in assessing the outcomes of ES projects. It places these challenges as interrelated and proposes that market designers, policymakers, and other stakeholders should consider explicit efficacy, efficiency, and equity targets.

  11. Environmental Assessments in the Riparian Corridor of the Colorado River Delta

    Science.gov (United States)

    2001-01-01

    We will develop remote sensing methods to conduct environmental assessments in the riparian corridor of the Colorado River delta, shared by the United States and Mexico. This important regional ecosystem is dependent upon US water flows, yet the most important wildlife habitats are in Mexico. The delta region is poorly known and difficult to monitor on the ground. We will use ground-validated, aerial and satellite methods to develop accurate vegetation and habitat maps and predictive hydrological and vegetation models of this ecosystem in response to US flood releases. The work products will advance our understanding of water resource issues in dryland climates and provide a specific application tool for a critical binational natural resource area.

  12. High flow and riparian vegetation along the San Miguel River, Colorado

    Science.gov (United States)

    Friedman, J.M.; Auble, G.T.

    2000-01-01

    Riparian ecosystems are characterized by abundance of water and frequent flow related disturbance. River regulation typically decreases peak flows, reducing the amount of disturbance and altering the vegetation. The San Miguel River is one of the last relatively unregulated rivers remaining in the Colorado River Watershed. One goal of major landowners along the San Miguel including the Bureau of Land Management and The Nature Conservancy is to maintain their lands in a natural condition. Conservation of an entire river corridor requires an integrated understanding of the variability in ecosystems and external influences along the river. Therefore, the Bureau of Land Management and others have fostered a series of studies designed to catalogue that variability, and to characterize the processes that maintain the river as a whole. In addition to providing information useful to managers, these studies present a rare opportunity to investigate how a Colorado river operates in the absence of regulation.

  13. A Long-term Reach-Scale Monitoring Network for Riparian Evapotranspiration, Rock Creek, Kansas

    Science.gov (United States)

    Rajaram, H.; Solis, J. A.; Whittemore, D. O.; Butler, J. J.; Reboulet, E.; Knobbe, S.; Dealy, M.

    2011-12-01

    Riparian evapotranspiration (RET) is an important component of basin-wide evapotranspiration (ET), especially in subhumid to semi-arid regions, with significant impact on water management and conservation. In narrow riparian zones, typical of much of the subhumid to semi-arid U.S., direct measurement of RET by eddy correlation is precluded by the limited fetch distance of riparian vegetation. Alternative approaches based on water balance analyses have a long history, but their accuracy is not well understood. Factors such as heterogeneity in soil properties and root distributions, and sparse measurements, introduce uncertainties in RET estimates. As part of a larger effort aimed at improving understanding of basin-wide RET using scaling theories, we installed a continuous monitoring system for water balance estimation at the scale of a single (~100 m long) reach along Rock Creek in the Whitewater Basin in central Kansas. The distinguishing features of this site include a vadose zone with fine-grained soils underlain by a phreatic zone of coarse gravel embedded in clay, overlying karst bedrock. Across the width (~40 m) of the riparian zone, we installed one transect of four wells screened at the bottom of the alluvium (6-7 m depth), each accompanied by a soil moisture profiler with capacitance sensors at 4 vertical levels above the local water-table elevation (~2.5 m depth) and a shallow well screened just below the water table. All wells were instrumented with pressure transducers for monitoring water levels. Additional sets of all sensors were installed at the upstream and downstream ends of the study reach. Initial results from the monitoring network suggest significant complexities in the behavior of the subsurface system at the site, including a high degree of heterogeneity. All deep wells show a rapid response to streamflow variations and nearby pumping. However, the shallow water-table wells do not respond rapidly to either. Both the shallow wells and soil

  14. Lower Yakima Valley Wetlands and Riparian Restoration Project. Final environmental assessment

    International Nuclear Information System (INIS)

    Bonneville Power Administration (BPA) proposes to fund that portion of the Washington Wildlife Mitigation Agreement pertaining to the Lower Yakima Valley Wetlands and Riparian Restoration Project (Project) in a cooperative effort with the Yakama Indian Nation and the Bureau of Indian Affairs (BIA). The proposed action would allow the sponsors to secure property and conduct wildlife management activities for the Project within the boundaries of the Yakama Indian Reservation. This Environmental Assessment examines the potential environmental effects of acquiring and managing property for wildlife and wildlife habitat within a large 20, 340 hectare (50, 308 acre) project area. As individual properties are secured for the Project, three site-specific activities (habitat enhancement, operation and maintenance, and monitoring and evaluation) may be subject to further site-specific environmental review. All required Federal/Tribal coordination, permits and/or approvals would be obtained prior to ground disturbing activities

  15. Lower Yakima Valley Wetlands and Riparian Restoration Project. Final Environmental Assessment.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration

    1994-10-01

    Bonneville Power Administration (BPA) proposes to fund that portion of the Washington Wildlife Mitigation Agreement pertaining to the Lower Yakima Valley Wetlands and Riparian Restoration Project (Project) in a cooperative effort with the Yakama Indian Nation and the Bureau of Indian Affairs (BIA). The proposed action would allow the sponsors to secure property and conduct wildlife management activities for the Project within the boundaries of the Yakama Indian Reservation. This Environmental Assessment examines the potential environmental effects of acquiring and managing property for wildlife and wildlife habitat within a large 20, 340 hectare (50, 308 acre) project area. As individual properties are secured for the Project, three site-specific activities (habitat enhancement, operation and maintenance, and monitoring and evaluation) may be subject to further site-specific environmental review. All required Federal/Tribal coordination, permits and/or approvals would be obtained prior to ground disturbing activities.

  16. River temperature processes under contrasting riparian land cover: linking microclimate, heat exchange and water thermal dynamics

    Science.gov (United States)

    Hannah, D. M.; Kantola, K.; Malcolm, I.

    2012-12-01

    River temperature influences strongly growth and survival in salmonid fish, which are often the target of river management strategies. Temperature is controlled by transfers of heat and water to/ from the river system, with land and water management modifying exchanges and consequently thermal regime. In the UK, fisheries managers are promoting riparian forest planting as a climate change adaption measure to reduce water temperature extremes. However, scientific understanding lags behind management and policy needs. Specifically, there is an urgent requirement to determine planting strategies that maximise expected benefits of riparian forest in terms of reduction in maximum water temperature. Scientific knowledge is necessary to underpin conceptual and deterministic models to inform management. To address this research gap, this paper analyses high resolution (15 minute) hydrometeorological data collected over a calendar year in the western Scottish Highlands (Loch Ard) to understand the controls and processes determining river temperature dynamics under open moorland (control), semi-natural woodland and commercial forest. The research programme aims: (1) to characterise spatial and temporal variability in riparian microclimate and stream water temperature regime across forest treatments; (2) to identify the hydrological, climatological and site-specific factors affecting stream temperature; (3) to estimate the energy balance at sites representative of each forest treatment and, thus, yield physical process understanding about dominant heat exchanges driving thermal variability; and (4) to use 1-3 to predict stream temperature sensitivity under different forestry and hydroclimatological scenarios. Results indicated that inter-treatment differences in mean and maximum daily water column temperature were ordered open > semi-natural > commercial during summer, but semi-natural > commercial > open during winter. Minimum water temperature was ordered commercial > semi

  17. [Purification of surface water nitrogen and phosphorus pollutants by Zhalong Riparian Wetland].

    Science.gov (United States)

    Guo, Yue-dong; He, Yan; Deng, Wei; Zhang, Guang-xin; Pan, Ji-hua

    2005-05-01

    The laws of purification of stream nitrogen and phosphorus by riparian wetland was studied by sampling in Long'an Bridge and Shuiku Bridge reaches in Zhalong Wetland. Results from the spatial purifying equations show that two reaches exhibited persistent capability of purification of TP and PO4(3-) through out the seasons of spring, summer and fall, and the purifying coefficient of TP fluctuates from 0.00186 to 0.01175 mg x (L x km)(-1) while the PO4(3-)'s was from 2.5E-4 to 0.00704 mg x (L x km)(-1). As to TN, the purification occured only in the seasons of spring and summer while in fall it experienced accumulation downwards along the streamflow, and the output capability was up to 0.48175 mg x (L x km)(-1). Analysis of effect factors show runoff and input concentration have a certain influence on the purification capability. PMID:16124469

  18. Riparian plant succession in the dam-regulated Colorado River: Why is saltcedar losing?

    International Nuclear Information System (INIS)

    Three modes of plant succession (inhibition, facilitation and tolerance) were tested to explain the replacement of exotic saltcedar (Tamarix ramosissima) by naive phreatophytes in the Colorado River corridor in the Grand Canyon. Dam construction reduced flood frequency and sediment transport, interrupting the open-quotes perpetual successionclose quotes of the pre-dam riparian vegetation and initially allowing saltcedar to proliferate. Inhibition results from direct or indirect competition, but field measurements and experiments demonstrate limited evidence of competitive superiority by naive species over saltcedar in three life stages. Field observations and experiments on germination, physiological responses to gradients and comparative life history analyses demonstrate that saltcedar is a stress tolerant, disturbance specialist in an ecologically stabilized river corridor where safe germination sites are increasingly rare. Altered flood frequency, increased soil coarseness and differential herbivory contribute to succession in this system

  19. Trace element levels in whole blood of riparian villagers of the Brazilian Amazon

    International Nuclear Information System (INIS)

    Monitoring the nutritional status of essential elements is of critical importance in human health. However, trace element concentrations in biological fluids are affected by environmental and physiological parameters, and therefore considerable variations can occur between specific population subgroups. Brazil is a large country with much food diversity. Moreover, dietary habits differ from north to south. As an example, the traditional populations of the Brazilian Amazon basin are heavily dependent on fish, fruits, vegetables and manioc for their daily sustenance. However, very few studies have examined to what extent these diets reflect adequate nutritional status for essential elements. Then, in the present study we have evaluated the levels of some trace elements (Cu, Co, Zn Sr, and Rb) in the whole blood of a riparian Brazilian Amazonian population and estimated the influence of age and gender on levels and inter-element interactions in the same population. For this, 253 subjects, aged 15 to 87, from 13 communities situated on the banks of the Tapajos, one of the major tributaries of the Amazon, were randomly selected. The values found for cobalt, copper and strontium in whole blood are in the same range as in other populations. On the other hand, the levels of rubidium and zinc may be considered higher. Moreover, gender was shown to influence Zn and Cu levels while age influenced the concentrations of Sr and Rb in men and Cu in women. Given the scarcity of studies examining nutritional status in traditional communities of the Amazon, our study is the first to provide relevant insight into trace element values in this region and inter-element interactions. This paper is also of particular importance for future studies looking at the possible protective effects of traditional Amazon riparian diets against mercury intake from fish consumption.

  20. Riparian reforestation: are there changes in soil carbon and soil microbial communities?

    Science.gov (United States)

    Mackay, J E; Cunningham, S C; Cavagnaro, T R

    2016-10-01

    Reforestation of pastures in riparian zones has the potential to decrease nutrient runoff into waterways, provide both terrestrial and aquatic habitat, and help mitigate climate change by sequestering carbon (C). Soil microbes can play an important role in the soil C cycle, but are rarely investigated in studies on C sequestration. We surveyed a chronosequence (0-23years) of mixed-species plantings in riparian zones to investigate belowground (chemical and biological) responses to reforestation. For each planting, an adjacent pasture was surveyed to account for differences in soil type and land-use history among plantings. Two remnant woodlands were included in the survey as indicators of future potential of plantings. Both remnant woodlands had significantly higher soil organic C (SOC) content compared with their adjacent pastures. However, there was no clear trend in SOC content among plantings with time since reforestation. The substantial variability in SOC sequestration among plantings was possibly driven by differences in soil moisture among plantings and the inherent variability of SOC content among reference pastures adjacent to plantings. Soil microbial phospholipid fatty acids (PLFA, an indicator of microbial biomass) and activities of decomposition enzymes (β-glucosidase and polyphenol oxidase) did not show a clear trend with increasing planting age. Despite this, there were positive correlations between total SOC concentration and microbial indicators (total PLFA, fungal PLFA, bacterial PLFA and activities of decomposition enzymes) across all sites. The soil microbial community compositions (explored using PLFA markers) of older plantings were similar to those of remnant woodlands. There was a positive correlation between the soil carbon:nitrogen (C:N) and fungal:bacterial (F:B) ratios. These data indicate that in order to maximise SOC sequestration, we need to take into account not only C inputs, but the microbial processes that regulate SOC cycling

  1. Short-term spatial and temporal variability in greenhouse gas fluxes in riparian zones.

    Science.gov (United States)

    Vidon, P; Marchese, S; Welsh, M; McMillan, S

    2015-08-01

    Recent research indicates that riparian zones have the potential to contribute significant amounts of greenhouse gases (GHG: N2O, CO2, CH4) to the atmosphere. Yet, the short-term spatial and temporal variability in GHG emission in these systems is poorly understood. Using two transects of three static chambers at two North Carolina agricultural riparian zones (one restored, one unrestored), we show that estimates of the average GHG flux at the site scale can vary by one order of magnitude depending on whether the mean or the median is used as a measure of central tendency. Because the median tends to mute the effect of outlier points (hot spots and hot moments), we propose that both must be reported or that other more advanced spatial averaging techniques (e.g., kriging, area-weighted average) should be used to estimate GHG fluxes at the site scale. Results also indicate that short-term temporal variability in GHG fluxes (a few days) under seemingly constant temperature and hydrological conditions can be as large as spatial variability at the site scale, suggesting that the scientific community should rethink sampling protocols for GHG at the soil-atmosphere interface to include repeated measures over short periods of time at select chambers to estimate GHG emissions in the field. Although recent advances in technology provide tools to address these challenges, their cost is often too high for widespread implementation. Until technology improves, sampling design strategies will need to be carefully considered to balance cost, time, and spatial and temporal representativeness of measurements. PMID:26169979

  2. Simulating riparian disturbance: Reach scale impacts on aquatic habitat in gravel bed streams

    Science.gov (United States)

    Davidson, S. L.; Eaton, B. C.

    2015-09-01

    Large wood governs channel morphology, as well as the availability of in-stream habitat, in many forested streams. In this paper, we use a stochastic, physically based model to simulate wood recruitment and in-stream geomorphic processes, in order to explore the influence of disturbance history on the availability of aquatic habitat. Specifically, we consider the effects of fire on a range of stream sizes by varying the rate of tree toppling over time in a simulated forest characterized by a tree height of 30 m. We also consider the effects of forest harvesting with various riparian buffer sizes, by limiting the lateral extent of the riparian stand. Our results show that pulsed inputs of wood increase the availability and variability of physical habitat in the postfire period; reach-averaged pool area and deposit area double in small streams, while side channels increase by over 50% in intermediate-sized channels. By contrast, forest harvesting reduces the availability of habitat within the reach, though the effects diminish with increasing buffer size or stream width; in laterally stable streams the effects are minimal so long as buffer width is large enough for key pieces to be recruited to the reach. This research emphasizes the importance of natural disturbance in creating and maintaining habitat heterogeneity and shows that scenario-based numerical modeling provides a useful tool for assessing the historical range of variability associated with natural disturbance, as well as changes in habitat relevant to fish. It can be also used to inform forest harvesting and management.

  3. Sediment Transport and Deposition in Tidal Riparian Wetlands During Drought Conditions

    Science.gov (United States)

    Renfro, A. A.; Leonard, L. A.; Croft, A. L.

    2004-12-01

    Rates of sediment deposition in coastal riparian wetland are determined, in part, by the amount of sediment available in the flooding waters. In the Lower Cape Fear River (LCFR) estuary in southeastern North Carolina total suspended solids (TSS) are received from three major tributaries: Cape Fear mainstem (CFR), Northeast Cape Fear (NECFR), and Black Rivers (BR). The sediment delivered to the estuary depends on the tributary characteristics and climatological conditions in the watersheds. In coastal North Carolina, two primary types of streams, brown-water and black-water, drain vastly different headwater areas and therefore contrast greatly in the amount of sediment they carry and can potentially deposit in adjacent swamps. TSS concentrations in the brown-water river (Cape Fear River) range from 5-35 mg L-1, but TSS are typically lower (suspended sediment concentrations decreased slightly, but not significantly over time during drought conditions, suggesting a loss of suspended sediment to the wetland surface. During normal conditions TSS and ISS concentrations increased slightly, but not significantly, suggesting inhibited settling or export. Sediment deposition data during the drought was consistent with the flux data indicating deposition did not differ significantly between normal and drought conditions. However, total and inorganic deposition was higher during the drought period. At a swamp adjacent to the NECFR suspended sediment concentrations did not vary relative to high tide for either normal or drought conditions. Sediment trap data indicated little difference in deposition between drought and normal conditions. These results indicate short-term changes in climatological conditions may affect deposition rates in tidal riparian swamps. Additional data are needed to examine the extent of drought effects on deposition.

  4. Fish are central in the diet of Amazonian riparians: should we worry about their mercury concentrations?

    International Nuclear Information System (INIS)

    The Amazon rain forest extends over an area of 7.8x106 km2 in nine countries. It harbors a diverse human population distributed in dense cities and isolated communities with extreme levels of infrastructure. Amazonian forest people, either autochthons or frontier riparians (ribeirinhos) living in isolated areas, share the same environment for survival and nutritional status. The peculiarities of the hydrological cycle determine disease patterns, agricultural conditions, and food availability. Feeding strategies depend heavily on cassava products and fish. These two foods carry toxic substances such as linamarin (naturally present in cassava) and monomethyl mercury (MMHg) (bioconcentrated in fish flesh) that cause neurotoxic diseases in other parts of the world but not in Amazonia, where neurotoxic cases of food origin are rare and not related to these staples. While cassava detoxification processes may partly explain its safe consumption, the Hg concentrations in Amazonian fish are within traditionally safe limits for this population and contribute to an important metabolic interaction with cassava. The gold rush of the 1970s and 1980s brought large-scale environmental disruption and physical destruction of ecosystems at impact points, along with a heavy discharge of metallic Hg. The discharged Hg has not yet impacted on MMHg concentrations in fish or in hair of fish consumers. Hair Hg concentration, used as a biomarker of fish consumption, indicates that the Amazonian riparians are acquiring an excellent source of protein carrying important nutrients, the lack of which could aggravate their existing health problems. Therefore, in a scenario of insufficient health services and an unhealthy environment, food habits based on fish consumption are part of a successful survival strategy and recommendations for changes are not yet justifiable

  5. Effects of Riparian Buffer Vegetation and Width: A 12-Year Longitudinal Study.

    Science.gov (United States)

    King, S E; Osmond, D L; Smith, J; Burchell, M R; Dukes, M; Evans, R O; Knies, S; Kunickis, S

    2016-07-01

    Agricultural contributions of nitrogen are a serious concern for many water resources and have spurred the implementation of riparian buffer zones to reduce groundwater nitrate (NO). The optimum design for buffers is subject to debate, and there are few long-term studies. The objective of this project was to determine the effectiveness over time (12 yr) of buffer types (trees, switchgrass, fescue, native, and a control) and buffer widths (8 and 15 m) by measuring groundwater NO-N and dissolved organic carbon (DOC) trends. At the intermediate groundwater depth (1.5-2.1 m), NO-N reduction effectiveness was 2.5 times greater (46 vs. 16%) for the wider buffer, and, regardless of width, buffer effectiveness increased 0.62% yr. Buffer vegetative type was never statistically significant. In the deep-groundwater depth (2.1-3.5 m), there was no change in NO-N removal over time, although the statistical interaction of width and vegetative type indicated a wide range of removal rates (19-82%). The DOC concentrations were analyzed at the field/buffer and buffer/stream sampling locations. Depending on location position and groundwater sampling depth, DOC concentrations ranged from 1.6 to 2.8 mg L at Year 0 and increased at a rate of 0.13 to 0.18 mg L yr but always remained low (≤5.0 mg L). Greater DOC concentrations in the intermediate-depth groundwater did not increase NO-N removal; redox measurements indicated intermittent reduced soil conditions may have been limiting. This study suggests that riparian buffer width, not vegetation, is more important for NO-N removal in the middle coastal plain of North Carolina for a newly established buffer. PMID:27380072

  6. Landscape geomorphic characteristic impacts on greenhouse gas fluxes in exposed stream and riparian sediments.

    Science.gov (United States)

    Vidon, Philippe; Serchan, Satish

    2016-07-13

    While excessive releases of greenhouse gases (GHG: N2O, CO2, CH4) to the atmosphere due to the burning of fossil fuel remains a concern, we also need to better quantify GHG emissions from natural systems. This study investigates GHG fluxes at the soil-atmosphere interface in a series of 7 stream reaches (riparian zones + exposed streambed sediment) across a range of geomorphic locations from headwaters reaches to lowland wetland reaches. When riparian fluxes (RZ) are compared to fluxes from in-stream locations (IS) under summer baseflow conditions, total CO2-equivalent (CO2eq) emissions are approximately 5 times higher at RZ locations than at IS locations, with most CO2eq driven by CH4 production at RZ locations where wet conditions dominate (headwater wetlands, lowland wetlands). On a gas-by-gas basis, no clear differences in N2O fluxes between RZ and IS locations were observed regardless of locations (headwater vs. lowland reaches), while CO2 fluxes were significantly larger at RZ locations than IS locations. Methane fluxes were significantly higher in wetland-influenced reaches than other reaches for both RZ and IS locations. However, GHG fluxes were not consistently correlated to DOC, DO, NO3(-), NH4(+), or water temperature, stressing the limitations of using water quality parameters to predict GHG emissions at the floodplain scale, at least during summer baseflow conditions. As strategies are developed to further constrain GHG emission for whole watersheds, we propose that approaches linking landscape geomorphic characteristics to GHG fluxes at the soil-atmosphere interface offer a promising avenue to successfully predict GHG emissions in floodplains at the watershed scale. PMID:27306099

  7. A wooded riparian strip set up for nitrogen removal can affect the water flux microbial composition

    Directory of Open Access Journals (Sweden)

    Mizanur Md. Rahman

    2014-02-01

    Full Text Available This research is part of a project aimed at verifying the potential of a specifically assessed wooded riparian zone in removing excess of combined nitrogen from the Zero river flow for the reduction of nutrient input into Venice Lagoon. Specific objectives were pursued to determine seasonal fluctuations of the microbial populations from the input water to a drainage ditch, conveying back the flux into the river after passing through the soil of the wooded riparian strip. The bacterial communities were determined by combined approaches involving cultivation, microscopic methods and DNA based techniques to determine both culturable and total microbial community in water. The results indicate that the size of the bacterial population, including the culturable fraction, increases from the river to the drainage ditch especially on the warm season. The multiple approach here adopted enabled also to demonstrate that the special condition created in the buffer strip supports the development and the metabolism of the microbial community. The nature of the bacterial population, in terms of phylotypes distribution, was investigated by 16S rDNA analysis indicating that the most represented genera belong to Gamma-proteobacteria, which is known to include an exceeding number of important pathogens. In spring, the effect of the buffer strip seems to significantly reduce such a sub-population. The changes observed for the total bacterial community composition become much evident in summer, as revealed by both denaturing gradient gel electrophoresis cluster analysis and by the diversity index calculation. The hydraulic management coupled to the suspension of farming practices and the development of the woody and herbaceous vegetation resulted in a condition suitable for the containment of undesired microbiota (mainly during the spring season while continuing to support denitrification activity (especially throughout the summer as verified by the total nitrogen

  8. Epidemiologic confirmation that fruit consumption influences mercury exposure in riparian communities in the Brazilian Amazon

    International Nuclear Information System (INIS)

    Since deforestation has recently been associated with increased mercury load in the Amazon, the problem of mercury exposure is now much more widespread than initially thought. A previous exploratory study suggested that fruit consumption may reduce mercury exposure. The objectives of the study were to determine the effects of fruit consumption on the relation between fish consumption and bioindicators of mercury (Hg) exposure in Amazonian fish-eating communities. A cross-sectional dietary survey based on a 7-day recall of fish and fruit consumption frequency was conducted within 13 riparian communities from the Tapajos River, Brazilian Amazon. Hair samples were collected from 449 persons, and blood samples were collected from a subset of 225, for total and inorganic mercury determination by atomic absorption spectrometry. On average, participants consumed 6.6 fish meals/week and ate 11 fruits/week. The average blood Hg (BHg) was 57.1±36.3 μg/L (median: 55.1 μg/L), and the average hair-Hg (HHg) was 16.8±10.3 μg/g (median: 15.7 μg/g). There was a positive relation between fish consumption and BHg (r=0.48; P2=36.0%) and HHg levels (fish: β=1.2, P2=21.0%). ANCOVA models showed that for the same number of fish meals, persons consuming fruits more frequently had significantly lower blood and HHg concentrations. For low fruit consumers, each fish meal contributed 9.8 μg/L Hg increase in blood compared to only 3.3 μg/L Hg increase for the high fruit consumers. In conclusion, fruit consumption may provide a protective effect for Hg exposure in Amazonian riparians. Prevention strategies that seek to maintain fish consumption while reducing Hg exposure in fish-eating communities should be pursued

  9. Riverine Landscape Patch Heterogeneity Drives Riparian Ant Assemblages in the Scioto River Basin, USA.

    Directory of Open Access Journals (Sweden)

    Paradzayi Tagwireyi

    Full Text Available Although the principles of landscape ecology are increasingly extended to include riverine landscapes, explicit applications are few. We investigated associations between patch heterogeneity and riparian ant assemblages at 12 riverine landscapes of the Scioto River, Ohio, USA, that represent urban/developed, agricultural, and mixed (primarily forested, but also wetland, grassland/fallow, and exurban land-use settings. Using remotely-sensed and ground-collected data, we delineated riverine landscape patch types (crop, grass/herbaceous, gravel, lawn, mudflat, open water, shrub, swamp, and woody vegetation, computed patch metrics (area, density, edge, richness, and shape, and conducted coordinated sampling of surface-active Formicidae assemblages. Ant density and species richness was lower in agricultural riverine landscapes than at mixed or developed reaches (measured using S [total number of species], but not using Menhinick's Index [DM], whereas ant diversity (using the Berger-Park Index [DBP] was highest in agricultural reaches. We found no differences in ant density, richness, or diversity among internal riverine landscape patches. However, certain characteristics of patches influenced ant communities. Patch shape and density were significant predictors of richness (S: R2 = 0.72; DM: R2=0.57. Patch area, edge, and shape emerged as important predictors of DBP (R2 = 0.62 whereas patch area, edge, and density were strongly related to ant density (R2 = 0.65. Non-metric multidimensional scaling and analysis of similarities distinguished ant assemblage composition in grass and swamp patches from crop, gravel, lawn, and shrub as well as ant assemblages in woody vegetation patches from crop, lawn, and gravel (stress = 0.18, R2 = 0.64. These findings lend insight into the utility of landscape ecology to river science by providing evidence that spatial habitat patterns within riverine landscapes can influence assemblage characteristics of riparian

  10. Diversity of Riparian Plants among and within Species Shapes River Communities.

    Science.gov (United States)

    Jackrel, Sara L; Wootton, J Timothy

    2015-01-01

    Organismal diversity among and within species may affect ecosystem function with effects transmitting across ecosystem boundaries. Whether recipient communities adjust their composition, in turn, to maximize their function in response to changes in donor composition at these two scales of diversity is unknown. We use small stream communities that rely on riparian subsidies as a model system. We used leaf pack experiments to ask how variation in plants growing beside streams in the Olympic Peninsula of Washington State, USA affects stream communities via leaf subsidies. Leaves from red alder (Alnus rubra), vine maple (Acer cinereus), bigleaf maple (Acer macrophyllum) and western hemlock (Tsuga heterophylla) were assembled in leaf packs to contrast low versus high diversity, and deployed in streams to compare local versus non-local leaf sources at the among and within species scales. Leaves from individuals within species decomposed at varying rates; most notably thin leaves decomposed rapidly. Among deciduous species, vine maple decomposed most rapidly, harbored the least algal abundance, and supported the greatest diversity of aquatic invertebrates, while bigleaf maple was at the opposite extreme for these three metrics. Recipient communities decomposed leaves from local species rapidly: leaves from early successional plants decomposed rapidly in stream reaches surrounded by early successional forest and leaves from later successional plants decomposed rapidly adjacent to later successional forest. The species diversity of leaves inconsistently affected decomposition, algal abundance and invertebrate metrics. Intraspecific diversity of leaf packs also did not affect decomposition or invertebrate diversity. However, locally sourced alder leaves decomposed more rapidly and harbored greater levels of algae than leaves sourced from conspecifics growing in other areas on the Olympic Peninsula, but did not harbor greater aquatic invertebrate diversity. In contrast to

  11. Flood impact assessment on the development of Archaia Olympia riparian area in Greece.

    Science.gov (United States)

    Pasaporti, Christina; Podimata, Marianthi; Yannopoulos, Panayotis

    2013-04-01

    A long list of articles in the literature examines several issues of flood risk management and applications of flood scenarios, taking into consideration the climate changes, as well as decision making tools in flood planning. The present study tries to highlight the conversation concerning flood impacts on the development rate of a riparian area. More specifically, Archaia (Ancient) Olympia watershed was selected as a case study area, since it is considered as a region of special interest and international significance. In addition, Alfeios River, which is the longest river of Peloponnisos Peninsula, passes through the plain of Archaia Olympia. Flood risk scenarios allow scientists and practitioners to understand the adverse effects of flooding on development activities such as farming, tourism etc. and infrastructures in the area such as road and railway networks, Flokas dam and the hydroelectric power plant, bridges, settlements and other properties. Flood risks cause adverse consequences on the region of Archaia Olympia (Ancient Olympic stadium) and Natura 2000 site area. Furthermore, SWOT analysis was used in order to quantify multicriteria and socio-economic characteristics of the study area. SWOT analysis, as a planning method, indicates the development perspective by identifying the strengths, weaknesses, threads and opportunities. Subsequent steps in the process of intergraded River Management Plan of Archaia Olympia could be derived from SWOT analysis. The recognition and analysis of hydro-geomorphological influences on riparian development activities can lead to the definition of hazardous and vulnerability zones and special warning equipment. The former information combined with the use of the spatial database for the catchment area of the River Alfeios, which aims to gather multiple watershed data, could serve in preparing the Management Plan of River Basin District 01 where Alfeios R. belongs. Greece has to fulfill the obligation of implementing River

  12. Occurrence and controls on transport and transformation of nitrogen in riparian zones of Dongting Lake, China.

    Science.gov (United States)

    Zhao, Shan; Zhou, Nianqing; Liu, Xiaoqun

    2016-04-01

    Dongting Lake is the second largest freshwater lake in China. It is suffering from significant eutrophication as a result of excessive nutrients inputs, among which nitrogen (N) is becoming a major contributor. The objective of this study is to document the occurrence and controls on N transport and transformation in riparian zones of Dongting Lake wetland. Field experiments were conducted in the cultivated Li River (LR) and uncultivated Yuan River (YR) regions of the wetlands from June to November, 2014. Groundwater depth, redox potential (Eh), pH, and temperature were measured in situ. Groundwater and surface water samples were collected to determine concentrations of nitrate nitrogen (NO3 (-)-N), nitrite nitrogen (NO2 (-)-N), and ammonia nitrogen (NH4 (+)-N). The results showed that NH4 (+)-N was the dominant N pollutant with maximum average value of 2.7760 mg L(-1). All the groundwater samples were rated to Class V based on NH4 (+)-N content according to the groundwater quality standard, indicating the load of N in riparian zones had exceeded their capacity for assimilation and purification. Internal controls (including Eh and pH, temperature, and groundwater depth) and external controls (including surface water, land use, and rainfall) were analyzed in detail. The results suggested that Eh and pH were more significant in controlling N transport and transformation than temperature and groundwater depth; external controls influenced N fates through imposing an effect on internal controls. This study will provide important insights and a scientific basis for N pollution treatment and better protection of the Dongting Lake wetlands. PMID:26635216

  13. Entrainment of riparian gravel and cobbles in an alluvial reach of a regulated canyon river

    Science.gov (United States)

    Elliotp, J.G.; Hammack, L.A.

    2000-01-01

    Many canyon rivers have channels and riparian zones composed of alluvial materials and these reaches, dominated by fluvial processes, are sensitive to alterations in streamflow regime. Prior to reservoir construction in the mid-1960s, banks and bars in alluvial reaches of the Gunnison River in the Black Canyon National Monument, Colorado, USA, periodically were reworked and cleared of riparian vegetation by mainstem floods. Recent interest in maintaining near-natural conditions in the Black Canyon using reservoir releases has created a need to estimate sediment-entraining discharges for a variety of geomorphic surfaces composed of sediment ranging in size from gravel to small boulders. Sediment entrainment potential was studied at eight cross-sections in an alluvial reach of the Gunnison River in the Black Canyon in 1994 and 1995. A one-dimensional water-surface profile model was used to estimate water-surface elevations, flow depths, and hydraulic conditions on selected alluvial surfaces for discharges ranging from 57 to 570 m3/s. Onsite observations before and after a flood of 270 m3/s confirmed sediment entrainment on several surfaces inundated by the flood. Selective entrainment of all but the largest particle sizes on the surface occurred at some locations. Physical evidence of sediment entrainment, or absence of sediment entrainment, on inundated surfaces generally was consistent with critical shear stresses estimated with a dimensionless critical shear stress of 0.030. Sediment-entrainment potential over a range of discharges was summarized by the ratio of the local boundary shear stress to the critical shear stress for d50, given hydraulic geometry and sediment-size characteristics. Differing entrainment potential for similar geomorphic surfaces indicates that estimation of minimum streamflow requirements based on sediment mobility is site-specific and that there is no unique streamflow that will initiate movement of d50 at every geomorphically similar

  14. Riparian Zones, 50 and 100 foot buffers, Published in 2007, 1:1200 (1in=100ft) scale, Town of Cary NC.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Riparian Zones dataset, published at 1:1200 (1in=100ft) scale, was produced all or in part from Hardcopy Maps information as of 2007. It is described as '50...

  15. Using Repeated LIDAR to Characterize Topographic Changes in Riparian Areas and Stream Channel Morphology in Areas Undergoing Urban Development: An Accuracy Assessment Guide for Local Watershed Managers

    Science.gov (United States)

    Urban development and the corresponding increases in impervious surfaces associated with that development have long been known to have adverse impacts upon urban riparian systems, water quality and quantity, groundwater recharge, streamflow, and aquatic ecosystem integrity. The ...

  16. Riparian Zones, Protected River corridors in 9 county region in South Georgia, Published in 1999, 1:7200 (1in=600ft) scale, Southern Georgia Regional Commission.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Riparian Zones dataset, published at 1:7200 (1in=600ft) scale, was produced all or in part from Other information as of 1999. It is described as 'Protected...

  17. Spatial and temporal analysis of the land cover in riparian buffer zones (Areas for Permanent Preservation in Sorocaba City, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Sergio Henrique Alves

    2009-08-01

    Full Text Available Considering the fundamental role that the riparian vegetation plays in relation to maintenance of the environmental health of a watershed and the necessity of restoring sectors of the buffer zone without natural vegetation, in this paper we investigated what land cover classes occur along the riparian buffer stripes considered Area for Permanent Preservation (APP in the Sorocaba municipality, SP in three periods: 1988, 1995 and 2003. Based on GIS technology and using the drainage network map, the APP stripes (riparian buffer zones map was generated, and this map was overlaid to the land cover map (1988, 1995 and 2003 to provide a land cover map specifically of the riparian buffer zones. The results show that 58.43% of the APPs have no land cover of native vegetation and therefore, need to be reforested, representing 5,400 hectares to be restored.

  18. Post-wildfire natural restoration of riparian vegetation under stable hydro-geomorphic conditions: Nahal Grar, Northern Negev Desert, Israel

    Science.gov (United States)

    Egozi, Roey

    2015-04-01

    Wildfires are common to the Mediterranean region due to its defined dry season and long historical anthropogenic activities. Most of post-wildfire studies focus on mountains areas and thus refer to the hill-slope and its physical characteristics, e.g. morphology, length, angles, and aspect; its soil characteristics, e.g. type, infiltration rate, repellency; and its vegetative covers, e.g. planted trees vs. natural forest or native vs. exotic vegetation. In contrary there is very limited literature focusing on ecological and hydro-geomorphic aspects of post-wildfire of riparian vegetation / zone probably because of its negligible burned area relative to the spread of the fire, sometimes, over the whole watershed area. The limited literature on the topic is surprising given the fact that riparian vegetation zone has been acknowledged as a unique and important habitat supporting rich biodiversity. Herein we report on a wildfire event occurred on October 14th 2009 in a river section of Nahal Grar, Northern Negev Desert, Israel. The wildfire although was limited in its area (only 3 hectare) extended over the channel alone from bank to bank and thus provide a unique case study of completely burn down of riparian vegetation, mainly dense stands of Common Red (Australis Phragmites. Therefore a detailed study of this event provides an opportunity to tackle one of the basics questions which is determining the rate of natural restoration process that act at the immediate time after the wildfire event occurred. This type of information is most valuable to professional and stakeholders for better management of post-fire riparian zones. The results of the study suggest that under stable conditions, i.e. no major flood events occurred; disturbance time was short and ranged over 200 days due to, almost, immediate recovery of the riparian vegetation. However the re-growth of the riparian vegetation was not even but rather deferential and more complex then reported in the literature

  19. Riparian forest and permanent groundwater: a key coupling for balancing the hillslope water budget in Sudanian West Africa

    Directory of Open Access Journals (Sweden)

    A. Richard

    2013-05-01

    Full Text Available Forests are thought to play an important role in the regional dynamics of the West African monsoon, through their capacity to extract water from permanent aquifers located deep in the soil and pump it into the atmosphere even during the dry season. This is especially true for riparian forests located at the bottom of the hillslopes. This coupling between the riparian forests and the permanent aquifers is investigated, looking for quantifying its contribution to the catchment water balance. To this end, use is made of the observations available from a comprehensively instrumented hillslope through the framework of the AMMA-CATCH (African Monsoon Multidisciplinary Analysis – Coupling the Tropical Atmosphere and the Hydrological Cycle observing system. Attention is paid to measurements of actual evapotranspiration, soil moisture and deep groundwater level. A vertical 2-D approach is followed using the physically-based Hydrus 2-D model in order to simulate the hillslope hydrodynamics, the model being calibrated and evaluated through a multi-criteria approach. The model correctly simulates the hydrodynamics of the hillslope as far as soil moisture dynamics, deep groundwater fluctuation and actual evapotranspiration dynamics are concerned. In particular, the model is able to reproduce the observed hydraulic disconnection between the deep permanent groundwater table and the river. A virtual experiment shows that the riparian forest depletes the deep groundwater table level through transpiration occurring throughout the year so that the permanent aquifer and the river are not connected. Moreover the riparian forest and the deep groundwater table form a coupled transpiration system: the riparian forest transpiration is due to the water redistribution at the hillslope scale feeding the deep groundwater through lateral saturated flow. The annual cycle of the transpiration origin is also quantified. The riparian forest which covers only 5% of the

  20. Influence of the land use and land cover on the water quality: a method to evaluate the importance of riparian zones

    OpenAIRE

    Teresinha Guerra; Iuri Buffon; Raul Candido da Trindade Paixão Coelho

    2011-01-01

    The riparian ecosystem constitutes an interface among the terrestrial and aquatic environments in a watershed. The human impact on drainage basins influences the organisms and the quality of the running water. The objective of this paper was to evaluate the effect of this impact, taking into account the different land use classes of the drainage basins and of the riparian areas in the quality of the water. Land use and land cover of the watershed were classified based on the interpretation of...

  1. Do Adaptive Comanagement Processes Lead to Adaptive Comanagement Outcomes? A Multicase Study of Long-term Outcomes Associated with the National Riparian Service Team's Place-based Riparian Assistance

    Directory of Open Access Journals (Sweden)

    Jill A. Smedstad

    2013-12-01

    Full Text Available Adaptive comanagement (ACM is a novel approach to environmental governance that combines the dynamic learning features of adaptive management with the linking and network features of collaborative management. There is growing interest in the potential for ACM to resolve conflicts around natural resource management and contribute to greater social and ecological resilience, but little is known about how to catalyze long lasting ACM arrangements. We contribute to knowledge on this topic by evaluating the National Riparian Service Team's (NRST efforts to catalyze ACM of public lands riparian areas in seven cases in the western U.S. We found that the NRST's approach offers a relatively novel model for integrating joint fact-finding, multiple forms of knowledge, and collaborative problem solving to improve public lands riparian grazing management. With this approach, learning and dialogue often helped facilitate the development of shared understanding and trust, key features of ACM. Their activities also influenced changes in assessment, monitoring, and management approaches to public lands riparian area grazing, also indicative of a transition to ACM. Whereas these effects often aligned with the NRST's immediate objectives, i.e., to work through a specific issue or point of conflict, there was little evidence of long-term effects beyond the specific issue or intervention; that is, in most cases the initiative did not influence longer term changes in place-based governance and institutions. Our results suggest that the success of interventions aimed at catalyzing the transformation of governance arrangements toward ACM may hinge on factors external to the collaborative process such as the presence or absence of (1 dynamic local leadership and (2 high quality agreements regarding next steps for the group. Efforts to establish long lasting ACM institutions may also face significant constraints and barriers, including existing laws and regulations

  2. Vegetation development following stream/river restoration: more natural fluvial dynamics and morphology, return of aquatic and riparian plant species?

    Science.gov (United States)

    Soons, M. B.

    2012-04-01

    After centuries of human interventions in stream/river dynamics and morphology aimed at optimizing landscapes for agricultural and industrial purposes, new insights have inspired water managers to try and combine stream and river ecosystem functions with the conservation of biodiversity. Around the world, aquatic and riparian species have declined strongly due to pollution, destruction and fragmentation of their habitat, so that biodiversity conservation initiatives primarily focus on habitat restoration. In the past decades many stream and river restoration projects have been carried out and often hydrological dynamics and morphology have been restored to a more natural state. However, the successful restoration of aquatic and riparian habitats very often failed to result in restoration of their biodiversity. This lack of success from a biodiversity conservation perspective is usually attributed to 'dispersal limitation', meaning that the habitat may be restored, but species fail to reach the site and re-colonize it. Especially re-colonization by aquatic and riparian plant species is important, as such species function as ecosystem engineers: their presence alters fluvial dynamics and morphology, generates additional habitat heterogeneity and provides habitat and food for animal species. Following minor disturbances, re-colonization is often possible through locally remaining populations, by seeds in the seed bank or by surviving plant fragments. However, following major disturbances, colonization and establishment from other source populations are necessary. This usually occurs through dispersal of seeds (and in more aquatic species also by dispersal of vegetative fragments) into the restored wetland area. As dispersal occurs predominantly over short distances and source populations of aquatic and riparian species may be lacking in the surroundings, dispersal may be a limiting factor in the development of aquatic and riparian vegetation at a restored site. But

  3. Ecological Dose Modeling of Aquatic and Riparian Receptors to Strontium-90 with an Emphasis on Radiosensitive Organs

    Energy Technology Data Exchange (ETDEWEB)

    Poston, Ted M.; Traub, Richard J.; Antonio, Ernest J.

    2011-07-20

    The 100-NR-2 site is the location of elevated releases of strontium-90 to the Columbia River via contaminated groundwater. The resulting dose to aquatic and riparian receptors was evaluated in 2005 (DOE 2009) and compared to U.S. Department of Energy (DOE) dose guidance values. We have conducted additional dose assessments for a broader spectrum of aquatic and riparian organisms using RESRAD Biota and specific exposure scenarios. Because strontium-90 accumulates in bone, we have also modeled the dose to the anterior kidney, a blood-forming and immune system organ that lies close to the spinal column of fish. The resulting dose is primarily attributable to the yttrium-90 progeny of strontium-90 and very little of the dose is associated with the beta emission from strontium-90. All dose modeling results were calculated with an assumption of secular equilibrium between strontium-90 and yttrum-90.

  4. Decreased carbon and nutrient input to boreal lakes from particulate organic matter following riparian clear-cutting

    Science.gov (United States)

    France, Robert; Culbert, Heather; Peters, Robert

    1996-07-01

    The plankton communities of oligotrophic Canadian Shield lakes are strongly regulated by the allochthonous supply of total phosphorus (TP) and dissolved organic carbon (DOC), a proportion of both of which originate from particulate organic matter. Although decreased inputs of allochthonous leaf litter have been documented for small streams whose riparian forests have been removed, no such data exist for boreal lakes. Through estimates of airborne litter input from forested and clear-cut shorelines and laboratory measurements of concentrations released from leaf leachate, we determined that riparian deforestation resulted in reductions of DOC from 17.8 to 0.4 g/m shoreline/yr and of TP from 2.9 to 0.3 g/m shoreline/yr. Previous predictive models indicate that such reductions may be substantial enough to decrease basic metabolic processes of lake plankton communities by as much as 9% in primary production and 17% in respiration.

  5. Variability in riparian zone potential and actual evapotranspiration in a 1st order agricultural catchment in Southern Ontario, Canada

    Directory of Open Access Journals (Sweden)

    M. C. English

    2002-02-01

    Full Text Available Micrometeorological and hydrological measurements were made over one growing season using automatic weather stations and weighing lysimeters at several locations within a multiple land-use agricultural catchment in Southern Ontario. This paper compares modelled potential evapotranspiration (PET and measured actual evapotranspiration (AET values obtained from the soil weighing lysimeters, and determines the spatial variability in riparian zone AET in a multiple land-use agricultural watershed in Southern Ontario. Two sites were chosen in two different riparian areas of the watershed, representing the surface conditions dominant in the upper and lower reaches of the basin. The results indicated that AET was higher in the northern end of the basin than in the southern portion of the basin, while the hydrological and energy balance components were similar at both sites. The causes of the different rates are attributed to the surrounding vegetation on adjacent fields and the differing wind regimes.

  6. The effect of macropores on bi-directional hydrologic exchange between a stream channel and riparian groundwater

    Science.gov (United States)

    Menichino, Garrett T.; Hester, Erich T.

    2015-10-01

    Macropores and soil pipes in stream banks are common geomorphic features. Macropores and soil pipes that are open to the channel (i.e. "bank face-connected" macropores) are inundated when channel stage is elevated (e.g., from precipitation, snowmelt, dam release). However, previous studies have not investigated macropore impact on bi-directional water exchange between the channel and bank/riparian groundwater under variable hydrologic conditions. We monitored two transects of riparian groundwater wells perpendicular to the bank of a 2nd order stream for a year: one with bank face-connected macropores (M transect) and one without bank face-connected macropores (NM transect). Fluctuations in water level and temperature during storms in those wells closest to the channel were on average 139% and 29% higher, respectively, in the presence of macropores. Rising head tests in the same wells indicated that hydraulic conductivity was 61-140 times higher in the presence of macropores. Bank storage, indicated by gradient reversals between channel and riparian zone, occurred on two temporal scales. Bank storage during storms was more frequent in the M transect (occurred all year) than in the NM transect (occurred just in winter and spring). Smaller magnitude gradient reversals at the M transect are consistent with faster head equilibration and greater exchange volume. Bank storage also occurred on an annual basis, with channel water entering storage during summer and fall and returning to the channel during winter and spring. Taken together, these results suggest that macropores act as preferential flow paths that enhance the connectivity between channels and riparian groundwater that influences bank storage. Where bank macropores are present, conceptual models of hyporheic and groundwater flow should account for their effects.

  7. Potential for Hybrid Poplar Riparian Buffers to Provide Ecosystem Services in Three Watersheds with Contrasting Agricultural Land Use

    OpenAIRE

    Julien Fortier; Benoit Truax; Daniel Gagnon; France Lambert

    2016-01-01

    In temperate agricultural watersheds, the rehabilitation of tree vegetation in degraded riparian zones can provide many ecosystem services. This study evaluated ecosystem service provision potential following the conversion of non-managed herbaceous buffers to hybrid poplar (Populus spp.) buffers in three watersheds (555–771 km2) of southern Québec (Canada), with contrasting agricultural land uses. To extrapolate services at the watershed level, total stream length where hybrid poplars could ...

  8. Variability in riparian zone potential and actual evapotranspiration in a 1st order agricultural catchment in Southern Ontario, Canada

    OpenAIRE

    R. M. Petrone; Smith, C.; English, M C

    2005-01-01

    Micrometeorological and hydrological measurements were made over one growing season using automatic weather stations and weighing lysimeters at several locations within a multiple land-use agricultural catchment in Southern Ontario. This paper compares modelled potential evapotranspiration (PET) and measured actual evapotranspiration (AET) values obtained from the soil weighing lysimeters, and determines the spatial variability in riparian zone AET in a multiple land-use agr...

  9. The effects of riparian forestry on invertebrate drift and brown trout in upland streams of contrasting acidity

    Science.gov (United States)

    Ormerod, S. J.; Jones, M. E.; Jones, M. C.; Phillips, D. R.

    Variations in macroinvertebrate drift and benthic invertebrate abundance were assessed in 30 upland Welsh streams of varying acidity (pH 6.0) and riparian land-use (conifer, moorland or native broadleaf). The consequences for the diet and condition of wild brown trout Salmo trutta were also assessed. As expected from previous studies, there were significant reductions in benthic invertebrate abundance, aquatic drift density (by >60%), aquatic drift biomass (by >35%), total drift density (by >35%) and total drift biomass (by >20%) at acid sites by comparison with circumneutral sites due largely to the scarcity of mayflies. Absolute drift from terrestrial sources was unrelated to stream pH but formed a significantly greater proportion of total drift at acid sites (30-65% of density) than at circumneutral sites (20-40%) as aquatic contributions declined. Most of this apparent land use effect reflected significantly increased terrestrial drift under broadleaves. There was no significant reduction in terrestrial or aquatic drift at conifer forest sites per se after accounting for low pH. Trout diet varied substantially between locations partly reflecting variations in drift: significantly fewer mayflies and stoneflies were eaten at acid sites, and significantly more terrestrial prey were eaten under broadleaves. However, acidity did not reduce trout condition or gut-fullness. Unexpectedly, trout condition was significantly enhanced at conifer sites, irrespective of their pH. Hence, acidity has greater effects on the benthic abundance and drift density of invertebrates in upland streams than does riparian land use. However, trout forage flexibly enough to offset any possible food deficit, for example by switching to chironomids and terrestrial invertebrates. Enhanced terrestrial contributions to invertebrate drift from riparian broadleaf trees may be important in supplementing foraging opportunities for trout where aquatic prey are scarce. These data illustrate the value

  10. Leaf litter dynamics and nitrous oxide emission in a Mediterranean riparian forest: implications for soil nitrogen dynamics.

    Science.gov (United States)

    Bernal, S; Butturini, A; Nin, E; Sabater, F; Sabater, S

    2003-01-01

    Mediterranean riparian zones can experience severe drought periods that lead to low soil moisture content, which dramatically affects their performance as nitrate removal systems. In the Mediterranean riparian zone of this study, we determined that N2O emission was practically nil. To understand the role of forest floor processes in nitrogen retention of a Mediterranean riparian area, we studied leaf litter dynamics of two tree species, London planetree [Platanus x acerifolia (Aiton) Willd.] and alder [Alnus glutinosa (L.) Gaertn.], for two years, along with soil nitrogen mineralization rates. Annual leaf litter fall equaled 562.6 +/- 10.1 (standard error) g dry wt. m(-2), 68% of which was planetree and 32% of which was alder. The temporal distribution of litterfall showed a two-peak annual cycle, one occurring in midsummer, the other in autumn. Planetree provided the major input of organic nitrogen to the forest floor, and the amount of planetree leaves remaining on the forest floor was equivalent to approximately four years of stock. Leaf litter decomposition was three times higher for alder (decay coefficient [k] = 1.13 yr(-1)) than for planetree (k = 0.365 yr(-1)). Mineralization rates showed a seasonal pattern, with the maximum rate in summer (1.92 mg N kg(-1) d(-1)). Although the forest floor was an important sink for nitrogen due to planetree leaf accumulation, 7.5% of this leaf litter was scoured to the streambed by wind. This loss was irrelevant for alder leaves. Due to the litter quality, the forest floor of this Mediterranean riparian forest acts as a nitrogen sink. PMID:12549558

  11. Evaluation of an extreme-condition-inverse calibration remote sensing model for mapping energy balance fluxes in arid riparian areas

    OpenAIRE

    Hong, S.-H.; Hendrickx, J. M. H.; Kleissl, J.; Allen, R.G.; W. G. M. Bastiaanssen; R. L. Scott; A. L. Steinwand

    2014-01-01

    Accurate information on the distribution of the surface energy balance components in arid riparian areas is needed for sustainable management of water resources as well as for a better understanding of water and heat exchange processes between the land surface and the atmosphere. Since the spatial and temporal distributions of these fluxes over large areas are difficult to determine from ground measurements alone, their prediction from remote sensing data is ...

  12. Interaction of Bar Morphology and Riparian Vegetation in Gravel-Bed Rivers

    Science.gov (United States)

    Francalanci, S.; Bertoldi, W.; Siviglia, A.; Solari, L.; Toffolon, M.; Vetsch, D.

    2013-12-01

    Gravel-bed rivers are often characterized by complex bed topography, including single- and multiple-row alternate bars, bed undulations associated with channel curvature, riffle and pool sequences, presence of riparian vegetation in the floodplain, etc. The interaction of these features results in different morphologies with complex patterns and dynamics. The present work investigates the effect of the riparian vegetation on the bar dynamics, in particular it is investigated how the vegetation, which grows during the dry season on the bars, can alter the topographic patterns evolution during flood conditions. Performing two-dimensional numerical simulations we try to answer to the following research questions: which is the interaction of vegetation with bar morphology? which are the changes in sediment discharge and flow resistance, at cross-sectional and reach scale? Which are the changes in distribution of emerged and submerged areas, and potential feedbacks for vegetation growth? Which is the effect of vegetation on bar wave-length? The code BASEMENT (Faeh et al., 2010) has been used for performing the numerical runs. It has been properly modified in order to deal with the numerical description of the vegetation. The vegetation was allowed to grow during the dry season on the top of dry emergent areas, and the vertical distribution of vegetation in equilibrium condition was modeled as a function of the bed elevation using a simple analytical formulation, following Marani et al (2013). Then, during the flood events we assume that the vegetation distribution does not change, and that it can only be uprooted if the bed is eroded.The flow resistance was divided into a resistance exerted by the soil and a resistance exerted by the plants (Crosato and Saleh, 2010; Li and Millar, 2011); in this way it was possible to reproduce both the decrease in bed shear stress, reducing the sediment transport capacity of the flow within the plants, and the increase in hydraulic

  13. Delineating forested river habitats and riparian floodplain hydrology with LiDAR

    Science.gov (United States)

    Vondrasek, Chris

    Rivers and the riparian forest corridor comprise a valuable freshwater ecosystem that has been altered by human activities including timber management, road building, and other land conversions. The habitats of river dependent species in the Pacific Northwest, in particular salmon have often been degraded by these activities. Many salmon runs have become threatened with extinction and have been Endangered Species Act listed. New conservation planning and policies have developed around protecting freshwater habitats and restoring more natural river processes. In WA State, timber landowners, officials from State and Federal agencies, Native tribes, and other stakeholders developed Forest Practice rules and codified a Habitat Conservation Plan with dual goals of providing regulatory surety for timber land owners and helping to recover the threatened salmon runs in forested watersheds. Conserving critical stream ecological functions and potential fish habitats throughout watersheds while managing and regulating timber harvest across the State requires accurate and up-to-date delineation and mapping of channels, tributaries, and off-channel wetlands. Monitoring the effectiveness of protection efforts is necessary but can also be difficult. Agency staff and resources are limited for both day-to-day implementation of Forest Practice rules and adaptive management. The goal of this research has been to develop efficient and accessible methods to delineate wetlands, side-channels, tributaries, and pools and backwaters created by large log jams in forested watersheds. It was also essential to use publicly available LiDAR data and to model these waters at ecologically meaningful flows. I tested a hydraulic model at a 2-year and 50-year flows, and a relative height above river surface model and compared them. I completed two additional remote sensing investigations to correlate channel movement and the locations of off-channel wetlands: an analysis of historical aerial imagery

  14. Catchment controls on water temperature and the development of simple metrics to inform riparian zone management

    Science.gov (United States)

    Johnson, Matthew; Wilby, Robert

    2015-04-01

    of thermal refuge could be important in the context of future climate change, potentially maintaining populations of animals excluded from other parts of the river during hot summer months. International management strategies to mitigate rising temperatures tend to focus on the protection, enhancement or creation of riparian shade. Simple metrics derived from catchment landscape models, the heat capacity of water, and modelled solar radiation receipt, suggest that approximately 1 km of deep riparian shading is necessary to offset a 1° C rise in temperature in the monitored catchments. A similar value is likely to be obtained for similar sized rivers at similar latitudes. Trees would take 20 years to attain sufficient height to shade the necessary solar angles. However, 1 km of deep riparian shade will have substantial impacts on the hydrological and geomorphological functioning of the river, beyond simply altering the thermal regime. Consequently, successful management of rising water temperature in rivers will require catchment scale consideration, as part of an integrated management plan.

  15. Airborne Laser Swath Mapping (ALSM) for Enhanced Riparian Water Use Estimates, Basin Sediment Budgets, and Terrain Characterization

    Science.gov (United States)

    Goodrich, D. C.; Farid, A.; Miller, S. N.; Semmens, D.; Williams, D. J.; Moran, S.; Unkrich, C. L.

    2003-12-01

    The uses of Airborne Laser Swath Mapping (ALSM) or LIDAR for earth science applications beyond topographic mapping are rapidly expanding. The USDA-ARS Southwest Watershed Research Center, in collaboration with the Geosensing Systems Engineering Group at the Univ. of Florida and a wide range of other investigators, designed and conducted a multi-purpose ALSM mission over southeastern Arizona. Research goals include: 1) differentiate young and old riparian cottonwood trees to improve riparian water use estimates; 2) assess the ability of LIDAR to define channel bank steepness and thus cross-channel trafficability; 3) assess the ability of LIDAR to define relatively small, isolated depressions where higher soil moisture may persist; and, 4) quantify changes in channel morphology and sediment movement between pre- and post-monsoon flights. The first flight mission was successfully completed in early June and a post-monsoon mission is scheduled for October. Research goals, mission planning, and initial results will be further developed in this presentation. Acknowledgements: The Upper San Pedro Partnership, DOD-Legacy Program, EPA-Landscape Ecology Branch, U.S. Army-TEC, and the Bureau of Land Management are gratefully acknowledged for supporting this effort. The second author is supported by SAHRA (Sustainability of semi-Arid Hydrology and Riparian Areas) under the STC Program of the National Science Foundation, Agreement No. EAR-9876800.

  16. Spatial and temporal variability in nitrous oxide and methane emissions in urban riparian zones of the Pearl River Delta.

    Science.gov (United States)

    Zhang, Taiping; Huang, Xinyu; Yang, Yue; Li, Yuelin; Dahlgren, Randy A

    2016-01-01

    Spatial and temporal variability in nitrous oxide and methane emissions were quantified in three seasons using closed chambers in three riparian zone locations of three branches of the Pearl River, Guangzhou, China. The sampling sites were selected in a rapidly developing urban area of Guangzhou and represented a pollution gradient. The results show that urban riparian landscapes can be large source areas for CH4 and N2O, with fluxes of -0.035∼32.30 mg m(-2) h(-1) and -5.49∼37.31 μg m(-2) h(-1), respectively. River water quality, sediment texture, and NH4-N and NO3-N concentrations correlated with N2O and CH4 emission rates. The riparian zones of the more seriously polluted tributaries showed higher greenhouse gas fluxes than that of the less polluted main stem of the Pearl River. Rain events increased emissions of CH4 by 6.5∼21.3 times and N2O by 2.2∼5.7 times. The lower concentrations of heavy metals increased the activity of denitrifying enzymes while inhibited the methane producing pathways. This work demonstrates that rapidly developing urban areas are an important source of greenhouse gas emissions, which is conditioned by various environmental factors. PMID:26377967

  17. Caloric content of leaves of five tree species from the riparian vegetation in a forest fragment from South Brazil

    Directory of Open Access Journals (Sweden)

    Leandro Fabrício Fiori

    2015-09-01

    Full Text Available Abstract Aim: The measurement of the caloric content evidences the amount of energy that remains in the leaf and that can be released to the aquatic trophic chain. We assessed the energy content of leaves from five riparian tree species of a forest fragment in south Brazil and analyzed whether leaf caloric content varied between leaf species and between seasons (dry and wet. The studied sites are located in Northwest of Paraná State, inside a Semi-Deciduous Forest fragment beside two headwater streams. Methods Sampling sites were located along the riparian vegetation of these two water bodies, and due to its proximity and absence of statistical differences of caloric values, analyzed as one compartment. Results Caloric content varied significantly among species and among all pairs of species, with exception of Nectandra cuspidata Ness and Calophyllum brasiliensis Cambess. Two species presented significant differences between seasons, Sloanea guianensis (Aubl. Ben and Calophyllum brasiliensis Cambess. Conclusions The absence of significant seasonal differences of energy content for some species may be due to the characteristics of the tropical forest, in which temperature did not varied dramatically between seasons. However, the energy differed between species and seasons for some species, emphasizing the necessity of a preliminary inspection of energy content, before tracing energy fluxes instead of using a single value to all species from riparian vegetation.

  18. The influence of riparian woodland on the spatial and temporal variability of stream water temperatures in an upland salmon stream

    Directory of Open Access Journals (Sweden)

    I. A. Malcolm

    2004-01-01

    Full Text Available The spatio-temporal variability of stream water temperatures was investigated at six locations on the Girnock Burn (30km2 catchment, Cairngorms, Scotland over three hydrological years between 1998 and 2002. The key site-specific factors affecting the hydrology and climatology of the sampling points were investigated as a basis for physical process inference. Particular emphasis was placed on assessing the effects of riparian forest in the lower catchment versus the heather moorland riparian zones that are spatially dominant in the upper catchment. The findings were related to river heat budget studies that provided process detail. Gross changes in stream temperature were affected by the annual cycle of incoming solar radiation and seasonal changes in hydrological and climatological conditions. Inter-annual variation in these controlling variables resulted in inter-annual variability in thermal regime. However, more subtle inter-site differences reflected the impact of site-specific characteristics on various components of the river energy budget. Inter-site variability was most apparent at shorter time scales, during the summer months and for higher stream temperatures. Riparian woodland in the lower catchment had a substantial impact on thermal regime, reducing diel variability (over a period of 24 hours and temperature extremes. Observed inter-site differences are likely to have a substantial effect on freshwater ecology in general and salmonid fish in particular. Keywords: temperature, thermal regime, forest, salmon, hydrology, Girnock Burn, Cairngorm

  19. Evaluation of an extreme-condition-inverse calibration remote sensing model for mapping energy balance fluxes in arid riparian areas

    Directory of Open Access Journals (Sweden)

    S.-H. Hong

    2014-12-01

    Full Text Available Accurate information on the distribution of the surface energy balance components in arid riparian areas is needed for sustainable management of water resources as well as for a better understanding of water and heat exchange processes between the land surface and the atmosphere. Since the spatial and temporal distributions of these fluxes over large areas are difficult to determine from ground measurements alone, their prediction from remote sensing data is very attractive as it enables large area coverage and a high repetition rate. In this study the Surface Energy Balance Algorithm for Land (SEBAL was used to estimate all the energy balance components in the arid riparian areas of the Middle Rio Grande Basin (New Mexico, San Pedro Basin (Arizona, and Owens Valley (California. We compare instantaneous and daily SEBAL fluxes derived from Landsat TM images to surface-based measurements with eddy covariance flux towers. This study presents evidence that SEBAL yields reliable estimates for actual evapotranspiration rates in riparian areas of the southwestern United States. The great strength of the SEBAL method is its internal calibration procedure that eliminates most of the bias in latent heat flux at the expense of increased bias in sensible heat flux.

  20. Valuing riparian forests restoration: a CVM application in Corumbatai river basin

    Directory of Open Access Journals (Sweden)

    Caetano Brugnaro

    2010-09-01

    Full Text Available This study is an application of CVM to a specific area in Brazil, the Corumbatai river basin, in the state of Sao Paulo, aiming to estimate the value attached by affected people to a hypothetical riparian forest restoration project. The method used was the double bounded dichotomous choice under a logit model. Data were obtained by street-intercept interviews with a net sample of 930 individuals, 20 years or older, living in seven municipalities (cities and respective rural areas that contain the basin. Protest bid responses were not excluded in a first approximation, resulting in a R$ 2.06 mean willingness to pay (WTP for the riparian forest restoration, equivalent to approximately R$ 274,000 per month (R$ 1.00 equivalent to US$ 0.52 at the survey period when accounting for about 133,000 residences in the area. It was observed an expressive number of "no-no" responses from people ascribing the problem to government and farmers and suspecting on misuse of funds by the official agencies involved.Para este estudo, foi aplicado o CVM (Contingent Valuation Method a uma área específica do Brasil, a bacia do rio Corumbataí, no estado de São Paulo, visando estimar o valor atribuído pela população afetada a um hipotético projeto de reposição de matas ciliares. O método utilizado foi o de escolha dicotômica com limite duplo, sob o modelo da distribuição logística. Os dados foram obtidos por meio de entrevistas nas ruas, numa amostra líquida de 930 pessoas com 20 anos ou mais, moradoras de sete municípios que englobam a bacia. Numa primeira aproximação, não se excluíram as manifestações de protesto, resultando em R$ 2,06 como valor médio da disposição a pagar pela reposição de matas ciliares, o que equivale a aproximadamente R$ 274 mil por mês, quando computadas as aproximadamente 133 mil residências na área. Observou-se um grande número de respostas "não-não" de pessoas que atribuem o problema ao governo e agricultores e

  1. Coupled biogeochemical cycles in riparian zones with contrasting hydrogeomorphic characteristics in the US Midwest

    Science.gov (United States)

    Liu, X.

    2012-12-01

    In this study we aims to understand what drives the fate and transport of multiple contaminants sensitive to soil redox condition across hydrogeomorphic (HGM) gradient and evaluate overall biogeochemical functions of riparian zones regarding those contaminants. We conducted monthly field work for 19 consecutive months from November 2009 to May 2011 at three study sites representative for main HGM types at the US Midwest. We collected the parameters from different sources which include field parameters, such as topography, water table depth, oxidation reduction potential (ORP) and dissolved oxygen (DO), and groundwater chemistry, such as NH4+, NO3-, PO43-, SO42-, CI- , and Hg and MeHg. Our results demonstrated that seasonal water table fluctuations and groundwater flows characteristics at three sites are strongly affected by their HGM setting. Specifically, the convergence of quick rise of water table, high ORP and sharp decrease in concentrations of NO3- and SO42 from field edge to stream edge (60-90% at LWD and 90% at WR) in spring after snowmelt and early May, which could be explained by that snow melt and early summer rainfall are major drivers of fluctuations of water table, variations of ORP and transport and transformation of contaminants. Riparian zones removed NO3- and SO42- during high water table but released Mercury in summer at both LWD and WR, and sulfate reduction, ammonia production and MeHg production all occurred when ORP and water tables were low in summer. These results might reflect the strong ORP control on these processes at landscape scale. These findings supported our hypothesis. Other findings however contrast to our hypothesis. For instances, unusual high concentrations of nitrate and Hg at WR suggest that the transport and fate of multiple contaminants relate not only to HGM settings but geographic location and land use. Negligible variations of P concentration in groundwater indicate that the transformation of P is not sensitive to soil

  2. Riparian forest as a management tool for moderating future thermal conditions of lowland temperate streams

    Directory of Open Access Journals (Sweden)

    P. B. Kristensen

    2013-05-01

    Full Text Available Predictions of the future climate infer that stream water temperatures may increase in temperate lowland areas and that streams without riparian forest will be particularly prone to elevated stream water temperature. Planting of riparian forest is a potential mitigation measure to reduce water temperatures for the benefit of stream organisms. However, no studies have yet determined the length of a forested reach required to obtain a significant temperature decrease. To investigate this we measured the temperature in five small Danish lowland streams from June 2010 to July 2011, all showing a sharp transition between an upstream open reach and a downstream forested reach. In all stream reaches we also measured canopy cover and a range of physical variables characterizing the streams reaches. This allowed us to analyse differences in mean daily temperature and amplitude per month among forested and open sections as well as to study annual temperature regimes and the influence of physical conditions on temperature changes. Stream water temperature in the open reaches was affected by heating, and in July we observed an increase in temperature over the entire length of the investigated reaches, reaching temperatures higher than the incipient lethal limit for brown trout. Along the forest reaches a significant decrease in July temperatures was recorded immediately (100 m when the stream moved into the forested area. In three of our study streams the temperature continued to decrease the longer the stream entered into the forested reach, and the temperature decline did not reach a plateau. The temperature increases along the open reaches were accompanied by stronger daily temperature variation; however, when the streams entered into the forest, the range in daily variation decreased. Multiple regression analysis of the combined effects on stream water temperature of canopy cover, Width/Depth ratio, discharge, current velocity and water temperature

  3. Perceptions of environmental change and use of traditional knowledge to plan riparian forest restoration with relocated communities in Alcântara, Eastern Amazon

    Science.gov (United States)

    2014-01-01

    Background Riparian forests provide ecosystem services that are essential for human well-being. The Pepital River is the main water supply for Alcântara (Brazil) and its forests are disappearing. This is affecting water volume and distribution in the region. Promoting forest restoration is imperative. In deprived regions, restoration success depends on the integration of ecology, livelihoods and traditional knowledge (TEK). In this study, an interdisciplinary research framework is proposed to design riparian forest restoration strategies based on ecological data, TEK and social needs. Methods This study takes place in a region presenting a complex history of human relocation and land tenure. Local populations from seven villages were surveyed to document livelihood (including ‘free-listing’ of agricultural crops and homegarden tree species). Additionally, their perceptions toward environmental changes were explored through semi-structured interviews (n = 79). Ethnobotanical information on forest species and their uses were assessed by local-specialists (n = 19). Remnants of conserved forests were surveyed to access ecological information on tree species (three plots of 1,000 m2). Results included descriptive statistics, frequency and Smith’s index of salience of the free-list results. Results The local population depends primarily on slash-and-burn subsistence agriculture to meet their needs. Interviewees showed a strong empirical knowledge about the environmental problems of the river, and of their causes, consequences and potential solutions. Twenty-four tree species (dbh > 10 cm) were found at the reference sites. Tree density averaged 510 individuals per hectare (stdv = 91.6); and 12 species were considered the most abundant (density > 10ind/ha). There was a strong consensus among plant-specialists about the most important trees. The species lists from reference sites and plant-specialists presented an important convergence

  4. Dynamics of Greenhouse Gas Emissions from Riparian Buffer Zones and Wetlands as Hot Spots in Agricultural Landscapes

    International Nuclear Information System (INIS)

    The study considers various aspects of riparian buffer zones and wetlands for greenhouse gas emissions in agricultural landscapes of northern and north-eastern Europe. In particular, the impact of pulsing water regime, continuous loading and several alterations of environmental conditions on greenhouse gas emissions are taken into the consideration. In two case studies the isotopologue technique was used to distinguish between N2O sources in both riparian zones and constructed wetlands. Nitrous oxide (N2O) and nitrogen (N2) emissions, isotopic signatures of N2O and nitrate (NO3-) in groundwater of two differently loaded riparian grey alder stands in southern Estonia were investigated over a period of nine months. One area was a 38-year-old stand in Porijõgi (PJ), where uphill agricultural activities had been abandoned since the middle of 1990s, and the second area was a 55-year-old alder stand in Viiratsi (Vi), which still receives polluted lateral flow from uphill fields applied with pig slurry. Gas fluxes were measured in six sampling sessions, and water samples were analysed for NO3-, N2, N2O, and isotopic signatures of oxygen-18 (delta 18O, δ18O) and nitrogen-15 (delta 15N, δ15N) in N2O and NO3- in four of the six sessions. The N2O and N2 fluxes from both riparian zones did not differ significantly, being 9.6 ± 4.7 and 14.5 ± 3.9 μg N2O–N m−2 h−1, and 2 466 ± 275 and 3 083 ± 371 μg N2–N m−2 h−1 in PJ and Vi sites respectively, suggesting that gaseous N2 is the dominant gas emission from these alder stands. The isotopic signatures of N2O and NO3- were not significantly different between PJ and Vi study sites suggesting possible conversion of NO3- to N2O in both areas. The greater prevalence of N2 emissions over N2O in both areas, and the strong relationship between NO3- and N2O concentrations (r2 = 0.846, with p < 0.01) further suggested that denitrification is the main source of N2O and N2 fluxes in these grey alder stands. The dominant

  5. Modelling the water budget of a cultivated hillslope under Sudanian climate: evidenced role of the riparian forest

    Science.gov (United States)

    Richard, Aloïs; Galle, Sylvie; Descloitres, Marc; Cohard, Jean-Martial; Vandervaere, Jean-Pierre; Séguis, Luc

    2013-04-01

    Rainfall amounts in West African Sudanian region are important (700 - 1400 mm/year), but unevenly distributed all along the year, causing water scarcity and droughts during the dry season. To better manage the water resources, the aim of this study is to improve our understanding of hydrological processes at the hillslope scale in North Benin. This scale is retained because all hydrologic processes and their interactions are involved and can be documented: vadose zone and groundwater storages, rainfall, evapotranspiration and seepage fluxes. The study focuses on a typical cultivated hillslope of the upper Ouémé basin under Sudanian climate in North Benin. Crops are present on the main part of the hillslope and a riparian forest can be found at low elevation. At the basin scale, the riparian forests cover only a negligible fraction of the landscape but are commonly found, bordering the second and upper order streams. A vertical 2D approach is followed using the physically-based model HYDRUS-2D to simulate the hillslope hydrodynamics. A multi criteria approach is performed to evaluate the simulations using data from hydrological sensors deployed in the context of the AMMA-CATCH observing system (African Monsoon Multidisciplinary Analysis - Coupling the Tropical Atmosphere and the Hydrological Cycle). Since annual evapotranspiration can reach up to 83 % of the annual rainfall in this area, particular attention is paid to this term of the hydrologic cycle thanks to recent measurements of actual evapotranspiration (Large Aperture Scintillometer, Flux Tower). Hillslope hydrodynamics is correctly modelled in regard of soil moisture, deep groundwater level and actual evapotranspiration dynamics. A virtual experiment is performed at the hillslope scale removing the riparian forest and the deep groundwater table. This virtual experiment evidences these two roles of the riparian forest transpiration on the hillslope hydrodynamics: annual fluctuation of the deep groundwater

  6. The interactive effects of climate change, riparian management, and a non-native predators on stream-rearing salmon

    Science.gov (United States)

    Lawrence, David J.; Stewart-Koster, Ben; Olden, Julian D.; Ruesch, Aaron S.; Torgersen, Christian E.; Lawler, Joshua J.; Butcher, Don P.; Crown, Julia K.

    2014-01-01

    Predicting how climate change is likely to interact with myriad other stressors that threaten species of conservation concern is an essential challenge in aquatic ecosystems. This study provides a framework to accomplish this task in salmon-bearing streams of the northwestern United States, where land-use related reductions in riparian shading have caused changes in stream thermal regimes, and additional warming from projected climate change may result in significant losses of coldwater fish habitat over the next century. Predatory non-native smallmouth bass have also been introduced into many northwestern streams and their range is likely to expand as streams warm, presenting an additional challenge to the persistence of threatened Pacific salmon. The goal of this work was to forecast the interactive effects of climate change, riparian management, and non-native species on stream-rearing salmon, and to evaluate the capacity of restoration to mitigate these effects. We intersected downscaled global climate forecasts with a local-scale water temperature model to predict mid- and end-of-century temperatures in streams in the Columbia River basin; we compared one stream that is thermally impaired due to the loss of riparian vegetation and another that is cooler and has a largely intact riparian corridor. Using the forecasted stream temperatures in conjunction with fish-habitat models, we predicted how stream-rearing Chinook salmon and bass distributions would change as each stream warmed. In the highly modified stream, end-of-century warming may cause near total loss of Chinook salmon rearing habitat and a complete invasion of the upper watershed by bass. In the less modified stream, bass were thermally restricted from the upstream-most areas. In both systems, temperature increases resulted in higher predicted spatial overlap between stream-rearing Chinook salmon and potentially predatory bass in the early summer (2-4-fold increase) and greater abundance of bass. We

  7. Researches on Dynamical Succession Simulation of Typical Riparian Forests in Wenyu Watershed Upstream%文峪河流域上游典型河岸林动态演替模拟研究

    Institute of Scientific and Technical Information of China (English)

    郭玉永

    2012-01-01

    Dynamical succession of typical riparian forests and ecological footprint of species replacement were analyzed using the Markov model to research structure and function of existing communities in 33 typical riparian plots in Wenyu watershed upstream. Results showed that the change rate of pioneer species P. cathayana was the largest and it was quickly replaced by other species after improvement of lighting conditions and microclimate in the community succession process ; the quantity of B. albo-sinensis and B. platyphyUa were the largest during 40-80 year and quantity peak of Larix gmelinii appeared in 120-160 year while Picea asperata quantity was in growth condition with the time until 600 years ; the forest mainly consisted of Larix gmelinii and Picea asperata with the proportion of 50% respectively ; the riparian forest would develop to the climax community (spruce stands) after 600 years and plenty of realized communities in Wenyu watershed upstream were the pioneer and transitional period at 40-80 year scale. The study would be foundation for the mechanism of riparian dynamical succession and serve the ecosystem management of riparian forest buffer zone.%笔者通过在文峪河上游选取典型河岸林群落样地33块,采用Markov线性模型模拟预测河岸林群落的动态演替过程,分析群落乔木物种替代的轨迹变化,阐明现实林分组成的结构和功能特性。研究结果表明:1)在演替过程中,以先锋树种青杨的变化速率最大,在完成林地光照条件及小气候的改善后,迅速被其它树种排挤。2)红桦和白桦在40a-80a间林分数量达到最高点;落叶松林分数量最高点出现在120a-160a间,以后几百年逐步退化减少。云杉林分数量随时间延长处于增长状态,在600a内未达到生长顶峰。3)落叶松和云杉林二者数量在230a左右时约为10株,林分以落叶松和云杉林为主,比例各占50%.4)文峪河上游大部分河

  8. Interactions among riparian vegetation, flow and sediment in a sand bed river: Implications for restoration

    Science.gov (United States)

    Gorrick, S.; Rodriguez, J. F.

    2012-12-01

    We present a set of laboratory experiments based on field site conditions on a sand bed stream in Australia that is currently being restored by reintroduction of lost riparian vegetation. Three experiments were conducted in order to investigate both the local and reach-scale impacts of bank vegetation on flow and sediment dynamics. The first experiment contained no bank vegetation and was similar to the original state of the stream. The second experiment placed a series of three inline vegetation patches along the outer bank, simulating the design of the ongoing restoration works. The third experiment used a continuous strip of vegetation along the outer bank, which represents a more traditional restoration technique. In each experiment flow and sediment measurements were carried out, including ADV velocities, water surface elevations, suspended and bedload sediment transport rates and bed evolution. The analysis focussed on the quantification of flow and sediment fluxes and the resulting stream morphology, which responded to the presence of vegetation and to changes in stream curvature and width. Both arrangements of vegetation provided effective bank protection; however the patches used less vegetation and were thus more efficient. The reach-scale effects included changes to stream curvature, stream width and redistribution of sediments, all of which have important implications for management. Recommendations also include the selection of optimum patch size and spacing as well as plant composition.

  9. White poplar (Populus alba) as a biomonitor of trace elements in contaminated riparian forests

    International Nuclear Information System (INIS)

    Trees can be used to monitor the level of pollution of trace elements in the soil and atmosphere. In this paper, we surveyed the content of eight trace elements (As, Cd, Cu, Fe, Mn, Ni, Pb and Zn) in leaves and stems of white poplar (Populus alba) trees. We selected 25 trees in the riparian forest of the Guadiamar River (S. Spain), one year after this area was contaminated by a mine spill, and 10 trees in non-affected sites. The spill-affected soils had significantly higher levels of available cadmium (mean of 1.25 mg kg-1), zinc (117 mg kg-1), lead (63.3 mg kg-1), copper (58.0 mg kg-1) and arsenic (1.70 mg kg-1), than non-affected sites. The concentration of trace element in poplar leaves was positively and significantly correlated with the soil availability for cadmium and zinc, and to a lesser extent for arsenic (log-log relationship). Thus, poplar leaves could be used as biomonitors for soil pollution of Cd and Zn, and moderately for As

  10. Carbon dioxide and methane fluxes: Seasonal dynamics from inland riparian ecosystems, northeast China

    International Nuclear Information System (INIS)

    Riparian wetland ecosystems have been described as significant hotspots for carbon dioxide (CO2) and methane (CH4) fluxes, but their role in the release and sequestration of these greenhouse gases has been insufficiently assessed within China. The influences of vegetation and soil parameters on daily and seasonal variations in carbon flux in the Nenjiang basin, northeast China, were recorded using a static closed-chamber technique during the non-growing (November and January) and growing (June, July and August) seasons of 2009–2010. Seasonal differences in average CO2 flux were observed (growing season: 6.605 g·C·m−2 h−1; non-growing season: − 0.185 g·C·m−2 h−1) and these were significantly correlated with CH4 emission (r = 0.532, p = 0.011) and soil temperature at 5 cm depth below ground (r = 0.852, p = 0.000). Average diel gaseous flux showed significant variation between hours for both gases (CO2 flux one-way ANOVA F = 3.075, p 4 flux one way ANOVA F = 2.622, p 4 and CO2 fluxes and multiple vegetation and soil parameters. For example at both sites, growing season-CH4 flux was correlated with vegetation cover (r = 0.580, p 2 was significantly correlated with CH4 emission and soil temperature. ► Growing season-CH4 flux was significantly correlated with vegetation cover, total vegetation phosphorous and soil nitrogen

  11. Analysis of carbon and nitrogen dynamics in riparian soils: model validation and sensitivity to environmental controls.

    Science.gov (United States)

    Batlle-Aguilar, J; Brovelli, A; Luster, J; Shrestha, J; Niklaus, P A; Barry, D A

    2012-07-01

    The Riparian Soil Model (RSM) of Brovelli et al. (2012) was applied to study soil nutrient turnover in a revitalized section of the Thur River, North-East Switzerland. In the present work, the model was calibrated on field experimental data, and satisfactorily reproduced soil respiration, organic matter stocks and inorganic nitrogen fluxes. Calibrated rates were in good agreement with the ranges reported in the literature. The main discrepancies between model and observations were for dissolved organic carbon. The sensitivity of the model to environmental factors was also analyzed. Soil temperature was the most influential factor at daily and seasonal scales while effects of soil moisture were weak overall. The ecosystem sensitivity to temperature changes was quantified using the Q10 index. The seasonal behavior observed was related to the influence of other forcing factors and to the different state (density and activity) of the microbial biomass pool during the year. Environmental factors influencing microbial decomposition, such as the C:N ratio and litter input rate, showed intermediate sensitivity. Since these parameters are tightly linked to the vegetation type, the analysis highlighted the effect of the aboveground ecosystem on soil functioning. PMID:22578524

  12. Phosphorus concentrations in soil and subsurface water: a field study among cropland and riparian buffers.

    Science.gov (United States)

    Young, Eric O; Briggs, Russell D

    2008-01-01

    Riparian buffers can be effective at removing phosphorus (P) in overland flow, but their influence on subsurface P loading is not well known. Phosphorus concentrations in the soil, soil solution, and shallow ground water of 16 paired cropland-buffer plots were characterized during 2004 and 2005. The sites were located at two private dairy farms in Central New York on silt and gravelly silt loams (Aeric Endoaqualfs, Fluvaquentic Endoaquepts, Fluvaquentic Eutrudepts, Glossaquic Hapludalfs, and Glossic Hapludalfs). It was hypothesized that P availability (sodium acetate extractable-P) and soil-landscape variability would affect P release to the soil solution and shallow ground water. Results showed that P availability tended to be greater in crop fields relative to paired buffer plots. Soil P was a good indicator of soil solution dissolved ( or =0.45 microm) reactive P (PRP), and dissolved unreactive P (DUP) concentrations in ground water. Soil organic matter and 50-cm depth soil solution DRP in buffers jointly explained 75% of the average buffer ground water DRP variability. Results suggest that buffers were relatively effective at reducing soil solution and shallow ground water DRP concentrations, but their impact on particulate and organic P in ground water was less clear. PMID:18178879

  13. Effects of watershed and riparian zone characteristics on nutrient concentrations in the River Scheldt Basin

    Directory of Open Access Journals (Sweden)

    J. Meynendonckx

    2006-05-01

    Full Text Available The relative influence of a set of watershed characteristics on surface water nutrient concentrations was examined in 173 watersheds within two subcatchments (Upper-Scheldt and Nete of the River Scheldt Basin (Flanders, Belgium. Each watershed was described by seasonal rainfall, discharge loading of point sources, morphological characteristics (area, average slope, drainage density, elongation, land use and soil properties (soil texture and drainage. Partial regression analysis revealed that soil drainage variables had the strongest influence on nutrient concentrations. Additional influence was exerted by land use and point source loading variables. Nitrate concentrations were positively correlated with effluent loadings coming from wastewater treatment plants and with the area of agricultural land. Phosphate concentrations were best explained by effluent loadings of industrial point sources and by the area of urban land. Land use close to the river was not a better predictor of nitrate and phosphate concentrations than land use away from the river. This suggests that the mediating impact of riparian zones is rather explained by the hydrologic pathways within the buffer strip.

  14. Variations in Soil Salinity and Riparian Vegetation Coverage as Indicators of Stress in an Arid Watershed

    Science.gov (United States)

    Gutierrez, M.; Mickus, K.; Johnson, E.

    2003-12-01

    Soil salinity and riparian vegetation coverages of an arid area in northern Mexico through time were investigated. The study area comprises a 10 km segment of the lower Rio Conchos and surrounding undeveloped, non-irrigated land. The amount of area affected by salinity and the type of salinity were determined using EC (electrical conductivity) in conjunction with satellite images and corroborated by field analysis. The soil salinity derived from the remote sensing data was tied to precipitation, greenness of vegetation and water level of a nearby reservoir. The most appropriate method to assess soil salinity was found to be the selective principal component (SPCA) technique of Chavez and Kwarteng while the techniques utilized to discriminate vigorously-growing vegetation were tasseled cap transformation and the normalized difference vegetation index (NDVI). With this region undergoing a severe drought for the last ten years, the response of different parts of the ecosystem and changes in vegetation that so closely affect wildlife and other natural resources in this area can be better evaluated.

  15. Isolation and Characterization of Four Gram-PositiveNickel-Tolerant Microorganisms from Contaminated Riparian Sediments

    Energy Technology Data Exchange (ETDEWEB)

    Van Nostrand, Joy D.; Khijniak, Tatiana V.; Gentry, Terry J.; Novak, Michelle T.; Sowder, Andrew G.; Zhou, Jizhong Z.; Bertsch, PaulM.; Morris, Pamela J.

    2006-08-30

    Microbial communities from riparian sediments contaminatedwith high levels of Ni and U were examined for metal-tolerantmicroorganisms. Isolation of four aerobic Ni-tolerant, Gram-positiveheterotrophic bacteria indicated selection pressure from Ni. Theseisolates were identified as Arthrobacter oxydans NR-1, Streptomycesgalbus NR-2, Streptomyces aureofaciens NR-3, and Kitasatosporacystarginea NR-4 based on partial 16S rDNA sequences. A functional genemicroarray containing gene probes for functions associated withbiogeochemical cycling, metal homeostasis, and organic contaminantdegradation showed little overlap among the four isolates. Fifteen of thegenes were detected in all four isolates with only two of these relatedto metal resistance, specifically to tellurium. Each of the four isolatesalso displayed resistance to at least one of six antibiotics tested, withresistance to kanamycin, gentamycin, and ciprofloxacin observed in atleast two of the isolates. Further characterization of S. aureofaciensNR-3 and K. cystarginea NR-4 demonstrated that both isolates expressed Nitolerance constitutively. In addition, both were able to grow in higherconcentrations of Ni at pH 6 as compared to pH 7 (42.6 and 8.5 mM Ni atpH 6 and 7, respectively). Tolerance to Cd, Co, and Zn was also examinedin these two isolates; a similar pH-dependent metal tolerance wasobserved when grown with Co and Zn. Neither isolate was tolerant to Cd.These findings suggest that Ni is exerting a selection pressure at thissite for metal-resistant actinomycetes.

  16. Snowmelt induced hydrologic perturbations drive dynamic microbiological and geochemical behaviors across a shallow riparian aquifer

    Science.gov (United States)

    Danczak, Robert; Yabusaki, Steven; Williams, Kenneth; Fang, Yilin; Hobson, Chad; Wilkins, Michael

    2016-05-01

    Shallow riparian aquifers represent hotspots of biogeochemical activity in the arid western US. While these environments provide extensive ecosystem services, little is known of how natural environmental perturbations influence subsurface microbial communities and associated biogeochemical processes. Over a six-month period we tracked the annual snowmelt-driven incursion of groundwater into the vadose zone of an aquifer adjacent to the Colorado River, leading to increased dissolved oxygen (DO) concentrations in the normally suboxic saturated zone. Strong biogeochemical heterogeneity was measured across the site, with abiotic reactions between DO and sulfide minerals driving rapid DO consumption and mobilization of redox active species in reduced aquifer regions. Conversely, extensive DO increases were detected in less reduced sediments. 16S rRNA gene surveys tracked microbial community composition within the aquifer, revealing strong correlations between increases in putative oxygen-utilizing chemolithoautotrophs and heterotrophs and rising DO concentrations. The gradual return to suboxic aquifer conditions favored increasing abundances of 16S rRNA sequences matching members of the Microgenomates (OP11) and Parcubacteria (OD1) that have been strongly implicated in fermentative processes. Microbial community stability measurements indicated that deeper aquifer locations were relatively less affected by geochemical perturbations, while communities in shallower locations exhibited the greatest change. Reactive transport modeling of the geochemical and microbiological results supported field observations, suggesting that a predictive framework can be applied to develop a greater understanding of such environments.

  17. Microbial communities in riparian soils of a settling pond for mine drainage treatment.

    Science.gov (United States)

    Fan, Miaochun; Lin, Yanbing; Huo, Haibo; Liu, Yang; Zhao, Liang; Wang, Entao; Chen, Weimin; Wei, Gehong

    2016-06-01

    Mine drainage leads to serious contamination of soil. To assess the effects of mine drainage on microbial communities in riparian soils, we used an Illumina MiSeq platform to explore the soil microbial composition and diversity along a settling pond used for mine drainage treatment. Non-metric multidimensional scaling analysis showed that the microbial communities differed significantly among the four sampling zones (influent, upstream, downstream and effluent), but not seasonally. Constrained analysis of principal coordinates indicated heavy metals (zinc, lead and copper), total sulphur, pH and available potassium significantly influenced the microbial community compositions. Heavy metals were the key determinants separating the influent zone from the other three zones. Lower diversity indices were observed in the influent zone. However, more potential indicator species, related to sulphur and organic matter metabolism were found there, such as the sulphur-oxidizing genera Acidiferrobacter, Thermithiobacillus, Limnobacter, Thioprofundum and Thiovirga, and the sulphur-reducing genera Desulfotomaculum and Desulfobulbus; the organic matter degrading genera, Porphyrobacter and Paucimonas, were also identified. The results indicated that more microorganisms related to sulphur- and carbon-cycles may exist in soils heavily contaminated by mine drainage. PMID:27055175

  18. Characterization of methane, benzene and toluene-oxidizing consortia enriched from landfill and riparian wetland soils.

    Science.gov (United States)

    Lee, Eun-Hee; Park, Hyunjung; Cho, Kyung-Suk

    2010-12-15

    The microbial oxidations of methane (M) and volatile organic compounds (VOCs) were compared with those of M and VOCs alone after enriching soil samples with M and/or VOCs. Landfill cover and riparian wetland soils from which M and VOCs were simultaneously emitted were selected as representative samples. Benzene (B) and toluene (T) were employed as the model VOCs. With the landfill soil consortia, the rate of M oxidation decreased from 4.15-5.56 to 2.26-3.42 μmol g-dry soil(-1)h(-1) in the presence of both B and T, but with the wetland soil consortia the rate of M oxidation (3.09 μmol g-dry soil(-1)h(-1)) in the mixture of M as well as both B and T was similar to that of M alone (3.04 μmol g-dry soil(-1)h(-1)). Compared with the methanotrophic community with M alone, the portion of type II methanotrophs was greater in the landfill consortia; whereas, the proportion in wetland consortia was less in the presence of both B and T. The oxidations of B and T were stimulated by the presence of M with both the landfill and wetland consortia. There were no correlations between the oxidation rate of M and those of B and T with the gene copy numbers of pmoA and tmoA responsible for the oxidations. PMID:20832163

  19. Configuration of water resources for a typical river basin in an arid region of China based on the ecological water requirements (EWRs) of desert riparian vegetation

    Science.gov (United States)

    Ling, Hongbo; Guo, Bin; Xu, Hailiang; Fu, Jinyi

    2014-11-01

    Desert riparian vegetation is a natural cover promoting the stability and development of inland river ecosystems in arid regions. Calculating the ecological water requirements (EWRs) of desert riparian vegetation is an important step in achieving reasonable water utilization. Therefore, this study examined the Tarim River, located in an extremely arid region of China, and collected relevant data on hydrology, weather and vegetation using remote sensing. Subsequently, we analyzed the spatial distribution of the desert riparian vegetation in four sections of the Tarim River and calculated the EWR of the desert riparian vegetation using the phreatic evaporation model; additionally, we determined the required runoffs at five hydrologic stations based on the water balance principle. Ultimately, the necessary protection ranges and goals for desert riparian vegetation were established according to the water resource variations in the Tarim River. Our research showed that the total area of desert riparian vegetation along the Tarim River is 16,285.3 km2; this distribution area gradually decreased as the distance from the river increased, and areas varied in the different river sections. The EWRs of desert riparian vegetation from Sections 1 to 5 are 5.698 × 108, 7.585 × 108, 4.900 × 108, 4.101 × 108 m3 and 1.078 × 108 m3, respectively. Therefore, the total EWR of the study region is 23.362 × 108 m3. In terms of the transpiration law of the "unimodal type", the peak value of EWR of natural vegetation occurs in July, and the decreasing trend appears in the other months. Based on the water balance principle, the required runoffs in Alar, Xinquman, Yingbaza, Wusiman and Qiala were determined to be 47.105 × 108, 35.174 × 108, 22.734 × 108, 15.775 × 108 and 7.707 × 108 m3, respectively. According to the water resource frequency and the EWR of the desert riparian vegetation along the Tarim River, we divided the region into three protection ranges: key protection (8

  20. Disturbance regimes and gaps characteristics of the desert riparian forest at the middle reaches of Tarim River%塔里木荒漠河岸林干扰状况与林隙特征

    Institute of Scientific and Technical Information of China (English)

    韩路; 王海珍; 陈加利; 于军

    2011-01-01

    majority of gaps consisted of 2 to 5 gap makers with the 4 gap makers category being the most abundant group and the average number of gap makers was 4. I per gap. The diameter at breast height ( DBH) of most gap makers ranged from 5 to 25cm, and their height varied from 4 to 8m. The average area of EG and CG formed by each gap maker was 27. 12m2 and 11. 32m2 , respectively. The structure of DBH classes of the gap border trees ( GBT) show a normal distribution, but tree height classes show a left-skewed distribution. The average numbers of GBTs was 8. 375 per gap. The average DBH of' GBT was 73. 1% higher than that of' gap makers, indicating the gap disturbance was a frequent occurrence in the desert riparian forest, and the continuously declining level of underground water was the driving force of gap formation.