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1.
白洋淀湿地补水的生态效益评估 总被引:2,自引:0,他引:2
对白洋淀在特别枯水年情况下,设计按最小生态水位补水、按适宜生态水位补水和不补水3种方案,对补水后湿地各类生态服务功能相比不补水(即只使用白洋淀湿地生态水权提供入淀径流)产生的变化进行计算,并运用市场价值法、类比法和影子工程法等方法,对各类服务功能变化的经济价值进行评估,得出白洋淀湿地补水的生态效益价值.结果表明:白洋淀湿地按最小和适宜生态水位补水,补水量分别为12 610×104和26 819×104 m3,补水的生态效益价值分别为57 036× 104和135 646× 104元,其中间接使用价值分别为52 255× 104和124 244× 104元,分别是直接使用价值的10.93和10.90倍;按最小和适宜生态水位补水,单位补水量的生态效益分别为4.5和5.1元·m-3,2种方案补水的生态效益都很显著. 相似文献
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4种沉水植物对白洋淀富营养化水体净化效果的研究 总被引:4,自引:0,他引:4
利用白洋淀富营养化的湖水和底泥与蓖齿眼子菜、马来眼子菜、金鱼藻和黑藻4种沉水植物分别组成室内静态模拟的生长体系,研究4种沉水植物在白洋淀富营养化环境下的生长状况,以及不同沉水植物生长体系对水体磷、氮及有机物的净化效果。结果表明:试验所用沉水植物对富营养化湖水、底泥具有一定的耐受能力,在试验条件中生长良好,长度与生物量都明显增加,并能有效地降低水体中的总磷、氨氮及总氮浓度。试验21 d后,蓖齿眼子菜、马来眼子菜、金鱼藻和黑藻所在的生长体系对水体中总磷的去除能力分别为:4.68、4.72、4.92和5.03μg·d-1·g-1,去除率分别为:83.59%、84.35%、87.84%和89.88%;对水体中氨氮的去除能力分别为:11.42、10.75、12.02和11.90μg·d-1·g-1,去除率分别为:74.98%、70.58%、78.96%和78.11%;对总氮的去除能力分别为:37.69、39.79、42.02和41.65μg.d-1.g-1,去除率分别为:79.40%、83.82%、88.51%和87.73%。沉水植物生长体系对CODcr的降解有所反复,但整体呈现下降趋势。不同沉水植物生长体系总磷、总氮含量随时间降解的拟合方程表明,水体总磷、总氮浓度随时间的变化呈负指数形式衰减。沉水植物对水体营养盐浓度的影响通过多种途径实现,底泥在营养盐的归趋中起着重要的作用。 相似文献
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白洋淀芦苇型水陆交错带水化学动态及其净化功能研究 总被引:4,自引:0,他引:4
于2007年3月-11月对富营养化湖泊一白洋淀进行了现场调查,分析了温度、溶解氧(DO)、叶绿素、总磷(TP)及其他水化学指标的动态变化规律,并讨论了它们之间的相互关系。结果表明:白洋淀芦苇(Phragmites australis var.baiyangdiansis)型水陆交错带对营养物质具有强烈的截留作用,可以达到净化白洋淀水体的效果。从水质指标的空间分布看,污染较重的府河河口区域其水体TP、化学需氧量(CODc,)含量明显高于污染较轻的湖泊中心区域,空间梯度上呈逐步递减趋势。根据水体盐度、总溶解性固体、TP及DO含量进行聚类分析,可以将采样点分为3类:Ⅰ区、污染较重河口区域;Ⅱ区、中间过渡缓冲区域;Ⅲ区、污染较轻中心区域。Ⅰ区其水体DO含量明显低于Ⅲ区,而水体盐度则明显高于Ⅲ区。通过调查发现:在8月份,白洋淀水体DO含量突然增加;相关分析表明:叶绿素含量与DO(P=0.046)及温度(P〈0.01)之间呈显著正相关关系。结合叶绿素等指标的动态变化规律,8月份左右可能是白洋淀藻类爆发的危险时期。 相似文献
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Remarkable Amphibian Biomass and Abundance in an Isolated Wetland: Implications for Wetland Conservation 总被引:3,自引:0,他引:3
《Conservation biology》2006,20(5):1457-1465
Abstract: Despite the continuing loss of wetland habitats and associated declines in amphibian populations, attempts to translate wetland losses into measurable losses to ecosystems have been lacking. We estimated the potential productivity from the amphibian community that would be compromised by the loss of a single isolated wetland that has been protected from most industrial, agricultural, and urban impacts for the past 54 years. We used a continuous drift fence at Ellenton Bay, a 10-ha freshwater wetland on the Savannah River Site, near Aiken, South Carolina (U.S.A.), to sample all amphibians for 1 year following a prolonged drought. Despite intensive agricultural use of the land surrounding Ellenton Bay prior to 1951, we documented 24 species and remarkably high numbers and biomass of juvenile amphibians (>360,000 individuals; >1,400 kg) produced during one breeding season. Anurans (17 species) were more abundant than salamanders (7 species), comprising 96.4% of individual captures. Most (95.9%) of the amphibian biomass came from 232095 individuals of a single species of anuran (southern leopard frog [Rana sphenocephala ]). Our results revealed the resilience of an amphibian community to natural stressors and historical habitat alteration and the potential magnitude of biomass and energy transfer from isolated wetlands to surrounding terrestrial habitat. We attributed the postdrought success of amphibians to a combination of adult longevity (often >5 years), a reduction in predator abundance, and an abundance of larval food resources. Likewise, the increase of forest cover around Ellenton Bay from <20% in 1951 to >60% in 2001 probably contributed to the long-term persistence of amphibians at this site. Our findings provide an optimistic counterpoint to the issue of the global decline of biological diversity by demonstrating that conservation efforts can mitigate historical habitat degradation. 相似文献
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白洋淀沉积物中磷的存在形态及垂直变化规律研究 总被引:2,自引:0,他引:2
湖泊沉积物中磷的含量及其形态分布是影响湖泊营养化进程的极为重要因素,对研究湖泊营养化等环境问题具有重要意义。采用化学连续提取分析法,对白洋淀环淀中村水域不同地点的沉积物中磷的形态及其在垂直方向上的变化进行了研究。结果表明,研究区域内,环淀中村水域表层沉积物总磷(TP)质量分数在544.424~608.197mg·kg-1之间,无机磷(IP)是沉积物中磷的主要形态,有机磷(OP)质量分数较小,约占10%~27%,无机磷中钙磷(Ca-P)占的比例相对较大,在质量分数上约占75.8%~94.1%。从各形态磷质量分数的变化范围来看,Ca-P〉OP〉Fe/Al-P;人类活动对湖泊沉积物中磷的形态及其水平和垂向变化影响很大。 相似文献
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安康湿地综合生态产业园规划 总被引:1,自引:0,他引:1
针对当前城市中各类湿地在经济建设浪潮中,受城市扩张的影响而逐步退缩、湿地内部生境破碎化愈益严重的局面,以安康市湿地公园为例,引入多种生态技术、结合造园手法,探寻一种兼顾湿地生态效益与城市社会经济效益的多元化利用模式。 相似文献
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Relationships among Isolated Wetland Size, Hydroperiod, and Amphibian Species Richness: Implications for Wetland Regulations 总被引:6,自引:0,他引:6
Joel W. Snodgrass †‡ Mark J. Komoroski † A. Lawrence Bryan JR. † Joanna Burger 《Conservation biology》2000,14(2):414-419
Abstract: Wetland development within the United States is regulated primarily by size. Decisions concerning wetland destruction or conservation are therefore based in part on three inherent assumptions: (1) small wetlands contain water for short portions of the year; (2) small wetlands support few species; and (3) species found in small wetlands are also found in larger wetlands. We tested these assumptions using data on wetland size, relative hydroperiod (drying scores), and relative species richness of amphibians in depression wetlands of the southeastern United States. We found a significant (p = 0.03) but weak (r2 = 0.05) relationship between hydroperiod and wetland size and no relationship (p = 0.48) between amphibian species richness and wetland size. Furthermore, synthetic models of lentic communities predict that short-hydroperiod wetlands support a unique group of species. Empirical investigations support this prediction. Our results indicate that hydroperiod length should be included as a primary criterion in wetland regulations. We advocate a landscape approach to wetlands regulation, focused in part on conserving a diversity of wetlands that represent the entire hydroperiod gradient. 相似文献
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人工湿地植物生物质资源能源化利用潜力评估 总被引:5,自引:0,他引:5
通过测定不同人工湿地植物的纤维素组分和热值,并采用NaOH–酶解工艺研究不同人工湿地植物水解液组分,对在人工湿地技术体系中起重要作用的湿地植物能源化利用潜力进行系统评估.结果显示,15种人工湿地植物的纤维素含量在19.78%~36.9%之间,半纤维素含量在4.51%~19.67%之间,木质素含量在10.79%~20.47%之间,具有与玉米秸秆相当的热值,其热值在14.002~17.839 MJ/kg之间.在NaOH–酶解工艺条件下,不同人工湿地植物水解液中存在5种糖类组分,主要为葡萄糖和木糖.研究表明,人工湿地植物是一种较好的生物质资源,可通过生物质固体成型燃料技术、沼气技术和燃料乙醇技术加以利用,进而建立人工湿地植物生物质资源能源化藕联利用模式.图2表2参22 相似文献
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沿海湿地生态系统健康预警指标体系的设计 总被引:1,自引:1,他引:1
依据压力-状态-响应(presure-state-response,PSR)模型,分析了沿海湿地生态系统健康的相关影响因素,通过问卷调研和专家访谈法对影响因素进行调适,并对其进行信度检测,构建了湿地生态系统健康预警指标体系,采用层次分析法确定权重;进一步将湿地生态系统健康指标体系划分为5个健康等级,以江苏省为例,给出各项指标相应的健康等级标准,并设计了反映湿地生态系统健康状况的预警灯显表,可为湿地管理和决策部门制定政策提供依据。 相似文献
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Solitary foragers can balance demands for food and safety by varying their relative use of foraging patches and their level of vigilance. Here, we investigate whether colonies of the ant, Formica perpilosa, can balance these demands by dividing labor among workers. We show that foragers collecting nectar in vegetation near their nest are smaller than are those collecting nectar at sites away from the nest. We then use performance tests to show that smaller workers are more likely to succumb to attack from conspecifics but feed on nectar more efficiently than larger workers, suggesting a size-related trade-off between risk susceptibility and harvesting ability. Because foragers that travel away from the nest are probably more likely to encounter ants from neighboring colonies, this trade-off could explain the benefits of dividing foraging labor among workers. In a laboratory experiment, we show that contact with aggressive workers results in an increase in the mean size of recruits to a foraging site: this increase was not the result of more large recruits, but rather because fewer smaller ants traveled to the site. These results suggest that workers particularly susceptible to risk avoid dangerous sites, and suggest that variation in worker size can allow colonies to exploit profitably both hazardous and resource-poor patches.Communicated by L. Sundström 相似文献
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内蒙古高原草原区湿地具有不同于典型湿地的特征,同时还兼具草原的一些特征,在保持生物多样性和珍惜物种资源方面具有不可替代的重要作用.通过样方调查,以重要值为数量特征,采用指示种分析法和多样性指数测定,对内蒙古高原典型内陆河流——锡林河中游河漫滩湿地植被群落特征及物种多样性进行了系统分析和研究.结果表明:(1)锡林河中游河漫滩湿地植被依微地形由高河漫滩向低河漫滩可分为芦苇+羊草,黄花苜蓿+无茫雀麦,灰脉苔草+早熟禾,水甜茅群落,小糠草+蒙古扁穗草等5个群落,以禾本科、菊科、豆科三大草本为主,建群种有别于典型湿地和典型草原群落.(2)植物水分生态类型以湿生、中生为主且无水生类型,具有典型湿地和草原的双重特征;(3)湿地植物群落物种多样性、均匀性和丰富度表现出相似的变化趋势,多样性和丰富度较草甸草原低但高于典型草原;(4)锡林河河漫滩湿地植物群落是典型河流湿地和典型草原之间的过渡类型.表6,参28. 相似文献
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污水湿地处理工艺优化组合设计 总被引:8,自引:0,他引:8
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。 相似文献
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辽河口湿地生态系统健康诊断与评价 总被引:3,自引:1,他引:3
综合考虑生态系统健康标准及河口湿地的生态特征,借鉴压力-状态-响应(pressure-state-response,PSR)模型,从压力、环境状态以及生物响应3方面构建辽河口湿地生态系统健康评价指标体系,并引入突变级数法,对1996年和2000年辽河口湿地生态系统健康状况进行了评价和分析。结果表明,1996年辽河口湿地生态系统健康度为0.979 1,2000年则降至0.961 8,即由健康状态转为亚健康状态,其主要原因为水资源不足和石油类污染加剧。应加强对辽河口湿地区域石油开采的管理,并合理分配利用水资源,保障湿地生态用水,促进辽河口湿地的生态系统健康。 相似文献
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由文辉 《生态与农村环境学报》1997,(3)
淀山湖是上海市唯一的淡水湖泊,面积约62km2。淀山湖湿地的形成主要是地质、地貌、气候、水文等自然因素和人类活动影响长期相互作用的结果。本文着重讨论了淀山湖湿地的生产功能和环境生态功能,并对湖泊湿地的利用与保护提供了建议。 相似文献
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Water is essential for life. In spite of the entire engineering infrastructure devoted to the treatment, regulation and beneficial uses of water, occasionally sufficient quantities and qualities of water become scarce. When this happens, just how do we decide how much less water to allocate to all of us and the activities we engage in to sustain and enhance our quality of life? This paper addresses some of the complexities of answering such a question, especially as society increasingly recognizes the need to provide flow regimes that will maintain healthy aquatic and floodplain ecosystems that also impact the economic, physical and even the spiritual quality of our lives. For we depend on these ecosystems to sustain our wellbeing. We are indeed a part of our ecosystems. We depend upon on aquatic ecosystems to moderate river flow qualities and quantities, reduce the extremes of floods and droughts, reduce erosion, detoxify and decompose waterborne wastes, generate and preserve flood plain soils and renew their fertility, regulate disease carrying organisms, and to enhance recreational benefits of river systems. This question of deciding just how much water to allocate to each water user and for the maintenance of viable aquatic ecosystems, especially when there is not enough, is a complex, and largely political, issue. This issue is likely to become even more complex and political and contentious in the future as populations grow and as water quantities and their qualities become even more variable and uncertain. 相似文献
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In this paper, we describe the development of a model for the sustainable release of e-flows from the regional water resource infrastructure (e.g., reservoirs, rivers with available water) for lake restoration and preservation, and use the model in a case study of Baiyangdian Lake, China. First, we define the sustainable environmental flows (e-flows), with an emphasis on the ecological importance of temporal variation in factors such as water level (depth). By analyzing historical data on the suitable range of water levels in the lake, we evaluated fluctuations using canonical correspondence analysis and frequency distribution analysis. The temporal variations required by the ecosystem of the lake were also assessed. Based on this approach, we developed an optimization model for sustainable release of e-flows. We used the adaptive genetic algorithm approach to solve the model and determine the required release of e-flows. Scenario analysis then provided a range of potential management strategies for the e-flows. The optimal results are helpful to the lake managers to establish sustainable e-flow release schemes for the lake restoration and preservation. 相似文献
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Light and temperature demands for growth and reproduction of laminarian gametophytes in southern and central California 总被引:6,自引:0,他引:6
The gametophytes of 9 laminarian species (4 from southern California, and 5 from central California, USA) became fertile in the unicellular stage (female gametophytes) or in a few-celled stage (male gametophytes), when appropriate temperatures and a sufficiently high quantum irradiance in the blue part of the spectrum were supplied. Vegetative growth, leading to the formation of filamentous gametophytes was light-saturated at relatively low irradiances (4 W m-2; equivalent to about 2 nE cm-2 sec-1 or an illuminance of 1000 lux), whereas 2 to 3 times this irradiance in continuous fluorescent cool white light was needed to induce the majority of the gametophytes to become fertile. An illuminance of 8300 lux did not inhibit the development of the gametophytes from southern Californian species. Egregia menziesii exhibited an exceptionally low quantum demand for induction of fertility. Gametophytes of species from central and southern California differed in regard to their temperature optimum for growth (12°C in the former, 17°C in the latter) and their upper temperature limit for reproduction (17°C in the former, 20°C in the latter). 相似文献