浅议平安县生态建设与保护工作中存在的问题及对策

文章依据有关资料和实地调查,探讨分析了平安县在生态环境建设与保护工作中存在的突出问题,并针对存在的问题提出了加强生态建设与保护工作的建议。     

几种气象资料在人工增雨效果评估中的应用研究

为了在人工增雨作业后尽快地为地方政府和环保等有关部门提供作业效果评估报告,对本地新装激光雷达和雨滴谱实测资料等进行了应用分析。结果表明,激光雷达探测的云光学厚度实况资料与卫星反演资料差异不大,在作业指挥和较大范围增雨作业的效果评估中均可应用,高时间精度的雨滴谱资料用于人工增雨效果评估较为快捷、直观、方便。这两种新资料的应用可填补日常观测资料在缺测时的不足,其评估结果能及时为环保等部门治理污染提供参考。     

关于《干燥箱》国家标准制定技术问题的讨论

在《干燥箱》国家标准制订过程中,根据企业多年的实践和对相关资料的分析,对温度均匀度、升温时间、测量与计算方法等多个技术问题进行了探讨,望有助于标准的完善和理解。     

基于Matlab的神经网络在绵阳空气质量预测中的应用

以绵阳市2014～2016年空气污染指数(API)以及SO_2、NO_2、PM_(10)等污染物为研究对象,探讨了绵阳市空气污染的变化规律,并分析它们与常规观测的地面气象资料之间的关系。尝试采用多元线性回归方法及BP神经网络方法建立污染预报模型,并检验分析两种模型的可行性。结果表明基于BP神经网络的预报模型在污染预报中可行,并建立基于BP神经网络进行空气质量预测的预测模型,利用历史资料进行验证。     

优质春播小麦99-5产量与气象影响因子回归分析

利用春播优质小麦99-5分期播种产量资料与同期气象资料进行回归分析,结果表明,小麦产量的高低与播种-抽穗期的积温、抽穗-开花期的日照和开花-成熟期的相对湿度呈显著相关.     

印度汉干河的污染研究及污染的生物评价

对于印度汉干河的污染研究,其重点是放在对水质的生物评价上。本研究襄括精密的分析;在印度汉干河环境条件中,对欧洲多种用于水污染的生物监测方法进行了尝试;研究中将此河分成几个不同的污染带。将生物资料与化学资料联系起来,讨论了在印度环境中欧洲污水生物系统的实际内含物。同时还讨论了在河流水质评价中,水生大型无脊椎动物的重要性。     

农村污水收集系统的探讨

目前我国大多农村污水没有进行收集处理而是直接排放到附近的河流中,造成农村环境恶化。由于我国农村排水方面基础资料缺乏,导致农村排水系统建设速度缓慢。收集我国农村排水方面的基础资料,分析区域特点,提供不同的污水收集方式和处理方式的选择要素,对合理利用水资源、促进农村的可持续发展具有极为重要的意义。本文从自然地理条件、经济与社会条件、风俗习惯等角度介绍了如何根据地域特点选择农村污水收集的方式与处理方法。     

基于颗粒物激光雷达的南充市一次沙尘污染过程分析

利用环境空气颗粒物自动监测数据、近地面气象数据和颗粒物激光雷达资料对南充市主城区2016年5月12日的沙尘气溶胶污染天气过程进行分析,并利用HYSPLIT模式对沙尘气溶胶的来源进行了模拟分析。结果表明:来自新疆盆地的沙尘气溶胶经高空远距离输送到达四川盆地上空后沉降造成南充市主城区的PM_(10)和PM_(2.5)浓度极显著升高,PM_(2.5)/PM_(10)值极显著降低;沙尘天气过程中,风速、气温、相对湿度、气压、能见度和大气边界层高度等气象因子发生变化并对环境空气中颗粒物浓度产生影响,其中风速与PM_(2.5)和PM_(10)浓度间显著正相关,与PM_(2.5)/PM_(10)值间显著负相关;颗粒物激光雷达连续监测到整个沙尘气溶胶沉降过程,与地面环境空气自动监测数据变化趋势一致。在对盆地城市沙尘天气的环境空气质量进行预警预报时,将历史环境空气质量自动监测数据与常规气象因子数据、颗粒物雷达资料和后向轨迹等资料进行综合分析,能进一步提高沙尘天气条件下的空气质量预警预报准确度。     

湿地生态系统基质重金属积累与酶活性的研究现状

湿地生态系统具有净化污水的功能,因其具有高效低耗等优点,在污水处理方面极具开发应用前景,而基质作为湿地生态系统重要组成部分,已成为众多学者的研究热点。本文综合分析了湿地生态系统基质中重金属积累和酶活性的时空分布及影响因素的研究现状,并对相关研究提出了新的认识与展望,以期为湿地生态系统基质去除废水中重金属的深入研究和应用提供综合分析资料。     

瓦里关山TSP浓度分布特征及与大气污染物排放的关系

本文利用瓦里关山2003—2004年监测的TSP浓度资料，分析其浓度值的时间分布特征，讨论了浓度值分布与风场的相关关系；分析瓦里关山周围大气污染物中烟尘、粉尘排放情况，对大气污染物中烟尘粉尘排放对瓦里关山TSP浓度值的影响程度进行了探讨，得到了关于高原相对清洁区TSP分布的一些有意义的研究结果。     

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.