Eliciting preferences for wetland services: a way to manage conflicting land uses

A choice experiment was used to analyse the preferences of residents neighbouring the Erstein polder (Alsace, France) for the different services that it provides. The heterogeneous nature of these preferences was shown through the use of a latent class model. Whilst the population as a whole values the improvement in water quality and the contribution, even partial, to flood protection, preferences differ when it comes to biodiversity and public access to the site. This study shows the potential conflicts between the different uses of the Erstein polder. These conflicts represent different communication themes for the site managers.     

生物法/人工湿地工艺处理采油废水及其生态毒性削减研究

采用2种生物法/人工湿地工艺(水解酸化/好氧/人工湿地工艺和水解酸化/人工湿地(进水区强化曝气)工艺)处理胜利油田某联合处理站经隔油、混凝处理的采油废水,并运用发光细菌技术研究采油废水在处理过程中的生态毒性削减规律.研究结果表明,在水解酸化段水力停留时间(HRT)为20 h,好氧段HRT为10 h,人工湿地HRT为2 d的工况下,水解酸化/好氧/人工湿地工艺与水解酸化/人工湿地(进水区强化曝气)工艺的出水水质均能满足COD≤80 mg/L、NH_4~+-N≤15 mg/L的处理要求.发光细菌法试验结果表明,经隔油、混凝处理后的采油废水属高毒性废水,再经水解酸化/人工湿地(进水区强化曝气)工艺处理后生态毒性大幅削减,出水生态毒性降至低毒.     

天然和巯基改性沸石吸附水溶液中重金属Hg^2＋的特征研究

为了提高沸石对汞的吸附性,利用半胱胺盐酸盐对天然斜发沸石进行改性,制得巯基改性沸石。研究了吸附剂用量、pH值、温度、Hg^2＋浓度和吸附时间对沸石和巯基改性沸石吸附Hg^2＋的影响,并进一步研究了吸附机理。结果表明,巯基改性沸石吸附Hg^2＋受pH值、温度的影响较小,吸附机制主要是沸石表面的硫与Hg^2＋的化学反应。而天然沸石对Hg^2＋的吸附主要是离子交换作用,受温度、pH值等的影响较大,随温度的升高吸附量下降。整个吸附过程以较快的速度进行。天然沸石在吸附时间为1h、巯基改性沸石在0．5h时基本达到吸附平衡。吸附条件试验和Langmuir等温吸附模型都表明,巯基改性沸石对Hg^2＋的吸附能力得到了很大的提高,吸附容量由8．06mg／g提高到19．88mg／g,提高了146．65％。     

High methane emissions from a littoral zone on the Qinghai-Tibetan Plateau

The littoral zones of lakes have been regarded as hotspots of methane (CH₄) fluxes through several studies. In the present study, we measured CH₄ fluxes in six kinds of littoral zones of Huahu Lake on the Qinghai-Tibetan Plateau in the peak growing season of 2006 and 2007. We found that CH₄ efflux (ranging from −0.1 to 90 mg CH₄ m⁻² h⁻¹) from the littoral zones of this lake was relatively high among those of boreal and temperate lakes. Our results also showed that emergent plant zones (Hippuris vulgaris and Glyceria maxima stands) recorded the highest CH₄ flux rate. The CH₄ flux in the floating mat zone of Carex muliensis was significantly lower than those of the emergent plant zones. CH₄ fluxes in the floating-leaved zone of Polygonum amphibium and bare lakeshore showed no significant difference and ranked last but one, only higher than that of the littoral meadow (Kobresia tibetica). Plant biomass and standing water depths were important factors to explain such spatial variations in CH₄ fluxes. No significant temporal variations in CH₄ fluxes were found due to the insignificant variations of physical factors in the peak growing season. These results may help in our understanding of the importance of the littoral zone of lakes, especially the emergent plant zone, as a hotspot of CH₄ emission.     

人工湿地中基质与植物对污染物去除效率的影响

针对太湖五里湖富营养化水体,采用中试规模的人工湿地现场实验开展了不同基质、不同植物的污染物去除效果研究。基质采用炉渣和沸石2种,在一个湿地池种植单一植物茭白,另一个湿地池种植鸢尾＋菖蒲混合植物,同时构建了无植物的对照组湿地。研究表明：（1）在运行初期,沸石和炉渣2种基质对TN、TP的去除率差异为12.5%和12.6%,吸附饱和后,2种基质对TN和TP的去除率差异缩小为3.2%和6.1%,从长期运行来看,炉渣和沸石2种基质在人工湿地中的去除效率差异将减小;（2）茭白单一植物湿地对污染物的去除率与鸢尾＋菖蒲混合植物湿地对污染物的去除率两者之间差异不大;（3）人工湿地种植植物后对TN、TP的去除率比无植物状态时分别高出13.6%和19.5%,植物在人工湿地中对污染物的去除发挥了重要作用;（4）在本试验条件下,茭白吸收所去除的氮数量为湿地氮总去除量的8.95%,茭白吸收去除磷的数量为湿地磷总去除量的20.16%,在人工湿地中,茭白吸收对磷的去除效率比对氮的去除效率高。     

A Comparison of Sampling Designs for Monitoring Recreational Trail Impacts in Rocky Mountain National Park

The dual goals of the Organic Act of 1916 and Wilderness Act of 1964 are to protect natural resources and provide quality visitor experiences. Park managers need metrics of trail conditions to protect park resources and quality of visitor experiences. A few methods of sampling design for trails have been developed. Here, we describe a relatively new method, spatially balanced sampling, and compare it to systematic sampling. We evaluated the efficiency of sampling designs to measure recreation-related impacts in Rocky Mountain National Park. This study addressed two objectives: first, it compared estimates of trail conditions from data collected from systematic versus spatially balanced sampling data; second, it examined the relationship between sampling precision and sampling efficiency. No statistically significant differences in trail condition were found between the 100-m interval and the spatially balanced datasets. The spatially balanced probability-based dataset was found to be a good estimate of trail conditions when analyses were conducted with fewer sample points. Moreover, spatially balanced probability-based sampling is flexible and allows additional sample points to be added to a sample.     

微生物对芦苇人工湿地除磷影响研究

以上海梦清园人工芦苇湿地为对象,在微生物制剂使用的同时研究了微生物对湿地除磷效果的影响。经过对近一年的数据分析表明,微生物的增加使总磷平均去除率达到20．9％,高于空白的18．3％。微生物的磷酸化作用使得出水磷更多以磷酸根形式表达,甚至使磷酸盐含量不降反升。底泥监测表明,微生物制剂的加入能有效的促进浮泥层中磷的转移,减缓浮泥层中磷的积累,10个月后试验组浮泥层的磷含量相对空白对照组可降低10％以上,菌剂对于减缓磷的积累,促进磷向基质转移有重要意义。     

洞庭湖区洪涝灾情评估与分析

运用三因子联立评估法,评定了洞庭湖区洪灾、涝灾和洪涝灾的灾度,进行了相应的分析;构建了洪涝灾情指数,并运用联环替代法对各灾情因素的影响进行了分析。分析得出：洞庭湖区洪涝灾度具有阶段性和准周期性等特征;洪水灾情因素是综合灾情变化的主导影响因素;各灾情因素影响方向不完全一致,其中起放大作用的因素反映出洪涝灾害的新特点;涝灾日趋严重,应加强涝灾治理。     

污水湿地处理工艺优化组合设计

污水湿地处理系统是利用土壤、作物、微生物自然净化功能的生态工程技术。主要有水面湿地和渗滤湿地两种类型,在天津城市污水土地处理与利用系统研究的基础上,将两种工艺的优点进行优化组合,并应用于大港油田等污水湿地处理工程,运行结果表明：将水面湿地和渗滤湿地工艺优化组合设计的示范工程,具有提高水力负荷、减少运行费用、节省工程投资、处理效果稳定等特点,有利于处理工程的长期稳定运行。     

洞庭湖湿地稻区化肥环境影响评估

研究采用时间序列分析法,预测洞庭湖区2010年2、020年人口将分别达到1 396.38×104人、1 492.31×104人,稻谷总需求量分别为5 002.17×103t,5 284.79×103t,化肥投入实物量将分别为1 466.91×103t,1 549.79×103t。在总结国内外化肥投入影响环境研究基础上建立了化肥环境影响评估模型,预计2010,2020年洞庭湖区区水稻生产因化肥带来环境成本将分别达到2.2×108元、2.32×108元,占稻谷销售效益的3.4%和3.13%,稻田生态系统和社会将难以承受,建议政府在化肥过量施用的地区征收化肥环境税。