基于EES-物元模型的淮南市土地生态安全评价

构造基于经济-环境-社会(EES)概念框架的土地生态安全评价指标体系,借助熵权法进行赋权,运用物元分析法构建土地生态安全综合评价模型,对淮南市作土地生态安全评价。评价结果表明:淮南市2010年、2013年和2016年的土地生态安全评价等级均为"一般安全"等级。研究可知:环境脆弱性一直是资源型城市面临的一大难题,淮南市在发展社会、经济的同时,更要致力于环境系统的绿色健康,从而提升土地生态安全等级。     

汶川县生态保护红线人类活动本底调查评估

生态保护红线是国家和区域生态安全的底线,以阿坝州汶川县划定的生态保护红线区为研究区域,利用GIS软件对研究区域内人类活动遥感影像进行遥感解译,并对研究区生态保护红线内的人类活动进行本底实地调查,结合遥感解译和实地调查结果,对红线内人类活动强度进行了评价。结果表明:红线内人类活动面积共计142.04hm²,人类活动斑块数量共计281个;红线内的人类活动影响指数为0.019,人类活动影响强度弱;红线内人类活动影响类型主要为旅游活动和耕地、道路及居民点等。     

基于灰色预测模型的土地生态安全评价

以PSR模型建立土地生态安全评价指标体系,采用熵权法定权重,运用综合评价模型评估安全等级;构建灰色预测模型测算土地生态安全指数。以湖北省为例,评价其2013—2017年土地生态安全状况,预测其2018—2022年土地生态安全状况。结论表明2013—2017年综合指数由下降转为上升趋势;预测2018—2022年湖北省安全指数呈上升趋势,达到Ⅳ级。基于分析,提出大力加强环境监管和城乡环境整治工作、强化生态环境保护、构建节约型社会等建议来改善湖北省土地生态安全状况。     

长江三峡重庆库区城镇化与生态协调性评析

长江三峡成库后，库区生态环境更加脆弱，产业空心化日益突显。随着库区移民投资的逐渐减少，库区城镇化动力已显不足。分析了库区城镇化发展与生态建设间存在的主要问题，以ARCGIS9软件为工作平台，应用多级加权求和综合评价模型进行了城镇化和生态环境的协同度评价，并以评价值为基础将研究区划分为低级——较协调、初级——较失调、中级——失调、准发展——微协调、发展——较协调5个阶段，针对各阶段提出了城镇化和生态的发展调控方向。     

新疆阿瓦提绿洲生态安全模糊综合评价

随着人类活动对区域生态环境干扰强度加大,新疆绿洲脆弱的生态环境面临更大的压力,未来绿洲生态安全风险也将剧增.而目前针对南疆绿洲生态安全的研究还较少.论文以南疆阿瓦提县绿洲为研究区,从水资源、社会经济发展和生态环境3方面构建新疆绿洲生态安全评价指标体系,采用变异系数法与层次分析法相结合计算指标权重,采用模糊综合法计算绿洲生态安全综合评分,由此判别研究区生态安全状况.评估结果表明,3个子系统对应于绿洲生态安全评价目标的权重分别为0.4936、0.1707、0.3357;1999-2011年,阿瓦提绿洲生态安全综合评分约在0.5左右,处于不安全状态,且呈现逐年下降趋势;其中水资源子系统安全度降低趋势尤为显著.论文探索了南疆绿洲生态安全状况的诊断方法,对南疆绿洲实施生态恢复与重建、改善绿洲生态安全状况具有一定实用价值.     

三峡库区消落带湿地生态过程及生态安全分析—以开县澎溪河湿地自然保护区为例

三峡库区的生态安全与长江中下游的生态环境问题有着直接关系,同时也涉及整个长江流域的可持续发展。本文从库区蓄水后形成的消落带湿地入手,对三峡库区的国土安全、水安全和生物安全等进行分析。基于以上研究,本文提出一些建议,促使消落带湿地的保护及三峡库区生态安全得以保障。     

河北省生态安全评价研究

在河北省已有的调查数据和有关统计资料的基础上,对河北省生态环境现状进行了初步分析。根据河北省生态环境的特点,以市级行政单位作为评价的基本单元,运用压力—状态—响应模型,建立了生态安全评价指标体系,运用层次分析法对河北省的生态安全现状进行综合评价。根据对河北省生态安全现状评价结果的分析,提出了确保河北省生态安全的发展对策。     

安徽省沿江地区土地生态安全评价

以安徽省沿江地区为研究对象,在对土地生态安全理论进行总结的基础上,根据研究区的实际情况,建立了土地生态安全评价指标体系,运用层次分析和信息熵等数学方法,计算了2006年研究区各市土地生态安全综合评价值.研究结果表明,芜湖市、池州市、安庆市、宣城市、巢湖市和滁州市的土地生态安全评价等级为Ⅳ级(良好);合肥市和马鞍山市的土地生态安全评价等级为Ⅲ级(一般);铜陵市的土地生态安全评价等级为Ⅱ级(较差).通过对评价结果的分析,为该区土地生态安全建设提供科学依据.     

水库库区油田勘探对环境的影响及对策

随着国民经济的发展,对石油的需求量迅猛增加,石油部门势必要不断地进行新油田勘探开发工作。在水库库区进行油田勘探开发,如不采取恰当有力的保护措施,对环境造成的影响将是严重的。以石油部门在内蒙他拉手水库库区进行的油田勘探开发为例,可以看出石油开发对库区生态及环境有如下的影响：一、油田勘探对库区环境的影响石油勘探部门近几年来在他拉于水库库区迸行了大规模无任何保护措施的石油勘探和开采活动（85％以上的探井和采油井都位于他拉干水库北岸）,对库区水资源、草场、林地和渔业等生态环境造成了严重的破坏和影响。1、库…     

河南省农业可持续发展生态安全动态评价

以河南省为研究区,依据PSR框架模型,结合河南省区域环境及土地利用特点,构建了河南省农业可持续发展的生态安全评价指标体系,采用均方差法确定了评价指标的权重,对研究区1990年、1995年、2000年、2003年、2005年、2007年、2008年7个时段的农业生态安全进行了动态综合评价。结果表明,河南省农业生态安全呈现先下降后回升态势,安全等级处于Ⅳ～Ⅴ级,安全状态从风险下降到恶化态;2003年是农业生态安全变化的转折点,从2003年起,农业生态安全有所回升。最后分析了影响河南省生态安全的主要胁迫因子,提出了农业可持续发展的生态安全建设对策。     

AN APPLICATION RUNOFF MODEL STRATEGY FOR UNGAGED WATERSHEDS1

ABSTRACT: Mathematical models for predicting watershed surface flow responses are available, most of which are elaborate nonlinear numerical surface and channel flow models linked with infiltration models. Such models may be used to make predictions for ungaged areas, assuming an acceptable fitting of the model to the topography and roughness of the real system. For some application purposes, these models are impractical because of their complexity and expensive computer solutions. A procedure is developed that uses a complex model of an ungaged area to derive a simpler parametric nonlinear system model for repetitious simulation with input sequences. The predicted flow outputs are obtained with the simpler model at significant savings of money and time. The procedures for constructing a complex kinematic model of a 40 acre (161,880 m²) reference watershed and deriving the simpler system model are outlined. The results of predictions from both models are compared with a selected set of measured events, all having essentially the same initial conditions. Peak discharges ranged from 3 to 118 ft³/sec (0.085 to 3.34 m³/sec), which includes the largest event of record. The inherent limitations of lumped systems models are demonstrated, including the bias caused by their inability to model infiltration losses after rainfall ceases. Computer costs and times for the models were compared. The derived simple model has a cost advantage when repeated use of a model is required. Such an applications hydrologic model has an engineering tradeoff of reduced accuracy, and lumping bias, but is more economical for certain design purposes.     

Conversion of temperate forests into heaths: Role of ecosystem disturbance and ericaceous plants

Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.     

BIOLOGICAL INDICATORS AND BIOLOGICAL EFFECTS OF ESTUARINE/COASTAL POLLUTION1

ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.     

Using Paleo Reconstructions to Improve Streamflow Forecast Lead Time in the Western United States

In water stressed regions, water managers are exploring new horizons that would help in long‐range streamflow forecasts. Oceanic‐atmospheric oscillations have been shown to influence streamflow variability. In this study, long‐lead time streamflow forecasts are made using a multiclass kernel‐based data‐driven support vector machine (SVM) model. The extended streamflow records based on tree ring reconstructions were used to provide a longer time series data. Reconstructed data were used from 1658 to 1952 and the instrumental record was used from 1953 to 2007. Reconstructions for oceanic‐atmospheric oscillations included the El Niño‐Southern Oscillation, Pacific Decadal Oscillation, Atlantic Multidecadal Oscillation, and North Atlantic Oscillation. Streamflow forecasts using all four oscillations were made with one‐year to five‐year lead times for 21 gages in the western United States. This is the first study that uses both instrumental and reconstructed data of oscillations in SVM model to improve streamflow forecast lead time. SVM model was able to provide “satisfactory” to “very good” forecasts with one‐ to five‐year lead time for the selected gages. The use of all the oscillation indices helped in achieving better predictability compared to using individual oscillations. The SVM modeling results are better when compared with multiple linear regression model forecasts. The findings are statistical in nature and are expected to be useful for long‐term water resources planning and management.     

Urban ecological systems: scientific foundations and a decade of progress

Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.     

Journalists' views of advertiser pressures on agricultural news

All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.     

Neighbourhood characteristics and urban gardens in the Toledo metropolitan area: staffing and voluntarism,food production,infrastructure, and sustainability practices

Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.     

Definition Procedures Have Little Effect on Performance of Environmental Classifications of Streams and Rivers

Mapped environmental classifications are defined using various procedures, but there has been little evaluation of the differences in their ability to discriminate variation in independent ecological characteristics. We tested the performance of environmental classifications of the streams and rivers of France that had been defined from the same environmental data using geographic regionalization and numerical classification of individual river valley segments. Test data comprised invertebrate assemblages, water chemistry, and hydrological indexes obtained from sites throughout France. Classification performance was measured by analysis of similarity (ANOSIM). Geometric regions defined by a regular grid and without regard to environmental variables and a posteriori classifications based on clustering the test datasets defined lower and upper bounds of performance for a given number of classes. Differences in classification performances were generally small. The ANOSIM statistics for the a posteriori classifications were around twice that of all environmental classifications, including geometrically defined regions. The hydro-ecoregions performed slightly better for the invertebrate data and the network classification performed slightly better for the chemistry and hydrological data. Our results indicate that environmental classifications that are defined using different procedures can be comparable in terms of their ability to discriminate variation of ecological characteristics and that alleged differences in performance arising from different classification procedures can be small relative to unexplained variation. We conclude that definition procedures might have little effect on the performance of large-scale environmental classifications and decisions over which procedures to use should be based primarily on pragmatic considerations.     

Predicting deer-vehicle collisions in an urban area

Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.     

Biodiversity and biotechnology

The maintenance of biodiversity is urged from many quarters and on grounds ranging from aesthetic considerations to its usefulness, particularly for biotechnology. But regardless of the grounds for preserving biodiversity, writers are generally in agreement that it should be preserved. But, in examining the various references biodiversity, such as species diversity, genetic diversity, and habitat diversity, it is apparent that we cannot aim to preserve biodiversityas such, since there are a number of conflicts in any such undertaking. In preserving one aspect of biodiversity, we damage another aspect. Five arguments which attempt to ground our moral concern for biodiversity are reviewed and critiqued, not only for their consistency but also for their power to move us to action. The final section of the paper shows how conflicts in the values of personal and environmental health can impair ethical action and especially policy formation.An earlier version of this paper was read at the conference on Agriculture, Food, and Human Values: Tradition and Change, Orlando, Florida, October 7–9, 1987.