湖面蒸发量测算的思考─与有关专家商榷

在测站用隔热蒸发器测定水面、水生植物、盐水蒸发，只代表测站这个小环境；用更简便的仪器靠近湖泊观测，与测站同步资料相对照；最后把测站资料转移到湖面上。     

焉耆盆地石油开发对水土环境的影响

宝浪苏木构造带、本布图构造带石油勘探开发区位于新疆焉言盆地中博斯腾湖西，面积约300km2。油田开发区大部位于博湖、焉着两绿洲农田中，该油田开发除占地影响外，已对周围地区土壤、植被和水体产生有害影响，在1996年6月环境影响评价调查时证明，宝1井井场土壤已受石油严重污染，污染指数达77，井场周围土壤石油含量已高出当地背景值；井场边缘土壤中Cr含量也已高出背景值首量；污染指数0．7一G．9之间。原油大量泄漏时可能有导致地下水污染，最终影响博斯腾湖水水质。若出现井喷等重大事故，不但会造成当地水上污染，还可能导致博斯腾湖污染，影响下游孔雀河水水质。     

柴达木盆地气候变化对生态环境的影响

利用累积距平等方法对柴达木盆地近46年（1961～2006年）气温、降水和径流量资料进行了分析，探讨了盆地气候变化特征及其对生态环境的影响。结果显示：柴达木盆地近46年来气温增幅明显，降水呈略多趋势，径流呈减少趋势，区域内土地荒漠化面积大，植被覆盖率低。气候变暖、大风多、降水少、蒸发强是影响该区生态环境建设和改善的主要自然原因之一。     

博斯腾湖流域生态管理与监督措施初探

近40a来,随着人类社会经济活动强度的不断加大,大量的工农业废水排入博斯腾湖,导致博斯腾湖水体咸化、水质变坏,湖区水生生物以及湿地受到严重影响。为了减轻或避免博斯腾湖流域的生态环境继续遭受破坏,充分地实现博斯腾湖生态、经济及社会功能,必须加强博斯腾湖流域生态环境的监督与管理,采取有效的生态管理与监督措施,协调人与自然的关系。     

滇池草海东风坝水域生态修复技术工程应用

本文介绍了我院最新开发的湖泊生态修复集成技术包括湖滨陡坎沿岸带基底修复技术、植物浮岛生态技术、入湖河渠污染控制技术和湖滨沿岸带大型水生植物群落恢复技术在滇池草海东风坝及老干鱼塘水域生态修复工程的实际应用情况，本项目在滇池草海约3．3km。水面实现了大型水生植物恢复面积约1．0km^2，在湖滨带形成由挺水植物、浮叶植物、浮水植物及沉水植物等不同植被类型组成的生态结构，大型水生植物覆盖率达30％，恢复水生植物共计20余种，栖息的水禽及鸟类目前已达27种，生物多样性显著提高，呈现出郁郁葱葱、生机勃勃的景象，生态修复区良性水生植被生态系统已经初步建立，湖泊自然生态环境和水质得到了明显改善，水体透明度增幅约为65％-70％，TN和TP去除率约为30％，取得了良好的环境和社会效益，为滇池及超富营养化湖泊的生态修复提供了宝贵的经验和工程示范。     

干旱区荒漠植被的特点及恢复问题的研究--以塔里木河流域胡杨林生态系统为例

干旱区除存在唯一的真正森林-胡杨(Populuseuphratica)林外,植被普遍极其稀疏,以降水稀少,蒸发显著为特点的干旱区,荒漠植被的存在对于生态环境的保护和良性发展起到极大的作用,干旱区的荒漠植被表现出特有的生理特征,本文研究塔里木河流域胡杨林的特征及对生态环境的适应规律,进一步提出了扩展荒漠植被的可能性及其措施。     

湖面蒸发量测算的思考：与有关专家商榷

在测站用隔热蒸发器测定水面，水生植物，盐水蒸发，只代表测站这个小环境，用更简便的仪器靠近湖泊观测，与测站同步资料相对照，最后把测站资料转移到湖面上。     

邛海的生态环境现状及保护对策

文章论述了邛海生态环境现状，一是水面锐减，二是水质污染；分析了造成水面锐减的原因，首先是水土流失造成的湖库淤积，其次是围海造田、围海养殖出现的蚕食水面；水质污染的原因是无计划地发展餐饮娱乐业出现的新增污染源；最后提出必须用生态学原理寻求保护对策。     

基于Landsat-8数据的博斯腾湖透明度反演

透明度是湖泊水体重要的物理参数之一,是水体光学组分的综合反映,对研究湖泊生态环境具有重要科学意义。目前,利用遥感技术手段对博斯腾湖进行大范围、连续的水透明度监测研究相对较少。基于湖泊透明度实测值、对应点的光谱数据和Landsat-8遥感影像,分析透明度敏感波段及其组合,建立博斯腾湖水体透明度遥感反演模型。实测光谱分析结果显示波段比值运算和和差组合运算的敏感性较高,相关系数可达0.8以上;Landsat-8 OLI遥感数据分析结果得到波段比值(近红外波段和蓝色波段的比值)的敏感性较高,相关系数可达0.7;基于OLI近红外波段B5和蓝色波段B1比值的线性模型反演效果最好,精度较高,且稳定性较好。博斯腾湖透明度在200 cm左右,透明度由西向东先升高再降低,呈带状分布。     

利用大型水生植物控制水体富营养化

利用大型水生植物控制水体富营养化是一种很有前景的生态修复技术。本文从大型水生植物对藻类的抑制作用和对水体中氮、磷的去除作用2方面综述了相关研究,并对今后的研究进行了展望。     

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.     

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.     

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.     

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.     

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.     

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.     

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.     

MANGANESE CYCLE IN IMPOUNDMENT WATER

Manganese entering impounded water will undergo a cyclic transformation. Oxidation precipitates manganese from top waters. At the bottom of the lake, biological activity will render manganese soluble by both intracellular as well as extracellular activity. The study was made to demonstrate that biological reduction and transformation, organometallic complexation, together with the presence of carbon dioxide and the lowering of pH all have some effect on the solubility of manganese. Dissolved manganese may be brought back to top waters during the lake overturn and therefore deteriorates the water quality.     

Provincial development plans in Zimbabwe: an analysis of their content,structure and methodology

Zimbabwean provincial plans were instituted to help in the achievement of the national goal of the creation of an egalitarian, socialist and integrated society. The national goal itself was adopted as an antithesis to the dualist society characterised by spatial, economic, social, politican and technological inequalities that Zimbabwe inherited from colonialism. This meant that provincial plans had to play both a functional (or growth allocating/distribution) and a territorial (or redistribution) role.

This paper reviews their role in achieving the national goal by examining their functions, content, structure and methodology. The paper concludes that because of their nature, provincial plans are not suitable tools for the achievement of the national goal.