北美国家的湿地恢复及对中国太湖恢复的启示

以美国旧金山海湾带和加拿大安大略省沼泽湿地生态恢复为例,探讨了其成功经验,并指出了我国太湖恢复建设主要存在五个方面问题：理论技术体系相对滞后;恢复工程实施系统性缺乏;投融资方式单一化;恢复管理体系不完善;公众参与力度薄弱。据此提出相关建议,力求探索完善我国太湖生态恢复的有效路径。     

Exploring the effects of multiple management objectives and exotic species on great lakes food webs and contaminant dynamics

A simulation model was developed to describe linkages among fish food web, nutrient cycling, and contaminant processes in the southern basin of Lake Michigan. The model was used to examine possible effects of management actions and an exotic zooplankter (Bythotrephes) on Lake Michigan food web and contaminant dynamics. The model predicts that contaminant concentrations in salmonines will decrease by nearly 20% ifBythotrephes successfully establishes itself in the lake. The model suggests that this decrease will result from lowered transfer efficiencies within the food web and increased flux of contaminants to the hypolimnion. The model also indicates that phosphorus management will have little effect on contaminant concentrations in salmonines. The modeling exercise helped identify weaknesses in the data base (e.g., incomplete information on contaminant loadings and on the biomass, production, and ecological efficiencies of dominant organisms) that should be corrected in order to make reliable management decisions.     

水库淹没区耕地生态服务功能价值估算研究——以黄金坪水电站为例

以黄金坪水电站为例,采用碳税法、造林成本法以及工业氧价格替代法计算气体调节功能价值,并采用其它多种方法计算水土保持价值,以估算水库淹没区耕地生态服务功能价值。通过研究,使水库淹没区耕地总价值构成及量化趋于合理,为进一步完善淹没区耕地补偿构成和补偿标准提供参考。     

大兴安岭火烧迹地土壤动物的群落多样行

以大兴安岭地区不同年份火烧迹地土壤动物为研究对象,对火烧后不同恢复时间土壤动物群落多样性及相关指数的变化进行分析.结果表明,大型土壤动物的个体数、DIC指数、丰富度指数及优势度指数变化趋势均表现为火烧恢复初期迅速增加,然后缓慢增加并逐渐接近对比样地值;如果不考虑8 a迹地数据极大值的影响,中小型土壤动物的个体数、DIC指数、丰富度指数及优势度指数也大致呈现火烧恢复初期迅速增加,然后缓慢增长的趋势;在垂直方向上,大型土壤动物DIC指数、个体数及丰富度指数在0～5 cm最大,向上、向下减少,而中小型土壤动物的各项指数都是凋落物层最大,向下迅速减小;相关分析表明,大型和中小型土壤动物的个体数和丰富度指数与DIC指数都具有极高的相关性;群落相似性分析显示,各火烧迹地间土壤动物群落具有较高的相似性.图1表3参26     

Microplastic contamination in Great Lakes fish

Freshwater ecosystems, generally adjacent to human population and more contaminated relative to adjacent marine ecosystems, are vulnerable to microplastic contamination. We sampled 7 species of fish from Lake Ontario and Lake Superior and assessed their gastrointestinal (GI) tracts to quantify ingested microplastics and other anthropogenic particles. A subset of the microparticles were chemically analyzed to confirm polymer types and anthropogenic origins. We documented the highest concentration of microplastics and other anthropogenic microparticles ever reported in bony fish. We found 12,442 anthropogenic microparticles across 212 fish (8 species) from nearshore Lake Ontario, 943 across 50 fish (1 species) from Humber River, and 3094 across 119 fish (7 species) from Lake Superior. Fish from Lake Ontario had the greatest mean abundance of anthropogenic microparticles in their GI tracts (59 particles/fish [SD 104]), with up to 915 microparticles in a single fish. Fish from Lake Superior contained a mean [SD] of 26 [74] particles/fish, and fish from Humber River contained 19 [14] particles/fish. Most particles were microfibers. Overall, ≥90% of particles were anthropogenic, of which 35-59% were microplastics. Polyethylene (24%), polyethylene terephthalate (20%), and polypropylene (18%) were the most common microplastics. Ingestion of anthropogenic particles was significantly different among species within Lake Ontario (p < 0.05), and the abundance of anthropogenic particles increased as fish length increased in Lake Ontario (ρ = 0.62). Although we cannot extrapolate the concentration of microplastics in the water and sediments of these fish, the relatively high abundance of microplastics in the GI tracts of fish suggests environmental exposure may be above threshold concentrations for risk.