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741.
Iwao's quadratic regression or Taylor's Power Law (TPL) are commonly used to model the variance as a function of the mean for sample counts of insect populations which exhibit spatial aggregation. The modeled variance and distribution of the mean are typically used in pest management programs to decide if the population is above the action threshold in any management unit (MU) (e.g., orchard, forest compartment). For nested or multi-level sampling the usual two-stage modeling procedure first obtains the sample variance for each MU and sampling level using ANOVA and then fits a regression of variance on the mean for each level using either Iwao or TPL variance models. Here this approach is compared to the single-stage procedure of fitting a generalized linear mixed model (GLMM) directly to the count data with both approaches demonstrated using 2-level sampling. GLMMs and additive GLMMs (AGLMMs) with conditional Poisson variance function as well as the extension to the negative binomial are described. Generalization to more than two sampling levels is outlined. Formulae for calculating optimal relative sample sizes (ORSS) and the operating characteristic curve for the control decision are given for each model. The ORSS are independent of the mean in the case of the AGLMMs. The application described is estimation of the variance of the mean number of leaves per shoot occupied by immature stages of a defoliator of eucalypts, the Tasmanian Eucalyptus leaf beetle, based on a sample of trees within plots from each forest compartment. Historical population monitoring data were fitted using the above approaches.  相似文献   
742.
The goal of the present work is to assess the adverse effects of soil bound polycyclic aromatic hydrocarbons (PAH) which remain in soils after biological remediation. We focus on risk assessment for mammalian species with respect to the oral uptake of contaminated soil particles and compare the results of a biomarker test with those of an ecotoxicological assay, the bioluminescence inhibition test withVibrio fischeri. As a biomarker effect in mammals, we determined the liver microsomal cytochrome P450 enzyme CYP1A1 which is induced by PAH in exposed rats. After biological soil treatment, different amounts of PAH remain in the soil depending on the soil properties and initial pollutant composition. Particularly, higher condensated PAH resists biological treatment due to its hydrophobicity. In addition, high amounts of organic carbon in the soils affect remediation efficiency. In the bioluminescence inhibition test, eluates of all biologically treated soils studied do not reveal any or only low inhibitory effects. In contrast, the oral uptake of biologically treated contaminated soils leads to induction levels for CYP1A1 similar to those in the untreated samples. A good correlation is obtained between CYP1A1 levels and the amount of 5 and 6-ring PAH in the soil samples. The main result is that the remediation efficiency determined by the luminescence test is not reflected by the biomarker test, a finding which indicates the high bioavailability of residual PAH in soils. Consequently, new criteria for human risk assessment can be delineated.  相似文献   
743.
The chemical composition of water conditioned by colonies ofMoina macrocopa and involved in the regulation of their life cycle was analyzed in comparison with water samples from natural water bodies. Dechlorinated tap water was used as the control medium. The results showed that metabolism of crustaceans leads to an increase in the concentrations of phosphorus and nitrogen in all forms, the appearance of protein and carbohydrate fractions, and changes in the composition of lipid fractions in the water conditioned by their colonies. The contents of all organic components are very low, which makes their identification difficult. Concentrations of substances identified in the conditioned water do not exceed those occurring in nature.  相似文献   
744.
745.
The index of cenotic significance and other indices calculated on its basis were used for revealing specific structural features of zooplanktonic communities in lakes differing in productivity. The results showed that new indices (complexity coefficient, index of cenotic significance of dominant species, and integrated cenotic significance of the zooplankton) strongly correlate with the trophic status of the water body and are more responsive to changes in the structure of the community than the Shannon–Weaver index of species diversity. The results confirm the hypothesis that the structure of zooplankton is simplified in the course of lake eutrophication.  相似文献   
746.
For the indigenous populations of Amazonia, invertebrates constitute an important component of the diet. We have information on entomophagy for 39 ethnic groups, about 21,4 per cent of the 182 groups known in the Amazon Basin, but the use of this non conventional food resource is probably much more widespread. We present here a data-base of all the information available for each ethnic group regarding the species included in the diet, the scientific and the ethno name if known, the stage of life-cycle consumed, the manner of preparation and, when known, the host plant. This data-base lists 115 species scientifically identified and 131 ethno names. In addition, we have information about other 384 ethno names, with unsecure link to the Linnean taxonomy suggesting that local knowledge is very extensive. The data-base represents not only an easy to consult resource, but also a support for further research. The knowledge of the relations between indigenous populations and ecosystem is indeed the base for the natural and cultural biodiversity preservation.  相似文献   
747.
Russian Journal of Ecology - Abstract—The study of the effect of mycorrhiza symbiosis on the transformation of carbon and nitrogen compounds in soils is important in view of the necessity to...  相似文献   
748.
Russian Journal of Ecology - A simultaneous analysis of the chronographic variation of the mandible of bank vole (Clethrionomys glareolus Shreb.) in three longitudinally distant populations that...  相似文献   
749.
Yang  W.  Deng  D. G.  Meng  X. L.  Zhang  S. 《Russian Journal of Ecology》2019,50(4):352-360
Russian Journal of Ecology - Temporal and spatial variations of phytoplankton community in Lake Erhai were investigated from May 2010 to April 2011. A total of 124 species belonging to 8 phyla and...  相似文献   
750.
Heat waves and heat-related stresses are increasing environmental concerns in urban areas. The impact of heat waves is dependent on the intensity and duration of each event and on underlying environmental and socio-demographic factors which influence population vulnerability. In order to develop effective adaptation strategies, it is important to develop a method to clearly identify the most vulnerable areas based on these factors. The purpose of this study is to develop and map a heat wave vulnerability index combined with heat exposure analysis to identify areas where interventions can be targeted. The vulnerability index was derived from a principle component analysis of eight key variables that influence heat wave vulnerability. Eight proxy measures of vulnerability were obtained from 2010 census and land-use data for the 1904 census districts of Osaka City. Three principle components explained >77 % of the variance (age, employment and education; social isolation; density and lack of green space). The components were combined and weighted to produce a vulnerability score for each census district. The vulnerability scores ranged from 0 to 106, were categorised into eight vulnerability levels and were overlaid with fine-scale air temperature observations. The resulting output identified the distribution of population vulnerability and exposure. This assessment of vulnerability, combining exposure and sensitivity components, can provide precedent for efficient, targeted action to be taken to reduce the impact of heat waves at present and under climate change.  相似文献   
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