Abstract. Human population growth is expected to drive several species to local extinction. Yet, an unexpected high biodiversity can be found even in densely populated areas. Although a positive correlation between human density and biodiversity can be explained by the intermediate disturbance hypothesis, an alternative possible explanation may come from the tendency of human settlements to be located in sites whose environmental conditions are particularly favourable also for many other animal species. To investigate this hypothesis, we studied the relationships between human population density and species richness of native tenebrionid beetles in small Italian islands. We used partial regression analysis to assess the individual contribution of island area (to account for the species–area relationship), elevation (used as a proxy of environmental diversity), and human density to species richness. We found that tenebrionid diversity increased with human population density even after controlling for area and elevation. This may suggest that islands that were (and are) more hospitable to humans are also those which can be more favourable for tenebrionids.
{"title":"Human population density and tenebrionid richness covary in Mediterranean islands","authors":"S. Fattorini, G. Strona","doi":"10.5194/WE-16-63-2016","DOIUrl":"https://doi.org/10.5194/WE-16-63-2016","url":null,"abstract":"Abstract. Human population growth is expected to drive several species to local extinction. Yet, an unexpected high biodiversity can be found even in densely populated areas. Although a positive correlation between human density and biodiversity can be explained by the intermediate disturbance hypothesis, an alternative possible explanation may come from the tendency of human settlements to be located in sites whose environmental conditions are particularly favourable also for many other animal species. To investigate this hypothesis, we studied the relationships between human population density and species richness of native tenebrionid beetles in small Italian islands. We used partial regression analysis to assess the individual contribution of island area (to account for the species–area relationship), elevation (used as a proxy of environmental diversity), and human density to species richness. We found that tenebrionid diversity increased with human population density even after controlling for area and elevation. This may suggest that islands that were (and are) more hospitable to humans are also those which can be more favourable for tenebrionids.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"8 1","pages":"63-65"},"PeriodicalIF":2.2,"publicationDate":"2016-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87315584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Evaluating socio-economic losses due to natural disasters is a challenging task because of the combined complexity of the social and ecological systems affected. However, also under pressure from the expected effects of climate change, evaluating the socio-economic costs of natural catastrophes has become a vital need for policy makers, urban planners, and private agents (such as insurance companies and banks). This paper suggests a general framework encompassing all the important concepts which should be taken into account by the above agents in the assessment of natural disasters. In particular, we propose a simple and consistent set of relationships among vulnerability, resilience, hazard, risk, damage, and loss which can guide socio-economic assessment.
{"title":"Vulnerability, resilience, hazard, risk, damage, and loss: a socio-ecological framework for natural disaster analysis","authors":"M. Modica, Roberto Zoboli","doi":"10.5194/WE-16-59-2016","DOIUrl":"https://doi.org/10.5194/WE-16-59-2016","url":null,"abstract":"Abstract. Evaluating socio-economic losses due to natural disasters is a challenging task because of the combined complexity of the social and ecological systems affected. However, also under pressure from the expected effects of climate change, evaluating the socio-economic costs of natural catastrophes has become a vital need for policy makers, urban planners, and private agents (such as insurance companies and banks). This paper suggests a general framework encompassing all the important concepts which should be taken into account by the above agents in the assessment of natural disasters. In particular, we propose a simple and consistent set of relationships among vulnerability, resilience, hazard, risk, damage, and loss which can guide socio-economic assessment.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"18 1","pages":"59-62"},"PeriodicalIF":2.2,"publicationDate":"2016-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79136815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Kagezi, M. Kaib, P. Nyeko, C. Bakuneeta, M. Schädler, J. Stadler, R. Brandl
Abstract. Tropical forests are faced with a substantial loss of forest cover due to human activities. The various forms of land use influence habitat structure, microclimate, and co-occurring species, with possible effects on ecosystem processes. The forests of western Kenya are the most eastern parts of the Congolian rainforests. Due to the high human population density only few remnants of these rainforests remained. Even protected areas are influenced by human disturbances, with unknown effects on ecosystem processes. Therefore, we quantified the mass loss of leaf litter with and without access of soil invertebrates within forest fragments and sites affected by increasing levels of agricultural land-use intensity in the Kakamega area (western Kenya; 1500 m a.s.l.). Mass loss of litter as an estimate of decomposition rate increased with rainfall during the annual cycle. Furthermore, mass loss increased with the area of forest fragments and decreased with land-use intensification. We found that soil invertebrates had only small effects on mass loss (
{"title":"Impacts of land-use intensification on litter decomposition in western Kenya","authors":"G. Kagezi, M. Kaib, P. Nyeko, C. Bakuneeta, M. Schädler, J. Stadler, R. Brandl","doi":"10.5194/WE-16-51-2016","DOIUrl":"https://doi.org/10.5194/WE-16-51-2016","url":null,"abstract":"Abstract. Tropical forests are faced with a substantial loss of forest cover due to human activities. The various forms of land use influence habitat structure, microclimate, and co-occurring species, with possible effects on ecosystem processes. The forests of western Kenya are the most eastern parts of the Congolian rainforests. Due to the high human population density only few remnants of these rainforests remained. Even protected areas are influenced by human disturbances, with unknown effects on ecosystem processes. Therefore, we quantified the mass loss of leaf litter with and without access of soil invertebrates within forest fragments and sites affected by increasing levels of agricultural land-use intensity in the Kakamega area (western Kenya; 1500 m a.s.l.). Mass loss of litter as an estimate of decomposition rate increased with rainfall during the annual cycle. Furthermore, mass loss increased with the area of forest fragments and decreased with land-use intensification. We found that soil invertebrates had only small effects on mass loss (","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"11 1","pages":"51-58"},"PeriodicalIF":2.2,"publicationDate":"2016-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87867314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Habitat fragmentation caused by urbanization is considered a prominent threat to biodiversity. Urban development creates a mosaic of natural fragments which can be occupied by organisms able to survive in small spaces. These fragments are a set of habitat islands separated by less suitable non-native habitats. Because of their isolation, communities of urban green spaces can be investigated using hypotheses developed in island biogeography. The "equilibrium theory of island biogeography" (ETIB) allows the formulation of some predictions about how various characteristics of green spaces (such as their area, shape, level of isolation, environmental heterogeneity, age) should influence species richness. Many studies found support for ETIB predictions, but results varied considerably according to the species' sensitivity to patch size, matrix characteristics, and history of the city. In some cases ETIB predictions were falsified. These contrasting results warn against making generalizations on conservation strategies only based on ETIB models. On the other hand, the ETIB may represent a useful framework for urban conservation, especially for small animals like insects, if the roles of other factors, such as the surrounding landscape, the specific needs of the species under study, and the history of the urbanization process, are taken into account.
{"title":"Insects and the city: what island biogeography tells us about insect conservation in urban areas","authors":"S. Fattorini","doi":"10.5194/WE-16-41-2016","DOIUrl":"https://doi.org/10.5194/WE-16-41-2016","url":null,"abstract":"Abstract. Habitat fragmentation caused by urbanization is considered a prominent threat to biodiversity. Urban development creates a mosaic of natural fragments which can be occupied by organisms able to survive in small spaces. These fragments are a set of habitat islands separated by less suitable non-native habitats. Because of their isolation, communities of urban green spaces can be investigated using hypotheses developed in island biogeography. The \"equilibrium theory of island biogeography\" (ETIB) allows the formulation of some predictions about how various characteristics of green spaces (such as their area, shape, level of isolation, environmental heterogeneity, age) should influence species richness. Many studies found support for ETIB predictions, but results varied considerably according to the species' sensitivity to patch size, matrix characteristics, and history of the city. In some cases ETIB predictions were falsified. These contrasting results warn against making generalizations on conservation strategies only based on ETIB models. On the other hand, the ETIB may represent a useful framework for urban conservation, especially for small animals like insects, if the roles of other factors, such as the surrounding landscape, the specific needs of the species under study, and the history of the urbanization process, are taken into account.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"31 1","pages":"41-45"},"PeriodicalIF":2.2,"publicationDate":"2016-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78360072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rosa M. Chefaoui, S. Chozas, O. Correia, Ana M. C. Santos, J. Hortal
Abstract. Dune plant assemblages are affected by severe conditions, which makes them excellent models for studying the effects of species interactions and environmental conditions on community structure. We evaluate the relationship between the structure of dune communities, local environmental conditions and the suitability of climatic conditions for their characteristic species. Using data from an extensive survey of xerophytic inland sand dune scrub communities from Portugal – one of the most threatened habitat types of Europe – we identify the main gradients of vegetation composition, the different types of communities and their indicator shrub species. Then, we model the geographical responses of these species to the environment. Soil organic matter, isothermality and the habitat suitability for Stauracanthus genistoides defined the distribution of three shrub communities in the study area.
{"title":"Using niche models of indicator species to predict the distribution of xerophytic shrub dune communities","authors":"Rosa M. Chefaoui, S. Chozas, O. Correia, Ana M. C. Santos, J. Hortal","doi":"10.5194/WE-16-47-2016","DOIUrl":"https://doi.org/10.5194/WE-16-47-2016","url":null,"abstract":"Abstract. Dune plant assemblages are affected by severe conditions, which makes them excellent models for studying the effects of species interactions and environmental conditions on community structure. We evaluate the relationship between the structure of dune communities, local environmental conditions and the suitability of climatic conditions for their characteristic species. Using data from an extensive survey of xerophytic inland sand dune scrub communities from Portugal – one of the most threatened habitat types of Europe – we identify the main gradients of vegetation composition, the different types of communities and their indicator shrub species. Then, we model the geographical responses of these species to the environment. Soil organic matter, isothermality and the habitat suitability for Stauracanthus genistoides defined the distribution of three shrub communities in the study area.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"29 1","pages":"47-49"},"PeriodicalIF":2.2,"publicationDate":"2016-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75610003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Tchebakova, N. A. Kuzmina, E. Parfenova, V. Senashova, S. R. Kuzmin
Abstract. Needle cast caused by fungi of the genus Lophodermium Chevall. is a common disease in pine trees in Siberia. Regression analyses relating needle cast events to climatic variables in 1997–2010 showed that the disease depended most on precipitation of two successive years. Temperature conditions were important to trigger the disease in wetter years. We used our regional bioclimatic envelope model and IPCC scenarios to model the needle cast distribution and its outbreaks in the 21st century. In a warming climate, the needle cast range would shift northwards. By 2020, needle cast outbreaks would already have damaged the largest forest areas. But outbreak areas would decrease by 2080 because the ranges of modeled pathogen and Scots pine, the disease host, would separate: the host tree progression would be halted by the slower permafrost retreat, which would in turn halt the potential pathogen progression.
{"title":"Potential climate-induced distributions of Lophodermium needle cast across central Siberia in the 21 century","authors":"N. Tchebakova, N. A. Kuzmina, E. Parfenova, V. Senashova, S. R. Kuzmin","doi":"10.5194/WE-16-37-2016","DOIUrl":"https://doi.org/10.5194/WE-16-37-2016","url":null,"abstract":"Abstract. Needle cast caused by fungi of the genus Lophodermium Chevall. is a common disease in pine trees in Siberia. Regression analyses relating needle cast events to climatic variables in 1997–2010 showed that the disease depended most on precipitation of two successive years. Temperature conditions were important to trigger the disease in wetter years. We used our regional bioclimatic envelope model and IPCC scenarios to model the needle cast distribution and its outbreaks in the 21st century. In a warming climate, the needle cast range would shift northwards. By 2020, needle cast outbreaks would already have damaged the largest forest areas. But outbreak areas would decrease by 2080 because the ranges of modeled pathogen and Scots pine, the disease host, would separate: the host tree progression would be halted by the slower permafrost retreat, which would in turn halt the potential pathogen progression.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"104 3 1","pages":"37-39"},"PeriodicalIF":2.2,"publicationDate":"2016-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83410906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. Scapin, M. Zucchetta, C. Facca, A. Sfriso, P. Franzoi
A fish-based multimetric index was applied to assess the ecological status of fish fauna in both natural and newly restored seagrass meadows in the Venice lagoon (northern Adriatic Sea, Italy), using natural habitats as reference sites. Fish assemblages were then compared, and community attributes of recreated and natural habitats were evaluated. Ecological status resulted higher in natural meadows, and a multivariate analysis showed that an increase in the relative proportion of seagrass specialists at restored sites could represent an indicator of success of seagrass restoration.
{"title":"Using fish assemblage to identify success criteria for seagrass habitat restoration","authors":"L. Scapin, M. Zucchetta, C. Facca, A. Sfriso, P. Franzoi","doi":"10.5194/WE-16-33-2016","DOIUrl":"https://doi.org/10.5194/WE-16-33-2016","url":null,"abstract":"A fish-based multimetric index was applied to assess the ecological status of fish fauna in both natural and newly restored seagrass meadows in the Venice lagoon (northern Adriatic Sea, Italy), using natural habitats as reference sites. Fish assemblages were then compared, and community attributes of recreated and natural habitats were evaluated. Ecological status resulted higher in natural meadows, and a multivariate analysis showed that an increase in the relative proportion of seagrass specialists at restored sites could represent an indicator of success of seagrass restoration.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"177 1","pages":"33-36"},"PeriodicalIF":2.2,"publicationDate":"2016-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76616205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. Countries in south-eastern Europe are cooperating to conserve a sub-endemic lynx species, Lynx lynx martinoi. Yet, the planning of species conservation should go hand-in-hand with the planning and management of (new) protected areas. Lynx lynx martinoi has a small, fragmented distribution with a small total population size and an endangered population. This study combines species distribution modelling with spatial prioritisation techniques to identify conservation areas for Lynx lynx martinoi. The aim was to determine locations of high probability of occurrence for the lynx, to potentially increase current protected areas by 20 % in Albania, the former Yugoslav Republic of Macedonia, Montenegro, and Kosovo. The species distribution modelling used generalised linear models with lynx occurrence and pseudo-absence data. Two models were developed and fitted using the lynx data: one based on natural factors, and the second based on factors associated with human disturbance. The Zonation conservation planning software was then used to undertake spatial prioritisations of the landscape using the first model composed of natural factors as a biological feature, and (inverted) a second model composed of anthropological factors such as a cost layer. The first model included environmental factors as elevation, terrain ruggedness index, woodland and shrub land, and food factor as chamois prey (occurrences) and had a prediction accuracy of 82 %. Second model included anthropological factors as agricultural land and had a prediction accuracy of 65 %. Prioritised areas for extending protected areas for lynx conservation were found primarily in the Albania–Macedonia–Kosovo and Montenegro–Albania–Kosovo cross-border areas. We show how natural and human factors can be incorporated into spatially prioritising conservation areas on a landscape level. Our results show the importance of expanding the existing protected areas in cross-border areas of core lynx habitat. The priority of these cross-border areas highlight the importance international cooperation can play in designing and implementing a coherent and long-term conservation plan including a species conservation plan to securing the future of the lynx.
{"title":"Incorporating natural and human factors in habitat modelling and spatial prioritisation for the Lynx lynx martinoi","authors":"K. Laze, A. Gordon","doi":"10.5194/WE-16-17-2016","DOIUrl":"https://doi.org/10.5194/WE-16-17-2016","url":null,"abstract":"Abstract. Countries in south-eastern Europe are cooperating to conserve a sub-endemic lynx species, Lynx lynx martinoi. Yet, the planning of species conservation should go hand-in-hand with the planning and management of (new) protected areas. Lynx lynx martinoi has a small, fragmented distribution with a small total population size and an endangered population. This study combines species distribution modelling with spatial prioritisation techniques to identify conservation areas for Lynx lynx martinoi. The aim was to determine locations of high probability of occurrence for the lynx, to potentially increase current protected areas by 20 % in Albania, the former Yugoslav Republic of Macedonia, Montenegro, and Kosovo. The species distribution modelling used generalised linear models with lynx occurrence and pseudo-absence data. Two models were developed and fitted using the lynx data: one based on natural factors, and the second based on factors associated with human disturbance. The Zonation conservation planning software was then used to undertake spatial prioritisations of the landscape using the first model composed of natural factors as a biological feature, and (inverted) a second model composed of anthropological factors such as a cost layer. The first model included environmental factors as elevation, terrain ruggedness index, woodland and shrub land, and food factor as chamois prey (occurrences) and had a prediction accuracy of 82 %. Second model included anthropological factors as agricultural land and had a prediction accuracy of 65 %. Prioritised areas for extending protected areas for lynx conservation were found primarily in the Albania–Macedonia–Kosovo and Montenegro–Albania–Kosovo cross-border areas. We show how natural and human factors can be incorporated into spatially prioritising conservation areas on a landscape level. Our results show the importance of expanding the existing protected areas in cross-border areas of core lynx habitat. The priority of these cross-border areas highlight the importance international cooperation can play in designing and implementing a coherent and long-term conservation plan including a species conservation plan to securing the future of the lynx.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"404 1","pages":"17-31"},"PeriodicalIF":2.2,"publicationDate":"2016-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84858675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Campos, G. Llorente, L. Rincón, Ricardo Lourenço-de-Moraes, M. Solé
Abstract. One of the most common conservation strategies used to preserve threatened species is the establishment of protected areas (PAs), providing a maximum representation of biodiversity with the smallest possible cost. The Brazilian Atlantic Forest is one of the 35 global biodiversity hotspots for conservation priorities, having high rate of habitat loss, which is one of the main factors driving threatened amphibians to extinction. Considering that amphibians are the vertebrate group with the largest number of species geographically excluded from global PAs, gap analysis was employed to evaluate whether or not the PAs of the Brazilian Atlantic Forest safeguard the threatened amphibian species in this region. Species status were compared through the official list of threatened species of the Brazilian Fauna and occurrence maps were obtained from the IUCN (International Union for Conservation of Nature) Red List database. Thirty-eight threatened amphibian species were found, accounting for 17 critically endangered (CR), 10 endangered (EN), and 11 vulnerable (VU). The PAs distributed in the Brazilian Atlantic Forest corresponds to only 9 % of the region's entire area. This protected network covers only 30 % of the total geographical range of the assessed species. Besides, a shift in Brazil's environmental policy has led to PAs downgrading. Therefore, the maintenance of PAs integrity is essential, as well as further investment is necessary for the creation of new reserves, avoiding species loss and reducing the extinction risk of the threatened amphibian species in the Brazilian Atlantic Forest.
{"title":"Protected areas network and conservation efforts concerning threatened amphibians in the Brazilian Atlantic Forest","authors":"F. Campos, G. Llorente, L. Rincón, Ricardo Lourenço-de-Moraes, M. Solé","doi":"10.5194/WE-16-9-2016","DOIUrl":"https://doi.org/10.5194/WE-16-9-2016","url":null,"abstract":"Abstract. One of the most common conservation strategies used to preserve threatened species is the establishment of protected areas (PAs), providing a maximum representation of biodiversity with the smallest possible cost. The Brazilian Atlantic Forest is one of the 35 global biodiversity hotspots for conservation priorities, having high rate of habitat loss, which is one of the main factors driving threatened amphibians to extinction. Considering that amphibians are the vertebrate group with the largest number of species geographically excluded from global PAs, gap analysis was employed to evaluate whether or not the PAs of the Brazilian Atlantic Forest safeguard the threatened amphibian species in this region. Species status were compared through the official list of threatened species of the Brazilian Fauna and occurrence maps were obtained from the IUCN (International Union for Conservation of Nature) Red List database. Thirty-eight threatened amphibian species were found, accounting for 17 critically endangered (CR), 10 endangered (EN), and 11 vulnerable (VU). The PAs distributed in the Brazilian Atlantic Forest corresponds to only 9 % of the region's entire area. This protected network covers only 30 % of the total geographical range of the assessed species. Besides, a shift in Brazil's environmental policy has led to PAs downgrading. Therefore, the maintenance of PAs integrity is essential, as well as further investment is necessary for the creation of new reserves, avoiding species loss and reducing the extinction risk of the threatened amphibian species in the Brazilian Atlantic Forest.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"18 1","pages":"9-12"},"PeriodicalIF":2.2,"publicationDate":"2016-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77505981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract. The relations between environmental gradients, as measured by 19 independent variables, and traditional diversity indices (taxonomic richness, diversity and evenness) of benthic macroinvertebrate communities in the lotic systems of northern Italy were analyzed. Redundancy analysis (RDA) was used to describe the response of taxa to environmental gradients. Diversity indices were analyzed using generalized linear models (GLMs) with explanatory variables the first two major RDA axes. The results from RDA showed that taxa variance is mostly explained by altitude/latitude and combined pollution gradients. Taxonomic richness and diversity was higher in the low polluted upland sites (LPUs) in comparison to high polluted lowland sites (HPLs), suggesting that headwater streams have higher taxonomic richness than downstream reaches. On the other hand, evenness was lower in LPUs, probably due to the dominance of some taxa (e.g., Plecoptera) that are more tolerant of colder conditions.
{"title":"Relations between environmental gradients and diversity indices of benthic invertebrates in lotic systems of northern Italy","authors":"V. Aschonitis, G. Castaldelli, E. Fano","doi":"10.5194/WE-16-13-2016","DOIUrl":"https://doi.org/10.5194/WE-16-13-2016","url":null,"abstract":"Abstract. The relations between environmental gradients, as measured by 19 independent variables, and traditional diversity indices (taxonomic richness, diversity and evenness) of benthic macroinvertebrate communities in the lotic systems of northern Italy were analyzed. Redundancy analysis (RDA) was used to describe the response of taxa to environmental gradients. Diversity indices were analyzed using generalized linear models (GLMs) with explanatory variables the first two major RDA axes. The results from RDA showed that taxa variance is mostly explained by altitude/latitude and combined pollution gradients. Taxonomic richness and diversity was higher in the low polluted upland sites (LPUs) in comparison to high polluted lowland sites (HPLs), suggesting that headwater streams have higher taxonomic richness than downstream reaches. On the other hand, evenness was lower in LPUs, probably due to the dominance of some taxa (e.g., Plecoptera) that are more tolerant of colder conditions.","PeriodicalId":54320,"journal":{"name":"Web Ecology","volume":"106 ","pages":"13-15"},"PeriodicalIF":2.2,"publicationDate":"2016-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72429509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}