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91.
Application of remote sensing and Geographic Information System (GIS) as a tool has assumed an immense significance in habitat suitability modelling for various wildlife species and now a days these are widely used in conservation biology and wildlife management.  相似文献   
92.
Abstract:  Models of species' distributions are commonly used to inform landscape and conservation planning. In urban and semiurban landscapes, the distributions of species are determined by a combination of natural habitat and anthropogenic impacts. Understanding the spatial influence of these two processes is crucial for making spatially explicit decisions about conservation actions. We present a logistic regression model for the distribution of koalas (  Phascolarctos cinereus ) in a semiurban landscape in eastern Australia that explicitly separates the effect of natural habitat quality and anthropogenic impacts on koala distributions. We achieved this by comparing the predicted distributions from the model with what the predicted distributions would have been if anthropogenic variables were at their mean values. Similar approaches have relied on making predictions assuming anthropogenic variables are zero, which will be unreliable if the training data set does not include anthropogenic variables close to zero. Our approach is novel because it can be applied to landscapes where anthropogenic variables are never close to zero. Our model showed that, averaged across the study area, natural habitat was the main determinant of koala presence. At a local scale, however, anthropogenic impacts could be more important, with consequent implications for conservation planning. We demonstrated that this modeling approach, combined with the visual presentation of predictions as a map, provides important information for making decisions on how different conservation actions should be spatially allocated. This method is particularly useful for areas where wildlife and human populations exist in close proximity.  相似文献   
93.
The main objective of this study is to simulate the potential vegetation types on the basis of environmental parameters.The paper took Barkam County in a mountainous region of the Eastern Tibetan Plateau as the study area.The vegetation distribution was mapped in 1994 and 2007 based on TM remote sensing images by object-oriented interpretation method.We overlaid the two maps to find out the vegetation patches which have not changed,and took them as stable types.Fifty per cent of the stable patches were randomly sampled to operate the logistic regression with related environmental parameters;others were used as test data of simulated results.Seven environmental parameters were mapped,including elevation,slope,aspect,surface curvature,solar radiation,temperature and precipitation,based on DEM data and meteorological site data by GIS technology.The relationship between the spatial distribution of vegetation and environmental variables were quantified by logistic regression.The distribution probabilities of each vegetation type were calculated.Finally,the spatial distribution of potential vegetation was simulated.This research can provide a scientific basis for vegetation restoration and ecological construction in this area.  相似文献   
94.
The sludge from a steel processing unit bearing zinc, lead, iron, and manganese was solidified with ordinary Portland cement. The waste was stabilized in the specimens with a waste/binder ratio range of 0.16–4.0. On the basis of the available leaching and unconfined compressive strength, the performance of the solidified/stabilized waste was compared for different numbers of curing days. It was found that curing up to 28 days resulted in a performance improvement, as shown by less leaching of heavy metals and the increased unconfined compressive strength of the specimen. The treatment effectiveness of the solidification/stabilization process was assessed for the metals Pb, Zn, Fe, and Mn, and was found to be 89%, 95%, 74%, and 90%, respectively, for an optimum ratio of 4.0 after 28 days of curing.  相似文献   
95.
This article presents the findings of the first major visitor survey conducted at the Central Rhodope Mountain Complex, situated in northern Greece. The study area is one of a number of sites planned to become National Parks under a recent initiative of the Greek government. We used a logistic regression method to define significant predictors of visitors’ awareness and attitude toward park designation, as well as their willingness to pay a conditional entrance fee. Study findings demonstrated that the probability of being aware of the park designation initiative is higher for visitors who obtained information from travel agencies or media to make their destination choice, compared to visitors who resorted to word-of-mouth recommendations. Knowledge and attitudes toward animals living in the study area revealed a limited influence on visitors’ dispositions toward park designation. The results of this study call for action to implement education programs for National Park users. These programs should aim at rendering the environmental characteristics of the Central Rhodope Mountain Complex to be significant predictors of visitors’ dispositions toward the study area. This would favor its uniqueness as a destination, as well as contribute to its long-term economic sustainability.  相似文献   
96.
Efficient and reliable unexploded ordnance (UXO) site characterization is needed for decisions regarding future land use. There are several types of data available at UXO sites and geophysical signal maps are one of the most valuable sources of information. Incorporation of such information into site characterization requires a flexible and reliable methodology. Geostatistics allows one to account for exhaustive secondary information (i.e.,, known at every location within the field) in many different ways. Kriging and logistic regression were combined to map the probability of occurrence of at least one geophysical anomaly of interest, such as UXO, from a limited number of indicator data. Logistic regression is used to derive the trend from a geophysical signal map, and kriged residuals are added to the trend to estimate the probabilities of the presence of UXO at unsampled locations (simple kriging with varying local means or SKlm). Each location is identified for further remedial action if the estimated probability is greater than a given threshold. The technique is illustrated using a hypothetical UXO site generated by a UXO simulator, and a corresponding geophysical signal map. Indicator data are collected along two transects located within the site. Classification performances are then assessed by computing proportions of correct classification, false positive, false negative, and Kappa statistics. Two common approaches, one of which does not take any secondary information into account (ordinary indicator kriging) and a variant of common cokriging (collocated cokriging), were used for comparison purposes. Results indicate that accounting for exhaustive secondary information improves the overall characterization of UXO sites if an appropriate methodology, SKlm in this case, is used.  相似文献   
97.
In many European mountain regions, natural forest regrowth on abandoned agricultural land and the related consequences for the environment are issues of increasing concern. We developed a spatial statistical model based on multiple geophysical and socio-economic variables to investigate the pattern of natural forest regrowth in the Swiss mountain area between the 1980s and 1990s. Results show that forest regrowth occurred primarily in areas with low temperature sum, intermediate steepness and soil stoniness as well as close to forest edges and relatively close to roads. Model results suggest that regions with weak labor markets are favored in terms of land abandonment and forest regrowth. We could not find an effect of population change on land abandonment and forest regrowth. Therefore, we conclude that decision makers should consider non-linearities in the pattern of forest regrowth and the fact that labor markets have an effect on land abandonment and forest regrowth when designing measures to prevent agricultural land abandonment and natural forest regrowth in the Swiss mountains.  相似文献   
98.
ABSTRACT: This work establishes an industrial water demand (IWD) model for a short term estimate, which considers water reuse technologies and discharge regulations, for the integrated circuit (IC) industry in northern Taiwan. Based on the optimization of an industrial water cost system, a computerized system dynamics model (SD model) is developed to generate individual firm IWD using data from year 2000. A market IWD is further constructed for 25 1C firms in the study area and is approximated by an inverse logistic curve. Analytical results demonstrate that price elasticity varies with water price in cases involving water reuse.  相似文献   
99.
潘护林  陈惠雄 《中国环境管理》2021,13(1):156-161,148
深入揭示生态环境与居民幸福感的内在关系对创造人民美好生活具有重要的理论与现实意义。本研究基于幸福感产生机制对生态环境影响居民幸福感的机制进行了深入的理论探讨,利用2013-2014年我国居民大样本调查数据,定量分析了水、大气,绿化三个关键生态环境要素对我国居民幸福感的影响。研究认为,生态环境对居民幸福感的影响受制于经济发展与居民收入水平及居民对环境价值的认知与重视程度;尽管研究期居民对生态环境质量满意度不高,但生态环境对我国居民幸福感的并没造成显著影响;比较而言,水环境对居民幸福感的影响小于空气环境,而空气环境的影响又小于绿化环境。为提升我国居民生态幸福感并激励居民亲环境行为,应通过科普教育切实提高居民对环境及其价值的认知度,努力营建人地和谐的文化氛围;应在普遍提高居民收入和物质生活水平的基础上,引导和促进居民向环境审美消费需求的升级;当前应重视生态补偿等经济手段的运用,通过影响居民经济利益激发居民环保行为;应优先解决居民直观感知明显且反映强烈的环境问题。  相似文献   
100.
基于TM遥感影像、城市规划图等数据,利用logistic CA模型,模拟了2005~2010年天津市滨海新区城市形态演化,经过模拟面积和Lee Sallle指数两个指标的精度评价后,定量分析了新版总规实施后城市形态演化的驱动力。实证研究表明:滨海新区城市形态扩展迅速,驱动力大小依次是自然环境、经济发展、交通带动、城市规划引导;其中交通驱动力中,影响最强烈的依次是火车站、城市的道路、高速出入口、县乡道、航道、省道。因此提出:城市规划必须顺应城市形态发展的规律,把握好可控的关键驱动力,科学预测城市形态发展和提出城市规划方案,做到积极有效的引导城市形态发展  相似文献   
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