上海池塘养殖环境成本——基于双边界二分式CVM法的实证研究

池塘养殖具有食品供给、空气质量调节、文化服务等多重功能,但在其生产过程中也会产生环境成本。正确认识池塘养殖的正、负生态服务价值,对于避免养殖生产过程中存在的盲目和短视、保持水产养殖业本身的可持续发展、促进水产养殖经济与环境的和谐发展具有重要的现实意义。依据双边界二分式CVM法,通过随机抽样调查法获得当地居民对于环境污染时的受偿意愿(WTA)水平,利用STATA10.0软件定量核算了2010年上海环淀山湖地区的池塘养殖环境成本为1982.26万元/a,约合5105元.a-.1hm-2)。研究表明,居民家庭收入、受教育程度、年龄等社会经济因素对居民的环境污染受偿意愿具有显著性的影响,但其具体的影响力大小和方向还有待进一步的探讨。研究同时表明,双边界二分式CVM法具有较强的稳定性,政府应综合考虑各种因素,制定并执行针对性、公平性的生态补偿政策。     

Mariculture development in Kenya: alternatives to siting ponds in the mangrove ecosystem

Pond culture of brackishwater prawns and shrimps has recently generated much interest in Kenya. The mangrove areas are the target zones for the construction of these ponds. With the increasing awareness of the unique ecological role played by the mangroves, there is an urgent need to stop the conversion of mangrove swamps into aquaculture ponds. To develop pond aquaculture without destroying the mangroves, a shift from tide-fed to pump-fed pond systems is recommended in order to divert the farming from the mangroves to higher grounds. Mangrove-friendly mariculture practices like pen, cage and raft culture are discussed. Methods of efficiently utilising the already destroyed mangrove areas are considered.     

PROTOPERIDINIUM BELIZEANUM SP. NOV. (DINOPHYCEAE) FROM MANATEE CAY,BELIZE, CENTRAL AMERICA1

A new marine heterotrophic dinoflagellate species, Protoperidinium belizeanum sp. nov., from a coral reef‐mangrove pond was identified from scanning electron micrographs. Recognition of this new species was based on unique features of the thecal morphology, which included cell size and shape, presence of short and wide postcingular plates, sulcal architecture, antapical spines, and intricate thecal plate patterns of ridged hexagonal depressions. The thecal plate formula is as follows: Po, X, 4′, 3a, 7″, 4C (3+t), 6S, 5?, 2″″. Species association of P. be‐lizeanum sp. nov. within the genus Protoperidinium, its habitat, and associated dinoflagellates species are discussed.     

中国黑斑蛙种群的线粒体DNA多样性和生物地理演化过程的初探

本文通过对黑斑蛙 8个地方种群 2 5 7个标本的线粒体基因组Cytb基因片段的序列分析 ,探讨了其种群遗传多样性的现代分布格局及其生物地理演化过程。对所检测出的 79个单倍型的分析表明 :黑斑蛙在我国分布区内中部地区的种群遗传多样性高于南北边缘种群。种群间基因流同地理隔离距离呈显著负相关 ,种群遗传分化符合距离隔离或脚踏石模型。线粒体单倍型以广西和四川种群的个体的遗传分化为最深 ,反映出西部山区的屏障隔离效应。单倍型歧点分布分析表明 ,约 10 3- 2 2 6万年前 ,即在末次间冰期 ,黑斑蛙在其分布范围内经历过一次大规模的种群扩张事件。单倍型的分布格局和共享情况显示黑斑蛙种群在冰期后的重新扩张过程主要表现为由南往北的递进式扩散形式。第四纪冰期气候的反复波动导致了黑斑蛙适宜生境在纬度方向上的平移 ,进而导致黑斑蛙种群随生境变化而进行扩张或收缩 ,使黑斑蛙种群的遗传多样性能始终保持在分布区中间高而南北两端低 ,并形成了现代的分布格局     

模拟稳定塘系统对污染指示菌的去除作用

本文研究了模拟稳定塘系统去除污染指示菌如总大肠菌群(TC),粪大肠菌群(FC),粪链球菌(FS)以及异养细菌(HPC)的作用。结果表明,16℃时污水在日进污水10t的模拟稳定塘系统停留9天后,TC与FC的密度下降4个数量级。在日进污水90t,污水理论水力停留时间10天的模拟稳定塘系统进行的全年跟踪监测结果表明,TC与FC密度随各塘依次递减。Ⅳ号塘出水的TC密度下降2.5个数量级,基本上达到了我国GB3838-88中规定的地面水Ⅲ级标准;FC密度下降3个数量级,达到WHO标准的轻污染水平,肯定了稳定塘系统去除污染指示菌的有效性。     

宽叶香蒲净化塘系统净化铅／锌矿废水效应的研究

研究了以宽叶香蒲(Typha latifolia)为优势群落的净化塘系统来处理广东韶关凡口铅/锌矿选矿废水。经5年多的监测结果表明,该系统能有效地净化铅/锌石广废水。在进入净化塘系统前,未处理的废水合有高浓度的悬浮物(4 635mg/L)和重金属[Fb(1.61mg/L)、Zn(1.96mg/L)和Cd(0.022mg/L)]等,经过净化后,水质明显改善,pH从8.03下降到7.74,总悬浮物去除率达99％,Pb去除率为90％,Zn和Cd去除率为84％,其它重金属如Cu、Fe和Al等也都有不同程度的降低。     

Fishpond dams affect leaf‐litter processing and associated detritivore communities along intermittent low‐order streams

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