Sample records for sunglint rivers vegetation

  1. River Plumes in Sunglint, Sarawak, Borneo (United States)


    The sunglint pattern along the coast of Sarawak (3.0N, 111.5E) delineates the boundry of fresh water river plumes as they flow into the South China Sea. The fresh water lens (boundry between fresh and sea water) overides the saline and more dense sea water and oils, both natural and man made, collect along the convergence zones and dampen wave action. As a result, the smoother sea surface appears bright in the sunglint pattern.

  2. Role of vegetation on river bank accretion

    NARCIS (Netherlands)

    Vargas Luna, A.


    There is rising awareness of the need to include the effects of vegetation in studies dealing with the morphological response of rivers. Vegetation growth on river banks and floodplains alters the river bed topography, reduces the bank erosion rates and enhances the development of new floodplains

  3. Bonneville - Hood River Vegetation Management Environmental Assessment

    Energy Technology Data Exchange (ETDEWEB)



    To maintain the reliability of its electrical system, BPA, in cooperation with the U.S. Forest Service, needs to expand the range of vegetation management options used to clear unwanted vegetation on about 20 miles of BPA transmission line right-of-way between Bonneville Dam and Hood River; Oregon, within the Columbia Gorge National Scenic Area (NSA). We propose to continue controlling undesirable vegetation using a program of Integrated Vegetation Management (IVM) which includes manual, biological and chemical treatment methods. BPA has prepared an Environmental Assessment (EA) (DOE/EA-1257) evaluating the proposed project. Based on the analysis in the EA, BPA has determined that the proposed action is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement (EIS) is not required and BPA is issuing this FONSI.

  4. Information Content of Aerosol Retrievals in the Sunglint Region (United States)

    Ottaviani, M.; Knobelspiesse, K.; Cairns, B.; Mishchenko, M.


    We exploit quantitative metrics to investigate the information content in retrievals of atmospheric aerosol parameters (with a focus on single-scattering albedo), contained in multi-angle and multi-spectral measurements with sufficient dynamical range in the sunglint region. The simulations are performed for two classes of maritime aerosols with optical and microphysical properties compiled from measurements of the Aerosol Robotic Network. The information content is assessed using the inverse formalism and is compared to that deriving from observations not affected by sunglint. We find that there indeed is additional information in measurements containing sunglint, not just for single-scattering albedo, but also for aerosol optical thickness and the complex refractive index of the fine aerosol size mode, although the amount of additional information varies with aerosol type.

  5. Spatial heterogeneity study of vegetation coverage at Heihe River Basin (United States)

    Wu, Lijuan; Zhong, Bo; Guo, Liyu; Zhao, Xiangwei


    Spatial heterogeneity of the animal-landscape system has three major components: heterogeneity of resource distributions in the physical environment, heterogeneity of plant tissue chemistry, heterogeneity of movement modes by the animal. Furthermore, all three different types of heterogeneity interact each other and can either reinforce or offset one another, thereby affecting system stability and dynamics. In previous studies, the study areas are investigated by field sampling, which costs a large amount of manpower. In addition, uncertain in sampling affects the quality of field data, which leads to unsatisfactory results during the entire study. In this study, remote sensing data is used to guide the sampling for research on heterogeneity of vegetation coverage to avoid errors caused by randomness of field sampling. Semi-variance and fractal dimension analysis are used to analyze the spatial heterogeneity of vegetation coverage at Heihe River Basin. The spherical model with nugget is used to fit the semivariogram of vegetation coverage. Based on the experiment above, it is found, (1)there is a strong correlation between vegetation coverage and distance of vegetation populations within the range of 0-28051.3188m at Heihe River Basin, but the correlation loses suddenly when the distance greater than 28051.3188m. (2)The degree of spatial heterogeneity of vegetation coverage at Heihe River Basin is medium. (3)Spatial distribution variability of vegetation occurs mainly on small scales. (4)The degree of spatial autocorrelation is 72.29% between 25% and 75%, which means that spatial correlation of vegetation coverage at Heihe River Basin is medium high.

  6. River ecosystem response to prescribed vegetation burning on Blanket Peatland. (United States)

    Brown, Lee E; Johnston, Kerrylyn; Palmer, Sheila M; Aspray, Katie L; Holden, Joseph


    Catchment-scale land-use change is recognised as a major threat to aquatic biodiversity and ecosystem functioning globally. In the UK uplands rotational vegetation burning is practised widely to boost production of recreational game birds, and while some recent studies have suggested burning can alter river water quality there has been minimal attention paid to effects on aquatic biota. We studied ten rivers across the north of England between March 2010 and October 2011, five of which drained burned catchments and five from unburned catchments. There were significant effects of burning, season and their interaction on river macroinvertebrate communities, with rivers draining burned catchments having significantly lower taxonomic richness and Simpson's diversity. ANOSIM revealed a significant effect of burning on macroinvertebrate community composition, with typically reduced Ephemeroptera abundance and diversity and greater abundance of Chironomidae and Nemouridae. Grazer and collector-gatherer feeding groups were also significantly less abundant in rivers draining burned catchments. These biotic changes were associated with lower pH and higher Si, Mn, Fe and Al in burned systems. Vegetation burning on peatland therefore has effects beyond the terrestrial part of the system where the management intervention is being practiced. Similar responses of river macroinvertebrate communities have been observed in peatlands disturbed by forestry activity across northern Europe. Finally we found river ecosystem changes similar to those observed in studies of wild and prescribed forest fires across North America and South Africa, illustrating some potentially generic effects of fire on aquatic ecosystems.

  7. Prediction of the Sun-Glint Locations for the Communication, Ocean and Meteorological Satellite

    Directory of Open Access Journals (Sweden)

    Jae-Ik Park


    Full Text Available For the Communication, Ocean and Meteorological Satellite (COMS which will be launched in 2008, an algorithm for finding the precise location of the sun-glint point on the ocean surface is studied. The precise locations of the sun-glint are estimated by considering azimuth and elevation angles of Sun-satellite-Earth geometric position and the law of reflection. The obtained nonlinear equations are solved by using the Newton-Raphson method. As a result, when COMS is located at 116.2°E or 128.2°E longitude, the sun-glint covers region of ±10° (N-S latitude and 80-150° (E-W longitude. The diurnal path of the sun-glint in the southern hemisphere is curved towards the North Pole, and the path in the northern hemisphere is forwards the south pole. The algorithm presented in this paper can be applied to predict the precise location of sun-glint region in any other geostationary satellites.

  8. River flow response to changes in vegetation cover in a South ...

    African Journals Online (AJOL)

    It was hypothesised in this study that annual river yield (river flow as a fraction of rainfall) in the Molenaars catchment near Paarl, South Africa co-varies with an index of green vegetation cover derived from satellite data (the normalised difference vegetation index, NDVI). The catchment was partitioned into 'upland' and ...

  9. Forty years of vegetation change on the Missouri River floodplain (United States)

    Johnson, W. Carter; Dixon, Mark D.; Scott, Michael L.; Rabbe, Lisa; Larson, Gary; Volke, Malia; Werner, Brett


    Comparative inventories in 1969 and 1970 and in 2008 of vegetation from 30 forest stands downstream of Garrison Dam on the Missouri River in central North Dakota showed (a) a sharp decline in Cottonwood regeneration; (b) a strong compositional shift toward dominance by green ash; and (c) large increases in invasive understory species, such as smooth brome, reed canary grass, and Canada thistle. These changes, and others discovered during remeasurement, have been caused by a complex of factors, some related to damming (altered hydrologic and sediment regimes, delta formation, and associated wet-dry cycles) and some not (diseases and expansion of invasive plants). Dominance of green ash, however, may be short lived, given the likelihood that the emerald ash borer will arrive in the Dakotas in 5-10 years, with potentially devastating effects. The prospects for recovery of this valuable ecosystem, rich in ecosystem goods and services and in American history, are daunting.

  10. An ecological study of the vegetation in three former river beds

    NARCIS (Netherlands)

    Donselaar-Ten Bokkel Huinink, van W.A.E.


    In three former river beds of the river Waal near Zaltbommel a study was made of the factors which determine the differentiation in the vegetation. The water in each of the three beds is eutrophic. One of the beds is situated inside the main dike of the present river, the two other ones outside the

  11. Macrophytic flora and vegetation of the rivers Svrljiški and Beli Timok (Eastern Serbia

    Directory of Open Access Journals (Sweden)

    Jenačković, D.


    Full Text Available Floristic and phytocoenological investigations of macrophytic vegetation of the rivers Svrljiški and Beli Timok in Eastern Serbia were performed. Analysis of the collected plants showed that the hydrophilous flora contains 26 species from 17 families and 21 genuses. Phytocoenological analysis showed 5 different associations from 3 alliances, 3 orders and 3 classis. Aquatic vegetation is represented by the associations Myriophyllo-Potametum and Potametum nodosi, moor vegetation by associations Scirpetum lacustris and Sparganietum erecti, while nitrophilous vegetation is represented by association Polygono-Bidentetum tripartitae. These associations have formed three clear vegetation belts: submerged, floating and emerged vegetation.

  12. Geomorphic and vegetation changes in a meandering dryland river regulated by a large dam, Sauce Grande River, Argentina (United States)

    Casado, Ana; Peiry, Jean-Luc; Campo, Alicia M.


    This paper investigates post-dam geomorphic and vegetation changes in the Sauce Grande River, a meandering dryland river impounded by a large water-conservation dam. As the dam impounds a river section with scarce influence of tributaries, sources for fresh water and sediment downstream are limited. Changes were inspected based on (i) analysis of historical photographs/imagery spanning pre- (1961) and post-dam (1981, 2004) channel conditions for two river segments located above and below the dam, and (ii) field survey of present channel conditions for a set of eight reference reaches along the river segments. Whilst the unregulated river exhibited active lateral migration with consequent adjustments of the channel shape and size, the river section below the dam was characterized by (i) marked planform stability (93 to 97%), and by (ii) vegetation encroachment leading to alternating yet localized contraction of the channel width (up to 30%). The present river displays a moribund, stable channel where (i) redistribution of sediment along the river course no longer occurs and (ii) channel forms constitute a remnant of a fluvial environment created before closing the dam, under conditions of higher energy. In addition to providing new information on the complex geomorphic response of dryland rivers to impoundment, this paper represents the very first geomorphic assessment of the regulated Sauce Grande and therefore provides an important platform to underpin further research assessing the geomorphic state of this highly regulated dryland river.

  13. A Check-list of Some Elements of the Vegetation in three river ...

    African Journals Online (AJOL)

    The composition of some elements of the aquatic flora was determined in three river basins namely Ayensu, Birim and Densu, in the Okyeman area in Southern Ghana. Samples of these vegetation types, namely bryophytes, podostemonads and rhodophytes, in the three river basins were taken at 16 sites as follows: 4 ...

  14. Concentrations of metals in river sediment and wetland vegetations ...

    African Journals Online (AJOL)

    Levels of metals were determined in river sediment, rice and sugarcane juice from Lake Victoria basin where small-scale gold processing activities are carried out to assess levels of contamination. Concentrations of metals in river sediments were generally high in areas that were closest to gold ore processing sites.

  15. Mechanisms of vegetation removal by floods on bars of a heavily managed gravel bed river (The Isere River, France) (United States)

    Jourdain, Camille; Belleudy, Philippe; Tal, Michal; Malavoi, Jean-René


    In natural alpine gravel bed rivers, floods and their associated bedload transport maintain channels active and free of mature woody vegetation. In managed rivers, where flood regime and sediment supply have been modified by hydroelectric infrastructures and sediment mining, river beds tend to stabilize. As a result, in the recent past, mature vegetation has established on gravel bars of many gravel bed rivers worldwide. This established vegetation increases the risk of flooding by decreasing flow velocity and increasing water levels. In addition, the associated reduction in availability of pioneer habitats characteristic of these environments typically degrades biodiversity. Managing hydrology in a way that would limit vegetation establishment on bars presents an interesting management option. In this context, our study aims at understanding the impacts of floods of varying magnitude on vegetation removal, and identifying and quantifying the underlying mechanisms. Our study site is the Isère River, a heavily managed gravel bed river flowing in the western part of the French Alps. We studied the impact of floods on sediment transport and vegetation survival at the bar scale through field monitoring from 2014 to 2015, focusing on young salicaceous vegetation (chains, and topographic surveys. Hourly water discharge was obtained from the national gauging network. The hydraulics of monitored floods was characterized using a combination of field measurements and 2D hydraulic modeling: water levels were measured with pressure sensors and Large Scale Particle Velocimetry was used to measure flow velocities. These data were used to calibrate 2D hydrodynamic model using TELEMAC2D. At the reach scale, removal of mature vegetation was assed using a series of historical aerial photographs between 2001 and 2015. Our monitoring period covered a series of floods with recurrence intervals of 2 to 4 times per year, as well as one large flood with a 10 year return period. Only the

  16. Evaluating the impact of a wide range of vegetation densities on river channel pattern (United States)

    Pattison, Ian; Roucou, Ron


    Braided rivers are very dynamic systems which have complex controls over their planform and flow dynamics. Vegetation is one variable which influences channel geometry and pattern, through its effect on local flow hydraulics and the process continuum of sediment erosion-transport-deposition. Furthermore, where in the braided floodplain stable vegetation develops depends on the temporal sequencing of the river discharge i.e. floods. Understanding the effect of vegetation in these highly dynamic systems has multiple consequences for human activity and floodplain management. This paper focusses on the specific role of vegetation density in controlling braided river form and processes. Previous research in this field has been contradictory; with Gran and Paola (2001) finding that increasing vegetation density decreased the number of active channels. In contrast, Coulthard (2005] observed that as vegetation become denser there was an increase in the number of channels. This was hypothesized to be caused by flow separation around vegetation and the development of bars immediately downstream of the plant. This paper reports the results from a set of experiments in a 4m by 1m flume, where discharge, slope and sediment size were kept constant. Artificial grass was used to represent vegetation with a density ranging from 50 plants/m2 to 400 plants/m2. Digital photographs, using a GoPro camera with a fish eye lens, were taken from ~1m above the flume at an interval of 30 seconds during the 3 hour experiment. The experiments showed that as the vegetation density increased from 50 to 150 plants/m2, the number of channel bars developing doubled from 12 to 24. At vegetation densities greater than 150 plants/m2 there was a decline in the number of bars created to a minimum of 8 bars for a density of 400 plants/m2. We attribute these patterns to the effect that the vegetation has on flow hydraulics, sediment transport processes and the spatial patterns of erosion and deposition. We

  17. Effects of river ice on bank morphology and riparian vegetation along Peace River, Clayhurst to Fort Vermilion

    International Nuclear Information System (INIS)

    Uunila, L.S.


    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

  18. The Irrigation Effect: How River Regulation Can Promote Some Riparian Vegetation (United States)

    Gill, Karen M.; Goater, Lori A.; Braatne, Jeffrey H.; Rood, Stewart B.


    River regulation impacts riparian ecosystems by altering the hydrogeomorphic conditions that support streamside vegetation. Obligate riparian plants are often negatively impacted since they are ecological specialists with particular instream flow requirements. Conversely, facultative riparian plants are generalists and may be less vulnerable to river regulation, and could benefit from augmented flows that reduce drought stress during hot and dry periods. To consider this `irrigation effect' we studied the facultative shrub, netleaf hackberry ( Celtis reticulata), the predominant riparian plant along the Hells Canyon corridor of the Snake River, Idaho, USA, where dams produce hydropeaking, diurnal flow variation. Inventories of 235 cross-sectional transects revealed that hackberry was uncommon upstream from the reservoirs, sparse along the reservoir with seasonal draw-down and common along two reservoirs with stabilized water levels. Along the Snake River downstream, hackberry occurred in fairly continuous, dense bands along the high water line. In contrast, hackberry was sparsely scattered along the free-flowing Salmon River, where sandbar willow ( Salix exigua), an obligate riparian shrub, was abundant. Below the confluence of the Snake and Salmon rivers, the abundance and distribution of hackberry were intermediate between the two upstream reaches. Thus, river regulation apparently benefited hackberry along the Snake River through Hells Canyon, probably due to diurnal pulsing that wets the riparian margin. We predict similar benefits for some other facultative riparian plants along other regulated rivers with hydropeaking during warm and dry intervals. To analyze the ecological impacts of hydropeaking we recommend assessing daily maxima, as well as daily mean river flows.

  19. Bank vegetation of Rimavica River from the perspective of landscape ecology

    International Nuclear Information System (INIS)

    Aschenbrenner, S.


    The object of our study was 5.3 km long stretch of the river Rimavica with its adjacent ecosystems. The research results show that most of the observed vegetation fulfill its function well in the country. Only certain sections require more human care, in order to strengthen their positive impact on the flow of water and other components of the ecosystem. (authors)


    We evaluated the importance of alien species in existing vegetation along wadeable streams of a large, topographically diverse river basin in eastern Oregon, USA; sampling 165 plots (30 × 30 m) across 29 randomly selected 1-km stream reaches. Plots represented eight streamside co...

  1. Effect of river flow fluctuations on riparian vegetation dynamics: Processes and models (United States)

    Vesipa, Riccardo; Camporeale, Carlo; Ridolfi, Luca


    Several decades of field observations, laboratory experiments and mathematical modelings have demonstrated that the riparian environment is a disturbance-driven ecosystem, and that the main source of disturbance is river flow fluctuations. The focus of the present work has been on the key role that flow fluctuations play in determining the abundance, zonation and species composition of patches of riparian vegetation. To this aim, the scientific literature on the subject, over the last 20 years, has been reviewed. First, the most relevant ecological, morphological and chemical mechanisms induced by river flow fluctuations are described from a process-based perspective. The role of flow variability is discussed for the processes that affect the recruitment of vegetation, the vegetation during its adult life, and the morphological and nutrient dynamics occurring in the riparian habitat. Particular emphasis has been given to studies that were aimed at quantifying the effect of these processes on vegetation, and at linking them to the statistical characteristics of the river hydrology. Second, the advances made, from a modeling point of view, have been considered and discussed. The main models that have been developed to describe the dynamics of riparian vegetation have been presented. Different modeling approaches have been compared, and the corresponding advantages and drawbacks have been pointed out. Finally, attention has been paid to identifying the processes considered by the models, and these processes have been compared with those that have actually been observed or measured in field/laboratory studies.

  2. The influence of flood frequency, riparian vegetation and threshold on long-term river transport capacity (United States)

    Croissant, Thomas; Lague, Dimitri; Davy, Philippe


    Climate fluctuations at geological timescales control the capacity of rivers to transport sediment with consequences on geochemical cycles, sedimentary basins dynamics and sedimentation/tectonics interactions. While the impact of differential friction generated by riparian vegetation has been studied for individual flood events, its impact on the long-term sediment transport capacity of rivers, modulated by the frequency of floods remains unknown. Here, we investigate this effect on a simplified river-floodplain configuration obeying observed hydraulic scaling laws. We numerically integrate the full-frequency magnitude distribution of discharge events and its impact on the transport capacity of bedload and suspended material for various level of vegetation-linked differential friction. We demonstrate that riparian vegetation by acting as a virtual confinement of the flow i) increases significantly the instantaneous transport capacity of the river independently of the transport mode and ii) increases the long term bedload transport rates as a function of discharge variability. Our results expose the dominance of flood frequency rather than riparian vegetation on the long term sediment transport capacity. Therefore, flood frequency has to be considered when evaluating long-term bedload transport capacity while floodplain vegetation is important only in high discharge variability regimes. By comparing the transport capacity of unconfined alluvial rivers and confined bedrock gorges, we demonstrate that the latter always presents the highest long term transport capacity at equivalent width and slope. The loss of confinement at the transition between bedrock and alluvial river must be compensated by a widening or a steepening of the alluvial channel to avoid infinite storage. Because steepening is never observed in natural system, we compute the alluvial widening factor value that varies between 3 to 11 times the width of the bedrock channel depending on riparian

  3. Species composition of the vegetation along the Sherichhu River, lower montane area of Eastern Bhutan

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    Tenzin Jamtsho


    Full Text Available An investigation of the riparian vegetation along the Sherichhu River, lower montane area of Eastern Bhutan was conducted from April to December 2015 to explore the plant communities in terms of species composition. A total number of 18 plots were placed within the remnant patches of the vegetation on either side of the river. In total, 172 species of vascular plant has been recorded. The cluster analysis suggested four types of plant communities in the study area viz., the MallotusDesmodium-Rhus shrubland and the Syzygium venosum woodland communities, which are located in V-shaped valleys and the Albizia-Flueggea woodland and Quercus glauca woodland communities located in U-shaped valleys. In broad-spectrum, the topographic features and environmental variables i.e. litter accumulation and flooding condition might also have some impact on the species composition of the plant communities of this vegetation.

  4. Impacts of Vegetation Growth on Reach-scale Flood Hydraulics in a Sand-bed River and the Implications for Vegetation-morphology Coevolution (United States)

    Box, S.; Wilcox, A. C.


    Vegetation alters flood hydraulics and geomorphic response, yet quantifying and predicting such responses across spatial and temporal scales remains challenging. Plant- and patch-scale studies consistently show that vegetation increases local hydraulic variability, yet reach-scale hydrodynamic models often assume vegetation has a spatially homogeneous effect on hydraulics. Using Nays2DH in iRIC (International River Interface Cooperative), we model the effect of spatially heterogeneous vegetation on a series of floods with varying antecedent vegetation conditions in a sand-bed river in western Arizona, taking advantage of over a decade of data on a system that experienced substantial geomorphic, hydrologic, and ecosystem changes. We show that pioneer woody seedlings (Tamarix, Populus, Salix) and cattail (Typha) increase local hydraulic variability, including velocity and bed shear stress, along individual cross sections, predominantly by decreasing velocity in zones of vegetation establishment and growth and increasing velocity in unvegetated areas, with analogous effects on shear stress. This was especially prominent in a study reach where vegetation growth contributed to thalweg incision relative to a vegetated bar. Evaluation of these results in the context of observed geomorphic response to floods elucidates mechanisms by which vegetation and channel morphology coevolve at a reach scale. By quantifying the influence of spatially heterogeneous vegetation on reach-scale hydraulics, we demonstrate that plant- and patch-scale research on vegetation hydraulics is applicable to ecogeomorphology at the reach scale.

  5. Vegetation Carbon Storage, Spatial Patterns and Response to Altitude in Lancang River Basin, Southwest China

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    Long Chen


    Full Text Available Vegetation plays a very important role of carbon (C sinks in the global C cycle. With its complex terrain and diverse vegetation types, the Lancang River Basin (LRB of southwest China has huge C storage capacity. Therefore, understanding the spatial variations and controlling mechanisms of vegetation C storage is important to understand the regional C cycle. In this study, data from a forest inventory and field plots were used to estimate and map vegetation C storage distribution in the LRB, to qualify the quantitative relationships between vegetation C density and altitude at sublot and township scale, and a linear model or polynomial model was used to identify the relationship between C density and altitude at two spatial scales and two statistical scales. The results showed that a total of 300.32 Tg C was stored in the LRB, an important C sink in China. The majority of C storage was contributed by forests, notably oaks. The vegetation C storage exhibited nonlinear variation with latitudinal gradients. Altitude had tremendous influences on spatial patterns of vegetation C storage of three geomorphological types in the LRB. C storage decreased with increasing altitude at both town and sublot scales in the flat river valley (FRV region and the mid-low mountains gorge (MMG region, and first increased then decreased in the alpine gorge (AG region. This revealed that, in southwest China, altitude changes the latitudinal patterns of vegetation C storage; especially in the AG area, C density in the mid-altitude (3100 m area was higher than that of adjacent areas.

  6. Assessment of hydrological regimes for vegetation on riparian wetlands in Han River Basin, Korea

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    Jaewon Kwak


    Full Text Available Hydrological regimes are regarded as one of the major determinants for wetland ecosystems, for they influence species composition, succession, productivity, and stability of vegetation communities. Since Korea launched the Four Major River Restoration Project in 2007, the water regimes of many of the riparian wetlands have changed, that is potentially affecting vegetation properties. For ecological conservation and management, it is important to connect hydrological characteristics and vegetation properties. The objective of this study is to investigate the influence of hydrological regimes on vegetation community, and develop a methodology that can connect them. Inundated exceedance probability (IEP and its district concept are suggested to gain insights into hydrological regimes on the Binae wetland that is rehabilitated by the Restoration Project in 2012 and belong to the riparian zone. Results of this study indicate that the areas with P = 0.08 or lower IEPs should have the disturbance for vegetation communities, or could be changed to a hydrophilic vegetation in the study area, and it should be considered in the restoration and rehabilitation project to conserve legally protected or endangered vegetation.

  7. River flow and riparian vegetation dynamics - implications for management of the Yampa River through Dinosaur National Monument (United States)

    Scott, Michael L; Friedman, Jonathan M.


    This report addresses the relation between flow of the Yampa River and occurrence of herbaceous and woody riparian vegetation in Dinosaur National Monument (DINO) with the goal of informing management decisions related to potential future water development. The Yampa River in DINO flows through diverse valley settings, from the relatively broad restricted meanders of Deerlodge Park to narrower canyons, including debris fan-affected reaches in the upper Yampa Canyon and entrenched meanders in Harding Hole and Laddie Park. Analysis of occurrence of all plant species measured in 1470 quadrats by multiple authors over the last 24 years shows that riparian vegetation along the Yampa River is strongly related to valley setting and geomorphic surfaces, defined here as active channel, active floodplain, inactive floodplain, and upland. Principal Coordinates Ordination arrayed quadrats and species along gradients of overall cover and moisture availability, from upland and inactive floodplain quadrats and associated xeric species like western wheat grass (Pascopyrum smithii), cheatgrass (Bromus tectorum), and saltgrass (Distichlis spicata) to active channel and active floodplain quadrats supporting more mesic species including sandbar willow (Salix exigua), wild licorice (Glycyrrhiza lepidota), and cordgrass (Spartina spp.). Indicator species analysis identified plants strongly correlated with geomorphic surfaces. These species indicate state changes in geomorphic surfaces, such as the conversion of active channel to floodplain during channel narrowing. The dominant woody riparian species along the Yampa River are invasive tamarisk (Tamarix ramosissima), and native Fremont cottonwood (Populus deltoides ssp. wislizenii), box elder (Acer negundo L. var. interius), and sandbar willow (Salix exigua). These species differ in tolerance of drought, salinity, inundation, flood disturbance and shade, and in seed size, timing of seed dispersal and ability to form root sprouts. These

  8. Aquatic vegetation were photographed from aircraft from Florida Bay, Indian River (Florida), and the Coast of Massachusetts (NODC Accession 0000411) (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Aerial photographs were taken of the aquatic vegetation of Florida Bay, Indian River (Florida), and the Coast of Massachusetts. Photographs were scanned and...

  9. Geomorphic and vegetation processes of the Willamette River floodplain, Oregon: current understanding and unanswered science questions (United States)

    Wallick, J. Rose; Jones, Krista L.; O'Connor, Jim E.; Keith, Mackenzie K.; Hulse, David; Gregory, Stanley V.


    decrease bed-material supply by an unknown amount because they limit bank erosion and entrainment of stored sediment. The rivers, geomorphic floodplain, and vegetation within the study area have changed noticeably in response to the alterations in floods and coarse sediment and wood transport. Widespread decreases have occurred in the rates of meander migration and avulsions and the number and diversity of landforms such as gravel bars, islands, and side channels. Dynamic and, in some cases, multi-thread river segments have become stable, single-thread channels. Preliminary observations suggest that forest area has increased within the active channel, further reducing the area of unvegetated gravel bars. Alterations to floods and sediment transport and ongoing channel, floodplain, and vegetation responses result in a modern Willamette River Basin. Here, the floodplain influenced by the modern flow and sediment regimes, or the functional floodplain, is narrower and inset with the broader and older geomorphic floodplain. The functional floodplain is flanked by higher elevation relict floodplain features that are no longer inundated by modern floods. The corridor of present- day active channel surfaces is narrower, enabling riparian vegetation to establish on formerly active gravel bar surfaces. The modern Willamette River Basin with its fundamental changes in the flood, sediment transport, and large wood regimes has implications for future habitat conditions. System-wide future trends probably include narrower floodplains and a lower diversity of landforms and habitats along the Willamette River and its major tributaries compared to historical patterns and today. Furthermore, specific conditions and future trends will probably vary between geologically stable, anthropogenically stable, and dynamic reaches. The middle and lower segments of the Willamette River are geologically stable, whereas the South Santiam and Middle Fork Willamette Rivers were historically dynamic, but

  10. Evolution of the vegetation system in the Heihe River basin in the last 2000 years

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    S. Li


    Full Text Available The response of vegetation systems to the long-term changes in climate, hydrology, and social–economic conditions in river basins is critical for sustainable river basin management. This study aims to investigate the evolution of natural and crop vegetation systems in the Heihe River basin (HRB over the past 2000 years. Archived Landsat images, historical land use maps and hydrological records were introduced to derive the long-term spatial distribution of natural and crop vegetation and the corresponding biomass levels. The major findings are that (1 both natural and crop vegetation experienced three development stages: a pre-development stage (before the Republic of China, a rapid development stage (Republic of China – 2000, and a post-development stage (after 2000. Climate and hydrological conditions did not show significant impacts over crop vegetation, while streamflow presented synchronous changes with natural vegetation in the first stage. For the second stage, warmer temperature and increasing streamflow were found to be important factors for the increase in both natural and crop vegetation in the middle reaches of the HRB. For the third stage, positive climate and hydrological conditions, together with policy interventions, supported the overall vegetation increase in both the middle and lower HRB; (2 there was a significantly faster increase in crop biomass than that of native vegetation since 1949, which could be explained by the technological development; and (3 the ratio of natural vegetation to crop vegetation decreased from 16 during the Yuan Dynasty to about 2.2 since 2005. This ratio reflects the reaction of land and water development to a changing climate and altering social–economic conditions at the river basin level; therefore, it could be used as an indicator of water and land management at river basins.

  11. Do invasive alien plants really threaten river bank vegetation? A case study based on plant communities typical for Chenopodium ficifolium—An indicator of large river valleys (United States)

    Nowak, Arkadiusz; Rola, Kaja


    Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resident and invasive alien species in vegetation plots along three rivers differing in terms of size and anthropogenic impact were also examined. Finally, the effect of invaders on the phytocoenoses typical for C. ficifolium was assessed. The frequency of C. ficifolium clearly decreased with an increasing distance from the river. Among natural habitats, the species mostly preferred the banks of large rivers. The vegetation plots developing on the banks of the three studied rivers differed in total species richness, the number and cover of resident, diagnostic and invasive alien species, as well as in species composition. Our research indicates that abiotic and anthropogenic factors are the most significant drivers of species richness and plant cover of riverbank vegetation, and invasive alien plants affect this type of vegetation to a small extent. PMID:29543919

  12. Do invasive alien plants really threaten river bank vegetation? A case study based on plant communities typical for Chenopodium ficifolium-An indicator of large river valleys. (United States)

    Nobis, Agnieszka; Nowak, Arkadiusz; Rola, Kaja


    Riparian zones are very rich in species but subjected to strong anthropogenic changes and extremely prone to alien plant invasions, which are considered to be a serious threat to biodiversity. Our aim was to determine the spatial distribution of Chenopodium ficifolium, a species demonstrating strong confinement to large river valleys in Central Europe and an indicator of annual pioneer nitrophilous vegetation developing on river banks, which are considered to be of importance to the European Community. Additionally, the habitat preferences of the species were analysed. Differences in the richness and abundance of species diagnostic for riverside habitats, as well as the contribution of resident and invasive alien species in vegetation plots along three rivers differing in terms of size and anthropogenic impact were also examined. Finally, the effect of invaders on the phytocoenoses typical for C. ficifolium was assessed. The frequency of C. ficifolium clearly decreased with an increasing distance from the river. Among natural habitats, the species mostly preferred the banks of large rivers. The vegetation plots developing on the banks of the three studied rivers differed in total species richness, the number and cover of resident, diagnostic and invasive alien species, as well as in species composition. Our research indicates that abiotic and anthropogenic factors are the most significant drivers of species richness and plant cover of riverbank vegetation, and invasive alien plants affect this type of vegetation to a small extent.

  13. Vegetation succession on river sediments along the Nakdong River, South Korea

    Czech Academy of Sciences Publication Activity Database

    Prach, Karel; Petřík, Petr; Brož, Z.; Song, J. S.


    Roč. 49, č. 4 (2014), 507-519 ISSN 1211-9520 R&D Projects: GA ČR(CZ) GAP505/11/0256; GA AV ČR IAA600050802 Institutional support: RVO:67985939 Keywords : ordination * the Four River Project * species richness Subject RIV: EH - Ecology, Behaviour Impact factor: 1.778, year: 2014

  14. Co-evolution of Riparian Vegetation and Channel Dynamics in an Aggrading Braided River System, Mount Pinatubo, Philippines (United States)

    Gran, K. B.; Michal, T.


    Increased bank stability by riparian vegetation in braided rivers can decrease bed reworking rates and focus the flow. The magnitude of influence and resulting channel morphology are functions of vegetation strength vs. channel dynamics, a concept encapsulated in a dimensionless ratio between timescales for vegetation growth and channel reworking known as T*. We investigate this relationship in an aggrading braided river at Mount Pinatubo, Philippines, and compare results to numerical and physical models. Gradual reductions in post-eruption sediment loads have reduced bed reworking rates, allowing vegetation to persist year-round and impact channel dynamics on the Pasig-Potrero and Sacobia Rivers. From 2009-2011, we collected data detailing vegetation extent, type, density, and root strength. Incorporating these data into RipRoot and BSTEM models shows cohesion due to roots increased from zero in unvegetated conditions to >10.2 kPa in densely-growing grasses. Field-based parameters were incorporated into a cellular model comparing vegetation growth and sediment mobility effects on braided channel dynamics. The model shows that both low sediment mobility and high vegetation strength lead to less active systems, reflecting trends observed in the field. An estimated T* between 0.8 - 2.3 for the Pasig-Potrero River suggests channels were mobile enough to maintain the braidplain width clear of vegetation and even experience slight gains in area through annual removal of existing vegetation. However, persistent vegetation focused flow and thus aggradation over the unvegetated fraction of braidplain, leading to an aggradational imbalance and transition to a more avulsive state. While physical models predict continued narrowing of the active braidplain as T* declines, the future trajectory of channel-vegetation interactions at Pinatubo as sedimentation rates decline appears more complicated due to strong seasonal variability in precipitation and sediment loads. By 2011

  15. Floodplain Vegetation Productivity and Carbon Cycle Dynamics of the Middle Fork Flathead River of Northwest Montana (United States)

    Oakins, A. J.; Kimball, J. S.; Relyea, S.; Stanford, J. A.


    River floodplains are vital natural features that store floodwaters, improve water quality, provide habitat, and create recreational opportunities. Recent studies have shown that strong interactions among flooding, channel and sediment movement, vegetation, and groundwater create a dynamic shifting habitat mosaic that promotes biodiversity and complex food webs. Multiple physical and environmental processes interact within these systems to influence forest productivity, including water availability, nutrient supply, soil texture, and disturbance history. This study is designed to quantify the role of groundwater depth and meteorology in determining spatial and temporal patterns of net primary productivity (NPP) within the Nyack floodplain of the Middle Fork Flathead River, Northwestern Montana. We examine three intensive field sites composed of mature, mixed deciduous and evergreen conifer forest with varying hydrologic and vegetative characteristics. We use a modified Biome-BGC ecosystem process model with field-collected data (LAI, increment growth cores, groundwater depth, vegetation sap-flow, and local meteorology) to describe the effects of floodplain groundwater dynamics on vegetation community structure, and carbon/nitrogen cycling. Initial results indicate that conifers are more sensitive than deeper-rooted deciduous species to variability in groundwater depth and meteorological conditions. Forest productivity also shows a non-linear response to groundwater depth. Sites with intermediate groundwater depths (0.2-0.5m) allow vegetation to maintain connectivity to groundwater over longer periods during the growing season, are effectively uncoupled from atmospheric constraints on photosynthesis, and generally have greater productivity. Shallow groundwater sites (<0.2m) are less productive due to the indirect effects of reduced soil aerobic decomposition and reduced plant available nitrogen.

  16. Radiological survey of shoreline vegetation from the Hanford Reach of the Columbia River, 1990--1992

    International Nuclear Information System (INIS)

    Antonio, E.J.; Poston, T.M.; Rickard, W.H. Jr.


    A great deal of interest exists concerning the seepage of radiologically contaminated groundwater into the Columbia River where it borders the US Department of Energy's Hanford Site (Hanford Reach). Areas of particular interest include the 100-N Area, the Old Hanford Townsite, and the 300 Area springs. While the radiological character of the seeps and springs along the Hanford Site shoreline has been studied, less attention has been given to characterizing the radionuclides that may be present in shoreline vegetation. The objective of this study was to characterize radionuclide concentrations in shoreline plants along the Hanford Reach of the Columbia River that were usable by humans for food or other purposes. Vegetation in two areas was found to have elevated levels of radionuclides. Those areas were the 100-N Area and the Old Hanford Townsite. There was also some indication of uranium accumulation in milfoil and onions collected from the 300 Area. Tritium was elevated above background in all areas; 60 Co and 9O Sr were found in highest concentrations in vegetation from the 100-N Area. Technetium-99 was found in 2 of 12 plants collected from the Old Hanford Townsite and 1 of 10 samples collected upstream from the Vernita Bridge. The concentrations of 137 Cs, 238 Pu, 239,240 Pu, and isotopes of uranium were just above background in all three areas (100-N Area, Old Hanford Townsite, and 300 Area)

  17. Radiological survey of shoreline vegetation from the Hanford Reach of the Columbia River, 1990--1992

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.; Poston, T.M.; Rickard, W.H. Jr.


    A great deal of interest exists concerning the seepage of radiologically contaminated groundwater into the Columbia River where it borders the US Department of Energy`s Hanford Site (Hanford Reach). Areas of particular interest include the 100-N Area, the Old Hanford Townsite, and the 300 Area springs. While the radiological character of the seeps and springs along the Hanford Site shoreline has been studied, less attention has been given to characterizing the radionuclides that may be present in shoreline vegetation. The objective of this study was to characterize radionuclide concentrations in shoreline plants along the Hanford Reach of the Columbia River that were usable by humans for food or other purposes. Vegetation in two areas was found to have elevated levels of radionuclides. Those areas were the 100-N Area and the Old Hanford Townsite. There was also some indication of uranium accumulation in milfoil and onions collected from the 300 Area. Tritium was elevated above background in all areas; {sup 60}Co and {sup 9O}Sr were found in highest concentrations in vegetation from the 100-N Area. Technetium-99 was found in 2 of 12 plants collected from the Old Hanford Townsite and 1 of 10 samples collected upstream from the Vernita Bridge. The concentrations of {sup 137}Cs, {sup 238}Pu, {sup 239,240}Pu, and isotopes of uranium were just above background in all three areas (100-N Area, Old Hanford Townsite, and 300 Area).

  18. The role of riparian vegetation density, channel orientation and water velocity in determining river temperature dynamics (United States)

    Garner, Grace; Malcolm, Iain A.; Sadler, Jonathan P.; Hannah, David M.


    A simulation experiment was used to understand the importance of riparian vegetation density, channel orientation and flow velocity for stream energy budgets and river temperature dynamics. Water temperature and meteorological observations were obtained in addition to hemispherical photographs along a ∼1 km reach of the Girnock Burn, a tributary of the Aberdeenshire Dee, Scotland. Data from nine hemispherical images (representing different uniform canopy density scenarios) were used to parameterise a deterministic net radiation model and simulate radiative fluxes. For each vegetation scenario, the effects of eight channel orientations were investigated by changing the position of north at 45° intervals in each hemispheric image. Simulated radiative fluxes and observed turbulent fluxes drove a high-resolution water temperature model of the reach. Simulations were performed under low and high water velocity scenarios. Both velocity scenarios yielded decreases in mean (≥1.6 °C) and maximum (≥3.0 °C) temperature as canopy density increased. Slow-flowing water resided longer within the reach, which enhanced heat accumulation and dissipation, and drove higher maximum and lower minimum temperatures. Intermediate levels of shade produced highly variable energy flux and water temperature dynamics depending on the channel orientation and thus the time of day when the channel was shaded. We demonstrate that in many reaches relatively sparse but strategically located vegetation could produce substantial reductions in maximum temperature and suggest that these criteria are used to inform future river management.

  19. Phase 1 summaries of radionuclide concentration data for vegetation, river water, drinking water, and fish

    International Nuclear Information System (INIS)

    Denham, D.H.; Dirkes, R.L.; Hanf, R.W.; Poston, T.M.; Thiede, M.E.; Woodruff, R.K.


    The objective of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate the radiation doses that individuals and populations could have received from nuclear operations at the Hanford Site since 1944. As part of the HEDR Project, the Environmental Monitoring Data Task (Task 05) staff assemble, evaluate, and summarize key historical measurements of radionuclide concentrations in the environment as a result of Hanford operations. The scope of work performed during Phase I included initiating the search, recovery, and inventory of environmental reports. Summaries of the environmental monitoring data that were recovered and evaluated are presented for specific periods of interest. These periods include vegetation monitoring data (primarily sagebrush) for the years 1945 through 1947, Columbia River water and drinking water monitoring data for the years 1963 through 1966, and fish monitoring data for the years 1964 through 1966. Concern was limited to those radionuclides identified as the most likely major contributors to the dose potentially received by the public during the times of interest: phosphorous-32, copper-64, zinc-65, arsenic-76, and neptunium-239 in Columbia River fish and drinking water taken from the river, and iodine-131 in vegetation. This report documents the achievement of the Phase I objectives of the Environmental Monitoring Data Task

  20. Expansion of the agricultural frontier on riparian vegetation of Santa Cruz River, Cuba

    Directory of Open Access Journals (Sweden)

    Felipe Carricarte Rodríguez


    Full Text Available The work was developed in the Los Amaros, the Santa Cruz river, Artemisa, Cuba. The objective was to evaluate how it influences the expansion of the agricultural frontier on riparian vegetation where the semi-deciduous mesophytic forest (BsdMe predominates. A floristic characterization was performed, identifying the effects of disturbances on the structure and composition of these forests and their relation to human disturbance. A semi-structured interview was applied to all landowners in the study area. Species richness, dominance, basal area, total number of individuals, width of the strip covered by trees and shrubs, and area without vegetation on both banks of the river, respectively were considered as variables. There are differences in the structure and patterns of diversity of the studied forest, as a result of disturbances, with the consequent reduction of species; also anthropogenic disturbances, are the main factors that explain changes in the structure of these forests. They are identified as major species: Cupania macrophylla A. Rich., Roystonea regia HBK O. F. Cook., Guarea guidonia L. Sleumer and Trichilia hirta  L. It is proposed to deepen the effect of the expansion of agriculture into other sectors of the river in interaction with local communities.

  1. The long-term legacy of geomorphic and riparian vegetation feedbacks on the dammed Bill Williams River, Arizona, USA (United States)

    Kui, Li; Stella, John C.; Shafroth, Patrick B.; House, P. Kyle; Wilcox, Andrew C.


    On alluvial rivers, fluvial landforms and riparian vegetation communities codevelop as a result of feedbacks between plants and abiotic processes. The influence of vegetation on river channel and floodplain geomorphology can be particularly strong on dammed rivers with altered hydrology and reduced flood disturbance. We used a 56-year series of aerial photos on the dammed Bill Williams River (Arizona, USA) to investigate how (a) different woody riparian vegetation types influence river channel planform and (b) how different fluvial landforms drive the composition of riparian plant communities over time. We mapped vegetation types and geomorphic surfaces and quantified how relations between fluvial and biotic processes covaried over time using linear mixed models. In the decades after the dam was built, woody plant cover within the river's bottomland nearly doubled, narrowing the active channel by 60% and transforming its planform from wide and braided to a single thread and more sinuous channel. Compared with native cottonwood–willow vegetation, nonnative tamarisk locally induced a twofold greater reduction in channel braiding. Vegetation expanded at different rates depending on the type of landform, with tamarisk cover on former high-flow channels increasing 17% faster than cottonwood–willow. Former low-flow channels with frequent inundation supported a greater increase in cottonwood–willow relative to tamarisk. These findings give insight into how feedbacks between abiotic and biotic processes in river channels accelerate and fortify changes triggered by dam construction, creating river systems increasingly distinct from predam ecological communities and landforms, and progressively more resistant to restoration of predam forms and processes.

  2. Potential for water salvage by removal of non-native woody vegetation from dryland river systems (United States)

    Doody, T.M.; Nagler, P.L.; Glenn, E.P.; Moore, G.W.; Morino, K.; Hultine, K.R.; Benyon, R.G.


    Globally, expansion of non-native woody vegetation across floodplains has raised concern of increased evapotranspiration (ET) water loss with consequent reduced river flows and groundwater supplies. Water salvage programs, established to meet water supply demands by removing introduced species, show little documented evidence of program effectiveness. We use two case studies in the USA and Australia to illustrate factors that contribute to water salvage feasibility for a given ecological setting. In the USA, saltcedar (Tamarix spp.) has become widespread on western rivers, with water salvage programs attempted over a 50-year period. Some studies document riparian transpiration or ET reduction after saltcedar removal, but detectable increases in river base flow are not conclusively shown. Furthermore, measurements of riparian vegetation ET in natural settings show saltcedar ET overlaps the range measured for native riparian species, thereby constraining the possibility of water salvage by replacing saltcedar with native vegetation. In Australia, introduced willows (Salix spp.) have become widespread in riparian systems in the Murray-Darling Basin. Although large-scale removal projects have been undertaken, no attempts have been made to quantify increases in base flows. Recent studies of ET indicate that willows growing in permanently inundated stream beds have high transpiration rates, indicating water savings could be achieved from removal. In contrast, native Eucalyptus trees and willows growing on stream banks show similar ET rates with no net water salvage from replacing willows with native trees. We conclude that water salvage feasibility is highly dependent on the ecohydrological setting in which the non-native trees occur. We provide an overview of conditions favorable to water salvage. Copyright ?? 2011 John Wiley & Sons, Ltd.

  3. Vegetation cover, avoided erosion and water quality in high Andean wetlands, Yeso River Basin (United States)

    León, Alejandro; Soto, Jorge; Seguel, Oscar; Pérez, Javier; Osses, Daniela; Leiva, Nicolás; Zerega, Linka


    Wetlands on the high Andes mountains near Santiago de Chile have been impacted by overgrazing and off-road tourists. We studied wetlands in El Yeso River basin. In February 2015 we established 36 exclusions and measured vegetation cover and height, biomass production in and out the exclusions starting in October. Water and undisturbed soil samples were collected. Data were analyzed statistically to estimate i) the recovery of vegetation, and ii) the influence of grazing and vehicle traffic on vegetation loss, and iii) impacts on soil and water quality. In areas with less intense traffic, the difference in vegetation coverage in and out the exclusions is 22% (± 11.4%); in areas with more intense traffic this difference is 16% (± 16%). Height of vegetation, in the less intense traffic areas, ranges from 6.25 cm (± 2.8) to 13.32 cm (± 6.3). With higher traffic it varies between 6.9 cm (± 3.1) and 13.6 cm (± 5.4). Biomass varies between 0.06 kg DM/m2 to 0.57 kg DM/m2 depending on botanical composition and date. After water circulates through the wetlands its content of nitrogen increases 37.33% to 0.37 mg N/l and the fecal coliforms 66.67% to 0.67 MPN/100 ml, because of cattle. On the contrary, turbidity decreases 20.67% to 0.21 UNT because sediments are captured by vegetation. We also estimated an avoided erosion rate, ranging between 1.23% and 31.87% (depending on the slope) due to the increase in coverage within the exclusions.

  4. Asynchronous changes in vegetation, runoff and erosion in the nile river watershed during the holocene. (United States)

    Blanchet, Cécile L; Frank, Martin; Schouten, Stefan


    The termination of the African Humid Period in northeastern Africa during the early Holocene was marked by the southward migration of the rain belt and the disappearance of the Green Sahara. This interval of drastic environmental changes was also marked by the initiation of food production by North African hunter-gatherer populations and thus provides critical information on human-environment relationships. However, existing records of regional climatic and environmental changes exhibit large differences in timing and modes of the wet/dry transition at the end of the African Humid Period. Here we present independent records of changes in river runoff, vegetation and erosion in the Nile River watershed during the Holocene obtained from a unique sedimentary sequence on the Nile River fan using organic and inorganic proxy data. This high-resolution reconstruction allows to examine the phase relationship between the changes of these three parameters and provides a detailed picture of the environmental conditions during the Paleolithic/Neolithic transition. The data show that river runoff decreased gradually during the wet/arid transition at the end of the AHP whereas rapid shifts of vegetation and erosion occurred earlier between 8.7 and ∼6 ka BP. These asynchronous changes are compared to other regional records and provide new insights into the threshold responses of the environment to climatic changes. Our record demonstrates that the degradation of the environment in northeastern Africa was more abrupt and occurred earlier than previously thought and may have accelerated the process of domestication in order to secure sustainable food resources for the Neolithic African populations.

  5. Improving the description of sunglint for accurate prediction of remotely sensed radiances

    Energy Technology Data Exchange (ETDEWEB)

    Ottaviani, Matteo [Light and Life Laboratory, Department of Physics and Engineering Physics, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030 (United States)], E-mail:; Spurr, Robert [RT Solutions Inc., 9 Channing Street, Cambridge, MA 02138 (United States); Stamnes, Knut; Li Wei [Light and Life Laboratory, Department of Physics and Engineering Physics, Stevens Institute of Technology, Castle Point on Hudson, Hoboken, NJ 07030 (United States); Su Wenying [Science Systems and Applications Inc., 1 Enterprise Parkway, Hampton, VA 23666 (United States); Wiscombe, Warren [NASA GSFC, Greenbelt, MD 20771 (United States)


    The bidirectional reflection distribution function (BRDF) of the ocean is a critical boundary condition for radiative transfer calculations in the coupled atmosphere-ocean system. Existing models express the extent of the glint-contaminated region and its contribution to the radiance essentially as a function of the wind speed. An accurate treatment of the glint contribution and its propagation in the atmosphere would improve current correction schemes and hence rescue a significant portion of data presently discarded as 'glint contaminated'. In current satellite imagery, a correction to the sensor-measured radiances is limited to the region at the edge of the glint, where the contribution is below a certain threshold. This correction assumes the sunglint radiance to be directly transmitted through the atmosphere. To quantify the error introduced by this approximation we employ a radiative transfer code that allows for a user-specified BRDF at the atmosphere-ocean interface and rigorously accounts for multiple scattering. We show that the errors incurred by ignoring multiple scattering are very significant and typically lie in the range 10-90%. Multiple reflections and shadowing at the surface can also be accounted for, and we illustrate the importance of such processes at grazing geometries.

  6. Response of Soil Fungi Community Structure to Salt Vegetation Succession in the Yellow River Delta. (United States)

    Wang, Yan-Yun; Guo, Du-Fa


    High-throughput sequencing technology was used to reveal the composition and distribution of fungal community structure in the Yellow River Delta under bare land and four kinds of halophyte vegetation (saline seepweed, Angiospermae, Imperata and Apocynum venetum [A. venetum]). The results showed that the soil quality continuously improved with the succession of salt vegetation types. The soil fungi richness of mild-salt communities (Imperata and A. venetum) was relatively higher, with Shannon index values of 5.21 and 5.84, respectively. The soil fungi richness of severe-salt-tolerant communities (saline seepweed, Angiospermae) was relatively lower, with Shannon index values of 4.64 and 4.66, respectively. The UniFrac metric values ranged from 0.48 to 0.67 when the vegetation was in different succession stages. A total of 60,174 valid sequences were obtained for the five vegetation types, and they were classified into Ascomycota, Basidiomycota, Chytridiomycota, Glomeromycota and Mucoromycotina. Ascomycota had the greatest advantage among plant communities of Imperata and A. venetum, as indicated by relative abundances of 2.69 and 69.97 %, respectively. Basidiomycota had the greatest advantage among mild-salt communities of saline seepweed and Angiospermae, with relative abundances of 9.43 and 6.64 %, respectively. Soil physical and chemical properties were correlated with the distribution of the fungi, and Mucor was significantly correlated with soil moisture (r = 0.985; P Soil quality, salt vegetation and soil fungi were influenced by each other.

  7. [Correlationships between the coverage of vegetation and the quality of groundwater in the lower reaches of the Tarim River]. (United States)

    Chen, Yong-jin; Chen, Ya-ning; Liu, Jia-zhen


    The variations vegetation coverage is the result of conjunct effects of inner and outer energy of the earth, however, the human activity always makes the coverage of vegetation change a lot. Based on the monitoring data of chemistry of groundwater and the coverage of vegetation from 2002 to 2007 in the lower reaches of Tarim River, relations between vegetation coverage and groundwater chemistry were studied. It is found that vegetation coverage at Sector A was more than 80%, and decreased from sector to sector, the coverage of Sector I was less than 10%. At the same sector, samples near to water source owned high coverage index, and samples far away from the river had low coverage index. The variations of pH in groundwater expressed similar regulation to vegetation coverage, that is, Sectors near the water source had higher pH index comparing than those far away. Regression between groundwater quality and vegetation coverage disclosed that the coverage of Populus euphratica climbed up along with increase of pH in groundwater, change of Tamarix ramosissima coverage expressed an opposite trend to the Populus euphratica with the same environmental factors. This phenomenon can interpret spatial distribution of Populus euphratica and Tamarix ramosissima in lower reaches of the Tarim River.

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

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


    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. Influence of aerosols, clouds, and sunglint on polarization spectra of Earthshine (United States)

    Emde, Claudia; Buras-Schnell, Robert; Sterzik, Michael; Bagnulo, Stefano


    Context. Ground-based observations of the Earthshine, I.e., the light scattered by Earth to the Moon, and then reflected back to Earth, simulate space observations of our planet and represent a powerful benchmark for the studies of Earth-like planets. Earthshine spectra are strongly linearly polarized, owing to scattering by molecules and small particles in the atmosphere of the Earth and surface reflection, and may allow us to measure global atmospheric and surface properties of planet Earth. Aims: We aim to interpret already published spectropolarimetric observations of the Earthshine by comparing them with new radiative transfer model simulations including a fully realistic three-dimensional (3D) surface-atmosphere model for planet Earth. Methods: We used the highly advanced Monte Carlo radiative transfer model MYSTIC to simulate polarized radiative transfer in the atmosphere of the Earth without approximations regarding the geometry, taking into account the polarization from surface reflection and multiple scattering by molecules, aerosol particles, cloud droplets, and ice crystals. Results: We have shown that Earth spectropolarimetry is highly sensitive to all these input parameters, and we have presented simulations of a fully realistic Earth atmosphere-surface model including 3D cloud fields and two-dimensional (2D) surface property maps. Our modeling results show that scattering in high ice water clouds and reflection from the ocean surface are crucial to explain the continuum polarization at longer wavelengths as has been reported in Earthshine observations taken at the Very Large Telescope in 2011 (3.8% and 6.6% at 800 nm, depending on which part of Earth was visible from the Moon at the time of the observations). We found that the relatively high degree of polarization of 6.6% can be attributed to light reflected by the ocean surface in the sunglint region. High ice-water clouds reduce the amount of absorption in the O2A band and thus explain the weak O2

  10. Spatial-temporal Evolution of Vegetation Coverage and Analysis of it’s Future Trends in Wujiang River Basin (United States)

    Xiao, Jianyong; Bai, Xiaoyong; Zhou, Dequan; Qian, Qinghuan; Zeng, Cheng; Chen, Fei


    Vegetation coverage dynamics is affected by climatic, topography and human activities, which is an important indicator reflecting the regional ecological environment. Revealing the spatial-temporal characteristics of vegetation coverage is of great significance to the protection and management of ecological environment. Based on MODIS NDVI data and the Maximum Value Composites (MVC), we excluded soil spectrum interference to calculate Fractional Vegetation Coverage (FVC). Then the long-term FVC was used to calculate the spatial pattern and temporal variation of vegetation in Wujiang River Basin from 2000 to 2016 by using Trend analysis and Hurst index. The relationship between topography and spatial distribution of FVC was analyzed. The main conclusions are as follows: (1) The multi-annual mean vegetation coverage reveals a spatial distribution variation characteristic of low value in midstream and high level in other parts of the basin, owing a mean value of 0.6567. (2) From 2000 to 2016, the FVC of the Wujiang River Basin fluctuated between 0.6110 and 0.7380, and the overall growth rate of FVC was 0.0074/a. (3) The area of vegetation coverage tending to improve is more than that going to degrade in the future. Grass land, Arable land and Others improved significantly; karst rocky desertification comprehensive management project lead to persistent vegetation coverage improvement of Grass land, Arable land and Others. Residential land is covered with obviously degraded vegetation, resulting of urban sprawl; (4) The spatial distribution of FVC is positively correlated with TNI. Researches of spatial-temporal evolution of vegetation coverage have significant meaning for the ecological environment protection and management of the Wujiang River Basin.

  11. Dependence of Wetland Vegetation on Hydrological Regime in a Large Floodplain Lake (Poyang Lake) in the Middle Yangtze River (United States)

    Zhang, Q.; Tan, Z.; Xu, X.


    Exemplified in the Yangtze River floodplain lake, Poyang Lake, investigations were carried out to examine the dependence of vegetation on hydrological variables. The Lake is one of the few lakes that remain naturally connected to the Yangtze River. The Lake surface expanses to 4000 km2 in wet seasons, and reduces to less than 1000 km2 in dry seasons, creating some 3000 km2 vital wetland habitats for many animals. Remote sensing was used to obtain the spatial distribution of wetland vegetations. A lake hydrodynamic model using MIKE 21 was employed to determine the variability of wetland inundation. In-situ high time frequency observations of climate, soil moisture, and groundwater depth were also conducted in a typical wetland transect of 1 km long. Vegetations were sampled periodically to obtain species composition, diversity and biomass. Results showed that the spatial distribution of vegetation highly depended on the inundation duration and depth. Optimal hydrological variables existed for the typical vegetations in Poyang Lake wetland. Numerical simulations using HYDRUS-1D further demonstrated that both groundwater depth and soil moisture had significant effects on the growth of vegetation and the water demand in terms of transpiration, even in a wet climate zone such as middle Yangtze River. It was found that the optimal groundwater depths existed for both above- and belowground biomass. Simulation scenarios indicated that climate changes and human modification of hydrology would affect the water usage of vegetation and may cause a strategic adaptation of the vegetation to the stressed hydrological conditions. The study revealed new knowledge on the high dependence of wetland vegetation on both surface water regime and groundwater depths, in wet climate zone. Outcomes of this study may provide support for an integrated management of balancing water resources development and wetland sustainability maintenance in Poyang Lake, and other floodplain wetlands, with

  12. Changes in planform geomorphology and vegetation of the Umatilla River during a 50-year period of diminishing peak flow (United States)

    Hughes, M. L.; McDowell, P. F.


    The Umatilla River of northeastern Oregon is a gravel-bedded, mixed pattern, salmonid-bearing channel-floodplain system typical of the Interior Columbia River Basin. Efforts to restore native salmonids in this region since the 1980's coupled with increased scrutiny of flood- and erosion-control activities have prompted a need for better understanding of the biogemorphic implications of flood disturbances. The goals of this study are: (1) to re-examine results of earlier studies of flood impacts on the Umatilla River in light of more recent flow records, and (2) to investigate the degree to which large floods have influenced existing patterns of channel-floodplain geomorphology and vegetation. Mapping of flowing channels, bars, scoured surfaces, and vegetation within the active channel from of aerial photos bracketing flood and inter-flood periods since 1964 indicates complex and spatially variable channel changes. In general, channel scour was the most consistent response to flooding. The direction (gain/loss) and magnitude of changes in bars and vegetation within the active channel, as well as the amount of lateral channel movement and changes in sinuosity, were generally inconsistent across flood events. The removal of vegetation by scour during floods was in many areas compensated by the capture of vegetation from the floodplain by avulsion and activation of secondary channels. To date, the geomorphic impacts of the 1964-65 flood-of-record have not been replicated, despite an overall increase in the frequency of smaller floods. Expansion of riparian vegetation in recent decades has mainly occurred in areas disturbed by scour and bar deposition during the 1964-65 floods. Vegetative succession during this period has caused contraction of the active channel such that it now appears much as it did before the 1964-65 floods. These results underscore the importance of large floods as drivers of biogeormphic processes and patterns over timescales relevant to river

  13. Seasonality in ENSO-related precipitation, river discharges, soil moisture, and vegetation index in Colombia (United States)

    Poveda, GermáN.; Jaramillo, Alvaro; Gil, Marta MaríA.; Quiceno, Natalia; Mantilla, Ricardo I.


    An analysis of hydrologic variability in Colombia shows different seasonal effects associated with El Niño/Southern Oscillation (ENSO) phenomenon. Spectral and cross-correlation analyses are developed between climatic indices of the tropical Pacific Ocean and the annual cycle of Colombia's hydrology: precipitation, river flows, soil moisture, and the Normalized Difference Vegetation Index (NDVI). Our findings indicate stronger anomalies during December-February and weaker during March-May. The effects of ENSO are stronger for streamflow than for precipitation, owing to concomitant effects on soil moisture and evapotranspiration. We studied time variability of 10-day average volumetric soil moisture, collected at the tropical Andes of central Colombia at depths of 20 and 40 cm, in coffee growing areas characterized by shading vegetation ("shaded coffee"), forest, and sunlit coffee. The annual and interannual variability of soil moisture are highly intertwined for the period 1997-1999, during strong El Niño and La Niña events. Soil moisture exhibited greater negative anomalies during 1997-1998 El Niño, being strongest during the two dry seasons that normally occur in central Colombia. Soil moisture deficits were more drastic at zones covered by sunlit coffee than at those covered by forest and shaded coffee. Soil moisture responds to wetter than normal precipitation conditions during La Niña 1998-1999, reaching maximum levels throughout that period. The probability density function of soil moisture records is highly skewed and exhibits different kinds of multimodality depending upon land cover type. NDVI exhibits strong negative anomalies throughout the year during El Niños, in particular during September-November (year 0) and June-August (year 0). The strong negative relation between NDVI and El Niño has enormous implications for carbon, water, and energy budgets over the region, including the tropical Andes and Amazon River basin.

  14. Vegetation and vascular flora of the Mekong River, Kratie and Steung Treng Provinces, Cambodia

    Directory of Open Access Journals (Sweden)

    James F. Maxwell


    Full Text Available A preliminary and detailed botanical survey of the islands in the Mekong River between Kratie and Steung Treng was done. This area includes the most biologically intact and threatened riparian and terrestrial ecosystems along the river in Cambodia. The vegetation includes six riverine zones and four terrestrial facies. Riverine habitats are mostly intact while the terrestrial vegetation ranges from destroyed to degraded. Effective conservation measures are required to stop further habitat destruction and loss of biodiversity. One new species, 23 records for the Cambodian flora, and a total of 690 species were collected. Detailed descriptions of all habitats, a database, and photographs are included. Increased exploitative human settlement in the area has caused drastic environmental changes with extensive deforestation and hunting. The forests are grazed, burned, logged, and often cleared for agricultural use without effective control. Sustainable management and scientifically acceptable development must be implemented before the area is totally ruined. Properly conceived reforestation is urgently required as well as a conservation education project aimed directly at the people living in the area. Unless effective restraints are implemented the area will become biologically destitute and will not be able to provide the natural resources that people require--in short, the area will become uninhabitable. Restoration of degraded or destroyed places will be impossible or far more difficult than conservation and intelligent management of presently endangered places. The potential for profitable eco-tourism should also be considered since tourists will certainly want to visit natural ecosystems on some of the islands. Only if local people are directly involved in eco-tourism and understand the necessity of conservation can this activity be successful. It is strongly recommended that continued botanical research be conducted in the area in order to

  15. Analysis of vegetation condition and its relationship with meteorological variables in the Yarlung Zangbo River Basin of China

    Directory of Open Access Journals (Sweden)

    X. Han


    Full Text Available The Yarlung Zangbo River Basin is located in the southwest border of China, which is of great significance to the socioeconomic development and ecological environment of Southwest China. Normalized Difference Vegetation Index (NDVI is an important index for investigating the change of vegetation cover, which is widely used as the representation value of vegetation cover. In this study, the NDVI is adopted to explore the vegetation condition in the Yarlung Zangbo River Basin during the recent 17 years, and the relationship between NDVI and meteorological variables has also been discussed. The results show that the annual maximum value of NDVI usually appears from July to September, in which August occupies a large proportion. The minimum value of NDVI appears from January to March, in which February takes up most of the percentage. The higher values of NDVI are generally located in the lower elevation area. When the altitude is higher than 3250 m, NDVI began to decline gradually, and the NDVI became gradual stabilization as the elevation is up to 6000 m. The correlation coefficient between NDVI and precipitation in the Yarlung Zangbo River Basin is greater than that with temperature. The Hurst index of the whole basin is 0.51, indicating that the NDVI of the Yarlung Zangbo River Basin shows a weak sustainability.

  16. Linking vegetation pattern to hydrology and hydrochemistry in a montane river floodplain, the Šumava National Park, Central Europe

    Czech Academy of Sciences Publication Activity Database

    Bufková, I.; Prach, Karel


    Roč. 14, - (2006), s. 317-327 ISSN 0923-4861 R&D Projects: GA ČR GA526/00/1442 Institutional research plan: CEZ:AV0Z60050516 Keywords : diversity * river floodplain * vegetation Subject RIV: EF - Botanics

  17. Quantification of the impact of macrophytes on oxygen dynamics and nitrogen retention in a vegetated lowland river

    NARCIS (Netherlands)

    Desmet, N.J.S.; Van Belleghem, S.; Seuntjens, P.; Bouma, T.J.; Buis, K.; Meire, P.


    When macrophytes are growing in the river, the vegetation induces substantial changes to the water quality. Some effects are the result of direct interactions, such as photosynthetic activity or nutrient uptake, whereas others may be attributed to indirect effects of the water plants on

  18. Bioavailability of iron and zinc in green leafy vegetables growing in river side and local areas of Allahabad district

    Directory of Open Access Journals (Sweden)

    Bhawna Srivastava


    Full Text Available Introduction: Green Leafy Vegetables (GLVs are the treasure trove of many micronutrients.Objective: The aim of the study is to find out the commonly growing vegetables in river side and local areas of Allahabad district and to access the bioavailability of iron and zinc in selected green leafy vegetables of river side and local areas of Allahabad district.Methods: Five to four commonly grown green leafy vegetables were selected from the Arailghat, Baluaghat, Gaughat, Mahewa, Muirabad, Rajapur, Rasullabad for the study. Total iron and zinc in sample were estimated by AOAC (2005 and bioavailability of zinc and iron from various food samples was determined in vitro method described by Luten (1996. Appropriate statistical technique was adopted for analysis of study.Result: Soya leaves, Radish leaves, Amaranth, Spinach were grown in both the areas except Kulpha and Karamwa, which are commonly grown in river side area. There was a significant difference between the bioavailability of iron and zinc in GLV grown in local and river side area.Conclusion: Hence it can be concluded that there is a contamination of heavy metals which binds with the iron and zinc and make them less bioavailable in the selected GLV.

  19. Identification of heavy metals on vegetables at the banks of Kaligarang river using neutron analysis activation method (United States)

    Yulianti, D.; Marwoto, P.; Fianti


    This research aims to determine the type, concentration, and distribution of heavy metals in vegetables on the banks river Kaligarang using Neutron Analysis Activation (NAA) Method. The result is then compared to its predefined threshold. Vegetable samples included papaya leaf, cassava leaf, spinach, and water spinach. This research was conducted by taking a snippet of sediment and vegetation from 4 locations of Kaligarang river. These snippets are then prepared for further irradiated in the reactor for radioactive samples emiting γ-ray. The level of γ-ray energy determines the contained elements of sample that would be matched to Neutron Activation Table. The results showed that vegetablesat Kaligarang are containing Cr-50, Co-59, Zn-64, Fe-58, and Mn-25, and well distributed at all research locations. Furthermore, the level of the detected metal elements is less than the predefined threshold.

  20. Quantification of the impact of macrophytes on oxygen dynamics and nitrogen retention in a vegetated lowland river (United States)

    Desmet, N. J. S.; Van Belleghem, S.; Seuntjens, P.; Bouma, T. J.; Buis, K.; Meire, P.

    When macrophytes are growing in the river, the vegetation induces substantial changes to the water quality. Some effects are the result of direct interactions, such as photosynthetic activity or nutrient uptake, whereas others may be attributed to indirect effects of the water plants on hydrodynamics and river processes. This research focused on the direct effect of macrophytes on oxygen dynamics and nutrient cycling. Discharge, macrophyte biomass density, basic water quality, dissolved oxygen and nutrient concentrations were in situ monitored throughout the year in a lowland river (Nete catchment, Belgium). In addition, various processes were investigated in more detail in multiple ex situ experiments. The field and aquaria measurement results clearly demonstrated that aquatic plants can exert considerable impact on dissolved oxygen dynamics in a lowland river. When the river was dominated by macrophytes, dissolved oxygen concentrations varied from 5 to 10 mg l -1. Considering nutrient retention, it was shown that the investigated in-stream macrophytes could take up dissolved inorganic nitrogen (DIN) from the water column at rates of 33-50 mg N kgdry matter-1 h. And DIN fluxes towards the vegetation were found to vary from 0.03 to 0.19 g N ha -1 h -1 in spring and summer. Compared to the measured changes in DIN load over the river stretch, it means that about 3-13% of the DIN retention could be attributed to direct nitrogen uptake from the water by macrophytes. Yet, the role of macrophytes in rivers should not be underrated as aquatic vegetation also exerts considerable indirect effects that may have a greater impact than the direct fixation of nutrients into the plant biomass.

  1. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.; Bhatt, U.S.


    increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases...... in vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime....

  2. Phenological response of vegetation to upstream river flow in the Heihe Rive basin by time series analysis of MODIS data

    Directory of Open Access Journals (Sweden)

    L. Jia


    Full Text Available Liquid and solid precipitation is abundant in the high elevation, upper reach of the Heihe River basin in northwestern China. The development of modern irrigation schemes in the middle reach of the basin is taking up an increasing share of fresh water resources, endangering the oasis and traditional irrigation systems in the lower reach. In this study, the response of vegetation in the Ejina Oasis in the lower reach of the Heihe River to the water yield of the upper catchment was analyzed by time series analysis of monthly observations of precipitation in the upper and lower catchment, river streamflow downstream of the modern irrigation schemes and satellite observations of vegetation index. Firstly, remotely sensed NDVI data acquired by Terra-MODIS are used to monitor the vegetation dynamic for a seven years period between 2000 and 2006. Due to cloud-contamination, atmospheric influence and different solar and viewing angles, however, the quality and consistence of time series of remotely sensed NDVI data are degraded. A Fourier Transform method – the Harmonic Analysis of Time Series (HANTS algorithm – is used to reconstruct cloud- and noise-free NDVI time series data from the Terra-MODIS NDVI dataset. Modification is made on HANTS by adding additional parameters to deal with large data gaps in yearly time series in combination with a Temporal-Similarity-Statistics (TSS method developed in this study to seek for initial values for the large gap periods. Secondly, the same Fourier Transform method is used to model time series of the vegetation phenology. The reconstructed cloud-free NDVI time series data are used to study the relationship between the water availability (i.e. the local precipitation and upstream water yield and the evolution of vegetation conditions in Ejina Oasis from 2000 to 2006. Anomalies in precipitation, streamflow, and vegetation index are detected by comparing each year with the average year. The results showed that

  3. Potential effects of elevated base flow and midsummer spike flow experiments on riparian vegetation along the Green River (United States)

    Friedman, Jonathan M.


    The Upper Colorado River Endangered Fish Recovery Program has requested experimental flow releases from Flaming Gorge Dam for (1) elevated summer base flows to promote larval endangered Colorado pikeminnow, and (2) midsummer spike flows to disadvantage spawning invasive smallmouth bass. This white paper explores the effects of these proposed flow modifications on riparian vegetation and sediment deposition downstream along the Green River. Although modest in magnitude, the elevated base flows and possible associated reductions in magnitude or duration of peak flows would exacerbate a long-term trend of flow stabilization on the Green River that is already leading to proliferation of vegetation including invasive tamarisk along the channel and associated sediment deposition, channel narrowing and channel simplification. Midsummer spike flows could promote establishment of late-flowering plants like tamarisk. Because channel narrowing and simplification threaten persistence and quality of backwater and side channel features needed by endangered fish, the proposed flow modifications could lead to degradation of fish habitat. Channel narrowing and vegetation encroachment could be countered by increases in peak flows or reductions in base flows in some years and by prescription of rapid flow declines following midsummer spike flows. These strategies for reducing vegetation encroachment would need to be balanced with flow

  4. Mechanisms of vegetation-induced channel narrowing of an unregulated canyon river: Results from a natural field-scale experiment (United States)

    Manners, Rebecca B.; Schmidt, John C.; Scott, Michael L.


    The lower Yampa River in Yampa Canyon, western Colorado serves as a natural, field-scale experiment, initiated when the invasive riparian plant, tamarisk (Tamarix spp.), colonized an unregulated river. In response to tamarisk's rapid invasion, the channel narrowed by 6% in the widest reaches since 1961. Taking advantage of this unique setting, we reconstructed the geomorphic and vegetation history in order to identify the key mechanisms for which, in the absence of other environmental perturbations, vegetation alters fluvial processes that result in a narrower channel. From our reconstruction, we identified a distinct similarity in the timing and magnitude of tamarisk encroachment and channel change, albeit with a lag in the channel response, thus suggesting tamarisk as the driving force. Within a decade of establishment, tamarisk effectively trapped sediment and, as a result, increased floodplain construction rates. Increasing tamarisk coverage over time also reduced the occurrence of floodplain stripping. Tamarisk recruitment was driven by both hydrologic and hydraulic variables, and the majority of tamarisk plants (84%) established below the stage of the 2-year flood. Thus, upon establishment nearly all plants regularly interact with the flow and sediment transport field. Our analyses were predicated on the hypothesis that the flow regime of the Yampa River was stationary, and that only the riparian vegetation community had changed. While not heavily impacted by water development, we determined that some aspects of the flow regime have shifted. However, this shift, which involved the clustering in time of extremely wet and dry years, did not influence fluvial processes directly. Instead these changes directly impacted riparian vegetation and changes in vegetation cover, in turn, altered fluvial processes. Today, the rate of channel change and new tamarisk recruitment is small. We believe that the rapid expansion of tamarisk and related floodplain construction

  5. Vegetation anomalies associated with the ENSO phenomenon in the Cauca river valley, Colombia

    Directory of Open Access Journals (Sweden)

    J. M. Valencia


    Full Text Available The main factors affecting the production and yield of sugarcane are variety, agronomic management, soil type and climate, of which the first three there is some control, while the climate is one factor of which you cannot have any control, therefore, it should be monitored. Colombia, being located in the equatorial pacific, is affected by two atmospheric oceanic phenomena known as “El Niño” and “La Niña”, which make up the climatic phenomenon of ENSO (El Niño-Southern Oscillation and affect the quantity and the number of days with rainfall and influences the production of sugarcane. The objective of this work is to identify spatially and temporally the zones with greater and lower impact of the ENSO phenomenon in the cultivation of sugarcane in Colombia through the use of the Standard Vegetation Index (SVI and the Rainfall Anomally Index (RAI using EVI/MODIS images and precipitation data from meteorological stations on a quarterly basis for the period 2000-2015. A similar trend was found between both indices in the “El Niño” and “Neutral” seasons, while in the “La Niña” season the RAI tended to rise while the SVI decreased when the RAI was very high, this tendency being much more marked in areas with floods caused by the overflow of the main rivers. In addition, a comparison was made between the SVI index and a productivity anomaly index (IAP, finding a direct correlation between both (R2 = 0.4, p<0.001. This work showed that through the use of vegetation indexes, a temporal analysis of the impact of climate on an agricultural crop can be carried out, especially with ENSO conditions.

  6. Seed banks as a source of vegetation regeneration to support the recovery of degraded rivers: A comparison of river reaches of varying condition. (United States)

    O'Donnell, Jessica; Fryirs, Kirstie A; Leishman, Michelle R


    Anthropogenic disturbance has contributed to widespread geomorphic adjustment and the degradation of many rivers. This research compares for river reaches of varying condition, the potential for seed banks to support geomorphic river recovery through vegetation regeneration. Seven river reaches in the lower Hunter catchment of south-eastern Australia were assessed as being in poor, moderate, or good condition, based on geomorphic and ecological indicators. Seed bank composition within the channel and floodplain (determined in a seedling emergence study) was compared to standing vegetation. Seed bank potential for supporting geomorphic recovery was assessed by measuring native species richness, and the abundance of different plant growth forms, with consideration of the roles played by different growth forms in geomorphic adjustment. The exotic seed bank was considered a limiting factor for achieving ecological restoration goals, and similarly analysed. Seed bank native species richness was comparable between the reaches, and regardless of condition, early successional and pioneer herbs, sedges, grasses and rushes dominated the seed bank. The capacity for these growth forms to colonise and stabilise non-cohesive sediments and initiate biogeomorphic succession, indicates high potential for the seed banks of even highly degraded reaches to contribute to geomorphic river recovery. However, exotic propagules increasingly dominated the seed banks of moderate and poor condition reaches and reflected increasing encroachment by terrestrial exotic vegetation associated with riparian degradation. As the degree of riparian degradation increases, the resources required to control the regeneration of exotic species will similarly increase, if seed bank-based regeneration is to contribute to both geomorphic and ecological restoration goals. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Vegetation Response to Changing Climate - A Case Study from Gandaki River Basin in Nepal Himalaya (United States)

    Panthi, J., Sr.; Kirat, N. H.; Dahal, P.


    The climate of the Himalayan region is changing rapidly - temperature is increasingly high and rainfall has become unpredictable. IPCC predicts that average annual mean temperature over the Asian land mass, including the Himalayas, will increase by about 3°C by the 2050s and about 5°C by the 2080s and the average annual precipitation in this region will increase by 10-30% by 2080s. Climate and the human activities can influence the land cover status and the eco-environmental quality. There are enough evidences that there is strong interaction between climate variability and ecosystems. A project was carried out in Gandaki river basin in central Nepal to analyze the relationship of NDVI vegetation index with the temperature, rainfall and snowcover information. The relationships were analyzed for different landuses classes-grassland, forest and agriculture. Results show that the snowcover area is decreasing at the rate of 0.15% per year in the basin. The NDVI shows seasonal fluctuations and lightly correlated with the rainfall and temperature.

  8. Feições Oceanográficas em Imagens MODIS na Condição de Sunglint: Exemplos para a Costa Sudeste Brasileira

    Directory of Open Access Journals (Sweden)

    Lucas Barbedo de Freitas

    Full Text Available Resumo Imagens ópticas e no infravermelho-próximo adquiridas por sensores remotos em condição de reflexão especular bidirecional entre o sol, a superfície do mar e o sensor (condição de sunglint podem ser utilizadas para identificar filmes, feições, processos oceanográficos e meteorológicos atuantes sobre a superfície marinha. Imagens do sensor orbital Moderate Resolution Imaging Spectroradiometer (MODIS em condição de sunglint na plataforma continental sudeste brasileira foram processadas e analisadas, permitindo identificar feições como a borda Oeste da Corrente do Brasil, meandramentos e vórtices de mesoescala, ondas internas solitárias, rolos atmosféricos e filmes superficiais de origem biogênica e mineral. Uma correção atmosférica mais apropriada para detecção de feições no sunglint é aprensentada, assim como, detalhes sobre a geometria de aquisição. A dependência geométrica do sunglint torna sua ocorrência mais favorável entre outubro e fevereiro na região de estudo quando ocorrem zênites solares mais propícios. Os mecanismos e processos que permitem identificar estas feições no sunglint foram descritos e ilustrados. A partir deste entendimento, as complexas feições identificadas podem ser interpretadas e aplicadas na oceanografia operacional e detecção de vazamentos de óleo na superfície do mar, bem como, para melhorar nosso entendimento sobre os processos físicos e biológicos do meio marinho.

  9. Evaluation of ERTS data for certain oceanographic uses. [sunglint, algal bloom, water temperature, upwelling, and turbidity of Great Lakes waters (United States)

    Strong, A. E. (Principal Investigator)


    The author has identified the following significant results. (1) Sunglint effects over water can be expected in ERTS-1 images whenever solar elevations exceed 55 deg. (2) Upwellings were viewed coincidently by ERTS-1 and NOAA-2 in Lake Michigan on two occasions during August 1973. (3) A large oil slick was identified 100 km off the Maryland coast in the Atlantic Ocean. Volume of the oil was estimated to be least 200,000 liters (50,000 gallons). (4) ERTS-1 observations of turbidity patterns in Lake St. Clair provide circulation information that correlates well with physical model studies made 10 years ago. (5) Good correlation has been established between ERTS-1 water color densities and NOAA-2 thermal infrared surface temperature measurements. Initial comparisons have been made in Lake Erie during March 1973.

  10. 1998 Annual Status Report: Submersed and Floating-Leaf Vegetation in Pools 4, 8, 13, and 26 and La Grange Pool of the Upper Mississippi River System

    National Research Council Canada - National Science Library

    Yin, Yao


    Aquatic vegetation was investigated in five navigation pools in the Upper Mississippi River System using a new protocol named 'stratified random sampling' or SRS protocol for the first time in 1998...

  11. Association analysis between spatiotemporal variation of vegetation greenness and precipitation/temperature in the Yangtze River Basin (China). (United States)

    Cui, Lifang; Wang, Lunche; Singh, Ramesh P; Lai, Zhongping; Jiang, Liangliang; Yao, Rui


    The variation in vegetation greenness provides good understanding of the sustainable management and monitoring of land surface ecosystems. The present paper discusses the spatial-temporal changes in vegetation and controlling factors in the Yangtze River Basin (YRB) using Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI) for the period 2001-2013. Theil-Sen Median trend analysis, Pearson correlation coefficients, and residual analysis have been used, which shows decreasing trend of the annual mean NDVI over the whole YRB. Spatially, the regions with significant decreasing trends were mainly located in parts of central YRB, and pronounced increasing trends were observed in parts of the eastern and western YRB. The mean NDVI during spring and summer seasons increased, while it decreased during autumn and winter seasons. The seasonal mean NDVI shows spatial heterogeneity due to the vegetation types. The correlation analysis shows a positive relation between NDVI and temperature over most of the YRB, whereas NDVI and precipitation show a negative correlation. The residual analysis shows an increase in NDVI in parts of eastern and western YRB and the decrease in NDVI in the small part of Yangtze River Delta (YRD) and the mid-western YRB due to human activities. In general, climate factors were the principal drivers of NDVI variation in YRB in recent years.

  12. Responses of Vegetation Growth to Climatic Factors in Shule River Basin in Northwest China: A Panel Analysis

    Directory of Open Access Journals (Sweden)

    Jinghui Qi


    Full Text Available The vegetation response to climatic factors is a hot topic in global change research. However, research on vegetation in Shule River Basin, which is a typical arid region in northwest China, is still limited, especially at micro scale. On the basis of Moderate-resolution Imaging Spectroradiometer (MODIS Normalized Difference Vegetation Index (NDVI data and daily meteorological data, employing panel data models and other mathematical models, the aim of this paper is to reveal the interactive relationship between vegetation variation and climatic factors in Shule River Basin. Results show that there is a widespread greening trend in the whole basin during 2000–2015, and 80.28% of greening areas (areas with vegetation improvement are distributed over upstream region, but the maximum vegetation variation appears in downstream area. The effects of climate change on NDVI lag about half to one month. The parameters estimated using panel data models indicate that precipitation and accumulated temperature have positive contribution to NDVI. With every 1-mm increase in rainfall, NDVI increases by around 0.223‰ in upstream area and 0.6‰ in downstream area. With every 1-°C increase in accumulated temperature, NDVI increases by around 0.241‰ in upstream area and 0.174‰ in downstream area. Responses of NDVI to climatic factors are more sensitive when these factors are limiting than when they are not limiting. NDVI variation has performance in two seasonal and inter-annual directions, and the range of seasonal change is far more than that of inter-annual change. The inverted U-shaped curve of the variable intercepts reflects the seasonal change. Our results might provide some scientific basis for the comprehensive basin management.

  13. River floodplain vegetation classification using multi-temporal high-resolution colour infrared UAV imagery.

    NARCIS (Netherlands)

    van Iersel, W.K.; Straatsma, M.W.; Addink, E.A.; Middelkoop, H.


    To evaluate floodplain functioning, monitoring of its vegetation is essential. Although airborne imagery is widely applied for this purpose, classification accuracy (CA) remains low for grassland (< 88%) and herbaceous vegetation (<57%) due to the spectral and structural similarity of these

  14. Vegetation response to invasive Tamarix control in southwestern U.S. rivers: a collaborative study including 416 sites. (United States)

    González, Eduardo; Sher, Anna A; Anderson, Robert M; Bay, Robin F; Bean, Daniel W; Bissonnete, Gabriel J; Bourgeois, Bérenger; Cooper, David J; Dohrenwend, Kara; Eichhorst, Kim D; El Waer, Hisham; Kennard, Deborah K; Harms-Weissinger, Rebecca; Henry, Annie L; Makarick, Lori J; Ostoja, Steven M; Reynolds, Lindsay V; Robinson, W Wright; Shafroth, Patrick B


    Most studies assessing vegetation response following control of invasive Tamarix trees along southwestern U.S. rivers have been small in scale (e.g., river reach), or at a regional scale but with poor spatial-temporal replication, and most have not included testing the effects of a now widely used biological control. We monitored plant composition following Tamarix control along hydrologic, soil, and climatic gradients in 244 treated and 172 reference sites across six U.S. states. This represents the largest comprehensive assessment to date on the vegetation response to the four most common Tamarix control treatments. Biocontrol by a defoliating beetle (treatment 1) reduced the abundance of Tamarix less than active removal by mechanically using hand and chain-saws (2), heavy machinery (3) or burning (4). Tamarix abundance also decreased with lower temperatures, higher precipitation, and follow-up treatments for Tamarix resprouting. Native cover generally increased over time in active Tamarix removal sites, however, the increases observed were small and was not consistently increased by active revegetation. Overall, native cover was correlated to permanent stream flow, lower grazing pressure, lower soil salinity and temperatures, and higher precipitation. Species diversity also increased where Tamarix was removed. However, Tamarix treatments, especially those generating the highest disturbance (burning and heavy machinery), also often promoted secondary invasions of exotic forbs. The abundance of hydrophytic species was much lower in treated than in reference sites, suggesting that management of southwestern U.S. rivers has focused too much on weed control, overlooking restoration of fluvial processes that provide habitat for hydrophytic and floodplain vegetation. These results can help inform future management of Tamarix-infested rivers to restore hydrogeomorphic processes, increase native biodiversity and reduce abundance of noxious species. © 2017 by the

  15. Floodplain-wide coupling of flooding and vegetation patterns in the Tonle Sap of the Mekong River (United States)

    Arias, M. E.; Haberstroh, C.


    Floodplain vegetation is one of the prime drivers of ecosystem productivity, thus floodplain-wide monitoring is critical to ensure the well-being of these ecosystems and the important services they provide to riparian societies. Therefore, the objective of this presentation is to introduce a novel methodology to monitor long-term and large-scale patterns of rooted vegetation in seasonally inundated floodplains. We applied this methodology to an floodplain area of ac. 18,000 km2 in the Tonle Sap (Cambodia), a complex hydro-ecological system directly connected to the Mekong River. The overall hypothesis of this study is that floodplain vegetation condition is dictated by gradients of disturbance from the uplands and from the flood-pulse itself. We first demonstrate that spatial vegetation patterns represented by the normalized difference vegetation index (NDVI) during the dry season -when interference from cloud cover and partial inundation is minimal- correspond well to meaningful land use/land cover groups as well as canopy cover data collected in the field. Annual trends (2000-2016) in NDVI spatial distribution showed that the modality of dry season NDVI is largely governed by the magnitude of flooding in the antecedent hydrological year. Indeed, we found a significant relationship between flood duration -defined as the number of months annually a floodplain pixel remains flooded- and floodplain-wide NDVI. We also determined that ac. 115 km2 yr-1 of the highest quality vegetation, were replaced by fallow land during the period of study. This research has important insights on the main drivers of floodplain vegetation in the Tonle Sap, and the proposed methodology, using data from freely available worldwide satellite imagery (MODIS), promises to be an effective method to monitor ecosystem change in large floodplains across the world.

  16. Spatiotemporal Variability in Topographic and Vegetative Controls on Basin-Wide Snow Distribution in the Tuolumne River Basin (United States)

    Bolliger, I. W.; Molotch, N. P.


    An accurate empirical characterization of topographic and vegetative controls on snow distribution can lead to a greater understanding of the underlying physical processes and an increased ability to downscale lower-resolution observations. As improved water resource forecast methods are sought to address climate-driven nonstationarity in snow distributions, constraining our uncertainty in topographic and vegetative controls on these distributions becomes imperative. The Airborne Snow Observatory (ASO) LiDAR-based observation campaign provides a novel dataset with the necessary spatiotemporal extent and resolution for rigorous assessment of spatiotemporal variance in topographic and vegetative controls. In this study, we examine ASO measurements from 2013-2016 in the Tuolumne River Basin, exploring relationships to topographic and vegetation features derived from analogous snow-free LiDAR flights. To address nonlinearities in these relationships, we use single and ensemble regression tree approaches and assess metrics of feature importance, while for greater interpretability, we assess parameter values from multiple linear regression. These complementary analyses are performed for each flight date in 2013-2016 at resolutions between 3 and 500m. They are performed globally and for each of the 13 HUC12-level watersheds within the study area. Feature importance and parameter values are compared across features and across intra-seasonal, inter-seasonal, spatial, and model scale dimensions. Initial results demonstrate a consistent pattern to the changing influence of topographic and vegetative features over intra-annual timescales. They support previous findings that elevational gradients dominate local topographic and vegetative features in controlling both depth and SWE yet suggest a declining importance of elevation in the ablation period. Together, topographic and vegetative features explain more of the spatial distribution of depth and SWE observed during

  17. Monitoring and Modeling the Fate and Transport of Nitrate in the Vadose Zone beneath a Suwannee River Basin Vegetable Farm (United States)

    Albert, M. A.; Graham, W. D.; Graetz, D.


    The Suwannee River basin has received much attention in recent years due to increased nitrogen levels in the groundwater-fed rivers of the basin that could seriously affect the welfare of this ecosystem. Nitrogen levels have increased from 0.1mg/l NO3-N to more than 5 mg/L NO3-N in many springs in the Suwannee Basin over the past 40 years. Nitrate concentrations in the Suwannee River itself have been increasing at the rate of .02 mg/L per year over the past 20 years. Suwannee River nitrate loads increase from 2300 kg/day to 6000 kg/day over a 33 mile stretch of the river between Dowling Park and Branford, Florida. Within this stretch of river, 89% of the nitrate loading appeared to come from the lower two-thirds, where agriculture is the dominant land use. The objective of this research is to monitor and model the impacts of alternative nutrient and water management practices on soil water quality, groundwater quality and crop yield at a commercial vegetable farm in the Suwannee River Basin. Groundwater monitoring wells, suction lysimeters, soil cores and TDR probes are used to monitor water and nitrogen transport at the site. Periodic plant biomass sampling is conducted to determine nitrogen uptake by the plants and to estimate crop yield. Field data show that two-thirds of the nitrogen applied to the spring 2001 potato crop leached to groundwater due to excessive irrigation and poor nitrogen uptake efficiency by the potatoes. The DSSAT35-Potato Crop model and the LEACHM vadose-zone model were calibrated for the spring 2001 potato crop and used to predict nitrogen leaching and crop yield for alternative management practices. Simulation results show that by reducing the duration of irrigation, reducing the fertilizer application rate, and improving the timing of fertilizer applications, nitrogen leaching can be reduced by approximately 50% while maintaining acceptable crop yields. Results of this project will ultimately be used to develop best management practices

  18. Application of numerical model simulations for estimation of morphdynamics and vegetation impact on transport of dissolved substances in the Warta river reach

    Directory of Open Access Journals (Sweden)

    Joanna Wicher-Dysarz


    Full Text Available The main problem analysed in this paper is the impact of sediment accumulation and vegetation growth on transport of dissolved substances in a river. The system studied is the reach of the Warta River located upstream of the Jeziorsko Reservoir inlet. The three processes, namely sediment deposition, vegetation growth, and pollutant transport, are crucial for the functionality of reservoir. Classical HEC-RAS package is used for the reconstruction of steady flow conditions in the river reach. The transport of admixture is simulated by means of convection – dispersion model with additional elements describing storage of solutes in the floodplains. The results that the degree of maximum concentration decreases as the river bed geometry and vegetation cover are changed.

  19. Hydrology, vegetation, and soils of four north Florida River flood plains with an evaluation of state and federal wetland determinations (United States)

    Light, H.M.; Darst, M.R.; MacLaughlin, M.T.; Sprecher, S.W.


    A study of hydrologic conditions, vegetation, and soils was made in wetland forests of four north Florida streams from 1987 to 1990. The study was conducted by the U.S. Geological Survey in cooperation with the Florida Department of Environmental Regulation to support State and Federal efforts to improve wetland delineation methodology in flood plains. Plant communities and soils were described and related to topographic position and long-term hydrologic conditions at 10 study plots located on 4 streams. Detailed appendixes give average duration, frequency, and depth of flooding; canopy, subcanopy, and ground-cover vegetation; and taxonomic classification, series, and profile descriptions of soils for each plot. Topographic relief, range in stage, and depth of flooding were greatest on the alluvial flood plain of the Ochlockonee River, the largest of the four streams. Soils were silty in the lower elevations of the flood plain, and tree communities were distinctly different in each topographic zone. The Aucilla River flood plain was dominated by levees and terraces with very few depressions or low backwater areas. Oaks dominated the canopy of both lower and upper terraces of the Aucilla flood plain. Telogia Creek is a blackwater stream that is a major tributary of the Ochlockonee River. Its low, wet flood plain was dominated by Wyssa ogeche (Ogeechee tupelo) trees, had soils with mucky horizons, and was inundated by frequent floods of very short duration. The St. Marks River, a spring-fed stream with high base flow, had the least topographic relief and lowest range in stage of the four streams. St. Marks soils had a higher clay content than the other streams, and limestone bedrock was relatively close to the surface. Wetland determinations of the study plots based on State and Federal regulatory criteria were evaluated. Most State and Federal wetland determinations are based primarily on vegetation and soil characteristics because hydrologic records are usually not

  20. 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)

    LaGory, K.E.; Van Lonkhuyzen, R.A.


    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

  1. Contamination with Cadmium and Arsenic in soils and vegetables of a sector of the Bogota River Basin

    International Nuclear Information System (INIS)

    Gonzalez G, Saul; Mejia, Leonidas


    Soils of six different horticultural sites of the Savanna of Bogota (Cundinamarca) traditionally watered with the highly polluted waters of the Bogota River, were sampled to quantify Cd and As accumulated with irrigation. Soil of site six representatives of Rio Bogota series (fine clay, mixed, isothermic family of Fluventic tropaquepts) was selected for greenhouse experiments directed to show: a) Actual content of Cd and As in one of the most representative horticultural soil sites of the plain savanna. b) The accumulation level of Cd and As in the edible parts of three different vegetables (lettuce, cucumber and carrots) watered with polluted waters with know and variable Cd and As concentrations. c) The effects of Cd and As on vegetable's yields

  2. 76 FR 2878 - Six Rivers National Forest, Mad River Ranger District, CA; Buck Mountain Vegetation and Fuel... (United States)


    ... with high fuel loadings. (2) The majority of the planning area occurs within the Wildland Urban... extend the availability of forage and reduce the rate of spread of wildfire. (4) The Van Duzen River... cutting, mastication, road-side chipping, prescribed fire, hand piling, biomass/fuelwood utilization...

  3. The distribution of submersed aquatic vegetation and water lettuce in the fresh and oligohaline tidal Potomac River, 2007 (United States)

    Campbell, Sarah Hunter; Rybicki, Nancy B.; Schenk, Edward R.


    Surveys documenting the composition of species of submersed aquatic vegetation (SAV) have been conducted in the Potomac River for decades. These surveys can help managers assess the proportion of native and exotic plants in the river or can be used to determine relationships between native and exotic plants, environmental conditions, and wildlife. SAV coverage increased from 2005 to 2007 throughout the fresh and oligohaline study area. The 2007 survey documented here determined that eleven species of SAV were present. The abundance of the exotic species Hydrilla verticillata (hydrilla) was relatively low, and species diversity was relatively high compared to previous years. The survey also revealed a new population of the invasive, floating aquatic plant Pistia stratiotes (water lettuce). In 2007, water lettuce, the latest exotic aquatic plant to be found in the fresh to oligohaline portion of the Potomac River, was most abundant in Mattawoman Creek, Charles County, Maryland. However, it was not observed in the fresh to oligohaline portion of the Potomac River in the summer of 2008. An understanding of the distribution of SAV species and factors governing the abundance of native and invasive aquatic species is enhanced by long-term surveys.

  4. Vegetation dynamic characteristics and its responses to climate change in Jinghe River watershed of Loess Plateau, China (United States)

    Chang, F.; Liu, W.; Zhou, H.; Ning, T.; Wang, Y.


    The Jinghe River is a second-order tributary of the Yellow River, and located in the middle-south part of the Loess Plateau. The watershed area is 45421km², with the mean annual precipitation (P) being about 508mm and aridity index 2.09. For a long time, soil and water loss in this watershed is severe, resulting in very fragile ecological environment. The GIMMS-normalized vegetation index NDVI is used to reflect condition of vegetation cover, and P and Penman potential evapotranspiration (ET) to represent climate water and heat conditions. The annual actual ET is estimated as the difference between P and runoff (ignoring the change of watershed water storage during each hydrological year, May to April of the following year). These concepts were introduced to discuss the dynamic characteristics of vegetation cover and its response to climate change. Results showed that the mean annual NDVI value was 0.51, showing a stable increasing trend from 2000 with an annual increasing rate of 8.7×10¯³. This result is consistent with the implementation of the project that converts farmland to forests and grassland and has achieved remarkable success in the Loess Plateau since 1999. It also indicates that the positive impact of human activity has been strengthened under the background of climate change. From 1982 to 2012, the annual actual ET was 464mm, accounting for 93.6% of annual P over the same period. The NDVI value of main growing season (5-9 months) is significantly correlated with annual P and annual humid index (ratio of annual P to annual potential ET). Vegetation water consumption is the main part of land surface ET, and the relationship between annual actual ET and NDVI value over the same period is also significant. The NDVI value, P and potential ET variation varied substantially within the Jinghe River watershed, and their relationships in different regions at an inter-annual scale are different. Currently, we are investigating the influence of the changes in

  5. Monitoring riparian-vegetation composition and cover along the Colorado River downstream of Glen Canyon Dam, Arizona (United States)

    Palmquist, Emily C.; Ralston, Barbara E.; Sarr, Daniel A.; Johnson, Taylor C.


    Vegetation in the riparian zone (the area immediately adjacent to streams, such as stream banks) along the Colorado River downstream of Glen Canyon Dam, Arizona, supports many ecosystem and societal functions. In both Glen Canyon and Grand Canyon, this ecosystem has changed over time in response to flow alterations, invasive species, and recreational use. Riparian-vegetation cover and composition are likely to continue to change as these pressures persist and new ones emerge. Because this system is a valuable resource that is known to change in response to flow regime and other disturbances, a long-term monitoring protocol has been designed with three primary objectives:Annually measure and summarize the status (composition and cover) of native and non-native vascular-plant species within the riparian zone of the Colorado River between Glen Canyon Dam and Lake Mead.At 5-year intervals, assess change in vegetation composition and cover in the riparian zone, as related to geomorphic setting and dam operations, particularly flow regime.Collect data in a manner that can be used by multiple stakeholders, particularly the basinwide monitoring program overseen by the National Park Service’s Northern Colorado Plateau Network Inventory and Monitoring program.A protocol for the long-term monitoring of riparian vegetation is described in detail and standard operating procedures are included herein for all tasks. Visual estimates of foliar and ground covers are collected in conjunction with environmental measurements to assess correlations of foliar cover with abiotic and flow variables. Sample quadrats are stratified by frequency of inundation, geomorphic feature, and by river segment to account for differences in vegetation type. Photographs of sites are also taken to illustrate qualitative characteristics of the site at the time of sampling. Procedures for field preparation, generating random samples, data collection, data management, collecting and managing unknown

  6. Hydraulic Balance, under three contrasting vegetable coverings in the San Cristobal River basin, Bogota

    International Nuclear Information System (INIS)

    De las salas, Gonzalo; Garcia Olmos, Carlos


    A hydrological balance fewer than three forest covers in the San Cristobal river watershed was done. Records of precipitation during one year under each canopy were registered along with measurements on the river stream of three micro watersheds adjacent to the forest canopies. The following parameters were evaluated: evapotranspiration, trough fall, interception, infiltration and water storage, which are discussed critically

  7. Assessment of Vegetation Density and Soil Macrofauna Relationship in Riparian Forest of Karkhe River for the Determination of Rivers Buffer Zone

    Directory of Open Access Journals (Sweden)

    SH. Gholami


    Full Text Available The spatial distribution of soil organisms is influenced by the plant cover, thus resulting in a horizontal mosaic of areas subjected to gradients of nutrient availability and microclimatic conditions.This study was conducted to investigate the spatial variability of soil macrofauna in relation to vegetation density in the riparian forest landscape of Karkhe. The vegetation density was determined by calculating the NDVI index. Soil macrofauna were sampled using 200 sampling points along parallel transects (perpendicular to the river. The maximum distance between samples was 0.5 km. Soil macrofauna were extracted from 50 cm×50 cm×25 cm soil monolith by the hand-sorting procedure. Abundance, diversity (Shannon H’ index, richness (Menhinick index and evenness (Sheldon index were calculated. Soil macrofauna and NDVI data were analyzed using geostatistics (variogram in order to describe and quantify the spatial continuity. The variograms were spherical, revealing the presence of spatial autocorrelation. The range of influence was 1724 m for abundance, 1326 m for diversity, 1825 m for richness, 1450 for evenness and 1977 m for NDVI. The kriging maps showed that the NDVI Index and soil macrofauna had spatial variability. The spatial pattern of soil macrofauna abundance and biodiversity were similar to the spatial pattern of vegetation density as shown in the correlation.

  8. Influence of agricultural practice on trace metals in soils and vegetation in the water conservation area along the East River (Dongjiang River), South China

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chunling, E-mail: [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Yang, Renxiu [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Wang, Yan; Li, Jun; Zhang, Gan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li, Xiangdong [Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)


    Dongjiang (East River) is the key resource of potable water for the Pearl River Delta region, South China. Although industrial activities are limited in the water conservation area along this river, agriculture is very intensive. The present study evaluated trace metals in four soils under different cultivation. The total concentrations of trace metals decreased in the order orchard soil > vegetable soil > paddy soil > natural soil, reflecting decreasing inputs of agrochemicals to soils. Relatively high concentrations of Cd were recorded in the 60-cm soil profiles. The {sup 206}Pb/{sup 207}Pb ratio in the above-ground tissues of plant was significantly lower than their corresponding soils. In combination with the low transfer factor of Pb from soil to plant shoots, atmospheric deposition is probably a major pathway for Pb to enter plant leaves. Regular monitoring on the soil quality in this area is recommended for the safety of water resource and agricultural products. - Highlights: Black-Right-Pointing-Pointer Soil Cd exceeded the upper limit of Chinese standard for agricultural soils. Black-Right-Pointing-Pointer Relatively high concentrations of Cd were recorded in the 60-cm soil profiles. Black-Right-Pointing-Pointer Agricultural soil had higher concentrations of metals and lower {sup 206}Pb/{sup 207}Pb ratios. Black-Right-Pointing-Pointer Pb in above-ground tissues of plant was more anthropogenic than soil. Black-Right-Pointing-Pointer Atmospheric deposition may be a major pathway for Pb to enter plant leaves.


    Directory of Open Access Journals (Sweden)

    M. Broich


    Full Text Available Australia is a continent subject to high rainfall variability, which has major influences on runoff and vegetation dynamics. However, the resulting spatial-temporal pattern of flooding and its influence on riparian vegetation has not been quantified in a spatially explicit way. Here we focused on the floodplains of the entire Murray-Darling Basin (MDB, an area that covers over 1M km2, as a case study. The MDB is the country’s primary agricultural area with scarce water resources subject to competing demands and impacted by climate change and more recently by the Millennium Drought (1999–2009. Riparian vegetation in the MDB floodplain suffered extensive decline providing a dramatic degradation of riparian vegetation. We quantified the spatial-temporal impact of rainfall, temperature and flooding patters on vegetation dynamics at the subcontinental to local scales and across inter to intra-annual time scales based on three decades of Landsat (25k images, Bureau of Meteorology data and one decade of MODIS data. Vegetation response varied in space and time and with vegetation types, densities and location relative to areas frequently flooded. Vegetation degradation trends were observed over riparian forests and woodlands in areas where flooding regimes have changed to less frequent and smaller inundation extents. Conversely, herbaceous vegetation phenology followed primarily a ‘boom’ and ‘bust’ cycle, related to inter-annual rainfall variability. Spatial patters of vegetation degradation changed along the N-S rainfall gradient but flooding regimes and vegetation degradation patterns also varied at finer scale, highlighting the importance of a spatially explicit, internally consistent analysis and setting the stage for investigating further cross-scale relationships. Results are of interest for land and water management decisions. The approach developed here can be applied to other areas globally such as the Nile river basin and

  10. Influence of urbanization on the original vegetation cover in urban river basin: case study in Campinas/SP, Brazil (United States)

    Leite Silva, Alessandra; Márcia Longo, Regina


    ABSTRACT: In most Brazilian municipalities, urban development was not based on adequate planning; one of the consequences was the reduction of the original vegetation, limiting the forest formations to scarce and isolated fragments. In Campinas, São Paulo, Brazil, the vegetation fragmentation was mainly related to the expeditions and to the cycles of sugar cane and coffee. In this way, the present study aims to identify, quantify and evaluate the remaining arboreal vegetation spatial distribution in the Anhumas River Basin - Campinas/SP, Brazil. This study was developed with the aid of GIS software and field visits in order to construct a diagnosis of these areas and subsidize future actions required and to discuss the influence of urbanization on the original vegetation cover. The area was initially occupied by the Atlantic Forest (semi-deciduous forest) and drains one of the oldest urban occupation areas in the municipality; according to researchers, based on the water and geomorphological conditions of the basin, it can be subdivided into high, medium and low course. With a total area of 156,514 km2, only 16.74% are classified as green areas; where just 1.07% and 6.17% of total area represents forests and reforestation areas, respectively. The remaining green areas consists of: wetlands close to water bodies, but with no presence of trees and shrubs (area of 0.12% of the basin); urban green space, including parks and squares (2.19%); and natural field, constituted by natural non-arboreous vegetation (7.18%). In a scenario like this, a characteristic situation is the forest fragmentation; this process results in native vegetation remnants, isolated and more susceptible to external interference, coming from, for example, the proximity to agricultural areas or others land uses. The ecological knowledge of the remnants and their correct management can not only make it possible to diagnose current problems and to estimate future influences, but also to point out the

  11. Soil erosion and sediment yield and their relationships with vegetation cover in upper stream of the Yellow River. (United States)

    Ouyang, Wei; Hao, Fanghua; Skidmore, Andrew K; Toxopeus, A G


    Soil erosion is a significant concern when considering regional environmental protection, especially in the Yellow River Basin in China. This study evaluated the temporal-spatial interaction of land cover status with soil erosion characteristics in the Longliu Catchment of China, using the Soil and Water Assessment Tool (SWAT) model. SWAT is a physical hydrological model which uses the RUSLE equation as a sediment algorithm. Considering the spatial and temporal scale of the relationship between soil erosion and sediment yield, simulations were undertaken at monthly and annual temporal scales and basin and sub-basin spatial scales. The corresponding temporal and spatial Normalized Difference Vegetation Index (NDVI) information was summarized from MODIS data, which can integrate regional land cover and climatic features. The SWAT simulation revealed that the annual soil erosion and sediment yield showed similar spatial distribution patterns, but the monthly variation fluctuated significantly. The monthly basin soil erosion varied from almost no erosion load to 3.92 t/ha and the maximum monthly sediment yield was 47,540 tones. The inter-annual simulation focused on the spatial difference and relationship with the corresponding vegetation NDVI value for every sub-basin. It is concluded that, for this continental monsoon climate basin, the higher NDVI vegetation zones prevented sediment transport, but at the same time they also contributed considerable soil erosion. The monthly basin soil erosion and sediment yield both correlated with NDVI, and the determination coefficients of their exponential correlation model were 0.446 and 0.426, respectively. The relationships between soil erosion and sediment yield with vegetation NDVI indicated that the vegetation status has a significant impact on sediment formation and transport. The findings can be used to develop soil erosion conservation programs for the study area. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Short-term vegetation response following mechanical control of saltcedar (Tamarix spp.) on the Virgin River, Nevada, USA (United States)

    Ostoja, Steven M.; Brooks, Matthew L.; Dudley, Tom; Lee, Steven R.


    Tamarisk (a.k.a. saltcedar, Tamarix spp.) is an invasive plant species that occurs throughout western riparian and wetland ecosystems. It is implicated in alterations of ecosystem structure and function and is the subject of many local control projects, including removal using heavy equipment. We evaluated short-term vegetation responses to mechanical Tamarix spp. removal at sites ranging from 2 to 5 yr post-treatment along the Virgin River in Nevada, USA. Treatments resulted in lower density and cover (but not eradication) of Tamarix spp., increased cover of the native shrub Pluchea sericia (arrow weed), decreased density and cover of all woody species combined, increased density of both native annual forbs and the nonnative annual Salsola tragus (prickly Russian-thistle), and lower density of nonnative annual grasses. The treated plots had lower mean woody species richness, but greater herbaceous species richness and diversity. Among herbaceous species, native taxa increased in richness whereas nonnative species increased in both species richness and diversity. Thus, efforts to remove Tamarix,/i> spp. at the Virgin River reduced vegetative cover contributing to fuel loads and probability of fire, and resulted in positive effects for native plant diversity, with mixed effects on other nonnative species. However, absolute abundances of native species

  13. Salmonids, stream temperatures, and solar loading--modeling the shade provided to the Klamath River by vegetation and geomorphology (United States)

    Forney, William M.; Soulard, Christopher E.; Chickadel, C. Christopher


    The U.S. Geological Survey is studying approaches to characterize the thermal regulation of water and the dynamics of cold water refugia. High temperatures have physiological impacts on anadromous fish species. Factors affecting the presence, variability, and quality of thermal refugia are known, such as riverine and watershed processes, hyporheic flows, deep pools and bathymetric factors, thermal stratification of reservoirs, and other broader climatic considerations. This research develops a conceptual model and methodological techniques to quantify the change in solar insolation load to the Klamath River caused by riparian and floodplain vegetation, the morphology of the river, and the orientation and topographic characteristics of its watersheds. Using multiple scales of input data from digital elevation models and airborne light detection and ranging (LiDAR) derivatives, different analysis methods yielded three different model results. These models are correlated with thermal infrared imagery for ground-truth information at the focal confluence with the Scott River. Results from nonparametric correlation tests, geostatistical cross-covariograms, and cross-correlograms indicate that statistical relationships between the insolation models and the thermal infrared imagery exist and are significant. Furthermore, the use of geostatistics provides insights to the spatial structure of the relationships that would not be apparent otherwise. To incorporate a more complete representation of the temperature dynamics in the river system, other variables including the factors mentioned above, and their influence on solar loading, are discussed. With similar datasets, these methods could be applied to any river in the United States—especially those listed as temperature impaired under Section 303(d) of the Clean Water Act—or international riverine systems. Considering the importance of thermal refugia for aquatic species, these methods can help investigate opportunities

  14. Vegetation Patchiness Enhances Hydrological Connectivity in River Deltas Below the Percolation Threshold (United States)

    Wright, K. A.; Hiatt, M. R.; Passalacqua, P.


    The humanitarian and ecological importance of coastal deltas has led many to research the factors influencing their ecogeomorphic evolution, in hopes of predicting the response of these regions to the growing number of natural and anthropogenic threats they face. One area of this effort, in which many unresolved questions remain, concerns the hydrological connectivity between the distributary channels and interdistributary islands, which field observations and numerical modeling have shown to be significant. Island vegetation is known to affect the degree of connectivity, but the effect of the spatial distribution of vegetation on connectivity remains an important question. This research aims to determine to what extent vegetation percent cover, patch size, and plant density affect connectivity in an idealized deltaic system. A 2D hydrodynamic model was used to numerically solve the shallow water equations in an idealized channel-island complex, modeled after Wax Lake Delta in Louisiana. For each model run, vegetation patches were distributed randomly throughout the islands according to a specified percent cover and patch size. Vegetation was modeled as a modified bed roughness, which was varied to represent a range of sparse-to-dense vegetation. To determine the effect of heterogeneity, the results of each patchy scenario were compared to results from a uniform run with the same spatially-averaged roughness. It was found that, while all patchy model runs demonstrated more channel-island connectivity than comparable uniform runs, this was particularly true when vegetation patches were dense and covered distributions in the deltaic islands, which can have implications for the fate and transport of sediment/nutrients. These results indicate that the spatial distribution of vegetation can have a notable impact on our ability to model connectivity in deltaic systems.

  15. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geoform (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  16. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Geodatabase (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  17. Benthic Habitat Mapping - Indian River Lagoon, Florida Submerged Aquatic Vegetation (SAV) Data 1996 Substrate (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Office for Coastal Management's Coastal Change Analysis Program, in cooperation with the St. Johns River and South Florida Water Management Districts, used...

  18. Predicted riparian vegetation - Potential for Habitat Improvement in the Columbia River Basin (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Basin-wide analysis of potential to improve tributary habitats in the Columbia River basin through restoration of habitat-forming processes. Identification of...

  19. Floodplain Vegetation Dynamics Modeling Using Coupled RiPCAS-DFLOW (CoRD): Jemez Canyon, Jemez River, New Mexico (United States)

    Miller, S. J.; Gregory, A. E.; Turner, M. A.; Chaulagain, S.; Cadol, D.; Stone, M. C.; Sheneman, L.


    Interactions among precipitation, vegetation, soil moisture, runoff and other landscape properties set the stage for complex streamflow regimes and cascading riparian habitat impacts, particularly in semi-arid regions. A consortium of New Mexico, Nevada, and Idaho, funded through NSF-EPSCoR, has promulgated the Western Consortium for Watershed Analysis, Visualization, and Exploration (WC-WAVE). Two WC-WAVE objectives are to advance understanding of hydrologic interactions and ecosystem services, and to develop a virtual watershed platform (VWP) cyber-infrastructure to unite and streamline coordination among teams, databases and modeling tools. To provide proof of concept for the VWP and to study coevolution of riparian habitat mosaics and flood dynamics, the study team selected two models and developed a model coupling system for the Jemez River Canyon, Jemez River, NM. DFLOW is a 2-D hydrodynamic model for steady and unsteady flow conditions; the Riparian Community Alteration and Succession (RipCAS) model, developed using concepts from a vegetation disturbance and succession model (CASiMiR), uses shear stresses and flood depths from DFLOW to evolve riparian vegetation maps with associated roughness. The Coupled RipCAS-DFLOW (CoRD) model allows serial annual time step feedback of changes in peak-flow-derived depth and shear stress and vegetation-derived roughness values. An intuitive command-line interface on a computing cluster is used to call CoRD, which provides commands to calculate boundary conditions, perform multiple file and data format conversions and archive and compress decades of data. Four thirty-year synthetic annual maximum flood scenarios were selected for CoRD simulations, representing a historical wet period (1957-1986) a historical dry period (1986-2015), and flows doubling the historical wet period and halving the historical dry period. Event-driven coupled modeling simulates the spatial distribution of floodplain vegetation community evolution


    Directory of Open Access Journals (Sweden)



    Full Text Available The longitudinal changes of richness and composition of aquatic plants have been studied from headwaters to the fifth stream order in three near-by rivers or Western Brittany (France, the Orne, Sélune and Rance. All rivers were regulated years ago with dams located on the lower third of the studies river stretches. A shifting evolution of the macrophyte richness was revealed in a previous study along the river continuum, related 10 habitat heterogeneity. influences of regulated sectors and geological changes. Nutrient enrichment and organic pollution influences were the main secondary gradients. On this basis we improved a methodology to complete a biotic index used in Europe for water trophy assessment, following the European water frame work directive the IBMR based on aquatic plant survey: a validation with classical statistical tests and a comparison to a canonical analysis were performed. Finally this approach permitted to make a proposition of adaptation of the index to the Local particularities of each three high anthropised rivers


    Directory of Open Access Journals (Sweden)



    Full Text Available The longitudinal changes of richness and composition of aquatic plants have been studied from headwaters to the fifth stream order in three near-by rivers or Western Brittany (France, the Orne, Sélune and Rance. All rivers were regulated years ago with dams located on the lower third of the studies river stretches. A shifting evolution of the macrophyte richness was revealed in a previous study along the river continuum, related 10 habitat heterogeneity. influences of regulated sectors and geological changes. Nutrient enrichment and organic pollution influences were the main secondary gradients. On this basis we improved a methodology to complete a biotic index used in Europe for water trophy assessment, following the European water frame work directive the IBMR based on aquatic plant survey: a validation with classical statistical tests and a comparison to a canonical analysis were performed. Finally this approach permitted to make a proposition of adaptation of the index to the Local particularities of each three high anthropised rivers

  2. A Vegetation Database for the Colorado River Ecosystem from Glen Canyon Dam to the Western Boundary of Grand Canyon National Park, Arizona (United States)

    Ralston, Barbara E.; Davis, Philip A.; Weber, Robert M.; Rundall, Jill M.


    A vegetation database of the riparian vegetation located within the Colorado River ecosystem (CRE), a subsection of the Colorado River between Glen Canyon Dam and the western boundary of Grand Canyon National Park, was constructed using four-band image mosaics acquired in May 2002. A digital line scanner was flown over the Colorado River corridor in Arizona by ISTAR Americas, using a Leica ADS-40 digital camera to acquire a digital surface model and four-band image mosaics (blue, green, red, and near-infrared) for vegetation mapping. The primary objective of this mapping project was to develop a digital inventory map of vegetation to enable patch- and landscape-scale change detection, and to establish randomized sampling points for ground surveys of terrestrial fauna (principally, but not exclusively, birds). The vegetation base map was constructed through a combination of ground surveys to identify vegetation classes, image processing, and automated supervised classification procedures. Analysis of the imagery and subsequent supervised classification involved multiple steps to evaluate band quality, band ratios, and vegetation texture and density. Identification of vegetation classes involved collection of cover data throughout the river corridor and subsequent analysis using two-way indicator species analysis (TWINSPAN). Vegetation was classified into six vegetation classes, following the National Vegetation Classification Standard, based on cover dominance. This analysis indicated that total area covered by all vegetation within the CRE was 3,346 ha. Considering the six vegetation classes, the sparse shrub (SS) class accounted for the greatest amount of vegetation (627 ha) followed by Pluchea (PLSE) and Tamarix (TARA) at 494 and 366 ha, respectively. The wetland (WTLD) and Prosopis-Acacia (PRGL) classes both had similar areal cover values (227 and 213 ha, respectively). Baccharis-Salix (BAXX) was the least represented at 94 ha. Accuracy assessment of the

  3. Woody vegetation of the Upper Verde River: 1996-2007 [Chapter 6 (United States)

    Alvin L. Medina


    Streamside vegetation is an integral component of a stable riparian ecosystem, providing benefits to both terrestrial and aquatic fauna (Brown and others 1977; National Research Council 2002) as well as Native Americans (Betancourt and Van Devender 1981). On the UVR, stable streambanks are a desirable management goal to attain channel stability for a variety of...


    The extent of aquatic off-channel habitats such as secondary and side channels, sloughs, and alcoves, have been reduced more than 50% since the 1850s along the upper main stem of the Willamette River, Oregon, USA. Concurrently, the hydrogeomorphic potential, and associated flood...

  5. Hydrology, geomorphology, and vegetation of Coastal Plain rivers in the southeastern United States (United States)

    Cliff R. Hupp


    Rivers of the Coastal Plain of the southeastern United States are characteristically low-gradient meandering systems that develop broad floodplains subjected to frequent and prolonged flooding. These floodplains support a relatively unique forested wetland (Bottomland Hardwoods), which have received considerable ecological study, but distinctly less hydrogeomorphic...

  6. Arboreous vegetation of an alluvial riparian forest and their soil relations: Porto Rico island, Paraná river, Brazil

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    Campos João Batista


    Full Text Available The dynamics of alluvial deposits in floodplains forms islands and sandbanks. Deposits frequently accumulate at the river margins and on islands with consequent side growths. One of these sandbanks which started to form in 1952 annexed an area of 12.4ha to the Porto Rico island (53masculine15?W and 22masculine45?S. At present a forest fragment of approximately 2.0 ha exists in this place. The structural analysis of arboreous vegetation of this fragment showed a floristic gradient related to the physical and chemical variations of the substratum. High density of pioneer species associated to the absence of recruitment of new individuals of these and other successional categories indicated that the forest was impaired in its succession process. This fact could be associated with constant disturbances caused by cattle in the area.

  7. Structure and Composition of Vegetation of Longleaf Pine Plantations Compared to Natural Stands Occurring Along an Environmental Gradient at the Savannah River Site (United States)

    Gregory P. Smith; Victor B. Shelburne; Joan L. Walker


    Fifty-four plots in 33-43 year old longleaf pine plantations were compared to 30 remnant plots in longleaf stands on the Savannah River Site in South Carolina. Within these stands, the structure and composition of primarily the herb layer relative to a presumed soil moisture or soil texture gradient was studied using the North Carolina Vegetation Survey methodology....

  8. Can riparian vegetation shade mitigate the expected rise in stream temperatures due to climate change during heat waves in a human-impacted pre-alpine river?

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    H. Trimmel


    Full Text Available Global warming has already affected European rivers and their aquatic biota, and climate models predict an increase of temperature in central Europe over all seasons. We simulated the influence of expected changes in heat wave intensity during the 21st century on water temperatures of a heavily impacted pre-alpine Austrian river and analysed future mitigating effects of riparian vegetation shade on radiant and turbulent energy fluxes using the deterministic Heat Source model. Modelled stream water temperature increased less than 1.5 °C within the first half of the century. Until 2100, a more significant increase of around 3 °C in minimum, maximum and mean stream temperatures was predicted for a 20-year return period heat event. The result showed clearly that in a highly altered river system riparian vegetation was not able to fully mitigate the predicted temperature rise caused by climate change but would be able to reduce water temperature by 1 to 2 °C. The removal of riparian vegetation amplified stream temperature increases. Maximum stream temperatures could increase by more than 4 °C even in annual heat events. Such a dramatic water temperature shift of some degrees, especially in summer, would indicate a total shift of aquatic biodiversity. The results demonstrate that effective river restoration and mitigation require re-establishing riparian vegetation and emphasize the importance of land–water interfaces and their ecological functioning in aquatic environments.

  9. Can riparian vegetation shade mitigate the expected rise in stream temperatures due to climate change during heat waves in a human-impacted pre-alpine river? (United States)

    Trimmel, Heidelinde; Weihs, Philipp; Leidinger, David; Formayer, Herbert; Kalny, Gerda; Melcher, Andreas


    Global warming has already affected European rivers and their aquatic biota, and climate models predict an increase of temperature in central Europe over all seasons. We simulated the influence of expected changes in heat wave intensity during the 21st century on water temperatures of a heavily impacted pre-alpine Austrian river and analysed future mitigating effects of riparian vegetation shade on radiant and turbulent energy fluxes using the deterministic Heat Source model. Modelled stream water temperature increased less than 1.5 °C within the first half of the century. Until 2100, a more significant increase of around 3 °C in minimum, maximum and mean stream temperatures was predicted for a 20-year return period heat event. The result showed clearly that in a highly altered river system riparian vegetation was not able to fully mitigate the predicted temperature rise caused by climate change but would be able to reduce water temperature by 1 to 2 °C. The removal of riparian vegetation amplified stream temperature increases. Maximum stream temperatures could increase by more than 4 °C even in annual heat events. Such a dramatic water temperature shift of some degrees, especially in summer, would indicate a total shift of aquatic biodiversity. The results demonstrate that effective river restoration and mitigation require re-establishing riparian vegetation and emphasize the importance of land-water interfaces and their ecological functioning in aquatic environments.

  10. Wind tunnel experiments of air flow patterns over nabkhas modeled after those from the Hotan River basin,Xinjiang,China(Ⅱ):vegetated

    Institute of Scientific and Technical Information of China (English)

    Zhizhong LI; Rong MA; ShengLi WU; Janis DALE; Lin GE; Mudan HE; Xiaofeng WANG; Jianhui JIN; Jinwei LIU; Wanjuan LI


    This paper examines the results of wind tunnel experiments on models of nabkha,based on those studied in the Hotan River basin.Semi-spherical and conical models of nabkhas were constructed at a ratio of 40:1 in light of the on-site observation.Artificial vegetation of simulated Tamarix spp.was put on top of each model.Parameters of the shape,including height,width,and diameter of vegetated semi-spherical and conical nabkha.were measured in the Hotan River basin.Wind tunnel experiments on the semi-spherical and conical nabkha used clean air devoid of additional sediments at five different wind speeds (6-14 m/s)to study the influence of vegetation on airflow patterns.Results of the experiments indicate that vegetation at the top of the nabkhas enhances the surface roughness of the sand mounds,retards airflow over the sand mounds,reduces airflow energy,eliminates erosional pits occurring on the top surface of non-vegetated sand mounds and enhances the range of influence of the vortex that forms on the leeward slope.Vegetation changes the airflow pattern upwind and downwind of the sand mound and reduces the transport of sand away from the nabkha.This entrapment of sediment by the vegetation plays an important role in sustaining the nabkha landscape of the study area.The existence of vegetation makes fine materials in wind-sand flow to possibly deposit,and promotes nabkha formation.The imitative flow patterns Of different morphological nabkhas have also been verified by on-site observation in the river basin.

  11. Response characteristics of vegetation and soil environment to permafrost degradation in the upstream regions of the Shule River Basin

    International Nuclear Information System (INIS)

    Chen Shengyun; Liu Wenjie; Qin Xiang; Liu Yushuo; Ren Jiawen; Qin Dahe; Zhang Tongzuo; Hu Fengzu; Chen Kelong


    Permafrost degradation exhibits striking and profound influences on the alpine ecosystem, and response characteristics of vegetation and soil environment to such degradation inevitably differ during the entire degraded periods. However, up to now, the related research is lacking in the Qinghai–Tibetan Plateau (QTP). For this reason, twenty ecological plots in the different types of permafrost zones were selected in the upstream regions of the Shule River Basin on the northeastern margin of the QTP. Vegetation characteristics (species diversity, community coverage and biomass etc) and topsoil environment (temperature (ST), water content (SW), mechanical composition (SMC), culturable microorganism (SCM), organic carbon (SOC) and total nitrogen (TN) contents and so on), as well as active layer thickness (ALT) were investigated in late July 2009 and 2010. A spatial–temporal shifts method (the spatial pattern that is represented by different types of permafrost shifting to the temporal series that stands for different stages of permafrost degradation) has been used to discuss response characteristics of vegetation and topsoil environment throughout the entire permafrost degradation. The results showed that (1) ST of 0–40 cm depth and ALT gradually increased from highly stable and stable permafrost (H-SP) to unstable permafrost (UP). SW increased initially and then decreased, and SOC content and the quantities of SCM at a depth of 0–20 cm first decreased and then increased, whereas TN content and SMC showed obscure trends throughout the stages of permafrost degradation with a stability decline from H-SP to extremely unstable permafrost (EUP); (2) further, species diversity, community coverage and biomass first increased and then decreased in the stages from H-SP to EUP; (3) in the alpine meadow ecosystem, SOC and TN contents increased initially and then decreased, soil sandy fractions gradually increased with stages of permafrost degradation from substable (SSP

  12. [Relationships among leaf traits and their expression in different vegetation zones in Yanhe River basin, Northwest China]. (United States)

    Guo, Ru; Wen, Zhong-ming; Wang, Hong-xia; Qi, De-hui


    This article selected zonal plant communities as the research objects in different vegetation zones in Yanhe River basin. We measured six leaf traits of the dominant species and main accompanying species in each community, and then analyzed the relationships and their changes along with environmental gradients between these traits in order to understand the plant adaptation strategies to the environment changes. The results showed that the specific leaf area was significantly negatively correlated to leaf tissue density, area-based leaf nitrogen and phosphorus concentrations, and significantly positively correlated to mass-based leaf phosphorus concentration. Both the scaling relationships among these traits and plant life strategies were different among the three vegetation zones, the scaling-dependent relationship between leaf tissue density and specific leaf area was stronger in steppe and forest-steppe zones than in forest zone, but the correlations among area-based leaf nitrogen/phosphorus concentrations and specific leaf area and leaf tissue density were more significant in forest zone than in steppe zone. In the arid grassland and forest-steppe zone, plants give priority to defensive and stress resistance strategies, and in relatively moist nutrient-rich forest zone, plants give priority to fast growth and resource optimization allocation strategies.

  13. Remote Sensing of Submerged Aquatic Vegetation in a Shallow Non-Turbid River Using an Unmanned Aerial Vehicle

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    Kyle F. Flynn


    Full Text Available A passive method for remote sensing of the nuisance green algae Cladophora glomerata in rivers is presented using an unmanned aerial vehicle (UAV. Included are methods for UAV operation, lens distortion correction, image georeferencing, and spectral analysis to support algal cover mapping. Eighteen aerial photography missions were conducted over the summer of 2013 using an off-the-shelf UAV and three-band, wide-angle, red, green, and blue (RGB digital camera sensor. Images were post-processed, mosaicked, and georeferenced so automated classification and mapping could be completed. An adaptive cosine estimator (ACE and spectral angle mapper (SAM algorithm were used to complete the algal identification. Digital analysis of optical imagery correctly identified filamentous algae and background coverage 90% and 92% of the time, and tau coefficients were 0.82 and 0.84 for ACE and SAM, respectively. Thereafter, algal cover was characterized for a one-kilometer channel segment during each of the 18 UAV flights. Percent cover ranged from <5% to >50%, and increased immediately after vernal freshet, peaked in midsummer, and declined in the fall. Results indicate that optical remote sensing with UAV holds promise for completing spatially precise, and multi-temporal measurements of algae or submerged aquatic vegetation in shallow rivers with low turbidity and good optical transmission.

  14. The role of catchment vegetation in reducing atmospheric inputs of pollutant aerosols in Ganga river. (United States)

    Shubhashish, Kumar; Pandey, Richa; Pandey, Jitendra


    The role of woody perennials in the Ganga river basin in modifying the run-off quality as influenced by atmospheric deposition of pollutant aerosols was investigated. The concentration of seven nutrients and eight metals were measured in atmospheric deposits as well as in run-off water under the influence of five woody perennials. Nutrient retention was recorded maximum for Bougainvillea spectabilis ranged from 4.30 % to 33.70 %. Metal retention was recorded highest for Ficus benghalensis ranged from 5.15 % to 36.98 %. Although some species showed nutrient enrichment, all the species considered in the study invariably contribute to reduce nutrients and metal concentration in run-off water. Reduction in run off was recorded maximum for B. spectabilis (nutrient 6.48 %-40.66 %; metal 7.86 %-22.85 %) and minimum for Ficus religiosa (nutrient 1.68 %-27.19 %; metal 6.55 %-31.55 %). The study forms the first report on the use of woody perennials in reducing input of atmospheric pollutants to Ganga river and has relevance in formulating strategies for river basin management.

  15. Influence of riparian vegetation on near-bank flow structure and erosion rates on a large meandering river (United States)

    Konsoer, K. M.; Rhoads, B. L.; Langendoen, E. J.; Johnson, K.; Ursic, M.


    Rates of meander migration are dependent upon dynamic interactions between planform geometry, three-dimensional flow structure, sediment transport, and the erodibility and geotechnical properties of the channel banks and floodplains. Riparian vegetation can greatly reduce the rate of migration through root-reinforcement and increased flow resistance near the bank. In particular, forested riverbanks can also provide large woody debris (LWD) to the channel, and if located near the outer bank, can act to amour the bank by disrupting three-dimensional flow patterns and redirecting flow away from the bank-toe, the locus of erosion in meandering rivers. In this paper, three-dimensional flow patterns and migration rates are compared for two meander bends, one forested and one non-forested, on the Wabash River, near Grayville, Illinois. Flow data were obtained using acoustic Doppler current profilers (ADCP) for two large flow events in May and June 2011. LWD was mapped using a terrestrial LiDAR survey, and residence times for the LWD were estimated by comparing the survey data to time-series aerial photography. Rates of migration and planform evolution were determined through time-series analysis of aerial photography from 1938-2011. Results from this study show that near-bank LWD can have a significant influence on flow patterns through a meander bend and can disrupt helical flow near the outer bank, thereby reducing the effect of the high velocity core on the toe of the bank. Additionally, these effects influence migration rates and the planform evolution of meandering rivers.

  16. Mechanical and Hydrologic Effects of Riparian Vegetation on Critical Conditions for Streambank Stability: Upper Truckee River, California (United States)

    Simon, A.; Pollen, N. L.; Langendoen, E. J.


    The Upper Truckee River is the single largest contributor of sediment to Lake Tahoe with a large proportion of the suspended-sediment load coming from eroding streambanks. Recent advances in quantifying streambank processes highlight the combined effects of hydraulic erosion at the bank toe with geotechnical stability of the upper part of the bank and resulted in the development of a deterministic model of bank-toe erosion and streambank stability (Simon et al., 1999). The use of riparian vegetation in schemes of bank stabilization and stream restoration have become popular but are often implemented on a trial and error basis because of a lack of quantifiable information on the mechanical and hydrologic effects of vegetation on bank stability. This study, conducted along an unstable reach of the Upper Truckee River, combines field data with numerical modeling to quantify (1) hydraulic and geotechnical driving and resisting forces that control bank failures, (2) the mechanical and hydrologic effects of vegetation on shear strength, and (3) the critical conditions for bank stability with and without indigenous riparian species. Tests were conducted using three top-bank treatments: bare (control), Lemmon's willow, and young Lodgepole pine. The susceptibility of the bank toe to erosion by hydraulic forces was quantified by conducting submerged jet tests of in situ material to determine the erodibility coefficient (k) and the critical shear stress of the material. Drained, shear-strength parameters (cohesion and friction angle) of the banks were determined from borehole shear tests at various depths. Pore-water pressure and matric suction were monitored at three depths (30, 100, and 150 cm) with digital tensiometers to calculate changes in apparent cohesion for the period (September 2003 - May 2004) and to differentiate between the hydrologic effects of the two species. Root reinforcement of the two species was quantified by determining the relation between root

  17. Impacts of mute swans (Cygnus olor) on submerged aquatic vegetation in Illinois River Valley backwaters (United States)

    Stafford, Joshua D.; Michael W. Eichholz,; Adam C. Phillips,


    Wetland loss in North America has been considerable and well documented, and the establishment of exotic species in remaining wetlands can further reduce their ability to support native flora and fauna. In the Chesapeake Bay and Great Lakes ecosystems, exotic mute swans (Cygnus olor) have been found to negatively impact wetlands through degradation of submerged aquatic vegetation (SAV) communities. Mute swan populations have expanded into many areas of mid-continental North America outside the Great Lakes ecosystem, but the environmental impact of these populations is not well known. Mid-continental wetlands in North America differ in physical characteristics (e.g., size, depth, and permanency) and aquatic vegetation species composition compared to wetlands in other areas where mute swans have been studied and, thus, may be more or less susceptible to degradation from swan herbivory. To investigate the impact of mute swan herbivory on SAV communities in mid-continent wetlands, we used exclosures to prevent swans from foraging in 2 wetland complexes in central Illinois. Above-ground biomass of vegetation did not differ between exclosures and controls; however, mean below-ground biomass was greater in exclosures (52.0 g/m2, SE = 6.0) than in controls (34.4 g/m2 SE = 4.0). Thus, although swan densities were lower in our study region compared to that of previous studies, we observed potentially detrimental impacts of swan herbivory on below-ground biomass of SAV. Our results indicate that both above-ground and below-ground impacts of herbivory should be monitored, and below-ground biomass may be most sensitive to swan foraging.

  18. Survival of Saplings in Recovery of Riparian Vegetation of Pandeiros River (MG)


    Nathalle Cristine Alencar Fagundes; Lílian de Lima Braga; Wesley Alves Silva; Chirley Alves Coutinho; Walter Viana Neves; Ricardo Almeida de Souza; Maria das Dores Magalhães Veloso; Yule Roberta Ferreira Nunes


    ABSTRACT This study monitored the survival of saplings planted according to different recovery models in a riparian forest of the Pandeiros river (Januária, MG). The models consisted of planting the saplings in lines of 2 or 4 m with presence (T2S and T4S, respectively) or absence of direct seeding (T2 and T4, respectively). We planted 16,259 saplings of 17 botanical families, 32 genera and 33 species. The saplings, in general, presented a survival rate after one year of 34.4% (±1.8). The spe...

  19. Mineral weathering experiments to explore the effects of vegetation shifts in high mountain region (Wind River Range, Wyoming, USA) (United States)

    Mavris, Christian; Furrer, Gerhard; Dahms, Dennis; Anderson, Suzanne P.; Blum, Alex; Goetze, Jens; Wells, Aaron; Egli, Markus


    Climate change influences the evolution of soil and landscape. With changing climate, both flora and fauna must adapt to new conditions. It is unknown in many respects to what extent soils will react to warming and vegetation change. The aim of this study was to identify possible consequences for soils in a dry-alpine region with respect to weathering of primary minerals and leaching of elements under expected warming climate conditions due to shifts in vegetation. To achieve this, a field empirical approach was used in combination with laboratory weathering experiments simulating several scenarios. Study sites located in Sinks Canyon and in Stough Basin of the Wind River Range, Wyoming, USA, encompass ecotones that consist of tundra, forest, or sagebrush (from moist to dry, with increasing temperature, respectively). All soils are developed on granitoid moraines. The mineralogy of the soils along the altitudinal sequence was analysed using cathodoluminescence and X-ray diffraction, and revealed clear mineral transformations: biotite and plagioclase were both weathered to smectite while plagioclase also weathered to kaolinite. Cooler, wetter, altitude-dependent conditions seemed to promote weathering of these primary minerals. To test the impact of soil solutions from different ecotones on mineral weathering, aqueous extracts from topsoils (A horizons) were reacted with subsoils (B horizons) in batch experiments. Aqueous extracts of topsoil samples were generated for all three ecotones, and these solutions were characterized. For the batch experiments, the topsoil extracts were reacted for 1800 hours with the subsoil samples of the same ecotone, or with the subsoil samples from higher altitude ecotones. Solutions collected periodically during the experiments were measured using ICP-OES and ion chromatography. Dissolved Ca, Mg and K were mainly controlled by the chemical weathering of oligoclase, K-feldspar and biotite. With increasing altitude (and consequently

  20. Metals and arsenic in soils and corresponding vegetation at Central Elbe river floodplains (Germany)

    Energy Technology Data Exchange (ETDEWEB)

    Overesch, M. [Department for Geo- and Agroecology, Institute of Spatial Analysis and Planning in Areas of Intensive Agriculture, University of Vechta, P.O. Box 1553, D-49364 Vechta (Germany)]. E-mail:; Rinklebe, J. [Department of Soil Science, UFZ Center for Environmental Research Leipzig-Halle, Theodor-Lieser-Strasse 4, D-06120 Halle (Germany)]. E-mail:; Broll, G. [Department for Geo- and Agroecology, Institute of Spatial Analysis and Planning in Areas of Intensive Agriculture, University of Vechta, P.O. Box 1553, D-49364 Vechta (Germany)]. E-mail:; Neue, H.-U. [Department of Soil Science, UFZ Center for Environmental Research Leipzig-Halle, Theodor-Lieser-Strasse 4, D-06120 Halle (Germany)]. E-mail:


    Floodplain soils at the Elbe river are frequently polluted with metals and arsenic. High contents of these pollutants were detected down to subsoil layers. NH{sub 4}NO{sub 3}-extractable (phytoavailable) Cd, Ni, and Zn were elevated in horizons with high acidity. Among five common floodplain plant species, Artemisia vulgaris showed highest concentrations of Cd, Cu, and Hg, Alopecurus pratensis of As and Phalaris arundinacea of Ni, Pb, and Zn. Relationships were weak between metal concentrations in plants and phytoavailable stocks in soil. As and Hg uptake seems to be enhanced on long submerged soils. Enrichments of Cd and Hg are linked to a special plant community composition. Grassland herbage sampled in July/August revealed higher concentrations of As (+122%), Hg (+124%), and Pb (+3723%) than in May. To limit harmful transfers into the food chain, low-lying terraces and flood channels revealing highest contaminations or phytoavailabilities should be excluded from mowing and grazing. - Soils in the Elbe river floodplains are highly polluted with metals and arsenic and a critical enrichment in the grassland herbage seems to be most likely in flood channels or within special plant species.

  1. Temporal changes of meadow and peatbog vegetation in the landscape of a small-scale river valley in Central Roztocze

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    Bożenna Czarnecka


    Full Text Available The Szum is a right-side tributary of the Tanew River crossing the southern escarpment zone of the Central Roztocze region (SE Poland. Downstream of the strict river break in a section between the 10th and 12th km of the river course in the Szum valley, meadow and peatbog complexes have developed, associated with semi-hydrogenic and marshy soils. In an area of approx. 13 ha of the most valuable non-forest habitats, a variety of plant communities have been identified, including habitats of the Natura 2000 network and habitats that are protected under the Regulation of the Minister of the Environment (2001. These are, for instance, meadow associations Lysimachio vulgaris-Filipenduletum, Lythro-Filipenduletum, Filipendulo ulmariae-Menthetum longifoliae, Angelico-Cirsietum oleracei, and Cirsietum rivularis. The moss–sedge and sphagnum bog communities comprise noteworthy associations Caricetum limosae, Rhynchosporetum albae, Caricetum lasiocarpae, Caricetum paniceo-lepidocarpae, Caricetum davallianae, and Sphagnetum magellanici. These communities are composed of ca. 160 vascular plant species and 40 moss and liverwort species. In 1999–2014, the greatest changes occurred within macroforb meadows, i.e. small Angelico-Cirsietum oleracei and Cirsietum rivularis patches have been transformed into Lysimachio vulgaris-Filipenduletum, while some patches of the latter association have been transformed into a Caricetum acutiformis rush. Several patches of bog-spring associations Caricetum paniceo-lepidocarpae and Carici canescentis-Agrostietum caninae have been irretrievably destroyed. Sphagnetum magellanici appears to be the least stable community among the preserved peatbogs. The changes of meadow and peatbog vegetation observed for the last 15 years are a consequence of natural processes that take place in the river valley and to a large extent human activity connected with the so-called small-scale water retention as well as the presence of a beaver

  2. A Subpixel Classification of Multispectral Satellite Imagery for Interpetation of Tundra-Taiga Ecotone Vegetation (Case Study on Tuliok River Valley, Khibiny, Russia) (United States)

    Mikheeva, A. I.; Tutubalina, O. V.; Zimin, M. V.; Golubeva, E. I.


    The tundra-taiga ecotone plays significant role in northern ecosystems. Due to global climatic changes, the vegetation of the ecotone is the key object of many remote-sensing studies. The interpretation of vegetation and nonvegetation objects of the tundra-taiga ecotone on satellite imageries of a moderate resolution is complicated by the difficulty of extracting these objects from the spectral and spatial mixtures within a pixel. This article describes a method for the subpixel classification of Terra ASTER satellite image for vegetation mapping of the tundra-taiga ecotone in the Tuliok River, Khibiny Mountains, Russia. It was demonstrated that this method allows to determine the position of the boundaries of ecotone objects and their abundance on the basis of quantitative criteria, which provides a more accurate characteristic of ecotone vegetation when compared to the per-pixel approach of automatic imagery interpretation.

  3. Survival of Saplings in Recovery of Riparian Vegetation of Pandeiros River (MG

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    Nathalle Cristine Alencar Fagundes


    Full Text Available ABSTRACT This study monitored the survival of saplings planted according to different recovery models in a riparian forest of the Pandeiros river (Januária, MG. The models consisted of planting the saplings in lines of 2 or 4 m with presence (T2S and T4S, respectively or absence of direct seeding (T2 and T4, respectively. We planted 16,259 saplings of 17 botanical families, 32 genera and 33 species. The saplings, in general, presented a survival rate after one year of 34.4% (±1.8. The species with highest survival rates were Jacaranda brasiliana, with 85.0% (±13.5 of survival, Anadenanthera colubrina, with 70.1% (±7.0, and Triplaris gardneriana, with 69.3% (±9.1. Survival did not vary between the models tested, probably due to the short evaluation period (12 months.

  4. Vegetation development following stream/river restoration: more natural fluvial dynamics and morphology, return of aquatic and riparian plant species? (United States)

    Soons, M. B.


    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

  5. Benthic metabolism and denitrification in a river reach: a comparison between vegetated and bare sediments

    Directory of Open Access Journals (Sweden)

    Pierluigi VIAROLI


    Full Text Available This study aims at comparing biogeochemical processes in a Vallisneria spiralis meadow and in unvegetated sediments in the upper reach of the Mincio River (Northern Italy. The main hypothesis of this work is that meadows of rooted macrophytes affect benthic metabolism, enhancing capacity to retain nutrients (assimilation and dissipate (denitrification nitrogen loadings. In order to highlight how plants affect benthic processes in the riverbed, oxygen, dissolved inorganic carbon (DIC, soluble reactive phosphorus (SRP and inorganic nitrogen fluxes, together with denitrification rates, were measured from February to November 2007 in intact cores collected from stands of V. spiralis and bare sediments. V. spiralis biomass, elemental composition and growth rates were concurrently measured. Macrophyte biomass ranged from 60 to 120 g m-2 (as dry matter; growth rates followed a seasonal pattern from 0.001 in winter up to 0.080 d-1 in summer. On an annual basis, the macrophyte meadow was autotrophic with net O2 production and dissolved inorganic carbon uptake, while the bare sediment was net heterotrophic. The concurrent N assimilation by macrophytes and losses through denitrification led to similar N uptake/dissipation rates, up to 2500 mmol m-2 y-1. Under the very high NO3 - concentrations of the Mincio River, the competition between primary production and denitrification processes was also avoided. A significant ammonium regeneration from sediments to the water column occurred in the V. spiralis meadow, where plant debris and particulate matter accumulated. Here, SRP was also released into the water column, whilst in the bare sediment SRP fluxes were close to zero. Overall, V. spiralis affected the benthic metabolism enhancing the ecosystem capacity to control nitrogen contamination. However, the actual N removal rates were not sufficient to mitigate the pollution discharge.

  6. Riparian vegetation interacting with river morphology : modelling long-term ecosystem responses to invasive species, climate change, dams and river restoration

    NARCIS (Netherlands)

    van Oorschot, M.


    River systems are amongst the most dynamic and productive ecosystems in the world and provide habitats for numerous fluvial species. River flow and river shape determine the conditions that affect plant growth and survival. In turn, riparian plants can actively influence river flow and sedimentation

  7. Linking Vegetation Structure and Spider Diversity in Riparian and Adjacent Habitats in Two Rivers of Central Argentina: An Analysis at Two Conceptual Levels. (United States)

    Griotti, Mariana; Muñoz-Escobar, Christian; Ferretti, Nelson E


    The link between vegetation structure and spider diversity has been well explored in the literature. However, few studies have compared spider diversity and its response to vegetation at two conceptual levels: assemblage (species diversity) and ensemble (guild diversity). Because of this, we studied spider diversity in riparian and adjacent habitats of a river system from the Chacoan subregion in central Argentina and evaluated their linkage with vegetation structure at these two levels. To assess vegetation structure, we measured plant species richness and vegetation cover in the herb and shrub - tree layers. We collected spiders for over 6 months by using vacuum netting, sweep netting and pitfall traps. We collected 3,808 spiders belonging to 119 morphospecies, 24 families and 9 guilds. At spider assemblage level, SIMPROF analysis showed significant differences among studied habitats. At spider ensemble level, nevertheless, we found no significant differences among habitats. Concerning the linkage with vegetation structure, BIOENV test showed that spider diversity at either assemblage or ensemble level was not significantly correlated with the vegetation variables assessed. Our results indicated that spider diversity was not affected by vegetation structure. Hence, even though we found a pattern in spider assemblages among habitats, this could not be attributed to vegetation structure. In this study, we show that analyzing a community at two conceptual levels will be useful for recognizing different responses of spider communities to vegetation structure in diverse habitat types. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email:

  8. The role of vegetated areas on fish assemblage of the Paraná River floodplain: effects of different hydrological conditions

    Directory of Open Access Journals (Sweden)

    Juan José Neiff

    hydrological conditions. Disturbances in the hydrological pulses could reduce the biodiversity by modifying the connectivity of the floodplain with the river channel. Conservation of these vegetated wetlands requires maintenance of actual width range of connectivity that provide diverse habitat along the time.

  9. Anthropogenic Disturbances Create a New Vegetation Toposequence in the Gatineau River Valley, Quebec

    Directory of Open Access Journals (Sweden)

    Jason Laflamme


    Full Text Available This study measured changes in forest composition that have occurred since the preindustrial era along the toposequence of the Gatineau River Valley, Quebec, Canada (5650 km2, based on survey records prior to colonization (1804–1864 and recent forest inventories (1982–2006. Changes in forest cover composition over time were found to be specific to toposequence position. Maple and red oak are now more frequent on upper toposequence positions (+26%, +21%, respectively, whereas yellow birch, eastern hemlock, and American beech declined markedly (−34% to −17%. Poplar is more frequent throughout the landscape, but particularly on mid-toposequence positions (+40%. In contrast, white pine, frequent on all toposequence positions in the preindustrial forest, is now confined to shallow and coarse-textured soils (−20%. The preindustrial forest types of the study area were mostly dominated by maple, yellow birch, and beech, with strong components of white pine, hemlock, and eastern white cedar, either as dominant or codominant species. In a context of ongoing anthropogenic disturbances and environmental changes, it is probably not possible to restore many of these types, except where targeted silvicultural interventions could increase the presence of certain species. The new forest types observed should be managed to ensure continuity of vital ecosystem services and functions as disturbance regimes evolve.

  10. Comparison of water consumption in two riparian vegetation communities along the central Platte River, Nebraska, 2008–09 and 2011 (United States)

    Hall, Brent M.; Rus, David L.


    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

  11. The effect of submerged aquatic vegetation expansion on a declining turbidity trend in the Sacramento-San Joaquin River Delta (United States)

    Hestir, E.L.; Schoellhamer, David H.; Jonathan Greenberg,; Morgan-King, Tara L.; Ustin, S.L.


    Submerged aquatic vegetation (SAV) has well-documented effects on water clarity. SAV beds can slow water movement and reduce bed shear stress, promoting sedimentation and reducing suspension. However, estuaries have multiple controls on turbidity that make it difficult to determine the effect of SAV on water clarity. In this study, we investigated the effect of primarily invasive SAV expansion on a concomitant decline in turbidity in the Sacramento-San Joaquin River Delta. The objective of this study was to separate the effects of decreasing sediment supply from the watershed from increasing SAV cover to determine the effect of SAV on the declining turbidity trend. SAV cover was determined by airborne hyperspectral remote sensing and turbidity data from long-term monitoring records. The turbidity trends were corrected for the declining sediment supply using suspended-sediment concentration data from a station immediately upstream of the Delta. We found a significant negative trend in turbidity from 1975 to 2008, and when we removed the sediment supply signal from the trend it was still significant and negative, indicating that a factor other than sediment supply was responsible for part of the turbidity decline. Turbidity monitoring stations with high rates of SAV expansion had steeper and more significant turbidity trends than those with low SAV cover. Our findings suggest that SAV is an important (but not sole) factor in the turbidity decline, and we estimate that 21–70 % of the total declining turbidity trend is due to SAV expansion.

  12. Regional vegetation dynamics and its response to climate change—a case study in the Tao River Basin in Northwestern China

    International Nuclear Information System (INIS)

    Li, Changbin; Yang, Linshan; Wang, Shuaibing; Yang, Wenjin; Zhu, Gaofeng; Qi, Jiaguo; Zou, Songbing; Zhang, Feng


    The 30-year normalized-difference vegetation index (NDVI) time series from AVHRR/MODIS satellite sensors was used in this study to assess the regional vegetation dynamic changes in the Tao River Basin, which cuts across the Eastern Tibetan Plateau (ETP) and the Southwestern Loess Plateau (SLP). First, principal component and correlation analyses were carried out to determine the key climatic variables driving ecological change in the region. Then, regression models were tested to correlate NDVI with the selected climatic variables to determine their predictive power. Finally, Sen’s slope method was used to determine how terrestrial vegetation has responded to regional climate change in the region. The results indicated an average winter season NDVI value of 0.14 in the ETP but only 0.04 in the SLP. Primarily driven by increasing temperature, vegetation growth has generally been enhanced since 1981; spring NDVI increased by 0.03 every 10 years in the ETP and 0.02 in the SLP. Further, results from trend analyses suggest vegetation growth in the ETP shifted to earlier-start and earlier-end dates, however in the SLP, the growing season has been extended with an earlier-start and later-end date. The precipitation threshold for vegetation germination, measured by the cumulative spring rainfall, was found to be 44 mm for both the ETP and SLP. (paper)

  13. Vegetation greenness modelling in response to interannual precipitation and temperature changes between 2001 and 2012 in Liao River Basin in Jilin Province, China. (United States)

    Lin, Xiao-Sheng; Tang, Jie; Li, Zhao-Yang; Li, Hai-Yi


    Liao River basin in Jilin Province is the place of origin of the Dongliao River. This study gives a comprehensive analysis of the vegetation coverage in the region and provides a potential theoretical basis for ecological restoration. The seasonal variation of vegetation greenness and dynamics based on the Normalized Difference Vegetation Index (NDVI) in major land cover types in the region was studied. Analyzing the relationship NDVI, temperature and rainfall, we derived a set of predictor variables from 2001 to 2012 using the MODIS Terra level 1 Product (MOD02QKM). The results showed a general increasing trend in NDVI value in the region, while 34.63 % of the region showed degradation. NDVI values begin to rise from April when plants are regreening and they drop in September when temperature are decreasing and the leaves are falling in the study area and temperature was found decreasing during the period of 2001-2012 while rainfall showed an increasing trend. This model could be used to observe the change in vegetation greenness and the dynamic effects of temperature and rainfall. This study provided important data for the environmental protection of the basin area. And we hope to provide scientific analysis for controlling water and soil erosion, maintaining the sustainable productivity of land resources, enhancing the treatment of water pollution and stimulating the virtuous cycle of the ecological system.


    Directory of Open Access Journals (Sweden)



    Full Text Available A GIS tool to evaluate the spatial evolution of hydro-thermic features during growing season of vegetable crops in Elbe River lowland (Polabi. This article presents the results of the first study on combined mezoclimatological, microclimatological and topographical tools for evaluating precision farming in the growth of vegetable crops in the Elbe River lowland (Polabi region from the Czech Republic. We assess the variability of basically climatological characteristics in relation to topographic characteristics at the regional (Polabi and local (agricultural farm scales. At regional scale, interpolation approach is based on local linear regression and universal kriging interpolation. At local scale, two conventional interpolation methods, spline and local ordinary kriging with a Gaussian model variance across the fields, were applied. The local spline interpolators have been used in developing digital elevation models (DEMs and to determine the slope angle inclination of vegetable fields. The DEMs of the vegetable crops fields was developed at a 10 m x 10 m resolution based on elevation data collected in the field by a hand-held RTK- Global Positioning System receiver. This tool allowed the distinction of microclimatic conditions that produce altitude-slope-related patterns of the spatial-temporal distribution of the basic meteorological elements during growing season of vegetable crops. The effect of slope on diurnal extreme temperatures in the vegetable cropped field conditions was more pronounced than that of elevation. Accordingly to developed maps, the warmest and longest duration of sunshine, and the least precipitation totals during growing season occurred in the middle part of Polabi.

  15. Estimating Vegetation Primary Production in the Heihe River Basin of China with Multi-Source and Multi-Scale Data.

    Directory of Open Access Journals (Sweden)

    Tianxiang Cui

    Full Text Available Estimating gross primary production (GPP and net primary production (NPP are significant important in studying carbon cycles. Using models driven by multi-source and multi-scale data is a promising approach to estimate GPP and NPP at regional and global scales. With a focus on data that are openly accessible, this paper presents a GPP and NPP model driven by remotely sensed data and meteorological data with spatial resolutions varying from 30 m to 0.25 degree and temporal resolutions ranging from 3 hours to 1 month, by integrating remote sensing techniques and eco-physiological process theories. Our model is also designed as part of the Multi-source data Synergized Quantitative (MuSyQ Remote Sensing Production System. In the presented MuSyQ-NPP algorithm, daily GPP for a 10-day period was calculated as a product of incident photosynthetically active radiation (PAR and its fraction absorbed by vegetation (FPAR using a light use efficiency (LUE model. The autotrophic respiration (Ra was determined using eco-physiological process theories and the daily NPP was obtained as the balance between GPP and Ra. To test its feasibility at regional scales, our model was performed in an arid and semi-arid region of Heihe River Basin, China to generate daily GPP and NPP during the growing season of 2012. The results indicated that both GPP and NPP exhibit clear spatial and temporal patterns in their distribution over Heihe River Basin during the growing season due to the temperature, water and solar influx conditions. After validated against ground-based measurements, MODIS GPP product (MOD17A2H and results reported in recent literature, we found the MuSyQ-NPP algorithm could yield an RMSE of 2.973 gC m(-2 d(-1 and an R of 0.842 when compared with ground-based GPP while an RMSE of 8.010 gC m(-2 d(-1 and an R of 0.682 can be achieved for MODIS GPP, the estimated NPP values were also well within the range of previous literature, which proved the reliability of

  16. Variations in annual water-energy balance and their correlations with vegetation and soil moisture dynamics: A case study in the Wei River Basin, China

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Shengzhi; Huang, Qiang; Leng, Guoyong; Zhao, Menglong; Meng, Erhao


    It is of importance to investigate watershed water-energy balance variations and to explore their correlations with vegetation and soil moisture dynamics, which helps better understand the interplays between underlying surface dynamics and the terrestrial water cycle. The heuristic segmentation method was adopted to identify change points in the parameter to series in Fu's equation belonging to the Budyko framework in the Wei River Basin (WRB) and its sub-basins aiming to examine the validity of stationary assumptions. Additionally, the cross wavelet analysis was applied to explore the correlations between vegetation and soil moisture dynamics and to variations. Results indicated that (1) the omega variations in the WRB are significant, with some change points identified except for the sub-basin above Zhangjiashan, implying that the stationarity of omega series in the WRB is invalid except for the sub-basin above Zhangjiashan; (2) the correlations between soil moisture series and to series are weaker than those between Normalized Difference Vegetation Index (NDVI) series and omega series; (3) vegetation dynamics show significantly negative correlations with omega variations in 1983-2003 with a 4-8 year signal in the whole WRB, and both vegetation and soil moisture dynamics exert strong impacts on the parameter omega changes. This study helps understanding the interactions between underlying land surface dynamics and watershed water-energy balance. (C) 2017 Elsevier B.V. All rights reserved.

  17. Oldman river dam mitigation program downstream vegetation project report, Volume II: The potential effects of an operating plan for the Oldman River dam on Riparian cottonwood forests

    Energy Technology Data Exchange (ETDEWEB)

    Mahoney, J.M.


    Extensive cottonwood (poplar) forests exist in the Oldman River valley downstream of the Oldman River dam. Studies of similar forests in nearby river valleys and elsewhere on the western prairies have found significant declines of some riparian forests following river damming. This investigation was initiated to determine the causes of cottonwood forest decline downstream from existing dams in southern Alberta; inventory the existing river valley forests in the Oldman Basin; establish study sites in the Oldman River forests to monitor changes in forest status following commissioning of the Oldman River dam, and evaluate the probable impact of proposed operating plans for the Oldman River dam and associated water control structures on downstream forests. This report summarizes the progress made in the analyses of the probable effects on the survival of the forests, including a discussion of the hydrological conditions essential for cottonwood forest regeneration and an explanation of the effects of altering these characteristics on riparian forests; the hydrological alterations expected along various river reaches in the Oldman Basin with the implementation of the proposed OD05 Oldman Dam operating plan; and preliminary analyses of the problem impacts of the OD05 operating plan on the cottonwood forests along these reaches.

  18. Groundwater–surface water interactions, vegetation dependencies and implications for water resources management in the semi-arid Hailiutu River catchment, China – a synthesis

    Directory of Open Access Journals (Sweden)

    Y. Zhou


    Full Text Available During the last decades, large-scale land use changes took place in the Hailiutu River catchment, a semi-arid area in northwest China. These changes had significant impacts on the water resources in the area. Insights into groundwater and surface water interactions and vegetation-water dependencies help to understand these impacts and formulate sustainable water resources management policies. In this study, groundwater and surface water interactions were identified using the baseflow index at the catchment scale, and hydraulic and water temperature methods as well as event hydrograph separation techniques at the sub-catchment scale. The results show that almost 90% of the river discharge consists of groundwater. Vegetation dependencies on groundwater were analysed from the relationship between the Normalized Difference Vegetation Index (NDVI and groundwater depth at the catchment scale and along an ecohydrogeological cross-section, and by measuring the sap flow of different plants, soil water contents and groundwater levels at different research sites. The results show that all vegetation types, i.e. trees (willow (Salix matsudana and poplar (Populus simonii, bushes (salix – Salix psammophila, and agricultural crops (maize – Zea mays, depend largely on groundwater as the source for transpiration. The comparative analysis indicates that maize crops use the largest amount of water, followed by poplar trees, salix bushes, and willow trees. For sustainable water use with the objective of satisfying the water demand for socio-economical development and to prevent desertification and ecological impacts on streams, more water-use-efficient crops such as sorghum, barley or millet should be promoted to reduce the consumptive water use. Willow trees should be used as wind-breaks in croplands and along roads, and drought-resistant and less water-use intensive plants (for instance native bushes should be used to vegetate sand dunes.

  19. Feedbacks among Floods, Pioneer Woody Vegetation, and Channel Change in Sand-Bed Rivers: Insights from Field Studies of Controlled Flood Releases and Models (United States)

    Wilcox, A. C.; Shafroth, P. B.; Lightbody, A.; Stella, J. C.; Bywater-Reyes, S.; Kiu, L.; Skorko, K.


    To investigate feedbacks between flow, geomorphic processes, and pioneer riparian vegetation in sand-bed rivers, we are combining field, hydraulic modeling, and laboratory simulations. Field studies have examined the response of woody riparian seedlings and channel morphology to prescribed dam-released floods that have been designed in part to maintain a native riparian woodland system on the Bill Williams River, Arizona, USA. Through monitoring of floods over a 7-year period, we have observed temporal and spatial variations in channel response. Floods have produced geomorphic and vegetation responses that varied with distance downstream of a dam, with scour and associated seedling mortality closer to the dam and aggradation and burial-induced mortality in a downstream reach with greater sediment supply. We also have observed that as vegetation grows beyond the seedling stage, its stabilizing effect on bars and its drag effect on flow progressively increases, such that floods of similar sizes but at different times may produce markedly different downstream responses as a function of vegetation characteristics. We also observed greater mortality among nonnative Tamarix spp. (tamarisk) seedlings than among native Salix gooddingii (Goodding's willow) seedlings, likely as a result of the greater first-year growth of willow relative to tamarisk. Combining field observations with modeling predictions of local hydraulics for the flood events we have studied is being used to draw linkages between hydraulics, channel change, and plant response at the patch and bar scale. In addition, mechanistic linkages are being examined using a field-scale laboratory stream channel, where seedlings of Tamarix spp. (tamarisk) and Populus fremontii (cottonwood) were planted and subjected to floods with varying sediment feed rate and plant configurations. The floods conveyed by our model channel were generally insufficient to scour the woody seedlings we planted, but changes in bar size and


    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.; Jannik, T.; Fledderman, P.


    {sup 137}Cs released during 1954-1974 from nuclear production reactors on the Savannah River Site, a US Department of Energy nuclear materials production site in South Carolina, contaminated a portion of the Savannah River floodplain known as Creek Plantation. {sup 137}Cs activity concentrations have been measured in Creek Plantation since 1974 making it possible to calculate effective half-lives for {sup 137}Cs in soil and vegetation and assess the spatial distribution of contaminants on the floodplain. Activity concentrations in soil and vegetation were higher near the center of the floodplain than near the edges as a result of frequent inundation coupled with the presence of low areas that trapped contaminated sediments. {sup 137}Cs activity was highest near the soil surface, but depth related differences diminished with time as a likely result of downward diffusion or leaching. Activity concentrations in vegetation were significantly related to concentrations in soil. The plant to soil concentration ratio (dry weight) averaged 0.49 and exhibited a slight but significant tendency to decrease with time. The effective half-lives for {sup 137}Cs in shallow (0-7.6 cm) soil and in vegetation were 14.9 (95% CI = 12.5-17.3) years and 11.6 (95% CI = 9.1-14.1) years, respectively, and rates of {sup 137}Cs removal from shallow soil and vegetation did not differ significantly among sampling locations. Potential health risks on the Creek Plantation floodplain have declined more rapidly than expected on the basis of radioactive decay alone because of the relatively short effective half-life of {sup 137}Cs.

  1. Wide-area estimates of evapotranspiration by red gum (Eucalyptus camaldulensis) and associated vegetation in the Murray-Darling River Basin, Australia (United States)

    Nagler, Pamela L.; Doody, Tanya M.; Glenn, Edward P.; Jarchow, Christopher J.; Barreto-Munoz, Armando; Didan, Kamel


    Floodplain red gum forests (Eucalyptus camaldulensis plus associated grasses, reeds and sedges) are sites of high biodiversity in otherwise arid regions of southeastern Australia. They depend on periodic floods from rivers, but dams and diversions have reduced flood frequencies and volumes, leading to deterioration of trees and associated biota. There is a need to determine their water requirements so environmental flows can be administered to maintain or restore the forests. Their water requirements include the frequency and extent of overbank flooding, which recharges the floodplain soils with water, as well as the actual amount of water consumed in evapotranspiration (ET). We estimated the flooding requirements and ET for a 38 134 ha area of red gum forest fed by the Murrumbidgee River in Yanga National Park, New South Wales. ET was estimated by three methods: sap flux sensors placed in individual trees; a remote sensing method based on the Enhanced Vegetation Index from MODIS satellite imagery and a water balance method based on differences between river flows into and out of the forest. The methods gave comparable estimates yet covered different spatial and temporal scales. We estimated flood frequency and volume requirements by comparing Normalized Difference Vegetation Index values from Landsat images with flood history from 1995 to 2014, which included both wet periods and dry periods. ET during wet years is about 50% of potential ET but is much less in dry years because of the trees' ability to control stomatal conductance. Based on our analyses plus other studies, red gum trees at this location require environmental flows of 2000 GL yr−1 every other year, with peak flows of 20 000 ML d−1, to produce flooding sufficient to keep them in good condition. However, only about 120–200 GL yr−1 of river water is consumed in ET, with the remainder flowing out of the forest where it enters the Murray River system.

  2. Impact of urban contamination of the La Paz River basin on thermotolerant coliform density and occurrence of multiple antibiotic resistant enteric pathogens in river water, irrigated soil and fresh vegetables. (United States)

    Poma, Violeta; Mamani, Nataniel; Iñiguez, Volga


    La Paz River in Andean highlands is heavily polluted with urban run-off and further contaminates agricultural lowlands and downstream waters at the Amazon watershed. Agricultural produce at this region is the main source of vegetables for the major Andean cities of La Paz and El Alto. We conducted a 1 year study, to evaluate microbial quality parameters and occurrence of multiple enteropathogenic bacteria (Enterohemorrhagic E. coli-EHEC, Enteroinvasive E. coli or Shigella-EIEC/Shigella, Enteroaggregative E. coli-EAEC, Enteropathogenic E. coli-EPEC Enterotoxigenic E. coli-ETEC and Salmonella) and its resistance to 11 antibiotics. Four sampling locations were selected: a fresh mountain water reservoir (un-impacted, site 1) and downstream sites receiving wastewater discharges (impacted, sites 2-4). River water (sites 1-4, N = 48), and soil and vegetable samples (site 3, N = 24) were collected during dry (April-September) and rainy seasons (October-March). Throughout the study, thermotolerant coliform density values at impacted sites greatly exceeded the guidelines for recreational and agricultural water uses. Seasonal differences were found for thermotolerant coliform density during dry season in water samples nearby a populated and hospital compound area. In contrast to the un-impacted site, where none of the tested enteropathogens were found, 100 % of surface water, 83 % of soil and 67 % of vegetable samples at impacted sites, were contaminated with at least one enteropathogen, being ETEC and Salmonella the most frequently found. ETEC isolates displayed different patterns of toxin genes among sites. The occurrence of enteropathogens was associated with the thermotolerant coliform density. At impacted sites, multiple enteropathogens were frequently found during rainy season. Among isolated enteropathogens, 50 % were resistant to at least two antibiotics, with resistance to ampicillin, nalidixic acid, trimethoprim-sulfamethoxazole and tetracycline commonly

  3. Characterisation of the impacts of pre- and post- remedial contaminant loads from the Rum Jungle on riparian vegetation and fishes of the Finniss River system

    International Nuclear Information System (INIS)

    Jeffree, R.A.


    The status of the riparian vegetation and fish biodiversity in the Finniss River (FR) system is compared before and after remediation at the Rum Jungle (RJ) mine site. Whereas observations recorded during pre-remedial field studies in 1974 indicate no obvious effects of mine effluents on the riparian vegetation in the FR, the impacts in the Eeast Branch were severe. The tolerance to Cu that has been measured in one fish species (Gale et al., submitted) suggests the possibility that the exposure of the fish community to contaminant loadings over more than four decades may have led to the development of tolerance that may also contribute to the ecological recovery that has been observed

  4. Spatial and temporal relationships between the invasive snail Bithynia tentaculata and submersed aquatic vegetation in Pool 8 of the Upper Mississippi River (United States)

    Weeks, Alicia M.; DeJager, Nathan R.; Haro, Roger J.; Sandland, Greg J.


    Bithynia tentaculata is an invasive snail that was first reported in Lake Michigan in 1871 and has since spread throughout a number of freshwater systems of the USA. This invasion has been extremely problematic in the Upper Mississippi River as the snails serve as intermediate hosts for several trematode parasites that have been associated with waterfowl mortality in the region. This study was designed to assess the abundance and distribution of B. tentaculata relative to submersed aquatic vegetation as macrophytes provide important nesting and food resources for migrating waterfowl. Temporal changes in both vegetation and snail densities were compared between 2007 and 2015. Between these years, B. tentaculata densities have nearly quadrupled despite minor changes in vegetation abundance, distribution and composition. Understanding the spatial distribution of B. tentaculata in relation to other habitat features, including submersed vegetation, and quantifying any further changes in the abundance and distribution of B. tentaculata over time will be important for better identifying areas of risk for disease transmission to waterfowl.

  5. Comparison of vegetation roughness descriptions

    NARCIS (Netherlands)

    Augustijn, Dionysius C.M.; Huthoff, Freek; van Velzen, E.H.; Altinakar, M.S.; Kokpinar, M.A.; Aydin, I.; Cokgor, S.; Kirkgoz, S.


    Vegetation roughness is an important parameter in describing flow through river systems. Vegetation impedes the flow, which affects the stage-discharge curve and may increase flood risks. Roughness is often used as a calibration parameter in river models, however when vegetation is allowed to

  6. Spatial and temporal variation In streamside herbaceous vegetation of the Upper Verde River: 1996-2001 [Chapter 7 (United States)

    Alvin L. Medina; Jonathan W. Long


    Streamside environments are inherently dynamic, yet streamside vegetation plays a key stabilizing role on riparian and aquatic habitats (Van Devender and Spaulding 1979; Van Devender and others 1987). Because of its dynamism, streamside vegetation is rarely the subject of classification analyses, yet it is a focal point for land managers regulating land uses, such as...

  7. Summer bird/vegetation associations in Tamarisk and native habitat along the Pecos River, southeastern New Mexico (United States)

    M. F. Livingston; S. D. Schemnitz


    The middle Pecos River lies in the short-grass prairie ecotype and lacked a substantial woodland community prior to tamarisk (Tamarisk chinensis) invasion. Tamarisk control is a concern for land managers on the Pecos River and other Southwestern riparian systems. Our research is part of a long term study investigating hydrological and wildlife response to tamarisk...

  8. Development of a high-resolution binational vegetation map of the Santa Cruz River riparian corridor and surrounding watershed, southern Arizona and northern Sonora, Mexico (United States)

    Wallace, Cynthia S.A.; Villarreal, Miguel L.; Norman, Laura M.


    This report summarizes the development of a binational vegetation map developed for the Santa Cruz Watershed, which straddles the southern border of Arizona and the northern border of Sonora, Mexico. The map was created as an environmental input to the Santa Cruz Watershed Ecosystem Portfolio Model (SCWEPM) that is being created by the U.S. Geological Survey for the watershed. The SCWEPM is a map-based multicriteria evaluation tool that allows stakeholders to explore tradeoffs between valued ecosystem services at multiple scales within a participatory decision-making process. Maps related to vegetation type and are needed for use in modeling wildlife habitat and other ecosystem services. Although detailed vegetation maps existed for the U.S. side of the border, there was a lack of consistent data for the Santa Cruz Watershed in Mexico. We produced a binational vegetation classification of the Santa Cruz River riparian habitat and watershed vegetation based on NatureServe Terrestrial Ecological Systems (TES) units using Classification And Regression Tree (CART) modeling. Environmental layers used as predictor data were derived from a seasonal set of Landsat Thematic Mapper (TM) images (spring, summer, and fall) and from a 30-meter digital-elevation-model (DEM) grid. Because both sources of environmental data are seamless across the international border, they are particularly suited to this binational modeling effort. Training data were compiled from existing field data for the riparian corridor and data collected by the NM-GAP (New Mexico Gap Analysis Project) team for the original Southwest Regional Gap Analysis Project (SWReGAP) modeling effort. Additional training data were collected from core areas of the SWReGAP classification itself, allowing the extrapolation of the SWReGAP mapping into the Mexican portion of the watershed without collecting additional training data.

  9. Investigations of the vegetation along the river Laagen in connection with expansion of the Lower Vinstra Power Station; Vegetasjonsundersoekelser i Laagen i forbindelse med utvidelse av Nedre Vinstra kraftverk

    Energy Technology Data Exchange (ETDEWEB)

    Brandrud, T.E.; Mjelde, M [Norsk Inst. for Vannforskning, Oslo (Norway); Bendiksen, E. [Norsk Inst. for Naturforskning, Trondheim (Norway)


    To qualify for a licence to expand, the Norwegian hydroelectric power plant Lower Vinstra Power Station had to perform botanical investigations of the aquatic and riverside vegetation (riparian vegetation) along the affected part of the river Gudbrandsdalslaagen, between Harpefoss and Faavang. The investigations took place in 1990-1994 and is described in the present report. The riverside vegetation was stable throughout the entire period, overgrowing weakly. The aquatic vegetation exibited greater fluctuations, including episodic decline in unstable areas. Aquatic vegetation declined and vanished in areas with large as well as with little diurnal variation of the water level, which is primarily due to flooding episods. Erosion or essential changes in aquatic or riverside vegetation caused by increased diurnal regulation (HEP regulations) cannot be demonstrated with any great probability. 13 refs., 14 figs., 8 tabs.

  10. Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng [School of Life Science, Nanjing University, Xianlin Road 163, Qixia District, Nanjing, 210046 (China); An, Ru [School of Earth Science and Engineering, Hohai University, Xikang Road 129, Nanjing, 210098 (China); Li, Jianlong, E-mail: [School of Life Science, Nanjing University, Xianlin Road 163, Qixia District, Nanjing, 210046 (China)


    The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie–Ames–Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37 g cm{sup −2} yr{sup −1}. The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31 g cm{sup −2} yr{sup −2}. During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09 g cm{sup −2} yr{sup −2}, respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40 g cm{sup −2} yr{sup −2} and − 0.08 g cm{sup −2} yr{sup −2}, respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation

  11. Vegetation dynamics and its driving forces from climate change and human activities in the Three-River Source Region, China from 1982 to 2012

    International Nuclear Information System (INIS)

    Zhang, Ying; Zhang, Chaobin; Wang, Zhaoqi; Chen, Yizhao; Gang, Chengcheng; An, Ru; Li, Jianlong


    The Three-River Source Region (TRSR), a region with key importance to the ecological security of China, has undergone climate changes and a shift in human activities driven by a series of ecological restoration projects in recent decades. To reveal the spatiotemporal dynamics of vegetation dynamics and calculate the contributions of driving factors in the TRSR across different periods from 1982 to 2012, net primary productivity (NPP) estimated using the Carnegie–Ames–Stanford approach model was used to assess the status of vegetation. The actual effects of different climatic variation trends on interannual variation in NPP were analyzed. Furthermore, the relationships of NPP with different climate factors and human activities were analyzed quantitatively. Results showed the following: from 1982 to 2012, the average NPP in the study area was 187.37 g cm"−"2 yr"−"1. The average NPP exhibited a fluctuation but presented a generally increasing trend over the 31-year study period, with an increase rate of 1.31 g cm"−"2 yr"−"2. During the entire study period, the average contributions of temperature, precipitation, and solar radiation to NPP interannual variation over the entire region were 0.58, 0.73, and 0.09 g cm"−"2 yr"−"2, respectively. Radiation was the climate factor with the greatest influence on NPP interannual variation. The factor that restricted NPP increase changed from temperature and radiation to precipitation. The average contributions of climate change and human activities to NPP interannual variation were 1.40 g cm"−"2 yr"−"2 and − 0.08 g cm"−"2 yr"−"2, respectively. From 1982 to 2000, the general climate conditions were favorable to vegetation recovery, whereas human activities had a weaker negative impact on vegetation growth. From 2001 to 2012, climate conditions began to have a negative impact on vegetation growth, whereas human activities made a favorable impact on vegetation recovery. - Highlights: • Partitioned the

  12. [Variation characteristics and influencing factors of actual evapotranspiration under various vegetation types: A case study in the Huaihe River Basin, China. (United States)

    Wu, Rong Jun; Xing, Xiao Yong


    The actual evapotranspiration was modelled utilizing the boreal ecosystem productivity simulator (BEPS) in Huaihe River Basin from 2001 to 2012. In the meantime, the quantitative analyses of the spatial-temporal variations of actual evapotranspiration characteristics and its influencing factors under different vegetation types were conducted. The results showed that annual evapotranspiration gradually decreased from southeast to northwest, tended to increase annually, and the monthly change for the average annual evapotranspiration was double-peak curve. The differences of evapotranspiration among vegetation types showed that the farmland was the largest contributor for the evapotranspiration of Huaihe Basin. The annual actual evapotranspiration of the mixed forest per unit area was the largest, and that of the bare ground per unit area was the smallest. The changed average annual evapotranspiration per unit area for various vegetation types indicated an increased tendency other than the bare ground, with a most significant increase trend for the evergreen broadleaf forest. The thermodynamic factors (such as average temperature) were the dominant factors affecting the actual evapotranspiration in the Huaihe Basin, followed by radiation and moisture factors.

  13. Contributions of large wood to the initial establishment and diversity of riparian vegetation in a bar-braided temperate river


    Nakamura, Futoshi; Fuke, Nao; Kubo, Mayumi


    The purpose of this study was to examine the effects of large wood (LW) on the physical environment and the initial establishment of vascular plant species in the Rekifune River, a large bar-braided monsoonal river in Japan. The physical environment and the diversity and composition of plant species were compared in relation to the orientation of LW pieces. We found that shading effects were more prevalent in the immediate vicinity of LW pieces than in quadrats distant from LW. The effect was...

  14. Tanana River Monitoring and Research Program: Relationships Among Bank Recession, Vegetation, Soils, Sediments and Permafrost on the Tanana River Near Fairbanks, Alaska. (United States)


    influencing bank erosion along the Tanana River. Soils The regional soil association along both reaches is loamy, consisting of nearly level histic pergelic ...conspicuous. Most areas of this association are flooded occasionally. The histic pergelic cryaquepts occur in poorly drained, low areas such as meander...great depth; usually occupy natural levees. 6Histic pergelic cryaquepts: soils with texture ranging from gravelly sand to clay, color from gray to

  15. Vegetation and soil at the terraces of the Dřevnice and the Morava rivers after flood

    Czech Academy of Sciences Publication Activity Database

    Šerá, Božena; Cudlín, Pavel; Dušek, L.; Hofman, J.


    Roč. 27, č. 4 (2008), s. 430-445 ISSN 1335-342X R&D Projects: GA ČR(CZ) GA103/99/1470 Institutional research plan: CEZ:AV0Z60870520 Keywords : flood * vegetation change * invasive plant * life strategy * soil parameter * soil contamination Subject RIV: EH - Ecology, Behaviour

  16. Phenological response of vegetation to upstream river flow in the Heihe Rive basin by time series analysis of MODIS data

    NARCIS (Netherlands)

    Jia, L.; Shang, H.L.; Hu, G.; Menenti, M.


    Liquid and solid precipitation is abundant in the high elevation, upper reach of the Heihe River basin in northwestern China. The development of modern irrigation schemes in the middle reach of the basin is taking up an increasing share of fresh water resources, endangering the oasis and traditional

  17. Soil erosion and sediment yield and their relationships with vegetation cover in upper stream of the Yellow River

    NARCIS (Netherlands)

    Ouyang, W.; Hao, F.; Skidmore, A.K.; Toxopeus, A.G.


    Soil erosion is a significant concern when considering regional environmental protection, especially in the Yellow River Basin in China. This study evaluated the temporal-spatial interaction of land cover status with soil erosion characteristics in the Longliu Catchment of China, using the Soil and

  18. Holocene Vegetation Succession and Response to Climate Change on the South Bank of the Heilongjiang-Amur River, Mohe County, Northeast China

    Directory of Open Access Journals (Sweden)

    Chao Zhao


    Full Text Available Pollen samples from peat sediments on the south bank of the Heilongjiang River in northern Northeast China (NE China were analyzed to reconstruct the historical response of vegetation to climate change since 7800 cal yr BP. Vegetation was found to have experienced five successions from cold-temperate mixed coniferous and broadleaved forest to forest-steppe, steppe-woodland, steppe, and finally meadow-woodland. From 7800 to 7300 cal yr BP, the study area was warmer than present, and Betula, Larix, and Picea-dominated mixed coniferous and broadleaved forests thrived. Two cooling events at 7300 cal yr BP and 4500 cal yr BP led to a decrease in Betula and other broadleaved forests, whereas herbs of Poaceae expanded, leading to forest-steppe and then steppe-woodland environments. After 2500 cal yr BP, reduced temperatures and a decrease in evaporation rates are likely to have resulted in permafrost expansion and surface ponding, with meadow and isolated coniferous forests developing a resistance to the cold-wet environment. The Holocene warm period in NE China (7800–7300 cal yr BP could have resulted in a strengthening of precipitation in northernmost NE China and encouraged the development of broadleaved forests.

  19. General Classification Handbook for Floodplain Vegetation in Large River Systems. Chapter 1 of Book 2, Collection of Environmental Data (United States)


    tuberculatus WM Amorpha A. fruiticosa WMS Betula B. nigra FF, LF Bidens B. cernua, B. frondosa SMA Carex C. spp.1 SM Carya C. cordiformis, C. illinoensis LF...include pecan ( Carya ), hickory ( Carya ), river birch (Betula), sycamore (Platanus), and red/black oak (Quercus). This general class is most com- mon...near the edge of the floodplain, or out of the floodplain. This general class typi- cally consists of red or white oak (Quercus), hickory ( Carya

  20. Selection and cultivation of final vegetative cover for closed waste sites at the Savannah River Site, SC

    International Nuclear Information System (INIS)

    Cook, J.R.; Salvo, S.K.


    Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as a vegetative cover for most sites. Consequently, the sites require periodic mowing and other expensive annual maintenance practices. The purpose of this five year study was to evaluate alternative plant material for use on wastes sites that is quickly and easily established and economically maintained, retards water infiltration, provides maximum year-round evapotranspiration, is ecologically acceptable and does not harm the closure cap. The results of the study are described in this report and suggest that two species of bamboo (Phyllostachys bissetii and P. rubromarainata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites. These large species of bamboo will also reduce the probability of intrusion by humans, animals and deeply rooted plant species

  1. Primary successions of vegetation on technogenic sand patches in oil and gas producing districts of the middle Ob' river basin

    Energy Technology Data Exchange (ETDEWEB)

    Shilova, I I


    Intensive economic exploitation of the natural resources of the oil-and-gas producing districts of the central Ob' basin has led to increased exposure of sandy patches over the landscape. These sandy areas are becoming a common site. Technogenic factors involved include, for example, construction projects, oil-drilling and the like. Exposure is accelerated by wind and water erosion. Efforts are underway to reintroduce verdure in the region, and a study has been underway of the features of the ecotope and the stages of natural overgrowth of the area of reclamation. This overgrowth is proceeding well. Vegetation is of the syngenetic succession type, involving four successive stages and formation of associations of a zonal character. Seventy-four species of yeast, 2 species of fungi, 2 of lichens, 19 of Bryophyton and 106 of vascular spore- and covered-seed plants of the area have been recorded, and are tabulated. Recultivation will require due attention to existing conditions. 14 references.

  2. Spatiotemporal extremes of temperature and precipitation during 1960-2015 in the Yangtze River Basin (China) and impacts on vegetation dynamics (United States)

    Cui, Lifang; Wang, Lunche; Qu, Sai; Singh, Ramesh P.; Lai, Zhongping; Yao, Rui


    Recently, extreme climate variation has been studied in different parts of the world, and the present study aims to study the impacts of climate extremes on vegetation. In this study, we analyzed the spatiotemporal variations of temperature and precipitation extremes during 1960-2015 in the Yangtze River Basin (YRB) using the Mann-Kendall (MK) test with Sen's slope estimator and kriging interpolation method based on daily precipitation (P), maximum temperature (T max), and minimum temperature (T min). We also analyzed the vegetation dynamics in the YRB during 1982-2015 using Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index (NDVI) datasets and investigated the relationship between temperature and precipitation extremes and NDVI using Pearson correlation coefficients. The results showed a pronounced increase in the annual mean maximum temperature (T nav) and mean minimum temperature (T xav) at the rate of 0.23 °C/10 years and 0.15 °C/10 years, respectively, during 1960-2015. In addition, the occurrence of warm days and warm nights shows increasing trends at the rate of 1.36 days/10 years and 1.70 days/10 years, respectively, while cold days and cold nights decreased at the rate of 1.09 days/10 years and 2.69 days/10 years, respectively, during 1960-2015. The precipitation extremes, such as very wet days (R95, the 95th percentile of daily precipitation events), very wet day precipitation (R95p, the number of days with rainfall above R95), rainstorm (R50, the number of days with rainfall above 50 mm), and maximum 1-day precipitation (RX1day), all show pronounced increasing trends during 1960-2015. In general, annual mean NDVI over the whole YRB increased at the rate of 0.01/10 years during 1982-2015, with an increasing transition around 1994. Spatially, annual mean NDVI increased in the northern, eastern, and parts of southwestern YRB, while it decreased in the YRD and parts of southern YRB during 1982-2015. The correlation


    Directory of Open Access Journals (Sweden)

    Leszek Pływaczyk


    Full Text Available In soils, where the water table is deeply located and has a minor impact on the moisture content of the surface layer, we are dealing with the precipitation-and-water type of water management. If underground water level is close to the surface, the top stratum of the soil, apart from precipitation, is additionally fed by water absorption from underground waters. Then we are dealing with ground-and-water type of management. We consider such types of water management of soil in the area of the left-bank valley of the Odra river, above and below the dam in Brzeg Dolny. The dominant soil types here are middle fen soils, based on middle clay and heavy clay as well as loam, which, in conditions of either excess or deficiency of moisture, are difficult to cultivate. The work compares water management of two soil profiles in vegetation periods between 2004 and 2009. The formation of underground waters, meteorological conditions and the course of the water reserves in the strata 0–50 cm and 0–100 cm were estimated with various supplying conditions of the active stratum of the soil. The volume of the supply with percolated water from underground water of the layer 50–100 cm on approximately 75–90 mm was also estimated. This value was mainly dependent on the depth of the retention of the water table of the soil profile above the level in Brzeg Dolny.

  4. Understory plant diversity in mixed and pure plantations of jatropha curcas vs. native vegetation in the lower-middle reaches of the lancang-meikong river watershed, china

    International Nuclear Information System (INIS)

    Ou, G.L.; Ma, H.C.; Tang, J.R.


    22 plots at the Xiaoheijiang base, located in the lower-middle reaches of the Lancang-Meikong River in China, were investigated to analyze the understory biodiversity of Jatropha curcas plantations. Two kinds of mixed modes of J. curcas (mixed plantation with Macadamia integrifolia and mixed plantation with shrub species) and a pure plantation of J. curcas were planted, while the native vegetation served as a control. The plots were distributed along the gradients of forest management, succession and elevation by CCA analysis. Species richness was not significantly different for the different types of plantation, but the evenness of species could be affected, especially for the total community and the understory by planting J. curcas. The diversity and evenness indices of species were affected for the mixed plantation with different proportions of M. integrifolia, especially for the shrub layer, the Shannon diversity index and Pilou evenness index showed significant differences. And for the different mixed shrub species, only the Shannon diversity index and Pilou evenness index were significantly different. Finally, from the perspective of biological diversity, J.curcas plantation with shrub species would be a recommended planting model for ecological restoration in a dry-hot valley area, while J. curcas plantation with M. integrifolia would be an effective planting model to balance crop yield and food security. (author)

  5. Riparian Vegetation Response to the March 2008 Short-Duration, High-Flow Experiment-Implications of Timing and Frequency of Flood Disturbance on Nonnative Plant Establishment Along the Colorado River Below Glen Canyon Dam (United States)

    Ralston, Barbara E.


    Riparian plant communities exhibit various levels of diversity and richness. These communities are affected by flooding and are vulnerable to colonization by nonnative species. Since 1996, a series of three high-flow experiments (HFE), or water releases designed to mimic natural seasonal flooding, have been conducted at Glen Canyon Dam, Ariz., primarily to determine the effectiveness of using high flows to conserve sediment, a limited resource. These experiments also provide opportunities to examine the susceptibility of riparian plant communities to nonnative species invasions. The third and most recent HFE was conducted from March 5 to 9, 2008, and scientists with the U.S. Geological Survey's Grand Canyon Monitoring and Research Center examined the effects of high flows on riparian vegetation as part of the overall experiment. Total plant species richness, nonnative species richness, percent plant cover, percent organic matter, and total carbon measured from sediment samples were compared for Grand Canyon riparian vegetation zones immediately following the HFE and 6 months later. These comparisons were used to determine if susceptibility to nonnative species establishment varied among riparian vegetation zones and if the timing of the HFE affected nonnative plant establishment success. The 2008 HFE primarily buried vegetation rather than scouring it. Percent nonnative cover did not differ among riparian vegetation zones; however, in the river corridor affected by Glen Canyon Dam operations, nonnative species richness showed significant variation. For example, species richness was significantly greater immediately after and 6 months following the HFE in the hydrologic zone farthest away from the shoreline, the area that represents the oldest riparian zone within the post-dam riparian area. In areas closer to the river channel, tamarisk (Tamarix ramosissima X chinensis) seedling establishment occurred (tamarisk seed production, or in 1986, a year following several

  6. How Saharan Dust Slows River Knickpoints: Coupling Vegetation Canopy, Soils and the Foundation of the Critical Zone (United States)

    Brocard, G. Y.; Willenbring, J. K.; Harrison, E. J.; Scatena, F. N.


    Forest succession theory maintains that trees drape existing landscapes as passive niche optimizers, but in the Luquillo Mountains in Puerto Rico, the forest exerts a powerful control on erosion. The Luquillo Critical Zone observatory is set in the Luquillo Mountains, an isolated massif at the northeastern tip of Puerto Rico Island which receives up to five meters of rainfall annually. Most of the rainfall received in the mountains is conveyed as quick flow through soil macropores, inhibiting soil erosion by overland flow. Physical erosion is kept low, occurring in the form of infrequent shallow landslides, thus increasing the residence time of minerals in the near-surface environment. The extensive chemical alteration of minerals generates a thick saprolite covered by fine-grained soil. Over the quartz diorite bedrock that characterizes the southern side of the mountains, the weathering process generates saprolite tens of meters deep that is almost completely devoid of weatherable minerals. Soils forming over this saprolite are nutrient-poor, forcing the rainforest to retrieve its nutrients from atmospheric fluxes, such as Saharan dust and marine aerosols. These atmospheric inputs are thus indirectly essential for the forest to be able to maintain slow erosion rates over the mountains. At lower elevation, using cosmogenic nuclide-derived denudation rates, we identified a wave of incision which has been propagating upstream over the past 4 My in the form of very steep and slowly migrating knickpoints. Bedrock abrasion and plucking are infrequent along the knickpoint faces, because the bedrock is massive and because rivers are bedload-starved. This situation is due to the highly weathered upland soils and slow erosion rates and high weathering rate upstream, which acts to reduce bedload grain size and limits bedload fluxes to the knickpoint, respectively. The soils change radically where the wave of erosion has passed and has increased erosion rates. There, nutrient

  7. Relationship of weed shiner and young-of-year bluegill and largemouth bass abundance to submersed aquatic vegetation in Navigation Pools 4, 8, and 13 of the Upper Mississippi River, 1998-2012 (United States)

    DeLain, Steven A.; Popp, Walter A.


    Aquatic vegetation provides food resources and shelter for many species of fish. This study found a significant relationship between increases in submersed aquatic vegetation (SAV) in four study reaches of the Upper Mississippi River (UMR) and increases in catch-per-unit-effort (CPUE) of weed shiners (Notropis texanus) and age-0 bluegills (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) when all of the study reaches were treated collectively using Long Term Resource Monitoring Program (LTRMP) vegetation and fish data for 1998–2012. The selected fishes were more abundant in study reaches with higher SAV frequencies (Pool 8 and Lower Pool 4) and less abundant in reaches with lower SAV frequencies (Pool 13 and Upper Pool 4). When each study reach was examined independently, the relationship between SAV frequency and CPUE of the three species was not significant in most cases, the primary exception being weed shiners in Lower Pool 4. Results of this study indicate that the prevalence of SAV does affect relative abundance of these vegetation-associated fish species. However, the poor annual relationship between SAV frequency and age-0 relative abundance in individual study reaches indicates that several other factors also govern age-0 abundance. The data indicate that there may be a SAV frequency threshold in backwaters above which there is not a strong relationship with abundance of these fish species. This is indicated by the high annual CPUE variability of the three selected fishes in backwaters of Pool 8 and Lower Pool 4 when SAV exceeded certain frequencies.

  8. Medium Scale Central Valley Riparian Vegetation and Land Use with Aggregated Delta Veg, 2011 [ds724 (United States)

    California Natural Resource Agency — Geodatabase (SDE) feature class containing map of vegetation along mainstem rivers and major tributaries (including ancillary natural and semi-natural vegetation)...

  9. Impacts of a heavy storm of rain upon dissolved and particulate organic C, N and P in the main river of a vegetation-rich basin area in Japan. (United States)

    Li, Fusheng; Yuasa, Akira; Muraki, Yuzo; Matsui, Yoshihiko


    The impacts of a heavy storm of rain upon the dissolved and particulate organic matter (OM), nitrogen (N) and phosphorus (P) in the main river of the vegetation-rich Nagara River basin were investigated using water samples collected along the river line during a critical typhoon-induced heavy rain storm event. Besides, based on a high performance size-exclusion chromatography (HPSEC) system, the variance of dissolved OM (DOM) in its molecular weight (MW) characteristics was also assessed. From the MW standpoint, DOM components merged into the river along the river line resembled those present in its headwater. The MW range changed only slightly from 1010 to 5900 at the upstream (US), to 1130-5900 and 1200-5900 Da at the midstream (MS) and downstream (DS), respectively, while the corresponding weight-averaged MW (M(w)) decreased from 3669 to 3330 and 2962 Da. The heavy storm of rain enhanced the content of DOM; however, apart from a small larger-MW fraction (about 5900-6800 Da), the newly emerged DOM constituents exhibited an MW range similar to those existed before the storm. Due also to the storm of rain, total P and N (TP and TN) changed markedly in the ranges of 6.6-11.9, 8.3-40.6 and 48.4-231.3 microg/l for TP, and 145.4-296.0, 502.2-1168.7 and 1342.7-1927.3 microg/l for TN at the US, MS and DS, respectively. The larger values of TP and TN generally appeared for samples at elevated river water levels. The enhanced presence of P was found largely attributed to its particulate form; while, for N, the contribution from its dissolved form was significant. The newly emerged suspended particles via the storm-water contained lower content of OM, N and P, and a general decreasing trend of the particulate OM, N and P along the river line was also confirmed. The C/N ratio in the dissolved form varied in 0.7-6.7 and decreased downstream, while, that in the particulate form 2.3-17.3. Suspended particles that emerged in the river water during the storm exhibited larger C

  10. Determining Regional Actual Evapotranspiration of Irrigated Crops and Natural Vegetation in the São Francisco River Basin (Brazil Using Remote Sensing and Penman-Monteith Equation

    Directory of Open Access Journals (Sweden)

    Antônio H. de C. Teixeira


    Full Text Available To achieve sustainable development and to ensure water availability in hydrological basins, water managers need tools to determine the actual evapotranspiration (ET on a large scale. Field energy balances from irrigated and natural ecosystems together with a net of agro-meteorological stations were used to develop two models for ET quantification at basin scale, based on the Penman-Monteith equation. The first model (PM1 uses the resistances to the latent heat fluxes estimated from satellite measurements, while the second one (PM2 is based on the ratio of ET to the reference evapotranspiration (ET0 and its relation to remote sensing parameters. The models were applied in the Low-Middle São Francisco river basin in Brazil and, after comparison against field results, showed good agreements with PM1 and PM2 explaining, respectively, 79% and 89% of the variances and mean square errors (RMSE of 0.44 and 0.34 mm d−1. Even though the PM1 model was not chosen for ET calculations, the equation for surface resistance (rs was applied to infer the soil moisture conditions in a simplified vegetation classification. The maximum values of rs were for natural vegetation—caatinga (average of 1,937 s m−1. Wine grape and mango orchard presented similar values around 130 s m−1, while table grape presented the lowest ones, averaging 74 s m−1. Petrolina and Juazeiro, in Pernambuco (PE and Bahia (BA states, respectively, were highlighted with the biggest irrigated areas. The highest increments are for vineyards and mango orchards. For the first crop the maximum increment was verified between 2003 and 2004 in Petrolina-PE, when the cultivated area increased 151%. In the case of mango orchards the most significant period was from 2005 to 2006 in Juazeiro-BA (129%. As the best performance was for PM2, it was selected and used to analyse the regional ET at daily and annual scales, making use of Landsat images and a geographic information system for different

  11. Observations of the vegetation of the Atigun River floodplain as affected by the crude oil spill from the Trans-Alaska Pipeline (United States)

    Department of the Interior — This report is a summary of the results of botanical investigation conducted along the Atigun River, associated side channels and tributaries during the period 26 –...

  12. Associations between fish assemblage and riparian vegetation in the Corumbataí River Basin (SP Associações entre assembléia de peixes e a mata ciliar na bacia do rio Corumbataí (SP

    Directory of Open Access Journals (Sweden)

    M. Cetra


    Full Text Available This work intends to examine if there are associations between fish species and the state of conservation of the riparian forest in the Corumbataí River Basin. Four main rivers were chosen for this study with three sites on each. Collections were carried out from March to June and from September to December 2001. Multivariate techniques were applied to determine the correlation between species richness and the order of the rivers, preservation level of the riparian forest, shade level, presence or absence of Eucalyptus, sugar cane and pastures, and surrounding declivity stability of the sites. Species richness was highest at locations with greater vegetation cover and preserved riparian forest.Este trabalho teve o objetivo de examinar se existem associações entre as espécies de peixes e o estado de conservação das matas ciliares na bacia do rio Corumbataí. Foram escolhidos 4 rios principais com 3 pontos de coleta em cada um. Foram realizadas coletas nos períodos de março a junho e de setembro a dezembro de 2001. Técnicas multivariadas foram aplicadas para determinar a correlação entre a riqueza de espécies e a ordem dos rios, estado de preservação da mata ciliar, sombreamento, presença ou ausência de Eucalyptus, cana-de-açúcar e pastagens, e nível de estabilidade do barranco ao redor dos pontos de coleta. A riqueza de espécies foi maior em locais com maior cobertura vegetal e mata ciliar preservada.

  13. Application and Comparison of the MODIS-Derived Enhanced Vegetation Index to VIIRS, Landsat 5 TM and Landsat 8 OLI Platforms: A Case Study in the Arid Colorado River Delta, Mexico (United States)

    Jarchow, Christopher J.; Didan, Kamel; Barreto-Muñoz, Armando; Glenn, Edward P.


    The Enhanced Vegetation Index (EVI) is a key Earth science parameter used to assess vegetation, originally developed and calibrated for the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra and Aqua satellites. With the impending decommissioning of the MODIS sensors by the year 2020/2022, alternative platforms will need to be used to estimate EVI. We compared Landsat 5 (2000–2011), 8 (2013–2016) and the Visible Infrared Imaging Radiometer Suite (VIIRS; 2013–2016) to MODIS EVI (2000–2016) over a 420,083-ha area of the arid lower Colorado River Delta in Mexico. Over large areas with mixed land cover or agricultural fields, we found high correspondence between Landsat and MODIS EVI (R2 = 0.93 for the entire area studied and 0.97 for agricultural fields), but the relationship was weak over bare soil (R2 = 0.27) and riparian vegetation (R2 = 0.48). The correlation between MODIS and Landsat EVI was higher over large, homogeneous areas and was generally lower in narrow riparian areas. VIIRS and MODIS EVI were highly similar (R2 = 0.99 for the entire area studied) and did not show the same decrease in performance in smaller, narrower regions as Landsat. Landsat and VIIRS provide EVI estimates of similar quality and characteristics to MODIS, but scale, seasonality and land cover type(s) should be considered before implementing Landsat EVI in a particular area. PMID:29757265

  14. Changing landscape in the Three Gorges Reservoir Area of Yangtze River from 1977 to 2005: Land use/land cover, vegetation cover changes estimated using multi-source satellite data (United States)

    Zhang, Jixian; Zhengjun, Liu; Xiaoxia, Sun


    The eco-environment in the Three Gorges Reservoir Area (TGRA) in China has received much attention due to the construction of the Three Gorges Hydropower Station. Land use/land cover changes (LUCC) are a major cause of ecological environmental changes. In this paper, the spatial landscape dynamics from 1978 to 2005 in this area are monitored and recent changes are analyzed, using the Landsat TM (MSS) images of 1978, 1988, 1995, 2000 and 2005. Vegetation cover fractions for a vegetation cover analysis are retrieved from MODIS/Terra imagery from 2000 to 2006, being the period before and after the rising water level of the reservoir. Several analytical indices have been used to analyze spatial and temporal changes. Results indicate that cropland, woodland, and grassland areas reduced continuously over the past 30 years, while river and built-up area increased by 2.79% and 4.45% from 2000 to 2005, respectively. The built-up area increased at the cost of decreased cropland, woodland and grassland. The vegetation cover fraction increased slightly. We conclude that significant changes in land use/land cover have occurred in the Three Gorges Reservoir Area. The main cause is a continuous economic and urban/rural development, followed by environmental management policies after construction of the Three Gorges Dam.

  15. Análise das modificações da cobertura vegetal da planície fluvial do alto rio Paraná no período entre 1976 e 2007 = Analysis of vegetation changes in the Paraná river floodplain between 1976 and 2007

    Directory of Open Access Journals (Sweden)

    Edivando Vitor Couto


    Full Text Available A vegetação da planície fluvial do rio Paraná sofre a pressão da ocupação antrópica desde a década de 1950. A área próxima a Porto Rico (Paraná tem sido estudada desde os anos 1980, mas não há estudos dirigidos à distribuição espacial da vegetação. Os objetivos deste trabalho são cartografar as unidades vegetais e verificar a evolução temporal de sua distribuição entre 1976 e 2007. Para isso foram utilizadas imagens orbitais de 1976 (LANDSAT MSS-1, 1987 (LANDSAT TM-5, 2000 (LANDSAT ETM+7 e de 2007 (CBERS-2 CCD. Asimagens foram georreferenciadas e classificadas pelo algoritmo Bhattacharya. Foram identificadas três classes de vegetação, corpos de água e áreas de solo exposto. A análise multitemporal demonstrou aumento contínuo da área de solo exposto, aumento da área dos corpos de água, mudança de posição das áreas úmidas no período entre 1976 e 1987 e modificações mais sutis de ambas as classes no período entre 1987 e 2007. As áreas de vegetação arbórea diminuíram em quase todos os anos. Tais dados permitem afirmar que a atuação antrópica sobre a planície vem se ampliando e que as principais cheias modificaram sua morfologia.The removal of vegetation from the Paraná river floodplain has been increasing since the 1950s the until present time, but no study has been made about its spatial distribution. The purpose of this paper is to map and analyze the temporal evolution of vegetation distribution over the Parana river floodplain between 1976 and 2007. Orbital images from 1976 (LANDSAT MSS-1, 1987 (LANDSAT TM-5, 2000 (LANDSAT ETM+7 and 2007 (CBERS-2 CCD were utilized to compare the evolution of the vegetation distribution over that time period. Theimages were georeferenced using SPRING 4.3.3 software and classified by the Bhattacharya algorithm; the maps were produced using the Global Mapper 7.4 software. Three different classes of vegetation, water bodies and exposed soil areas were

  16. Advances on Modelling Riparian Vegetation-Hydromorphology Interactions

    NARCIS (Netherlands)

    Solari, L.; Van Oorschot, M.; Belletti, B.; Hendriks, D.; Rinaldi, M.; Vargas-Luna, A.


    Riparian vegetation actively interacts with fluvial systems affecting river hydrodynamics, morphodynamics and groundwater. These interactions can be coupled because both vegetation and hydromorphology (i.e. the combined scientific study of hydrology and fluvial geomorphology) involve dynamic

  17. Simulation of a rainfall - runoff process for the evaluation of variability in the river flow regime in small basins with vegetation changes

    Czech Academy of Sciences Publication Activity Database

    Buchtele, Josef; Tesař, Miroslav


    Roč. 41, - (2010), s. 103-110 ISSN 0071-6715 R&D Projects: GA MŽP(CZ) SP/1A6/151/07 EU Projects: European Commission(XE) 511179 - NEWATER Institutional research plan: CEZ:AV0Z20600510 Keywords : vegetation change * land use * rainfall - runoff simulation * evapotranspiration demand Subject RIV: DA - Hydrology ; Limnology

  18. Natural Setting and Vegetation of the Florida Panhandle. An Account of the Environments and Plant Communities of Northern Florida, West of the Suwannee River. (United States)


    burrowers in the panhandle are moles, mice, shrews, cotton rats, pocket gophers, gopher turtles , crayfish, ants, and earthworms. . The detrital feeders...applicability of the terms, primeval, original, and virgin for our vegetation suddenly becomes nebulous . ., l Nonetheless there remains an obvious...mechanism for soil disturbance in wiregrass lands with the possible exception of the burrowing of gopher turtles . Anthesis occurs 5-9 months following

  19. Coupling legacy geomorphic surface facies to riparian vegetation: Assessing red cedar invasion along the Missouri River downstream of Gavins Point dam, South Dakota (United States)

    Greene, Samantha L.; Knox, James C.


    Floods increase fluvial complexity by eroding established surfaces and creating new alluvial surfaces. As dams regulate channel flow, fluvial complexity often decreases and the hydro-eco-geomorphology of the riparian habitat changes. Along the Missouri River, flow regulation resulted in channel incision of 1-3 m within the study area and disconnected the pre-dam floodplain from the channel. Evidence of fluvial complexity along the pre-dam Missouri River floodplain can be observed through the diverse depositional environments represented by areas of varying soil texture. This study evaluates the role of flow regulation and depositional environment along the Missouri River in the riparian invasion of red cedar downstream of Gavins Point dam, the final dam on the Missouri River. We determine whether invasion began before or after flow regulation, determine patterns of invasion using Bayesian t-tests, and construct a Bayesian multivariate linear model of invaded surfaces. We surveyed 59 plots from 14 riparian cottonwood stands for tree age, plot composition, plot stem density, and soil texture. Red cedars existed along the floodplain prior to regulation, but at a much lower density than today. We found 2 out of 565 red cedars established prior to regulation. Our interpretation of depositional environments shows that the coarser, sandy soils reflect higher energy depositional pre-dam surfaces that were geomorphically active islands and point bars prior to flow regulation and channel incision. The finer, clayey soils represent lower energy depositional pre-dam surfaces, such as swales or oxbow depressions. When determining patterns of invasion for use in a predictive statistical model, we found that red cedar primarily establishes on the higher energy depositional pre-dam surfaces. In addition, as cottonwood age and density decrease, red cedar density tends to increase. Our findings indicate that flow regulation caused hydrogeomorphic changes within the study area that

  20. Delta Vegetation and Land Use [ds292 (United States)

    California Natural Resource Agency — Vegetation and land use are mapped for the approximately 725,000 acres constituting the Legal Delta portion of the Sacramento and San Joaquin River Delta area....

  1. Generic index of aquatic vegetation (IVAM) for a rapid assessment of ecological quality of Spanish rivers: taxonomic resolution and application to Castilla-La Mancha region; Indice Generico de Vegetacion Acuatica (IVAM): Propuesta de evaluacion rapida del estado ecologico de los rios ibericos en aplicacion de la Directiva Marco del Agua

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, J. L.; Navarro, C.; Hera, J. de las


    The Water Framework Directive proposes the use of aquatic flora as a valid bio indicator for assessing the ecological status of European rivers. Due to the lack of an aquatic vegetation index for Spanish rivers, we present an index to assess trophic status or eutrophication in rivers and streams. Thus, we calculated tolerance scores and indicator values for tax from nutrient levels. the index is called IVAM (Macroscopic Aquatic Vegetation Index). The index takes into account either macrophyte or microphytes (the latter making up macroscopic growth forms) including briophytes. The IVAM showed the best correlation with nutrients besides other quality indices, indicating a solid tool to assess trophic status or eutrophication. (Author) 15 refs.

  2. Análise espaço-temporal da cobertura vegetal e uso da terra na Interbacia do Rio Paraguai Médio-MT, Brasil Spatio-temporal analysis of vegetation cover and land use in the middle Paraguay River Interbasin-MT, Brazil

    Directory of Open Access Journals (Sweden)

    Seyla Poliana Miranda Pessoa


    Full Text Available O objetivo deste estudo foi realizar uma análise espaço-temporal da cobertura vegetal e do uso da terra na Interbacia do Rio Paraguai Médio-MT, Brasil, pelo geoprocessamento de imagens Landsat TM, dos anos 1991, 2001 e 2011. As imagens foram georreferenciadas, classificadas e processadas no software Spring e as classes temáticas, quantificadas e editadas no software ArcGis. Foram mapeadas sete classes, sendo as mais expressivas a vegetação nativa, a pastagem e a cana-de-açúcar. Os resultados indicaram alterações em todas as classes durante os últimos 20 anos, com a diminuição de 22,89% da vegetação nativa, relacionada com o aumento de 58,42% da pastagem e 490,26% de monocultura de cana-de-açúcar. Foi verificado o conflito de uso da terra, principalmente em áreas de mata ciliar, fato que pode influenciar negativamente na conservação da interbacia e, consequentemente, do pantanal mato-grossense.This study analyzed spatial and temporal land use changes in the Middle Paraguay River Interbasin-MT, Brazil using Landsat images from 1991, 2001 and 2011. Images were geo-referenced, classified and processed using Spring software, and thematic classes were edited and quantified using ArcGis software. Seven map classes were identified, and native vegetation, pasture and sugarcane were the most significant ones. The results showed changes in all classes during the past 20 years, primarily a 22.89% decrease of native vegetation, a 58.42% increase in pasture and 490.26% increase of sugarcane monoculture. We verified land use conflicts, mostly in riparian areas, which may negatively influence Interbasin and, consequently, Pantanal conservation in the State of Mato Grosso, Brazil.

  3. Kuchler Vegetation (United States)

    California Natural Resource Agency — Digital version of potential natural plant communites as compiled and published on 'Map of the Natural Vegetation of California' by A. W. Kuchler, 1976. Source map...

  4. Wieslander Vegetation (United States)

    California Natural Resource Agency — Digital version of the 1945 California Vegetation Type Maps by A. E. Wieslander of the U.S. Forest Service. Source scale of maps are 1:100,000. These compiled maps...

  5. Conveyance estimation in channels with emergent bank vegetation ...

    African Journals Online (AJOL)

    Emergent vegetation along the banks of a river channel influences its conveyance considerably. The total channel discharge can be estimated as the sum of the discharges of the vegetated and clear channel zones calculated separately. The vegetated zone discharge is often negligible, but can be estimated using ...

  6. Wetland vegetation establishment in L-Lake

    International Nuclear Information System (INIS)

    Kroeger, S.R.


    Wetland vegetation was transplanted from PAR Pond to L-Lake between January and August, 1987. Approximately 100,000 individual plants representing over 40 species were transplanted along the southern shoreline. Three zones of vegetation were created: (1) submersed/floating-leaved, (2) emergent, (3) upper emergent/shrub. During the summers of 1987, 1988, 1989, the Savannah River Ecology Laboratory sampled the vegetation in 54 permanent transects located in planted (N=32) and unplanted areas (N=22). The 1989 vegetation data from L-Lake were compared to 1985 data from PAR Pond


    Directory of Open Access Journals (Sweden)



    Full Text Available The current work examines the main aspects of wetland vegetation mapping, which can be summarized as analysis of the ecological-vegetational (ecotone gradients; vegetation complexes; relationships between vegetation distribution and geomorphology; vegetation of the hydrographic basin lo which the wetland in question belongs; vegetation monitoring with help of four vegetation maps: phytosociological map of the real and potential vegetation, map of vegetation dynamical tendencies, map of vegetation series.

  8. Vegetative regeneration (United States)

    George A. Schier; John R. Jones; Robert P. Winokur


    Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

  9. Understory vegetation (United States)

    Steve Sutherland; Todd F. Hutchinson; Jennifer L. Windus


    This chapter documents patterns of species composition and diversity within the understory vegetation layer and provides a species list for the four study areas in southern Ohio. Within each of 108 plots, we recorded the frequency of all vascular plant species in sixteen 2-m² quadrats. We recorded 297 species, including 187 forbs (176 perennials, 9 annuals, 2...

  10. 1998 Annual Status Report: Status and Trend of Submersed and Floating-leaved Aquatic Vegetation in Thirty-two Backwaters in Pools 4, 8, 13, and 26 and La Grange Pool of the Upper Mississippi River System

    National Research Council Canada - National Science Library

    Yin, Yao


    .... The status and trend of aquatic vegetation in 1998 varied among the thirty-two backwaters. In upper Pool 4 (above Lake Pepin), where aquatic vegetation has declined since 1991, the trend continued in 1998...

  11. The contribution of vegetation to riverbed morphology (Invited) (United States)

    Bertoldi, W.; Gurnell, A. M.


    The occurrence, form and species composition of riparian and aquatic vegetation are all strongly affected by the flow energy regime, sediment calibre and dimensions of river systems. In this paper, we build on field examples to conceptualise how interactions between vegetation and fluvial processes may affect river form across a gradient of river types from high-energy gravel-bed braided rivers to lowland single-thread silt-bed rivers. We explore how different vegetation types (e.g. riparian trees, shrubs, emergent macrophytes), and in some cases particular plant species, can produce similar impacts on the bed topography of rivers of different size, because of their effect on sediment transport flux and sediment cohesion, and a resultant positive feedback that increases the bar or bank height. We illustrate these concepts using two case studies representing extremes of river size and energy. Field and remotely sensed data are used to identify and quantify impacts of vegetation density on the bed morphology of the >1km wide, gravel-bed, braided Tagliamento River (Italy). Analysis of airborne LiDAR data is used to compute a highly detailed digital elevation model, along with data on tree height and density. The comparison between reaches with different tree height and density clearly shows the active role of vegetation in determining river pattern and form, with tree growth rate being the main parameter determining the vegetation effect. Analysis of field measurements of flow patterns and mechanical properties of emergent aquatic macrophytes on the <10m wide, silt-bed, single-thread River Blackwater (England) illustrate the close correspondence of the bed topography with vegetation structures, with position along an energy gradient dictating changes in the structure of the vegetation-bed morphology interaction.

  12. componente vegetal

    Directory of Open Access Journals (Sweden)

    Fabio Moscovich


    Full Text Available In order to determine environmental impact, indicators based on vegetation characteristics that would generate the forestry monoculture with the adjacent native forest, 32 sample unit were installed in an area of LIPSIA private enterprise, Esperanza Department, Misiones with those characteristics. The plots of 100 m2 were distributed systematically every 25 meters. The vegetation was divided in stratum: superior (DBH ≥ 10 cm, middle (1,6 cm ≤ DBH > 10 cm and inferior (DBH< cm. There were installed 10 plots in a logged native forest, 10 plots in a 18 years old Pinus elliottii Engelm. with approximately 400 trees/ha., 6 plots in a 10 – 25 years old Araucaria angustifolia (Bertd. Kuntze limiting area with approximately 900 trees/ha., and 6 plots located in this plantation. In the studied area were identified 150 vegetation species. In the inferior stratum there were found differences as function of various floristic diversity indexes. In all the cases the native forest showed larger diversity than plantations, followed by Pinus elliottii, Araucaria plantation and Araucaria limiting area. All the studied forest fitted to a logarithmical series of species distributions, that would indicate the incidence of a environmental factor in this distribution.

  13. Sensitivity Analysis of a Riparian Vegetation Growth Model

    Directory of Open Access Journals (Sweden)

    Michael Nones


    Full Text Available The paper presents a sensitivity analysis of two main parameters used in a mathematic model able to evaluate the effects of changing hydrology on the growth of riparian vegetation along rivers and its effects on the cross-section width. Due to a lack of data in existing literature, in a past study the schematization proposed here was applied only to two large rivers, assuming steady conditions for the vegetational carrying capacity and coupling the vegetal model with a 1D description of the river morphology. In this paper, the limitation set by steady conditions is overcome, imposing the vegetational evolution dependent upon the initial plant population and the growth rate, which represents the potential growth of the overall vegetation along the watercourse. The sensitivity analysis shows that, regardless of the initial population density, the growth rate can be considered the main parameter defining the development of riparian vegetation, but it results site-specific effects, with significant differences for large and small rivers. Despite the numerous simplifications adopted and the small database analyzed, the comparison between measured and computed river widths shows a quite good capability of the model in representing the typical interactions between riparian vegetation and water flow occurring along watercourses. After a thorough calibration, the relatively simple structure of the code permits further developments and applications to a wide range of alluvial rivers.

  14. Groundwater controls on river channel pattern (United States)

    Bätz, Nico; Colombini, Pauline; Cherubini, Paolo; Lane, Stuart N.


    Braided rivers are characterized by high rates of morphological change. However, despite the potential for frequent disturbance, vegetated patches may develop within this system and influence long-term channel dynamics and channel patterns through the "engineering effects" of vegetation. The stabilizing effect of developing vegetation on morphological change has been widely shown by flume experiments and (historic) aerial pictures analysis. Thus, there is a balance between disturbance and stabilization, mediated through vegetation, that may determine the long-term geomorphic and biogeomorphic evolution of the river. It follows that with a change in disturbance frequency relative to the rate of vegetation establishment, a systematic geomorphological shift could occur. Research has addressed how changes in disturbance frequency affect river channel pattern, but has rarely addressed the way in which the stabilizing effects of biogeomorphic succession interact with disturbance frequency to maintain a river in a more dynamic or a less dynamic state. Here, we quantify how the interplay between groundwater access, disturbance frequency and vegetation succession, drive changes in channel pattern. We studied this complex interplay on a transitional gravel-bed river system (braided, wandering, meandering) close to Geneva (Switzerland) - the Allondon River. Dendroecological analysis demonstrate that vegetation growth is driven by groundwater access. Groundwater access conditions the rate of vegetation stabilization at the sub-reach scale and, due to a reduction in flood-related disturbance frequency over the last 50 years, drives a change in channel pattern. Where groundwater is shallower, vegetation encroachment rates were high and as flood-related disturbance decreased, the river has shifted towards a meandering state. Where groundwater was deeper, vegetation growth was limited by water-access and thus vegetation encroachment rates were low. Even though there was a

  15. Assessment of cobalt levels in wastewater, soil and vegetable ...

    African Journals Online (AJOL)


    Key words: Cobalt level, Kubanni River, soil, vegetable, wastewater. INTRODUCTION. Cobalt is ... metals released into the environment from a variety of anthropogenic activities ..... Heavy Metal Stress in Plants, 2nd Edition,. Springer,. United.

  16. Climate influences on upper Limpopo River flow

    African Journals Online (AJOL)


    Jan 1, 2016 ... Keywords: Limpopo Valley, hydro-meteorology, surface water deficit. * To whom all ... millenia and there is a history of drought impacts on vegetation. (Ekblom et ... water budget of the upper Limpopo River valley using direct.

  17. Phytostabilization of metals by indigenous riparian vegetation ...

    African Journals Online (AJOL)

    When measured against an ideal hypothetical buffer zone, the buffer zones under investigation varied between intact and severely compromised. Intact riparian zones showed elevated metal concentrations in the soil, yet significantly lower concentrations in the river water compared to areas with insufficient vegetative cover ...

  18. Classification of floodplain vegetation by data fusion of spectral (CASI) and LiDAR data

    NARCIS (Netherlands)

    Geerling, G.W.; Labrador-Garcia, M.; Clevers, J.G.P.W.; Ragas, A.M.J.; Smits, A.J.M.


    To safeguard the goals of flood protection and nature development, a river manager requires detailed and up-to-date information on vegetation structures in floodplains. In this study, remote-sensing data on the vegetation of a semi-natural floodplain along the river Waal in the Netherlands were

  19. River engineering

    NARCIS (Netherlands)

    De Vries, M.


    One dimension models - basic eauations, analytical models, numberical models. One dimensional models -suspended load, roughness and resistance of river beds. Solving river problems - tools, flood mitigation, bank protection.

  20. Lake Bathymetric Aquatic Vegetation (United States)

    Minnesota Department of Natural Resources — Aquatic vegetation represented as polygon features, coded with vegetation type (emergent, submergent, etc.) and field survey date. Polygons were digitized from...

  1. Summary of Vegetation Changes on Dredged Material and Environmental Management Program Sites in the St. Paul District, Corps of Engineers

    National Research Council Canada - National Science Library

    Anfang, Robert


    This report summaries the results of vegetation monitoring activities on dredged material placement sites on the Upper Mississippi River between Minneapolis, Minnesota and Prairie du Chien, Wisconsin...

  2. Análise da estrutura e da diversidade de uma vegetação ciliar do rio São Francisco, Petrolina–PE. Structure and diversity analysis of a São Francisco river banks vegetation, Petrolina–PE.

    Directory of Open Access Journals (Sweden)

    Silvana Cristina Pereira Muniz de SOUZA


    phytosociological survey was done on a disturbed river bank vegetation of São Francisco river, inside the Bebedouro Irrigation Project, Petrolina–PE. Five transects perpendicular to the river course were installed, composed with seven plots, with exception of one transect with three plots, of 8 m x 25 m (200 m², a total of 27 plots or 0.54 ha. The adults and the regenerating individuals were measured. We found 853 individual from 32 species. The richest family was Fabaceae and the richest gender was Mimosa. The density was 1,376 ind.ha , where the greatest contribution was fromthe regenerating individuals. The species with the greatest VI was Poeppigia procera fowled by Inga Vera. The adult strata showed higher diversity than regenerating strata. The topographic environmental Riverside was the one that had the greatest diversity and structure close to undisturbed vegetation. Despite the perturbation the studied vegetation showed values of richness and diversity consistent with well preserved vegetations. We concluded that beside the perturbation the river bank vegetation was able to support a great potential of self-recovering and still can perform their role as a high diversity keeper.

  3. Restoring Oaks in the Missouri River Floodplain (United States)

    Dan Dey; John Kabrick; Jennifer Grabner; Mike Gold


    Restoration of native vegetation and hydrologic regimes in the Mississippi and Missouri River floodplains is problematic because they are among the most altered ecosystems in North America (Noss et al. 1995), and because of the competing demands placed on these river ecosystems by commercial, private and social interests. Since the 1780s, more than half (53 percent) of...

  4. Soil-vegetation-atmosphere transfer modeling

    Energy Technology Data Exchange (ETDEWEB)

    Ikonen, J.P.; Sucksdorff, Y. [Finnish Environment Agency, Helsinki (Finland)


    In this study the soil/vegetation/atmosphere-model based on the formulation of Deardorff was refined to hour basis and applied to a field in Vihti. The effect of model parameters on model results (energy fluxes, temperatures) was also studied as well as the effect of atmospheric conditions. The estimation of atmospheric conditions on the soil-vegetation system as well as an estimation of the effect of vegetation parameters on the atmospheric climate was estimated. Areal surface fluxes, temperatures and moistures were also modelled for some river basins in southern Finland. Land-use and soil parameterisation was developed to include properties and yearly variation of all vegetation and soil types. One classification was selected to describe the hydrothermal properties of the soils. Evapotranspiration was verified against the water balance method

  5. Soil-vegetation-atmosphere transfer modeling

    Energy Technology Data Exchange (ETDEWEB)

    Ikonen, J P; Sucksdorff, Y [Finnish Environment Agency, Helsinki (Finland)


    In this study the soil/vegetation/atmosphere-model based on the formulation of Deardorff was refined to hour basis and applied to a field in Vihti. The effect of model parameters on model results (energy fluxes, temperatures) was also studied as well as the effect of atmospheric conditions. The estimation of atmospheric conditions on the soil-vegetation system as well as an estimation of the effect of vegetation parameters on the atmospheric climate was estimated. Areal surface fluxes, temperatures and moistures were also modelled for some river basins in southern Finland. Land-use and soil parameterisation was developed to include properties and yearly variation of all vegetation and soil types. One classification was selected to describe the hydrothermal properties of the soils. Evapotranspiration was verified against the water balance method

  6. Sorting out river channel patterns

    NARCIS (Netherlands)

    Kleinhans, M.G.


    Rivers self-organize their pattern/planform through feedbacks between bars, channels, floodplain and vegetation, which emerge as a result of the basic spatial sorting process of wash load sediment and bed sediment. The balance between floodplain formation and destruction determines the width and

  7. River habitat assessment for ecological restoration of Wei River Basin, China. (United States)

    Yang, Tao; Wang, Shuo; Li, Xiaoping; Wu, Ting; Li, Li; Chen, Jia


    As an important composition component of river ecosystems, river habitats must undergo quality assessment to potentially provide scientific basis for river ecological restoration. Substrate composition, habitat complexity, bank erosion degree, river meandering degree, human activity intensity, vegetation buffer width, water quality, and water condition were determined as indicators for river habitat assessment. The comprehensive habitat quality index (CHQI) was established for the Wei River Basin. In addition, the indicator values were determined on the basis of a field investigation at 12 national hydrological stations distributed across the Wei, Jing, and Beiluo Rivers. The analytic hierarchy process was used to determine the indicator weights and thus distinguish the relative importance of the assessment indicator system. Results indicated that the average CHQIs for the Wei, Jing, and Beiluo Rivers were 0.417, 0.508, and 0.304, respectively. The river habitat quality for the three rivers was well. As for the whole river basin, the river habitat quality for 25% of the cross section was very well, the other 25% was well, and the 50% remaining was in critical state. The river habitat quality of the Jing River was better than that of the Wei and Beiluo Rivers.

  8. Vegetation dynamics and dynamic vegetation science

    NARCIS (Netherlands)

    Van der Maarel, E


    his contribution presents a review of the development of the study of vegetation dynamics since 1979, in the framework of a jubilee meeting on progress in the study of vegetation. However, an exhaustive review is both impossible and unnecessary. It is impossible within the few pages available

  9. Charles River (United States)

    Information on the efforts of the US EPA, the Commonwealth of Massachusetts, the municipalities within the Charles River Watershed and nongovernmental organizations to improve the water quality of the Charles River.

  10. Fruits and vegetables (image) (United States)

    A healthy diet includes adding vegetables and fruit every day. Vegetables like broccoli, green beans, leafy greens, zucchini, cauliflower, cabbage, carrots, and tomatoes are low in calories and high in fiber, vitamins, and minerals. ...

  11. Vegetable Production System (Veggie) (United States)

    National Aeronautics and Space Administration — The Vegetable Production System (Veggie) was developed to be a simple, easily stowed, high growth volume, low resource facility capable of producing fresh vegetables...

  12. Características sedimentares fluviais associadas ao grau de reservação da mata Ciliar - Rio Urumajó, Nordeste Paraense Fluvial sedimentology associated with the degree of preservation of the riparian vegetation, Urumajó River, PA / Brazil

    Directory of Open Access Journals (Sweden)

    Roney Nonato Reis de Brito


    Full Text Available Os rios são os agentes mais importantes no transporte dos sedimentos para as áreas mais baixas dos continentes e para o mar. Além dos efeitos diretos do clima local, a cobertura vegetal atua no controle da descarga e no suprimento de sedimentos. Sendo assim, o presente trabalho enfoca o padrão de distribuição granulométrica do rio Urumajó (nordeste paraense em relação ao estado de preservação da mata ciliar. Cinco estações (A-E foram estabelecidas de forma a registrar um transecto da nascente à foz do rio. Nessas estações, procedeu-se com a caracterização da mata ciliar, bem como do seu grau de preservação. Além disto, elaborou-se um perfil transversal ao canal para cada estação, com coleta de cinco amostras de sedimentos em cada perfil. Estes foram submetidos à análise granulométrica, que resultou na obtenção de valores da média, mediana, seleção, assimetria e curtose. Com os resultados foi possível reconhecer as características sedimentares normais do rio, onde areia média é a principal classe granulométrica transportada. Foram observadas nas estações A e C a clara tendência das amostras serem moderadamente bem selecionadas e aproximadamente simétricas, com dominância absoluta de areia média, o que está diretamente relacionado ao seu bom estado de preservação. Significativas variações granulométricas nas estações B, D e E foram associadas com o processo erosivo das margens do rio, conseqüência da degradação da mata ciliar. Além disso, foi constatada a influência das correntes de maré na sedimentologia da estação E, subsidiando também a delimitação do ambiente estuarino que se encontra associado ao canal fluvial.Rivers are the main ways of sediment transport from inland to the coastal zone and oceans. Despite direct influence of climate, the vegetation coverage plays a central role in liquid and solid fluvial discharge. In this context, the present work aimed to study the fluvial

  13. European Vegetation Archive (EVA)

    NARCIS (Netherlands)

    Chytrý, Milan; Hennekens, S.M.; Jiménez-Alfaro, Borja; Schaminée, J.H.J.; Haveman, Rense; Janssen, J.A.M.


    The European Vegetation Archive (EVA) is a centralized database of European vegetation plots developed by the IAVS Working Group European Vegetation Survey. It has been in development since 2012 and first made available for use in research projects in 2014. It stores copies of national and

  14. Vegetation Description, Rare Plant Inventory, and Vegetation Monitoring for Craig Mountain, Idaho.

    Energy Technology Data Exchange (ETDEWEB)

    Mancuso, Michael; Moseley, Robert


    The Craig Mountain Wildlife Mitigation Area was purchased by Bonneville Power Administration (BPA) as partial mitigation for wildlife losses incurred with the inundation of Dworshak Reservoir on the North Fork Clearwater River. Upon completion of the National Environmental Protection Act (NEPA) process, it is proposed that title to mitigation lands will be given to the Idaho Department of Fish and Game (IDFG). Craig Mountain is located at the northern end of the Hells Canyon Ecosystem. It encompasses the plateau and steep canyon slopes extending from the confluence of the Snake and Salmon rivers, northward to near Waha, south of Lewiston, Idaho. The forested summit of Craig Mountain is characterized by gently rolling terrain. The highlands dramatically break into the canyons of the Snake and Salmon rivers at approximately the 4,700 foot contour. The highly dissected canyons are dominated by grassland slopes containing a mosaic of shrubfield, riparian, and woodland habitats. During the 1993 and 1994 field seasons, wildlife, habitat/vegetation, timber, and other resources were systematically inventoried at Craig Mountain to provide Fish and Game managers with information needed to draft an ecologically-based management plan. The results of the habitat/vegetation portion of the inventory are contained in this report. The responsibilities for the Craig Mountain project included: (1) vegetation data collection, and vegetation classification, to help produce a GIS-generated Craig Mountain vegetation map, (2) to determine the distribution and abundance of rare plants populations and make recommendations concerning their management, and (3) to establish a vegetation monitoring program to evaluate the effects of Fish and Game management actions, and to assess progress towards meeting habitat mitigation goals.

  15. Vegetation description, rare plant inventory, and vegetation monitoring for Craig Mountain, Idaho

    International Nuclear Information System (INIS)

    Mancuso, M.; Moseley, R.


    The Craig Mountain Wildlife Mitigation Area was purchased by Bonneville Power Administration (BPA) as partial mitigation for wildlife losses incurred with the inundation of Dworshak Reservoir on the North Fork Clearwater River. Upon completion of the National Environmental Protection Act (NEPA) process, it is proposed that title to mitigation lands will be given to the Idaho Department of Fish and Game (IDFG). Craig Mountain is located at the northern end of the Hells Canyon Ecosystem. It encompasses the plateau and steep canyon slopes extending from the confluence of the Snake and Salmon rivers, northward to near Waha, south of Lewiston, Idaho. The forested summit of Craig Mountain is characterized by gently rolling terrain. The highlands dramatically break into the canyons of the Snake and Salmon rivers at approximately the 4,700 foot contour. The highly dissected canyons are dominated by grassland slopes containing a mosaic of shrubfield, riparian, and woodland habitats. During the 1993 and 1994 field seasons, wildlife, habitat/vegetation, timber, and other resources were systematically inventoried at Craig Mountain to provide Fish and Game managers with information needed to draft an ecologically-based management plan. The results of the habitat/vegetation portion of the inventory are contained in this report. The responsibilities for the Craig Mountain project included: (1) vegetation data collection, and vegetation classification, to help produce a GIS-generated Craig Mountain vegetation map, (2) to determine the distribution and abundance of rare plants populations and make recommendations concerning their management, and (3) to establish a vegetation monitoring program to evaluate the effects of Fish and Game management actions, and to assess progress towards meeting habitat mitigation goals

  16. Potential plant species distribution in the Yellow River Delta under the influence of groundwater level and soil salinity

    NARCIS (Netherlands)

    Fan Xiaomei,; Pedroli, B.; Liu Gaohuan,; Liu Hongguang,; Song Chuangye,; Shu Longcang,


    This article describes a multidisciplinary approach to assessing potential vegetation types. The relation between vegetation distribution as derived from field survey and habitat characteristics in the Yellow River Delta (YRD) was analyzed using detrended canonical correspondence analysis (DCCA).

  17. 75 FR 6364 - Process for Requesting a Variance From Vegetation Standards for Levees and Floodwalls (United States)


    ..., channels, or shore- line or river-bank protection systems such as revetments, sand dunes, and barrier...) toe (subject to preexisting right-of-way). f. The vegetation variance process is not a mechanism to...

  18. History of river regulation of the Noce River (NE Italy) and related bio-morphodynamic responses (United States)

    Serlet, Alyssa; Scorpio, Vittoria; Mastronunzio, Marco; Proto, Matteo; Zen, Simone; Zolezzi, Guido; Bertoldi, Walter; Comiti, Francesco; Prà, Elena Dai; Surian, Nicola; Gurnell, Angela


    The Noce River is a hydropower-regulated Alpine stream in Northern-East Italy and a major tributary of the Adige River, the second longest Italian river. The objective of the research is to investigate the response of the lower course of the Noce to two main stages of hydromorphological regulation; channelization/ diversion and, one century later, hydropower regulation. This research uses a historical reconstruction to link the geomorphic response with natural and human-induced factors by identifying morphological and vegetation features from historical maps and airborne photogrammetry and implementing a quantitative analysis of the river response to channelization and flow / sediment supply regulation related to hydropower development. A descriptive overview is presented. The concept of evolutionary trajectory is integrated with predictions from morphodynamic theories for river bars that allow increased insight to investigate the river response to a complex sequence of regulatory events such as development of bars, islands and riparian vegetation. Until the mid-19th century the river had a multi-thread channel pattern. Thereafter (1852) the river was straightened and diverted. Upstream of Mezzolombardo village the river was constrained between embankments of approximately 100 m width while downstream they are of approximately 50 m width. Since channelization some interesting geomorphic changes have appeared in the river e.g. the appearance of alternate bars in the channel. In 1926 there was a breach in the right bank of the downstream part that resulted in a multi-thread river reach which can be viewed as a recovery to the earlier multi-thread pattern. After the 1950's the flow and sediment supply became strongly regulated by hydropower development. The analysis of aerial images reveals that the multi-thread reach became progressively stabilized by vegetation development over the bars, though signs of some dynamics can still be recognizable today, despite the

  19. River-Based Experiential Learning: the Bear River Fellows Program (United States)

    Rosenberg, D. E.; Shirley, B.; Roark, M. F.


    The Department of Civil and Environmental Engineering, Outdoor Recreation, and Parks and Recreation programs at Utah State University (USU) have partnered to offer a new, unique river-based experiential learning opportunity for undergraduates called the Bear River Fellows Program. The program allows incoming freshmen Fellows to experience a river first hand during a 5-day/4-night river trip on the nearby Bear River two weeks before the start of their first Fall semester. As part of the program, Fellows will navigate the Bear River in canoes, camp along the banks, interact with local water and environmental managers, collect channel cross section, stream flow, vegetation cover, and topological complexity data, meet other incoming freshmen, interact with faculty and graduate students, develop boating and leadership skills, problem solve, and participate as full members of the trip team. Subsequently, Fellows will get paid as undergraduate researchers during their Fall and Spring Freshman semesters to analyze, synthesize, and present the field data they collect. The program is a collaborative effort between two USU academic units and the (non-academic) division of Student Services and supports a larger National Science Foundation funded environmental modelling and management project for the lower Bear River, Utah watershed. We have advertised the program via Facebook and emails to incoming USU freshmen, received 35 applications (60% women), and accepted 5 Fellows into the program (3 female and 2 male). The river trip departs August 14, 2012. The poster will overview the Bear River Fellows Program and present qualitative and preliminary outcomes emerging from the trip and Fellows' work through the Fall semester with the field data they collect. We will also undertake more rigorous and longer longitudinal quantitative evaluation of Program outcomes (for example, in problem-solving and leadership) both in Spring 2013 and in subsequent 2013 and 2014 offerings of the

  20. Irradiation of dehydrated vegetables

    International Nuclear Information System (INIS)

    Esterhuyse, A; Esterhuizen, T.


    The reason for radurization was to decreased the microbial count of dehydrated vegetables. The average absorbed irradiation dose range between 2kGy and 15kGy. The product catagories include a) Green vegetables b) White vegetables c) Powders of a) and b). The microbiological aspects were: Declining curves for the different products of T.P.C., Coliforms, E. Coli, Stap. areus, Yeast + Mold at different doses. The organoleptical aspects were: change in taste, flavour, texture, colour and moisture. The aim is the marketing of irradiated dehydrated vegetables national and international basis

  1. Theory, methods and tools for determining environmental flows for riparian vegetation: Riparian vegetation-flow response guilds (United States)

    Merritt, D.M.; Scott, M.L.; Leroy, Poff N.; Auble, G.T.; Lytle, D.A.


    Riparian vegetation composition, structure and abundance are governed to a large degree by river flow regime and flow-mediated fluvial processes. Streamflow regime exerts selective pressures on riparian vegetation, resulting in adaptations (trait syndromes) to specific flow attributes. Widespread modification of flow regimes by humans has resulted in extensive alteration of riparian vegetation communities. Some of the negative effects of altered flow regimes on vegetation may be reversed by restoring components of the natural flow regime. 2. Models have been developed that quantitatively relate components of the flow regime to attributes of riparian vegetation at the individual, population and community levels. Predictive models range from simple statistical relationships, to more complex stochastic matrix population models and dynamic simulation models. Of the dozens of predictive models reviewed here, most treat one or a few species, have many simplifying assumptions such as stable channel form, and do not specify the time-scale of response. In many cases, these models are very effective in developing alternative streamflow management plans for specific river reaches or segments but are not directly transferable to other rivers or other regions. 3. A primary goal in riparian ecology is to develop general frameworks for prediction of vegetation response to changing environmental conditions. The development of riparian vegetation-flow response guilds offers a framework for transferring information from rivers where flow standards have been developed to maintain desirable vegetation attributes, to rivers with little or no existing information. 4. We propose to organise riparian plants into non-phylogenetic groupings of species with shared traits that are related to components of hydrologic regime: life history, reproductive strategy, morphology, adaptations to fluvial disturbance and adaptations to water availability. Plants from any river or region may be grouped

  2. Levantamento florístico do componente arbustivo-arbóreo da vegetação ciliar na bacia do rio Taperoá, PB, Brasil Floristic survey of components of shrub-tree riparian vegetation in the Taperoá river basin, Paraíba State, Brasil

    Directory of Open Access Journals (Sweden)

    Alecksandra Vieira de Lacerda


    Full Text Available Considerando o papel relevante e o nível de degradação presente nas áreas ciliares, a pesquisa objetivou estudar a composição florística do componente arbustivo-arbóreo da vegetação ciliar em diferentes ambientes hídricos do semi-árido paraibano na bacia do rio Taperoá. O levantamento florístico foi realizado no período de junho/2002 a fevereiro/2003 e abrangeu nove pontos distribuídos ao longo de rios, riachos, lagoa e açude. A definição das atividades apoiou-se em análise de cartas e mapas da vegetação em escala de 1:100.000 e caminhadas aleatórias que permitiram a realização de coleta de material vegetal, utilizado para identificação por meio de consultas a especialistas e de morfologia comparada, usando bibliografia especializada e análise das exsicatas depositadas no herbário Lauro Pires Xavier - JPB (UFPB, João Pessoa, PB. A vegetação arbustivo-arbórea da mata ciliar nos nove pontos amostrados foi representada por 43 espécies, das quais 41 são pertencentes a 19 famílias, e duas espécies permaneceram indeterminadas. As famílias que apresentaram o maior número de espécies foram Mimosaceae (sete, Caesalpiniaceae (cinco e Euphorbiaceae (cinco. Os resultados da análise de agrupamento indicaram que as áreas ciliares apresentaram certa particularização em termos de composição florística, o que se refletiu nos baixos índices de similaridades entre o conjunto de áreas amostradas.Considering the relevant role and the current level of degradation of riparian areas, this work aimed to study the floristic composition of shrub-tree riparian vegetation at different hydric environments in the Taperoá river basin, in the semi-arid region of the Paraíba State, Northeast Brazil. The survey was performed from June 2002 to February 2003. Nine sampling sites were distributed along rivers and streams, and around lagoon, and dam. The definition of activities was based on the analysis of charts and vegetation maps

  3. River nomads

    DEFF Research Database (Denmark)


    sail on the Niger River between Nigeria and Mali. Crossing villages, borders and cultures, they stop only to rest by setting up camp on riverbanks or host villages. In River Nomads, we join the nomadic Kebbawa fishermen on one of their yearly crossing, experiencing their relatively adventurous...

  4. River Piracy

    Indian Academy of Sciences (India)

    There was this highly venerated river Saraswati flowing through. Haryana, Marwar and Bahawalpur in Uttarapath and emptying itself in the Gulf ofKachchh, which has been described in glowing terms by the Rigveda. "Breaking through the mountain barrier", this "swift-flowing tempestuous river surpasses in majesty and.

  5. Balkan Vegetation Database

    NARCIS (Netherlands)

    Vassilev, Kiril; Pedashenko, Hristo; Alexandrova, Alexandra; Tashev, Alexandar; Ganeva, Anna; Gavrilova, Anna; Gradevska, Asya; Assenov, Assen; Vitkova, Antonina; Grigorov, Borislav; Gussev, Chavdar; Filipova, Eva; Aneva, Ina; Knollová, Ilona; Nikolov, Ivaylo; Georgiev, Georgi; Gogushev, Georgi; Tinchev, Georgi; Pachedjieva, Kalina; Koev, Koycho; Lyubenova, Mariyana; Dimitrov, Marius; Apostolova-Stoyanova, Nadezhda; Velev, Nikolay; Zhelev, Petar; Glogov, Plamen; Natcheva, Rayna; Tzonev, Rossen; Boch, Steffen; Hennekens, Stephan M.; Georgiev, Stoyan; Stoyanov, Stoyan; Karakiev, Todor; Kalníková, Veronika; Shivarov, Veselin; Russakova, Veska; Vulchev, Vladimir


    The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019; 019) is a regional database that consists of phytosociological relevés from different vegetation types from six countries on the Balkan Peninsula (Albania, Bosnia and Herzegovina, Bulgaria, Kosovo, Montenegro

  6. Soil and vegetation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.


    Soil sampling and analysis evaluates long-term contamination trends and monitors environmental radionuclide inventories. This section of the 1994 Hanford Site Environmental Report summarizes the soil and vegetation surveillance programs which were conducted during 1994. Vegetation surveillance is conducted offsite to monitor atmospheric deposition of radioactive materials in areas not under cultivation and onsite at locations adjacent to potential sources of radioactivity.

  7. Morphodynamic effects of riparian vegetation growth after stream restoration

    NARCIS (Netherlands)

    Vargas-Luna, Andrés; Crosato, Alessandra; Anders, Niels; Hoitink, Antonius J.F.; Keesstra, Saskia D.; Uijttewaal, Wim S.J.


    The prediction of the morphological evolution of renaturalized streams is important for the success of restoration projects. Riparian vegetation is a key component of the riverine landscape and is therefore essential for the natural rehabilitation of rivers. This complicates the design of

  8. Forest vegetation simulation tools and forest health assessment (United States)

    Richard M. Teck; Melody Steele


    A Stand Hazard Rating System for Central ldaho forests has been incorporated into the Central ldaho Prognosis variant of the Forest Vegetation Simulator to evaluate how insects, disease and fire hazards within the Deadwood River Drainage change over time. A custom interface, BOISE.COMPUTE.PR, has been developed so hazard ratings can be electronically downloaded...

  9. assessment of human impacts on landuse and vegetation cover ...

    African Journals Online (AJOL)


    ADAMAWA STATE, NIGERIA; REMOTE SENSING AND GIS. APPROACH ... image of 1995 were used to study the landuse/vegetation cover changes of the region between 1978 and 1995 – a ... deteriorating environmental quality, loss of important wetlands, ... GIS to the land use of the River Glen catchments in England by ...

  10. The Impact of Human Encroachment and River Bank Agricultural ...

    African Journals Online (AJOL)

    The impact of human encroachment and river bank Agricultural activities on the habitat of the manatee (Trichechus Senegalensis) was investigated. The method of data collection involved the use of a structured questionnaire administered to farmers and fishermen. Vegetation survey in three selected sites along the river ...

  11. Decline of woody vegetation in a saline landscape in the Groundnut Basin, Senegal

    DEFF Research Database (Denmark)

    Sambou, Antoine; Theilade, Ida; Fensholt, Rasmus


    Several studies have documented that vegetation in the Sahel is highly dynamic and is affected by the prevailing climatic conditions, as well as by human use of the areas. However, little is known about vegetation dynamics in the large saline areas bordering the rivers of West Africa. Combining s...

  12. Method of producing vegetable puree

    DEFF Research Database (Denmark)


    A process for producing a vegetable puree, comprising the sequential steps of: a)crushing, chopping or slicing the vegetable into pieces of 1 to 30 mm; b) blanching the vegetable pieces at a temperature of 60 to 90°C; c) contacted the blanched vegetable pieces with a macerating enzyme activity; d......) blending the macerated vegetable pieces and obtaining a puree....

  13. Vegetation survey: a new focus for Applied Vegetation Science

    NARCIS (Netherlands)

    Chytry, M.; Schaminee, J.H.J.; Schwabe, A.


    Vegetation survey is an important research agenda in vegetation science. It defines vegetation types and helps understand differences among them, which is essential for both basic ecological research and applications in biodiversity conservation and environmental monitoring. In this editorial, we

  14. Analysis of Vegetation Coverage Change Characteristics in Chongqing Based on MODIS - NDVI Data (United States)

    Jianfeng, WU; Cao, Guangjie; Zhang, Fengtai; Li, Wei; Wang, Haiqing


    In order to study the characteristics of vegetation cover change in Chongqing, MODIS-NDVI is used as data source. In this paper, the change of vegetation coverage in Chongqing from 2000 to 2011 was analyzed by mean value method and difference method from year, spring, summer, autumn and winter respectively. The results showed that the change of vegetation cover was larger than that of the western region on the annual scale. On the seasonal scale, the vegetation in the spring was in the middle with a high and low trend. The higher vegetation area was distributed in the summer area, and the lower area of vegetation was concentrated in the western part of the study area. Vegetation in autumn showed a flaky distribution in space. Winter vegetation to the Yangtze River as the boundary, the south cover is slightly higher than the north.

  15. Incineration of Low Level Radioactive Vegetation for Waste Volume Reduction

    International Nuclear Information System (INIS)

    Malik, N.P.S.; Rucker, G.G.; Looper, M.G.


    The DOE changing mission at Savannah River Site (SRS) are to increase activities for Waste Management and Environmental Restoration. There are a number of Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) locations that are contaminated with radioactivity and support dense vegetation, and are targeted for remediation. Two such locations have been studied for non-time critical removal actions under the National Contingency Plan (NCP). Both of these sites support about 23 plant species. Surveys of the vegetation show that radiation emanates mainly from vines, shrubs, and trees and range from 20,000 to 200,000 d/m beta gamma. Planning for removal and disposal of low-level radioactive vegetation was done with two principal goals: to process contaminated vegetation for optimum volume reduction and waste minimization, and for the protection of human health and environment. Four alternatives were identified as candidates for vegetation removal and disposal: chipping the vegetation and packing in carbon steel boxes (lined with synthetic commercial liners) and disposal at the Solid Waste Disposal Facility at SRS; composting the vegetation; burning the vegetation in the field; and incinerating the vegetation. One alternative 'incineration' was considered viable choice for waste minimization, safe handling, and the protection of the environment and human health. Advantages and disadvantages of all four alternatives considered have been evaluated. For waste minimization and ultimate disposal of radioactive vegetation incineration is the preferred option. Advantages of incineration are that volume reduction is achieved and low-level radioactive waste are stabilized. For incineration and final disposal vegetation will be chipped and packed in card board boxes and discharged to the rotary kiln of the incinerator. The slow rotation and longer resident time in the kiln will ensure complete combustion of the vegetative material

  16. Riparian Vegetation Mapping Along the Hanford Reach

    International Nuclear Information System (INIS)



    to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer

  17. Vegetation survey of PEN Branch wetlands

    Energy Technology Data Exchange (ETDEWEB)


    A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

  18. Nitrogen and phosphorus in the Upper Mississippi River: Transport, processing, and effects on the river ecosystem (United States)

    Houser, J.N.; Richardson, W.B.


    Existing research on nutrients (nitrogen and phosphorus) in the Upper Mississippi River (UMR) can be organized into the following categories: (1) Long-term changes in nutrient concentrations and export, and their causes; (2) Nutrient cycling within the river; (3) Spatial and temporal patterns of river nutrient concentrations; (4) Effects of elevated nutrient concentrations on the river; and (5) Actions to reduce river nutrient concentrations and flux. Nutrient concentration and flux in the Mississippi River have increased substantially over the last century because of changes in land use, climate, hydrology, and river management and engineering. As in other large floodplain rivers, rates of processes that cycle nitrogen and phosphorus in the UMR exhibit pronounced spatial and temporal heterogeneity because of the complex morphology of the river. This spatial variability in nutrient processing creates clear spatial patterns in nutrient concentrations. For example, nitrate concentrations generally are much lower in off-channel areas than in the main channel. The specifics of in-river nutrient cycling and the effects of high rates of nutrient input on UMR have been less studied than the factors affecting nutrient input to the river and transport to the Gulf of Mexico, and important questions concerning nutrient cycling in the UMR remain. Eutrophication and resulting changes in river productivity have only recently been investigated the UMR. These recent studies indicate that the high nutrient concentrations in the river may affect community composition of aquatic vegetation (e. g., the abundance of filamentous algae and duckweeds), dissolved oxygen concentrations in off-channel areas, and the abundance of cyanobacteria. Actions to reduce nutrient input to the river include changes in land-use practices, wetland restoration, and hydrological modifications to the river. Evidence suggests that most of the above methods can contribute to reducing nutrient concentration in

  19. Vegetation Identification With LIDAR

    National Research Council Canada - National Science Library

    Helt, Michael F


    .... The specific terrain element of interest is vegetation, and in particular, tree type. Data taken on April 12th, 2005, were taken over a 10 km 20 km region which is mixed use agriculture and wetlands...

  20. Vegetation and soils (United States)

    Burke, M.K.; King, S.L.; Eisenbies, M.H.; Gartner, D.


    Intro paragraph: Characterization of bottomland hardwood vegetation in relatively undisturbed forests can provide critical information for developing effective wetland creation and restoration techniques and for assessing the impacts of management and development. Classification is a useful technique in characterizing vegetation because it summarizes complex data sets, assists in hypothesis generation about factors influencing community variation, and helps refine models of community structure. Hierarchical classification of communities is particularly useful for showing relationships among samples (Gauche 1982).

  1. Impact of dam-induced hydrological changes on riparian vegetation (United States)

    Tealdi, Stefano; Camporeale, Carlo; Ridolfi, Luca


    Hydrological disturbances are a key factor for the riparian vegetation, which is a highly dynamic ecosystem prone to external forcing. Random fluctuations of water stages drive in fact the alternation of periods of floods and exposure of the vegetated plots. During flooding, the plots are submerged and vegetation is damaged by burial, uprooting and anoxia, while during exposure periods vegetation grows according to the soil moisture content and the phreatic water table depth. The distribution of vegetation along the riparian transect is then directly connected to the stochasticity of river discharges. River damming can have remarkable impacts on the hydrology of a river and, consequently, on the riparian vegetation. Several field studies show how the river regulation induced by artificial reservoirs can greatly modify the statistical moments and the autocorrelation of the discharge time series. The vegetation responds to these changes reducing its overall heterogeneity, declining - substituted by exotic species - and shifting its starting position nearer or far away from the channel center. These latter processes are known as narrowing and widening, respectively. In our work we explore the effects of dam-induced hydrological changes on the narrowing/widening process and on the total biomass along the transect. To this aim we use an eco-hydrological stochastic model developed by Camporeale and Ridolfi [2006], which is able to give a realistic distribution of the biomass along the transect as a function of a few hydrologic, hydraulic and vegetation parameters. We apply the model to an exemplifying case, by investigating the vegetation response to a set of changes in mean discharge and coefficient of variation. The range of these changes is deduced from the analysis of field data in pre- and post-dam conditions. Firstly, we analyze the narrowing/widening process. In particular, we analyze two percentage differences of the starting transversal position with respect to

  2. Towards Biological Restoration of Tehran Megalopolis River Valleys- Case Study: Farahzad River (United States)

    Samadi, Nafishe; Oveis Torabi, Seyed; Akhani, Hossein


    Towards biological restoration of Tehran megalopolis river-valleys: case study Farahzad river 1Nafiseh Samadi, 2OveisTorabi, 3Hossein Akhani 1Mahsab Shargh Company, Tehran ,Iran, 2 Mahsab Shargh Company, Tehran ,Iran, 3Department of Plant Sciences, Halophytes and C4 Research Laboratory, School of Biology, College of Sciences, University of Tehran, PO Box 14155-6455, Tehran, Iran, Tehran is located in northcentral parts of Iran on the alluvium of southern Alborz Mountains. Seven rivers originated from the highlands of N Tehran run inside and around the city. Many of these river valleys have been deformed by a variety of urban utilizations such as garden, building, canal, park, autobahn etc. Tehran with more than eight million populations suffered from adverse environmental conditions such as pollution and scarcity of natural habitats for recreational activities. Ecological restoration of altered river valleys of Tehran is one of the priorities of Tehran municipality started as a pilot project in Farahzad river. Intensive disturbance, conversion into various urban utilization, illegal building construction, waste water release into the river, garbage accumulation, artificial park constructions and domination of invasive species have largely altered the river. Parts of the river located in Pardisan Nature Park was studied before its complete deformation into a modern park. The riparian vegetation consisted of Tamarix ramosissima and Salix acmophylla shrubs with large number of aquatic and palustric plants. The norther parts of the river still contain semi-natural vegetation which change into patchy and intensive degraded habitats towards its southern parts. In northern parts of valley there are old gardens of Morus alba and Juglans regia, and planted trees such as Plataneus oreientalis and Acer negundo. Salix acmophylla, Fraxinus excelsior and Celtis caucasica are native species growing on river margin or

  3. Vegetation mapping of the Mond Protected Area of Bushehr Province (south-west Iran). (United States)

    Mehrabian, Ahmadreza; Naqinezhad, Alireza; Mahiny, Abdolrassoul Salman; Mostafavi, Hossein; Liaghati, Homan; Kouchekzadeh, Mohsen


    Arid regions of the world occupy up to 35% of the earth's surface, the basis of various definitions of climatic conditions, vegetation types or potential for food production. Due to their high ecological value, monitoring of arid regions is necessary and modern vegetation studies can help in the conservation and management of these areas. The use of remote sensing for mapping of desert vegetation is difficult due to mixing of the spectral reflectance of bright desert soils with the weak spectral response of sparse vegetation. We studied the vegetation types in the semiarid to arid region of Mond Protected Area, south-west Iran, based on unsupervised classification of the Spot XS bands and then produced updated maps. Sixteen map units covering 12 vegetation types were recognized in the area based on both field works and satellite mapping. Halocnemum strobilaceum and Suaeda fruticosa vegetation types were the dominant types and Ephedra foliata, Salicornia europaea-Suaeda heterophylla vegetation types were the smallest. Vegetation coverage decreased sharply with the increase in salinity towards the coastal areas of the Persian Gulf. The highest vegetation coverage belonged to the riparian vegetation along the Mond River, which represents the northern boundary of the protected area. The location of vegetation types was studied on the separate soil and habitat diversity maps of the study area, which helped in final refinements of the vegetation map produced.

  4. Assessment of River Habitat Quality in the Hai River Basin, Northern China

    Directory of Open Access Journals (Sweden)

    Yuekui Ding


    Full Text Available We applied a river habitat quality (RHQ assessment method to the Hai River Basin (HRB; an important economic centre in China; to obtain baseline information for water quality improvement; river rehabilitation; and watershed management. The results of the assessment showed that the river habitat in the HRB is seriously degraded. Specifically; 42.41% of the sites; accounting for a river length of 3.31 × 104 km; were designated poor and bad. Habitat in the plain areas is seriously deteriorated; and nearly 50% of the sites; accounting for a river length of 1.65 × 104 km; had either poor or bad habitats. River habitat degradation was attributable to the limited width of the riparian zone (≤5 m; lower coverage of riparian vegetation (≤40%; artificial land use patterns (public and industrial land; frequent occurrence of farming on the river banks and high volumes of solid waste (nearly 10 m3; single flow channels; and rare aquatic plants (≤1 category. At the regional scale; intensive artificial land use types caused by urbanization had a significant impact on the RHQ in the HRB. RHQ was significantly and negatively correlated with farmland (r = 1.000; p < 0.01 and urban land (r = 0.998; p < 0.05; and was significantly and positively correlated with grassland and woodland (r = 1.000; p < 0.01. Intensive artificial land use; created through urbanization processes; has led to a loss of the riparian zone and its native vegetation; and has disrupted the lateral connectivity of the rivers. The degradation of the already essentially black rivers is exacerbated by poor longitudinal connectivity (index of connectivity is 2.08–16.56; caused by reservoirs and sluices. For river habitat rehabilitation to be successful; land use patterns need to be changed and reservoirs and sluices will have to be regulated.

  5. 78 FR 63373 - Cold Treatment for Fresh Fruits and Vegetables; MidAmerica St. Louis Airport, Mascoutah, IL (United States)


    ..., PPQ, APHIS, 4700 River Road Unit 133, Riverdale, MD 20737-1236; (301) 851-2018. SUPPLEMENTARY... treatment) sufficient to kill certain insect pests associated with imported fruits and vegetables and with...

  6. Impacts of vegetation change on groundwater recharge (United States)

    Bond, W. J.; Verburg, K.; Smith, C. J.


    Vegetation change is the accepted cause of increasing river salt concentrations and the salinisation of millions of hectares of farm land in Australia. Replacement of perennial native vegetation by annual crops and pastures following European settlement has altered the water balance causing increased groundwater recharge and mobilising the naturally saline groundwater. The Redesigning Agriculture for Australian Landscapes Program, of which the work described here is a part, was established to develop agricultural practices that are more attuned to the delicate water balance described above. Results of field measurements will be presented that contrast the water balance characteristics of native vegetation with those of conventional agricultural plants, and indicate the functional characteristics required of new agricultural practices to reduce recharge. New agricultural practices may comprise different management of current crops and pastures, or may involve introducing totally new species. In either case, long-term testing is required to examine their impact on recharge over a long enough climate record to encompass the natural variability of rainfall that is characteristic of most Australian farming regions. Field experimentation therefore needs to be complemented and extended by computer simulation. This requires a modelling approach that is more robust than conventional crop modelling because (a) it needs to be sensitive enough to predict small changes in the residual recharge term, (b) it needs to be able to simulate a variety of vegetation in different sequences, (c) it needs to be able to simulate continuously for several decades of input data, and (d) it therefore needs to be able to simulate the period between crops, which often has a critical impact on recharge. The APSIM simulation framework will be used to illustrate these issues and to explore the effect of different vegetation combinations on recharge.

  7. The Vegetables Turned:

    DEFF Research Database (Denmark)

    Carter, Dale


    in the relationship between creative artists and the Anglo-American popular music industry in the mid-1960s. Finally, and in retrospect, the figure of the vegetable cast into relief the counter-culture's utopian and dystopian dynamics as manifested in these song-writers' personal lives, now rendered as contemporary...... lyricist Van Dyke Parks, the incongruous, semantically complex figure of the vegetable came to illuminate aspects of psychedelic consciousness and - part by design, part by accident - the link between LSD and Anglo-American popular music. It threw light, too, on the scope and limits of changes...

  8. Determining Characteristic Vegetation Areas by Terrestrial Laser Scanning for Floodplain Flow Modeling

    Directory of Open Access Journals (Sweden)

    Johanna Jalonen


    Full Text Available Detailed modeling of floodplain flows and associated processes requires data on mixed, heterogeneous vegetation at river reach scale, though the collection of vegetation data is typically limited in resolution or lack spatial information. This study investigates physically-based characterization of mixed floodplain vegetation by means of terrestrial laser scanning (TLS. The work aimed at developing an approach for deriving the characteristic reference areas of herbaceous and foliated woody vegetation, and estimating the vertical distribution of woody vegetation. Detailed experimental data on vegetation properties were gathered both in a floodplain site for herbaceous vegetation, and under laboratory conditions for 2–3 m tall trees. The total plant area (Atot of woody vegetation correlated linearly with the TLS-based voxel count, whereas the Atot of herbaceous vegetation showed a linear correlation with TLS-based vegetation mean height. For woody vegetation, 1 cm voxel size was found suitable for estimating both the Atot and its vertical distribution. A new concept was proposed for deriving Atot for larger areas from the point cloud attributes of small sub-areas. The results indicated that the relationships between the TLS attributes and Atot of the sub-areas can be derived either by mm resolution TLS or by manual vegetation sampling.

  9. Antecedent Rivers

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 8. Antecedent Rivers - Ganga Is Older Than Himalaya. K S Valdiya. General Article Volume 1 Issue 8 August 1996 pp 55-63. Fulltext. Click here to view fulltext PDF. Permanent link: ...


    African Journals Online (AJOL)

    principals randomly selected from one hundred secondary schools in Cross River State. The data collected ... There was no siyriificant influerlce of gender on principals' leadership styles effectiveness. ... result of the cultural stereotyping of males and females by .... schools were single sex boys, another 10 were single sex ...

  11. Trace metal contents of selected seeds and vegetables from oil producing areas of Nigeria. (United States)

    Wegwu, Matthew O; Omeodu, Stephen I


    The concentrations of accumulated trace metals in selected seeds and vegetables collected in the oil producing Rivers State of Nigeria were investigated. The values were compared with those of seeds and vegetables cultivated in Owerri, a less industrialized area in Nigeria. The lead (Pb) and cadmium (Cd) contents of the seeds obtained from Rivers State ranged between 0.10 and 0.23 microg/g dry weight, while those of the seeds cultivated in Owerri fell below the detection limit of 0.01 microg/g dry weight. The highest manganese (Mn) level (902 microg/g dry weight) was found in Irvingia garbonesis seeds cultivated in Rivers State. Similarly, the highest nickel (Ni) value (199 microg/g dry weight) was also obtained in I. garbonesis, however, in the seeds sampled in Owerri. The highest copper (Cu), zinc (Zn), and iron (Fe) levels (16.8, 5.27, and 26.2 microg/g dry weight, resp.) were detected in seeds collected in Rivers State. With the exception of Talinum triangulae, Ocinum gratissimum, and Piper guineese, with Pb levels of 0.09, 0.10, and 0.11 microg/g dry weight, respectively, the Pb and Cd levels in the vegetables grown in Owerri fell below the detection limit of 0.01 microg/g dry weight. The trace metal with the highest levels in all the vegetables studied was Mn, followed by Fe. The highest concentrations of Ni and Cu occurred in vegetables collected from Rivers State, while the highest level of Zn was observed in Piper guineese collected in Owerri, with a value of 21.4 microg/g dry weight. Although the trace metal concentrations of the seeds and vegetables collected in Rivers State tended to be higher than those of the seeds and vegetables grown in Owerri, the average levels of trace metals obtained in this study fell far below the WHO specifications for metals in foods.

  12. leafy vegetable, Gnetum africanum

    African Journals Online (AJOL)

    A prerequisite for successful in vitro culture is the establishment of an aseptic technique, thus the experiment was to investigate suitable sterilization regimes for the leaf explants of Gnetum africanum, an endangered green leafy vegetable. Three sterilization regimes were tested to establish the best regime using three to four ...

  13. Genetic resources of cultivated and volunteer vegetables in Serbia

    Directory of Open Access Journals (Sweden)

    Lazić Branka


    Full Text Available Number of plant species and populations in the diet and agriculture, and knowledge about them, their cultivation and use, represent the biological, cultural and social heritage of the humankind. Due to favourable geographic, soil, and climate conditions, and large diversity of flora in Serbia, there is a rich tradition of vegetable use in the diet, cultivated and volunteer, autochthonous. More than 70 botanical vegetable species that are accepted for long-term preservation are mentioned nowadays in Serbia. Besides that, some plant species that are classified as industrial, medicinal and aromatic plants are being used as vegetables. Vegetables include legumes used as stewing vegetables. Serbia has three vegetable regions: lowlands (along the rivers Danube, Tisa and Sava, Moravian (along three Morava Rivers and their tributaries and mountainous (Eastern, South-eastern and Western areas, Kosovo and Metohija. In these regions, genetic resources of vegetables should be looked for in cultivated and volunteering flora of different domestic and domesticated populations developed due to adaptation to the specific abiotic and biotic factors, including breeders' selection. International and national projects have been organised in the field of preserving genetic resources of vegetables in the past, as well as nowadays in Serbia. Collected samples are stored in Plant Gene Bank of Serbia and in gene banks all over the world. Significant part is located in the collections of national institutes and faculties. Samples are described with passport data, while those in collections even in more detail. However, none of this is sufficient. In the last decades in Serbia, many populations and vegetable species have threatened to disappear. Many villages are disappearing, there are few growers of vegetables, and extinction of numerous valuable genotypes is accelerated by unfavourable weather conditions. Large number of cultivars and vegetable species that were

  14. Canopy Modeling of Aquatic Vegetation: Construction of Submerged Vegetation Index (United States)

    Ma, Z.; Zhou, G.


    The unique spectral characteristics of submerged vegetation in wetlands determine that the conventional terrestrial vegetation index cannot be directly employed to species identification and parameter inversion of submerged vegetation. Based on the Aquatic Vegetation Radiative Transfer model (AVRT), this paper attempts to construct an index suitable for submerged vegetation, the model simulated data and a scene of Sentinel-2A image in Taihu Lake, China are utilized for assessing the performance of the newly constructed indices and the existent vegetation indices. The results show that the angle index composed by 525 nm, 555 nm and 670 nm can resist the effects of water columns and is more sensitive to vegetation parameters such as LAI. Furthermore, it makes a well discrimination between submerged vegetation and water bodies in the satellite data. We hope that the new index will provide a theoretical basis for future research.

  15. Dynamic hydro-climatic networks in pristine and regulated rivers (United States)

    Botter, G.; Basso, S.; Lazzaro, G.; Doulatyari, B.; Biswal, B.; Schirmer, M.; Rinaldo, A.


    Flow patterns observed at-a-station are the dynamical byproduct of a cascade of processes involving different compartments of the hydro-climatic network (e.g., climate, rainfall, soil, vegetation) that regulates the transformation of rainfall into streamflows. In complex branching rivers, flow regimes result from the heterogeneous arrangement around the stream network of multiple hydrologic cascades that simultaneously occur within distinct contributing areas. As such, flow regimes are seen as the integrated output of a complex "network of networks", which can be properly characterized by its degree of temporal variability and spatial heterogeneity. Hydrologic networks that generate river flow regimes are dynamic in nature. In pristine rivers, the time-variance naturally emerges at multiple timescales from climate variability (namely, seasonality and inter-annual fluctuations), implying that the magnitude (and the features) of the water flow between two nodes may be highly variable across different seasons and years. Conversely, the spatial distribution of river flow regimes within pristine rivers involves scale-dependent transport features, as well as regional climatic and soil use gradients, which in small and meso-scale catchments (A guarantee quite uniform flow regimes and high spatial correlations. Human-impacted rivers, instead, constitute hybrid networks where observed spatio-temporal patterns are dominated by anthropogenic shifts, such as landscape alterations and river regulation. In regulated rivers, the magnitude and the features of water flows from node to node may change significantly through time due to damming and withdrawals. However, regulation may impact river regimes in a spatially heterogeneous manner (e.g. in localized river reaches), with a significant decrease of spatial correlations and network connectivity. Provided that the spatial and temporal dynamics of flow regimes in complex rivers may strongly impact important biotic processes

  16. Comparison of Modeling Grassland Degradation with and without Considering Localized Spatial Associations in Vegetation Changing Patterns

    Directory of Open Access Journals (Sweden)

    Yuwei Wang


    Full Text Available Grassland ecosystems worldwide are confronted with degradation. It is of great importance to understand long-term trajectory patterns of grassland vegetation by advanced analytical models. This study proposes a new approach called a binary logistic regression model with neighborhood interactions, or BLR-NIs, which is based on binary logistic regression (BLR, but fully considers the spatio-temporally localized spatial associations or characterization of neighborhood interactions (NIs in the patterns of grassland vegetation. The BLR-NIs model was applied to a modeled vegetation degradation of grasslands in the Xilin river basin, Inner Mongolia, China. Residual trend analysis on the normalized difference vegetation index (RESTREND-NDVI, which excluded the climatic impact on vegetation dynamics, was adopted as a preprocessing step to derive three human-induced trajectory patterns (vegetation degradation, vegetation recovery, and no significant change in vegetation during two consecutive periods, T1 (2000–2008 and T2 (2007–2015. Human activities, including livestock grazing intensity and transportation accessibility measured by road network density, were included as explanatory variables for vegetation degradation, which was defined for locations if vegetation recovery or no significant change in vegetation in T1 and vegetation degradation in T2 were observed. Our work compared the results of BLR-NIs and the traditional BLR model that did not consider NIs. The study showed that: (1 both grazing intensity and road density had a positive correlation to vegetation degradation based on the traditional BLR model; (2 only road density was found to positively correlate to vegetation degradation by the BLR-NIs model; NIs appeared to be critical factors to predict vegetation degradation; and (3 including NIs in the BLR model improved the model performance substantially. The study provided evidence for the importance of including localized spatial

  17. Microbial Contamination of Raw Vegetables in Ahvaz, Iran during 2014-2015

    Directory of Open Access Journals (Sweden)

    Abdol Kazem Neisi


    Full Text Available Background & Aims of the Study: Vegetables are useful for humans as they contain minerals, vitamins, fiber and other nutrients. Eating raw vegetables are a nutritional habit in Iranian families. Raw eating vegetables is the main source of parasitic infections. The aim of this study was to determine microbial contamination of raw vegetables in Ahvaz, Iran during 2014-2015. Materials and Methods: In this study, 20 samples collected from markets of Ahvaz. Average weight of collecting raw vegetables was 1 to 2 kilograms. Then, raw vegetables were washed by 4 to 5 liter tap water. For parasitic ova washed water leaved for 24 hours for sedimentation and then the supernatant poured and about 50 to 100 milliliter of settled water transferred to 15 ml centrifugal tubes. After centrifugation, pellet floated and finally parasitic ova were observed microscopically (corrected Bailenger method. The multiple tube method used for Coliform bacteria (Total & Faecal examination. Results: Maximum Coliform bacteria was in Kootabdullah samples (total Coliform was 25893319.52 MPN/100ml and Fecal Coliform was 15054572.83 MPN/100ml. Maximum Ascaris ova in Hamidieh was 43.3 per liter and Sheiban 36.66 per litter. Conclusion: Microbial contamination of raw vegetables, especially in Kootabdullah, possibly was due to Karoon river water pollution by sewage discharge of Ahvaz city, and also in Hamidieh possibly due to Karkheh river water pollution by sewage discharge of Hamidieh city. Thus, sewage treatment of these cities before discharging in rivers is necessary.

  18. Review of Vegetable Market Development in China

    Institute of Scientific and Technical Information of China (English)

    Chaoping; LUO; Yuandong; NI; Qiong; ZHAI


    This paper has reviewed vegetable market development from vegetable circulation system, the develop history of the liberalize vegetable market and the growth of the vegetable wholesale market in China. From the development of vegetables market in China and its characteristics: the development of vegetable market in China is related to vegetable market system, the change of institution, some technology development and infrastructure. this paper has put forward some related measures to perfect the vegetable market and improve the vegetable circulation efficiency in China.

  19. Cruciferous Vegetables and Cancer Prevention (United States)

    ... case-control studies have found that people who ate greater amounts of cruciferous vegetables had a lower ... Professionals’ Follow-up Study—showed that women who ate more than 5 servings of cruciferous vegetables per ...

  20. Antecedent Rivers

    Indian Academy of Sciences (India)

    far north of the high NandaDevi (7,817 m) - Api Nampa. (7,132 m) range of the Himadri. The Sindhu flows northwestwards, the Satluj goes west, the Karnali takes the southerly course and the Tsangpo flows east. These rivers flow through their pristine channels, carved out at the very outset about 50 to 55 m.y (million years) ...

  1. Preface to the volume Large Rivers (United States)

    Latrubesse, Edgardo M.; Abad, Jorge D.


    The study and knowledge of the geomorphology of large rivers increased significantly during the last years and the factors that triggered these advances are multiple. On one hand, modern technologies became more accessible and their disseminated usage allowed the collection of data from large rivers as never seen before. The generalized use of high tech data collection with geophysics equipment such as acoustic Doppler current profilers-ADCPs, multibeam echosounders, plus the availability of geospatial and computational tools for morphodynamics, hydrological and hydrosedimentological modeling, have accelerated the scientific production on the geomorphology of large rivers at a global scale. Despite the advances, there is yet a lot of work ahead. Good parts of the large rivers are in the tropics and many are still unexplored. The tropics also hold crucial fluvial basins that concentrate good part of the gross domestic product of large countries like the Parana River in Argentina and Brazil, the Ganges-Brahmaputra in India, the Indus River in Pakistan, and the Mekong River in several countries of South East Asia. The environmental importance of tropical rivers is also outstanding. They hold the highest biodiversity of fluvial fauna and alluvial vegetation and many of them, particularly those in Southeast Asia, are among the most hazardous systems for floods in the entire world. Tropical rivers draining mountain chains such as the Himalaya, the Andes and insular Southeast Asia are also among the most heavily sediment loaded rivers and play a key role in both the storage of sediment at continental scale and the transference of sediments from the continent to the Ocean at planetary scale (Andermann et al., 2012; Latrubesse and Restrepo, 2014; Milliman and Syvitski, 1992; Milliman and Farsnworth, 2011; Sinha and Friend, 1994).

  2. Vegetative Analysis of the Flookplain of the Trinity River, Texas, (United States)


    humilis var. longiflora (Gray) Fern. Ruellia Ruellia nudiflora (Gray)1*~ n_ __ Rush Juncus nodatus Coy.f Rush Juncus Torreyi Coy. Rush-foil...scurfpea Psoralea rhombifolia T. & G.J Royal fern Osmunda reai var. §pectabilis (Willd.) Gray Ruellia Ruellia caroliniensis (Walt.) Steud. Ruellia Ruellia ...o’clock Mirabilis nyctaginea (Michx.) 1 Wild indigo Baptisia Nuttalliana, SmallJ Wild onion Allium canadense L. Wild petunia Ruellia Corzoi Tharp & Barkl

  3. Vegetation survey of Four Mile Creek wetlands. [Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Loehle, C.


    A survey of forested wetlands along upper Four Mile Creek was conducted. The region from Road 3 to the creek headwaters was sampled to evaluate the composition of woody and herbaceons plant communities. All sites were found to fall into either the Nyssa sylvatica (Black Gum) -- Persea borbonia (Red Bay) or Nyssa sylvatica -- Acer rubrum (Red Maple) types. These community types are generally species-rich and diverse. Previous studies (Greenwood et al., 1990; Mackey, 1988) demonstrated contaminant stress in areas downslope from the F- and H-Area seepage basins. In the present study there were some indications of contaminant stress. In the wetland near H-Area, shrub basal area, ground cover stratum species richness, and diversity were low. In the area surrounding the F-Area tree kill zone, ground cover stratum cover and shrub basal area were low and ground cover stratum species richness was low. The moderately stressed site at F-Area also showed reduced overstory richness and diversity and reduced ground cover stratum richness. These results could, however, be due to the very high basal area of overstory trees in both stressed F-Area sites that would reduce light availability to understory plants. No threatened or endangered plant species were found in the areas sampled. 40 refs., 4 figs., 8 tabs.

  4. Adaptive restoration of river terrace vegetation through iterative experiments (United States)

    Dela Cruz, Michelle P.; Beauchamp, Vanessa B.; Shafroth, Patrick B.; Decker, Cheryl E.; O’Neil, Aviva


    Restoration projects can involve a high degree of uncertainty and risk, which can ultimately result in failure. An adaptive restoration approach can reduce uncertainty through controlled, replicated experiments designed to test specific hypotheses and alternative management approaches. Key components of adaptive restoration include willingness of project managers to accept the risk inherent in experimentation, interest of researchers, availability of funding for experimentation and monitoring, and ability to restore sites as iterative experiments where results from early efforts can inform the design of later phases. This paper highlights an ongoing adaptive restoration project at Zion National Park (ZNP), aimed at reducing the cover of exotic annual Bromus on riparian terraces, and revegetating these areas with native plant species. Rather than using a trial-and-error approach, ZNP staff partnered with academic, government, and private-sector collaborators to conduct small-scale experiments to explicitly address uncertainties concerning biomass removal of annual bromes, herbicide application rates and timing, and effective seeding methods for native species. Adaptive restoration has succeeded at ZNP because managers accept the risk inherent in experimentation and ZNP personnel are committed to continue these projects over a several-year period. Techniques that result in exotic annual Bromus removal and restoration of native plant species at ZNP can be used as a starting point for adaptive restoration projects elsewhere in the region.

  5. Riparian Vegetation Mapping Along the Hanford Reach

    Energy Technology Data Exchange (ETDEWEB)



    2002 to support development of a complete data layer describing riparian vegetation cover types on the Columbia River adjacent to the Hanford Site boundaries. Included with this report are the preliminary riparian vegetation maps and the associated metadata for that GIS layer.

  6. Do riparian plant community characteristics differ between Tamarix (L.) invaded and non-invaded sites on the upper Verde River, Arizona? (United States)

    Tyler D. Johnson; Thomas E. Kolb; Alvin L. Medina


    Invasion by Tamarix (L.) can severely alter riparian areas of the western U.S., which are globally rare ecosystems. The upper Verde River, Arizona, is a relatively free-flowing river and has abundant native riparian vegetation. Tamarix is present on the upper Verde but is a minor component of the vegetation (8% of stems). This...

  7. Dynamic Assessment on the Landscape Patterns and Spatio-temporal Change in the mainstream of Tarim River (United States)

    Zhang, Hui; Xue, Lianqing; Yang, Changbing; Chen, Xinfang; Zhang, Luochen; Wei, Guanghui


    The Tarim River (TR), as the longest inland river at an arid area in China, is a typical regions of vegetation variation research and plays a crucial role in the sustainable development of regional ecological environment. In this paper, the newest dataset of MODND1M NDVI, at a resolution of 500m, were applied to calculate vegetation index in growing season during the period 2000-2015. Using a vegetation coverage index, a trend line analysis, and the local spatial autocorrelation analysis, this paper investigated the landscape patterns and spatio-temporal variation of vegetation coverage at regional and pixel scales over mainstream of the Tarim River, Xinjiang. The results showed that (1) The bare land area on both sides of Tarim River appeared to have a fluctuated downward trend and there were two obvious valley values in 2005 and 2012. (2) Spatially, the vegetation coverage improved areas is mostly distributed in upstream and the degraded areas is mainly distributed in the left bank of midstream and the end of Tarim River during 2000-2005. (3) The local spatial auto-correlation analysis revealed that vegetation coverage was spatially positive autocorrelated and spatial concentrated. The high-high self-related areas are mainly distributed in upstream, where vegetation cover are relatively good, and the low-low self-related areas are mostly with lower vegetation cover in the lower reaches of Tarim River.

  8. Assessing Riparian Vegetation Condition and Function in Disturbed Sites of the Arid Northwestern Mexico

    Directory of Open Access Journals (Sweden)

    Lara Cornejo-Denman


    Full Text Available Transformation or modification of vegetation distribution and structure in arid riparian ecosystems can lead to the loss of ecological function. Mexico has 101,500,000 ha of arid lands, however there is a general lack of information regarding how arid riparian ecosystems are being modified. To assess these modifications, we use eight sites in the San Miguel River (central Sonora to analyze (1 riparian vegetation composition, structure and distribution using field sampling and remote sensing data from Unmanned Aerial Vehicles (UAV; (2 productivity (proxies, using vegetation indices derived from satellite data; and (3 variability posed by riparian vegetation and vegetation adjacent to riparian habitats. The development of a simple yet informative Anthropogenic-disturbance Index (ADI allowed us to classify and describe each study site. We found sharp differences in vegetation composition and structure between sites due to the absence/presence of obligate-riparian species. We also report significant difference between EVI (Enhanced Vegetation Index values for the dry season among vegetation types that develop near the edges of the river but differ in composition, suggesting that land cover changes form obligate-riparian to facultative-riparian species can lead to a loss in potential productivity. Finally, our tests suggest that sites with higher disturbance present lower photosynthetic activity.

  9. River Corridor Easements (United States)

    Vermont Center for Geographic Information — A River Corridor Easement (RCE) is an area of conserved land adjacent to a river or stream that was conserved to permanently protect the lateral area the river needs...

  10. Assessment of Pen Branch delta and corridor vegetation changes using multispectral scanner data 1992--1994

    International Nuclear Information System (INIS)


    Airborne multispectral scanner data were used to monitor natural succession of wetland vegetation species over a three-year period from 1992 through 1994 for Pen Branch on the Savannah River Site in South Carolina. Image processing techniques were used to identify and measure wetland vegetation communities in the lower portion of the Pen Branch corridor and delta. The study provided a reliable means for monitoring medium- and large-scale changes in a diverse environment. Findings from the study will be used to support decisions regarding remediation efforts following the cessation of cooling water discharge from K reactor at the Department of Energy's Savannah River Site in South Carolina

  11. River Diversions and Shoaling

    National Research Council Canada - National Science Library

    Letter, Jr., Joseph V; Pinkard, Jr., C. F; Raphelt, Nolan K


    This Coastal and Hydraulics Engineering Technical Note describes the current knowledge of the potential impacts of river diversions on channel morphology, especially induced sedimentation in the river channel...

  12. Phenolation of vegetable oils

    Directory of Open Access Journals (Sweden)



    Full Text Available Novel bio-based compounds containing phenols suitable for the syn­thesis of polyurethanes were prepared. The direct alkylation of phenols with different vegetable oils in the presence of superacids (HBF4, triflic acid as ca­talysts was studied. The reaction kinetics was followed by monitoring the de­crease of the double bond content (iodine value with time. In order to under­stand the mechanism of the reaction, phenol was alkylated with model com­pounds. The model compounds containing one internal double bond were 9-oc­tadecene and methyl oleate and those with three double bonds were triolein and high oleic safflower oil (82 % oleic acid. It was shown that the best structures for phenol alkylation are fatty acids with only one double bond (oleic acid. Fatty acids with two double bonds (linoleic acid and three double bonds (lino­lenic acid lead to polymerized oils by a Diels–Alder reaction, and to a lesser extent to phenol alkylated products. The reaction product of direct alkylation of phenol with vegetable oils is a complex mixture of phenol alkylated with poly­merized oil (30–60 %, phenyl esters formed by transesterification of phenol with triglyceride ester bonds (<10 % and unreacted oil (30 %. The phenolated vegetable oils are new aromatic–aliphatic bio-based raw materials suitable for the preparation of polyols (by propoxylation, ethoxylation, Mannich reactions for the preparation of polyurethanes, as intermediates for phenolic resins or as bio-based antioxidants.

  13. Mechanisms of vegetation uprooting by flow in alluvial non-cohesive sediment

    Directory of Open Access Journals (Sweden)

    K. Edmaier


    Full Text Available The establishment of riparian pioneer vegetation is of crucial importance within river restoration projects. After germination or vegetative reproduction on river bars juvenile plants are often exposed to mortality by uprooting caused by floods. At later stages of root development vegetation uprooting by flow is seen to occur as a consequence of a marked erosion gradually exposing the root system and accordingly reducing the mechanical anchoring. How time scales of flow-induced uprooting do depend on vegetation stages growing in alluvial non-cohesive sediment is currently an open question that we conceptually address in this work. After reviewing vegetation root issues in relation to morphodynamic processes, we then propose two modelling mechanisms (Type I and Type II, respectively concerning the uprooting time scales of early germinated and of mature vegetation. Type I is a purely flow-induced drag mechanism, which causes alone a nearly instantaneous uprooting when exceeding root resistance. Type II arises as a combination of substantial sediment erosion exposing the root system and resulting in a decreased anchoring resistance, eventually degenerating into a Type I mechanism. We support our conceptual models with some preliminary experimental data and discuss the importance of better understanding such mechanisms in order to formulate sounding mathematical models that are suitable to plan and to manage river restoration projects.

  14. Collection and analysis of remotely sensed data from the Rhode River Estuary Watershed (United States)

    Jenkins, D. W.; Williamson, F. S. L.


    The remote sensing study to survey the Rhode River watershed for spray irrigation with secondarily treated sewage is reported. The standardization of Autumn coloration changes with Munsell color chips is described along with the mapping of old field vegetation for the spray irrigation project. The interpretation and verification of salt marsh vegetation by remote sensing of the water shed is discussed.

  15. Analysis of relationships between land surface temperature and land use changes in the Yellow River Delta (United States)

    Ning, Jicai; Gao, Zhiqiang; Meng, Ran; Xu, Fuxiang; Gao, Meng


    This study analyzed land use and land cover changes and their impact on land surface temperature using Landsat 5 Thematic Mapper and Landsat 8 Operational Land Imager and Thermal Infrared Sensor imagery of the Yellow River Delta. Six Landsat images comprising two time series were used to calculate the land surface temperature and correlated vegetation indices. The Yellow River Delta area has expanded substantially because of the deposited sediment carried from upstream reaches of the river. Between 1986 and 2015, approximately 35% of the land use area of the Yellow River Delta has been transformed into salterns and aquaculture ponds. Overall, land use conversion has occurred primarily from poorly utilized land into highly utilized land. To analyze the variation of land surface temperature, a mono-window algorithm was applied to retrieve the regional land surface temperature. The results showed bilinear correlation between land surface temperature and the vegetation indices (i.e., Normalized Difference Vegetation Index, Adjusted-Normalized Vegetation Index, Soil-Adjusted Vegetation Index, and Modified Soil-Adjusted Vegetation Index). Generally, values of the vegetation indices greater than the inflection point mean the land surface temperature and the vegetation indices are correlated negatively, and vice versa. Land surface temperature in coastal areas is affected considerably by local seawater temperature and weather conditions.

  16. Environmental gradients across wetland vegetation groups in the arid slopes of Western Alborz Mountains, N. Iran

    Directory of Open Access Journals (Sweden)

    Asghar Kamrani


    Full Text Available Mountain wetlands are unique ecosystems in the arid southern slopes of Alborz range, the second largest range in Iran. The spatial distribution characteristics of wetland vegetation in the arid region of the Alborz and the main factors affecting their distributional patterns were studied. A classification of vegetation and ecological characteristics were carried out using data extracted from 430 relevés in 90 wetland sites. The data were analyzed using Two Way Indicator Species Analysis (TWINSPAN and detrended correspondence analysis (DCA. The wetland vegetation of Alborz Mountain was classified into four large groups. The first vegetation group was calcareous rich vegetation, mainly distributed in the river banks and characterized by helophytes such as Bolboschoenus affinis as indicator species. The second group was saline transitional vegetation, distributed in the ecotone areas and dominated by Phragmites australis. The third vegetation group is wet meadow vegetation which mainly consists of geophytes, endemic and Irano-Turanian species, distributed in the higher altitudes. This vegetation is mainly characterized by indicator species such as Carex orbicularis, high level concentration of Fe2+ and percentage of organic matter in the soil. The fourth vegetation group is aquatic vegetation, distributed in the lakeshores. The aquatic group species are mainly hydrophytic such as Batrachium trichophyllum. The TWINSPAN vegetation groups could be also recognized in the DCA graphs and ecologically differentiated by ANOVA of studied variables. Four vegetation groups can be differentiated on two first axes of indirect ordination. There is a gradient of pH, EC and organic matter associated with altitude on the DCA diagram. Correlation analysis between the axes of DCA and environmental factors shows that altitude, soil texture and other dependant environmental variables (e.g. pH are the main environmental factors affecting the distribution of wetland

  17. Speciation of cadmium, copper, lead and zinc in the waters of River ...

    African Journals Online (AJOL)

    The water of river Mzimbazi and its attributaries are known to contain heavy metals originating from industry and the water is used for domestic and vegetable irrigation purposes. The present study describes chemical forms of some of the heavy metals found in the water. Water samples from different locations along river ...

  18. Saltcedar control and water salvage on the Pecos River, Texas, 1999 to 2003 (United States)

    Charles R. Hart; Larry D. White; Alyson McDonald; Zhuping Sheng


    A large scale ecosystem restoration program was initiated in 1997 on the Pecos River in western Texas. Saltcedar (Tamarix spp.), a non-native invasive tree, had created a near monoculture along the banks of the river by replacing most native vegetation. Local irrigation districts, private landowners, federal and state agencies, and private industry...

  19. The lower San Pedro River: hydrology and flow restoration for biodiversity conservation (United States)

    Jeanmarie Haney


    The lower San Pedro River, downstream from Benson, is a nearly unfragmented habitat containing perennial flow reaches that support riparian vegetation that serve as “stepping stones” for migratory species. The Nature Conservancy has purchased farm properties and retired agricultural pumping along the lower river, based largely on results from hydrologic analyses...

  20. Response of Vegetation on Gravel Bars to Management Measures and Floods: Case Study From the Czech Republic

    Directory of Open Access Journals (Sweden)

    Eremiášová Renata


    Full Text Available This article investigates response of vegetation on gravel bars to management measures and floods. The management measures consisted of the partial removal of gravel and vegetation cover, and were applied to six gravel bars on the Ostravice River, Czech Republic. Unexpected floods occu-rred in 2010, with the amplitude of 5- to 50-year repetition. Research of vegetation on the gravel bars consisted of vegetation survey before the management works; the monitoring of vegetation development over the following year and the verification of the relationships of species diversity, successional stages and the biotope conditions with the help of multivariate analysis (detrended correspondence analysis. Vegetation on the gravel bars was at different successional stages, and had higher diversity and vegetation cover before the management measures and floods. The mul-tivariate analysis revealed a shift toward initial successional stages with high demand on moisture, temperature and light after both management measures and floods.

  1. Multiscale influence of woody riparian vegetation on fluvial topography quantified with ground-based and airborne lidar (United States)

    Bywater-Reyes, Sharon; Wilcox, Andrew C.; Diehl, Rebecca M.


    Coupling between riparian vegetation and river processes can result in the coevolution of plant communities and channel morphology. Quantifying biotic-abiotic interactions remains difficult because of the challenges in making and analyzing appropriately scaled observations. We measure the influence of woody vegetation on channel topography at the patch and reach scales in a sand bed, dryland river system (Santa Maria River, Arizona) with native Populus and invasive Tamarix. At the patch scale, we use ground-based lidar to relate plant morphology to "tail bars" formed in the lee of vegetation. We find vegetation roughness density (λf) to most influence tail-bar shape and size, suggesting coherent flow structures associated with roughness density are responsible for sediment deposition at this scale. Using airborne lidar, we test whether relationships between topography and vegetation morphology observed at the patch scale are persistent at the reach scale. We find that elevation of the channel (relative to the local mean) covaries with a metric of vegetation density, indicating analogous influences of vegetation density on topography across spatial scales. While these results are expected, our approach provides insight regarding interactions between woody riparian vegetation and channel topography at multiple scales, and a means to quantify such interactions for use in other field settings.

  2. Orbital scale vegetation change in Africa (United States)

    Dupont, Lydie


    Palynological records of Middle and Late Pleistocene marine sediments off African shores is reviewed in order to reveal long-term patterns of vegetation change during climate cycles. Whether the transport of pollen and spores from the source areas on the continent to the ocean floor is mainly by wind or predominantly by rivers depends on the region. Despite the differences in transportation, accumulation rates in the marine sediments decline exponentially with distance to the shore. The marine sediments provide well-dated records presenting the vegetation history of the main biomes of western and southern Africa. The extent of different biomes varied with the climate changes of the glacial interglacial cycle. The Mediterranean forest area expanded during interglacials, the northern Saharan desert during glacials, and the semi-desert area in between during the transitions. In the sub-Saharan mountains ericaceous scrubland spread mainly during glacials and the mountainous forest area often increased during intermediate periods. Savannahs extended or shifted to lower latitudes during glacials. While the representation of the tropical rain forest fluctuated with summer insolation and precession, that of the subtropical biomes showed more obliquity variability or followed the pattern of glacial and interglacials.

  3. Impacts of the Anomalous Mississippi River Discharge and Diversions on Phytoplankton Blooming in the Northeastern Gulf of Mexico in August 2010 (United States)

    O'Connor, Brendan Sean

    On April 20, 2010 a tragic explosion aboard the Deepwater Horizon (DWH) drilling rig marked the beginning of one of the worst environmental disasters in history. For 87 days oil and gas were released into the Gulf of Mexico. In August 2010, anomalous phytoplankton activity was identified in the Northeastern Gulf of Mexico, using the Fluorescence Line Height (FLH) ocean color product. The FLH anomaly was bound by approximately 30--28° North and 90--86° West and there was a suggestion that this anomaly may have occurred due to the presence of oil. This study was designed to examine alternative explanations and to determine what influence the Mississippi River and the freshwater diversions, employed in the response efforts, may have had on the development of the FLH anomaly. The combination of the anomalously high flow rate in the Mississippi River observed in June-August 2010, the use of freshwater diversions, and three severe storms increased the flow of water through the adjoining marshes. We propose that these conditions reduced the residence time of water and nutrients on the wetlands, and likely mobilized nutrients leading to increased fresh water and nutrients being discharge to the coasts around the Mississippi Delta. Salinity contour maps created from data collected by ships operating in the Northeastern Gulf of Mexico showed that the 31 isohaline was upwards of 250km east of the Mississippi River Birds Foot Delta in August 2010. The American Seas (AmSeas) numerical circulation model was used to examine the dispersal and distribution of water parcels from the Mississippi River and freshwater diversions. Two virtual particle seeding locations were used to trace particles to obtain a measure of the percentage of particles entering a Region of Interest (ROI) located in the center of the FLH anomaly, i.e. 150 km east of the Mississippi Delta. All environmental data examined suggest that the eastward dispersal of the Mississippi River water including that

  4. Vegetation dynamics of the Tanbi Wetland National Park, The Gambia (United States)

    Ceesay, A.


    Changes in mangrove vegetation have been identified as an important indicator of environmental change. The mangroves of the Tanbi Wetland National Park (TWNP) connect the Atlantic coast with the estuary of the River Gambia and as such, play an invaluable role in the agriculture, tourism and fisheries sectors of The Gambia. Our research seeks to understand the long-term changes in the mangrove vegetation to strengthen the formulation of sustainable alternative livelihoods and adaptation strategies to climate change. Mangrove vegetation dynamics was assessed by remote sensing, using decadal Landsat images covering 1973 - 2012. Physicochemical parameters were analyzed during the rainy and dry seasons of The Gambia for correlation with climate data. Our findings indicate that the long-term changes in salinity (24.5 and 35.8ppt) and water temperature (27.6oC and 30.2oC) during the rainy and dry seasons respectively are retarding mangrove growth. Mangrove vegetation cover declined by 6%, while grassland increased by 56.4%. This research concludes that long-term hyper-salinity is the cause for the stunted vegetation and lack of mangrove rejuvenation. We propose that specialized replanting systems such as the use of saplings be adopted instead of the conventional use of propagules. Alternative livelihoods also need to be diversified to support coastal communities.

  5. Effects of metals on vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Press, N P


    Prospectors have long known that abnormal concentrations of metals in the soil overlying an ore deposit can affect the vegetation rooting in this soil; mineral deposits have even been discovered because of such vegetation changes. Recently, many people have become interested in the possibility of remote sensing such vegetation changes, and perhaps using the results in conjunction with airborne geophysics and photogeological interpretation in integrated prospecting programs.

  6. Vegetation and acidification, Chapter 5 (United States)

    David R. DeWalle; James N. Kochenderfer; Mary Beth Adams; Gary W. Miller


    In this chapter, the impact of watershed acidification treatments on WS3 at the Fernow Experimental Forest (FEF) and at WS9 on vegetation is presented and summarized in a comprehensive way for the first time. WS7 is used as a vegetative reference basin for WS3, while untreated plots within WS9 are used as a vegetative reference for WS9. Bioindicators of acidification...

  7. Relishes: The new pickled vegetables

    Directory of Open Access Journals (Sweden)

    Tepić Aleksandra N.


    Full Text Available There have been an increasing interest of consumers for a ide variety of pickled vegetable products worldwide. Regarding the regional vegetable supplies and relatively poor assortment of ready-to-use products, the need to broaden the offer of domestic pickled vegetables at the market came out. In this work recipes for different vegetables, spices and condiments were developed. The best graded samples were analyzed for their main chemical composition (dry matter, proteins, oils and fats, total acidity, total sugars, sucrose, starch, cellulose, pH and energy- values.

  8. Crestridge Vegetation Map [ds211 (United States)

    California Natural Resource Agency — This layer represents vegetation communities in the Department of Fish and Game's Crestridge Ecological Reserve. The County of San Diego, the Conservation Biology...

  9. Encouraging children to eat vegetables


    Buh, Alenka


    It is important for children to maintain a healthy and balanced diet throughout their childhood and youth. Children tend to skip vegetables in their meals as they are not much liked; the tastes of vegetables are also highly specific and each individual has to get used to them by repeated tasting. The aim of this undergraduate thesis was to analyse how often children eat vegetables, which types of vegetables they like and which they do not, to determine if the executed method of pedagogica...

  10. A vegetal Geiger counter

    International Nuclear Information System (INIS)



    In order to study the Chernobyl accident impact on ecosystems, Ukrainian and Swiss scientists have used a plant: the Arabidopsis thaliana. They have introduced in its genome a gene coding an enzyme called β-glucuronidase. This substance, when it is expressed, colours vegetal cells blue. In fact the introduced gene is divided between 2 paired chromosomes. When the plant is placed on a nuclear contaminated soil, radiation damaged chromosomes exchange fragments and the 2 parts of the enzyme gene may recombine, the enzyme can then be expressed. For low and medium contamination ( 2 ) biologists have found a correlation between the number of blue spots on the plant and the irradiation rate. (A.C.)

  11. Genetic improvement of vegetables

    International Nuclear Information System (INIS)

    Jaramillo Vasquez, J.G.


    Some genetic bases of the improvement of vegetables are given. The objectives of the genetic improvement and the fundamental stages of this process are done. The sources of genetic variation are indicated and they are related the reproduction systems of the main horticultural species. It is analyzed the concept of genetic inheritance like base to determine the procedures more appropriate of improvement. The approaches are discussed, has more than enough phenotypic value, genetic action and genotypic variance; Equally the heredability concepts and value of improvement. The conventional methods of improvement are described, like they are: the introduction of species or varieties, the selection, the pure line, the pedigree method, the selection for families, the recurrent selection, the selection for unique seed, the haploids method, the selection for heterosis and the synthetic varieties

  12. Fruits and vegetables dehydration

    International Nuclear Information System (INIS)

    De Ita, A; Flores, G; Franco, F


    Dehydration diagrams were determined by means of Differential Thermal Analysis, DTA, and Thermo Gravimetric Analysis, TGA, curves of several simultaneous fruits and vegetables, all under the same conditions. The greater mass loss is associated with water containing in the structure of the investigated materials at low temperature. In poblano chile water is lost in a single step. The banana shows a very sharply two stages, while jicama can be observed although with a little difficulty three stages. The major mass loss occurs in the poblano chile and the lower in banana. The velocity and temperature of dehydration vary within a small range for most materials investigated, except for banana and cactus how are very different

  13. Fruits and vegetables dehydration (United States)

    de Ita, A.; Flores, G.; Franco, F.


    Dehydration diagrams were determined by means of Differential Thermal Analysis, DTA, and Thermo Gravimetric Analysis, TGA, curves of several simultaneous fruits and vegetables, all under the same conditions. The greater mass loss is associated with water containing in the structure of the investigated materials at low temperature. In poblano chile water is lost in a single step. The banana shows a very sharply two stages, while jicama can be observed although with a little difficulty three stages. The major mass loss occurs in the poblano chile and the lower in banana. The velocity and temperature of dehydration vary within a small range for most materials investigated, except for banana and cactus how are very different.

  14. Heavy metals in green vegetables and soils from vegetable gardens ...

    African Journals Online (AJOL)

    Edible portions of five varieties of green vegetables, namely amaranth, chinese cabbage, cowpea leaves, leafy cabbage and pumpkin leaves, collected from several areas in Dar es Salaam, were analyzed for lead, cadmium, chromium, zinc, nickel and copper. Except for zinc, the levels of heavy metals in the vegetables ...

  15. Noise-driven cooperative dynamics between vegetation and topography in riparian zones (United States)

    Vesipa, Riccardo; Camporeale, Carlo; Ridolfi, Luca


    Riparian ecosystems exhibit complex biotic and abiotic dynamics, where the triad vegetation-sediments-stream determines the eco-geomorphological 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 fact, in a given plot, vegetation biomass can grow (if the stage is below the plot elevation) or decay (if the stage is above the plot elevation). As a result, biomass exhibits significant temporal variations. In this framework, the capability of vegetation to alter the transect topography (namely, the plot elevation) is crucial. Vegetation can increase the plot elevation by a number of mechanisms (trapping of water- and wind-transported sediment particles, production of organic soil, stabilization of the soil surface). The increment of plot elevation induces the reduction of the plot-specific magnitude, frequency and duration of floods. These more favorable plot-specific hydrological conditions, in turn, induce an increment of biomass. Moreover, the higher the vegetation biomass, the higher the plot elevation increment induced by these mechanisms. In order to elucidate how the stochastically varying water stage and the vegetation-induced topographic alteration shape the bio-morphological characteristics of riparian transects, a stochastic model that takes into account the main links between vegetation, sediments and the stream was adopted. In particular, the capability of vegetation to alter the plot topography was emphasized. In modeling such interactions, the minimalistic approach was pursued. The complex vegetation-sediments-stream interactions were modeled by a set of state-depended stochastic eco-hydraulic equations. The probability density function of vegetation biomass was then analytically evaluated in any transect plot. This pdf strongly depends on the vegetation-topography feedback. We

  16. Vegetable Genetic Resources in China

    Directory of Open Access Journals (Sweden)

    Haiping WANG


    Full Text Available China is recognized as an important region for plant biodiversity based on its vast and historical collection of vegetable germplasm. The aim of this review is to describe the exploration status of vegetable genetic resources in China, including their collection, preservation, evaluation, and utilization. China has established a number of national-level vegetable genetic resources preservation units, including the National Mid-term Genebank for Vegetable Germplasm Resources, the National Germplasm Repository for Vegetatively-Propagated Vegetables, and the National Germplasm Repository for Aquatic Vegetables. In 2015, at least 36 000 accessions were collected and preserved in these units. In the past decade, 44 descriptors and data standards for different species have been published, and most accessions have been evaluated for screening the germplasms for specific important traits such as morphological characteristics, disease resistance, pest resistance, and stress tolerance. Moreover, the genetic diversity and evolution of some vegetable germplasms have been evaluated at the molecular level. Recently, more than 1 000 accessions were distributed to researchers and breeders each year by various means for vegetable research and production. However, additional wild-relative and abroad germplasms from other regions need to be collected and preserved in the units to expand genetic diversity. Furthermore, there is a need to utilize advanced techniques to better understand the background and genetic diversity of a wide range of vegetable genetic resources. This review will provide agricultural scientists’ insights into the genetic diversity in China and provide information on the distribution and potential utilization of these valuable genetic resources. Keywords: vegetable, genetic resource, preservation, evaluation, utilization

  17. Conservation Of Biodiversity In Central Cross River State: The Role ...

    African Journals Online (AJOL)

    The central zone of Cross River State is alarmingly being taken over by secondary vegetation as a result of over cultivation of the land, since the communities there are largely agrarian. There are some forms of traditional religious practices and beliefs typified by shrines, evil forests, sacred water and so on that have direct ...

  18. RiverFlow2D numerical simulation of flood mitigation solutions in the Ebro River

    Directory of Open Access Journals (Sweden)

    I. Echeverribar


    Full Text Available A study of measures oriented to flood mitigation in the mid reach of the Ebro river is presented: elimination of vegetation in the riverbed, use of controlled flooding areas and construction or re-adaptation of levees. The software used is RiverFlow2D which solves the conservative free-surface flow equations with a finite volume method running on GPU. The results are compared with measurements at gauge stations and aerial views. The most effective measure has turned out to be the elimination of vegetation in the riverbed. It is demonstrated that not only the maximum flooded area is narrower but also it reduces the water depth up to 1 m. The other measures have local consequences when the peak discharge is relatively high although they could be useful in case the discharge is lower.

  19. Ecosystem response to removal of exotic riparian shrubs and a transition to upland vegetation (United States)

    Reynolds, Lindsay V.; Cooper, David J.


    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

  20. Vegetation survey of Pen Branch and Four Mile Creek wetlands

    Energy Technology Data Exchange (ETDEWEB)


    One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

  1. Vegetation survey of Pen Branch and Four Mile Creek wetlands

    Energy Technology Data Exchange (ETDEWEB)


    One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

  2. Scales of form roughness on riverbanks with different riparian vegetation (United States)

    Konsoer, K. M.; Rhoads, B. L.; Best, J.; Langendoen, E. J.; Ursic, M.; Abad, J. D.; Garcia, M. H.


    Riverbanks often include topographic irregularities that occur over a range of scales and that are produced by interactions among erosional processes, vegetation, and the geotechnical properties of the banks and floodplains. Irregularity of the bank surface can increase form drag, affecting the overall flow resistance, near-bank shear stresses, and patterns of sediment transport. Understanding how dominant scales of form roughness influence the near-bank flow structure, and thus the shear stress partitioning, is vital for the development of accurate predictive morphodynamic models. In this paper, the scales of bank roughness are examined for two meander bends of a large alluvial river with differing riparian vegetation on the Wabash River near Grayville, Illinois. Detailed measurements of bank topography were obtained using terrestrial LiDAR during low flow events and a multibeam echo sounder (MBES) during bankfull events. These measurements yielded high spatial resolution maps (~5-10 cm) that were used to analyze scales of roughness at different elevations along the banks during both subaerial and subaqueous conditions. The results of these analyses provide insight into the influence of riparian vegetation on form roughness and patterns of near-bank flow structure as documented using acoustic Doppler current profilers (ADCP).

  3. Toxicología Vegetal


    García Fernández, Antonio Juan


    Presentaciones de clase de los temas de Toxicología Vegetal de la licenciatura de Veterinaria de la Universidad de Murcia del curso 2011/12. Presentaciones de Toxicología Vegetal de la asignatura de Toxicología de la Licenciatura de Veterinaria del curso 2011/12

  4. A survey of some insect pests of cultivated vegetables in three ...

    African Journals Online (AJOL)


    ABSTRACT. The survey aimed at identifying insect pests that attack vegetables grown in three irrigation areas along Jakara River in Kano, Nigeria. The areas were Kwarin gogau, Nomansland and. Kwakwaci. Two methods of trapping the insects were employed, namely hand capture for wingless insects as well as hand net ...

  5. Soil amendments promote vegetation establishment and control acidity in coal combustion waste (United States)

    R.M. Danker; D.C. Adriano; Bon-Jun Koo; C.D. Barton


    The effects of adding various soil amendments and a pyrite oxidation inhibitor to aid in the establishment of vegetation and to reduce acid drainage (AD) from coal fly ash and coal reject (FA + CR*) were assessed in an outdoor mesocosm study. Preliminary greenhouse experiments and field observations at the U.S. Department of Energy's Savannah River Site (SRS)...

  6. NDVI indicated characteristics of vegetation cover change in China's metropolises over the last three decades. (United States)

    Sun, Jinyu; Wang, Xuhui; Chen, Anping; Ma, Yuecun; Cui, Mengdi; Piao, Shilong


    How urban vegetation was influenced by three decades of intensive urbanization in China is of great interest but rarely studied. In this paper, we used satellite derived Normalized Difference Vegetation Index (NDVI) and socioeconomic data to evaluate effects of urbanization on vegetation cover in China's 117 metropolises over the last three decades. Our results suggest that current urbanization has caused deterioration of urban vegetation across most cities in China, particularly in East China. At the national scale, average urban area NDVI (NDVI(u)) significantly decreased during the last three decades (P NDVI(u) did not show statistically significant trend before 1990 but decrease remarkably after 1990 (P NDVI(u) turning point. The year when NDVI(u) started to decline significantly for Central China and East China was 1987 and 1990, respectively, while NDVI(u) in West China remained relatively constant until 1998. NDVI(u) changes in the Yangtze River Delta and the Pearl River Delta, two regions which has been undergoing the most rapid urbanization in China, also show different characteristics. The Pearl River Delta experienced a rapid decline in NDVI(u) from the early 1980s to the mid-1990s; while in the Yangtze River Delta, NDVI(u) did not decline significantly until the early 1990s. Such different patterns of NDVI(u) changes are closely linked with policy-oriented difference in urbanization dynamics of these regions, which highlights the importance of implementing a sustainable urban development policy.

  7. Terrestrial Water Storage and Vegetation Resilience to Drought (United States)

    Meyer, V.; Reager, J. T., II; Konings, A. G.


    The expected increased occurrences of hydrologic extreme events such as droughts in the coming decades motivates studies to better understand and predict the response of vegetation to such extreme conditions. Previous studies have addressed vegetation resilience to drought, defined as its ability to recover from a perturbation (Hirota et al., 2011; Vicente-Serrano et al., 2012), but appear to only focus on precipitation and a couple of vegetation indices, hence lacking a key element: terrestrial water storage (TWS). In this study, we combine and compare multiple remotely-sensed hydro-ecological datasets providing information on climatic and hydrological conditions (Tropical Rainfall Measuring Mission (TRMM), Gravity Recovery and Climate Experiment (GRACE)) and indices characterizing the state of the vegetation (vegetation water content using Vegetation Optical Depth (VOD) from SMAP (Soil Moisture Active and Passive), Gross Primary Production (GPP) from FluxCom and Specific Fluorescence Intensity (SFI, from GOSat)) to assess the ability of vegetation to face and recover from droughts across the globe. Our results suggest that GRACE hydrological data bridge the knowledge gap between precipitation deficit and vegetation response. All products are aggregated at a 0.5º spatial resolution and a monthly temporal resolution to match the GRACE Mascon product. Despite these coarse spatiotemporal resolutions, we find that the relationship between existing remotely-sensed eco-hydrologic data varies spatially, both in terms of strength of relationship and time lag, showing the response time of vegetation characteristics to hydrological changes and highlighting the role of water storage. A special attention is given to the Amazon river basin, where two well documented droughts occurred in 2005 and 2010, and where a more recent drought occurred in 2015/2016. References : Hirota, Marina, et al. "Global resilience of tropical forest and savanna to critical transitions." Science

  8. Food production and consumption near the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Hamby, D.M.


    Routine operations at the Savannah River Site (SRS) result in the release of radionuclides to the atmosphere and to the Savannah River. The resulting radiological doses to the off-site maximum individual and the 80-km population are estimated on a yearly basis. These estimates are generated using dose models prescribed in the NRC Reg. Guide 1.109 for the commercial nuclear power industry. A study of land and water usage characteristics in the region of the Savannah River Site has been conducted to determine site-specific values of the NRC dose model parameters. The study`s scope included local characteristics of meat, milk, vegetable production; Savannah River recreational activities and fish harvests; meat, milk, vegetable, and seafood consumption rates; and Savannah River drinking-water populations. Average and maximum consumption rates of beef, milk, vegetables, and fish have been determined for individuals residing in the southern United States. The study suggest that many of the consumption rates provided by the NRC may not be appropriate for residents of the South. Average consumption rates are slightly higher than the defaults provided by the NRC. Maximum consumption rates, however, are typically lower than NRC values. Agricultural productivity in the SRS region was found to be quite different than NRC recommendations. Off-site doses have been predicted using both NRC and SRS parameter values to demonstrate the significance of site-specific data.

  9. Food production and consumption near the Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Hamby, D.M.


    Routine operations at the Savannah River Site (SRS) result in the release of radionuclides to the atmosphere and to the Savannah River. The resulting radiological doses to the off-site maximum individual and the 80-km population are estimated on a yearly basis. These estimates are generated using dose models prescribed in the NRC Reg. Guide 1.109 for the commercial nuclear power industry. A study of land and water usage characteristics in the region of the Savannah River Site has been conducted to determine site-specific values of the NRC dose model parameters. The study's scope included local characteristics of meat, milk, vegetable production; Savannah River recreational activities and fish harvests; meat, milk, vegetable, and seafood consumption rates; and Savannah River drinking-water populations. Average and maximum consumption rates of beef, milk, vegetables, and fish have been determined for individuals residing in the southern United States. The study suggest that many of the consumption rates provided by the NRC may not be appropriate for residents of the South. Average consumption rates are slightly higher than the defaults provided by the NRC. Maximum consumption rates, however, are typically lower than NRC values. Agricultural productivity in the SRS region was found to be quite different than NRC recommendations. Off-site doses have been predicted using both NRC and SRS parameter values to demonstrate the significance of site-specific data.

  10. Historical and current forest landscapes in eastern Oregon and Washington Part II: Linking vegetation characteristics to potential fire behavior and related smoke production. (United States)

    Mark H. Huff; Roger D. Ottmar; Ernesto Alvarado; Robert E. Vihnanek; John F. Lehmkuhl; Paul F. Hessburg; Richard L. Everett


    We compared the potential fire behavior and smoke production of historical and current time periods based on vegetative conditions in forty-nine 5100- to 13 5OO-hectare watersheds in six river basins in eastern Oregon and Washington. Vegetation composition, structure, and patterns were attributed and mapped from aerial photographs taken from 1932 to 1959 (historical)...

  11. Baseline vegetation inventory and productivity assessment for the Syncrude Aurora Mine EIA local study area

    Energy Technology Data Exchange (ETDEWEB)



    This report presented an inventory and assessment of vegetation communities and forest covers within the proposed Aurora Mine local study area. A field inventory was conducted in the summer of 1995 to ground-truth air photo interpretations and to collect data. The inventory includes a classification of vegetation, forest covers and wetlands. It also includes the documentation of uncommon plants and the vegetation productivity estimates of tree, shrub and herbaceous plants. The study area is located east of the Athabasca River about 35 km northeast of Mildred Lake Oil Sands Plant. The area includes portions of Oil Sands Leases 10, 12, 13, 31, and 34 which includes much of the Muskeg River drainage and all of Kearl Lake. 24 refs., 7 tabs., 3 figs.


    Directory of Open Access Journals (Sweden)

    W. K. van Iersel


    Full Text Available River restoration projects, which aim at improved flood safety and increased ecological value, have resulted in more heterogeneous vegetation. However, they also resulted in increasing hydraulic roughness, which leads to higher flood water levels during peak discharges. Due to allowance of vegetation development and succession, both ecological and hydraulic characteristics of the floodplain change more rapidly over time. Monitoring of floodplain vegetation has become essential to document and evaluate the changing floodplain characteristics and associated functioning. Extraction of characteristics of low vegetation using single-epoch remote sensing data, however, remains challenging. The aim of this study was to (1 evaluate the performance of multi-temporal, high-spatial-resolution UAV imagery for extracting temporal vegetation height profiles of grassland and herbaceous vegetation in floodplains and (2 to assess the relation between height development and NDVI changes. Vegetation height was measured six times during one year in 28 field plots within a single floodplain. UAV true-colour and false-colour imagery of the floodplain were recorded coincidently with each field survey. We found that: (1 the vertical accuracy of UAV normalized digital surface models (nDSMs is sufficiently high to obtain temporal height profiles of low vegetation over a growing season, (2 vegetation height can be estimated from the time series of nDSMs, with the highest accuracy found for combined imagery from February and November (RMSE = 29-42 cm, (3 temporal relations between NDVI and observed vegetation height show different hysteresis behaviour for grassland and herbaceous vegetation. These results show the high potential of using UAV imagery for increasing grassland and herbaceous vegetation classification accuracy.

  13. Special study on vegetative covers

    International Nuclear Information System (INIS)


    This report describes the findings of a special study on the use of vegetative covers to stabilize tailings piles for the Uranium Mill Tailings Remedial Action (UMTRA) Project. The principal rationale for using plants would be to establish a dynamic system for controlling water balance. Specifically, vegetation would be used to intercept and transpire precipitation to the atmosphere, rather than allowing water to drain into the tailings and mobilize contaminants. This would facilitate compliance with groundwater standards proposed for the UMTRA Project by the Environmental Protection Agency. The goals of the study were to evaluate the feasibility of using vegetative covers on UMTRA Project piles, define the advantages and disadvantages of vegetative covers, and develop general guidelines for their use when such use seems reasonable. The principal method for the study was to analyze and apply to the UMTRA Project the results of research programs on vegetative covers at other US Department of Energy (DOE) waste management facilities. The study also relied upon observations made of existing stabilized piles at UMTRA Project sites where natural vegetation is growing on the rock-covered surfaces. Water balance and erosion models were also used to quantify the long-term performance of vegetative covers planned for the topslopes of stabilized piles at Grand Junction and Durango, Colorado, two UMTRA Project sites where the decision was made during the course of this special study to use vegetative covers. Elements in the design and construction of the vegetative covers at these two sites are discussed in the report, with explanations of the differing features that reflect differing environmental conditions. 28 refs., 18 figs., 9 tabs

  14. Topographic Signatures of Meandering Rivers with Differences in Outer Bank Cohesion (United States)

    Kelly, S. A.; Belmont, P.


    Within a given valley setting, interactions between river hydraulics, sediment, topography, and vegetation determine attributes of channel morphology, including planform, width and depth, slope, and bed and bank properties. These feedbacks also govern river behavior, including migration and avulsion. Bank cohesion, from the addition of fine sediment and/or vegetation has been recognized in flume experiments as a necessary component to create and maintain a meandering channel planform. Greater bank cohesion slows bank erosion, limiting the rate at which a river can adjust laterally and preventing so-called "runaway widening" to a braided state. Feedbacks of bank cohesion on channel hydraulics and sediment transport may thus produce distinct topographic signatures, or patterns in channel width, depth, and point bar transverse slope. We expect that in bends of greater outer bank cohesion the channel will be narrower, deeper, and bars will have greater transverse slopes. Only recently have we recognized that biotic processes may imprint distinct topographic signatures on the landscape. This study explores topographic signatures of three US rivers: the lower Minnesota River, near Mankato, MN, the Le Sueur River, south central MN, and the Fall River, Rocky Mountain National Park, CO. Each of these rivers has variability in outer bank cohesion, quantified based on geotechnical and vegetation properties, and in-channel topography, which was derived from rtkGPS and acoustic bathymetry surveys. We present methods for incorporating biophysical feedbacks into geomorphic transport laws so that models can better simulate the spatial patterns and variability of topographic signatures.

  15. Interactions among hydrogeomorphology, vegetation, and nutrient biogeochemistry in floodplain ecosystems (United States)

    Noe, G.B.


    Hydrogeomorphic, vegetative, and biogeochemical processes interact in floodplains resulting in great complexity that provides opportunities to better understand linkages among physical and biological processes in ecosystems. Floodplains and their associated river systems are structured by four dimensional gradients of hydrogeomorphology: longitudinal, lateral, vertical, and temporal components. These four dimensions create dynamic hydrologic and geomorphologic mosaics that have a large imprint on the vegetation and nutrient biogeochemistry of floodplains. Plant physiology, population dynamics, community structure, and productivity are all very responsive to floodplain hydrogeomorphology. The strength of this relationship between vegetation and hydrogeomorphology is evident in the use of vegetation as an indicator of hydrogeomorphic processes. However, vegetation also influences hydrogeomorphology by modifying hydraulics and sediment entrainment and deposition that typically stabilize geomorphic patterns. Nitrogen and phosphorus biogeochemistry commonly influence plant productivity and community composition, although productivity is not limited by nutrient availability in all floodplains. Conversely, vegetation influences nutrient biogeochemistry through direct uptake and storage as well as production of organic matter that regulates microbial biogeochemical processes. The biogeochemistries of nitrogen and phosphorus cycling are very sensitive to spatial and temporal variation in hydrogeomorphology, in particular floodplain wetness and sedimentation. The least studied interaction is the direct effect of biogeochemistry on hydrogeomorphology, but the control of nutrient availability over organic matter decomposition and thus soil permeability and elevation is likely important. Biogeochemistry also has the more documented but indirect control of hydrogeomorphology through regulation of plant biomass. In summary, the defining characteristics of floodplain ecosystems

  16. Radiation and the vegetable industry

    International Nuclear Information System (INIS)

    Roberts, P.B.


    The possible uses of irradiation in the vegetable industry are considered. Interest has been increasing because of possible bans on chemical fumigants and clearance of irradiation as an acceptable process, up to certain dose limits, by Codex Alimentarius and the US FDA. Inhibition of sprouting in potatoes and onions would be one possibility for exploitation. However, the main incentive for vegetable irradiation would be as a quarantine treatment for exported products. The shelf-life of a few vegetables could also be increased by combining radiation with heat treatments. Costs in New Zealand and consumer attitudes are briefly considered


    Directory of Open Access Journals (Sweden)

    Giuseppe Bombino


    Full Text Available The complex hydrogeomorphological processes within the active channel of rivers strongly influence riparian vegetation development and organization, particularly in mountain streams where such processes can be remarkably impacted by engineering control works. In four mountain reaches of Calabrian fiumaras we analyze, through previously arranged methods (integrated by a multivariate statistic analysis, the relationships among hydrogeomorphological river characteristics and structure and the development of riparian vegetation within the active channel in transects located in proximity of check dams and in less disturbed sites. The results of this study demonstrate clear and relevant contrasts, due to the presence of check dams, in the physical and vegetation properties of upstream, downstream and intermediate sites around check dams. The multivariate statistical approach through the Principal Component Analysis (PCA highlighted evident relationships in all transects between groups of physical and vegetation properties. The regression analysis performed between the vegetation properties and the width:depth ratio or the specific discharge showed very different relationships between groups of transects, due to evident changes in channel morphology and in flow regime locally induced by check dams. Overall we have shown that check dams have far reaching effects in the extent and development of riparian vegetation of mountain torrent reaches, which extend far beyond physical adjustments to changed morphological, hydraulic and sedimentary conditions.

  18. Análise fitossociológica de um remanescente de vegetação na microbacia do Córrego Criminoso (Bacia do Rio Taquari, Coxim, MS, Brasil: subsídios para a recomposição da vegetação Phytosociological analysis of a vegetation remnant in the Córrego Criminoso Basin (Taquari River Basin, Coxim District, Mato Grosso do Sul, Brazil: data for vegetation recovery studies

    Directory of Open Access Journals (Sweden)

    Adriana Maria Güntzel


    Full Text Available O objetivo deste estudo foi realizar a análise florística e fitossociológica preliminar em um remanescente de vegetação na área de entorno do Córrego Criminoso, visando subsidiar futuros projetos de recomposição da vegetação. A área total do remanescente foi determinada com o auxílio de GPS e dos programas Pathfinder e Autocad. Amostragens de indivíduos com CAP maior ou igual a 20 cm foram realizadas em 20 parcelas de 300 m² distribuídas na área. Foram encontradas 26 famílias botânicas contendo 36 gêneros e 49 espécies. A família Leguminosae foi a mais rica em espécies, seguida da família Annonaceae. A espécie Xylopia aromatica foi a mais freqüente, apresentando valores de IVI e IVC de 99,77 e 85,73, respectivamente. Observou-se que mais de 50% das espécies presentes na área são pioneiras ou secundárias, sendo cinco consideradas típicas de matas ciliares: Tapirira guianenses, Cecropia pachystachya, Terminalia argentea, Ocotea pulchellae e Luehea grandiflora. O remanescente de vegetação do entorno do Córrego Criminoso encontra-se fortemente degradado, necessitando de ações de manejo específicos nos fragmentos vegetados e nas áreas destituídas de vegetação, cujas recomendações são propostas.The aim of this study was to complete a preliminary, floristic, phytosociological analyses of a vegetation remnant in the Criminoso Stream Basin, in order to provide data for future projects focusing on vegetation recovery. The total area of the remnant was determined using a GPS and the software Pathfinder and Autocad. Samples of individuals larger or equal to 20 cm CBH were made in 20 quadrats that were 300 m². Thirty-six genera and 49 species, within 26 botanical families, were found. The family Leguminosae was the richest in species, followed by the Annonaceae. Xylopia aromatica was the most frequent species, presenting values of IVI and IVC of 99.77 and 85.73, respectively. More than 50% of the species present

  19. Nitrogen retention in river corridors: European perspective

    Energy Technology Data Exchange (ETDEWEB)

    Haycock, N [Dept. of Agriculture and Water Management, Silsoe College, Cranfield Institute of Technology (United Kingdom); Pinay, G [CERR/CNRS, Toulouse (France); Walker, Charles [SBEG, Inst. of Ecology, Lund Univ. (Sweden)


    The problem of nitrogen pollution in European surface- and groundwaters has become a focus of recent European and Scandinavian directives, with legislation calling for a 50% reduction of N losses by the years 1995 and 2000, respectively. This paper provides a conceptual framework upon which management strategies to reduce losses of diffuse nitrogen pollution to surface waters may be based. The control of nitrogen pollution may take place through an increase in the complexity of the landscape, not throughout the catchment area, but rather in specific zones, the river corridor in particular. Within river corridors, riparian areas have been recognized globally for their value as nutrient removal ''buffer systems''. Studies have identified vegetation uptake and microbial denitrification as the primary mechanisms responsible for N removal in these systems. For these processes to function optimally on an annual basis, both vegetation and water regime must be managed. The establishment and management of riparian buffer zones in suitable places within river corridors, will provide a stable and sustainable water-protection function. This will complement future nitrogen input control strategies, needed for both the long-term protection of groundwater and surface waters in Europe as a whole, and for the proposed 50% reduction in nitrogen loading to the Baltic and North Sea coastal waters by the turn of the century. 52 refs, 5 figs

  20. Vegetation structure characteristics and relationships of Kalahari woodlands and savannas

    CSIR Research Space (South Africa)

    Privette, JL


    Full Text Available modeling has become widespread (e.g., Potter et al., 1993, 1998; Sellers et al., 1996). Nevertheless, knowledge of vegetation canopy struc- ture remains incomplete in many remote areas, such as sub-Saharan Africa. First, comparatively small changes... 929 460 Colophospermum mopane woodland with patches of Terminalia sericea thicket Harry Oppenheimer Okavango Research Centre; Measurements were 3km east of a permanent flux tower 23.591E Okwa River Crossing, Botswana 22.411S 1089 407 Open Kalahari...

  1. Allegheny County Major Rivers (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  2. Mitigation and enhancement techniques for the Upper Mississippi River system and other large river systems (United States)

    Schnick, Rosalie A.; Morton, John M.; Mochalski, Jeffrey C.; Beall, Jonathan T.


    Extensive information is provided on techniques that can reduce or eliminate the negative impact of man's activities (particularly those related to navigation) on large river systems, with special reference to the Upper Mississippi River. These techniques should help resource managers who are concerned with such river systems to establish sound environmental programs. Discussion of each technique or group of techniques include (1) situation to be mitigated or enhanced; (2) description of technique; (3) impacts on the environment; (4) costs; and (5) evaluation for use on the Upper Mississippi River Systems. The techniques are divided into four primary categories: Bank Stabilization Techniques, Dredging and Disposal of Dredged Material, Fishery Management Techniques, and Wildlife Management Techniques. Because techniques have been grouped by function, rather than by structure, some structures are discussed in several contexts. For example, gabions are discussed for use in revetments, river training structures, and breakwaters. The measures covered under Bank Stabilization Techniques include the use of riprap revetments, other revetments, bulkheads, river training structures, breakwater structures, chemical soil stabilizers, erosion-control mattings, and filter fabrics; the planting of vegetation; the creation of islands; the creation of berms or enrichment of beaches; and the control of water level and boat traffic. The discussions of Dredging and the Disposal of Dredged Material consider dredges, dredging methods, and disposal of dredged material. The following subjects are considered under Fishery Management Techniques: fish attractors; spawning structures; nursery ponds, coves, and marshes; fish screens and barriers; fish passage; water control structures; management of water levels and flows; wing dam modification; side channel modification; aeration techniques; control of nuisance aquatic plants; and manipulated of fish populations. Wildlife Management

  3. Vegetation - McKenzie Preserve [ds703 (United States)

    California Natural Resource Agency — The California Native Plant Society (CNPS) Vegetation Program produced a vegetation map and classification for approximately 11,600 acres primarily within Millerton...

  4. Quantification of exchangeable and non-exchangeable organically bound tritium (OBT) in vegetation

    International Nuclear Information System (INIS)

    Kim, S.B.; Korolevych, V.


    The objective of this study is to quantify the relative amounts of exchangeable organically bound tritium (OBT) and non-exchangeable OBT in various vegetables. A garden plot at Perch Lake, where tritium levels are slightly elevated due to releases of tritium from a nearby nuclear waste management area and Chalk River Laboratories (CRL) operations, was used to cultivate a variety of vegetables. Five different kinds of vegetables (lettuce, cabbage, tomato, radish and beet) were studied. Exchangeable OBT behaves like tritium in tissue free water in living organisms and, based on past measurements, accounts for about 20% of the total tritium in dehydrated organic materials. In this study, the percentage of the exchangeable OBT was determined to range from 20% to 57% and was found to depend on the type of vegetables as well as the sequence of the plants exposure to HTO. -- Highlights: ► This study was to quantify the amount of exchangeable OBT compared to non-exchangeable OBT in vegetables. ► The percentage of exchangeable OBT varied between vegetable types and HTO exposure conditions. ► Exchangeable OBT varied from 20 to 36% in un-treated vegetables and from 30 to 57% in treated vegetables

  5. Abrupt vegetation transitions characterise long-term Amazonian peatland development (United States)

    Roucoux, K. H.; Baker, T. R.; Gosling, W. D.; Honorio Coronado, E.; Jones, T. D.; Lahteenoja, O.; Lawson, I. T.


    Recent investigations of wetlands in western Amazonia have revealed the presence of extensive peatlands with peat deposits of up to 8 m-thick developing under a variety of vegetation types (Lähteenoja et al. 2012). Estimated to cover 150,000 km2 (Schulman et al. 1999), these peatlands make a valuable contribution to landscape and biological diversity and represent globally important carbon stores. In order to understand the processes leading to peat formation, and the sensitivity of these environments to future climatic change, it is necessary to understand their long-term history. The extent to which peatland vegetation changes over time, the stability of particular communities, the controls on transitions between vegetation types and how these factors relate to the accumulation of organic matter are not yet known. We report the first attempt to establish the long-term (millennial scale) vegetation history of a recently-described peatland site: Quistococha, a palm swamp, or aguajal, close to Iquitos in northern Peru. The vegetation is dominated by Mauritia flexuosa and Mauritiella armata and occupies a basin which is thought to be an abandoned channel of the River Amazon. We obtained a 4 m-long peat sequence from the deepest part of the basin. AMS-radiocarbon dating yielded a maximum age of 2,212 cal yr BP for the base of the peat, giving an average accumulation rate of 18 cm per century. Below the peat are 2 m of uniform, largely inorganic pale grey clays of lacustrine origin, which are underlain by an unknown thickness of inorganic sandy-silty clay of fluvial origin. Pollen analysis, carried out at c. 88-year intervals, shows the last 2,212 years to be characterised by the development of at least four distinct vegetation communities, with peat accumulating throughout. The main phases were: (1) Formation of Cyperaceae (sedge) fen coincident with peat initiation; (2) A short-lived phase of local Mauritia/Mauritiella development; (3) Development of mixed wet

  6. Vegetation - Lassen Foothills [ds564 (United States)

    California Natural Resource Agency — In 2007 Aerial Information Systems, Inc. (AIS) was contracted by the California Native Plant Society (CNPS) to produce a vegetation map for approximately 100,000...

  7. in Leafy Vegetable and Pharmaceutical

    African Journals Online (AJOL)


    successfully employed for the determination of copper (II) in leafy vegetable and pharmaceutical samples. ... Our previous studies of transition metal ions such as zinc, cobalt and ..... A new method for extractive photometric determination of.

  8. Buffers and vegetative filter strips (United States)

    Matthew J. Helmers; Thomas M. Isenhart; Michael G. Dosskey; Seth M. Dabney


    This chapter describes the use of buffers and vegetative filter strips relative to water quality. In particular, we primarily discuss the herbaceous components of the following NRCS Conservation Practice Standards.

  9. Flowing with Rivers (United States)

    Anderson, Heather


    This article describes a lesson in which students compare how artists have depicted rivers in paintings, using different styles, compositions, subject matter, colors, and techniques. They create a watercolor landscape that includes a river. Students can learn about rivers by studying them on site, through environmental study, and through works of…

  10. Restoration of hard mast species for wildlife in Missouri using precocious flowering oak in the Missouri River floodplain, USA (United States)

    B. C. Grossman; M. A. Gold; Daniel C. Dey


    Increased planting of hard mast oak species in the Lower Missouri River floodplain is critical as natural regeneration of oak along the Upper Mississippi and Lower Missouri Rivers has been limited following major flood events in 1993 and 1995. Traditional planting methods have limited success due to frequent flood events, competition from faster growing vegetation and...

  11. Long-term decrease in satellite vegetation indices in response to environmental variables in an iconic desert riparian ecosystem: the Upper San Pedro, Arizona, United States (United States)

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


    The Upper San Pedro River is one of the few remaining undammed rivers that maintain a vibrant riparian ecosystem in the southwest United States. However, its riparian forest is threatened by diminishing groundwater and surface water inputs, due to either changes in watershed characteristics such as changes in riparian and upland vegetation, or human activities such as regional groundwater pumping. We used satellite vegetation indices to quantify the green leaf density of the groundwater-dependent riparian forest from 1984 to 2012. The river was divided into a southern, upstream (mainly perennial flow) reach and a northern, downstream (mainly intermittent and ephemeral flow) reach. Pre-monsoon (June) Landsat normalized difference vegetation index (NDVI) values showed a 20% drop for the northern reach (P  0·05). NDVI and enhanced vegetation index values were positively correlated (P deterioration of the riparian forest in the northern reach.

  12. Application of two quality indices as monitoring and management tools of rivers. Case study: the Imera Meridionale River, Italy. (United States)

    Bonanno, Giuseppe; Lo Giudice, Rosa


    On the basis of the European Water Framework Directive (2000/60), the water resources of the member states of the European Community should reach good quality standards by 2015. Although such regulations illustrate the basic points for a comprehensive and effective policy of water monitoring and management, no practical tools are provided to face and solve the issues concerning freshwater ecosystems such as rivers. The Italian government has developed a set of regulations as adoption of the European Directive but failed to indicate feasible procedures for river monitoring and management. On a local scale, Sicilian authorities have implemented monitoring networks of watersheds, aiming at describing the general conditions of rivers. However, such monitoring programs have provided a relatively fragmentary picture of the ecological conditions of the rivers. In this study, the integrated use of environmental quality indices is proposed as a methodology able to provide a practical approach to river monitoring and management. As a case study, the Imera Meridionale River, Sicily's largest river, was chosen. The water quality index developed by the U.S. National Sanitation Foundation and the floristic quality index based on the Wilhelm method were applied. The former enabled us to describe the water quality according to a spatial-temporal gradient, whereas the latter focused on the ecological quality of riparian vegetation. This study proposes a holistic view of river ecosystems by considering biotic and abiotic factors in agreement with the current European regulations. How the combined use of such indices can guide sustainable management efforts is also discussed.


    Directory of Open Access Journals (Sweden)



    Full Text Available The vegetation of a forest-steppe type from a part of the river Buzău Basin is presented in this paper. After a short presentation of the natural conditions of the forest Crivineni (near the village Valea Lupului, Buzău county, we are making an analysis of the present-day vegetation, as well as the coenotaxons identified by us in that forest.

  14. Handling Procedures of Vegetable Crops (United States)

    Perchonok, Michele; French, Stephen J.


    The National Aeronautics and Space Administration (NASA) is working towards future long duration manned space flights beyond low earth orbit. The duration of these missions may be as long as 2.5 years and will likely include a stay on a lunar or planetary surface. The primary goal of the Advanced Food System in these long duration exploratory missions is to provide the crew with a palatable, nutritious, and safe food system while minimizing volume, mass, and waste. Vegetable crops can provide the crew with added nutrition and variety. These crops do not require any cooking or food processing prior to consumption. The vegetable crops, unlike prepackaged foods, will provide bright colors, textures (crispy), and fresh aromas. Ten vegetable crops have been identified for possible use in long duration missions. They are lettuce, spinach, carrot, tomato, green onion, radish, bell pepper, strawberries, fresh herbs, and cabbage. Whether these crops are grown on a transit vehicle (e.g., International Space Station) or on the lunar or planetary surface, it will be necessary to determine how to safely handle the vegetables while maintaining acceptability. Since hydrogen peroxide degrades into water and oxygen and is generally recognized as safe (GRAS), hydrogen peroxide has been recommended as the sanitizer. The objective of th is research is to determine the required effective concentration of hydrogen peroxide. In addition, it will be determined whether the use of hydrogen peroxide, although a viable sanitizer, adversely affects the quality of the vegetables. Vegetables will be dipped in 1 % hydrogen peroxide, 3% hydrogen peroxide, or 5% hydrogen peroxide. Treated produce and controls will be stored in plastic bags at 5 C for up to 14 days. Sensory, color, texture, and total plate count will be measured. The effect on several vegetables including lettuce, radish, tomato and strawberries has been completed. Although each vegetable reacts to hydrogen peroxide differently, the

  15. Evaluation of urban river landscape design rationality based on AHP

    Directory of Open Access Journals (Sweden)

    Qiao Lifang


    Full Text Available An evaluation model for the rationality of the landscape design of urban rivers was established with the analytic hierarchy process (AHP method so as to provide a foundation for updating the landscape design of urban rivers. The evaluation system was divided into four layers, including the target layer, the comprehensive layer, the element layer, and the index layer. Each layer was made of different indices. The evaluation standards for each index were also given in this paper. This evaluation model was proved tenable through its application to the landscape design rationality evaluation of the Weihe River in Xinxiang City of Henan Province. The results show that the water quality, space, activity, facility, community, width of vegetation, sense of beauty and water content are among the most influential factors and should be considered the main basis for evaluating the rationality of the landscape design of urban rivers.

  16. River basin administration (United States)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  17. Coupled hydrogeomorphic and woody-seedling responses to controlled flood releases in a dryland river (United States)

    Wilcox, Andrew C.; Shafroth, Patrick B.


    Interactions among flow, geomorphic processes, and riparian vegetation can strongly influence both channel form and vegetation communities. To investigate such interactions, we took advantage of a series of dam-managed flood releases that were designed in part to maintain a native riparian woodland system on a sand-bed, dryland river, the Bill Williams River, Arizona, USA. Our resulting multiyear flow experiment examined differential mortality among native and nonnative riparian seedlings, associated flood hydraulics and geomorphic changes, and the temporal evolution of feedbacks among vegetation, channel form, and hydraulics. We found that floods produced geomorphic and vegetation responses that varied with distance downstream of a dam, with scour and associated seedling mortality closer to the dam and aggradation and burial-induced mortality in a downstream reach. We also observed significantly greater mortality among nonnative tamarisk (Tamarix) seedlings than among native willow (Salix gooddingii) seedlings, reflecting the greater first-year growth of willow relative to tamarisk. When vegetation was small early in our study period, the effects of vegetation on flood hydraulics and on mediating flood-induced channel change were minimal. Vegetation growth in subsequent years resulted in stronger feedbacks, such that vegetation's stabilizing effect on bars and its drag effect on flow progressively increased, muting the geomorphic effects of a larger flood release. These observations suggest that the effectiveness of floods in producing geomorphic and ecological changes varies not only as a function of flood magnitude and duration, but also of antecedent vegetation density and size.

  18. Morphodynamic Response of the Unregulated Yampa River at Deerlodge to the 2011 Flood (United States)

    Wheaton, J. M.; Scott, M.; Perkins, D.; DeMeurichy, K.


    The Yampa River, a tributary to the Green River, is the last undammed major tributary in the upper Colorado River Basin. The Yampa River at Deerlodge is actively braiding in an unconfined park valley setting, just upstream of the confined Yampa Canyon in Dinosaur National Monument. Deerlodge is a critical indicator site, which is monitored closely for signs of potential channel narrowing and associated invasions of non-native tamarisk or salt cedar (Tamarix) by the National Park Service's Northern Colorado Plateau Network (NPS-NCPN). Like many rivers draining the Rockies, the Yampa was fed by record snowpack in this year's spring runoff and produced the second largest flood of record at 748 cms (largest food of record was 940 cms in1984). In contrast to most major rivers in the Colorado Basin, which are now dammed, the Yampa's natural, unregulated floods are thought to be of critical importance in rejuvenating the floodplain and reorganizing habitat in a manner favorable to native riparian vegetation and unfavorable to tamarisk. As part of the Big Rivers Monitoring Protocol, a 1.5 km reach of the braided river was surveyed with sub-centimeter resolution ground-based LiDaR and a total station in September of 2010 and was resurveyed after the 2011floods. The ground-based LiDaR captures the vegetation as well as topography. Additionally, vegetation surveys were performed to identify plant species present, percent covers and relative abundance before and after the flood. The Geomorphic Change Detection software was used to distinguish the real net changes from noise and segregate the budget by specific mechanisms of geomorphic change associated with different channel and vegetative patterns. This quantitative study of the morphodynamic response to a major flood highlights a critical potential positive feedback the flood plays on native riparian vegetation recruitment and potential negative feedback on non-native tamarisk.

  19. [Responses of vegetation changes to climatic variations in Panxi area based on the MODIS multispectral data]. (United States)

    Shao, Huai-Yong; Wu, Jin-Hui; Liu, Meng; Yang, Wu-Nian


    It is an important research area to quantitatively studying the relationship between global climatic change and vegetation change based on the remote sensing technology. Panxi area is the ecological barrier of the upper reaches of the Yangtze River, and it is essential for the stability of the ecological environment of Sichuan as well as that of the whole China. The present article analyzes the vegetation change in 2001-2008 and the relationship between vegetation change and climatic variations of Panxi area, based on MODIS multispectral data and meteorological data. The results indicate that NDVI is positively correlated with temperature and precipitation. The precipitation is the major factor that affects the change of vegetation in the Panxi region and the trend of NDVI is similar with autumn precipitation; while at the same time the influence of climate has a one-month-time-lag.

  20. Quantification of exchangeable and non-exchangeable organically bound tritium (OBT) in vegetation. (United States)

    Kim, S B; Korolevych, V


    The objective of this study is to quantify the relative amounts of exchangeable organically bound tritium (OBT) and non-exchangeable OBT in various vegetables. A garden plot at Perch Lake, where tritium levels are slightly elevated due to releases of tritium from a nearby nuclear waste management area and Chalk River Laboratories (CRL) operations, was used to cultivate a variety of vegetables. Five different kinds of vegetables (lettuce, cabbage, tomato, radish and beet) were studied. Exchangeable OBT behaves like tritium in tissue free water in living organisms and, based on past measurements, accounts for about 20% of the total tritium in dehydrated organic materials. In this study, the percentage of the exchangeable OBT was determined to range from 20% to 57% and was found to depend on the type of vegetables as well as the sequence of the plants exposure to HTO. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  1. East African Cenozoic vegetation history. (United States)

    Linder, Hans Peter


    The modern vegetation of East Africa is a complex mosaic of rainforest patches; small islands of tropic-alpine vegetation; extensive savannas, ranging from almost pure grassland to wooded savannas; thickets; and montane grassland and forest. Here I trace the evolution of these vegetation types through the Cenozoic. Paleogene East Africa was most likely geomorphologically subdued and, as the few Eocene fossil sites suggest, a woodland in a seasonal climate. Woodland rather than rainforest may well have been the regional vegetation. Mountain building started with the Oligocene trap lava flows in Ethiopia, on which rainforest developed, with little evidence of grass and none of montane forests. The uplift of the East African Plateau took place during the middle Miocene. Fossil sites indicate the presence of rainforest, montane forest and thicket, and wooded grassland, often in close juxtaposition, from 17 to 10 Ma. By 10 Ma, marine deposits indicate extensive grassland in the region and isotope analysis indicates that this was a C 3 grassland. In the later Miocene rifting, first of the western Albertine Rift and then of the eastern Gregory Rift, added to the complexity of the environment. The building of the high strato-volcanos during the later Mio-Pliocene added environments suitable for tropic-alpine vegetation. During this time, the C 3 grassland was replaced by C 4 savannas, although overall the extent of grassland was reduced from the mid-Miocene high to the current low level. Lake-level fluctuations during the Quaternary indicate substantial variation in rainfall, presumably as a result of movements in the intertropical convergence zone and the Congo air boundary, but the impact of these fluctuations on the vegetation is still speculative. I argue that, overall, there was an increase in the complexity of East African vegetation complexity during the Neogene, largely as a result of orogeny. The impact of Quaternary climatic fluctuation is still poorly understood

  2. Anuran community composition along two large rivers in a tropical disturbed landscape

    Directory of Open Access Journals (Sweden)

    Mauricio Almeida-Gomes


    Full Text Available In this study we evaluated how anuran species were distributed in riparian habitats along two large rivers. Sampling was carried out between January and March 2012 in the municipality of Cachoeiras de Macacu, state of Rio de Janeiro. We delimited 20 plots along each river, ten in portions inside the forest of the Reserva Ecológica de Guapiaçu (REGUA, and with comparatively greater amount of forest cover, and ten outside REGUA, with comparatively lesser forest cover surrounding the rivers. We recorded 70 individuals from 14 frog species in the Manoel Alexandre River and 63 individuals from 15 frog species in the Guapiaçu River. The most abundant species in both rivers was Cycloramphus brasiliensis (Steindachner, 1864, and it was more abundant in sections with greater amount of forest cover. This information, coupled with the occurrence of species that are more adapted to open and more disturbed habitats in river sections that harbor lesser riparian vegetation, help to explain differences in amphibian species composition between river sections with greater and lesser forest cover. The results of our study highlight the importance of preserving riparian vegetation associated with rivers in the Atlantic Forest for the conservation of amphibians.

  3. Tamarisk and river-channel management (United States)

    Graf, William L.


    Tamarisk (Tamarix chinensis, Lour.) an artificially introduced tree, has become a most common species in many riparian vegetation communities along the rivers of the western United States. On the Salt and Gila rivers of central Arizona, the plant first appeared in the early 1890s, and by 1940 it grew in dense thickets that posed serious flood-control problems by substantially reducing the capacities of major channels. Since 1940 its distribution and density in central Arizona have fluctuated in response to combined natural processes and human management. Groundwater levels, channel waters, floods, irrigation return waters, sewage effluent, and sedimentation behind retention and diversion works are major control mechanisms on the growth of tamarisk; on a regional scale of analysis, groundwater levels are the most significant under present conditions.

  4. Chapter 3: Status and trends of vegetation (United States)

    James M. Guldin; Frank R. Thompson; Lynda L. Richards; Kyra C. Harper


    This chapter provides information about the vegetation cover of the Assessment area. The types and areal extent of vegetation in the Highlands are of interest for many reasons. Vegetation cover largely determines the availability of habitat for terrestrial animals, plants, and other organisms. Vegetation cover strongly influences what uses {e.g., timber, forage,...

  5. Vegetables and other core food groups

    NARCIS (Netherlands)

    Poelman, Astrid A.M.; Delahunty, Conor M.; Graaf, de Kees


    Vegetables are the food category least liked by children. This research investigated the sensory properties of vegetables vis-a-vis other core foods that comprise children's diets, to determine to what degree low acceptance of vegetables can be attributed to sensory properties. Vegetables (n =

  6. 18 CFR 1304.203 - Vegetation management. (United States)


    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Vegetation management...-Owned Residential Access Shoreland § 1304.203 Vegetation management. No vegetation management shall be approved on TVA-owned Residential Access Shoreland until a Vegetation Management Plan meeting the...

  7. Lysimeter study of vegetative uptake from saltstone

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, C.E. Jr.


    At the Savannah River Site, liquid, low-level nuclear waste will be disposed of by incorporating the waste in concrete, a wasteform called saltstone. Saltstone monoliths will then be buried in the earth. To study the potential uptake of radionuclides by trees and other plants growing in the soil in the area containing buried saltstone, a lysimeter study has been in progress since 1984. Thirty two lysimeters were designed, constructed, and filled with soil. Saltstone samples, containing the liquid, low-level supernate from the tank 50 in-tank precipitation demonstration, were buried in some of the lysimeters. Other lysimeters, not containing saltstone, were used as controls. Crops, grass, and trees were planted in the lysimeters and sampled periodically to determine radionuclide concentrations. Water samples were also collected from the lysimeter sumps and analyzed for radionuclide content. This report documents the results of vegetative and lysimeter sump water measurements from the beginning of the project in November of 1984 through September of 1989. 6 refs., 22 figs., 6 tabs.

  8. Experimental Salix shoot and root growth statistics on the alluvial sediment of a restored river corridor (United States)

    Pasquale, N.; Perona, P.; Verones, F.; Francis, R.; Burlando, P.


    River restoration projects encompass not only the amelioration of flood protection but also the rehabilitation of the riverine ecosystem. However, the interactions and feedbacks between river hydrology, riparian vegetation and aquifer dynamics are still poorly understood. Vegetation interacts with river hydrology on multiple time scales. Hence, there is considerable interest in understanding the morphodynamics of restored river reaches in relation to the characteristics of vegetation that may colonize the bare sediment, and locally stabilize it by root anchoring. In this paper we document results from a number of ongoing experiments within the project RECORD (Restored CORridor Dynamics, sponsored by CCES - - and Cantons Zurich and Thurgau, CH). In particular, we discuss both the above and below ground biomass growth dynamics of 1188 Salix cuttings (individual and group survival rate, growth of the longest shoots and number of branches and morphological root analysis) in relation to local river hydrodynamics. Cuttings were organized in square plots of different size and planted in spring 2009 on a gravel island of the restored river section of River Thur in Switzerland. By periodical monitoring the plots we obtained a detailed and quite unique set of data, including root statistics of uprooted samples derived from image analysis from a high-resolution scanner. Beyond describing the survival rate dynamics in relation to river hydrology, we show the nature and strength of correlations between island topography and cutting growth statistics. In particular, by root analysis and by comparing empirical histograms of the vertical root distribution vs satured water surface in the sediment, we show that main tropic responses on such environment are oxytropism, hydrotropism and thigmotropism. The main factor influencing the survival rate is naturally found in erosion by floods, of which we also give an interesting example that helps demonstrate the role of river

  9. Mutation breeding in vegetable crops

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Takashi


    Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting this situation, the demand for breeding is diversified and characteristic. The present status of mutation breeding of vegetables is not yet well under way, but reports of about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation are compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. Results obtained in Japan include: burdocks as an example to gamma ray irradiation of seeds; tomatoes as an example of inducing compound resistance against disease injury; and lettuce as an example of internal beta irradiation. (Kako, I.).

  10. Mutation breeding in vegetable crops

    International Nuclear Information System (INIS)

    Yamaguchi, Takashi


    Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting the situation like this, the demand for breeding is diversified and characteristic, and the case of applying mutation breeding seems to be many. The present status of the mutation breeding of vegetables is not yet well under way, but about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation were compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. As the results obtained in Japan, burdocks as an example of gamma ray irradiation to seeds, tomatoes as an example of inducing the compound resistance against disease injury and lettuces as an example of internal beta irradiation are reported. (Kako, I.)

  11. Controles hidrogeomorfológicos nas unidades vegetacionais da planície aluvial do rio Araguaia, Brasil - DOI: 10.4025/actascibiolsci.v30i4.5871 Hydro-geomorphologic controls in the vegetation of the Araguaia river floodplain, Brazil - DOI: 10.4025/actascibiolsci.v30i4.5871

    Directory of Open Access Journals (Sweden)

    Samia Aquino


    Full Text Available A existência de diferentes tipologias vegetais na planície aluvial do médio Araguaia apresenta um padrão de distribuição determinado pela dinâmica fluvial do canal e pelas características morfossedimentares das unidades que formam a planície aluvial. O objetivo deste trabalho foi discutir como a dinâmica fluvial atua nos processos de sucessão vegetacional, considerando os processos de erosão e deposição, dentro de um curto intervalo temporal, e a dinâmica de cheias. O processamento de informações dos mapas das unidades morfossedimentares da planície e das unidades vegetacionais resultou no mapa de unidades morfovegetacionais. Verificou-se que as unidades vegetacionais se distribuem e compõem, de modo diversificado, um mosaico vegetacional pela planície. Entre 1965 e 1997, a ação dos processos erosivos, nas margens do canal que consomem a planície aluvial, tem removido principalmente vegetações arbóreas de grande porte, e as altas taxas de sedimentação contribuem para a formação da unidade geomorfológica mais jovem da planície, que é colonizada, sobretudo, por espécies herbáceas.The existence of different vegetable typologies in the alluvial plains of the middle Araguaia presents a pattern of distribution determined by the fluvial dynamic of the channel and the type of sediments that form different units of the alluvial plain. The purpose of this study was to discuss how the fluvial processes acts in vegetation succession, considering the erosive and sedimentary activities within a short period of time, as well as the flood dynamic. The combined information from morphosedimentary unit maps of the alluvial plain and the vegetation units allows the elaboration of the map of morphosedimentary units. It was possible to verify that the vegetation units were distributed in a diversified way along the alluvial plain, composing a vegetation mosaic. Between 1965 and 1997, the action of the erosive processes in the banks

  12. Long-term vegetation monitoring for different habitats in floodplains

    Directory of Open Access Journals (Sweden)

    LANG Petra


    Full Text Available A floodplain-restoration project along the Danube between Neuburg and Ingolstadt (Germany aims to bring back water and sediment dynamic to the floodplain. The accompanied long-term monitoring has to document the changes in biodiversity related to this new dynamics. Considerations on and results of the vegetation monitoring concept are documented in this paper. In a habitat rich ecosystem like a floodplain different habitats (alluvial forest, semi-aquatic/aquatic sites have different demands on the sampling methods. Therefore, different monitoring designs (preferential, random, systematic, stratified random and transect sampling are discussed and tested for their use in different habitat types of the floodplain. A stratified random sampling is chosen for the alluvial forest stands, as it guarantees an equal distribution of the monitoring plots along the main driving factors, i.e. influence of water. The parameters distance to barrage, ecological flooding, height above thalweg and distance to the new floodplain river are used for stratifying and the plots are placed randomly into these strata, resulting in 117 permanent plots. Due to small changes at the semi-aquatic/aquatic sites a transect sampling was chosen. Further, a rough stratification (channel bed, river bank adjacent floodplain was implemented, which was only possible after the start of the restoration project. To capture the small-scale changes due to the restoration measures on the vegetation, 99 additional plots completed the transect sampling. We conclude that hetereogenous study areas need different monitoring approaches, but, later on, a joint analysis must be possible.

  13. Hydraulic and Vegetative Models of Historic Environmental Conditions Isolate the Role of Riparian Vegetation in Inducing Channel Change (United States)

    Manners, R.; Schmidt, J. C.; Wheaton, J. M.


    An enduring question in geomorphology is the role of riparian vegetation in inducing or exacerbating channel narrowing. It is typically difficult to isolate the role of vegetation in causing channel narrowing, because narrowing typically occurs where there are changes in stream flow, sediment supply, the invasion of non-native vegetation, and sometimes climate change. Therefore, linkages between changes in vegetation communities and changes in channel form are often difficult to identify. We took a mechanistic approach to isolate the role of the invasive riparian shrub tamarisk (Tamarix spp) in influencing channel narrowing in the Colorado River basin. Detailed geomorphic reconstructions of two sites on the Yampa and Green Rivers, respectively, in Dinosaur National Monument show that channel narrowing has been progressive and that tamarisk encroachment has also occurred; at the same time, dams have been constructed, diversions increased, and spring snowmelt runoff has been occurring earlier in spring. We simulated hydraulic and sediment transport conditions during the two largest floods of record -- 1984 and 2011. Two-dimensional hydraulic models were built to reflect these conditions and allowed us to perform sensitivity tests to determine the dominant determinants of the observed patterns of erosion and deposition. Channel and floodplain topography were constrained through detailed stratigraphic analysis, including precise dating of deposits based on dating of buried tamarisk plants in a series of floodplain trenches and pits. We also used historical air photos to establish past channel topography. To parameterize the influence of riparian vegetation, we developed a model that links detailed terrestrial laser scan (TLS) measurements of stand structure and its corresponding hydraulic roughness at the patch scale to reach-scale riparian vegetation patterns determined from airborne LiDaR (ALS). This model, in conjunction with maps of the ages and establishment

  14. Operation of river systems. The Otra river

    International Nuclear Information System (INIS)

    Harby, A.; Vaskinn, K.A.; Wathne, M.; Heggenes, J.; Saltveit, S.J.


    The purpose of the project described in this report was to prepare an operative tool for making decisions about the operation of the power system on the river Otra (Norway) with regard to how this operation might affect the various users of the river system. Above all this affects fish, outdoor life and esthetic values. The connection between water quality and volume of discharge has been examined in a sub project. How suitable parts of the river are as habitats for trout has been simulated on a computer. From field investigation it is concluded that near the Steinfoss power station the physical conditions for trout depend on the operation of the river system. Outdoor life is not much affected downstream Vikeland. 11 refs., 22 figs., 2 tabs

  15. 76 FR 51887 - Safety Zone; Patuxent River, Patuxent River, MD (United States)


    ...-AA00 Safety Zone; Patuxent River, Patuxent River, MD AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone during the ``NAS Patuxent River... held over certain waters of the Patuxent River adjacent to Patuxent River, Maryland from September 1...

  16. Pen Branch Delta and Savannah River Swamp Hydraulic Model

    International Nuclear Information System (INIS)

    Chen, K.F.


    The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions

  17. Temporal reflectance changes in vegetables

    DEFF Research Database (Denmark)

    Dissing, Bjørn Skovlund; Clemmensen, Line Katrine Harder; Ersbøll, Bjarne Kjær


    Quality control in the food industry is often performed by measuring various chemical compounds of the food involved. We propose an imaging concept for acquiring high quality multispectral images to evaluate changes of carrots and celeriac over a period of 14 days. Properties originating...... in the surface chemistry of vegetables may be captured in an integrating sphere illumination which enables the creation of detailed surface chemistry maps with a good combination of spectral and spatial resolutions. Prior to multispectral image recording, the vegetables were prefried and frozen at -30Â......°C for four months. During the 14 days of image recording, the vegetables were kept at +5°C in refrigeration. In this period, surface changes and thereby reflectance properties were very subtle. To describe this small variation we employed advanced statistical techniques to search a large featurespace...


    Directory of Open Access Journals (Sweden)

    M. I. Fedorova


    Full Text Available The main advantage of root vegetables is their unique specificity and high economic importance. The benefits and medicinal properties of root vegetables being highly demanded by the market requirements to the commodity are highlighted in the article. The main directions of breeding program for root vegetable crops, including species of Apiaceae family with carrot, parsnips; Chenopodioideae family with red beet; Brassicaceae family with radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga. Initial breeding accessions of carrot, red beet, radish, Daikon, Raphanus sativus L. var. lobo Sazonova & Stank, turnip and rutabaga have been selected out to be used for breeding program for heterosis. The mf and ms breeding lines were developed, and with the use of them the new gene pool was created. Variety supporting breeding program and methods were also proposed. 

  19. A Modeling Approach for Evaluating the Coupled Riparian Vegetation-Geomorphic Response to Altered Flow Regimes (United States)

    Manners, R.; Wilcox, A. C.; Merritt, D. M.


    The ecogeomorphic response of riparian ecosystems to a change in hydrologic properties is difficult to predict because of the interactions and feedbacks among plants, water, and sediment. Most riparian models of community dynamics assume a static channel, yet geomorphic processes strongly control the establishment and survival of riparian vegetation. Using a combination of approaches that includes empirical relationships and hydrodynamic models, we model the coupled vegetation-topographic response of three cross-sections on the Yampa and Green Rivers in Dinosaur National Monument, to a shift in the flow regime. The locations represent the variable geomorphology and vegetation composition of these canyon-bound rivers. We account for the inundation and hydraulic properties of vegetation plots surveyed over three years within International River Interface Cooperative (iRIC) Fastmech, equipped with a vegetation module that accounts for flexible stems and plant reconfiguration. The presence of functional groupings of plants, or those plants that respond similarly to environmental factors such as water availability and disturbance are determined from flow response curves developed for the Yampa River. Using field measurements of vegetation morphology, distance from the channel centerline, and dominant particle size and modeled inundation properties we develop an empirical relationship between these variables and topographic change. We evaluate vegetation and channel form changes over decadal timescales, allowing for the integration of processes over time. From our analyses, we identify thresholds in the flow regime that alter the distribution of plants and reduce geomorphic complexity, predominately through side-channel and backwater infilling. Simplification of some processes (e.g., empirically-derived sedimentation) and detailed treatment of others (e.g., plant-flow interactions) allows us to model the coupled dynamics of riparian ecosystems and evaluate the impact of

  20. Inter-species competition-facilitation in stochastic riparian vegetation dynamics. (United States)

    Tealdi, Stefano; Camporeale, Carlo; Ridolfi, Luca


    Riparian vegetation is a highly dynamic community that lives on river banks and which depends to a great extent on the fluvial hydrology. The stochasticity of the discharge and erosion/deposition processes in fact play a key role in determining the distribution of vegetation along a riparian transect. These abiotic processes interact with biotic competition/facilitation mechanisms, such as plant competition for light, water, and nutrients. In this work, we focus on the dynamics of plants characterized by three components: (1) stochastic forcing due to river discharges, (2) competition for resources, and (3) inter-species facilitation due to the interplay between vegetation and fluid dynamics processes. A minimalist stochastic bio-hydrological model is proposed for the dynamics of the biomass of two vegetation species: one species is assumed dominant and slow-growing, the other is subdominant, but fast-growing. The stochastic model is solved analytically and the probability density function of the plant biomasses is obtained as a function of both the hydrologic and biologic parameters. The impact of the competition/facilitation processes on the distribution of vegetation species along the riparian transect is investigated and remarkable effects are observed. Finally, a good qualitative agreement is found between the model results and field data. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Numerical study of hydrodynamic and salinity transport processes in the Pink Beach wetlands of the Liao River estuary, China

    Directory of Open Access Journals (Sweden)

    H. Qiao


    Full Text Available Interaction studies of vegetation within flow environments are essential for the determination of bank protection, morphological characteristics and ecological conditions for wetlands. This paper uses the MIKE 21 hydrodynamic and salinity model to simulate the hydrodynamic characteristics and salinity transport processes in the Pink Beach wetlands of the Liao River estuary. The effect of wetland plants on tidal flow in wetland areas is represented by a varying Manning coefficient in the bottom friction term. Acquisition of the vegetation distribution is based on Landsat TM satellites by remote sensing techniques. Detailed comparisons between field observation and simulated results of water depth, salinity and tidal currents are presented in the vegetated domain of the Pink Beach wetlands. Satisfactory results were obtained from simulations of both flow characteristics and salinity concentration, with or without vegetation. A numerical experiment was conducted based on variations in vegetation density, and compared with the tidal currents in non-vegetated areas; the computed current speed decreased remarkably with an increase in vegetation density. The impact of vegetation on water depth and salinity was simulated, and the findings revealed that wetland vegetation has an insignificant effect on the water depth and salinity in this wetland domain. Several stations (from upstream to downstream in the Pink Beach wetlands were selected to estimate the longitudinal variation of salinity under different river runoff conditions; the results showed that salinity concentration decreases with an increase in river runoff. This study can consequently help increase the understanding of favourable salinity conditions for particular vegetation growth in the Pink Beach wetlands of the Liao River estuary. The results also provide crucial guidance for related interaction studies of vegetation, flow and salinity in other wetland systems.

  2. Willingness to pay for environmental improvements in hydropower regulated rivers

    International Nuclear Information System (INIS)

    Kataria, Mitesh


    This paper uses a choice experiment to estimate how Swedish households value different environmental improvements for the hydropower regulated rivers. We obtained clear evidence that Swedish households have preferences for environmental improvement in hydropower regulated waters, at least when the cost is relatively low. Remedial measures that improve the conditions for all of the included environmental attributes i.e. fish, benthic invertebrates, river-margin vegetation and birds were found to have a significant welfare increasing impact. The results can be of value for the implementation of the Water Framework Directives in Sweden, which aims to reform the use of all surface water and ground water in the member states. (author)

  3. Local vegetables in Cameroon: Corchorus species used as a vegetable.

    NARCIS (Netherlands)

    Westphal-Stevels, J.M.C.


    An agro-botanical study of local vegetables in Cameroon is in preparation, including the taxonomy, identity, morphology, agronomy and nutritional value of about 70 species. Corchorus olitorius L. and other edible species of the genus Corchorus L. (Tiliaceae) are part of this study. The wide

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

  5. Water quality assessment of highly polluted rivers in a semi-arid Mediterranean zone Oued Fez and Sebou River (Morocco) (United States)

    Perrin, J. L.; Raïs, N.; Chahinian, N.; Moulin, P.; Ijjaali, M.


    Oued Fez (one of the Sebou River tributaries - Morocco) allowed us to study and quantify the effect of the lack of wastewater treatment on surface water quality in semi-arid hydrological context. The analysis is based on field data collected from June 2009 to December 2011. Concentration and load patterns of nitrogen, phosphorus and chromium (used in the processing of leather) are compared in stable hydrological conditions during low flow and high flow periods in an eight-location sampling network. The Oued Fez and the Sebou River are characterised by severe pollution downstream from the city of Fez, particularly TN (mainly NH4 and Norg), TP (mainly Ppart) and TCr. The most polluted sites are those directly under the influence of domestic and industrial waste water inputs, particularly tannery effluents. Obviously, the concentrations measured at these locations are above all environmental quality standards. Pollutant loads are very heavy in the Sebou River and can contaminate the river course for kilometres. Moreover, as the water of the Sebou River is used for the irrigation of vegetables, serious problems of public health could arise. A better understanding of contaminant dynamics and self-purifying processes in these rivers will help implement actions and steps aimed at improving water quality in the Sebou River, which is the primary water supply source in Morocco and is used for agricultural and industrials purposes as well as for drinking water.

  6. Hydrologic pulses and remaining natural vegetation in Jaú and Jacaré-Pepira watersheds


    Rezende, Jozrael Henriques; Pires, José Salatiel Rodrigues; Mendiondo, Eduardo Mario


    The aim of this work was to study the influence of natural vegetation in two subwatersheds of the Tietê-Jacaré Water Resources Management Unit in São Paulo State on the pulse of their rivers. In Jacaré-Pepira Subwatershed, having higher remaining cover index, pulses were more predictable and had lower amplitude in the study period, indicating less perturbation of the water body and higher resilience of the aquatic ecosystem. Jacaré-Pepira River specific mean discharge was higher than the Q5% ...

  7. Woody riparian vegetation response to different alluvial water table regimes (United States)

    Shafroth, P.B.; Stromberg, J.C.; Patten, D.T.


    Woody riparian vegetation in western North American riparian ecosystems is commonly dependent on alluvial groundwater. Various natural and anthropogenic mechanisms can cause groundwater declines that stress riparian vegetation, but little quantitative information exists on the nature of plant response to different magnitudes, rates, and durations of groundwater decline. We observed groundwater dynamics and the response of Populus fremontii, Salix gooddingii, and Tamarix ramosissima saplings at 3 sites between 1995 and 1997 along the Bill Williams River, Arizona. At a site where the lowest observed groundwater level in 1996 (-1.97 m) was 1.11 m lower than that in 1995 (-0.86 m), 92-100% of Populus and Salix saplings died, whereas 0-13% of Tamarix stems died. A site with greater absolute water table depths in 1996 (-2.55 m), but less change from the 1995 condition (0.55 m), showed less Populus and Salix mortality and increased basal area. Excavations of sapling roots suggest that root distribution is related to groundwater history. Therefore, a decline in water table relative to the condition under which roots developed may strand plant roots where they cannot obtain sufficient moisture. Plant response is likely mediated by other factors such as soil texture and stratigraphy, availability of precipitation-derived soil moisture, physiological and morphological adaptations to water stress, and tree age. An understanding of the relationships between water table declines and plant response may enable land and water managers to avoid activities that are likely to stress desirable riparian vegetation.

  8. Down to the River

    DEFF Research Database (Denmark)

    Wessels, Josepha Ivanka


    Currently there is no coherent or sustainable water cooperation among the five states—Israel, Jordan, Lebanon, Palestinian territories and Syria—that share the Jordan River. Why do people not cooperate on sustainable river basin management, even if it seems the most rational course from the persp......Currently there is no coherent or sustainable water cooperation among the five states—Israel, Jordan, Lebanon, Palestinian territories and Syria—that share the Jordan River. Why do people not cooperate on sustainable river basin management, even if it seems the most rational course from...

  9. Investing in river health. (United States)

    Bennett, J


    Rivers provide society with numerous returns. These relate to both the passive and extractive uses of the resources embodied in river environments. Some returns are manifest in the form of financial gains whilst others are non-monetary. For instance, rivers are a source of monetary income for those who harvest their fish. The water flowing in rivers is extracted for drinking and to water crops and livestock that in turn yield monetary profits. However, rivers are also the source of non-monetary values arising from biological diversity. People who use them for recreation (picnicking, swimming, boating) also receive non-monetary returns. The use of rivers to yield these returns has had negative consequences. With extraction for financial return has come diminished water quantity and quality. The result has been a diminished capacity of rivers to yield (non-extractive) environmental returns and to continue to provide extractive values. A river is like any other asset. With use, the value of an asset depreciates because its productivity declines. In order to maintain the productive capacity of their assets, managers put aside from their profits depreciation reserves that can be invested in the repair or replacement of those assets. Society now faces a situation in which its river assets have depreciated in terms of their capacity to provide monetary and non-monetary returns. An investment in river "repair" is required. But, investment means that society gives up something now in order to achieve some benefit in the future. Society thus has to grapple wih the choice between investing in river health and other investments--such as in hospitals, schools, defence etc. - as well as between investing in river health and current consumption--such as on clothes, food, cars etc. A commonly used aid for investment decision making in the public sector is benefit cost analysis. However, its usefulness in tackling the river investment problem is restricted because it requires all

  10. River and river-related drainage area parameters for site investigation program

    International Nuclear Information System (INIS)

    Blomqvist, P.; Brunberg, A.K.; Brydsten, L.


    In this paper, a number of parameters of importance to a determination of the function of running waters as transport channels for material from the continents to the sea are presented. We have assumed that retention mechanisms of material in the river and in the riparian zone will be covered by special investigations but tried to create a platform for such investigations by quantification of the extension of different main habitats. The choice of parameters has been made so that also the nature conservation value of the river can be preliminary established, and includes a general description of the river type and the inherent ecosystem. The material links directly to that presented in a previous report concerning site investigation programmes for lakes. The parameters have been divided into five groups: 1) The location of the object relative important gradients in the surrounding nature; 2) The river catchment area and its major constituents; 3) The river morphometry; 4) The river ecosystem; 5) Human-induced damages to the river ecosystem. The first two groups, principally based on the climate, hydrology, geology and vegetation of the catchment area, represent parameters that can be used to establish the rarity and representativity of the system, and will in the context of site investigation program be used as a basis for generalisation of the results. The third group, the river morphometry parameters, are standard parameters for the outline of sampling programmes and for calculations of the physical extension of key habitats in the system. The fourth group, the ecosystem of the river, includes physical, chemical and biological parameters required for determination of the influence from the terrestrial ecosystem of the catchment area, nutrient status, distribution of different habitats, and presence of fish in the system. In the context of site investigation program, the parameters in these two groups will be used for budget calculations of the flow of energy and

  11. River and river-related drainage area parameters for site investigation program

    Energy Technology Data Exchange (ETDEWEB)

    Blomqvist, P.; Brunberg, A.K. [Uppsala Univ. (Sweden). Dept. of Limnology; Brydsten, L. [Umeaa Univ. (Sweden). Dept. of Ecology and Environmental Science


    In this paper, a number of parameters of importance to a determination of the function of running waters as transport channels for material from the continents to the sea are presented. We have assumed that retention mechanisms of material in the river and in the riparian zone will be covered by special investigations but tried to create a platform for such investigations by quantification of the extension of different main habitats. The choice of parameters has been made so that also the nature conservation value of the river can be preliminary established, and includes a general description of the river type and the inherent ecosystem. The material links directly to that presented in a previous report concerning site investigation programmes for lakes. The parameters have been divided into five groups: 1) The location of the object relative important gradients in the surrounding nature; 2) The river catchment area and its major constituents; 3) The river morphometry; 4) The river ecosystem; 5) Human-induced damages to the river ecosystem. The first two groups, principally based on the climate, hydrology, geology and vegetation of the catchment area, represent parameters that can be used to establish the rarity and representativity of the system, and will in the context of site investigation program be used as a basis for generalisation of the results. The third group, the river morphometry parameters, are standard parameters for the outline of sampling programmes and for calculations of the physical extension of key habitats in the system. The fourth group, the ecosystem of the river, includes physical, chemical and biological parameters required for determination of the influence from the terrestrial ecosystem of the catchment area, nutrient status, distribution of different habitats, and presence of fish in the system. In the context of site investigation program, the parameters in these two groups will be used for budget calculations of the flow of energy and

  12. Vegetables, Coctails & Reflections / Marco Laimre

    Index Scriptorium Estoniae

    Laimre, Marko, 1968-


    Pealkirja "Vegetables, Coctails & Reflections" kandis Tallinna Kunstihoones 8.04.-28.05.2006 avatud Elin Kardi, Marko Mäetamme, Marco Laimre ja Andres Tali ühisnäitusel "Vägivald ja propaganda" Marco Laimre installatsioon. Marco Laimre esinemine raadiosaates "" Klassikaraadios 16.04.2006

  13. Vegetable Crop Pests. MEP 311. (United States)

    Kantzes, James G.; And Others

    As part of a cooperative extension service series by the University of Maryland, this publication introduces the identification and control of common agricultural pests of vegetable crops. The first of the five sections defines "pest" and "weed" and generally introduces different kinds of pests in the categories of insects,…

  14. Self-crafting vegetable snacks

    NARCIS (Netherlands)

    Raghoebar, Sanne; Kleef, van Ellen; Vet, de Emely


    Purpose: The purpose of this paper is to test whether the IKEA-effect (Norton et al., 2012) – better liking for self-crafted products than for identical products crafted by others – can be exploited to increase liking and consumption of vegetable snacks in children. Design/methodology/approach: A

  15. Flavour release from dried vegetables

    NARCIS (Netherlands)

    Ruth, van S.M.


    The research described in this thesis was focused on the development of an in vitro model system for isolation of volatile compounds from dried vegetables under mouth conditions, such as volume of the mouth, temperature, salivation and mastication. Instrumental analysis of these

  16. Distributed hydrological modelling of the Senegal river basin - model construction and validation

    DEFF Research Database (Denmark)

    Andersen, J.; Refsgaard, J.C.; Jensen, Karsten Høgh


    A modified version of the physically-based distributed MIKE SHE model code was applied to the 375,000 km(2) Senegal River Basin. On the basis of conventional data from meteorological stations and readily accessible databases on topography, soil types, vegetation type, etc. three models with diffe......A modified version of the physically-based distributed MIKE SHE model code was applied to the 375,000 km(2) Senegal River Basin. On the basis of conventional data from meteorological stations and readily accessible databases on topography, soil types, vegetation type, etc. three models...

  17. NDVI-Based Analysis on the Influence of Climate Change and Human Activities on Vegetation Restoration in the Shaanxi-Gansu-Ningxia Region, Central China

    Directory of Open Access Journals (Sweden)

    Shuangshuang Li


    Full Text Available In recent decades, climate change has affected vegetation growth in terrestrial ecosystems. We investigated spatial and temporal patterns of vegetation cover on the Loess Plateau’s Shaanxi-Gansu-Ningxia region in central China using MODIS-NDVI data for 2000–2014. We examined the roles of regional climate change and human activities in vegetation restoration, particularly from 1999 when conversion of sloping farmland to forestland or grassland began under the national Grain-for-Green program. Our results indicated a general upward trend in average NDVI values in the study area. The region’s annual growth rate greatly exceeded those of the Three-North Shelter Forest, the upper reaches of the Yellow River, the Qinling–Daba Mountains, and the Three-River Headwater region. The green vegetation zone has been annually extending from the southeast toward the northwest, with about 97.4% of the region evidencing an upward trend in vegetation cover. The NDVI trend and fluctuation characteristics indicate the occurrence of vegetation restoration in the study region, with gradual vegetation stabilization associated with 15 years of ecological engineering projects. Under favorable climatic conditions, increasing local vegetation cover is primarily attributable to ecosystem reconstruction projects. However, our findings indicate a growing risk of vegetation degradation in the northern part of Shaanxi Province as a result of energy production facilities and chemical industry infrastructure, and increasing exploitation of mineral resources.

  18. Preliminary results of hydrogeologic investigations Humboldt River Valley, Winnemucca, Nevada (United States)

    Cohen, Philip M.


    Most of the ground water of economic importance and nearly all the ground water closely associated with the flow o# the Humboldt River in the. 40-mile reach near Winnemucca, Nev., are in unconsolidated sedimentary deposits. These deposits range in age from Pliocene to Recent and range in character from coarse poorly sorted fanglomerate to lacustrine strata of clay, silt, sand, and gravel. The most permeable deposit consists of sand and gravel of Lake Lahontan age--the so-called medial gravel unit--which is underlain and overlain by fairly impermeable silt and clay also of Lake Lahontan age. The ultimate source of nearly all the water in the study area is precpitation within the drainage basin of the Humboldt River. Much of this water reaches the study, area as flow or underflow of the Humboldt River and as underflow from other valleys tributary to the study area. Little if any flow from the tributary streams in the study area usually reaches the Humboldt River. Most of the tributary streamflow within the study area evaporates or is transpired by vegetation, but a part percolates downward through unconsolidated deposits of the alluvial fans flanking the mountains and move downgradient as ground-water underflow toward the Humboldt River. Areas that contribute significant amounts of ground-water underflow to. the valley of the Humboldt River within the study area are (1) the valley of the Humboldt River upstream from the study area, (2) the Pole Creek-Rock Creek area, (3) Paradise Valley, and (4) Grass Valley and the northwestern slope of the Sonoma Range. The total average underflow from these areas in the period 1949-61 was about 14,000-19,000 acre-feet per year. Much of this underflow discharged into the Humboldt River within the study area and constituted a large part of the base flow of the river. Streamflow in the Humboldt River increases substantially in the early spring, principally because of runoff to the river in the reaches upstream from the study area

  19. Serving vegetables first: A strategy to increase vegetable consumption in elementary school cafeterias. (United States)

    Elsbernd, S L; Reicks, M M; Mann, T L; Redden, J P; Mykerezi, E; Vickers, Z M


    Vegetable consumption in the United States is low despite the wealth of evidence that vegetables play an important role in reducing risk of various chronic diseases. Because eating patterns developed in childhood continue through adulthood, we need to form healthy eating habits in children. The objective of this study was to determine if offering vegetables before other meal components would increase the overall consumption of vegetables at school lunch. We served kindergarten through fifth-grade students a small portion (26-33 g) of a raw vegetable (red and yellow bell peppers) while they waited in line to receive the rest of their lunch meal. They then had the options to take more of the bell peppers, a different vegetable, or no vegetable from the lunch line. We measured the amount of each vegetable consumed by each child. Serving vegetables first greatly increased the number of students eating vegetables. On intervention days most of the vegetables consumed came from the vegetables-first portions. Total vegetable intake per student eating lunch was low because most students chose to not eat vegetables, but the intervention significantly increased this value. Serving vegetables first is a viable strategy to increase vegetable consumption in elementary schools. Long-term implementation of this strategy may have an important impact on healthy eating habits, vegetable consumption, and the health consequences of vegetable intake. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. River Corridors (Jan 2, 2015) (United States)

    Vermont Center for Geographic Information — River corridors are delineated to provide for the least erosive meandering and floodplain geometry toward which a river will evolve over time. River corridor maps...

  1. A Distribution Survey for Otters along a River in Central Bhutan


    Prakash Chettri; Melissa Savage


    We report the findings of a survey for otters along a major river in central Bhutan. The river bears various names in different stretches along its run, including Mochhu, Phochhu, Punatsangchhu and Sunkosh. We report: 1) the distribution and density of otter sign, including tracks, scats, latrines and dens, 2) the correlation between sign abundance and vegetation and substrate characteristics, and 3) the correlation of otter sign with human disturbance. Five of the six 5.5 km transects sample...

  2. Development and Interpretation of New Sediment Rating Curve Considering the Effect of Vegetation Cover for Asian Basins

    Directory of Open Access Journals (Sweden)

    Jie Wang


    Full Text Available Suspended sediment concentration of a river can provide very important perspective on erosion or soil loss of one river basin ecosystem. The changes of land use and land cover, such as deforestation or afforestation, affect sediment yield process of a catchment through changing the hydrological cycle of the area. A sediment rating curve can describe the average relation between discharge and suspended sediment concentration for a certain location. However, the sediment load of a river is likely to be undersimulated from water discharge using least squares regression of log-transformed variables and the sediment rating curve does not consider temporal changes of vegetation cover. The Normalized Difference Vegetation Index (NDVI can well be used to analyze the status of the vegetation cover well. Thus long time monthly NDVI data was used to detect vegetation change in the past 19 years in this study. Then monthly suspended sediment concentration and discharge from 1988 to 2006 in Laichau station were used to develop one new sediment rating curve and were validated in other Asian basins. The new sediment model can describe the relationship among sediment yield, streamflow, and vegetation cover, which can be the basis for soil conservation and sustainable ecosystem management.

  3. 2011 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    West, W. J.; Lucas, J. G.; Gano, K. A.


    This report documents the status of revegetation projects and natural resources mitigation efforts conducted for remediated waste sites and other activities associated with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 cleanup of National Priorities List waste sites at Hanford. This report contains the vegetation monitoring data that was collected in the spring and summer of 2011 from the River Corridor Closure Contractor’s revegetation and mitigation areas on the Hanford Site.

  4. 2010 River Corridor Closure Contractor Revegetation and Mitigation Monitoring Report

    Energy Technology Data Exchange (ETDEWEB)

    C. T. Lindsey, A. L. Johnson


    This report documents eh status of revegetation projects and natural resources mitigation efforts conducted for remediated waste sites and other activities associated with CERLA cleanup of National Priorities List waste sites at Hanford. This report contains vegetation monitoring data that were collected in the spring and summer of 2010 from the River Corridor Closure Contract’s revegetation and mitigation areas on the Hanford Site.

  5. Late Quaternary river channel migrations of the Kura River in Transcaucasia - tectonic versus climatic causes (United States)

    von Suchodoletz, Hans; Gärtner, Andreas; Hoth, Silvan; Umlauft, Josefine; Godoladze, Tea; Faust, Dominik


    Large-scale river channel migrations either in the form of avulsions or combing, i.e. progressive lateral migrations, are global phenomena during the Late Quaternary. Such channel migrations were triggered by tectonics, climate change, human activity or a combination of those factors. River channel migrations have the potential to cause significant human and economic losses. Thus, a more thorough knowledge about underlying causes and process rates is essential. Furthermore, such studies will elucidate the sensitivity or robustness of rivers to different external and internal forcing-agents, i.e. they help to identify the dominant drivers of regional landscape evolution. The Caucasus region is part of the active collision zone between the Africa-Arabian and the Eurasian plates, and is characterized by high current tectonic activity. Furthermore, significant environmental changes took place during the Late Quaternary, i.e. the shrinking or even disappearance of glaciers in the Greater and Lesser Caucasus or fundamental changes of the vegetation cover varying between woodland and grassland-dominated vegetation. The Kura River is the main gaining stream of the Transcaucasian Depression located between the Greater Caucasus Mountains in the north and the Lesser Caucasus Mountains in the south, and receives several tributaries from both mountain ranges. This study focusses on the middle course of the Kura River in eastern Georgia, SE of the city of Tbilisi. Integration of fluvial geomorphology, geochronology, heavy mineral analyses and seismo-tectonic analyses demonstrates that this part of the Kura River underwent large-scale channel migrations up to >10 km during Late Pleistocene and Holocene. It is interpreted that these movements followed both tectonic and climatic triggers: Whereas SW-ward migrations were caused by tectonic uplift in and SW-directed advance of the Kura fold and thrust belt as part of the Greater Caucasus, NE-ward migrations occurred during cold

  6. Colorado River basin sensitivity to disturbance impacts (United States)

    Bennett, K. E.; Urrego-Blanco, J. R.; Jonko, A. K.; Vano, J. A.; Newman, A. J.; Bohn, T. J.; Middleton, R. S.


    The Colorado River basin is an important river for the food-energy-water nexus in the United States and is projected to change under future scenarios of increased CO2emissions and warming. Streamflow estimates to consider climate impacts occurring as a result of this warming are often provided using modeling tools which rely on uncertain inputs—to fully understand impacts on streamflow sensitivity analysis can help determine how models respond under changing disturbances such as climate and vegetation. In this study, we conduct a global sensitivity analysis with a space-filling Latin Hypercube sampling of the model parameter space and statistical emulation of the Variable Infiltration Capacity (VIC) hydrologic model to relate changes in runoff, evapotranspiration, snow water equivalent and soil moisture to model parameters in VIC. Additionally, we examine sensitivities of basin-wide model simulations using an approach that incorporates changes in temperature, precipitation and vegetation to consider impact responses for snow-dominated headwater catchments, low elevation arid basins, and for the upper and lower river basins. We find that for the Colorado River basin, snow-dominated regions are more sensitive to uncertainties. New parameter sensitivities identified include runoff/evapotranspiration sensitivity to albedo, while changes in snow water equivalent are sensitive to canopy fraction and Leaf Area Index (LAI). Basin-wide streamflow sensitivities to precipitation, temperature and vegetation are variable seasonally and also between sub-basins; with the largest sensitivities for smaller, snow-driven headwater systems where forests are dense. For a major headwater basin, a 1ºC of warming equaled a 30% loss of forest cover, while a 10% precipitation loss equaled a 90% forest cover decline. Scenarios utilizing multiple disturbances led to unexpected results where changes could either magnify or diminish extremes, such as low and peak flows and streamflow timing

  7. Geomorphic status of regulated rivers in the Iberian Peninsula. (United States)

    Lobera, G; Besné, P; Vericat, D; López-Tarazón, J A; Tena, A; Aristi, I; Díez, J R; Ibisate, A; Larrañaga, A; Elosegi, A; Batalla, R J


    River regulation by dams modifies flow regimes, interrupts the transfer of sediment through channel networks, and alters downstream bed dynamics, altogether affecting channel form and processes. So far, most studies on the geomorphic impacts of dams are restricted to single rivers, or even single river stretches. In this paper we analyse the geomorphic status of 74 river sites distributed across four large basins in the Iberian Peninsula (i.e. 47 sites located downstream of dams). For this purpose, we combine field data with hydrological data available from water agencies, and analyse historical (1970) and current aerial photographs. In particular, we have developed a Geomorphic Status (GS) index that allows us to assess the physical structure of a given channel reach and its change through time. The GS encompasses a determination of changes in sedimentary units, sediment availability, bar stability and channel flow capacity. Sites are statistically grouped in four clusters based on contrasted physical and climate characteristics. Results emphasise that regulation changes river's flow regime with a generalized reduction of the magnitude and frequency of floods (thus flow competence). This, in addition to the decrease downstream sediment supply, results in the loss of active bars as they are encroached by vegetation, to the point that only reaches with little or no regulation maintain exposed sedimentary deposits. The GS of regulated river reaches is negatively correlated with magnitude of the impoundment (regulation). Heavily impacted reaches present channel stabilization and, in contrast to the hydrological response, the distance and number of tributaries do not reverse the geomorphic impact of the dams. Stabilization limits river dynamics and may contribute to the environmental degradation of the fluvial ecosystem. Overall, results describe the degree of geomorphological alteration experienced by representative Iberian rivers mostly because of regulation

  8. Preserving the Dnipro River

    International Development Research Centre (IDRC) Digital Library (Canada)

    Humanity inherited the true sense of proportion, synergy, and harmony from the natural environment. ..... In Ukraine, the middle and lower sections of the Dnipro have a drainage ... The following large cities are located in the Dnipro basin: in Russia, .... In Kherson Oblast and in river basins of some small rivers it is as high as ...

  9. River flooding and its impacts on large-scale biocontrol of Tamarix in the Colorado and Virgin River system: Moving targets and trajectories (United States)

    Along riparian corridors throughout the arid and semiarid regions of the western United States, non-native shrubs and trees in the genus Tamarix have replaced native vegetation. Plant communities along rivers with altered flow regimes and flood control have become particularly vulnerable to widespre...

  10. Influences of channelization on discharge of suspended sediment and wetland vegetation in Kushiro Marsh, northern Japan (United States)

    Nakamura, Futoshi; Sudo, Tadashi; Kameyama, Satoshi; Jitsu, Mieko


    The effects of wetlands on hydrology, water quality, and wildlife habitat are internationally recognized. Protecting the remaining wetlands is one of the most important environmental issues in many countries. However wetlands in Japan have been gradually shrinking due to agricultural development and urbanization, which generally lowers the groundwater level and introduces suspended sediment and sediment-associated nutrients into wetlands. We examined the influences of channelization on discharge of suspended sediment and wetland vegetation in Hokkaido, northern Japan. The impact of river channelization was confirmed not only by the sediment budgets but also by river aggradation or degradation after the channelization and by the resultant vegetational changes. The budgets of suspended sediment demonstrated that wash load was the predominant component accounting for 95% of the total suspended load delivered into the wetland. This suspended sediment was primarily transported into the wetland by flooding associated with heavy rainfall. Twenty-three percent of the wash load and 63% of the suspended bed material load were deposited in the channelized reach, which produced aggradation of about 2 m at the end of the reach. A shorting of the length of the channel, due to channelization of a meandering river, steepened the slope and enhanced the stream power to transport sediment. This steepening shifted the depositional zones of fine sediment 5 km downstream and aggraded the riverbed. Development of the watershed may increase not only the water discharge but also the amount of suspended sediments. The aggradation reduced the carrying capacity of the channel and caused sediment ladened water to flood over the wetlands. The fine sediment accumulated on the wetlands gradually altered the edaphic conditions and wetland vegetation. A low percentage (10 to 15%) of organic contents of wetlands' soil is more evidence indicating that the present condition is far different from

  11. Biologically active matters in soy vegetative mass




    Maintenance of row of bioactive matters of phenic nature in particular, isoflavonoids is investigational at to soy-bean cakes to vegetative mass of soy in the phases of vegetation of 8 the most widespread sorts of soy in Ukraine.

  12. Vegetation - San Felipe Valley [ds172 (United States)

    California Natural Resource Agency — This Vegetation Map of the San Felipe Valley Wildlife Area in San Diego County, California is based on vegetation samples collected in the field in 2002 and 2005 and...

  13. Biota - 2009 Vegetation Inventory - Lake Ashtabula, ND (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — 2009 Vegetation Classification for Lake Ashtabula, ND Vegetation Project Report, OMBIL Environmental Stewardship - Level 1 Inventory, U.S. Army Corps of Engineers...

  14. Ecosystems past: prehistory of California vegetation (United States)

    C.I. Millar; W.B. Woolfenden


    The history of California's vegetation, from origins in the Mesozoic through Quaternary is outlined. Climatic and geologic history and the processes driving changes in vegetation over time are also described. 

  15. Marketing African Leafy Vegetables: Challenges and Opportunities ...

    African Journals Online (AJOL)

    Marketing African Leafy Vegetables: Challenges and Opportunities in the Kenyan Context. ... The market share of ALVs vis-à-vis other vegetable species, particularly kales, cabbages and ... EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  16. Biota - 2011 Vegetation Inventory - Marsh Lake, MN (United States)

    Army Corps of Engineers, Department of the Army, Department of Defense — 2011 Vegetation Classification for Marsh Lake, MN Vegetation Project Report, OMBIL Environmental Stewardship - Level 1 Inventory. Marsh Lake is located on the...

  17. Vegetation coupling to global climate: Trajectories of vegetation change and phenology modeling from satellite observations (United States)

    Fisher, Jeremy Isaac

    Important systematic shifts in ecosystem function are often masked by natural variability. The rich legacy of over two decades of continuous satellite observations provides an important database for distinguishing climatological and anthropogenic ecosystem changes. Examples from semi-arid Sudanian West Africa and New England (USA) illustrate the response of vegetation to climate and land-use. In Burkina Faso, West Africa, pastoral and agricultural practices compete for land area, while degradation may follow intensification. The Nouhao Valley is a natural experiment in which pastoral and agricultural land uses were allocated separate, coherent reserves. Trajectories of annual net primary productivity were derived from 18 years of coarse-grain (AVHRR) satellite data. Trends suggested that pastoral lands had responded rigorously to increasing rainfall after the 1980's droughts. A detailed analysis at Landsat resolution (30m) indicated that the increased vegetative cover was concentrated in the river basins of the pastoral region, implying a riparian wood expansion. In comparison, riparian cover was reduced in agricultural regions. We suggest that broad-scale patterns of increasing semi-arid West African greenness may be indicative of climate variability, whereas local losses may be anthropogenic in nature. The contiguous deciduous forests, ocean proximity, topography, and dense urban developments of New England provide an ideal landscape to examine influences of climate variability and the impact of urban development vegetation response. Spatial and temporal patterns of interannual climate variability were examined via green leaf phenology. Phenology, or seasonal growth and senescence, is driven by deficits of light, temperature, and water. In temperate environments, phenology variability is driven by interannual temperature and precipitation shifts. Average and interannual phenology analyses across southern New England were conducted at resolutions of 30m (Landsat


    Directory of Open Access Journals (Sweden)

    V. G. Konovalov


    Full Text Available Rivers with snow-glacier alimentation in six basins of the Northern Caucasus (Cherek, Chegem, Baksan, Malka, Teberda, and upper course of the Terek River and Altai (the Katun’ River were investigated in 1946–2005 for the purpose to analyze long-term streamflow variations. It was noted that in 1976–2005 volume of annual runoff increased relative to the previous 30-year interval in four of six rivers of the Northern Caucasus. During the vegetation period the volume of runoff changed synchronously with the annual one. As for the river Katun’, its volumes and variability of both, the annual runoff and that for the vegetation season, decreased. In the course of investigation of spatial-temporal dynamics of hydrological and glaciological characteristics in the above river basins of the Northern Caucasus and the same of Katun’ River the following problems were considered and solved: a the information and methodological basis for regional calculations of the runoff for the rivers with snow-glacier alimentation had been improved and corrected; b changes of the components of hydrological cycle (precipitation, evaporation, and glacier runoff over the glaciation area had been estimated for the period of 1946–2005; c data on quality of the initial glaciological and hydrological information were integrated; d definitions of the runoff were verified by means of comparison of measured runoff with similar values calculated by equation of the annual water budget as a whole for the basin. It should be noted that the total areas of glaciers and areas of their ablation were significantly reduced, but areas and thicknesses of ice under the moraine cover increased. Despite widespread, sometimes twofold decrease in the relative part of glacier alimentation in the total river streamflow for period of April–September this did make almost no effect on the water supply of the vegetation period in individual basins as well as in the whole the Northern

  19. Remote sensing of wetlands at the Savannah River Plant

    International Nuclear Information System (INIS)

    Christensen, E.J.; Jensen, J.R.; Sharitz, R.R.


    The Savannah River Plant (SRP) occupies about 300 sq mi along a 10-mile stretch of the Savannah River. Large areas of wetlands cover the site, especially along tributary stream floodplains and the Savannah River. Some of these areas have been altered by cooling water discharges from nuclear production reactors onsite. To assess the effects of current and future plant operations on SRP and regional wetlands, an accurate quantitative survey was needed. Several studies were initiated to provide wetland acreage and distribution information: regional wetland inventories were provided from an analysis of LANDSAT multispectral scanner (MSS) satellite data. Wetlands were mapped throughout the entire Savannah River watershed and in the Savannah River floodplain. SRP wetlands were identified using a combination of LANDSAT MSS and Thematic Mapper satellite data and aerial photography. Wetlands in the SRP Savannah River swamp and thermally affected areas were mapped using high resolution MSS data collected from a low-flying aircraft. Vegetation communities in areas receiving cooling water discharges were then compared to surface temperatures measured from the airborne scanner at the same time to evaluate plant temperature tolerance. Historic changes to SRP wetlands from cooling water discharges were tabulated using aerial photography

  20. Irradiation of fruit and vegetables

    International Nuclear Information System (INIS)

    O'Beirne, David


    There is likely to be less economic incentive to irradiate fruits and vegetables compared with applications which increase the safety of foods such as elimination of Salmonella or decontamination of food ingredients. Of the fruit and vegetable applications, irradiation of mushrooms may offer the clearest economic benefits in North-Western Europe. The least likely application appears to be sprout inhibition in potatoes and onions, because of the greater efficiency and flexibility of chemical sprout inhibitors. In the longer-term, combinations between irradiation/MAP/other technologies will probably be important. Research in this area is at an early stage. Consumer attitudes to food irradiation remain uncertain. This will be a crucial factor in the commercial application of the technology and in the determining the balance between utilisation of irradiation and of technologies which compete with irradiation. (author)

  1. Hyperspectral remote sensing of vegetation (United States)

    Thenkabail, Prasad S.; Lyon, John G.; Huete, Alfredo


    Hyperspectral narrow-band (or imaging spectroscopy) spectral data are fast emerging as practical solutions in modeling and mapping vegetation. Recent research has demonstrated the advances in and merit of hyperspectral data in a range of applications including quantifying agricultural crops, modeling forest canopy biochemical properties, detecting crop stress and disease, mapping leaf chlorophyll content as it influences crop production, identifying plants affected by contaminants such as arsenic, demonstrating sensitivity to plant nitrogen content, classifying vegetation species and type, characterizing wetlands, and mapping invasive species. The need for significant improvements in quantifying, modeling, and mapping plant chemical, physical, and water properties is more critical than ever before to reduce uncertainties in our understanding of the Earth and to better sustain it. There is also a need for a synthesis of the vast knowledge spread throughout the literature from more than 40 years of research.

  2. Phenolic Compounds in Brassica Vegetables

    Directory of Open Access Journals (Sweden)

    Pablo Velasco


    Full Text Available Phenolic compounds are a large group of phytochemicals widespread in the plant kingdom. Depending on their structure they can be classified into simple phenols, phenolic acids, hydroxycinnamic acid derivatives and flavonoids. Phenolic compounds have received considerable attention for being potentially protective factors against cancer and heart diseases, in part because of their potent antioxidative properties and their ubiquity in a wide range of commonly consumed foods of plant origin. The Brassicaceae family includes a wide range of horticultural crops, some of them with economic significance and extensively used in the diet throughout the world. The phenolic composition of Brassica vegetables has been recently investigated and, nowadays, the profile of different Brassica species is well established. Here, we review the significance of phenolic compounds as a source of beneficial compounds for human health and the influence of environmental conditions and processing mechanisms on the phenolic composition of Brassica vegetables.

  3. Clearing and vegetation management issues

    International Nuclear Information System (INIS)



    Clearing and continued management of incompatible plant species is critical to maintaining safe and reliable transmission and distribution lines at British Columbia Hydro. As part of a general review of policies regarding rights-of-way, the clearing of BC Hydro rights-of-way was studied by a task team in order to formulate a set of recommended policies and procedures to guide employees in all rights-of-way decisions, and to provide clear direction for resolution of all rights-of-way issues in a cost-effective manner. Issues reviewed were: clearing standards and line security standardization for transmission circuits; clearing rights for removal of trees or management of vegetation beyond the statutory right-of-way; clearing and vegetation management procedures; tree replacement; arboricultural techniques; periodic reviewing of clearing practices; compensation for tree removal; herbicide use; and heritage and wildlife trees. Justification for the recommendation is provided along with alternate options and costs of compliance

  4. The vegetation and floristics of the Nkhuhlu Exclosures, Kruger National Park

    Directory of Open Access Journals (Sweden)

    Frances Siebert


    Full Text Available The need to conduct research on the impact of elephant on the environment prompted the construction of exclosures along two of the most important rivers in the Kruger National Park. Scientific research on these exclosures along the Sabie and Letaba rivers addresses how patterns of spatial and temporal heterogeneity of the riparian zone are affected by fire, flood and herbivory. To further assist this research programme, a vegetation survey was conducted at the Nkhuhlu exclosure site along the Sabie River to classify and map the vegetation of the area. This will provide baseline data to assess future changes in vegetation and floristic patterns due to small-scale environmental factors created by the presence/absence of herbivory and fire. Phytosociological data were analysed to identify plant communities and subsequent mapping units. Five plant communities, ten sub-communities and four variants were recognised and described in relation to prevailing soil forms. Differences in species richness, diversity and community structure of the plant communities are clearly articulated.

  5. Abiotic features of a river from the Upper Tietê River Basin (SP, Brazil along an environmental gradient

    Directory of Open Access Journals (Sweden)

    Katharina Eichbaum Esteves


    Full Text Available Aim: This study aimed to assess the spatial and seasonal variation of the water quality and physical habitat characteristics along the upper-middle stretch of the Paraitinga River, a tributary of Tietê River, considering the potential influence of different riparian conditions along the stretch studied.MethodsSixteen sites with different riparian vegetation, including native forest, secondary forest, pasture, and eucalyptus were sampled during the dry and rainy seasons of 2004/2005, before the damming of the Paraitinga Reservoir. Several physicochemical and habitat parameters were determined and data analyzed in relation to spatial distribution and potential influence of riparian conditions.ResultsWater quality parameters were in general within the limits established by CONAMA for Class 2 waters, except for turbidity and total phosphorus. There were seasonal and spatial differences in the limnological parameters along the stretch studied and apparently they were related to point specific influences associated with land use and canopy cover. Habitat characteristics were markedly different between the upper and middle river stretches, especially in relation to depth, width, substrate and canopy cover.ConclusionsAlthough a direct influence on the observed variables could not be attributed solely to the riparian vegetation, vegetation cover seemed to affect particular stream characteristics. Open pasture and eucalyptus sites were subject to point specific effects that caused phosphorus inputs and higher turbidity and temperature, and showed different morphological features, suggesting that land use at the sub-watershed scale was an important factor affecting stream conditions.

  6. Waste vegetable oil survey report

    Energy Technology Data Exchange (ETDEWEB)

    MacLeod, R. [Science enterprise Algoma seA, Sault Ste. Marie, ON (Canada)


    This study was conducted to estimate potential sources of feedstock waste oils for biodiesel production in the Sault Ste. Marie region of Ontario. Two feedstocks were investigated over a period of several months, notably cooking oil and waste vegetable oil. The study was conducted to examine oil throughput, collection practices, and to gauge interest in local initiatives. A distribution list of commercial restaurant listings was developed, and surveys were conducted with members of private enterprises, city government, and non-profit stakeholders in the region. Average volumes of waste vegetable oil were presented for different types of restaurants. The various types of oil used in the restaurants were also quantified. Results of the study showed a positive public response to the idea of a local biodiesel initiative. Steak house, fast food, and Italian establishments generated the largest portion of waste vegetable oil amongst survey respondents. However, the highest response rates came from establishments with little or no oil consumption. Many franchise fast food restaurants are already in contracts with waste oil removal companies. 3 tabs., 3 figs.

  7. Numerical modelling of river processes: flow and river bed deformation

    NARCIS (Netherlands)

    Tassi, P.A.


    The morphology of alluvial river channels is a consequence of complex interaction among a number of constituent physical processes, such as flow, sediment transport and river bed deformation. This is, an alluvial river channel is formed from its own sediment. From time to time, alluvial river

  8. Abandoned floodplain plant communities along a regulated dryland river (United States)

    Reynolds, L. V.; Shafroth, Patrick B.; House, P. K.


    Rivers and their floodplains worldwide have changed dramatically over the last century because of regulation by dams, flow diversions and channel stabilization. Floodplains no longer inundated by river flows following dam-induced flood reduction comprise large areas of bottomland habitat, but the effects of abandonment on plant communities are not well understood. Using a hydraulic flow model, geomorphic mapping and field surveys, we addressed the following questions along the Bill Williams River, Arizona: (i) What per cent of the bottomland do abandoned floodplains comprise? and (ii) Are abandoned floodplains quantitatively different from adjacent xeric and riparian surfaces in terms of vegetation composition and surface sediment? We found that nearly 70% of active channel and floodplain area was abandoned following dam installation. Abandoned floodplains along the Bill Williams River tend to be similar to each other yet distinct from neighbouring habitats: they have been altered physically from their historic state, leading to distinct combinations of surface sediments, hydrology and plant communities. Abandoned floodplains may transition to xeric communities over time but are likely to retain some riparian qualities as long as there is access to relatively shallow ground water. With expected increases in water demand and drying climatic conditions in many regions, these surfaces and associated vegetation will continue to be extensive in riparian landscapes worldwide

  9. Ecosystem Services and Related Sustainable Management of River Oases along the Tarim River in Northwest China (United States)

    Disse, M.; Keilholz, P.; Rumbaur, C.; Thevs, N.


    Within the Taklimakan Desert of Northwestern China, an area renowned for its extreme climate and vulnerable ecosystems, lies one of the largest inland rivers in the world, the Tarim River. Because the Tarim River is located in a remote area from the oceans, rainfall is extremely rare (less than 50 mm per year) but potential evaporation is high (3000 mm). Thus, the major source of water discharge comes from snowmelt and glacier-melt in the mountains. Though the water discharge into the Tarim River has experienced an increase over the past ten years, global climate change forecasts predict this water supply to decline within the century. The Tarim River is the major source of water in Northwestern China, and has become the hub of many economic activities related to agriculture and urban life. Over the past 50 years increased activity in the area has led to a severe decline in river flow. Both human and natural ecosystems have been impacted by water diversions. Since rainfall is rare, the majority of vegetation in this area depends solely on groundwater for survival, and plants are experiencing stress caused by decreasing groundwater levels. Recently nearby cities have experienced severe dust storms caused by the shrinking of the vegetative region along the river. SuMaRiO (Sustainable Management of River Oases) is a bundle project between Germany and China working to contribute to a sustainable land management which explicitly takes into account ecosystem functions (ESF) and ecosystem services (ESS). In a transdisciplinary research process, SuMaRiO will identify realizable management strategies, considering social, economic and ecological criteria. SuMaRiO is developing tools to work with Chinese decision makers to implement sustainable land management strategies. In addition, research is being conducted to estimate climate change impacts, floodplain biodiversity, and water runoff characteristics. The overarching goal of SuMaRiO is to support oasis management along

  10. State-and-transition prototype model of riparian vegetation downstream of Glen Canyon Dam, Arizona (United States)

    Ralston, Barbara E.; Starfield, Anthony M.; Black, Ronald S.; Van Lonkhuyzen, Robert A.


    Facing an altered riparian plant community dominated by nonnative species, resource managers are increasingly interested in understanding how to manage and promote healthy riparian habitats in which native species dominate. For regulated rivers, managing flows is one tool resource managers consider to achieve these goals. Among many factors that can influence riparian community composition, hydrology is a primary forcing variable. Frame-based models, used successfully in grassland systems, provide an opportunity for stakeholders concerned with riparian systems to evaluate potential riparian vegetation responses to alternative flows. Frame-based, state-and-transition models of riparian vegetation for reattachment bars, separation bars, and the channel margin found on the Colorado River downstream of Glen Canyon Dam were constructed using information from the literature. Frame-based models can be simple spreadsheet models (created in Microsoft® Excel) or developed further with programming languages (for example, C-sharp). The models described here include seven community states and five dam operations that cause transitions between states. Each model divides operations into growing (April–September) and non-growing seasons (October–March) and incorporates upper and lower bar models, using stage elevation as a division. The inputs (operations) can be used by stakeholders to evaluate flows that may promote dynamic riparian vegetation states, or identify those flow options that may promote less desirable states (for example, Tamarisk [Tamarix sp.] temporarily flooded shrubland). This prototype model, although simple, can still elicit discussion about operational options and vegetation response.

  11. [Estimation of desert vegetation coverage based on multi-source remote sensing data]. (United States)

    Wan, Hong-Mei; Li, Xia; Dong, Dao-Rui


    Taking the lower reaches of Tarim River in Xinjiang of Northwest China as study areaAbstract: Taking the lower reaches of Tarim River in Xinjiang of Northwest China as study area and based on the ground investigation and the multi-source remote sensing data of different resolutions, the estimation models for desert vegetation coverage were built, with the precisions of different estimation methods and models compared. The results showed that with the increasing spatial resolution of remote sensing data, the precisions of the estimation models increased. The estimation precision of the models based on the high, middle-high, and middle-low resolution remote sensing data was 89.5%, 87.0%, and 84.56%, respectively, and the precisions of the remote sensing models were higher than that of vegetation index method. This study revealed the change patterns of the estimation precision of desert vegetation coverage based on different spatial resolution remote sensing data, and realized the quantitative conversion of the parameters and scales among the high, middle, and low spatial resolution remote sensing data of desert vegetation coverage, which would provide direct evidence for establishing and implementing comprehensive remote sensing monitoring scheme for the ecological restoration in the study area.

  12. The Impact of Vegetative Slope on Water Flow and Pollutant Transport through Embankments

    Directory of Open Access Journals (Sweden)

    Liting Sheng


    Full Text Available Embankments are common structures along rivers or lakes in riparian zones in plain areas. They should have natural slopes instead of slopes covered by concrete or other hard materials, in order to rebuild sustainable ecosystems for riparian zones. This study was conducted to evaluate the effects of vegetative slopes on water flow and pollutant transport through the embankments. Three embankments with different slope treatments (a bare slope, a slope covered in centipede grass, a slope covered in tall fescue were examined, and three inflow applications of pollute water with different concentration of total nitrogen (TN and total phosphorus (TP used to simulate different agricultural non-point pollution levels. The results showed that the water flux rates of the three embankments were relatively stable under all inflow events, and almost all values were higher than 80%. The embankments with vegetative slopes had better nitrogen removal than the bare slope under all events, and the one with tall fescue slope was best, but the benefits of vegetative slopes decreased with increasing inflow concentration. Moreover, there were no significant differences between the embankments on phosphorus removal, for which the reductions were all high (above 90% with most loads remaining in the front third of embankment bodies. Overall, the embankments with vegetative slopes had positive effects on water exchange and reducing non-point pollutant into lake or river water, which provides a quantitative scientific basis for the actual layout of lakeshores.

  13. Uranium in river water

    International Nuclear Information System (INIS)

    Palmer, M.R.; Edmond, J.M.


    The concentration of dissolved uranium has been determined in over 250 river waters from the Orinoco, Amazon, and Ganges basins. Uranium concentrations are largely determined by dissolution of limestones, although weathering of black shales represents an important additional source in some basins. In shield terrains the level of dissolved U is transport limited. Data from the Amazon indicate that floodplains do not represent a significant source of U in river waters. In addition, the authors have determined dissolved U levels in forty rivers from around the world and coupled these data with previous measurements to obtain an estimate for the global flux of dissolved U to the oceans. The average concentration of U in river waters is 1.3 nmol/kg, but this value is biased by very high levels observed in the Ganges-Brahmaputra and Yellow rivers. When these river systems are excluded from the budget, the global average falls to 0.78 nmol/kg. The global riverine U flux lies in the range of 3-6 x 10 7 mol/yr. The major uncertainty that restricts the accuracy of this estimate (and that of all other dissolved riverine fluxes) is the difficulty in obtaining representative samples from rivers which show large seasonal and annual variations in runoff and dissolved load

  14. Performance Evaluation and Field Application of Porous Vegetation Concrete Made with By-Product Materials for Ecological Restoration Projects

    Directory of Open Access Journals (Sweden)

    Hwang-Hee Kim


    Full Text Available The purpose of this study was to evaluate the performance of porous vegetation concrete block made from blast furnace slag cement containing industrial by-products such as blast furnace slag aggregate and powder. The blocks were tested for void ratio, compressive strength and freeze-thaw resistance to determine the optimal mixing ratio for the porous vegetation block. An economic analysis of the mixing ratio showed that the economic efficiency increased when blast furnace slag aggregate and cement were used. Porous vegetation concrete blocks for river applications were designed and produced. Hydraulic safety, heavy metal elution and vegetation tests were completed after the blocks were applied in the field. The measured tractive force ranged between 7.0 kg/m2 for fascine revetment (vegetation revetment and 16.0 kg/m2 for stone pitching (hard revetment, which ensured sufficient hydraulic stability in the field. Plant growth was measured after the porous vegetation concrete block was placed in the field. Seeds began to sprout one week after seeding; after six weeks, the plant length exceeded 300 mm. The average coverage ratio reached as high as 90% after six weeks of vegetation. These results clearly indicated that the porous vegetation concrete block was suitable for environmental restoration projects.

  15. Amazon River carbon dioxide outgassing fuelled by wetlands. (United States)

    Abril, Gwenaël; Martinez, Jean-Michel; Artigas, L Felipe; Moreira-Turcq, Patricia; Benedetti, Marc F; Vidal, Luciana; Meziane, Tarik; Kim, Jung-Hyun; Bernardes, Marcelo C; Savoye, Nicolas; Deborde, Jonathan; Souza, Edivaldo Lima; Albéric, Patrick; Landim de Souza, Marcelo F; Roland, Fabio


    River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle. A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial ecosystems. It is generally assumed that inland waters emit carbon that has been previously fixed upstream by land plant photosynthesis, then transferred to soils, and subsequently transported downstream in run-off. But at the scale of entire drainage basins, the lateral carbon fluxes carried by small rivers upstream do not account for all of the CO2 emitted from inundated areas downstream. Three-quarters of the world's flooded land consists of temporary wetlands, but the contribution of these productive ecosystems to the inland water carbon budget has been largely overlooked. Here we show that wetlands pump large amounts of atmospheric CO2 into river waters in the floodplains of the central Amazon. Flooded forests and floating vegetation export large amounts of carbon to river waters and the dissolved CO2 can be transported dozens to hundreds of kilometres downstream before being emitted. We estimate that Amazonian wetlands export half of their gross primary production to river waters as dissolved CO2 and organic carbon, compared with only a few per cent of gross primary production exported in upland (not flooded) ecosystems. Moreover, we suggest that wetland carbon export is potentially large enough to account for at least the 0.21 petagrams of carbon emitted per year as CO2 from the central Amazon River and its floodplains. Global carbon budgets should explicitly address temporary or vegetated flooded areas, because these ecosystems combine high aerial primary production with large, fast carbon export, potentially supporting a substantial fraction of CO2 evasion from inland waters.

  16. River, delta and coastal morphological response accounting for biological dynamics

    Directory of Open Access Journals (Sweden)

    W. Goldsmith


    Full Text Available Management and construction can increase resilience in the face of climate change, and benefits can be enhanced through integration of biogenic materials including shells and vegetation. Rivers and coastal landforms are dynamic systems that respond to intentional and unintended manipulation of critical factors, often with unforeseen and/or undesirable resulting effects. River management strategies have impacts that include deltas and coastal areas which are increasingly vulnerable to climate change with reference to sea level rise and storm intensity. Whereas conventional assessment and analysis of rivers and coasts has relied on modelling of hydrology, hydraulics and sediment transport, incorporating additional biological factors can offer more comprehensive, beneficial and realistic alternatives. Suitable modelling tools can provide improved decision support. The question has been whether current models can effectively address biological responses with suitable reliability and efficiency. Since morphodynamic evolution exhibits its effects on a large timescale, the choice of mathematical model is not trivial and depends upon the availability of data, as well as the spatial extent, timelines and computation effort desired. The ultimate goal of the work is to set up a conveniently simplified river morphodynamic model, coupled with a biological dynamics plant population model able to predict the long-term evolution of large alluvial river systems managed through bioengineering. This paper presents the first step of the work related to the application of the model accounting for stationary vegetation condition. Sensitivity analysis has been performed on the main hydraulic, sedimentology, and biological parameters. The model has been applied to significant river training in Europe, Asia and North America, and comparative analysis has been used to validate analytical solutions. Data gaps and further areas for investigation are identified.

  17. River, delta and coastal morphological response accounting for biological dynamics (United States)

    Goldsmith, W.; Bernardi, D.; Schippa, L.


    Management and construction can increase resilience in the face of climate change, and benefits can be enhanced through integration of biogenic materials including shells and vegetation. Rivers and coastal landforms are dynamic systems that respond to intentional and unintended manipulation of critical factors, often with unforeseen and/or undesirable resulting effects. River management strategies have impacts that include deltas and coastal areas which are increasingly vulnerable to climate change with reference to sea level rise and storm intensity. Whereas conventional assessment and analysis of rivers and coasts has relied on modelling of hydrology, hydraulics and sediment transport, incorporating additional biological factors can offer more comprehensive, beneficial and realistic alternatives. Suitable modelling tools can provide improved decision support. The question has been whether current models can effectively address biological responses with suitable reliability and efficiency. Since morphodynamic evolution exhibits its effects on a large timescale, the choice of mathematical model is not trivial and depends upon the availability of data, as well as the spatial extent, timelines and computation effort desired. The ultimate goal of the work is to set up a conveniently simplified river morphodynamic model, coupled with a biological dynamics plant population model able to predict the long-term evolution of large alluvial river systems managed through bioengineering. This paper presents the first step of the work related to the application of the model accounting for stationary vegetation condition. Sensitivity analysis has been performed on the main hydraulic, sedimentology, and biological parameters. The model has been applied to significant river training in Europe, Asia and North America, and comparative analysis has been used to validate analytical solutions. Data gaps and further areas for investigation are identified.

  18. Savannah River Plant environment

    International Nuclear Information System (INIS)

    Dukes, E.K.


    On June 20, 1972, the Atomic Energy Commission designated 192,323 acres of land near Aiken, SC, as the nation's first National Environmental Research Park. The designated land surrounds the Department of Energy's Savannah River Plant production complex. The site, which borders the Savannah River for 17 miles, includes swampland, pine forests, abandoned town sites, a large man-made lake for cooling water impoundment, fields, streams, and watersheds. This report is a description of the geological, hydrological, meteorological, and biological characteristics of the Savannah River Plant site and is intended as a source of information for those interested in environmental research at the site. 165 references, 68 figures, 52 tables

  19. Health Benefits of Fruits and Vegetables1 (United States)

    Slavin, Joanne L.; Lloyd, Beate


    Fruits and vegetables are universally promoted as healthy. The Dietary Guidelines for Americans 2010 recommend you make one-half of your plate fruits and vegetables. also supports that one-half the plate should be fruits and vegetables. Fruits and vegetables include a diverse group of plant foods that vary greatly in content of energy and nutrients. Additionally, fruits and vegetables supply dietary fiber, and fiber intake is linked to lower incidence of cardiovascular disease and obesity. Fruits and vegetables also supply vitamins and minerals to the diet and are sources of phytochemicals that function as antioxidants, phytoestrogens, and antiinflammatory agents and through other protective mechanisms. In this review, we describe the existing dietary guidance on intake of fruits and vegetables. We also review attempts to characterize fruits and vegetables into groups based on similar chemical structures and functions. Differences among fruits and vegetables in nutrient composition are detailed. We summarize the epidemiological and clinical studies on the health benefits of fruits and vegetables. Finally, we discuss the role of fiber in fruits and vegetables in disease prevention. PMID:22797986

  20. Case study on rehabilitation of a polluted urban water body in Yangtze River Basin. (United States)

    Wu, Juan; Cheng, Shuiping; Li, Zhu; Guo, Weijie; Zhong, Fei; Yin, Daqiang


    In the past three decades, the fast development of economy and urbanization has caused increasingly severe pollutions of urban water bodies in China. Consequently, eutrophication and deterioration of aquatic ecosystem, which is especially significant for aquatic vegetation, inevitably became a pervasive problem across the Yangtze River Basin. To rehabilitate the degraded urban water bodies, vegetation replanting is an important issue to improve water quality and to rehabilitate ecosystem. As a case study, a representative polluted urban river, Nanfeihe River, in Hefei City, Anhui Province, was chosen to be a rehabilitation target. In October 2009 and May 2010, 13 species of indigenous and prevalent macrophytes, including seven species emergent, one species floating leaved, and five species submersed macrophytes, were planted along the bank slopes and in the river. Through 1.5 years' replanting practice, the water quality and biodiversity of the river had been improved. The concentrations of total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH4 (+)-N) declined by 46.0, 39.5, and 60.4 %, respectively. The species of macrophytes increased from 14 to 60, and the biodiversity of phytoplankton rose significantly in the river (purban waters restoration in the middle-downstream area of Yangtze River Base.

  1. Microbiological Spoilage of Fruits and Vegetables (United States)

    Barth, Margaret; Hankinson, Thomas R.; Zhuang, Hong; Breidt, Frederick

    Consumption of fruit and vegetable products has dramatically increased in the United States by more than 30% during the past few decades. It is also estimated that about 20% of all fruits and vegetables produced is lost each year due to spoilage. The focus of this chapter is to provide a general background on microbiological spoilage of fruit and vegetable products that are organized in three categories: fresh whole fruits and vegetables, fresh-cut fruits and vegetables, and fermented or acidified vegetable products. This chapter will address characteristics of spoilage microorganisms associated with each of these fruit and vegetable categories including spoilage mechanisms, spoilage defects, prevention and control of spoilage, and methods for detecting spoilage microorganisms.

  2. Estimating vegetation dryness to optimize fire risk assessment with spot vegetation satellite data in savanna ecosystems (United States)

    Verbesselt, J.; Somers, B.; Lhermitte, S.; van Aardt, J.; Jonckheere, I.; Coppin, P.


    The lack of information on vegetation dryness prior to the use of fire as a management tool often leads to a significant deterioration of the savanna ecosystem. This paper therefore evaluated the capacity of SPOT VEGETATION time-series to monitor the vegetation dryness (i.e., vegetation moisture content per vegetation amount) in order to optimize fire risk assessment in the savanna ecosystem of Kruger National Park in South Africa. The integrated Relative Vegetation Index approach (iRVI) to quantify the amount of herbaceous biomass at the end of the rain season and the Accumulated Relative Normalized Difference vegetation index decrement (ARND) related to vegetation moisture content were selected. The iRVI and ARND related to vegetation amount and moisture content, respectively, were combined in order to monitor vegetation dryness and optimize fire risk assessment in the savanna ecosystems. In situ fire activity data was used to evaluate the significance of the iRVI and ARND to monitor vegetation dryness for fire risk assessment. Results from the binary logistic regression analysis confirmed that the assessment of fire risk was optimized by integration of both the vegetation quantity (iRVI) and vegetation moisture content (ARND) as statistically significant explanatory variables. Consequently, the integrated use of both iRVI and ARND to monitor vegetation dryness provides a more suitable tool for fire management and suppression compared to other traditional satellite-based fire risk assessment methods, only related to vegetation moisture content.

  3. Morphodynamic modeling of the river pattern continuum (Invited) (United States)

    Nicholas, A. P.


    Numerical models provide valuable tools for integrating understanding of fluvial processes and morphology. Moreover, they have considerable potential for use in investigating river responses to environmental change and catchment management, and for aiding the interpretation of alluvial deposits and landforms. For this potential to be realised fully, such models must be capable of representing diverse river styles and the spatial and temporal transitions between styles that are driven by changes in environmental forcing. However, while numerical modeling of rivers has advanced considerable over the past few decades, this has been accomplished largely by developing separate approaches to modeling single and multi-thread channels. Results are presented here from numerical simulations undertaken using a new model of river and floodplain co-evolution, applied to investigate the morphodynamics of large sand-bed rivers. This model solves the two-dimensional depth-averaged shallow water equations using a Godunov-type finite volume scheme, with a two-fraction representation of sediment transport, and includes the effects of secondary circulation, bank erosion and floodplain development due to the colonization of bar surfaces by vegetation. Simulation results demonstrate the feasibility of representing a wide range of fluvial styles (including braiding, meandering and anabranching channels) using relatively simple physics-based models, and provide insight into the controls on channel pattern diversity in large sand-bed rivers. Analysis of model sensitivity illustrates the important role of upstream boundary conditions as a control on channel dynamics. Moreover, this analysis highlights key uncertainties in model process representation and their implications for modelling river evolution in response to natural and anthropogenic-induced river disturbance.

  4. Vegetated Riprap Installation Techniques for Steambank Protection, Fish and Wildlife Habitat Creation (United States)

    Raymond, Pierre


    the past seven years to the stream banks of eleven different sites on large and medium sized rivers in three Provinces of Canada. To date, the survival and growth of vegetated riprap brush layers installed along riverbanks has been assessed as good to excellent, resulting in the substantial creation of fish, wildlife and urban habitat. The survival and growth, along with early results of an excavation trial, will be presented.

  5. Estimating Vegetation Rainfall Interception Using Remote Sensing Observations at Very High Resolution (United States)

    Cui, Y.; Zhao, P.; Hong, Y.; Fan, W.; Yan, B.; Xie, H.


    Abstract: As an important compont of evapotranspiration, vegetation rainfall interception is the proportion of gross rainfall that is intercepted, stored and subsequently evaporated from all parts of vegetation during or following rainfall. Accurately quantifying the vegetation rainfall interception at a high resolution is critical for rainfall-runoff modeling and flood forecasting, and is also essential for understanding its further impact on local, regional, and even global water cycle dynamics. In this study, the Remote Sensing-based Gash model (RS-Gash model) is developed based on a modified Gash model for interception loss estimation using remote sensing observations at the regional scale, and has been applied and validated in the upper reach of the Heihe River Basin of China for different types of vegetation. To eliminate the scale error and the effect of mixed pixels, the RS-Gash model is applied at a fine scale of 30 m with the high resolution vegetation area index retrieved by using the unified model of bidirectional reflectance distribution function (BRDF-U) for the vegetation canopy. Field validation shows that the RMSE and R2 of the interception ratio are 3.7% and 0.9, respectively, indicating the model's strong stability and reliability at fine scale. The temporal variation of vegetation rainfall interception loss and its relationship with precipitation are further investigated. In summary, the RS-Gash model has demonstrated its effectiveness and reliability in estimating vegetation rainfall interception. When compared to the coarse resolution results, the application of this model at 30-m fine resolution is necessary to resolve the scaling issues as shown in this study. Keywords: rainfall interception; remote sensing; RS-Gash analytical model; high resolution

  6. Hunting camp. River Murray


    ? Bayliss, Charles, 1850-1897, photographer


    200 x 149 mm. A good photograph showing a group of aborigines (in European clothes) with two hunting dogs, holding spears and standing in front of rough wooden cabins; with the river in the background. Photograph unknown, possible Charles Bayliss.

  7. Wild and Scenic Rivers (United States)

    Earth Data Analysis Center, University of New Mexico — This map layer portrays the linear federally-owned land features (i.e., national parkways, wild and scenic rivers, etc.) of the United States, Puerto Rico, and the...

  8. Synthesis of Upper Verde River research and monitoring 1993-2008 (United States)

    Daniel G. Neary; Alvin L. Medina; John N. Rinne


    This volume is a state-of-knowledge synthesis of monitoring and research conducted on the Upper Verde River (UVR) of Arizona. It contains information on the history, hydrology, soils, geomorphology, vegetation, and fish fauna of the area that can help land managers and other scientists in successfully conducting ecosystem management and future monitoring and research...

  9. River response to variations of periglacial climate in mid-latitude Europe.

    NARCIS (Netherlands)

    Mol, J.; Vandenberghe, J.; Kasse, C.


    The Last Glaciation was characterised by considerable changes in climate. Many European river basins reacted to these changes by initial incision and subsequent pattern change. Earlier research explained this by the time lag of vegetation development after a climatic change, which considerably

  10. Perspectives in using a remotely sensed dryness index in distributed hydrological models at river basin scale

    DEFF Research Database (Denmark)

    Andersen, Jens Asger; Sandholt, Inge; Jensen, Karsten Høgh


    In a previous study a spatially distributed hydrological model, based on the MIKE SHE code, was constructed and validated for the 375 000 km2 Senegal River basin in West Africa. The model was constructed using spatial data on topography, soil types and vegetation characteristics together with time...

  11. Vegetation fire proneness in Europe (United States)

    Pereira, Mário; Aranha, José; Amraoui, Malik


    Fire selectivity has been studied for vegetation classes in terms of fire frequency and fire size in a few European regions. This analysis is often performed along with other landscape variables such as topography, distance to roads and towns. These studies aims to assess the landscape sensitivity to forest fires in peri-urban areas and land cover changes, to define landscape management guidelines and policies based on the relationships between landscape and fires in the Mediterranean region. Therefore, the objectives of this study includes the: (i) analysis of the spatial and temporal variability statistics within Europe; and, (ii) the identification and characterization of the vegetated land cover classes affected by fires; and, (iii) to propose a fire proneness index. The datasets used in the present study comprises: Corine Land Cover (CLC) maps for 2000 and 2006 (CLC2000, CLC2006) and burned area (BA) perimeters, from 2000 to 2013 in Europe, provided by the European Forest Fire Information System (EFFIS). The CLC is a part of the European Commission programme to COoRdinate INformation on the Environment (Corine) and it provides consistent, reliable and comparable information on land cover across Europe. Both the CLC and EFFIS datasets were combined using geostatistics and Geographical Information System (GIS) techniques to access the spatial and temporal evolution of the types of shrubs and forest affected by fires. Obtained results confirms the usefulness and efficiency of the land cover classification scheme and fire proneness index which allows to quantify and to compare the propensity of vegetation classes and countries to fire. As expected, differences between northern and southern Europe are notorious in what concern to land cover distribution, fire incidence and fire proneness of vegetation cover classes. This work was supported by national funds by FCT - Portuguese Foundation for Science and Technology, under the project PEst-OE/AGR/UI4033/2014 and by

  12. Vegetative propagation of Bambusa vulgaris

    Directory of Open Access Journals (Sweden)

    Rafael Malfitano Braga


    Full Text Available Bamboo is an important source of raw material of multiple uses. The development of simple techniques for its propagation is a practical way to enable its implementation in ownership of low technology. The present work had the objective of evaluating artisanal propagation methods for Bambusa vulgaris. Two types of propagules were tested, with buds budded or not, and three relative positions to the removal of vegetative material on the culm. The best propagule was with only one node, extracted from the lower thirds of the stem, presenting 72% of rooting. This result demonstrates its potential for seedling production of this species under low tech.

  13. Vegetable oils as diesel fuel

    International Nuclear Information System (INIS)

    Fedeli, E.; Girelli, A.


    During the seventies, one of the recurring fuels crisis gave rise to research on alternative sources and among them to the idea of utilizing vegetable oils. The research work made clear that the oils cannot be utilized as such but they must be transformed in simple esters, eliminating the problems arising from the presence of the glycerine. The Experiment Stations of the Industry, Commerce and Handicraft Department of the Italian Government, by request of the last one, in the '70/'80 has done a successful experimentation that is presented in the paper [it

  14. Acid precipitation and forest vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, C O; Cowling, E B


    Effects of acidic precipitation on forest vegetation may be classified as being either direct or indirect. Among the most important direct effects are damage to protective cuticular layers, interference with normal functioning of guard cells, poisoning of plant cells after diffusion of acidic substances through stomata or cuticle and interference with reproductive processes. Indirect effects include accelerated leaching of substances from foliar organs, increased susceptibility to drought and other environmental stress factors, and alteration of symbiotic associations and host-parasite interactions. The potential importance of nutrient uptake through foliage and the need to understand atmosphere-plant-soil interactions are stressed.

  15. Application of Two Quality Indices as Monitoring and Management Tools of Rivers. Case Study: The Imera Meridionale River, Italy (United States)

    Bonanno, Giuseppe; Giudice, Rosa Lo


    On the basis of the European Water Framework Directive (2000/60), the water resources of the member states of the European Community should reach good quality standards by 2015. Although such regulations illustrate the basic points for a comprehensive and effective policy of water monitoring and management, no practical tools are provided to face and solve the issues concerning freshwater ecosystems such as rivers. The Italian government has developed a set of regulations as adoption of the European Directive but failed to indicate feasible procedures for river monitoring and management. On a local scale, Sicilian authorities have implemented monitoring networks of watersheds, aiming at describing the general conditions of rivers. However, such monitoring programs have provided a relatively fragmentary picture of the ecological conditions of the rivers. In this study, the integrated use of environmental quality indices is proposed as a methodology able to provide a practical approach to river monitoring and management. As a case study, the Imera Meridionale River, Sicily’s largest river, was chosen. The water quality index developed by the U.S. National Sanitation Foundation and the floristic quality index based on the Wilhelm method were applied. The former enabled us to describe the water quality according to a spatial-temporal gradient, whereas the latter focused on the ecological quality of riparian vegetation. This study proposes a holistic view of river ecosystems by considering biotic and abiotic factors in agreement with the current European regulations. How the combined use of such indices can guide sustainable management efforts is also discussed.

  16. Tracking changes of river morphology in Ayeyarwady River in Myanmar using earth observations and surface water mapping tool (United States)

    Piman, T.; Schellekens, J.; Haag, A.; Donchyts, G.; Apirumanekul, C.; Hlaing, K. T.


    River morphology changes is one of the key issues in Ayeyarwady River in Myanmar which cause impacts on navigation, riverine habitats, agriculture lands, communities and livelihoods near the bank of the river. This study is aimed to track the changes in river morphology in the middle reach of Ayeyarwady River over last 30 years from 1984-2014 to improve understanding of riverbank dynamic, erosion and deposition procress. Earth observations including LandSat-7, LandSat-8, Digital Elevation Model from SRTM Plus and, ASTER-2 GoogleMap and Open Street Map were obtained for the study. GIS and remote sensing tools were used to analyze changes in river morphology while surface water mapping tool was applied to determine how the dynamic behaviour of the surface river and effect of river morphology changes. The tool consists of two components: (1) a Google Earth Engine (GEE) javascript or python application that performs image analysis and (2) a user-friendly site/app using Google's that exposes the application to the users. The results of this study shown that the fluvial morphology in the middle reach of Ayeyarwady River is continuously changing under the influence of high water flows in particularly from extreme flood events and land use change from mining and deforestation. It was observed that some meandering sections of the riverbank were straightened, which results in the movement of sediment downstream and created new sections of meandering riverbank. Several large islands have formed due to the stabilization by vegetation and is enforced by sedimentation while many small bars were formed and migrated dynamically due to changes in water levels and flow velocity in the wet and dry seasons. The main channel was changed to secondary channel in some sections of the river. This results a constant shift of the navigation route. We also found that some villages were facing riverbank erosion which can force villagers to relocate. The study results demonstrated

  17. Spatial-structural analysis of leafless woody riparian vegetation for hydraulic considerations (United States)

    Weissteiner, Clemens; Jalonen, Johanna; Järvelä, Juha; Rauch, Hans Peter


    Woody riparian vegetation is a vital element of riverine environments. On one hand woody riparian vegetation has to be taken into account from a civil engineering point of view due to boundary shear stress and vegetation drag. On the other hand it has to be considered from a river ecological point of view due to shadowing effects and as a source of organic material for aquatic habitats. In hydrodynamic and hydro-ecological studies the effects of woody riparian vegetation on flow patterns are usually investigated on a very detailed level. On the contrary vegetation elements and their spatial patterns are generally analysed and discussed on the basis of an integral approach measuring for example basal diameters, heights and projected plant areas. For a better understanding of the influence of woody riparian vegetation on turbulent flow and on river ecology, it is essential to record and analyse plant data sets on the same level of quality as for hydrodynamic or hydro-ecologic purposes. As a result of the same scale of the analysis it is possible to incorporate riparian vegetation as a sub-model in the hydraulic analysis. For plant structural components, such as branches on different topological levels it is crucial to record plant geometrical parameters describing the habitus of the plant on branch level. An exact 3D geometrical model of real plants allows for an extraction of various spatial-structural plant parameters. In addition, allometric relationships help to summarize and describe plant traits of riparian vegetation. This paper focuses on the spatial-structural composition of leafless riparia woddy vegetation. Structural and spatial analyses determine detailed geometric properties of the structural components of the plants. Geometrical and topological parameters were recorded with an electro-magnetic scanning device. In total, 23 plants (willows, alders and birches) were analysed in the study. Data were recorded on branch level, which allowed for the

  18. Satellite remote sensing of river inundation area, stage, and discharge: a review (United States)

    Smith, Laurence C.


    The growing availability of multi-temporal satellite data has increased opportunities for monitoring large rivers from space. A variety of passive and active sensors operating in the visible and microwave range are currently operating, or planned, which can estimate inundation area and delineate flood boundaries. Radar altimeters show great promise for directly measuring stage variation in large rivers. It also appears to be possible to obtain estimates of river discharge from space, using ground measurements and satellite data to construct empirical curves that relate water surface area to discharge. Extrapolation of these curves to ungauged sites may be possible for the special case of braided rivers.Where clouds, trees and floating vegetation do not obscure the water surface, high-resolution visible/infrared sensors provide good delineation of inundated areas. Synthetic aperture radar (SAR) sensors can penetrate clouds and can also detect standing water through emergent aquatic plants and forest canopies. However, multiple frequencies and polarizations are required for optimal discrimination of various inundated vegetation cover types. Existing single-polarization, fixed-frequency SARs are not sufficient for mapping inundation area in all riverine environments. In the absence of a space-borne multi-parameter SAR, a synergistic approach using single-frequency, fixed-polarization SAR and visible/infrared data will provide the best results over densely vegetated river floodplains.

  19. Measurements and modelling of evapotransiration to assess agricultural water productivity in basins with changing land use patterns : a case study in the São Francisco River basin, Brazil

    NARCIS (Netherlands)

    Castro Teixeira, de A.H.


    Key words: Vineyards, mango, energy balance, evapotranspiration, water productivity, Bowen ratio, eddy correlation, water balance, natural vegetation, latent heat flux, sensible heat flux, biomass, water productivity, remote sensing, water management. . The São Francisco River basin in Brazil is

  20. The role of ice dynamics in shaping vegetation in flowing waters. (United States)

    Lind, Lovisa; Nilsson, Christer; Polvi, Lina E; Weber, Christine


    Ice dynamics is an important factor affecting vegetation in high-altitude and high-latitude streams and rivers. During the last few decades, knowledge about ice in streams and rivers has increased significantly and a respectable body of literature is now available. Here we review the literature on how ice dynamics influence riparian and aquatic vegetation. Traditionally, plant ecologists have focused their studies on the summer period, largely ignoring the fact that processes during winter also impact vegetation dynamics. For example, the freeze-up period in early winter may result in extensive formation of underwater ice that can restructure the channel, obstruct flow, and cause flooding and thus formation of more ice. In midwinter, slow-flowing reaches develop a surface-ice cover that accumulates snow, protecting habitats under the ice from formation of underwater ice but also reducing underwater light, thus suppressing photosynthesis. Towards the end of winter, ice breaks up and moves downstream. During this transport, ice floes can jam up and cause floods and major erosion. The magnitudes of the floods and their erosive power mainly depend on the size of the watercourse, also resulting in different degrees of disturbance to the vegetation. Vegetation responds both physically and physiologically to ice dynamics. Physical action involves the erosive force of moving ice and damage caused by ground frost, whereas physiological effects - mostly cell damage - happen as a result of plants freezing into the ice. On a community level, large magnitudes of ice dynamics seem to favour species richness, but can be detrimental for individual plants. Human impacts, such as flow regulation, channelisation, agriculturalisation and water pollution have modified ice dynamics; further changes are expected as a result of current and predicted future climate change. Human impacts and climate change can both favour and disfavour riverine vegetation dynamics. Restoration of streams

  1. Lead and zinc contamination of vegetation in the southern Pennines

    Energy Technology Data Exchange (ETDEWEB)

    Shimwell, D W; Laurie, A E


    Three types of heavy metal tolerant vegetation occurring on the spoil heaps in the Pennines are described sociologically and ecologically and their distribution in the Peak District National Park mapped. Concentrations of lead and zinc extractable from soils by acetic acid are recorded, as are total values for these two heavy metals in the tissues of the main component phanerogams and cryptogams of the vegetation. The range of values for zinc in plant tissues are uniformly higher than those for lead. Concentrations of lead accumulated by these plants are higher than those reported for the accumulation of atmospheric lead. The differences in heavy metal absorption, retention and excretion between ectohydric and myxohydric mosses are shown to be quite distinct. The heavy metals are excreted in the former type and form a crust in periods of drought with up to 6% lead and 1.5% zinc content, while, in the latter, the metals tend to be located mainly in the older growth at the base of the moss carpets. The concentrations of the two metal ions in two Peak District rivers proved to be less than 1 ppm in all samples.

  2. Texture classification of vegetation cover in high altitude wetlands zone

    International Nuclear Information System (INIS)

    Wentao, Zou; Bingfang, Wu; Hongbo, Ju; Hua, Liu


    The aim of this study was to investigate the utility of datasets composed of texture measures and other features for the classification of vegetation cover, specifically wetlands. QUEST decision tree classifier was applied to a SPOT-5 image sub-scene covering the typical wetlands area in Three River Sources region in Qinghai province, China. The dataset used for the classification comprised of: (1) spectral data and the components of principal component analysis; (2) texture measures derived from pixel basis; (3) DEM and other ancillary data covering the research area. Image textures is an important characteristic of remote sensing images; it can represent spatial variations with spectral brightness in digital numbers. When the spectral information is not enough to separate the different land covers, the texture information can be used to increase the classification accuracy. The texture measures used in this study were calculated from GLCM (Gray level Co-occurrence Matrix); eight frequently used measures were chosen to conduct the classification procedure. The results showed that variance, mean and entropy calculated by GLCM with a 9*9 size window were effective in distinguishing different vegetation types in wetlands zone. The overall accuracy of this method was 84.19% and the Kappa coefficient was 0.8261. The result indicated that the introduction of texture measures can improve the overall accuracy by 12.05% and the overall kappa coefficient by 0.1407 compared with the result using spectral and ancillary data

  3. 488-D Ash Basin Vegetative Cover Treatibility Study

    Energy Technology Data Exchange (ETDEWEB)

    Barton, Christopher; Marx, Don; Blake, John; Adriano, Domy; Koo, Bon-Jun; Czapka, Stephen


    The 488-D Ash Basin is an unlined containment basin that received ash and coal reject material from the operation of a powerhouse at the USDOE's Savannah River Site, SC. They pyretic nature of the coal rejects has resulted in the formation of acidic drainage (AD), which has contributed to groundwater deterioration and threatens biota in down gradient wetlands. Establishment of a vegetative cover was examined as a remedial alternative for reducing AD generation within this system by enhanced utilization of rainwater and subsequent non-point source water pollution control. The low nutrient content, high acidity, and high salinity of the basin material, however, was deleterious to plant survivability. As such, studies to identify suitable plant species and potential adaptations, and pretreatment techniques in the form of amendments, tilling, and/or chemical stabilization were needed. A randomized block design consisting of three subsurface treatments (blocks) and five duplicated surface amendments (treatments) was developed. One hundred inoculated pine trees were planted on each plot. Herbaceous species were also planted on half of the plots in duplicated 1-m2 beds. After two growing seasons, deep ripping, subsurface amendments and surface covers were shown to be essential for the successful establishment of vegetation on the basin. This is the final report of the study.

  4. Intimations on the Tertiary vegetation of southern Africa

    Directory of Open Access Journals (Sweden)

    J. A. Coetzee


    Full Text Available Fossil pollen sequences from the Cape Peninsula and the Saldanha region indicate that sub tropical vegetation and climates existed in these regions during the Miocene. The pollen record from the Cape Peninsula may point to the extinction of some taxa by the terminal Miocene/Early Pliocene with the subsequent strong development of macchia. This major change can probably be related to the maximum build-up of the Antarctic ice-cap in the latest Miocene and the accompanying profound palaeoceanographic changes such as the major cooling of the Benguela current with its effect on the aridification of the Namib desert, and the global glacio-eustatic sea level drop.Parallel palynological and lithological studies in the Saldanha region show that prominent Miocene vegetation shifts were linked to profound local changes in the palaeoenvironment associated with the northward migration of the Miocene Berg River. Such studies are of paramount importance for the possible assessment of the causes of changes in the palaeoenvironment and should first be carried out at many more sites over a wide region. It is to some extent premature to draw firm conclusions as to the origin and migration of some taxa in southern Africa. The record of very primitive angiosperms such as the ClavatipolleniteslAscarina complex and Winteraceae is of considerable phytogeographic interest.

  5. The Hydromechanics of Vegetation for Slope Stabilization (United States)

    Mulyono, A.; Subardja, A.; Ekasari, I.; Lailati, M.; Sudirja, R.; Ningrum, W.


    Vegetation is one of the alternative technologies in the prevention of shallow landslide prevention that occurs mostly during the rainy season. The application of plant for slope stabilization is known as bioengineering. Knowledge of the vegetative contribution that can be considered in bioengineering was the hydrological and mechanical aspects (hydromechanical). Hydrological effect of the plant on slope stability is to reduce soil water content through transpiration, interception, and evapotranspiration. The mechanical impact of vegetation on slope stability is to stabilize the slope with mechanical reinforcement of soils through roots. Vegetation water consumption varies depending on the age and density, rainfall factors and soil types. Vegetation with high ability to absorb water from the soil and release into the atmosphere through a transpiration process will reduce the pore water stress and increase slope stability, and vegetation with deep root anchoring and strong root binding was potentially more significant to maintain the stability of the slope.

  6. The water quality of the river Svratka and its tributaries

    Directory of Open Access Journals (Sweden)

    Jan Grmela


    Full Text Available Water quality in river depends on water quality of its tributaries. During the year 2011 nine selected sites downstream under the Vír dam (from 108 to 79 river km were monitored. For observation were chosen tributaries Besének, Loučka, Nedvědička, Chlebský creek, Hodonínka, Vrtěžířský creek and Tresný creek. At the same time samples from the places above and under the whole monitored section of the river were taken. Basic physicochemical parameters were monitored monthly during the vegetation period. Flow velocity and discharge were assessed three times. Based on the water quality evaluation of, the river Svratka and its tributaries Hodonínka, Vrtěžířský creek and Tresný creek belong to the second quality class, tributaries Besének, Loučka, Nedvědička and Chlebský belong to the third quality class. In the monitored section the retention of phosphorus in annual amount about 2.2 tons were occurance. Annual volume of phosphorus at the end of observed section (upstream the Tišnov town was nearly 17.5 tons. Annual total balance of nitrogen at the end of monitored section was 700 tons per year and 6000 tons of carbon per year. The major source of these nutrients is the river Loučka.

  7. Uncertainty in river discharge observations: a quantitative analysis

    Directory of Open Access Journals (Sweden)

    G. Di Baldassarre


    Full Text Available This study proposes a framework for analysing and quantifying the uncertainty of river flow data. Such uncertainty is often considered to be negligible with respect to other approximations affecting hydrological studies. Actually, given that river discharge data are usually obtained by means of the so-called rating curve method, a number of different sources of error affect the derived observations. These include: errors in measurements of river stage and discharge utilised to parameterise the rating curve, interpolation and extrapolation error of the rating curve, presence of unsteady flow conditions, and seasonal variations of the state of the vegetation (i.e. roughness. This study aims at analysing these sources of uncertainty using an original methodology. The novelty of the proposed framework lies in the estimation of rating curve uncertainty, which is based on hydraulic simulations. These latter are carried out on a reach of the Po River (Italy by means of a one-dimensional (1-D hydraulic model code (HEC-RAS. The results of the study show that errors in river flow data are indeed far from negligible.

  8. Flora of the Kap River Reserve, Eastern Cape, South Africa

    Directory of Open Access Journals (Sweden)

    E. C. Cloete


    Full Text Available A detailed analysis ot the flora of the newly proclaimed Kap River Reserve (600 ha is given. The reserve is adjacent to the Fish River and some 5 km from the Fish River Mouth It consists of a coastal plateau up to 100 m a.s.I. which is steeply dissected by the two rivers that partially form the boundary of the reserve. The flora of the reserve was sampled over a period o f three years and plants were collected in all the vegetation types of grassland, thicket and forest. 488 species were collected with a species to family ratio of 4:4. The majority of the taxa recorded represent the major phytochoria of the region. Nineteen species are endemic to the Eastern Cape, two are classed as vulnerable, five are rare, six are protected and a further seventeen are of uncertain status. The flora of the Kap River has closest affinities to that of the Alexandria Forest.

  9. Land degradation trends in upper catchments and morphological developments of braided rivers in drylands: the case of a marginal graben of the Ethiopian Rift Valley (United States)

    Demissie, Biadgilgn; Frankl, Amaury; Haile, Mitiku; Nyssen, Jan


    Braided rivers have received relatively little attention in research and development activities in drylands. However, they strongly impact agroecology and agricultural activities and thereby local livelihoods. The Raya Graben (3750 km² including the escarpment) is a marginal graben of the Ethiopian Rift Valley located in North Ethiopia. In order to study the dynamics of braided rivers and the relationship with biophysical controls, 20 representative catchments were selected, ranging between 15 and 311 km². First, the 2005 morphology (length, area) of the braided rivers was related to biophysical controls (vegetation cover, catchment area and slope gradient in the steep upper catchments and gradient in the graben bottom). Second, the changes in length of the braided rivers were related to vegetation cover changes in the upper catchments since 1972. Landsat imagery was used to calculate the Normalized Difference Vegetation Index (NDVI), and to map vegetation cover and the total length of the braided rivers. Spot CNES imagery available from Google Earth was used to identify the total area of the braided rivers in 2005. A linear regression analysis revealed that the length of braided rivers was positively related to the catchment area (R²=0.32, p<0.01), but insignificantly related to vegetation cover in the upper catchments. However, there is an indication that it is an important factor in the relationship calculated for 2005 (R²=0.2, p=0.064). Similarly, the area occupied by the braided rivers was related to NDVI (R²=0.24, p<0.05) and upper catchment area (R²=0.447, p<0.01). Slope gradient is not an important explanatory factor. This is related to the fact that slope gradients are steep (average of 38.1%) in all upper and gentle (average of 3.4%) in graben bottom catchments. The vegetation cover in the upper catchments shows a statistically insignificant increasing trend (R²=0.73, p=0.067) over the last 40 years, whereas length of rivers in the graben bottom

  10. [Health assessment of river ecosystem in Haihe River Basin, China]. (United States)

    Hao, Li-Xia; Sun, Ran-Hao; Chen, Li-Ding


    With the development of economy, the health of river ecosystem is severely threatened because of the increasing effects of human activities on river ecosystem. In this paper, the authors assessed the river ecosystem health in aspects of chemical integrity and biological integrity, using the criterion in water quality, nutrient, and benthic macroinvertebrates of 73 samples in Haihe River Basin. The research showed that the health condition of river ecosystem in Haihe River Basin was bad overall since the health situation of 72. 6% of the samples was "extremely bad". At the same time, the health situation in Haihe River Basin exhibited obvious regional gathering effect. We also found that the river water quality was closely related to human activities, and the eutrophication trend of water body was evident in Haihe River Basin. The biodiversity of the benthic animal was low and lack of clean species in the basin. The indicators such as ammonia nitrogen, total nitrogen and total phosphorus were the key factors that affected the river ecosystem health in Haihe River Basin, so the government should start to curb the deterioration of river ecosystem health by controlling these nutrients indicators. For river ecosystem health assessment, the multi-factors comprehensive evaluation method was superior to single-factor method.

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

    Directory of Open Access Journals (Sweden)

    Fabio Cop Ferreira


    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.

  12. Vegetation types and forest productivity, west part of Syncrude's Lease 17, Alberta. Environmental Research Monography 1977-6. [Tar sands

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, E B; Levinsohn, A G


    The vegetation that existed in August 1977 on the western half of Syncrude's Lease 17 near Fort McMurray, Alberta is described. Eight vegetation types were identified and are mapped at a scale if 1 : 24,000. Black Spruce--Labrador Tea was the dominant vegetation type, making up 35.0% of the 9250 hectare study area. The second most abundant vegetation type was Aspen--White Spruce (26.0%) and the third was White Spruce--Aspen (18.0%). The remaining 21.0% of the area was occupied by the Aspen--Birch vegetation type (7.5%), Balsam Poplar--Alder (6.0%) along the McKay River, Sedge--Reed Grass (4.0%) mainly around bodies of standing water created by beaver dams, Willow--Reed Grass (3.0%) along stream courses, and Black Spruce--Feathermoss (0.5%). The White Spruce--Aspen type is best developed in the southern part of the lease. It is the only vegetation type that contains some white spruce stands approaching the present lower limits of merchantable forest in Alberta. The Aspen--White Spruce type was less productive. In terms of mean annual increment and site index, the two vegetation types with the greatest potential for fibre production (White Spruce--Aspen and Aspen--White Spruce types) are average or below average productivity when compared to data from similar stands elsewhere in Alberta and Saskatchewan.

  13. The marsh vegetation of Kleinmond Lagoon

    Directory of Open Access Journals (Sweden)

    M. O'Callaghan


    Full Text Available The vegetation of Kleinmond Lagoon suggests that this system is in transition from an estuary to a coastal lake. Two major types of vegetation were recognized, one which is subjected to soil and water conditions of marine origin and the other which is subjected to conditions of terrestrial origin. These vegetation types are discussed and compared to the vegetation of other estuarine systems. Artificial manipulations of the mouth seem to have resulted in sediment deposition and a freshening of the system. These unseasonable manipulations also threaten the continued existence of a number of species in the system.

  14. Submersed Aquatic Vegetation Modeling Output Online

    National Research Council Canada - National Science Library

    Yin, Yao; Rogala, Jim; Sullivan, John; Rohweder, Jason


    .... Predictions for distribution of submerged aquatic vegetation beds can potentially increase hunter observance of voluntary avoidance zones where foraging birds are left alone to feed undisturbed...

  15. Importance of considering riparian vegetation requirements for the long-term efficiency of environmental flows in aquatic microhabitats

    Directory of Open Access Journals (Sweden)

    R. Rivaes


    Full Text Available Environmental flows remain biased toward the traditional biological group of fish species. Consequently, these flows ignore the inter-annual flow variability that rules species with longer lifecycles and therefore disregard the long-term perspective of the riverine ecosystem. We analyzed the importance of considering riparian requirements for the long-term efficiency of environmental flows. For that analysis, we modeled the riparian vegetation development for a decade facing different environmental flows in two case studies. Next, we assessed the corresponding fish habitat availability of three common fish species in each of the resulting riparian landscape scenarios. Modeling results demonstrated that the environmental flows disregarding riparian vegetation requirements promoted riparian degradation, particularly vegetation encroachment. Such circumstance altered the hydraulic characteristics of the river channel where flow depths and velocities underwent local changes of up to 10 cm and 40 cm s−1, respectively. Accordingly, after a decade of this flow regime, the available habitat area for the considered fish species experienced modifications of up to 110 % when compared to the natural habitat. In turn, environmental flows regarding riparian vegetation requirements were able to maintain riparian vegetation near natural standards, thereby preserving the hydraulic characteristics of the river channel and sustaining the fish habitat close to the natural condition. As a result, fish habitat availability never changed more than 17 % from the natural habitat.

  16. Savannah River Site Environmental Report for 1994

    International Nuclear Information System (INIS)

    Arnett, M.W.; Mamatey, A.; Spitzer, D.


    The mission at the Savannah River Site has changed from producing nuclear weapons materials for national defense to managing the waste it has generated, restoring the environment, and enhancing industrial development in and around the site. But no matter what the site's mission is, it will continue to maintain its comprehensive environmental monitoring and surveillance program. In 1994, effluent monitoring and environmental surveillance were conducted within a 30,000-square-mile area in and around SRS that includes neighboring cities, towns, and counties in Georgia and South Carolina and extends up to 100 miles from the site. Thousands of samples of air, surface water, groundwater, foodstuffs, drinking water, wildlife, rainwater, soil, sediment, and vegetation were collected and analyzed for radioactive and nonradioactive contaminants

  17. Savannah River Site Environmental Report for 1994

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.W.; Mamatey, A.; Spitzer, D.


    The mission at the Savannah River Site has changed from producing nuclear weapons materials for national defense to managing the waste it has generated, restoring the environment, and enhancing industrial development in and around the site. But no matter what the site`s mission is, it will continue to maintain its comprehensive environmental monitoring and surveillance program. In 1994, effluent monitoring and environmental surveillance were conducted within a 30,000-square-mile area in and around SRS that includes neighboring cities, towns, and counties in Georgia and South Carolina and extends up to 100 miles from the site. Thousands of samples of air, surface water, groundwater, foodstuffs, drinking water, wildlife, rainwater, soil, sediment, and vegetation were collected and analyzed for radioactive and nonradioactive contaminants.

  18. Savannah River Site environmental data for 1993

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.W. [ed.


    The figures and tables in this report represent a capsule view of the routine environmental monitoring and surveillance programs at the Savannah River Site. An attempt has been made to include all available data from environmental research programs. The first section of the book is a collection of maps of radiological and nonradiological sampling locations. Also included are general radiological and nonradiological sampling and analysis schedules; a list of the media sampled, along with sample sizes and representative aliquots; a list of the lower limits of detection for radiological detection instruments; the minimum detectable concentrations for gamma analysis of water and air samples; and the minimum detectable concentrations for gamma analysis of soil, food, fish and wildlife, and vegetation samples. Following the first section are data tables containing radiological and nonradiological effluent monitoring results, radiological and nonradiological environmental surveillance results, dose estimates, quality assurance activities, and results of nonroutine occurrences and special surveys.

  19. Impact of vegetation dynamics on hydrological processes in a semi-arid basin by using a land surface-hydrology coupled model

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Yang; Lei, Huimin; Yang, Dawen; Huang, Maoyi; Liu, Dengfeng; Yuan, Xing


    Land surface models (LSMs) are widely used to understand the interactions between hydrological processes and vegetation dynamics, which is important for the attribution and prediction of regional hydrological variations. However, most LSMs have large uncertainties in their representations of ecohydrological processes due to deficiencies in hydrological parameterizations. In this study, the Community Land Model version 4 (CLM4) LSM was modified with an advanced runoff generation and flow routing scheme, resulting in a new land surface-hydrology coupled model, CLM-GBHM. Both models were implemented in the Wudinghe River Basin (WRB), which is a semi-arid basin located in the middle reaches of the Yellow River, China. Compared with CLM, CLM-GBHM increased the Nash Sutcliffe efficiency for daily river discharge simulation (1965–1969) from 0.03 to 0.23 and reduced the relative bias in water table depth simulations (2010–2012) from 32.4% to 13.4%. The CLM-GBHM simulations with static, remotely sensed and model-predicted vegetation conditions showed that the vegetation in the WRB began to recover in the 2000s due to the Grain for Green Program but had not reached the same level of vegetation cover as regions in natural eco-hydrological equilibrium. Compared with a simulation using remotely sensed vegetation cover, the simulation with a dynamic vegetation model that considers only climate-induced change showed a 10.3% increase in evapotranspiration, a 47.8% decrease in runoff, and a 62.7% and 71.3% deceleration in changing trend of the outlet river discharge before and after the year 2000, respectively. This result suggests that both natural and anthropogenic factors should be incorporated in dynamic vegetation models to better simulate the eco-hydrological cycle.

  20. Upper Mississippi River Land Use Allocation Plan. Master Plan for Public Use Development and Resource Management. Parts 1 and 2. (United States)


    most common understo wood nettle , poison ivy, wild grape, Dominant overstory species in better-di BIOLOGICAL RESOURCES are American elm, silver maple...aquatic vegetation associated with er of commonness. The most backwater areas are examples of such low-capability es are woodbine, wood nettle , class...and of aquatic invertebrates. Benthic organisms, partic- River) in the river’s side chani ularly aquatic insects and freshwater mussels, are border

  1. Volatilization of iodine from vegetation

    International Nuclear Information System (INIS)

    Amiro, B.D.; Johnston, F.L.


    Gaseous emissions of iodine were measured from bean plant foliage. A gamma-emitting iodine tracer, Na 125 I, was taken up by the plants from a hydroponic growth medium and released to a cuvette atmosphere. The dynamics of the flux were studied using a flow-through gamma detector. The relationship between leaf radioactive tracer activity and growth-medium activity was linear, as was the relationship between the iodine flux and both leaf and growth-medium activity. Iodine flux and leaf conductance to water responded similarly to changes in light levels, suggesting that the stomata may partially control the flux. The flux was inhibited by aeration of the hydroponic growth media, and we postulate that methylation causes the iodine flux. Iodine emissions from living vegetation probably contribute < 0.1% to the stable iodine concentration in the atmosphere above terrestrial areas. However, this pathway may be a direct route for radioactive iodine transport from contaminated soils to the atmosphere. (author)

  2. Vegetable oil basestocks for lubricants

    Directory of Open Access Journals (Sweden)

    Garcés, Rafael


    Full Text Available The use of vegetable biodegradable basestocks for lubricant oils present several advantages over the much more extended mineral bases. These advantages refer to biodegradability, a renewable feedstock of local production, lubricant and viscosity index and lower costs than synthetic lubricant bases. Despite these benefits, their use in industry and motor vehicles is not yet extensive due their lower stability and higher pour points. Vegetable oils are esters of fatty acids and glycerol, and their physicochemical properties rely mainly on the composition of their acyl moieties. Thus, to assure the maximum levels of stability while maintaining acceptable behavior at low temperatures, monounsaturated fatty acids are preferred for this purpose. The presence of natural antioxidants also improves the properties of these vegetable based stocks as lubricants. These oils usually require additives to improve their viscosity value, oxidative stability and properties at low temperatures. In the present work, the different sources of vegetable oils appropriate for biolubricant production were reviewed. Their properties and the future improvement of the oil bases, oil based stock production, uses and additives are discussed.

    El uso de bases vegetales biodegradables para aceites lubricantes presenta varias ventajas sobre las mucho más extendidas bases minerales. Estas ventajas se centran sobre todo en su biodegradabilidad, en ser un recurso renovable de producción local, en su lubricidad y en su índice de viscosidad, presentando además costes más bajos que las bases sintéticas. Sin embargo, estas ventajas no han extendido el uso de bases vegetales ni en industria ni en automoción debido a su menor estabilidad y sus mayores puntos críticos de fluidez. Los aceites vegetales son ésteres de ácidos grasos y glicerol y sus propiedades físico-químicas dependen principalmente de su composición acílica. Así, para asegurar los máximos niveles de

  3. Designing and Assessing Restored Meandering River Planform Using RVR Meander (United States)

    Langendoen, E. J.; Abad, J. D.; Motta, D.; Frias, C. E.; Wong, M.; Barnes, B. J.; Anderson, C. D.; Garcia, M. H.; MacDonald, T. E.


    The ongoing modification and resulting reduction in water quality of U.S. rivers have led to a significant increase in river restoration projects over the last two decades. The increased interest in restoring degraded streams, however, has not necessarily led to improved stream function. Palmer and Allan (2005) found that many restoration projects fail to achieve their objectives due to the lack of policies to support restoration standards, to promote proven methods and to provide basic data needed for planning and implementation. Proven models of in-stream and riparian processes could be used not only to guide the design of restoration projects but also to assess both pre- and post-project indicators of ecological integrity. One of the most difficult types of river restoration projects concern reconstructing a new channel, often with an alignment and channel form different from those of the degraded pre-project channel. Recreating a meandering planform to provide longitudinal and lateral variability of flow and bed morphology to improve in-stream aquatic habitat is often desired. Channel meander planform is controlled by a multitude of variables, for example channel width to depth ratio, radius of curvature to channel width ratio, bankfull discharge, roughness, bed-material physical characteristics, bed material transport, resistance to erosion of the floodplain soils, riparian vegetation, etc. Therefore, current practices that use simple, empirically based relationships or reference reaches have led to failure in several instances, for example a washing out of meander bends or a highly unstable planform, because they fail to address the site-specific conditions. Recently, progress has been made to enhance a physically- and process-based model, RVR Meander, for rapid analysis of meandering river morphodynamics with reduced empiricism. For example, lateral migration is based on measurable physical properties of the floodplain soils and riparian vegetation versus

  4. Changes in Remotely Sensed Vegetation Growth Trend in the Heihe Basin of Arid Northwestern China.

    Directory of Open Access Journals (Sweden)

    Wenchao Sun

    Full Text Available The Heihe River Basin (HRB is the second largest inland river basin in China, characterized by high diversity in geomorphology and irrigated agriculture in middle reaches. To improve the knowledge about the relationship between biotic and hydrological processes, this study used Global Inventory Modeling and Mapping Studies Normalized Difference Vegetation Index (NDVI data (1982-2006 to analyze spatiotemporal variations in vegetation growth by using the Mann-Kendall test together with Sen's slope estimator. The results indicate that 10.1% and 1.6% of basin area exhibit statistically significant (p < 0.05 upward and downward trends, and maximum magnitude is 0.066/10a and 0.026/10a, respectively. More specifically, an increasing trend was observed in the Qilian Mountains and Hexi Corridor and a decreasing trend detected in the transitional region between them. Increases in precipitation and temperature may be one possible reason for the changes of vegetation growth in the Qilian Mountains. And decreasing trend in transitional region may be driven by the changes in precipitation. Increases of irrigation contribute to the upward trend of NDVI for cropland in the Hexi Corridor, reflecting that agricultural development becomes more intensive. Our study demonstrates the complexity of the response of vegetation growth in the HRB to climate change and anthropogenic activities and correspondingly adopting mechanistic ecological models capable of describing both factors is favorable for reasonable predictions of future vegetation growth. It is also indicated that improving irrigation water use efficiency is one practical strategy to balance water demand between human and natural ecosystems in the HRB.

  5. The relation of vegetation over the Tibetan Plateau to rainfall in China during the boreal summer

    Energy Technology Data Exchange (ETDEWEB)

    Zuo, Zhiyan; Zhang, Renhe [Chinese Academy of Meteorological Sciences, State Key Laboratory of Severe Weather, Beijing (China); Zhao, Ping [National Meteorological Information Centre, Beijing (China)


    The relationship between vegetation on the Tibetan Plateau (TP) and summer (June-August) rainfall in China is investigated using the normalized difference vegetation index (NDVI) from the Earth Resources Observation System and observed rainfall data from surface 616 stations in China for the period 1982-2001. The leading mode of empirical orthogonal functions analysis for summer rainfall variability in China shows a negative anomaly in the area from the Yangtze River valley to the Yellow River valley (YYR) and most of western China, and positive anomalies in southern China and North China. This mode is significantly correlated with summer NDVI around the southern TP. This finding indicates that vegetation around the southern TP has a positive correlation with summer rainfall in southern China and North China, but a negative correlation with summer rainfall in YYR and western China. We investigate the physical process by which vegetation change affects summer rainfall in China. Increased vegetation around the southern TP is associated with a descending motion anomaly on the TP and the neighboring area to the east, resulting in reduced surface heating and a lower Bowen ratio, accompanied by weaker divergence in the upper troposphere and convergence in the lower troposphere on the TP. In turn, these changes result in the weakening of and a westward shift in the southern Asian High in the upper troposphere and thereby the weakening of and an eastward withdrawal in the western Pacific subtropical high. These features result in weak circulation in the East Asian summer monsoon. Consequently, enhanced summer rainfall occurs in southern China and North China, but reduced rainfall in YYR. (orig.)

  6. Biological indication with the aid of submerged vegetation - potential and limits; Bioindikation mit Hilfe Hoeherer Wasserpflanzen - Moeglichkeiten und Grenzen

    Energy Technology Data Exchange (ETDEWEB)

    Schuetz, W.


    From 1986 to 1989 the submerged vegetation of the running waters of the `Schwaebische Alb` and `Oberschwaben` were investigated. The qualitative and quantitative distribution of macrophytes depends in the first place on the occurence of extreme discharges overlaying other factors influencing the distribution of macrophytes (trophical state). The effects of increasing eutrophication can be proved, too, by reconstructing the increase resp. decrease of suitable indicator-species [Groenlandia densa (L.) FOURR.] within a larger area. The effects of water-regulation measures with ensueing eutrophication can be demonstrated in the specific case of the submerged vegetation of the Danube river and the `suedbadische Oberrheinaue`. (orig.)

  7. Least Disturbed Condition for European Mediterranean rivers. (United States)

    Feio, M J; Aguiar, F C; Almeida, S F P; Ferreira, J; Ferreira, M T; Elias, C; Serra, S R Q; Buffagni, A; Cambra, J; Chauvin, C; Delmas, F; Dörflinger, G; Erba, S; Flor, N; Ferréol, M; Germ, M; Mancini, L; Manolaki, P; Marcheggiani, S; Minciardi, M R; Munné, A; Papastergiadou, E; Prat, N; Puccinelli, C; Rosebery, J; Sabater, S; Ciadamidaro, S; Tornés, E; Tziortzis, I; Urbanič, G; Vieira, C


    The present report describes a three-step approach that was used to characterize and define thresholds for the Least Disturbed Condition in Mediterranean streams of four different types, regarding organic pollution and nutrients, hydrological and morphological alterations, and land use. For this purpose, a common database composed of national reference sites (929 records) from seven countries, sampled for invertebrates, diatoms and macrophytes was used. The analyses of reference sites showed that small (catchment rivers were the most affected by stressors: 25-43% of the samples showed at least slight alterations regarding channelization, connectivity, upstream dam influence, hydropeaking and degradation of riparian vegetation. Temporary streams were the least affected by hydromorphological changes, but they were nevertheless affected by alterations in riparian vegetation. There were no major differences between all permanent stream types regarding water quality, but temporary streams showed lower values for oxygenation (DO) and wider ranges for other variables, such as nitrates. A lower threshold value for DO (60%) was determined for this stream type and can be attributed to the streams' natural characteristics. For all other river types, common limits were found for the remaining variables (ammonium, nitrate, phosphate, total P, % of artificial areas, % of intensive and extensive agriculture, % of semi-natural areas in the catchment). These values were then used to select the list of reference sites. The biological communities were characterized, revealing the existence of nine groups of Mediterranean invertebrate communities, six for diatoms and five for macrophytes: each group was characterized by specific indicator taxa that highlighted the differences between groups. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. BLAM (Benthic Light Availability Model): A Proposed Model of Hydrogeomorphic Controls on Light in Rivers (United States)

    Julian, J. P.; Doyle, M. W.; Stanley, E. H.


    Light is vital to the dynamics of aquatic ecosystems. It drives photosynthesis and photochemical reactions, affects thermal structure, and influences behavior of aquatic biota. Despite the fundamental role of light to riverine ecosystems, light studies in rivers have been mostly neglected because i) boundary conditions (e.g., banks, riparian vegetation) make ambient light measurements difficult, and ii) the optical water quality of rivers is highly variable and difficult to characterize. We propose a benthic light availability model (BLAM) that predicts the percent of incoming photosynthetically active radiation (PAR) available at the river bed. BLAM was developed by quantifying light attenuation of the five hydrogeomorphic controls that dictate riverine light availability: topography, riparian vegetation, channel geometry, optical water quality, and water depth. BLAM was calibrated using hydrogeomorphic data and light measurements from two rivers: Deep River - a 5th-order, turbid river in central North Carolina, and Big Spring Creek - a 2nd-order, optically clear stream in central Wisconsin. We used a series of four PAR sensors to measure i) above-canopy PAR, ii) PAR above water surface, iii) PAR below water surface, and iv) PAR on stream bed. These measurements were used to develop empirical light attenuation coefficients, which were then used in combination with optical water quality measurements, shading analyses, channel surveys, and flow records to quantify the spatial and temporal variability in riverine light availability. Finally, we apply BLAM to the Baraboo River - a 6th-order, 120-mile, unimpounded river in central Wisconsin - in order to characterize light availability along the river continuum (from headwaters to mouth).

  9. 33 CFR 117.734 - Navesink River (Swimming River). (United States)


    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming River). 117.734 Section 117.734 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...

  10. Skjern River Restoration Counterfactual

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel


    In 2003 the Skjern River Restoration Project in Denmark was awarded the prestigious Europa Nostra Prize for ‘conserving the European cultural heritage’ (Danish Nature Agency 2005). In this case, however, it seems that the conservation of one cultural heritage came at the expense of another cultural...... this massive reconstruction work, which involved moving more than 2,7 million cubic meters of earth, cause a lot of ‘dissonance’ among the local population, the resulting ‘nature’ and its dynamic processes are also constantly compromising the preferred image of the restored landscape (Clemmensen 2014......). The presentation offers insight into an on-going research and development project - Skjern River Restoration Counterfactual, which question existing trends and logics within nature restoration. The project explores how the Skjern River Delta could have been ‘restored’ with a greater sensibility for its cultural...

  11. Assessment of floodplain vulnerability during extreme Mississippi River flood 2011. (United States)

    Goodwell, Allison E; Zhu, Zhenduo; Dutta, Debsunder; Greenberg, Jonathan A; Kumar, Praveen; Garcia, Marcelo H; Rhoads, Bruce L; Holmes, Robert R; Parker, Gary; Berretta, David P; Jacobson, Robert B


    Regional change in the variability and magnitude of flooding could be a major consequence of future global climate change. Extreme floods have the capacity to rapidly transform landscapes and expose landscape vulnerabilities through highly variable spatial patterns of inundation, erosion, and deposition. We use the historic activation of the Birds Point-New Madrid Floodway during the Mississippi and Ohio River Flooding of 2011 as a scientifically unique stress experiment to analyze indicators of floodplain vulnerability. We use pre- and postflood airborne Light Detection and Ranging data sets to locate erosional and depositional hotspots over the 540 km(2) agricultural Floodway. While riparian vegetation between the river and the main levee breach likely prevented widespread deposition, localized scour and deposition occurred near the levee breaches. Eroded gullies nearly 1 km in length were observed at a low ridge of a relict meander scar of the Mississippi River. Our flow modeling and spatial mapping analysis attributes this vulnerability to a combination of erodible soils, flow acceleration associated with legacy fluvial landforms, and a lack of woody vegetation to anchor soil and enhance flow resistance. Results from this study could guide future mitigation and adaptation measures in cases of extreme flooding.

  12. Children and vegetables: strategies to increase children’s liking and intake of vegetables

    NARCIS (Netherlands)

    Wild, de V.W.T.


    Background and aim

    Children’s vegetable intake is far below that recommended. Despite increased awareness of the importance of vegetable consumption for health, it remains challenging to improve children’s vegetable intake. Since food preferences are central to

  13. Add More Vegetables to Your Day: 10 Tips to Help You Eat More Vegetables (United States)

    ... sip on some vegetable soup Heat it and eat it. Try tomato, butternut squash, or garden vegetable soup. Look for reduced- or low-sodium soups. Make your own soups with a low-sodium broth and your favorite vegetables. 8 while you’re out If dinner is away from home, no need to worry. ...

  14. Hydrology and ecology of the Apalachicola River, Florida : a summary of the river quality assessment (United States)

    Elder, John F.; Flagg, Sherron D.; Mattraw, Harold C.


    During 1979-81, the U.S. Geological Survey conducted a large-scale study of the Apalachicola River in northwest Florida, the largest and one of the most economically important rivers in the State. Termed the Apalachicola River Quality Assessment, the study emphasized interrelations among hydrodynamics, the flood-plain forest, and the nutrient-detritus flow through the river system to the estuary. This report summarizes major findings of the study. Data on accumulation of toxic substances in sediments and benthic organisms in the river were also collected. Because of the multiple uses of the Apalachicola River system, there are many difficult management decisions. The river is a waterway for shipping; hence there is an economic incentive for modification to facilitate movement of barge traffic. Such modifications include the proposed construction of dams, levees, bend easings, and training dikes; ditching and draining in the flood plain; and dredging and snagging in the river channel. The river is also recognized as an important supplier of detritus, nutrients, and freshwater to the Apalachicola Bay, which maintains an economically important shellfish industry. The importance of this input to the bay creates an incentive to keep the river basin in a natural state. Other values, such as timber harvesting, recreation, sport hunting, nature appreciation, and wildlife habitat, add even more to the difficulty of selecting management strategies. Water and nutrient budgets based on data collected during the river assessment study indicate the relative importance of various inputs and outflows in the system. Waterflow is controlled primarily by rainfall in upstream watersheds and is not greatly affected by local precipitation, ground-water exchanges, or evapotranspiration in the basin. On an annual basis, the total nutrient inflow to the system is nearly equal in quantity to total outflow, but there is a difference between inflow and outflow in the chemical and physical

  15. Missouri River 1943 Compact Line (United States)

    Iowa State University GIS Support and Research Facility — Flood Control, Bank Stabilization and development of a navigational channel on the Missouri River had a great impact on the river and adjacent lands. The new...

  16. Haw River PFCs Data Set (United States)

    U.S. Environmental Protection Agency — PFAS concentrations in river and drinking water in and around the Haw River in North Carolina. This dataset is associated with the following publication: Sun, M., E....

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

    International Nuclear Information System (INIS)

    Jansson, Roland


    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

  18. Effects of Telecoupling on Global Vegetation Dynamics (United States)

    Viña, A.; Liu, J.


    With the ever increasing trend in telecoupling processes, such as international trade, all countries around the world are becoming more interdependent. However, the effects of this growing interdependence on vegetation (e.g., shifts in the geographic extent and distribution) remain unknown even though vegetation dynamics are crucially important for food production, carbon sequestration, provision of other ecosystem services, and biodiversity conservation. In this study we evaluate the effects of international trade on the spatio-temporal trajectories of vegetation at national and global scales, using vegetation index imagery collected over more than three decades by the Advanced Very High Resolution Radiometer (AVHRR) satellite sensor series together with concurrent national and international data on international trade (and its associated movement of people, goods, services and information). The spatio-temporal trajectories of vegetation are obtained using the scale of fluctuation technique, which is based on the decomposition of the AVHRR image time series to obtain information on its spatial dependence structure over time. Similar to the correlation length, the scale of fluctuation corresponds to the range over which fluctuations in the vegetation index are spatially correlated. Results indicate that global vegetation has changed drastically over the last three decades. These changes are not uniform across space, with hotspots in active trading countries. This study not only has direct implications for understanding global vegetation dynamics, but also sheds important insights on the complexity of human-nature interactions across telecoupled systems.

  19. Spectrophotometric Determination of Nitrate in Vegetables Using ...

    African Journals Online (AJOL)


    ABSTRACT: A rapid and sensitive spectrophotometric method for the determination of nitrate in vegetables is described. The method is based on the measurement of the absorbance of yellow sodium nitrophenoxide formed via the reaction of phenol with the vegetable-based nitrate in presence of sulphuric acid.

  20. Man-influenced vegetation of North Korea

    Czech Academy of Sciences Publication Activity Database

    Kolbek, Jiří; Jarolímek, I.


    Roč. 40, č. 1 (2008), s. 381-404 ISSN 0253-116X R&D Projects: GA ČR(CZ) GA206/05/0119 Institutional research plan: CEZ:AV0Z60050516 Keywords : vegetation classification * weed communities * man-depending vegetation Subject RIV: EF - Botanics

  1. Technical efficiency of irrigated vegetable production among ...

    African Journals Online (AJOL)

    This study was carried out to analyse the technical efficiency of irrigated vegetable production among smallholder farmers in the guinea savannah, Nigeria, and determine the cost and returns on irrigated vegetable production. Two-stage sampling technique was used, purposive selection of two states and three Local ...

  2. Measurement Of Technical Efficiency In Irrigated Vegetable ...

    African Journals Online (AJOL)

    This study measured technical efficiency and identified its determinants in irrigated vegetable production in Nasarawa State of Nigeria using a stochastic frontier model. A complete enumeration of 193 NADP-registered vegetable farmers was done. The predicted farm technical efficiency ranges from 25.94 to 96.24 per cent ...

  3. Gelation and interfacial behaviour of vegetable proteins

    NARCIS (Netherlands)

    Vliet, T. van; Martin, A.H.; Bos, M.A.


    Recent studies on gelation and interfacial properties of vegetable protiens are reviewed. Attention is focused on legume proteins, mainly soy proteins, and on wheat proteins. The rheological properteis of vegetable protein gels as a function of heating time or temperature is discussed as well as the

  4. Gelation and interfacial behaviour of vegetable proteins

    NARCIS (Netherlands)

    Vliet, van T.; Martin, A.H.; Bos, M.A.


    Recent studies on gelation and interfacial properties of vegetable proteins are reviewed. Attention is focused on legume proteins, mainly soy proteins, and on wheat proteins. The rheological properties of vegetable protein gels as a function of heating time or temperature is discussed as well as the

  5. Food design strategies to increase vegetable intake

    NARCIS (Netherlands)

    Oliviero, Teresa; Fogliano, Vincenzo


    Background: Public campaigns promoting consumption of fruits and vegetables had limited results as consumers habits are difficult to modify. The incorporation of fruits and vegetables into regularly eaten products is a food design strategy that leads to several advantages. Pasta is a staple food

  6. STOVE: Seed treatments for organic vegetable production

    NARCIS (Netherlands)

    Schmitt, A.; Jahn, M.; Kromphardt, C.; Krauthausen, H.J.; Roberts, S.J.; Wright, S.A.I.; Amein, T.; Forsberg, G.; Tinivella, F.; Gullino, M.L.; Wikström, M.; Wolf, van der J.M.; Groot, S.P.C.; Werner, S.; Koch, E.


    The aim of the EU-financed research project „STOVE“ (Seed Treatments for Organic Vegetable Production) is to evaluate different methods potentially suited for seed treatment of vegetables in organic farming regarding their efficacy, to optimise these methods, and where feasible to combine them with

  7. Natural Vegetation of the Flora area

    DEFF Research Database (Denmark)

    Sebsebe, Demissew; Friis, Ib


    A review article summarising the recent ideas about the natural vegetation in the area covered by the Flora of Ethiopia and Eritrea......A review article summarising the recent ideas about the natural vegetation in the area covered by the Flora of Ethiopia and Eritrea...

  8. Atlas of the potential vegetation of Ethiopia

    DEFF Research Database (Denmark)

    Friis, Ib; Demissew, Sebsebe; van Breugel, Paulo

    Based on many years of field work by the two senior authors (Ib Friis and Sebsebe Demissew) and with the application of GIS analyses (by P. van Breugel) 15 major vegetation types in Ethiopia are described and mapped. The book descibes the structure and floristic composition of the vegetation types...

  9. Use of Plastic Mulch for Vegetable Production


    Maughan, Tiffany; Drost, Dan


    Plastic mulches are used commercially for both vegetables and small fruit crops. Vegetable crops well suited for production with plastic mulch are typically high value row crops. This fact sheet describes the advantages, disadvantages, installation, and planting considerations. It includes sources for plastic and equipment.

  10. Classification and mapping of rangeland vegetation physiognomic ...

    African Journals Online (AJOL)

    Plot vegetation species growth form, cover and height data were collected from 450 sampling sites based on eight spectral strata generated using unsupervised image classification. Field data were grouped at four levels of seven, six, three and two vegetation physiognomic classes which were subjected to both ML and ...

  11. Effects of aquatic vegetation type on denitrification

    NARCIS (Netherlands)

    Veraart, A.J.; Bruijne, de W.J.J.; Peeters, E.T.H.M.; Klein, de J.J.M.; Scheffer, M.


    In a microcosm 15N enrichment experiment we tested the effect of floating vegetation (Lemna sp.) and submerged vegetation (Elodea nuttallii) on denitrification rates, and compared it to systems without macrophytes. Oxygen concentration, and thus photosynthesis, plays an important role in regulating

  12. Weed Identification and Control in Vegetable Crops. (United States)

    Ferretti, Peter A., Comp.

    This agriculture extension service publication from Pennsylvania State University examines weed control and identification in vegetable crops. Contents include: (1) Types of weeds; (2) Reducing losses caused by weeds, general control methods and home garden weed control; (3) How herbicides are used; (4) Specific weeds in vegetable plantings; and…

  13. Radiation processing of foods: fruits and vegetables

    International Nuclear Information System (INIS)

    Thomas, Paul


    Post-harvest irradiation of fruits and vegetables improves their shelf-life by: (1) delaying ripening and senescence of fruits, (2) controlling fungal diseases, (3) inhibiting sprouting, and (4) disinfestation. Nutritional and quality aspects of irradiated fruits and vegetables are discussed. Commercial prospects are briefly described. (M.G.B.)

  14. Modeling the location of the forest line in northeast European Russia with remotely sensed vegetation and GIS-based climate and terrain data

    DEFF Research Database (Denmark)

    Virtanen, Tarmo; Mikkola, Kari; Nikula, Ari


    GIS-based data sets were used to analyze the structure of the forest line at the landscape level in the lowlands of the Usa River Basin, in northeast European Russia. Vegetation zones in the area range from taiga in the south to forest-tundra and tundra in the north. We constructed logistic...

  15. Estrutura da vegetação em florestas de mangue do estuário do rio Paraíba do Sul, Estado do Rio de Janeiro, Brasil Vegetation structure of the mangrove forest at the estuary Paraíba do Sul river, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Elaine Bernini


    Full Text Available A estrutura da vegetação do manguezal do estuário do rio Paraíba do Sul foi analisada pelo método de parcelas, que foram distribuídas na franja e no interior da floresta em dois sítios de estudo. No geral, considerando-se os indivíduos > 1m alt., a altura média variou de 6,3 a 9,9m, o DAP médio de 7,44 a 13,4cm, a área basal média de 14,5 a 35,3m².ha-1 e a densidade média de 1.920 a 3.400 troncos.ha-1. Estes parâmetros estruturais não diferiram, significativamente, entre a franja e o interior da floresta, mas a contribuição de cada espécie variou entre as distintas zonas. Avicennia germinans (L. Stearn. foi a espécie dominante em área basal de indivíduos vivos (60%, seguida de Rhizophora mangle L. (25% e de Laguncularia racemosa (L. Gaertn. (15%. Os resultados obtidos demonstraram que a área de manguezal analisada apresenta melhor desenvolvimento estrutural quando comparada a outros manguezais do litoral fluminense, tais como os encontrados nas Baías de Guanabara e Sepetiba.A structural analysis of the mangrove forest at the Paraíba do Sul river estuary was performed using the stand method. The stands were demarcated in two points both at the forest edge and interior. The results indicate that average height varied from 6.3 to 9.9m; DBH varied from 7.44 to 13.4cm; average basal area varied from 14.5 to 35.3m².ha-1, and average density varied from 1,920 to 3,400 trunks.ha-1 (trees > 1m height. These structural parameters did not differ between the edge and the interior, but the contribution of each species varied between the zones. Avicennia germinans (L. Stearn. was the dominant species (60%, followed by Rhizophora mangle L. (25%, and Laguncularia racemosa (L. Gaertn. (15%. These results demonstrate that the mangroves forest at the Paraíba do Sul estuary has a better structural development than other mangrove sites found in the Rio de Janeiro State (e.g., those mangrove forests located at the Sepetiba and Guanabara

  16. Savannah River site environmental report for 1996

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.; Mamatey, A. [eds.


    The mission at the Savannah River Site (SRS) has changed from the production of nuclear weapons materials for national defense to the management of site-generated waste, restoration of the surrounding environment, and the development of industry in and around the site. However, SRS-through its prime operating contractor, Westinghouse Savannah River Company (WSRC)-continues to maintain a comprehensive environmental monitoring program. In 1996, effluent monitoring and environmental surveillance were conducted within a 31,000-square-mile area in and around SRS that includes neighboring cities, towns, and counties in Georgia and South Carolina and extends up to 100 miles from the site. Though the environmental monitoring program was streamlined in 1996-to improve its cost-effectiveness without compromising data quality or reducing its overall ability to produce critical information-thousands of samples of air, surface water, groundwater, food products, drinking water, wildlife, rainwater, soil, sediment, and vegetation were collected and analyzed for radioactive and nonradioactive contaminants.

  17. Frost risks in the Mantaro river basin

    Directory of Open Access Journals (Sweden)

    G. Trasmonte


    Full Text Available As part of the study on the Mantaro river basin's (central Andes of Perú current vulnerability to climate change, the temporal and spatial characteristics of frosts were analysed. These characteristics included intensity, frequency, duration, frost-free periods, area distribution and historical trends. Maps of frost risk were determined for the entire river basin, by means of mathematical algorithms and GIS (Geographic Information Systems tools, using minimum temperature – 1960 to 2002 period, geomorphology, slope, land-use, types of soils, vegetation and life zones, emphasizing the rainy season (September to April, when the impacts of frost on agriculture are most severe. We recognized four categories of frost risks: low, moderate, high and critical. The critical risks (with a very high probability of occurrence were related to high altitudes on the basin (altitudes higher than 3800 m a.s.l., while the low (or null probability of occurring risks were found in the lower zones (less than 2500 m a.s.l.. Because of the very intense agricultural activity and the high sensitivity of the main crops (Maize, potato, artichoke in the Mantaro valley (altitudes between 3100 and 3300 m a.s.l., moderate to high frost risks can be expected, with a low to moderate probability of occurrence. Another significant result was a positive trend of 8 days per decade in the number of frost days during the rainy season.

  18. Savannah River site environmental report for 1996

    International Nuclear Information System (INIS)

    Arnett, M.; Mamatey, A.


    The mission at the Savannah River Site (SRS) has changed from the production of nuclear weapons materials for national defense to the management of site-generated waste, restoration of the surrounding environment, and the development of industry in and around the site. However, SRS-through its prime operating contractor, Westinghouse Savannah River Company (WSRC)-continues to maintain a comprehensive environmental monitoring program. In 1996, effluent monitoring and environmental surveillance were conducted within a 31,000-square-mile area in and around SRS that includes neighboring cities, towns, and counties in Georgia and South Carolina and extends up to 100 miles from the site. Though the environmental monitoring program was streamlined in 1996-to improve its cost-effectiveness without compromising data quality or reducing its overall ability to produce critical information-thousands of samples of air, surface water, groundwater, food products, drinking water, wildlife, rainwater, soil, sediment, and vegetation were collected and analyzed for radioactive and nonradioactive contaminants

  19. Stochastic Modelling of River Geometry

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Schaarup-Jensen, K.


    Numerical hydrodynamic river models are used in a large number of applications to estimate critical events for rivers. These estimates are subject to a number of uncertainties. In this paper, the problem to evaluate these estimates using probabilistic methods is considered. Stochastic models for ...... for river geometries are formulated and a coupling between hydraulic computational methods and numerical reliability methods is presented....

  20. The Gediz River fluvial archive

    NARCIS (Netherlands)

    Maddy, D.; Veldkamp, A.; Demir, T.; Gorp, van W.; Wijbrans, J.R.; Hinsbergen, van D.J.J.; Dekkers, M.J.; Schreve, D.; Schoorl, J.M.; Scaife, R.


    The Gediz River, one of the principal rivers of Western Anatolia, has an extensive Pleistocene fluvial archive that potentially offers a unique window into fluvial system behaviour on the western margins of Asia during the Quaternary. In this paper we review our work on the Quaternary Gediz River