中国海洋渔业综合效益评价及耦合协调发展研究

基于综合效益评价模型和耦合协调模型,研究了2006—2015年我国沿海省区海洋渔业综合效益及子系统耦合协调度的演变规律,并运用多元回归模型分析其影响因素。结果表明:(1)我国海洋渔业综合效益呈波动上升趋势,由2006年的1.276上升到2015年的1.356,辽宁、江苏、浙江、福建、山东高于全国平均水平。(2)海洋渔业综合效益子系统耦合度水平以高水平耦合为主。(3)海洋渔业综合效益子系统协调发展水平由2006年的0.628上升到2015年的0.646,且以初级协调和中级协调为主,协调水平提升空间较大。(4)海洋经济发展水平、政府扶持力度、对外开放水平对海洋渔业综合效益子系统协调度的提升产生显著正向影响,其他影响因素对其产生正向影响但不显著。     

再生性资源型城市工业高质量发展水平评价——以徐州市为例

基于修正熵权法,以再生性资源型城市徐州市为例,分析了2000—2017年徐州市工业高质量发展演变特征。结果表明:(1)徐州市工业高质量发展水平整体上呈提高态势,但阶段性明显。(2)徐州市工业高质量发展水平是结构优化、发展效益、环境效率、创新能力等多种要素共同作用的综合表征,但各要素贡献程度呈发展效益创新能力结构优化环境效率的特点。(3)徐州市工业高质量发展水平的优化路径在于优化工业结构、提升发展效益、改善环境效率、增强创新能力。     

资源型城市产业结构分析——以甘肃省白银市为例

基于产业结构理论,分析了白银市产业结构的演变历史与现状,以期为白银市产业结构优化提供对策依据。白银市产业结构的特征为:产业结构演变过程的非自然历史性;产业结构总体落后,发展不平衡;城市经济发展的主要动力来源于第二、三产业;城市化水平与工业化水平发展不协调;三次产业结构整体转换能力弱;产业结构单一化;产业结构与就业结构高度错位;农业是以种植业为主的传统农业结构;工业结构主要是以能源、原材料为主的重工业;服务业发展水平低,波动性大。     

淮河流域新型城镇化水平的空间差异及其影响因素分析

以淮河流域31个地级市为研究对象,从人口、经济、生活和环境四个方面构建了新型城镇化水平的综合评价指标体系,利用熵值法对其综合城镇化水平及其子系统水平进行评价.结果表明,淮河流域地区新型城镇化发展水平存在较强的空间依赖性,即一个地区城镇化水平的提高通过空间溢出促进周边地区的城镇化发展,地区产业结构的变化是决定其新型城镇化水平的主要因素,尤其是第三产业发展对其影响极大.     

济南市城镇化与城市土地利用效益耦合协调发展研究

以济南市为例,通过构建城镇化与土地利用效益综合评价指标体系,使用熵值法计算得出两者的综合指数,结合耦合度、协调度模型分析城镇化子系统和土地利用效益子系统的耦合交互机制。结果表明:2007—2016年间济南市城镇化综合指数和土地利用效益综合指数均呈上升趋势,个别年份两者的综合指数存在波动;城镇化子系统和土地利用效益子系统间的耦合度除2007年外始终处于颉颃阶段,协调度则始终处于严重失调阶段,但耦合度指数和协调度指数都在不断增加,说明两个子系统间的耦合度和协调度均向更好的方向发展。在未来发展中,济南市要积极提升土地利用效益,推进城市土地利用合理布局与结构优化,从而促进城市健康发展。     

“一带一路”沿线省区科技创新与旅游经济协调发展及影响因素研究

以我国“一带一路”沿线18个省区为考察区域,运用熵值法、耦合协调分析和面板数据模型,构建科技创新与旅游经济协调发展评价体系,对两大子系统发展、综合协调发展及其影响因素进行研究。结果表明:①我国“一带一路”沿线省区科技创新与旅游经济子系统呈相对稳定或显著上升发展特征,长三角和珠三角等沿海地区发展等级较高,而西北内陆省区较低。②2006—2018年,多数省区科技创新与旅游经济综合评价水平呈稳定上升态势,且优势型省区均集中在东南沿海地区。③科技创新与旅游经济系统间联系不断增强并向良性协调方向发展,提升科技创新能力是多数省区实现两系统协调发展的重点。④旅游人力资本、创新支撑环境和科技创新产出是两大系统协调发展的重要影响因素。     

湖南省土地资源生态安全评价

基于P—S—R（压力一状态一响应）模型从土地资源生态安全的压力子系统、状态子系统、响应子系统三方面构建了湖南省土地生态安全评价指标体系,结合各评价指标的安全指数对2000--2008年湖南省土地资源生态安全状况进行了评价,分析了影响湖南省土地资源生态安全的限制因素。结果表明：①2000-2008年湖南省综合生态安全状况不容乐观,其生态安全等级多年来一直处于“临界安全”。②人口密度大、人均GDP低和不合理的化肥农药施用是湖南省土地资源压力子系统的主要限制因素,耕地面积少和农田水利设施差是状态子系统的主要限制因素,工业固体废弃物综合利用率偏低和教育卫生事业发展滞后是响应子系统的主要限制因素,据此提出了相应的对策建议。     

城市旅游竞争力的实证研究--以广东省为例

城市旅游竞争力研究是目前国内外城市旅游研究的热点.作为我国城市旅游发展较早的地区,广东省旅游业发展的整体水平较高,但各个城市之间的发展水平极度不平衡.在统计资料的基础上,建立了城市旅游竞争力指标体系,并用主成分分析法和系统聚类法对广东省21个地级市的旅游竞争力进行了综合对比分析,认为旅游规模与组织能力是影响广东旅游业发展的重要因素;同时,把广东省21个地级市按照旅游竞争力的大小分为综合型、客源地型、目的地型和待开发型4大类型,提出了广东省要提高城市旅游竞争力、实现城市旅游可持续发展必须制订合理的发展目标、加大旅游投入力度、完善旅游交通网络、加强旅游行业管理.     

铜陵市城市综合竞争力比较评价及战略对策

随着世界城市体系的形成、扩大和调整，城市在区域经济中的地位变得更加重要，城市成为国家和区域间竞争的主要载体和平台。重视和提升城市竞争力是有效推进城市化和提高区域经济水平的关键所在，它已成为各个国家和区域关注与研究的重点。运用定量方法，比较分析了铜陵市综合经济实力、产业、企业、开放、科技、基础设施、人力资源和城市环境等8个方面区域竞争力水平。结果表明，铜陵市具有良好的区位竞争优势，在皖江城镇带中具有较高的区域竞争力水平，产业优势是其核心竞争力的重要方面；但总量规模小、生态环境污染严重是阻碍其城市综合竞争力进一步提升的重要因素。     

“十五”科技发展六大具体目标

一是产业技术水平和国际竞争力大幅度提升,使我国农业和工业、服务业主要领域的技术水平达到发达国家２０世纪９０年代中期水平;Ｈ是基础研究和战略高技术研究有所突破;三是为人口、资源、环境协调发展提供科技支撑;四是全社会科技投人明显增长,全社会研究与发展经费占国内生产总值的比例提高到１．５％以上;五是科技人才不断满足发展需求;六是科技基础设施逐步完善。“十五”科技发展六大具体目标     

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.