长江口邻近海域表层沉积物中的细菌藿多醇及对低氧区的响应判别

作为新型细菌生物标志物的细菌藿多醇（bacteriohopanepolyols,BHPs）在有机质来源追踪和环境变化响应等方面有明确的指示作用.本文应用高效液相色谱串联大气压化学电离源质谱法（HPLC-APCI-MS）分析,在解析长江口邻近海域表层沉积物中BHPs的组成、分布和来源特征基础上,探讨了BHPs对长江口邻近海域季节性低氧的指示作用.结果表明,长江口邻近海域表层沉积物中共检测出12种BHPs,其含量范围（以TOC计）为3.79~269 μg·g^-1.BHPs以细菌藿四醇（bacteriohopanetetrol,BHT）、2-甲基BHT、氨基BHPs和腺苷藿烷及同系物为主要组分,分别占总量的40%、22%、12%和4%.各组分含量及相应指标呈现出明显的空间变化趋势,其中,主要来源于海洋自生来源的BHT呈现明显的"离岸增加"趋势;主要为陆源贡献的腺苷藿烷等土壤标志物BHPs呈现明显的"离岸降低"特征.Rsoil指数呈现出与腺苷藿烷等土壤标志物BHPs相似的空间分布格局,其陆源有机质贡献从近岸的61.5%下降至外海的1.66%,表明长江口邻近海域近岸有机质主要为陆源输入,而外海主要为海源贡献.细菌藿四醇同分异构体BHT-Ⅱ来源于厌氧氨氧化细菌,其相对含量的高值区与长江口低氧区分布相一致,且与底层水溶解氧（DO）含量呈显著负相关,表明低氧环境有利于BHT-Ⅱ的生成,BHT-Ⅱ可用于指示海洋低氧区环境特征.     

Perspectives on area-based conservation and its meaning for future biodiversity policy

During 2021, Parties to the Convention on Biological Diversity (CBD) are expected to meet in Kunming, China, to agree on a new global biodiversity framework aimed at halting and reversing biodiversity loss, encouraging the sustainable use of biodiversity, and ensuring the equitable sharing of its benefits. As the post-2020 global biodiversity framework evolves, parties to the convention are being exposed to a range of perspectives on the conservation and sustainable use of biodiversity, relating to the future framework as a whole or to aspects of it. Area-based conservation measures are one such aspect, and there are diverse perspectives on how new targets might be framed in relation to these measures. These perspectives represent different outlooks on the relationship between human and nonhuman life on Earth. However, in most cases there is a lack of clarity on how they would be implemented in practice, the implications this would have for biodiversity and human well-being, and how they would contribute to achieving the 2050 Vision for Biodiversity of “living in harmony with nature.” We sought to clarify these issues by summarizing some of these perspectives in relation to the future of area-based biodiversity conservation. We identified these perspectives through a review of the literature and expert consultation workshops and compiled them into 4 main groups: Aichi+, ambitious area-based conservation perspectives, new conservation, and whole-earth conservation. We found that although the perspectives Aichi+ and whole earth are in some cases at odds with one another, they also have commonalities, and all perspectives have elements that can contribute to developing and implementing the post-2020 global biodiversity framework and achieving the longer term CBD 2050 Vision.     

基于未确知聚类法的巷道围岩稳定性预测

针对影响巷道围岩稳定性的因素多且具有不确定性和隐蔽性的特点,选取实测RQD值、单轴抗压强度、隙壁状态3个主要影响因素作为判别指标,利用未确知测度理论,建立巷道围岩稳定性预测模型。利用25组巷道围岩资料作为模型构建样本,以样本均值为聚类中心,采用信息熵理论确定各判别指标的权重,从而计算样本的多指标综合测度;根据最小未确知测度距离原理判断样本所属类别,进而对巷道围岩稳定性进行预测,且用逐一回代的方法检验预测模型的合理性。刊用所建立的巷道围岩稳定性预测模型对大冶铁矿5组待判别样本进行应用预测,预测结果符合工程勘察实际,表明基于未确知聚类法的巷道围岩稳定性预测方法具有较好的实用性和有效性。     

城市产业集中区环境性能评估体系的构建——基于北京市丰台区案例的探讨

城市产业集中区在推动城市产业发展和人口就业中发挥着重要作用,但其在发展过程中,对周边人口和环境带来的负面影响也越来越突出。鉴于现有研究对城市内部空间的环境效率研究不足,论文从环境性能的概念入手,结合产业集中区环境的复杂性、综合性特征,提出了包括社会经济贡献、环境负荷与环境风险3个维度的环境性能评估指标体系,并对污染源识别、空间单元选择等科学问题进行了探索。以北京市丰台区污染源普查数据、注册企业数据及风险源数据为数据基础,采取空间分析方法,定量评价其环境性能空间差异性。主要研究结果包括：提出了选取城市产业集中区环境性能评估空间单元的原则,并将丰台区划分为1 379个500 m×500 m格网单元,论证了环境性能评估的空间尺度效应,表明在更加精细的格网尺度上有利于探查局部空间分异格局;基于北京市丰台区案例,发现环境负荷高的地区主要集中在太平桥、方庄、西罗园、马家堡等东北部街道;环境性能低值区具有明显的中心城区指向、沿快速环路分布和批发市场指向等特征;根据评估结果建议从产业布局、定点管理、生态空间设置以及人口调控等方面为实施精细化的环境空间管控提供依据。     

黄土丘陵沟壑区农村特色生态经济模式探讨——以陕西绥德县为例

黄土丘陵沟壑区是我国北方生态脆弱、产业单一、广种薄收、乡村贫困的特殊问题区域。“越穷越垦、越垦越穷”的土地利用方式成为统筹人与自然和谐发展的关键“瓶颈”。论文运用农业地理学和生态经济学原理,以绥德县为典型案例区,进行了农村经济社会发展主要的限制因素剖析。认为该区土地资源利用必须正确处理宏观与微观效益的关系,加强水土保持、生态建设与脱贫解困目标的有机结合。依据研究区地形地貌特点与水土流失规律,重视旱作农业与节水灌溉技术、示范推广造林实用技术、水保型生态农业技术的创新与应用,大力发展柠条防护林产业化、水保型立体农业、生态资源开发增效等典型农村特色生态经济模式。     

中国西部贫困地区可持续发展研究

本文探讨了贫困与可持续发展的相互关系。在系统阐释中国西部贫困地区可持续发展面临的现实问题、困难和障碍的基础上,着重围绕西部贫困地区可持续发展的基本内容和实施途径进行了综合性的分析和研究。     

Goods in the Anthroposphere as a Metal Emission Source A Case Study of Stockholm,Sweden

The aim of this study was to quantify the diffuse emissionsduring use of metal containing goods in the capital of Sweden,Stockholm. The following metals were studied: Cadmium (Cd), Chromium (Cr), Copper (Cu), Lead (Pb), Mercury (Hg), Nickel (Ni) and Zinc (Zn).A major part of the metals are found in a protected environmentwhere degrading processes like corrosion are most limited. However, during the lifetime of some goods the metal release to the environment is significant. The quantitatively most dominant emissions were found for Cu and Zn. The tap water system and roofs/fronts (Cu) represent goods with large exposedareas but with relatively small release rates per unit. In contrast, brake linings, aerial lines and electrical grounding (Cu) and tyres, brake linings and chemicals (Zn) are allgoods with high release rates but mostly limited exposed stocks.High yearly emissions are also found for Pb, ammunition andsinkers dominate the calculated emissions totally. For Cr and Ni, stainless steel represent the major part of the stocks, butcorrosion was estimated to give only a minor contribution to the emissions. Potential emission sources, i.e. stabilisers,pigments and plated goods dominate the exposed Cd stock. Theseemissions were not quantified due to lack of data. Hg is currently phased out, but one major source of emission, i.e. the use of amalgam, will be continuously significant for several decades. The importance of the traffic sector is obvious. The emissionsfrom brake linings (Cu, Zn and Pb), tyres (Zn, Pb, Cr and Ni)and asphalt wear (Cu, Zn, Cr, Ni and Pb) are all of large importance for the total emission from respectively metal.     

Effects of Local Land Use on Physical Habitat, Benthic Macroinvertebrates, and Fish in the Whitewater River, Minnesota, USA

Best management practices (BMPs) have been developed to address soil loss and the resulting sedimentation of streams, but information is lacking regarding their benefits to stream biota. We compared instream physical habitat and invertebrate and fish assemblages from farms with BMP to those from farms with conventional agricultural practices within the Whitewater River watershed of southeastern Minnesota, USA, in 1996 and 1997. Invertebrate assemblages were assessed using the US EPA's rapid bioassessment protocol (RBP), and fish assemblages were assessed with two indices of biotic integrity (IBIs). Sites were classified by upland land use (BMP or conventional practices) and riparian management (grass, grazed, or wooded buffer). Physical habitat characteristics differed across buffer types, but not upland land use, using an analysis of covariance, with buffer width and stream as covariates. Percent fines and embeddedness were negatively correlated with buffer width. Stream sites along grass buffers generally had significantly lower percent fines, embeddedness, and exposed streambank soil, but higher percent cover and overhanging vegetation when compared with sites that had grazed or wooded buffers. RBP and IBI scores were not significantly different across upland land use or riparian buffer type but did show several correlations with instream physical habitat variables. RBP and IBI scores were both negatively correlated with percent fines and embeddedness and positively correlated with width-to-depth ratio. The lack of difference in RBP or IBI scores across buffer types suggests that biotic indicators may not respond to local changes, that other factors not measured may be important, or that greater improvements in watershed condition are necessary for changes in biota to be apparent. Grass buffers may be a viable alternative for riparian management, especially if sedimentation and streambank stability are primary concerns.     

城镇生活污水治理规划研究——以双阳区奢岭镇为例

实现农村生活污水有效治理在推进生态文明建设和农民生活方式现代化中具有标志性意义.通过对区域现状数据调研及分析,划分区域污水汇水分区及选择污水收集方式,合理确定用水指标和污水排放系数,预测生活污水量,布局生活污水处理设施建设.其结果表明:具备条件排入奢岭镇污水处理厂的镇区外村屯的污水,排入奢岭镇区污水处理厂.不具备条件的...     

盘锦近岸海域无机氮污染因子削减与预测

通过盘锦海域的海水质量和水文分析,建立盘锦海域潮流场模型。在不同输入条件下,利用潮流场模型对近岸海域的无机氮污染物含量变化响应进行模拟,得出3条河流(辽河、大辽河和大凌河)无机氮削减值,在此条件下可实现近岸海域无机氮达标要求。