促进江湖联系的闸口调度对策及影响区管理机制

我国传统的修堤建闸、抵御洪水的治河理念,阻断了江湖联系,造成湿地的生态萎缩。为改善湿地的生态环境,保护湿地的生物多样性,提出了新的多目标闸口调度机制,替代传统的、以防洪抗旱为目的的调度机制,力求促进江湖联系,增加湿地活力;为保障该机制的运行和实施,提出了闸口调度影响区的管理办法;并以涨渡湖为例进行了讨论。     

崇西湿地冬季潮滩鱼类种类组成及多样性分析

根据2006年冬季在崇西湿地进行的光滩和草滩插网渔获调查,首次对冬季长江口潮滩鱼类种类组成、多样性及相关环境因子作了分析。结果表明：冬季崇西湿地潮滩鱼类主要由淡水小型鱼类组成,共23种,隶属7科,20属。光滩和草滩插网的最大优势种皆为油,两种网具的渔获种类组成具一定的相似性。在一个潮周期内,3种多样性指数D、H′ 和J值波动范围较大,小汛潮时多样性指数比其它潮汛低。白天和晚上潮水的鱼类种类数无显著变化（P>0.5）,但在个体数和生物量上白天较晚上潮水高（P<0.5）。水温、潮汐大小对潮滩鱼类丰度影响较大,而与盐度相关较小。此外,天气状况也是影响潮滩鱼类的一个重要因子。总之,潮滩鱼类的种类组成和多样性受到各种环境因子的综合影响。     

Nitrogen cycle of a typical Suaeda salsa marsh ecosystem in the Yellow River estuary

The nitrogen (N) biological cycle of the Suaeda salsa marsh ecosystem in the Yellow River estuary was studied during 2008 to 2009. Results showed that soil N had significant seasonal fluctuations and vertical distribution. The N/P ratio (15.73±1.77) of S. salsa was less than 16, indicating that plant growth was limited by both N and P. The N absorption coefficient of S. salsa was very low (0.007), while the N utilization and cycle coefficients were high (0.824 and 0.331, respectively). The N turnover among compartments of S. salsa marsh showed that N uptake from aboveground parts and roots were 2.539 and 0.622 g/m2, respectively. The N translocation from aboveground parts to roots and from roots to soil were 2.042 and 0.076 g/m2, respectively. The N translocation from aboveground living bodies to litter was 0.497 g/m2, the annual N return from litter to soil was far less than 0.368 g/m2, and the net N mineralization in topsoil during the growing season was 0.033 g/m2. N was an important limiting factor in S. salsa marsh, and the ecosystem was classified as unstable and vulnerable. S. salsa was seemingly well adapted to the low-nutrient status and vulnerable habitat, and the nutrient enrichment due to N import from the Yellow River estuary would be a potential threat to the S. salsa marsh. Excessive nutrient loading might favor invasive species and induce severe long-term degradation of the ecosystem if human intervention measures were not taken. The N quantitative relationships determined in our study might provide a scientific basis for the establishment of effective measures.     

简讯

环保部：今年1～8月全国发生11起重金属污染事件 环保部部长周生贤近日表示,损害群众健康的环境问题仍然比较突出。近年来,重金属污染事件呈高发态势。今年1～8月,全国发生11起重金属污染事件,其中9起为血铅事件。在全国排查的4．46万家化学品企业中,72％分布在长江、黄河、珠江、太湖等重点流域沿岸,距离饮用水水源保护区、重要生态功能区等环境敏感区不足1公里的占12．2％。     

兰州银滩湿地5种植物对重金属吸附能力的分析

利用原子吸收分光光度法测定兰州银滩湿地5种植物及其生长土壤(表层)中Cu、Pb、Zn的含量,结果表明,采样区域表层土壤存在轻度Cu、Zn、Pb污染,其中Cu、Pb的来源或污染途径可能相同,且Cu、Zn、Pb的生物可利用性较低,TCLP生态风险评价显示均小于国际标准值;采样区域表层土壤Cu、Zn、Pb总量与TCLP提取量...     

《环境科学与技术》总目次

<正>~~     

人工湿地堵塞机理与应对措施研究

综述了现今国内外人工湿地污水处理系统堵塞的成因,分析了目前比较通用的预防手段、恢复措施和研究现状,并提出了今后人工湿地防淤堵技术的研究发展方向.     

基于多期遥感数据对岱海湿地的景观格局分析

文章提取了3期遥感数据的湿地类型,通过对景观格局的动态变化分析,说明了人为干扰和气候因素对岱海湿地的影响,为湿地管理提供了依据。     

不同基质的人工湿地去除猪场沼液中磷的性能

以猪场沼液为研究对象,通过静态吸附试验研究沸石、硅藻土、煤渣、铁粉、石英砂5种基质对磷的等温吸附特征,并采用一级和二级动力学模型分析吸附动力学过程。根据试验结果,构建了4种人工湿地单元研究人工湿地对猪场沼液处理效果及对高浓度沼液的抗冲击能力。结果表明,5种基质对总磷的吸附更符合非线性Langmuir方程。准二级动力学方程更能描述各种基质对总磷的动力学吸附过程。沸石对磷的最大饱和吸附量1.868 mg/g,对磷去除率最高,可达到96.01%。沸石-垂直流人工湿地在构建的4种人工湿地单元中具有最强抗冲击能力。     

Nitrogen mass balance in a constructed wetland treating piggery wastewater effluent

The nitrogen changes and the nitrogen mass balance in a free water surface flow constructed wetland （CW） using the four-year monitoring data from 2008 to 2012 were estimated. The CW was composed of six cells in series that include the first settling basin （Cell 1）, aeration pond （Cell 2）, deep marsh （Cell 3）, shallow marsh （Cell 4）, deep marsh （Cell 5） and final settling basin （Cell 6）. Analysis revealed that the NH4＋-N concentration decreased because of ammonification which was then followed by nitrification. The NO4＋-N and NO4＋-N were also further reduced by means of microbial activities and plant uptake during photosynthesis. The average nitrogen concentration at the influent was 37,819 kg/year and approximately 45% of that amount exited the CW in the effluent. The denitrification amounted to 34% of the net nitrogen input, whereas the accretion of sediment was only 7%. The biomass uptake of plants was able to retain only 1% of total nitrogen load. In order to improve the nutrient removal by plant uptake, plant coverage in four cells （i.e., Cells 1, 3, 4 and 5） could be increased.