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971.
We compiled 46 broadscale data sets of species richness for a wide range of terrestrial plant, invertebrate, and ectothermic vertebrate groups in all parts of the world to test the ability of metabolic theory to account for observed diversity gradients. The theory makes two related predictions: (1) In-transformed richness is linearly associated with a linear, inverse transformation of annual temperature, and (2) the slope of the relationship is near -0.65. Of the 46 data sets, 14 had no significant relationship; of the remaining 32, nine were linear, meeting prediction 1. Model I (ordinary least squares, OLS) and model II (reduced major axis, RMA) regressions then tested the linear slopes against prediction 2. In the 23 data sets having nonlinear relationships between richness and temperature, split-line regression divided the data into linear components, and regressions were done on each component to test prediction 2 for subsets of the data. Of the 46 data sets analyzed in their entirety using OLS regression, one was consistent with metabolic theory (meeting both predictions), and one was possibly consistent. Using RMA regression, no data sets were consistent. Of 67 analyses of prediction 2 using OLS regression on all linear data sets and subsets, two were consistent with the prediction, and four were possibly consistent. Using RMA regression, one was consistent (albeit weakly), and four were possibly consistent. We also found that the relationship between richness and temperature is both taxonomically and geographically conditional, and there is no evidence for a universal response of diversity to temperature. Meta-analyses confirmed significant heterogeneity in slopes among data sets, and the combined slopes across studies were significantly lower than the range of slopes predicted by metabolic theory based on both OLS and RMA regressions. We conclude that metabolic theory, as currently formulated, is a poor predictor of observed diversity gradients in most terrestrial systems.  相似文献   
972.
Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to a variety of assumptions that are difficult to meet or to apply to evolutionary timescales. Furthermore, such methods cannot be rigorously applied to high-gene-flow species. Here, we employ genetic parentage assignments in conjunction with demographic simulations to infer the level of immigration into a putative sink population. We use individual-based demographic models to estimate expected distributions of parent-offspring dyads under competing sink and closed-population models. By comparing the actual number of parent-offspring dyads (identified from multilocus genetic profiles) in a random sample of individuals taken from a population to expectations under these two contrasting demographic models, it is possible to estimate the rate of immigration and test hypotheses related to the role of immigration on population processes on an ecological timescale. The difference in the expected number of parent-offspring dyads between the two population models was greatest when immigration into the sink population was high, indicating that unlike traditional population genetic inference models, the highest degree of statistical power is achieved for the approach presented here when migration rates are high. We used the proposed genetic parentage approach to demonstrate that a threatened population of Marbled Murrelets (Braclhyrarmphus marmotus) appears to be supplemented by a low level of immigration (approximately 2-6% annually) from other populations.  相似文献   
973.
Habitat fragmentation lowers survival of a tropical forest bird.   总被引:1,自引:0,他引:1  
Population ecology research has long been focused on linking environmental features with the viability of populations. The majority of this work has largely been carried out in temperate systems and, until recently, has examined the effects of habitat fragmentation on survival. In contrast, we looked at the effect of forest fragmentation on apparent survival of individuals of the White-ruffed Manakin (Corapipo altera) in southern Costa Rica. Survival and recapture rates were estimated using mark-recapture analyses, based on capture histories from 1993 to 2006. We sampled four forest patches ranging in size from 0.9 to 25 ha, and four sites in the larger 227-ha Las Cruces Biological Station Forest Reserve (LCBSFR). We found a significant difference in annual adult apparent survival rates for individuals marked and recaptured in forest fragments vs. individuals marked and recaptured in the larger LCBSFR. Contrary to our expectation, survival and recapture probabilities did not differ between male and female manakins. Also, there was no support for the existence of annual variation in survival within each study site. Our results suggest that forest fragmentation is likely having an effect on population dynamics for the White-ruffed Manakin in this landscape. Therefore, populations that appear to be persisting in fragmented landscapes might still be at risk of local extinction, and conservation action for tropical birds should be aimed at identifying and reducing sources of adult mortality. Future studies in fragmentation effects on reproductive success and survival, across broad geographical scales, will be needed before it is possible to achieve a clear understanding of the effects of habitat fragmentation on populations for both tropical and temperate regions.  相似文献   
974.
This paper describes the environmental indicators GIS of the Catalan coast, Spain. The spatial data model is based on vector and raster layers with three main modules: the biodiversity, the general biophysical and the socioeconomic. Presently, the database has a number of pressure and impact indicators that have been used to model the components and structure of the system and are suggested to build ecological resilience. Special interest has been given to the analysis of functional groups of species that are relevant to the dynamics of the coastal system, and preliminary results are presented. This system constitutes a user-oriented analytical and monitoring tool for coastal zone managers and researchers. Although, the system is under development it is expected that resulting spatial indicators of environmental condition can be used to promote more sustainable coastal strategies and actions in the Catalan coast.  相似文献   
975.
We review the current state of knowledge about urban ecosystem services in New York City (NYC) and how these services are regulated, planned for, and managed. Focusing on ecosystem services that have presented challenges in NYC—including stormwater quality enhancement and flood control, drinking water quality, food provisioning and recreation—we find that mismatches between the scale of production and scale of management occur where service provision is insufficient. Adequate production of locally produced services and services which are more accessible when produced locally is challenging in the context of dense urban development that is characteristic of NYC. Management approaches are needed to address scale mismatches in the production and consumption of ecosystem services. By coordinating along multiple scales of management and promoting best management practices, urban leaders have an opportunity to ensure that nature and ecosystem processes are protected in cities to support the delivery of fundamental urban ecosystem services.  相似文献   
976.
The insecticide chlordecone is a contaminant found in most of the banana plantations in the French West Indies. This study aims to search for fungal populations able to grow on it. An Andosol heavily contaminated with chlordecone, perfused for 1 year in a soil–charcoal system, was used to conduct enrichment cultures. A total of 103 fungal strains able to grow on chlordecone-mineral salt medium were isolated, purified, and deposited in the MIAE collection (Microorganismes d'Intérêt Agro-Environnemental, UMR Agroécologie, Institut National de la Recherche Agronomique, Dijon, France). Internal transcribed spacer sequencing revealed that all isolated strains belonged to the Ascomycota phylum and gathered in 11 genera: Metacordyceps, Cordyceps, Pochonia, Acremonium, Fusarium, Paecilomyces, Ophiocordyceps, Purpureocillium, Bionectria, Penicillium, and Aspergillus. Among predominant species, only one isolate, Fusarium oxysporum MIAE01197, was able to grow in a liquid culture medium that contained chlordecone as sole carbon source. Chlordecone increased F. oxysporum MIAE01197 growth rate, attesting for its tolerance to this organochlorine. Moreover, F. oxysporum MIAE01197 exhibited a higher EC50 value than the reference strain F. oxysporum MIAE00047. This further suggests its adaptation to chlordecone tolerance up to 29.2 mg l?1. Gas chromatography–mass spectrometry (GC-MS) analysis revealed that 40 % of chlordecone was dissipated in F. oxysporum MIAE01197 suspension culture. No chlordecone metabolite was detected by GC-MS. However, weak amount of 14CO2 evolved from 14C10-chlordecone and 14C10-metabolites were observed. Sorption of 14C10-chlordecone onto fungal biomass followed a linear relationship (r 2?=?0.99) suggesting that it may also account for chlordecone dissipation in F. oxysporum MIAE01197 culture.  相似文献   
977.
The effects of atmospheric pollutants and climatic conditions were studied in a decayed column in the Seminary of Sant Pere. This nineteenth-century building is situated in the historic centre of Palma (Mallorca, Spain), less than 0.5 km from the sea. Samples were collected from the internal and external part of the crusts formed in the four sides of the column. The samples were analysed by means of thermal analysis, X-ray diffractometry, scanning electron microscopy, Fourier transform infrared spectroscopy and ion chromatography. Results show significant differences in the four sides of the column. A high degree of carbonate stone sulfation is observed in all of the samples analysed. A synergistic effect between atmospheric factors and micropollutants on the deterioration of stone is observed. A high uptake of atmospheric particulate matter is found in the external part of the black crusts.  相似文献   
978.
Agro-food, petroleum, textile, and leather industries generate saline wastewater with a high content of organic pollutants such as aromatic hydrocarbons, phenols, nitroaromatics, and azo dyes. Halophilic microorganisms are of increasing interest in industrial waste treatment, due to their ability to degrade hazardous substances efficiently under high salt conditions. However, their full potential remains unexplored. The isolation and identification of halophilic and halotolerant microorganisms from geographically unrelated and geologically diverse hypersaline sites supports their application in bioremediation processes. Past investigations in this field have mainly focused on the elimination of polycyclic aromatic hydrocarbons and phenols, whereas few studies have investigated N-aromatic compounds, such as nitro-substituted compounds, amines, and azo dyes, in saline wastewater. Information regarding the growth conditions and degradation mechanisms of halophilic microorganisms is also limited. In this review, we discuss recent research on the removal of organic pollutants such as organic matter, in terms of chemical oxygen demand (COD), dyes, hydrocarbons, N-aliphatic and N-aromatic compounds, and phenols, in conditions of high salinity. In addition, some proposal pathways for the degradation of aromatic compounds are presented.  相似文献   
979.
Environmental Science and Pollution Research - This study provides an analysis of the spatial distribution and trends of NO, NO2 and O3 concentrations in Portugal between 1995 and 2010....  相似文献   
980.
This paper assesses land-use changes related to naturbanization processes on three biosphere reserves in Southern Europe. A comparative analysis has been done on the National Parks in Peneda-Gerês in North Portugal, Cévennes in South France and Sierra Nevada in South Spain, using Corine Land Cover data from 1990 until 2006. Results indicate that the process of land-use intensification is taking place in the frame of naturbanization dynamics that could jeopardize the role of Protected Areas. Focusing on the trends faced by National Parks and their surrounding territories, the analysis demonstrates, both in quantitative and spatial terms, the intensification processes of land-use changes and how it is important to know them for coping with increasing threats. The article concludes that in the current context of increasing stresses, a broader focus on nature protection, encompassing the wider countryside, is needed if the initiatives for biodiversity protection are to be effective.  相似文献   
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