共查询到20条相似文献,搜索用时 31 毫秒
1.
Stanley I. Dodson William R. Everhart Andrew K. Jandl Sara J. Krauskopf 《Hydrobiologia》2007,579(1):393-399
Results of a field survey of southern Wisconsin shallow lakes suggested that watershed (catchment basin) land use has a significant and adverse effect on zooplankton species richness. Zooplankton communities in lakes with no riparian buffer zone, in agriculture-dominated watersheds, contained about half as many species as lakes in least-impact watersheds. In that study, the age of the lake was not taken into account. It is possible that agricultural lakes, often artificial, were so recently-constructed that they had not yet accumulated the equilibrium number of species characteristic of older lakes. In other words, it is possible that the interpretation of the results of the previous study is fatally flawed, if the results were an artifact of lake age, rather than an effect of land use. The major aim of this current study was to determine the ages of agricultural lakes and of lakes in least-impact watersheds, to test for an effect of lake age on zooplankton species richness, using the same sites from the previous study. We used an anova approach to test the null hypothesis that two factors, watershed land use and lake age, had no systematic effect on zooplankton species richness. We determined the age of 35 shallow lakes, using aerial photos, satellite images, and interviews of resource managers and land owners. We identified five artificial agricultural sites and five artificial sites in least-impact prairie watersheds. The artificial sites in this study ranged from 3 to 37 years in age, while natural lakes dated from the melting of the last glacier, about 9500 years ago. Our results suggest, that because artificial lake made up only about a third of the sites, and for the range of lake age and watershed land use, lake age did not have a significant effect on zooplankton species richness, while land use had a highly significant adverse effect. These results pose a larger question for future research. Namely, how quickly do newly-constructed lakes attain the equilibrium number of species seen in the previous study, and what is the quantitative relationship between lake age and zooplankton richness? 相似文献
2.
Nutrient loading to lakes depends on both the availability of nutrients in a watershed and their potential for movement to
a lake. Many studies have demonstrated that variation in watershed land use can translate to differences in lake water quality
by affecting nutrient availability. There have been few attempts, however, to understand how loading to surface waters is
affected by land use when there are differences in watershed transport capacity. We compared the relationship between land
use/cover and lake nutrients in lakes draining watersheds that exhibited high and low transport capacity using a 5 year (2001–2005)
dataset describing the chemistry of 101 lakes and reservoirs in a region of intensive agriculture. We measured watershed transport
capacity by compositing the hydrologic, geologic, and topographic variables correlated with interannual variability in lake
total nitrogen (TN) or phosphorus (TP) because the hydrologic permeability of watersheds amplifies downstream responses to
rainfall events. Factors describing watershed transport capacity differed for TN and TP, consistent with differences in nutrient
mobility and biogeochemistry. Partial least squares regression revealed that watershed transport capacity influenced the nature
of the association between land use/cover and lake chemistry. In watersheds with low transport capacity, in-lake processes
and near-shore land use/cover tended to be more influential, whereas, in watersheds with high transport capacity, land use/cover
across the entire watershed was important for explaining lake chemistry. Thus, although land use is a key driver of nutrient
loading to lakes, the extent to which it influences water quality can vary with watershed transport capacity.
JMF conceived the study and analyzed the data. JAD collected the data. JMF and JAD wrote the paper. 相似文献
3.
Matina Katsiapi Antonios D. Mazaris Evangelia Charalampous Maria Moustaka-Gouni 《Hydrobiologia》2012,698(1):121-131
The potential importance of watershed land use types, lake/watershed morphometry/topography and geographic distance as drivers of phytoplankton community composition was evaluated by using data collected from 18 freshwaters (lakes and reservoirs) distributed around Greece. In all freshwaters, phytoplankton species composition showed a strong correlation with the composition of land uses within their watersheds but no correlation with morphometry/topography and geographic distance. Cyanobacteria were found to be associated with artificial and agricultural land use types. Chrysophytes were closely associated to forested areas whereas euglenophytes to industrial, commercial, and transport units. Phytoplankton total biomass was significantly higher in freshwaters with a cover of agricultural and artificial land use >30% in their watersheds. This rather low threshold of agricultural and artificial land use cover might be indicative of the higher sensitivity of Mediterranean freshwaters to eutrophication process. Analysis performed separately for lakes and reservoirs revealed some diverse patterns with lake morphometric/topographic variables significantly affecting similarity in species occurrence. The results demonstrate that land use types reflecting anthropogenic pressures could act as critical drivers explaining phytoplankton structure. Our research suggests that Mediterranean freshwaters could be highly sensitive to land use types within their watersheds, thus landscape structure and configuration should be taken into account toward effective conservation and management plans. 相似文献
4.
《Harmful algae》2014
A statistically significant association was found between the concentration of total microcystin, a common class of cyanotoxins, in surface waters of lakes and reservoirs in the continental U.S. with watershed land use using data from 1156 water bodies sampled between May and October 2007 as part of the USEPA National Lakes Assessment. Nearly two thirds (65.8%) of the samples with microcystin concentrations ≥1.0 μg/L (n = 126) were limited to three nutrient and water quality-based ecoregions (Corn Belt and Northern Great Plains, Mostly Glaciated Dairy Region, South Central Cultivated Great Plains) in watersheds with strong agricultural influence. canonical correlation analysis (CCA) indicated that both microcystin concentrations and cyanobacteria abundance were positively correlated with total nitrogen, dissolved organic carbon, and temperature; correlations with total phosphorus and water clarity were not as strong. This study supports a number of regional lake studies that suggest that land use practices are related to cyanobacteria abundance, and extends the potential impacts of agricultural land use in watersheds to include the production of cyanotoxins in lakes. 相似文献
5.
Stormwater ponds are increasingly common aquatic habitats whose biotic communities are largely unexplored. As anthropogenic
development continues to alter the landscape, watershed land use is gaining recognition for its potential to predict species
compositions in aquatic systems. This study reports species composition of five aquatic hemipteran families (Notonectidae,
Corixidae, Belostomatidae, Nepidae, Pleidae) in 28 permanent, artificial stormwater ponds in watersheds with different land
covers and associated contaminant input. We hypothesized that land cover variables would be significant drivers of aquatic
hemipteran community structure in ponds, and that ponds with a high percentage of agricultural and lawn cover in the watershed
would be characterized by the absence of species intolerant of the chemical, physical, and ultimately biotic changes associated
with these watersheds. Non-metric multi-dimensional scaling (NMS) was used to identify dominant gradients of species composition
and environmental variables. Pond morphology variables, watershed lawn, watershed agriculture, and predatory fish abundance
were each found to have statistically significant correlations with hemipteran community structure. The abundance of Notonecta undulata, the species responsible for creating the largest (ranked) distance in species structure among ponds, was positively correlated
with shallow, fishless ponds and independent of land use variables. The abundances of four species of corixids were negatively
correlated with watershed agriculture, and hemipteran richness was positively correlated with watershed lawn and negatively
correlated with pond surface area. Heirarchical cluster analysis revealed non-random hemipteran species assemblages in which
congeneric corixid species tended to co-occur, contradicting traditional niche theory. Since artificial stormwater ponds are
chemically different from natural-pond habitat and rapidly increasing in number, knowledge of which insect species are capable
of thriving in this environment and their relationship to land use in the watershed is of both environmental and evolutionary
interest.
Handling editor: D. Dudgeon 相似文献
6.
Biological invasion by a benthivorous fish reduced the cover and species richness of aquatic plants in most lakes of a large North American ecoregion 总被引:1,自引:0,他引:1
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Przemyslaw G. Bajer Marcus W. Beck Timothy K. Cross Justine D. Koch William M. Bartodziej Peter W. Sorensen 《Global Change Biology》2016,22(12):3937-3947
Biological invasions are projected to be the main driver of biodiversity and ecosystem function loss in lakes in the 21st century. However, the extent of these future losses is difficult to quantify because most invasions are recent and confounded by other stressors. In this study, we quantified the outcome of a century‐old invasion, the introduction of common carp to North America, to illustrate potential consequences of introducing non‐native ecosystem engineers to lakes worldwide. We used the decline in aquatic plant richness and cover as an index of ecological impact across three ecoregions: Great Plains, Eastern Temperate Forests and Northern Forests. Using whole‐lake manipulations, we demonstrated that both submersed plant cover and richness declined exponentially as carp biomass increased such that plant cover was reduced to <10% and species richness was halved in lakes in which carp biomass exceeded 190 kg ha?1. Using catch rates amassed from 2000+ lakes, we showed that carp exceeded this biomass level in 70.6% of Great Plains lakes and 23.3% of Eastern Temperate Forests lakes, but 0% of Northern Forests lakes. Using model selection analysis, we showed that carp was a key driver of plant species richness along with Secchi depth, lake area and human development of lake watersheds. Model parameters showed that carp reduced species richness to a similar degree across lakes of various Secchi depths and surface areas. In regions dominated by carp (e.g., Great Plains), carp had a stronger impact on plant richness than human watershed development. Overall, our analysis shows that the introduction of common carp played a key role in driving a severe reduction in plant cover and richness in a majority of Great Plains lakes and a large portion of Eastern Temperate Forests lakes in North America. 相似文献
7.
Robert A. Zampella John F. Bunnell Kim J. Laidig Nicholas A. Procopio 《Ecological Indicators》2010,10(2):303-310
The establishment of introduced species in aquatic and wetland habitats is often associated with human-related environmental degradation. In the blackwater streams of the New Jersey Pinelands, the presence of nonnative species drives the relationship between community composition and watershed disturbance associated with developed land and upland agriculture. Most Pinelands lakes are shallow, artificial stream impoundments. In this study, we determined if land-use gradients or thresholds were associated with the presence of nonnative-herbaceous-plant, woody-plant, fish, and anuran species in 30 Pinelands stream impoundments. Correlation and regression analyses indicated that the response of all four taxonomic groups to watershed disturbance was an increase in the number of nonnative species and the proportion of total species richness represented by nonnative species. Native-anuran richness decreased along the watershed-disturbance gradient. We found both linear and nonlinear responses when relating species-richness attributes to the percentage of altered land (combined percentage of upland agriculture and developed land) in the associated watersheds, but the nonlinear responses cannot be considered land-use-related degradation-threshold responses. The breaks in the regression lines describing the relationship between the percentage of total species richness represented by nonnative plants and fish and altered land in our Pinelands watersheds did not represent a degradation threshold because, with the exception of the percentage of total species richness represented by nonnative-anuran species, a progressive decline in aquatic integrity was observed before the break points. Kruskal–Wallis ANOVA revealed significant differences in species-richness attributes only among stream impoundments with contrasting altered-land profiles, providing further evidence that aquatic degradation was progressive. Logistic regression identified the point along the watershed-disturbance gradient at which the probability of encountering nonnative bullfrogs was greater than that for native carpenter frogs. 相似文献
8.
The diversity and community structure of macrophyte vegetation was studied in 50 boreal lakes forming several upper reaches of lake chains around Lammi, southern Finland. Water chemical parameters and morphometry of the basins were included in a multivariate analysis. Floating-leaved vegetation was the dominant growth form, followed by emergent plants. In downstream lakes, the dominance of floating-leaved macrophytes declined, and emergent species increased in abundance. Species richness was highest in larger lakes, with a wider range of littoral habitats than smaller lakes. Electrical conductivity (range 18–151 mS cm−1, 25 °C) of the water correlated well with patterns in diversity among lakes, but this was not the case for nutrient concentrations. As a whole, morphometrical characteristics of lake basins showed better correlations with vegetation structure than any of the measured chemical parameters. The macrophyte vegetation of neighbouring lake chains differed considerably, depending on the surrounding landscape properties, water quality of the lakes and immigration history of plant species. 相似文献
9.
Genetic diversity and species diversity are expected to covary according to area and isolation, but may not always covary
with environmental heterogeneity. In this study, we examined how patterns of genetic and species diversity in stream fishes
correspond to local and regional environmental conditions. To do so, we compared population size, genetic diversity and divergence
in central stonerollers (Campostoma anomalum) to measures of species diversity and turnover in stream fish assemblages among similarly sized watersheds across an agriculture–forest
land-use gradient in the Little Miami River basin (Ohio, USA). Significant correlations were found in many, but not all, pair-wise
comparisons. Allelic richness and species richness were strongly correlated, for example, but diversity measures based on
allele frequencies and assemblage structure were not. In-stream conditions related to agricultural land use were identified
as significant predictors of genetic diversity and species diversity. Comparisons to population size indicate, however, that
genetic diversity and species diversity are not necessarily independent and that variation also corresponds to watershed location
and glaciation history in the drainage basin. Our findings demonstrate that genetic diversity and species diversity can covary
in stream fish assemblages, and illustrate the potential importance of scaling observations to capture responses to hierarchical
environmental variation. More comparisons according to life history variation could further improve understanding of conditions
that give rise to parallel variation in genetic diversity and species diversity, which in turn could improve diagnosis of
anthropogenic influences on aquatic ecosystems. 相似文献
10.
Thomas R. Hrabik Ben K. Greenfield David B. Lewis Amina I. Pollard Karen A. Wilson Timothy K. Kratz 《Ecosystems》2005,8(3):301-317
We evaluated several factors influencing the taxonomic richness of macrophytes, benthic invertebrates, snails, and fish in a series of northern Wisconsin lakes. We chose the study lakes to decouple the potential effects of ionic strength of lake water and stream connection, two factors that are usually highly correlated and therefore have been confounded in previous studies. In addition, our study lakes covered a wide range in a variety of characteristics, including residential development, abundance of exotic species, nutrient concentrations, predator abundance, and lake size. Species richness within each of the four taxonomic groups was significantly positively related to ionic strength (as measured by specific conductance); we also found secondary associations with other variables, depending on the specific group of organisms. The relationship between richness and lake area was dependent on the specific conductance of the lake and the vagility of the organisms; less vagile groups of organisms showed stronger and steeper species–area relationships in low-conductivity lakes. Further, after variance owing to specific conductance was removed, the presence of stream connections was positively related to species richness for fish, snails, and macrophytes as well as familial richness in benthic invertebrates. Our results indicate that lakes with relatively more groundwater input have lower extinction rates for all four groups of taxa and that lakes with stream inlets and outlets have enhanced immigration rates for fish, snails, benthic invertebrate families, and macrophytes. These findings link processes of immigration and extinction of four groups of organisms of varying vagility to landscape-level hydrologic characteristics related to the glacial history of the region. 相似文献
11.
From each of 46 watersheds in glaciated northwestern Pennsylvania we estimated phosphorus export (kg P/ha/yr) from weekly
or twice-weekly measured stream phosphorus concentrations and measured stream discharges, and determined land covers using
GIS. Simple and step-down multiple regression analyses yielded models that explained 24% of the variation in P export using
land cover within whole watersheds, and 64% of the variation using land cover within 200 m riparian buffers. We used these
models to predict P loading to seven lakes and found that predicted lake [P] was consistent with measured lake [P]. To estimate
pre-settlement lake [P] we reapplied the P export models with the assumption that human-impacted land covers were originally
forests. Predicted (hindcast) pre-settlement lake [P] indicated that six of the seven lakes were edaphically mesotrophic (10
< [P] < 20 μg/l). Lake remediation targets set on the assumption that area lakes were historically oligotrophic ([P] < 10 μg/l)
will be unattainable. 相似文献
12.
The evolutionary species pool hypothesis and patterns of freshwater diatom diversity along a pH gradient 总被引:2,自引:0,他引:2
Aim To interpret the unimodal relationship between diatom species richness and lake pH within the context of the evolutionary species pool hypothesis (SPH). We test the following primary prediction arising from the SPH: the size of the potential species pool (PSP) will increase along a gradient representing the historical commonness of different pH environments (pH commonness). To do this we assume that the present‐day spatial dominance of near‐neutral pH conditions compared with acidic and alkaline conditions reliably mimics the relative spatial availabilities of historical pH conditions among freshwater lakes. We also determine whether local richness represents a constant proportion of PSP size along the pH commonness gradient. Location Two hundred and thirty‐four lakes distributed over a 405,000 km2 region of the north‐eastern United States of America. Methods Sediment diatom morphospecies lists and pH data were acquired from the US Environmental Protection Agency's Environmental Monitoring and Assessment Program (EMAP) website. Using 248 morphospecies that occurred in at least 10 of the 234 lakes, four different measures of PSPs were calculated along the pH gradient. Local species richness was equated with the number of species occurring within the lake. Alpha diversity was equated with the average species richness of lakes with similar pH values. A combination of statistical methods were employed, including correlations, quadratic regression and piecewise regression. Results PSP size increased significantly with pH commonness for all four measures of PSP size, thus supporting the primary prediction of the evolutionary SPH. Local richness comprised a larger proportion of the PSP within acidic lakes than within circumneutral lakes. Alpha diversity and lake species richness both increased significantly with pH commonness, but the former did so in a two‐step fashion. We test and reject several alternative contemporary time‐scale explanations for our findings. Main Conclusions Our findings are consistent with the hypothesis that diatom taxonomic richness is presently lower within acidic and highly alkaline lakes than in circumneutral lakes owing to the limited opportunity in space and/or time for the evolution of suitably adapted species. Whereas ecological processes can explain why certain species are excluded from particular habitats, e.g. acidic lakes, they cannot account for why so few species are adapted to those habitats in the first place. 相似文献
13.
14.
Karen M. Stainbrook Karin E. Limburg Robert A. Daniels Robert E. Schmidt 《Hydrobiologia》2006,571(1):313-327
We examined long-term ecological change in two Hudson River tributaries, the Wappinger and Fishkill Creek watersheds in Dutchess
County, New York State. Fish data spanning 65 years (1936, 1988, 1992, and 2001) and shorter term macroinvertebrate data (1988,
2001) were used to assess the influence of land use practices. Between 1988 and 2001, macroinvertebrate index Biotic Assessment
Profile (BAP) improved by 113–165% in the Fishkill Creek watershed, and fish Index of Biotic Integrity (IBI) improved by 117–140%.
Fish IBI and fish species richness were significantly different (p < 0.01) between the watersheds, with Wappinger Creek in better condition. Long-term fish IBI scores showed degradation in both watersheds
since the 1930s. Changes in species composition suggest community homogenization on par with overall changes in the fish fauna
of New York. Most notable were increases in tolerant species and declines in intolerant or moderately tolerant species. Whereas
Fishkill Creek IBIs showed decline in 1988 relative to 1936, followed by improvement, Wappinger Creek declined monotonically
in environmental quality. Development has intensified in both watersheds, but Fishkill Creek is improving while Wappinger
Creek watershed is undergoing less mitigated degradation. We find that older, semi-quantitative data can be used to construct
environmental quality indicators, and can be of great use for measuring long-term change. 相似文献
15.
Impacts of urbanization on stream habitats and macroinvertebrate communities in the tributaries of Qiangtang River,China 总被引:2,自引:0,他引:2
The impacts of watershed urbanization on streams have been studied worldwide, but are rare in China. We examined relationships
among watershed land uses and stream physicochemical and biological attributes, impacts of urbanization on overall stream
conditions, and the response pattern of macroinvertebrate assemblage metrics to the percent of impervious area (PIA) of watersheds
in the middle section of the Qiantang River, Zhejiang Province, China. Environmental variables and benthic macroinvertebrates
of 60 stream sites with varied levels of watershed urban land use were sampled in April, 2010. Spearman correlation analysis
showed watershed urbanization levels significantly correlated with increased stream depth, width, and values of conductivity,
total nitrogen, ammonia, phosphate, calcium, magnesium, and chemical oxygen demand for the study streams. There was significant
difference in total taxa richness, Empheroptera, Plecoptera, and Trichoptera (EPT) taxa richness, and Diptera taxa richness,
percentages of individual abundances of EPT, Chironomidae, shredders, filterers, and scrapers, and Shannon–Wiener diversity
index between reference streams and urban impacted streams. In contrast, percentages of individual abundances for collectors,
oligochaeta, and tolerant taxa, and biotic index were significantly higher in urban impacted than reference streams. All the
above metrics were significantly correlated with PIA. The response patterns of total taxa richness, EPT taxa richness, and
Shannon–Wiener diversity index followed a drastic decrease at thresholds of 3.6, 3.7, and 5.5% of PIA, respectively. Our findings
indicate that stream benthic macroinvertebrate metrics are effective indicators of impacts of watershed urban development,
and the PIA-imperviousness thresholds we identified could potentially be used for setting benchmarks for watershed development
planning and for prioritizing high valued stream systems for protection and rehabilitation. 相似文献
16.
Species richness and distribution of eastern Australian lake chironomids and chaoborids 总被引:1,自引:0,他引:1
1. Chironomids and chaoborids were collected across eastern Australia and Tasmania in dune, glacial, sinkhole and maar lakes. Based on sampling exuviae from these relatively undisturbed freshwater lakes, we observed that species richness on the Australian continent was substantially greater than previously reported, and challenge the long‐standing view that chironomid species richness is depauperate in Australian lakes, compared with the northern hemisphere. 2. While chironomid species richness was equivalent across the four geographical regions sampled (tropical northern Queensland, Fraser Island, south‐eastern mainland Australia and Tasmania), there were only five ‘cosmopolitan’ species found across all regions. In general, species distributions were more closely associated with geographical region than with lake characteristics, and there were species assemblage differences among biogeographical regions. More than half of the 134 identified species were restricted to a single geographical region. Overall, Tasmanian lakes had the highest proportion of locally endemic species. 3. Latitude and altitude more strongly influenced species assemblages than did lake chemistry, although species richness sometimes varied among lake geomorphic types within a region. 相似文献
17.
The effects of different land use types on nutrient and chemical run-off have been widely researched, but the total effect
of change in land use on the aquatic species community is not well-known. For this study we researched the effect of land
use change on the vascular plant communities in lakes. The study was conducted with aerial photographs and GIS-techniques
in the countryside of central Finland. We compared the change in vascular plant species community structure with the change
in land use around 25 lakes, between the years 1933–1934 and 1996. The change in land use was analyzed in two different riparian
zones. We found several indications of links between changes in land use and aquatic vascular plant species. According to
our data a decrease in agricultural land use, in particular fields and meadows, appears to influence species turnover and
increases the number of new vascular plant species. When the changes in fields and meadows were added together and compared
to the change in species turnover, the correlation was even more evident. Changes in land use types in a zone 0–100 m from
the lake shoreline correlated with a change in vascular plant species more often than changes in a larger, adjacent zone,
100–400 m from the shore. This indicates that changes in the few hundred meters nearest the lake have the most elemental consequences
for aquatic vascular plant species, giving an indication of the breadth of the protection zones needed between freshwaters
and agricultural lands. 相似文献
18.
《Ecological Indicators》2008,8(5):431-441
This study used soil type, drainage class, parent material, and vegetation type to quantify the concentrations of lake water nitrogen for nine coastal lakes in forested watersheds in British Columbia, Canada. The results showed that forest soil type, drainage class, parent material, and vegetation type can predict more than 80% of the variance of nitrogen concentrations in these coastal lakes. The lakes in the watersheds with Orthic Humic Gleysol soils, moraine soil parent material, poor drainage, and coastal western hemlock and Douglas-fir vegetation type had higher nitrogen concentrations than the lakes in the watersheds with the other soil and vegetation types and properties. The impact factor of forest soil and vegetation on lake nitrogen concentration was defined according to the ability of each watershed soil and vegetation to contribute lake nitrogen input. This paper also demonstrates how to construct a model of lake nitrogen concentrations in response to the change of forest vegetation types and soil properties. The developed models can be used as watershed management tools for establishing and maintaining high quality water through managing soil and vegetation in forested watersheds. 相似文献
19.
1. Strong vertical gradients in light, water temperature, oxygen, algal concentration and predator encounters during summer in stratified lakes may influence patterns of depth selection in crustacean zooplankton, especially Daphnia species. 2. To test how crustacean depth selection varies among lakes along a gradient of catchment disturbance by recent residential development and land use change, we calculated the weighted mean depth distribution of the biomass of crustaceans by day and night in eight nutrient‐poor boreal lakes. 3. Generally, the greatest biomass of crustaceans was located at the metalimnion or at the lower boundary of the euphotic zone during thermal stratification in July. The crustacean zooplankton avoided warm surface layers and tended to stay in colder deep waters by both day and night. They also remained at greater depths in lakes with a more extensive euphotic zone. 4. There was some evidence of upward nocturnal migrations of large Daphnia and copepods in some lakes, and one case of downward migration in a lake inhabited by chaoborid larvae. 5. Multivariate regression trees (MRT) were used to cluster crustaceans and Daphnia species in homogeneous groups based on lake natural and disturbance factors. For crustaceans, the depth of the euphotic zone, the sampling depth (epilimnion, metalimnion and hypolimnion), time (day or night) of sampling and the biomass of chlorophyll a were the main driving factors. For Daphnia species, the drainage area, the sampling depth, the cleared land surface area within the catchment and the concentration of total dissolved phosphorus were the main factors. 相似文献