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1.
Pooled water beetle species lists from 1826 British national grid 10-km squares were analysed using multivariate ordination and classification methods. The relationships of pool groups to the climate, altitude and land cover variables were assessed using constrained and partial ordinations. Ordination of the species pool data indicated a major trend between squares in the north-west of Scotland and those in southern England, illustrating differences in acid and basic water standing water. Secondary variation was from acid standing water to fast-flowing streams and rivers. Classification generated nine species pool groups. These showed a distinct north-west to south-east trend but there was no obvious coastal or brackish water effect on distribution. The climatic and land cover variables were all significantly related to each other, and to north-south variation in grid square location, but the constrained ordination results indicated that that the most important influence on water beetle species pool distribution was mean summer temperature. Although the amount of variation explained by the environmental variables was low, spatial variation in the environmental predictors was almost as important as the environmental variables themselves in determining species pool composition. Mean annual temperature was also strongly correlated with species pool distribution with two land cover variables slightly less important. Altitude and precipitation had the least influence. The water beetle national recording scheme database appears to be of sufficiently high quality for environmental investigations at the British scale. There is considerable potential for the synthesis of invertebrate species distribution, land cover and climate change predictions in the assessment of environmental change. The results, together with previous work on other invertebrate species, indicate that changing summer temperatures may have a considerable influence on the distribution British invertebrate species.  相似文献   

2.
The advent of remote-sensed satellite land cover data has provided the opportunity to assess the relationship between invertebrate species distributions and individual land cover types. Water beetle species occur in habitats within specific land cover types and the relationship between the distribution of water beetle species and land covers at the regional scale was investigated using records of 154 species from 1018 sites in north-east England. The land covers of tilled land and urban in the lowlands and of shrub heath and heath grassland in the upland areas proved to be most important in explaining the distribution of species. There were both positive and negative associations between some species and other covers such as woodland and the coast. However, a considerable number of species, generally those with a large number of records, showed no strong relationships with any land cover types. The integration of water beetle species recording data and remote-sensed land cover data as a basis for predicting and monitoring both species distribution and environmental change is discussed.  相似文献   

3.
Aims To determine the relationship between satellite‐derived land cover data and distribution patterns of water beetle species pools. Location A total of 687 British national grid 10 km squares in Scotland and 588 1 km grid squares in 99 10 km grid squares in northeast England. Methods Multivariate classification and constrained ordination analyses were used with water beetle species and land cover data. Results The major variation in both the Scotland and northeast England 10 km species pools was from squares with upland acid water habitats to squares with lowland fens and ponds whilst for the 1 km northeast England data it was from squares dominated by fast‐flowing streams and rivers to those with fens and ponds. The secondary variations in the 10 and 1 km analyses were the primary ones juxtaposed. Constrained ordination of the Scottish 10 km data showed upland land cover types to be most influential in determining species pool distribution whilst lowland covers were more important with both the 10 and 1 km northeast England pools. The three analyses showed that coastal cover had a relatively high influence on species pool distribution but no species pool group was dominated by coastal species. Main conclusions There were strong relationships between water beetle species pool distributions and the satellite‐derived land cover types dominating upland and lowland areas. The major variation in the northeast England species pool data differed at the two scales analysed. Results indicated that there is considerable potential for the synthesis of water beetle distribution and land cover data for use in environmental and conservation monitoring at both the regional and national scales.  相似文献   

4.
Aims and methods Ground beetle and satellite‐derived land cover data from 1687 United Kingdom 10 km national grid squares were used to assess the relationship between species pool and cover data in Great Britain using fuzzy classification and constrained ordination. Results Ground beetle species pools classified into nine groups which were related to land cover variables using constrained ordination. There was a strong relationship between upland land cover and three ground beetle groups. Deciduous woodland, coastal and tilled land were associated with three other groups. Three further groups did not appear to be strongly associated with any particular cover, but differed in geographical position. Conclusion The distribution of species pools derived from the British national recording scheme at the 10 km scale was strongly related to satellite‐derived land cover data. There appears to be considerable potential for the use of a synthesis of land cover and ground beetle data in the monitoring of environmental change over a large, countrywide, area.  相似文献   

5.
A total of 78 brownfield (post-industrial and urban) sites were surveyed for beetles between 1991 and 2001 throughout England using pitfall traps. The distribution of ground, rove and phytophagous beetle assemblages was investigated using ordination and classification analyses. Site drainage and vegetation cover had a profound effect on the distribution of ground and rove beetle assemblages but site location was also important for phytophagous beetle assemblages. A total of 182 records of 46 nationally rare and scarce species (16 ground, 10 rove and 20 phytophagous species) were generated. A number of these species are more usually associated with other, more natural habitats such as riverine sediments, sandy heaths and chalk grassland. Brownfield sites provide habitat conditions similar to more natural habitats and they may help maintain populations of some rare and scarce species. The results indicate that brownfield sites are important habitats for beetles and there is evidence that the situation is similar for other invertebrate groups. There should be no further assumptions that post-industrial and urban sites have no conservation interest.  相似文献   

6.
Exposed riverine sediments (ERS) by four rivers in Scotland and northern England were sampled for beetles in 1996 and 1997. One hundred and sixty rove beetle (Staphylinidae) species lists were analysed using ordination and classification techniques in order to identify habitat groups within and between catchments and to assess which factors were affecting species assemblage distribution. There were major differences between the species assemblages of ERS by rivers of highland and lowland catchments. Within catchments, assemblage distribution was mainly influenced by the position of sites within the catchment; vegetation cover and sediment composition had less influence. The number of rove beetle habitats was not the same as those for ground and phytophagous beetle groups, indicating that conservation considerations should take into account variations in ERS habitat diversity. A considerable number of records of nationally rare and scarce rove beetle species were recorded, most on ERS by rivers and tributaries unaffected by river management or engineering.  相似文献   

7.
Carabid beetles and environmental parameters were investigated in 52 grassland sites with three replicate pitfall traps in each site and in the valley of the River Eider in Schleswig–Holstein (northern Germany) with 61 pitfall traps. Environmental parameters included water content of soil, sand content, organic matter content and pH. Ground beetle assemblages were derived by detrended correspondence analyses (DCA) and characterised by the specific environmental conditions as means for each assemblage. On the regional scale including all investigated sites of Schleswig–Holstein, five assemblages were differentiated. On the local scale including the investigated sites in the valley of the River Eider, three assemblages were found corresponding well with those found on the regional scale. Environmental conditions at the sites of the five assemblages were correlated with land use data, soil types, and water level stages provided by three maps of a geographic information system (GIS). The GIS maps were combined to develop smaller areas with land use, soil type and water level stage information. The characteristic environmental conditions were assigned to each area to derive the spatial distribution of the five ground beetle assemblages. Spatial prediction was correct for 65% of investigated sites. The potential area of each assemblage was estimated for the valley. The different grassland areas were evaluated as potential habitats for ground beetle species comparing total species richness with the regional species richness of each assemblage. The comparison shows that species richness in the evaluated assemblages is relatively low compared to the regional potential.  相似文献   

8.
Investigations concerned with ground beetle (Carabidae) dynamics in the agroecosystem have generally been limited to relatively short time periods in one crop, commonly wheat, whilst other studies have concentrated on the influence of landscape structure and non-crop habitat on beetle activity, again usually in one crop. Results of a seven-year survey at Nafferton in northern England, with recording from all crops in an organic rotation and from three types of field boundary, indicated that the lack of field boundary management had the greatest influence on ground beetle activity/density in this particular agroecosystem. However, within the crop rotation, grass/clover limited activity/density compared with that in cereal, potato and bean crops and there were also differences within cereal crops. Data from a 17-year survey at Drayton Environmental Change Network (ECN) site in midland England indicate that previous understanding of ground beetle activity and distribution in intensively managed landscapes may have been limited by temporal constraints. At Drayton, changes in surrounding crop cover, with the introduction of willow coppice and reduced area of arable land and agricultural inputs, considerably influenced ground beetle activity/density and assemblages in non-crop habitat. Small, active species dominating the assemblage in the first few years of the Drayton survey were gradually replaced by larger, non-flying species, especially after all the willow coppice had been planted. In both surveys, activity/density of ground beetles was related to disturbance, affecting vegetation cover and structure, but at the field scale at Nafferton and at the farm scale at Drayton. Longer surveys in a variety of landscapes such as those by the United Kingdom Environmental Change Network are likely to improve understanding of activity, diversity and distribution of invertebrates, which are fundamental requirements if predators such as ground beetles are required for ecosystem service provision.  相似文献   

9.
M. D. Eyre  M. L. Luff 《Ecography》2004,27(4):417-426
Distribution data concerning 172 ground beetle species derived from 1145 pitfall trap sites in northern England and southern Scotland were used to assess the relationship between species distribution and 12 satellite-derived land cover variables at the regional scale. A number of species were strongly associated with one cover type and negatively with others. The major variation was for preferences for covers in upland or lowland parts of the region. Other distinct preferences for some species were covers such as those at the coast whilst a number of common species showed no strong preference for any cover variable. The synthesis of ground beetle species distribution and satellite-derived cover data is discussed in relation to environmental assessment and change.  相似文献   

10.
Multivariate techniques were used to compare and contrast the effects of land cover and farming practice on ground beetle and spider assemblages of Scottish farmland. For both ground beetles and spiders, the ordination and fuzzy clustering of sites were related to land cover rather than geographical location or year of sampling. The same four types of land cover group were identified: that is, heather moorland, semi-natural grassland, intensive grassland and arable land. The robustness of these land cover groups was tested using previously unsampled sites and it was found that 79 and 86% of sites, for ground beetle and spider assemblages respectively, were allocated to the land cover group predicted from their actual land cover. Furthermore, procrustes rotational analysis found a strong relationship between ground beetle and spider assemblages in intensively managed sites, suggesting that the assemblage structure of one group could be used to predict that of the other. The observed relationship between spider and ground beetle assemblages does not necessarily indicate that both groups were responding to agricultural practices in the same way. Indeed, the highest number of beetle species occurred in intensively managed grassland and arable sites while the highest number of spider species occurred in semi-natural grassland and heather sites. When conducting ecological assessments, one might wish to collect information on a wide range of ecologically different taxa; however, financial constraints make this unfeasible. From the results it could be concluded that spiders should be chosen in preference to ground beetles when seeking to make predictions on how farming practices influence invertebrates. However, such a conclusion would be premature since not only were spiders more numerous in the traps, but they were also more time consuming to process. In addition, the strong relationship found between the spider and ground beetle assemblages further justifies carabids as a target group when monitoring the influence of farming practices on biodiversity.  相似文献   

11.
The macroinvertebrate species and assemblages of headwater streams of the River Tyne catchment in northern England were classified and their relationship with environmental variables based on stream structure, water acidity, distance from source and land cover investigated using constrained ordination and logistic regression. Fuzzy classification of data from 322 stream sites generated five assemblages. Stream structure, quantified as an exposure index, was found to be the most important environmental variable, with water acidity also important. Distance from source and land cover had less influence on species and assemblage distribution. A considerable amount of variation in assemblage distribution was explained using a two-variable logistic regression with stream structure (exposure index) and water acidity (pH) in a template. Site structure and water acidity appeared to be related to drift, geology and topography with little anthropogenic influence. The applicability of the habitat template concept for explaining the distribution of stream macroinvertebrates is discussed.  相似文献   

12.
Beetle assemblages in ponds: effects of habitat and site age   总被引:11,自引:1,他引:10  
  • 1 Water beetle assemblages were sampled in each of 18 freshwater ponds, including 11 recently constructed sites designed to provide mitigation for wetlands destruction elsewhere, and seven older reference sites. There were three objectives: (a) to relate taxon richness and biomass of the beetles to the same properties of the wider aquatic invertebrate community, (b) to evaluate changes in beetle assemblage structure over time, and (c) to determine habitat effects on taxonomic composition, mean body size and trophic guild structure of the beetle assemblage.
  • 2 Forty‐seven beetle genera were identified, representing 77 species. The beetles represented an average of 21.5% of total generic richness, but only 3.7% of total wet biomass of the wider invertebrate community.
  • 3 Of all variables evaluated using canonical correspondence analysis (CCA), site age had the greatest influence on the beetle assemblage. Predatory dytiscids were early colonists at younger sites, while herbivorous curculionids and chrysomelids associated with particular types of vegetation typically occurred in older ponds. Mitigation ponds and reference ponds supported similar numbers of species. Reference sites, however, harboured substantially more unique species found at only a single site within the study area.
  • 4 The presence of fish was also strongly related to beetle assemblage structure. Ponds with few or no fish contained about 3‐fold higher biomass and 3‐fold greater mean wet weight per individual compared to ponds with substantial fish assemblages.
  • 5 Beetle assemblage composition varied among sites and sampling years, but beetle biomass, richness and species composition may be useful tools in evaluating the success of wetland mitigation efforts.
  相似文献   

13.
The diversity of beetle assemblages in different habitat types (primary forest, logged forest, acacia plantation and oil palm plantation) in Sabah, Malaysia was investigated using three different methods based on habitat levels (Winkler sampling, flight-interception-trapping and mist-blowing). The overall diversity was extremely high, with 1711 species recorded from only 8028 individuals and 81 families (115 family and subfamily groups). Different degrees of environmental changes had varying effects on the beetle species richness and abundance, with oil palm plantation assemblage being most severely affected, followed by acacia plantation and then logged forest. A few species became numerically dominant in the oil palm plantation. In terms of beetle species composition, the acacia fauna showed much similarity with the logged forest fauna, and the oil palm fauna was very different from the rest. The effects of environmental variables (number of plant species, sapling and tree densities, amount of leaf litter, ground cover, canopy cover, soil pH and compaction) on the beetle assemblage were also investigated. Leaf litter correlated with species richness, abundance and composition of subterranean beetles. Plant species richness, tree and sapling densities correlated with species richness, abundance and composition of understorey beetles while ground cover correlated only with the species richness and abundance of these beetles. Canopy cover correlated only with arboreal beetles. In trophic structure, predators represented more than 40% of the species and individuals. Environmental changes affected the trophic structure with proportionally more herbivores (abundance) but fewer predators (species richness and abundance) in the oil palm plantation. Biodiversity, conservation and practical aspects of pest management were also highlighted in this study.  相似文献   

14.
A sufficiently large body of knowledge on British ground beetle (Carabidae) communities now exists to allow investigation of whether habitats may be classified or described on the basis of their ground beetle communities, in the same way that the National Vegetation Classification (NVC) describes British plant communities. A data set of ground beetle abundances from pitfall traps at 481 sites in a range of natural, semi-natural and agricultural habitats throughout Scotland was available for analysis. Multivariate analysis (detrended correspondence analysis and fuzzy cluster analysis) was carried out on proportional catch data of 156 species of ground beetle from 444 of these sites and the results related to the NVC of the sites.
Initial analysis classified the sites into five broad categories: 1) peatlands, 2) calcifugous, 3) mesotrophic, 4) dry river sediments and 5) damp river sediments. Further analysis identified 15 ground beetle assemblages, each corresponding to a relatively well defined vegetation type within one of these broad categories. The major environmental factors appearing to determine the distribution of ground beetle assemblages were substratum type, disturbance and soil moisture, all of which are also important determinants of the distribution of plant communities. The presence and absence of relatively stenotopic species were important discriminants of certain habitats such as wetlands and river sediments but the relative abundances within assemblages of more eurytopic species provided good indications of a relationship between ground beetle assemblages and NVC categories.  相似文献   

15.
Anthropogenic disturbance in natural ecosystems reduces the number of species in biological communities and homogenizes their composition across different regions. Climate is one of the main abiotic determinants of species distributions and different factors were proposed as the main climatic drivers. Here we explored the role of regional climate on the local response of dung beetle assemblages to the replacement of native forest by cattle pastures in South America by simultaneously contrasting three climatic hypotheses: energy, seasonality and heterogeneity. We compiled a database by searching published studies comparing dung beetle richness and composition between both native forests and cattle pastures. We calculated the proportional difference in species richness and composition between habitat types. As explanatory variables, we used seven abiotic variables grouped into the three climatic hypotheses. Energy/Productivity: mean annual temperature (°C/year) and total annual precipitation (mm/year). Seasonality: annual thermal amplitude (°C/year), the average coefficient of variation of monthly precipitation and the coefficient of average monthly variation in temperature. Heterogeneity: coefficient of variation of mean annual temperature, coefficient of variation of mean annual precipitation. Using regression analyses and a model selection procedure, we found differences in species richness between native forests and cattle pastures were explained by the coefficient of variation of mean annual precipitation, whereas changes in species composition were explained by total annual precipitation and the coefficient of variation of mean annual precipitation. The response of dung beetle assemblages to livestock grazing in South American forests was associated with precipitation variation. The heterogeneity hypothesis better explained changes in species richness following forest replacement by cattle pastures, while both energy/productivity and heterogeneity hypotheses explained the changes in species composition.  相似文献   

16.
17.
Plant, spider, beetle, and ground beetle communities were studied in different agrolandscape biotopes (a wheat field, a field margin, and a forest belt) of Krasnodar Territory. In these biotopes, borders between plant communities were distinct. On the contrary, arthropod communities were not usually confined to the certain biotopes. The high degree of mobility of arthropod species resulted in a decrease in their association with the biotope. Representatives of some species (especially, beetles) were revealed in all the biotopes. In relation to season and some other factors, they frequently concentrated in different biotopes. Analysis of arthropod assemblages only within a single biotope gives us a rather impoverished knowledge of the whole population. It is necessary to study these assemblages not only within the basic biotope, but also in adjacent ones.  相似文献   

18.
A survey of invertebrates on exposed riverine sediments (ERS) in four catchments of rivers in Scotland and northern England was carried out in 1996 and 1997 using pitfall traps. The resulting 179 lists of ground beetle species were used in ordination and classification analyses to determine the different types of habitats and the environmental factors influencing species assemblage distribution. Types of ERS habitat differed between highland and lowland catchments; there were also different numbers of habitat types in each catchment. The distribution of ERS within catchments was related to geology, position in catchment, sediment composition and the amount of vegetation. Evidence of the positive nature of river engineering was identified and the role of river management is discussed. The numbers of nationally rare and scarce ground beetle species recorded from the ERS habitats in each catchment are reported and the factors affecting their distribution discussed.  相似文献   

19.
202 running-water sites in the catchment of the River Rede, a tributary of the River Tyne in northern England, were sampled for invertebrates in 1990. The distributions of water beetle species were investigated using logistic regression with several environmental factors. A number of site structure characteristics were assessed and the presence or absence of silt (as peat or clay) was found to be the most important single variable. Shingle, pebbles, cobbles, boulders and the amount of vegetation present were less important substrate variables. The distance from stream source reflected substrate structure and site gradient was a poor determinant of species distribution. A composite variable, termed the exposure index, was derived from all the site structure characteristics using an ordination and was found to be useful in explaining species distribution. Water pH also affected distributions considerably. Two variable analyses using the exposure index and water pH gave the best explanation of species distribution. The two variables used together were a reflection of productivity and disturbance, the two main components of habitat templates and strategy theory. The distribution of water beetle species in the Rede catchment was a product of these factors, which, in turn, were a product of the geography of the catchment.  相似文献   

20.
盐池四墩子拟步甲昆虫群落组成与环境因子的相关性   总被引:2,自引:0,他引:2  
2009年3-10月,对宁夏盐池四墩子不同植被类型和人工干扰强度的荒漠草地的拟步甲昆虫群落结构及其环境因子特征进行了调查, 采用多样性指数和典范对应分析(CCA)研究了昆虫群落与环境因子之间的相关性.共收集拟步甲10属20种,5431只,以弯齿琵甲、克小鳖甲和蒙古漠王占优势,分别占总数的47.30%、39.90%和3.59%.CCA分析表明:拟步甲与环境因子之间的相关性高达100%,提示盐池四墩子环境因子变化影响拟步甲的分布,植物群落多样性、植物生物量和土壤含水量对拟步甲昆虫群落的分布影响最大;从物种的分布状况看,谢氏宽漠王对环境最为敏感;小丽东鳖甲、宽突东鳖甲、尖尾东鳖甲、宽腹东鳖甲次之,与植物生物量、植被盖度呈负相关,戈壁琵甲、中华砚甲、网目土甲和淡红毛隐甲与植被密度和土壤含水量呈正相关,蒙古漠王、克小鳖甲、小皮鳖甲和异距琵甲与植物群落多样性呈正相关,奥氏真土甲、弯齿琵甲和达氏琵甲与植物生物量和植被盖度呈正相关;相关和回归分析结果也显示,拟步甲群落的活动密度与土壤含水量极显著正相关(r=0.943,P=0.005).同时,排序反映了拟步甲对生态环境的需求以及其在不同资源维上的生态分化现象.  相似文献   

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