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Aerul ?i Apa : Componente ale Mediului , 2011,
Abstract: Issues regarding the flood impact on the herpetofauna habitats from riparian areas. Flood risk management measures have a major effect on biodiversity conservation of wetlands and riparians areas. Therefore, understanding the need for cooperation and collaboration of all stakeholders (governmental and non-government) in planning and flood risk management in line with European requirements, respectively Habitat directive in association with the domestic law.This paper aims to highlight the importance of riparian areas developed at the interface between terrestrial and aquatic systems, who besides his role in the delineation of ecosystems and the complex functions they perform: loading / discharging groundwater, flood control,protection against erosion, retention of nutrients and export of biomass, protection, microclimate stabilization has a major role in the conservation of specific habitats of these environments, being the least affected by anthropogenic activity,so that relations found between the "living world" and natural support are the most solid.Because the decline of amphibians has direct and visible effects on ecosystem structure, there is an acute need for optimization of the local reproductive populations of amphibians is required for appropriate management of habitats such as breeding and feeding habitats. Only protection of aquatic habitats (breeding) has little value if terrestrial habitats used for feeding amphibians are destroyed.
Small Mammal Habitat Use within Restored Riparian Habitats Adjacent to Channelized Streams in Mississippi  [PDF]
Peter C. Smiley Jr., Charles M. Cooper
Journal of Environmental Protection (JEP) , 2013, DOI: 10.4236/jep.2013.411149

Riparian zones of channelized agricultural streams in northwestern Mississippi typically consist of narrow vegetative corridors low in habitat diversity and lacking riparian wetlands. Land clearing practices and stream channelization have led to the development of gully erosion and further fragmentation of these degraded riparian zones. Currently, installation of a gully erosion control structure (drop pipe) at the riparian zone-agricultural field interface leads to the incidental establishment of four riparian habitat types that differ in habitat area, vegetative structure, and pool size. Small mammals were sampled within four sites of each habitat type from June 1994 to July 1995. Small mammal diversity, abundance, and hispid cotton rat (Sigmodon hispidus) weight were the least within smallest Type I habitats with the least vegetative structural diversity and were the greatest within the larger Type II, III, or IV habitats having greater vegetative structural diversity and pool size. Small mammal diversity and abundance were the least in the summer 1994, increased in the fall 1994, and then declined later in our study. Hispid cotton rat abundance was the least in summer 1994, winter 1994, and spring 1995 and was the greatest in fall 1994 and summer 1995. Our results suggest that modifying the drop pipe installation design to facilitate the development of larger riparian habitats with greater vegetative structural diversity will provide the greatest benefits for small mammals.

Structure and Dynamics of Korean Red Pine Stands Established as Riparian Vegetation at the Tsang Stream in Mt. Seorak National Park, Eastern Korea  [cached]
Chun, Young-Moon,Sung-Ae Park,Chang-Seok Lee
Journal of Ecology and Field Biology , 2007,
Abstract: The structure and dynamics of Korean red pine stands established in the riparian zone werestudied in the Tsang stream in Mt. Seorak National Park, in east-central Korea. Pine stands were classified intofour successional stages, the initial, establishing, competitive, and stabilizing stages, based on the age distributionof a dominant tree, Pinus densiflora, the vegetation stratification, and the microtopography of the riverineenvironment. The stages usually corresponded to disturbance frequencies, depending on the horizontal andvertical distances from the watercourse. Stands of the initial and establishing stages lacked tree or subtreelayers, or both. As stands progressed through the developmental stages, soil particle size became finer andmoisture retention capacity was improved. The stand ordination reflected the developmental stage, and thespecies ordination differentiated species specializing in relatively dry and wet habitats. The results of the analysisof vegetation dynamics provided ecological information which will be useful for understanding the developmentalprocesses of vegetation established in riparian zones. Species diversity indices usually increased across developmentalstages, following the typical pattern for successional processes. We discuss the importance and necessityof riparian vegetation in Korea, where most riparian forests have disappeared due to excessive human land use.
Nitrogen uptake in riparian plant communities across a sharp ecological boundary of salmon density
DD Mathewson, MD Hocking, TE Reimchen
BMC Ecology , 2003, DOI: 10.1186/1472-6785-3-4
Abstract: δ15N and %N in foliage, and %cover of soil nitrogen indicators differed across the waterfall barrier to salmon at each watershed. δ15N values were enriched by 1.4‰ to 9.0‰ below the falls depending on species and watershed, providing a relative contribution of marine-derived nitrogen (MDN) to vegetation of 10% to 60%. %N in foliar tissues was slightly higher below the falls, with the majority of variance occurring between vegetation species. Community structure also differed with higher incidence of nitrogen-rich soil indicator species below the waterfalls.Measures of δ15N, %N and vegetation cover indicate a consistent difference in the riparian community across a sharp ecological boundary of salmon density. The additional N source that salmon provide to nitrogen-limited habitats appears to have significant impacts on the N budget of riparian vegetation, which may increase primary productivity, and result in community shifts between sites with and without salmon access. This, in turn, may have cascading ecosystem effects in forests adjacent to salmon streams.The cycling of nutrients between Pacific salmon (Oncorhynchus spp.) and coastal watersheds has gained much attention in the past decade [1,2]. As well as an important contribution to estuarine and stream productivity [3], salmon nutrients are transferred from streams into adjacent forests by bears and wolves where remnants of the partially-consumed carcasses are used by a diverse assemblage of vertebrate and invertebrate scavengers [4-7]. Coastal forests of western North America tend to be nitrogen-limited and there is recent evidence that vegetation in the narrow riparian zone adjacent to the streams also sequesters these marine-derived nutrients [8-12]. The contribution of salmon tissues to total nitrogen concentration in these riparian plants is variable but values from 10% to 40% have been reported [9,11,12].Nitrogen deficiencies are known to limit plant growth [13-15] while additions of nitrogen, such as th
How Spatial Variation in Areal Extent and Configuration of Labile Vegetation States Affect the Riparian Bird Community in Arctic Tundra  [PDF]
John-André Henden, Nigel G. Yoccoz, Rolf A. Ims, Knut Langeland
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0063312
Abstract: The Arctic tundra is currently experiencing an unprecedented combination of climate change, change in grazing pressure by large herbivores and growing human activity. Thickets of tall shrubs represent a conspicuous vegetation state in northern and temperate ecosystems, where it serves important ecological functions, including habitat for wildlife. Thickets are however labile, as tall shrubs respond rapidly to both abiotic and biotic environmental drivers. Our aim was to assess how large-scale spatial variation in willow thicket areal extent, configuration and habitat structure affected bird abundance, occupancy rates and species richness so as to provide an empirical basis for predicting the outcome of environmental change for riparian tundra bird communities. Based on a 4-year count data series, obtained through a large-scale study design in low arctic tundra in northern Norway, statistical hierarchical community models were deployed to assess relations between habitat configuration and bird species occupancy and community richness. We found that species abundance, occupancy and richness were greatly affected by willow areal extent and configuration, habitat features likely to be affected by intense ungulate browsing as well as climate warming. In sum, total species richness was maximized in large and tall willow patches of small to intermediate degree of fragmentation. These community effects were mainly driven by responses in the occupancy rates of species depending on tall willows for foraging and breeding, while species favouring other vegetation states were not affected. In light of the predicted climate driven willow shrub encroachment in riparian tundra habitats, our study predicts that many bird species would increase in abundance, and that the bird community as a whole could become enriched. Conversely, in tundra regions where overabundance of large herbivores leads to decreased areal extent, reduced height and increased fragmentation of willow thickets, bird community richness and species-specific abundance are likely to be significantly reduced.
Influence of the riparian zone phytophysiognomies on the longitudinal distribution of fishes: evidence from a Brazilian savanna stream
Teresa, Fabrício Barreto;Romero, Renato de Mei;
Neotropical Ichthyology , 2010, DOI: 10.1590/S1679-62252010000100019
Abstract: the structure and composition of a fish community in a tributary stream of the aquidauana river, located in the plateau region of the paraguay river basin, central west brazil are described, with special attention to the differential effects of the phytophysiognomies of the cerrado (a tropical savanna), which are predominant in riparian zones all along their longitudinal gradient. a total of 1,166 individuals belonging to 44 species were captured. similarity analyses of composition and abundance showed two groups: upstream reaches (r1 and r2) and downstream reaches (r3, r4 and r5), which presented 85.8% of the average dissimilarity. although physical habitat and physicochemical descriptors varied along the longitudinal gradient of the correntes stream, shoreline vegetation was the most important environmental feature predicting fish structure and composition. the mantel test revealed a correlation between shoreline vegetation structure and fish composition and quantitative structure of the fish community (r > 0.65; p < 0.04). this relationship is driven by the prevalence of species occupying microhabitats associated with shoreline vegetation in contact with water in upstream reaches. structural differences in shoreline vegetation along the longitudinal gradient correspond to the phytophysiognomic dichotomy observed in the correntes stream, where riparian vegetation is made up of wet grassland upstream and of gallery forest downstream; this reinforces the importance of the phytophysiognomic heterogeneity of the cerrado in maintaining ichthyofauna diversity.
Multiple scale protection planning of waterbird habitats in Xi′an Chanba River wetland

ZHAO Zhen-Bin,ZHAO Hong-Feng,TIAN Xian-Hua,YAN Jun-Ping,

生态学报 , 2008,
Abstract: Urban wetland and wildlife diversity protection is the important task of urban ecological construction. With the case study of Chan-ba River wetland in Xian City, the issues of urban waterbird habitat protection planning are discussed in this paper. By field investigation, the study area is found feeding 20 species, belonging to 8 orders and 12 families, showing a high birds diversity level. Some indigenous plant species and different habitat types are also found in the study area, with high value in sight of urban nature protection. The protection of the waterbird habitats in Chanba river wetland should be based on the relating theories of landscape ecology, conservation biology, and metapopulation, and carried on from different spatial scale. The main approaches include: habitat network construction, small habitat design, water depth control, and land use pattern optimization in riparian zone, plant community organization.
Soil biological evaluation on ecological remedy of damaged riparian.

ZHANG Yu-bo,YANG Hai-jun,WANG De-li,XIAO Zhi-jian,HAN Ji-yue,

应用生态学报 , 2008,
Abstract: In order to explore the theory and technique about the restoration of damaged riparian ecosystem, this paper evaluated the remedy effect of artificial spotted habitats that have been built for four years on the damaged riparian ecosystem based on soil biological principles. The results showed that in restored area, the quantities of various soil microbial species were significantly higher, and the species, quantity, and biodiversity of soil animal as well as the contents of soil organic matter, nitrogen, phosphorus, and potassium were all higher than those in un-restored area. After successful restoration, the soil conditions in damaged riparian were significantly improved, which resulted in an increase in soil biodiversity and enhanced the stability of this ecosystem. The remedy technique for the damaged riparian by using artificially spotted habitats not only consumed less cost, but also exhibited great ecological, landscape, and social values, providing a new model for the ecological reconstruction of damaged concrete riparian and the approximately natural remediation of damaged riparian.

PAN Xiao-Yun,GENG Yu-Peng,ZHANG Wen-Ju,LI Bo,CHEN Jia-Kuan,

植物生态学报 , 2006,
Abstract: Background and Aims Biological invasions by non-native species have become a major environmental problem and a focus of ecological research. Relatively few studies have focused on invasibility and invasivness among microhabitats within communities. We compared the abundance and performance of non-native Alternanthera philoxeroides (alligator weed) and its co-occurring native congener,Alternanthera sessilis (sessile joyweed),in a wetland community along a riparian zone in southeast China to test the hypotheses that: 1) the degree of invasion differs between different types of microhabitats within the community; 2) microhabitat types that differ in invasion also differ in soil resource availability or in sediment characteristics likely to affect resource availability; and 3) phenotypic plasticity must have played a key role in adaptation to diverse habitats for A. philoxeroides because of its extremely low genetic diversity throughout China. Methods Field surveys of natural distribution and performance of the two varieties on adjacent and contrasting microhabitat types (abandoned field,swamp,marsh dunes and gravel dunes) along a riparian zone were conducted in the autumn of 2003. Key Results Soil organic matter,total N,available P and K were significantly higher and pH was lower in dryland and swamp than in dunes. Total vegetation coverage was significantly higher in dryland and swamp than in dunes. The relative coverage of A. philoxeroides was much higher than that of A. sessilis in more productive habitats (i.e. dry land and swamps),but this pattern reversed in less productive habitats (i.e. marsh and gravel dunes). A. philoxeroides showed greater morphological plasticity in response to habitat variation. Especially,the CV (coefficient of variation) of leaf area and branch angle in A. philoxeroides was 70 and 83 times greater than those in A. sessilis,respectively. Several morphological traits related to light foraging increased significantly from marsh and gravel dunes to more productive habitats (dry land and swamps). These traits included stem length,internode length,the number of nodes,and leaf length and width. Moreover,the leaf-bearing stems grew more vertically in dry land and swamps. Meanwhile,these traits in A. sessilis had no obvious variations among microhabitats. Conclusions These results suggest that high plasticity in vertical growth and occupancy of soil microhabitat of rich nutrient resources may facilitate the invasions of A. philoxeroides.
Population Size and Migration of Anopheles gambiae in the Bancoumana Region of Mali and Their Significance for Efficient Vector Control  [PDF]
Ibrahima Baber,Moussa Keita,Nafomon Sogoba,Mamadou Konate,M'Bouye Diallo,Seydou Doumbia,Sékou F. Traoré,José M. C. Ribeiro,Nicholas C. Manoukis
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0010270
Abstract: We present results of two intensive mark-release-recapture surveys conducted during the wet and dry seasons of 2008 in the villages of Fourda and Kenieroba, Mali. The former is a small fishing village by the Niger River with a moderate to high densities of Anopheles gambiae Giles s.s. (Diptera: Culicidae) throughout the year, while the latter is a large agricultural community 2 km inland that experiences strong seasonal fluctuation in An. gambiae densities. We estimate the population size of female An. gambiae in Fourda to be in less than 3,000 during the dry season. We found evidence of large population size and migration from Fourda in Kenieroba during the wet season, but very low numbers and no sign of migrants during the dry season. We suggest that malaria vector control measures aimed at adult mosquitoes might be made more efficient in this region and other seasonal riparian habitats by targeting disruption of mosquito populations by the river during the dry season. This would decrease the size of an already small population, and would be likely to delay the explosive growth in vector numbers in the larger inland villages as rainfall increases.
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