淮河流域(河南段)水质时空变化特征及其与土地利用类型的关系

水质的定量评估有利于地方政府制定和实施水污染防治政策.为研究近期淮河流域行政区划尺度上水质的时空变化特征及其受土地利用类型的影响,以淮河流域（河南段）为研究区,根据2009-2017年31个水质站点的水质周测浓度,结合土地利用遥感监测数据,利用季节性Mann-Kendall趋势检验法及Spearman相关分析法,对ρ（COD_Cr）、ρ（NH₄+-N）和ρ（TP）的时空变化特征及其与土地利用类型的相关性进行分析.结果表明:①在时间上,ρ（COD_Cr）、ρ（NH₄+-N）和ρ（TP）在大部分地区呈下降趋势,但各水质指标依然较高,ρ（COD_Cr）和ρ（TP）在丰水期略高于枯水期,ρ（NH₄+-N）在枯水期高于丰水期.②在空间上,水污染比较严重的有沱河、浍河、惠济河、涡河、贾鲁河、清潩河、颍河中游、黑茨河、汾泉河和洪汝河,大部分站点为GB 3838-2002《地表水环境质量标准》Ⅳ类或Ⅴ类水质,部分站点甚至属于GB 3838-2002劣Ⅴ类水质;而颍河上游、北汝河、沙河、淮河干流及史灌河的水质较好,基本属于GB 3838-2002Ⅰ类或Ⅱ类水质.③土地利用类型与水质之间的相关性表现为ρ（COD_Cr）、ρ（NH₄+-N）、ρ（TP）与旱地和城镇面积占比均呈正相关,与林地、草地和荒地面积占比均呈负相关,与水域面积占比也呈负相关但不显著.研究显示,淮河流域（河南段）水质有所改善,但部分地区水污染问题仍然比较严重,旱地与城镇用地是造成研究区水污染的主要原因,林地、草地、荒地和水域能够缓解水污染.      

Lysosomal enlargement and lysosomal membrane destabilisation in mussel digestive cells measured by an integrative index

Lysosomal responses (enlargement and membrane destabilisation) in mussel digestive cells are well-known environmental stress biomarkers in pollution effects monitoring in marine ecosystems. Presently, in laboratory and field studies, both responses were measured separately (in terms of lysosomal volume density - Vv - and labilisation period -LP) and combined (lysosomal response index - LRI) in order to contribute to their understanding and to develop an index useful for decisions makers. LRI integrates Vv and LP, which are not necessarily dependent lysosomal responses. It is unbiased and more sensitive than Vv and LP alone and diminishes background due to confounding factors. LRI provides a simple numerical index (consensus reference = 0; critical threshold = 1) directly related to the pollution impact degree. Moreover, LRI can be represented in a way that allows the interpretation of lysosomal responses, which is useful for environmental scientists.     

2016~2017年长荡湖流域河湖系统营养盐时空分布机制分析

以江苏省常州市长荡湖流域河湖系统为研究对象,基于野外监测与室内分析,探讨了水体氮、磷等营养盐的时空分布特征及其影响因素.结果表明,2016~2017年长荡湖流域河湖系统氮、磷污染突出,河流TN、NO₃^--N、NH₄⁺-N、TP和Chla平均质量浓度和高锰酸盐指数分别为（3.70±0.76）mg ·L^-1、（1.81±0.42）mg ·L^-1、（1.03±0.61）mg ·L^-1、（0.38±0.31）mg ·L^-1、（25.74±37.00）μg ·L^-1和（6.35±0.81）mg ·L^-1.河流总氮污染季节差异明显,表现为冬、春季劣于夏、秋季,河流总磷污染表现为秋、冬季劣于春、夏季,空间差异表现为北 > 西北 > 南 > 东部,河流处于中~高度富营养化状态.湖区TN、NO₃^--N、NH₄⁺-N、TP和Chla平均质量浓度和高锰酸盐指数分别为（2.25±0.94）mg ·L^-1、（0.98±0.47）mg ·L^-1、（0.19±0.14）mg ·L^-1、（0.11±0.03）mg ·L^-1、（18.71±8.76）μg ·L^-1和（4.59±1.09）mg ·L^-1,氮、磷质量浓度均超过Ⅲ类水标准,在空间上表现为从西部向东、南部降低的趋势,湖区处于轻~中度富营养状态.丹金溧漕河、通济河与薛埠河等河流是长荡湖流域河湖水系的主要污染物输送通道,丹金溧漕河干流输送氮、磷年通量最大,约为通济河和薛埠河年通量总和的10~12倍.长荡湖流域河流氮、磷污染同时受到农业面源污染物流失与城镇污水排放的影响.土地利用方式转变和大气沉降是导致长荡湖流域河湖系统氮、磷污染加剧的重要驱动因素.     

Social and economic impacts of carbon sequestration and land use change on peasant households in rural China: a case study of Liping, Guizhou Province

Numerous innovative approaches to mitigate effects of excessive emission of greenhouse gases (GHGs) on global climate change are being proposed and formulated. Sequestering carbon to terrestrial ecosystems represents one of the important clean development mechanisms. Reforestation through converting various non-forest lands to forests is undoubtedly an important dimension of carbon sequestration. Using Liping County in Guizhou Province as a case region, this study examines the perceived change in social and economic livelihoods of peasants and the factors responsible for the variations in the changes. The results of the study reveal that socio-economic changes associated with the government-financed project are multifaceted and profound. Because of the financial subsidies provided by the central government, this environmental action in many aspects can be regarded as a poverty reduction measure in the underdeveloped area where rural poverty is widespread. A majority of peasant households have benefited from project participation. The land conversion project with continued financial support also contributes to the social transformations of traditional rural society in remote areas to a more mobile, less subsistence agriculture-based, and open society.     

Comparison of vegetation conditions along two backcountry trails in Mount Robson Provincial Park, British Columbia (Canada)

Vegetation conditions, i.e., plant cover, species richness, and the presence of exotic species, are compared along a high-use trail (Berg Lake Trail--BLT) and a low use trail (Mt. Fitzwilliam Trail--FWT) in Canada's Mt. Robson Provincial Park. We established 71 paired quadrats (1 m x 1 m), and assessed the amount of vegetation cover and species richness by four main lifeforms, i.e., woody species, herbaceous species, ferns, and moss, lichen and fungi. The following hypotheses were tested: (1) differences exist between control and trailside quadrats in vegetation cover, species richness and floristic diversity, and (2) differences exist between the high and low-use trails in the above-mentioned three parameters. Results show that for the majority of variables the differences between the control and trailside quadrats are statistically not significant. Variables showing significant differences are relative vegetation cover (for BLT only), exposed soil (BLT and FWT), herbaceous cover (FWT), moss, lichen and fungi cover (BLT), overall species richness (BLT), and herbaceous species richness (BLT). Ruderal and exotic species are present but only on trailside quadrats of the high-use trail. Results indicate that the Park administration's strategy to disperse use in the Mt. Robson Provincial Park should be examined critically, and some guidelines for acceptability of changes should be developed.     

Ecological monitoring of urban groups of stray dogs: An example of the city of petrozavodsk

The results of the census of stray dogs and data on their territorial distribution in the city of Petrozavodsk are reported. The population density of these animals has been found to vary within the urban area, depending mainly on the availability of secluded areas to live in and on population control by municipal services.     

全球气候变化框架公约执行中的协商性谈判探讨

1992年联合国通过了《联合国气候变化框架公约》。在同年6月地球首脑会议上,155个国家签署了该公约。随着公约内容的具体化,围绕缔约国之间控制温室气体排放这个主议题,将展开政治、经济、法律、环境诸方面的分工协作以控制全球气候的变化。因此有必要在多边谈判和实施公约的工作中,讨论协商性谈判问题。本文探讨了该问题并就协商性谈判提出一些原则性建议。     

基于iLME+Geoi-RF模型的四川省PM2.5浓度估算

高分辨率PM2.5空间分布数据对动态监测和控制PM2.5污染具有重要意义.选取Himawari-8气溶胶光学厚度(AOD)、ERA5气象再分析资料、DEM、土地利用数据、夜光遥感数据、增强型植被指数和人口数据等作为估算变量,使用改进的重采样法进行数据匹配,并提出改进的线性混合模型(iLME)结合地理智能随机森林(Geoi-RF)构建组合模型估算PM2.5浓度.结果表明:①在选取的估算变量中,气溶胶光学厚度、气压、温度、相对湿度和边界层高度是影响2016年四川省PM2.5浓度的重要因素,其相关系数分别为0.65、0.58、0.55、0.54和0.35.②iLME+Geoi-RF模型精度相较其他模型有较大提升,模型拟合Rl2、RMSR 和 MAE 分别为0.98、3.25 μg·m-3和 1.98 μg·m-3,交叉验证 R2、RMSR 和 MAE 分别为0.89、7.95 μg·m-3和4.81μg·m-3.该模型可获取更高精度的四川省PM2.5时空分布特征,为区域空气质量评估、人体暴露风险评价和环境污染治理提供更加合理地科学参考.③2016年四川省PM2.5浓度存在显著的季节性差异,各季节PM2.5浓度大小关系为:冬季＞秋季＞春季＞夏季.2016年四川省月均PM2.5浓度总体上呈先降后升的"V"型趋势,最小值在6月,最大值在12月,8月和11月有微小起伏.在空间分布上四川省PM2.5浓度总体上呈东高西低和局部污染程度较高的特点,高值区主要分布在城市快速发展和人口密集的东部地区,低值区主要分布在经济发展落后和人口稀疏的西部地区.④虽然不同模型估算出的PM2.5浓度整体分布基本一致,但iLME+Geoi-RF模型能更准确有效地估算本研究区污染的空间分布.     

丹东市空气SO_2污染特征分析

通过空气质量自动监测、污染源监测及SO2网格落地浓度,分析丹东市空气SO2污染的时空变化规律和污染特征。     

Forest Cover Change,Physiography, Local Economy,and Institutions in a Mountain Watershed in Nepal

This study assessed changes in forest cover in a mountain watershed in central Nepal between 1976 and 2000 by comparing classified satellite images coupled by GIS analyses, and examined the association of forest change with major physiographic, economic, and local forest governance parameters. The results showed an increase in forested area (forest plus shrublands) by 7.6% during 1976–2000. Forest dynamism (changes including improvement, deterioration, gain, and loss) was highest in low-elevation, south-facing and less-steep slopes that were closer to roads. Proportionately the highest net improvement and gain to forested area also took place in those locations. Forest degradation occurred at twice the rate of improvement in high elevation areas (> 2300 m). Forests located in urban and semiurban areas (i.e., a market-oriented economy) experienced a proportionately higher amount of net improvement and gain than forests in rural areas (i.e., a subsistence economy). Among the three governance arrangements, proportionately the highest net improvement and gain took place in semigovernment forests (forested area legally under the forest department but with de facto control and claim of ownership by local communities and/or municipality) followed by formalized community forests (including leasehold). Government forests, which were mostly found in the southern high mountains and had virtually open access, remained relatively stable during the study period. Over 50% of the watershed forests have not come under community-based management despite favorable policy and more than two decades of government intervention with continuous donor support. The findings indicate that the present one size fits all approach of community forest handover policy in Nepal needs rethinking to accommodate biophysical and socioeconomic variations across the country.