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161.
考察两组微氧水解强化复合型人工湿地(MA-HCW)组合的中试反应器,对城市黑臭水体的净化处理效果。两组反应器分别种植风车草和菖蒲两种植物,运行的水力负荷为0.2 m~3/(m~2·d)。结果表明,种植风车草的人工湿地系统(A系统)的总体净化效果略优于种植菖蒲的人工湿地系统(C系统)。A系统的COD、BOD5、TN、NH_4~+-N、TP、TSS平均去除率分别为69.65%、75.2%、58.33%、38.46%、59.8%、82.1%。研究表明,微氧水解功能段有效降低了进水中TSS的浓度,起到预防湿地系统堵塞的作用。数据分析显示COD、NH _4~+-N和TN的去除率与溶解氧和温度有相关性。 相似文献
162.
Urs Gimmi Shelley L. Schmidt Todd J. Hawbaker Camilo Alcántara Ulf Gafvert Volker C. Radeloff 《Journal of environmental management》2011
Protected areas are cornerstones of biodiversity conservation, but they are in danger of becoming islands in a sea of human dominated landscapes. Our question was if protected areas may even foster development in their surroundings because they provide amenities that attract development, thus causing the isolation of the ecosystems they were designed to protect. Our study analyzed historic aerial photographs and topographical maps to reconstruct road development and building growth within and around Indiana Dunes and Pictured Rocks National Lakeshores in the U.S. Great Lakes region from 1938 to 2005, and to estimate the effects of park creation in 1966 on changes in landscape patterns. Historic U.S. census housing density data were used as a baseline to compare observed changes to. Our results showed that park establishment was effective in reducing and stopping the fragmenting impact of development within park boundaries. However, increased amenity levels following park establishment led to enhanced development in the surroundings of both parks. In the extreme case of Indiana Dunes, building density outside the park increased from 45 to 200 buildings/km2 and road density almost doubled from 3.6 to 6.6 km/km2 from 1938 to 2005. Development rates of change were much higher than in the broader landscape, particularly after park establishment. The potential amenity effect was up to 9500 new buildings in the 3.2-km zone around Indiana Dunes between 1966 and 2005. For Pictured Rocks the absolute effect was smaller but up to 70% of the observed building growth was potentially due to amenity effects. Our findings highlight the need for conservation planning at broader scales, incorporating areas beyond the boundaries of protected areas. 相似文献
163.
Wetlands research and restoration has become one of the critical concern due to their importance in providing ecosystem services. This study proposes a holistic methodology to assess the wetland ecosystem based on cosmic exergy as a thermodynamic orientor. This new approach is applied to two typical wastewater treatment facilities (an activated sludge system and a cyclic activated sludge system) and to a constructed wetland ecosystem in Beijing for comparison. Results show that the Beijing wetland ecosystem gains positive net present ecological value of 3.08E+14 Jc regarding its total life cycle. Comparison with the activated sludge system and cyclic activated sludge system, shows that the wetland ecosystem has greater dependencies on local resources (22% vs. 0% vs. 0%) and renewable resources (67% vs. 38% vs. 31%) as well as a larger ecological sustainability index (0.64157 vs. 0.00005 vs. 0.00008). This implies that the wetland ecosystem is more environmentally friendly and sustainable method for water treatment. 相似文献
164.
通过对天津南港工业区土壤环境背景值的调查研究,对其土壤进行了环境质量评价,并得出了该区域土壤元素的分布规律。在与其他地区的土壤背景值进行比较后,指出了其异同点。天津南港工业区土壤元素在垂直方向上以不规则分布型为主,但As和Cd在土壤表层和深层的含量变化差异较小,Pb表现为表层富集。水平方向上,园区西北部的土壤元素含量比... 相似文献
165.
通过采集兰州市银滩湿地秋(10月)、冬(12月)两季不同水环境中的表面沉积物,分析鉴定硅藻属种的分布和组合特征。结果表明硅藻优势种随采样点和采样时间发生变化。10月份以Gyrosigma scalproides、Cymatopleura solea var.regula、Navicula viridula var.rostellata、N.simplex、N.exigua、Nitzschia palea、N.angustata var.acuta、Cymbella affinis为相对优势种。12月份以Gyrosigma Parkerii、G.acuminatum、Navicula veneta、N.viridula var.rostellata、Nitzschia angustata var.acuta、N.palea、Cocconeis placentula为相对优势种。银滩湿地在秋季和冬季以指示淡水环境硅藻为主,底栖种和附着型种为特征。出现了一些指示中营养的有机污染种,表明了水质的营养化程度升高。有机质含量、pH、Cl-和P是中营养有机污染种主要的影响因素,表明银滩湿地的富营养化趋势较为明显。 相似文献
166.
167.
为了解西溪湿地底泥质量现状,2012年9月采集保护区内不同干扰类型的底泥样本,测试了底泥中重金属和POPs中PCBs、OCPs和PAHs的含量,并对湿地底泥污染进行了生态风险初步评价。结果表明,底泥中未检出PCBs和OCPs,但检测出14种EPA优控PAHs,总PAHs的浓度范围为115.9~217.8 ng·g^-1,低于潜在生态风险的效应区间低值ERL,其中列入中国"水中优先控制污染黑名单"的7种PAHs均有检出并且其总量占∑PAHs 1/2左右(平均为50.08%);底泥中8种重金属含量平均值低于《土壤环境质量标准》(GB 15618—1995)的二级标准,但Hg、Zn、Pb、Ni含量在多个位点已超过一级标准;分别采用土壤背景值和国家一级标准为参比值对湿地底泥中重金属进行单因子污染风险指数评价,发现分别有7种和4种元素的污染指数大于1;综合分析不同干扰类型的底泥质量,发现底泥疏浚能有效降低有机质含量、全氮和PAHs含量,但对全磷、重金属含量则无明显效果,封闭水体的干塘措施能显著减少污泥量和有机物含量。研究结果表明,西溪湿地底泥中高环PAHs和重金属污染水平可能对西溪湿地生物具有潜在的生物毒性作用及不利的生态影响效应,其疏浚底泥农用则无生态风险。 相似文献
168.
ANNE E. PUSEY§† LILIAN PINTEA‡§†† MICHAEL L. WILSON†§ SHADRACK KAMENYA† JANE GOODALL†† 《Conservation biology》2007,21(3):623-634
Abstract: Long-term research projects can provide important conservation benefits, not only through research specifically focused on conservation problems, but also from various incidental benefits, such as increased intensity of monitoring and building support for the protection of an area. At Gombe National Park, Tanzania, long-term research has provided at least four distinct benefits to wildlife conservation. (1) Jane Goodall's groundbreaking discoveries of chimpanzee (Pan troglodytes) tool use, hunting, and complex social relationships in what was then a game reserve drew attention to the area and created support for upgrading Gombe to national park status in 1968. (2) The highly publicized findings have earned Gombe and Tanzania the attention of a worldwide public that includes tourists and donors that provide financial support for Gombe, other parks in Tanzania, and chimpanzee conservation in general. (3) Crucial information on social structure and habitat use has been gathered that is essential for effective conservation of chimpanzees at Gombe and elsewhere. (4) A clear picture of Gombe's chimpanzee population over the past 40 years has been determined, and this has helped identify the greatest threats to the viability of this population, namely disease and habitat loss outside the park. These threats are severe and because of the small size of the population it is extremely vulnerable. Research at Gombe has led to the establishment of conservation education and development projects around Gombe, which are needed to build local support for the park and its chimpanzees, but saving these famous chimpanzees will take a larger integrated effort on the part of park managers, researchers, and the local community with financial help from international donors. 相似文献
169.
The National Park Service, like other natural resource management agencies, has adopted the traditional model of public administration,
which emphasizes efficiency, effectiveness, economy, and dichotomy between politics and administration. This approach is particularly
ineffective in greenline parks and increasingly inappropriate in traditional areas. In an era of ecological interdependence,
relationships with other agencies and jurisdictions and with adjacent as well as noncontiguous landowners are as important
as controlling visitors. Recreation managers need to develop more skill in negotiation, cooperation, coordination, and interpersonal
communication if they are to preserve and protect park resources. 相似文献
170.
人工湿地在雨水处理与湖泊水质改善中的应用研究 总被引:4,自引:0,他引:4
湖泊是城市生态系统重要组成部分,对城市的生态化建设具有特殊的意义。但近年来我国城市湖泊污染严重,水质堪忧。面对城市人工湖泊的水质恶化,水资源短缺等问题,我们对雨水、微污染湖泊进行了研究,结果表明雨水是一种可以利用的资源。文中介绍了雨水利用的重要性、城市雨水污染现状及城市雨水的处理与利用方法和人工湿地净化雨水补充湖水、改善湖水水质的系统设计及湿地植物选择与景观配置。 相似文献