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Standing Water (standing + water)
Selected AbstractsDoes habitat use explain large scale species richness patterns of aquatic beetles in Europe?ECOGRAPHY, Issue 2 2003Ignacio Ribera Regularities in species richness are widely observed but controversy continues over its mechanistic explanation. Because richness patterns are usually a compound measure derived from taxonomically diverse species with different ecological requirements, these analyses may confound diverse causes of species numbers. Here we investigate species richness in the aquatic beetle fauna of Europe, separating major taxonomic groups and two major ecological types, species occurring in standing and running water bodies. We collated species distributions for 800+ species of water beetles in 15 regions across western Europe. Species number in any of these regions was related to three variables: total area size, geographic connectedness of the area, and latitude. Pooled species numbers were accurately predicted, but correlations were different for species associated with either running or standing water. The former were mostly correlated with latitude, while the latter were only correlated with the measure of connectedness or with area size. These differences were generally also observed in each of the four phylogenetically independent lineages of aquatic Coleoptera when analysed separately. We propose that effects of habitat, in this case possibly mediated by different long term persistence of running and standing water bodies, impose constraints at the population or local level which, if effective over larger temporal and spatial scales, determine global patterns of species richness. [source] A 3.5 ka record of paleoenvironments and human occupation at Angkor Borei, Mekong Delta, southern CambodiaGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 3 2003Paul Bishop Microfossil and sedimentological data from a 3.1 m core extracted from a reservoir (baray) at the ancient Cambodian settlement of Angkor Borei in the Mekong Delta have provided a continuous record of sedimentation and paleoenvironments dating from about 2000 cal yr B.C. Palynological data indicate that for much of the cal. 1st and 2nd millennia B.C. mangroves dominated the regional vegetation, while extensively and regularly burnt grasslands dominated the local vegetation. Turbid, nutrient-rich standing water characterized the core locality, perhaps suggesting a connection with rivers in the area. An abrupt change during the cal. 5th to 6th centuries A.D. involved a dramatic reduction in grasslands and the expansion of secondary forest or re-growth taxa. These changes are synchronous with an abrupt decline in the concentration of microscopic charcoal particles in the sediments, and the colonization of the core locality by swamp forest plants. These changes are taken to indicate a shift in land-use strategies or, possibly, a period of land abandonment. The age for the construction of the baray is interpreted to be in the 17th,19th centuries, but this dating remains speculative. Construction of the Angkor Borei baray exploited a preexisting body of standing water, so its construction was fundamentally different from the methods used at the Angkorian capital in northern Cambodia. © 2003 Wiley Periodicals, Inc. [source] A beetle's eye view of London from the Mesolithic to Late Bronze AgeGEOLOGICAL JOURNAL, Issue 5 2009Scott A. Elias The aim of this paper is to reconstruct the environmental history of the London region, based on changes in beetle faunal assemblages from the Mesolithic to Late Bronze Age. Eight sites were studied, all but one of which are within 2,km of the modern course of the Thames. The sites produced 128 faunal assemblages that yielded 218 identified species in 41 families of Coleoptera (beetles). Beetle faunas of Mesolithic age indicate extensive wetlands near the Thames, bordered by rich deciduous woodlands. The proportion of woodland species declined in the Neolithic, apparently because of the expansion of wetlands, rather than because of human activities. The Early Bronze Age faunas contained a greater proportion of coniferous woodland and aquatic (standing water) species. An increase in the dung beetle fauna indicates the presence of sheep, cattle and horses, and various beetles associated with crop lands demonstrate the local rise of agriculture, albeit several centuries after the beginnings of farming in other regions of Britain. Late Bronze Age faunas show the continued development of agriculture and animal husbandry along the lower Thames. About 33% of the total identified beetle fauna from the London area sites have limited modern distributions or are extinct in the U.K. Some of these species are associated with the dead wood found in primeval forests; others are wetland species whose habitat has been severely reduced in recent centuries. The third group is stream-dwelling beetles that require clean, clear waters and river bottoms. Copyright © 2009 John Wiley & Sons, Ltd. [source] Scared fish get lazy, and lazy fish get fatJOURNAL OF ANIMAL ECOLOGY, Issue 4 2009Frank Johansson Summary 1Many biological textbooks present predator-induced morphological changes in prey species as an example of an adaptive response, because the morphological change is associated with lower predation risk. Here we show that the adaptive morphological response observed in many systems may actually be an indirect effect of decreased activity , which reduces the predation risk , rather than a direct adaptive response. 2One of the classical examples comes from crucian carp, where the presence of pike leads to a deeper body. We manipulated pike cues (presence and absence) and water current (standing and running water) and found that both standing water and pike cues similarly and independently induced a deeper body. 3Since the presence of pike cues as well as standing water might be associated with low swimming activity, we suggest that the presence of pike causes a reduction in activity (antipredator behaviour). Reduced activity subsequently induces a deeper body, possibly because the energy saved is allocated to a higher growth rate. 4Our result suggests that even if morphological change is adaptive, it might be induced indirectly via activity. This important conceptual difference may be similar in many other systems. [source] DEVELOPMENT AND APPLICATION OF A SPATIAL HYDROLOGY MODEL OF OKEFENOKEE SWAMP, GEORGIA,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 4 2001Cynthia S. Loftin ABSTRACT: The model described herein was used to assess effects of the Suwannee River sill (a low earthen dam constructed to impound the Suwannee River within the Okefenokee National Wildlife Refuge to eliminate wildfires) on the hydrologic environment of Okefenokee Swamp, Georgia. Developed with Arc/Info Macro Language routines in the GRID environment, the model distributes water in the swamp landscape using precipitation, inflow, evapotranspiration, outflow, and standing water. Water movement direction and rate are determined by the neighborhood topographic gradient, determined using survey grade Global Positioning Systems technology. Model data include flow rates from USGS monitored gauges, precipitation volumes and water levels measured within the swamp, and estimated evapotranspiration volumes spatially modified by vegetation type. Model output in semi-monthly time steps includes water depth, water surface elevation above mean sea level, and movement direction and volume. Model simulations indicate the sill impoundment affects 18 percent of the swamp during high water conditions when wildfires are scarce and has minimal spatial effect (increasing hydroperiods in less than 5 percent of the swamp) during low water and drought conditions when fire occurrence is high but precipitation and inflow volumes are limited. [source] A seasonal survey of surface water habitats within the River Spey basin, Scotland: major nutrient propertiesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2007B.O.L. Demars Abstract 1.Current monitoring strategies of governmental organizations tend to be focused on relatively large flowing and standing waters, and until recently those polluted by point sources. Consequently areas of high conservation interest tend to be understudied, and defining reference conditions, as required by current legislation, is difficult to achieve. 2.In order to address this imbalance, water samples have been collected and analysed once in each of four seasons during 2003 from 72 locations within a 100 km2 area of the oligotrophic River Spey catchment in NE Scotland. The sampling design included examples of running water (headwater streams and the main rivers) and standing water (lochs, lochans, pools, ditches, backwaters, bogs). Altitude ranged from 220 to 980 m and incorporated a climatic regime from cool temperate to sub-alpine. Each sampling campaign targeted low-flow conditions to evaluate steady-state nutrient concentrations. 3.Concentrations of the major soluble nutrients nitrogen and phosphorus demonstrated high spatial and temporal variability, with soluble organic and molybdate unreactive forms generally being dominant. Concentrations of ammonium-N, nitrate-N and soluble reactive phosphorus were extremely small, with 50% of samples falling below 8, 5 and 1 µg L,1, respectively, during spring and summer. 4.Sampling sites were grouped either by water-body type or by the properties of their immediate biophysical zone. Together these two groupings explained 33,38% of the variance in water chemistry. Certain changes were detectable across most habitats and biophysical zones. 5.A decline in the concentration of nitrate that occurred in reaches downstream from certain headwater streams draining the mountain areas indicated the potential for its within-stream utilization. Inorganic N dynamics differed between small streams and large rivers. 6.Landscape-scale patterns were recorded in spring and summer nutrient availability with inorganic N and P thresholds (arbitrarily defined) of 10 and 1 µg L,1, respectively. Copyright © 2006 John Wiley & Sons, Ltd. [source] The development of bird indicators for British fresh waters and wetlandsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue S1 2010Mark Everard Abstract 1.Population trends of breeding birds in freshwater habitats generated from long-term monitoring in the UK provide biodiversity indicators for some wetland habitats. 2.Bird species were assigned to target wetland habitats based on evidence of their association and data availability. Species trends for each habitat were then modelled using a range of survey data from BTO schemes including the Common Bird Census, Breeding Bird Survey, Waterways Bird Survey and Waterways Breeding Bird Survey. 3.Smoothed population trends for the selected species were combined to produce a composite indicator for birds of selected waterways and wetland habitats for England. This forms one of the three strands of a new aggregate bird indicator in the UK. 4.These indicators show generally that breeding bird species associated with slow-moving waterways and standing waters have increased over the past 30 years. Over the same period, species associated with fast-flowing waters show modest declines, species associated with reed habitats have declined and recovered, while species associated with wet grasslands, including marshes, have declined. 5.Further monitoring and exploration of the relationship between these indicators is needed to improve confidence in species trends and identifying potential drivers of change in freshwater and wetland habitats. Copyright © 2009 John Wiley & Sons, Ltd. [source] A seasonal survey of surface water habitats within the River Spey basin, Scotland: major nutrient propertiesAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2007B.O.L. Demars Abstract 1.Current monitoring strategies of governmental organizations tend to be focused on relatively large flowing and standing waters, and until recently those polluted by point sources. Consequently areas of high conservation interest tend to be understudied, and defining reference conditions, as required by current legislation, is difficult to achieve. 2.In order to address this imbalance, water samples have been collected and analysed once in each of four seasons during 2003 from 72 locations within a 100 km2 area of the oligotrophic River Spey catchment in NE Scotland. The sampling design included examples of running water (headwater streams and the main rivers) and standing water (lochs, lochans, pools, ditches, backwaters, bogs). Altitude ranged from 220 to 980 m and incorporated a climatic regime from cool temperate to sub-alpine. Each sampling campaign targeted low-flow conditions to evaluate steady-state nutrient concentrations. 3.Concentrations of the major soluble nutrients nitrogen and phosphorus demonstrated high spatial and temporal variability, with soluble organic and molybdate unreactive forms generally being dominant. Concentrations of ammonium-N, nitrate-N and soluble reactive phosphorus were extremely small, with 50% of samples falling below 8, 5 and 1 µg L,1, respectively, during spring and summer. 4.Sampling sites were grouped either by water-body type or by the properties of their immediate biophysical zone. Together these two groupings explained 33,38% of the variance in water chemistry. Certain changes were detectable across most habitats and biophysical zones. 5.A decline in the concentration of nitrate that occurred in reaches downstream from certain headwater streams draining the mountain areas indicated the potential for its within-stream utilization. Inorganic N dynamics differed between small streams and large rivers. 6.Landscape-scale patterns were recorded in spring and summer nutrient availability with inorganic N and P thresholds (arbitrarily defined) of 10 and 1 µg L,1, respectively. Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||