摘要:"植物能够吸收或降解污染物来修复受污染的土壤和水体[1-2],还能固定土壤、泥沙防止侵蚀和污染物从固体介质中释放[3]。众多无机和有机污染物都能被对其有耐性且生物量大的植物有效降解。例如,凤眼莲能吸收和净化来自金矿采掘废水的氰化物,这类废水含各种氰化物以及重金属元素的浓度达到导致生物体产生毒性效应的水平。检测表明氰化物对凤眼莲的半数致死剂量(LC50)为13mg/ L,将经过高浓度氰化物废水驯化后的凤眼莲放在野外小型湿地进行试验,结果显示这类植物对氰化物的降解效率更高。 放射性同位素试验发现氰化物分子中的C和N原子经过植物代谢合成天冬酰胺,从而将有毒性的氰化物转化为无毒的产物[4]。尾矿场也可以用植物来修复,一方面植物可以过滤污染物浓度很高的渗滤液,另一方面栽种植物可以固定边坡减少侵蚀。 将高覆盖度植被的概念应用在一个尾矿场上,通过种植北美黄杉使其全年都维持较高的蒸腾效率来减少渗滤液。 而边坡的固定首先需要在坡面安置固定、菱形的新鲜柳条编织成的笼状网格,其后覆上土壤并喷播能在生长期对固定土壤发挥作用的草本、灌木以及树木种子。 这项技术同样适用于河岸侵蚀防护。"

摘要:2008年,重庆开县因为三峡水库蓄水形成了汉丰湖。 这个人工湖泊由一个调节坝将其与三峡水库划分开。 汉丰湖消落带需要特别关注,因为这个湖位于开县新县城旁,并且临近澎溪河湿地自然保护区。 本文主要讨论了汉丰湖消落带的管理设想,特别关注生态设计原则和人工湿地。 考虑到湖泊的自然独特性,消落带的管理需要开展探索性实验。 考虑到邻近以观鸟为主要目的之一的保护区,消落带的管理必须基于生态系统设计。 考虑到邻近开县新城,基于社区的管理也是很有必要的。 流域面上和湖岸两个尺度的生态系统环境问题需要被纳入管理内容。 就消落带自身而言,可以认为生态设计应该以实现湖岸稳定、改善水质、湿地生产、保护多样性、科学教育、食物提供和农产品生产的生态目标为主。 可以通过基于社区和生态系统的方法提供对湿地价值的认识程度。 消落带湿地生态系统的服务价值会被广泛传播并且会促进开县的经济社会发展。

摘要:美国西北太平洋地区进行的哥伦比亚河河口生态系统恢复项目可以为中国三峡库区消落带的友好型利用的研究和开发活动提供借鉴经验,该项目提出了基于生态系统的理论与方法降低联邦哥伦比亚河电力系统开发活动带来的环境影响,并开展哥伦比亚河下游及河口地区的生态系统研究、保护与恢复工作。 哥伦比亚河流域的农业、工业以及水利开发等人类活动给哥伦比亚河下游至河口地区长达235km的河口湿地区域以及区域内80%的潮感淡水水系带来了严重影响,表现在食物网的破坏,大型碎屑物流的减少以及供三文鱼育幼及避难的栖息地破坏等方面。 恢复项目主要包括5个方面的目标:1)理解影响生态系统的主要控制因素,比如水利工程对湿地生态系统的影响;2)保护和恢复影响生态系统结构和功能的因素,比如重建湿地区域与主航道的连通性;3)增加生态系统结构的稳定性,比如清除入侵物种以及恢复受威胁的盐沼湿地;4)维护和增强系统过程,比如重建食物网;5)增强鲑鱼的生态系统功能,比如增加生活史多样性,提高孵化率、增长率和成活率。 为了达到以上目标,CEERP实施了一项适应性管理的一系列工程项目。 本文介绍了适应性管理的一个年度中5个循环阶段:即制定战略、决策、行动、监测/ 研究以及评估。 本文结尾处对三峡库区的生态保护和恢复工作提出了一些可供借鉴的经验。

摘要:为中国目前新建的大坝工程修建上溯型鱼道提供了科学的生态设计理念和方法,这种生态设计的理念体现了对鱼类生物性和工程学两个学科(也可称之为生物工程学或生态水力学)原理的综合运用。 鱼道是指帮助河流中鱼类上溯通过大坝等障碍的结构或装置等,人造的结构或自然的河床均可以成为鱼道的一部分而发挥作用。 河流建坝带来的一个主要问题是阻断了鱼类到达大坝上游用以产卵、育幼和摄食的栖息地的通道,降低了鱼类栖息地之间的连接度。 为了解决这个问题,最好的解决办法就是设计鱼道,在大坝设计的过程中如果能够加以改进增加鱼道设计,将能帮助鱼类顺利上溯减少其洄游途中不必要的阻碍。 鱼道的生态设计理念主要包括8个步骤:1)确定主要的重要鱼种;2)了解这些种类的生态学特征和生活习性;3)了解鱼类通道被阻断或将被阻断的区域环境特征;4)建立鱼道生态设计标准,由相关管理机构统一制定,或者根据需要对具体工程区域进行单独制定;5)提出鱼道设计的方案并确定最优的方案;6)根据需要和实际情况开展对不确定性的关键因素的调查研究,确定鱼道生态设计的标准;7)根据鱼道生态设计标准及具体区域特点进行鱼道的设计,并由当地相关部门或机构进行评估审查;8)根据设计方案进行鱼道的建设,并对鱼道建成后的效果进行监测、评估,总结经验。 针对不同的大坝和关注鱼种介绍了一系列的鱼道的类型和设计理念。 以鱼道的生态设计理念为中国开县附近澎溪河上的汉丰坝上溯型鱼道的设计提出了下一阶段的思路和工作建议。

摘要:三峡水库蓄水后形成的消落带,其生态环境既是严峻考验,也是生态机遇。 大面积消落带植被在出露的生长季节所蓄积的碳及营养物质是非常宝贵的资源,如果能加以妥善利用,就可化害为利。 针对三峡水库消落带现状及存在的问题,必须着眼于消落带的生态友好型利用。 立足消落带向增加碳汇、生物生产、环境净化等多功能生态经济效益转变的需求,探索消落带资源可持续利用的生态工程模式。 自2008年以来,在三峡库区澎溪河一级支流白夹溪消落带实施了包括基塘工程、林泽工程、鸟类生境再造等生态工程。 本文论述了针对水位变动的消落带湿地生态工程设计原则、工程实施内容,简要分析了生态工程的效益。 论文最后指出,三峡水库消落带湿地生态工程的未来努力方向是将基塘工程、林泽工程、生境再造工程与生态经济结合起来,开发消落带生态友好型利用的综合集成模式。

摘要:三峡工程全面运行之后,水文条件发生巨大变化,新形成的消涨带(海拔145~175m)原有植被大部分可能逐渐消亡。 如何重建该地段植被成为科研人员和管理部门关注的热点问题。 在文献综合分析的基础上,结合在三峡消涨带植被重建方面的前期工作,建议如下:首先对库区消涨带植被进行长期定位监测,了解新的水文条件下原有植被动态及命运,同时为消涨带植被人工重建提供备选物种;其次,评价土壤种子库恢复地上植被的潜力,结合地上植被监测结果,评价消涨带植被的自我恢复(更新)能力。 在此基础上,综合生理生态学和生活史特征,筛选植被重建适宜物种。 人工重建植被过程中,原有水田可以应用水生植物构建湿地植被;地势平缓,土壤条件较好的地段可以利用筛选的乔木、灌木和草本垂直配置构建人工植被。 此后,至少需要5年监测和评估植被重建效果。

摘要:在白洋淀富营养化水体构筑蕹菜(Ipomoeaaquatica)浮床-生物绳组合系统一段时间后,带回实验室做静态分析,研究生物绳对微生物富集后对富营养化水体的改善效果。 结果表明,蕹菜浮床、蕹菜-聚苯乙烯纤维绳组合浮床、蕹菜-麻绳组合浮床对水中TN、NH4+－N、TP和DIP均有较好的去除效果,蕹菜浮床对水中TN、NH4+－N、TP和DIP的去除率为39.09%、44.55%、63.68%和53.70%,而蕹菜-聚苯乙烯纤维绳组合浮床、蕹菜-麻绳组合浮床的去除率分别为49.46%、67.79%、54.72%、50.62%和60.43%、70.05%、71.70%、64.20%,可见组合式浮床比蕹菜浮床的氮磷去除能力更强,而且以蕹菜-麻绳组合浮床的净化效果最好。 其中,蕹菜浮床、蕹菜-聚苯乙烯纤维绳组合浮床和蕹菜—麻绳组合浮床的植物去氮贡献率分别为36. 13%、32. 15%和27. 11%,去磷贡献率分别为71. 85%、87. 07%和74.34%,表明浮床中植物吸收只去除了系统中一部分N,微生物的脱氮途径占主导作用;而对P的去除,本试验结果显示植物吸收起主要作用。 可见,该组合生态浮床是改善富营养化水体的有效方法。

摘要:阐述了双龙湖治理前水体富营养化污染状况及原因,介绍了双龙湖原位修复综合治理措施(如环湖截污、湖底生态清淤、复氧措施、边坡护理、湖滨带生态重建与景观恢复、后期监管等措施)。 对原位修复综合治理措施实施后湖水净化效果进行了研究,结果表明:原位修复综合治理措施是治理双龙湖水体富营养化的有效措施,能够为国内外城市湖泊富营养化治理提供方法和技术借鉴。

摘要:基于三峡库区自然降雨条件下3个连续雨季观测的径流试验数据,分析不同试验处理下坡耕地地表径流磷浓度及构成,探讨地表径流磷流失量的时间变化过程及分布差异。 结果表明:颗粒态磷占磷流失总磷的70%以上,是地表径流磷流失的主要形式,5~6月磷流失量达到峰值;不施肥处理小区磷流失量最高,横坡垄作小区磷流失量最低;三峡库区增加地表植被覆盖程度能够有效减少坡耕地地表径流磷流失量,减缓种植业面源污染对地表水体产生的潜在富营养化威胁。

摘要:"模拟三峡库区消落带土壤水分变化特征设置了常规生长水分条件、轻度干旱水分胁迫和水淹3个不同水分处理组,通过构建人工植被体系,对消落带适生树种枫杨(Pterocarya stenoptera C. DC. )、池杉(TaxodiumascendensBrongn)进行不同比例的配置处理,研究枫杨、池杉在不同配置和不同水分处理下的生理生化响应特征。 结果表明:不同配置对枫杨和池杉的叶绿素a、叶绿素b、SOD、POD、CAT、ASP、O2·—、脯氨酸和可溶性蛋白均没有显著影响,不同水分处理及时间对枫杨和池杉SOD、POD、CAT、ASP、O2·—和可溶性蛋白有极显著影响。 配置伊水分、配置伊时间以及配置伊水分伊时间对枫杨和池杉的叶绿素a、叶绿素b、SOD、POD、CAT、ASP、O2·—和可溶性蛋白也没有显著影响,然而水分伊时间之间的交互作用对枫杨SOD、POD、ASP和O2·—有显著影响,对池杉SOD、CAT、ASP和脯氨酸有显著影响。 本研究发现枫杨、池杉对水分逆境胁迫的生理生化响应存在差异,但都能较好地适应三峡库区消落带的水分环境。"

摘要:在温室条件下模拟三峡库区消落带夏季伏旱时土壤水分变化特征,以盆栽桑树为材料,设置对照(CK)、中度干旱胁迫(T1)和特大干旱胁迫(T2)3个含水量梯度,研究了不同程度干旱胁迫对桑树生长的影响。 结果表明:1)随着干旱胁迫的加剧,桑树的株高、地径和根表面积逐渐降低,差异显著(p <0.05);根冠比在处理初期逐渐升高,而后期逐渐降低;比根面积总体呈上升的趋势,差异显著(p <0.05)。 2)随着处理时间的延长,各处理组的株高、地径、根表面积以及根冠比呈不同程度的上升趋势;比根面积基本上呈逐渐降低的趋势。 研究结果表明,在不同程度的干旱胁迫条件下,桑树的生长受到一定程度的抑制,但能够通过合理调节自身生物量的配置,以增强吸水能力,减轻干旱伤害,维持植物体的正常生长,从而表现出一定的抗旱耐旱潜力。

摘要:基于CASA模型,利用SPOT/ VGTNDVI 数据、植被覆盖类型图、气象数据等,对三峡库区(重庆段)1998—2007年植被净第一性生产力(NPP)进行遥感估算,并对其时空特征进行了分析。 研究结果表明:1)1998年到2007年各年植被NPP的变化整体呈现波动下降的趋势;2)1998—2007年研究区植被NPP在季节变化上由高到低依次为夏季(675.705gC·m-2)、季(368.2gC·m-2)、秋季(207.944gC·m-2)、冬季(49.495gC·m-2)。 夏季植被NPP最高值出现在2000年1022.173gC·m-2),最低值主要出现在2006年(318. 321gC·m-2);3)1998—2007年,年均植被NPP值在184.8~515.548gC·m-2之间,高值主要出现在渝东北的巫溪县、巫山县、奉节县及渝东南的石柱县、武隆县等区域,低值主要在忠县、涪陵区及主城区大片区域;4)各年阔叶林单位面积生产力最高,其次为灌丛和灌草丛、针叶林、草甸、水生植被,水域生产力最低。

摘要:三峡水库蓄水后,在重庆开县白夹溪河岸设置典型消落带植被观测样地。 2008—2010年,对样地内的植物进行了3次调查。 结果表明,样地中群落组成、多样性和生物量时空变化较大。 总物种数量由2008年的52种降低至2009年的41种和2010年的35种。 2008年,156m水淹线以下植物以苍耳(Xanthiumsibiticum)和双穗雀稗(Alter-nantheraphiloxeroides)为主。 2009年,狗牙根(Cynodondactylon)替代双穗雀稗成为优势物种,苍耳向样地上部扩散。由于2009年冬季三峡蓄水提前,2010年样地下部的苍耳大大减少。 2009年和2010年植物群落多样性指数总体上表现出随着海拔升高而增加,与水淹干扰强度在空间上的变化一致。 研究结果提示,各高程区的地表生物量在3次调查中表现出较大的波动。

摘要:自2006年10月始,三峡水库已经完成了从156~175m分期蓄水过程。 为进一步了解水库分期蓄水对消落区植物群落结构和分布格局的影响,在2008年的工作基础上于2011年7~8月再次对白夹溪消落区内的植物群落进行调查,对比和分析了该区域内在156m蓄水和175m蓄水情况下消落区植物群落的结构变化。 结果表明,研究区域内共发现维管束植物39科93属101种,其中消落区内有维管束植物30科74属84种;曾经是消落区优势种的苍耳(Xanthiumsibiricum)、双穗雀稗(Paspalumpaspaloides)等植物分布范围明显减少;香附子(Cyperus rotundus)、西来稗(Echinochloacrusgali var. zelayensis)和合萌(Aeschynomene indica)成为该区域新生的优势植物种群。 该结果提示三峡水库175m蓄水对白夹溪消落区植物多样性及植物群落分布有重要影响。

摘要:以GIS为支撑,以三峡水库消落带的空间关系、高程变化和坡度分布为基础,分析了三峡水库消落带碳储量的空间格局。 结果表明,三峡水库消落带碳储量(单位:tC)约为514862.3tC;不同高程带碳储量变化由高到低依次为高程带160~170m、150~160m、170~175m、145~150m,其中高程带160~170m的碳储量最高为229367.46tC;不同坡度带碳储量变化由高到低依次为坡度带5毅~15毅、0毅~5毅、15毅~25毅,其中坡度大于25毅的区域,由于水流冲刷和基岩出露,植被生长稀少,因此不考虑其地上部分和地下部分碳储量,估算该区域碳储量为0,这也是不同高程带和不同坡度带计算出来的碳储量相差较大的原因。 研究认为三峡水库独特的调节方式和消落带植被夏季生长茂盛可吸收并积累大量碳,具有较大的碳汇潜力;同时在迭加土壤、气候、人为干扰等多种因素后,碳储量表现出了明显的沿高程梯度和坡度梯度变化的趋势。

摘要:"自2008年7月初至9月底,采用静态暗箱-气相色谱法观测了三峡水库澎溪河新生湿地4种植物群落的CO2 排放通量。结果表明,4种植物群落CO2 排放通量有明显的空间差异。藨草群落CO2 排放通量最大,其值为(627.8依335.9)mg·m
-2·h-1,灯芯草群落CO2 排放通量最低,其值为(450.4依271.5)mg·m-2·h-1。地上生物量较大的藨草群落和双穗雀稗群落具有较大的CO2 排放通量,而地上生物量较小的灯芯草群落及水烛群落CO2 排放通量较小。与植物呼吸作用相关的地上生物量等生态因子有助于解释不同湿地植物群落CO2 排放通量的差异。澎溪河新生湿地CO2 排放通量具有典型的时间动态,即7月中旬到8月中旬之间CO2 排放通量最大。水温和土壤(5cm深度)温度与CO2 排放通量显著相关(r =0.577,0.557,p <0.001),湿地地表积水和湿地土壤温度季节变化可以解释澎溪河新生湿地CO2排放通量的时间变化。"

摘要:Plants can be used to remediate polluted soil or water ( phytoremediation) by extracting and / or degrading pollu-tants[1-2]and for stabilization of soils and ediments[3](phytostabilization) in order to prevent erosion and to minimize the re-lease of contaminants from the solid matrix. A broad range of inorganic and organic pollutants can thus be processed by usingsuitable plants that are tolerant of the pollutants, generate high biomass, and are effective in uptake. As an example, water hyacinths can be used for extracting and degrading cyanide from gold mining process water that usually contains cyanide spe-cies and heavy metals in concentrations of toxicological concern. We determined a lethal dose (LC50) of about 13 mg cya-nide / L for the water hyacinths and observed that under field conditions in a pilot scale wetland the plants became more effec-tive after several applications in degrading cyanide even at high concentrations. Experiments with radio-labelled cyanide re-vealed that the carbon and nitrogen of cyanide in the plants were used to biosynthesize asparagine; thus the toxic cyanide was effectively transformed into a non-toxic, natural product[4]. Waste disposal sites can be remediated with plants both with re-spect to leaching - the percolating water may contain high concentrations of pollutants and with respect to the stabilization of slopes in order to reduce erosion. We used the concept of dense vegetation on an industrial waste site and grew douglas firs that perform high evapo-transpiration rates throughout the year and thus reduce the amount of leachate from the dump site.For stabilization of the slopes it is possible to first install a stable, diamond-shaped network of living plants (willows), levelup the network with soil and spray a mixture of suitable seeds of grass, shrubs or trees (truck wet application) which will further stabilize the soil during growth. This technique can be applied also to river banks for erosion control.

摘要:"Abstract: In 2008 Hanfeng Lake was created in Kai County, Chongqing, by the filling of the reservoir associated with the Three Gorges Dam. The lake is partially separated from the Pengxi River by a water-level regulatory dam, and is surrounded by urban development. The drawdown zone of Hanfeng Lake requires special attention because of its urban location and the status of the lake as a nature reserve. Here we discuss some of the management issues for the drawdown zone, with special consideration to eco-design principles and engineered wetlands. Given the unique nature of the lake, we argue that manage-ment of the drawdown zone requires an approach that is experimental and therefore adaptive. Given that the nature reserve objectives include a focus on bird abundance and diversity, we argue that the management approach must be ecosystem-based. Given the urban location, we argue that community-based processes must be used for the management approach to be socially acceptable. We consider that the effective ecosystem is the watershed of the lake and that both large-scale and local zoning are necessary management tools. Within the drawdown zone itself, we consider that eco-design principles can be ap-plied to achieve the provision of valuable ecosystem services including: bank stabilization, improved water quality, wetland productivity and biodiversity, natural science education, food production, and agricultural education. By taking these community-based and ecosystem-based approaches to raising awareness about the values provided by wetlands, natural ecosystem services will be delivered and these will promote the sustainable economic and social development of Kai County."

摘要:"The ColumbiaEstuaryEcosystemRestorationProgram(CEERP)intheU. S. PacificNorthwest providesprogram-
matic processes,experiences,andlessons applicable to the eco-friendly utilizationof the littoral zone inthe Three Gorges Reservoir (TGR)inChina. The CEERPapplies anecosystem-basedapproachto helpmitigate the environmental effects of theFederal ColumbiaRiver Power stembyworkingtounderstand,conserve,andrestoreecosystemsinthelower Columbia
River andestuary (LCRE). Wetlandecosystems inthe LCRE,whichis235kmlong andabout 80%tidal freshwater,have beenalteredsignificantly by agricultural,industrial,hydrosystemoperations,andother practicesthat disrupt foodwebs,re-duce macrodetritus flux,andrestrict rearingandrefugeareasfor juvenilesalmon,amongother consequences. Therestoration programhas five mainobjectives:1)understandthe primary stressors affecting ecosystemcontrolling factors,e. g. ,diking restricting access to andcontributions fromwetlandecosystems;2)conserve andrestore factors controlling ecosystemstruc-tures andprocesses,e. g. ,reconnecting wetlandareas to the mainstem;3) increase the quantity andquality of ecosystem structures,e. g. ,removing invasive plants andrestoring emergent rshes;4)maintainandenhance ecosystemprocesses,e. g. ,revitalizing foodwebs;5)improvetheecosystemfunctionof salmonperformance,e. g. ,increasinglife-historydiver-sity,foraging success,growth,andsurvival. To accomplishthese objectives,the CEERPimplements anadaptive manage-ment process ledby the funding agencies andperformedincollaborationwithregional stakeholders. This paper uses the five phases of the annual CEERPadaptive management cycle—Strategize,Decide,Act,Monitor/ Research,andEvaluate—as the context for presentingkeyresultsfromtheprogram. Thepaper closeswithlessonstoconsider for ecosystem-basedconser-vationandrestorationinthe Three Gorges Reservoir."

摘要:"This paper provides a scientific approach for the eco-design of river fishways to allow upstream movement of fish past new and existing dams in China. This eco-design approach integrates principles of fish biology and engineering, a scientific field also known as bio-engineering or eco-hydraulics. We define a fishway as a structure or mechanism for conveying fish upstream past a dam. Man-made or natural stream beds can be part of the fishway. The problem is dams block access to upstream habitat used for spawning, rearing, and refuge; i. e. , dams decrease habitat connectivity. A solution to alleviate this problem is to design fishways, preferably while the dam is being designed, but if necessary, as retrofits afterward to provide a route that fish can and will use to pass safely upstream without undue delay. Our eco-design approach for fishways involves eight steps: 1) identify the primary species of importance; 2) understand the basic ecology and behavior of these fish;3) characterize the environmental conditions where passage is or will be blocked; 4)establish eco-design criteria for the fishway, either from management agencies or, if necessary, developed specifically for the given site; 5)identify fishway alternatives and select a preferred alternative; 6) where needed, identify and perform research required to resolve critical uncertainties and finalize the eco-design criteria; 7) apply the eco-design criteria and site-specific considerations to design the fishway, involving peer-review by local stakeholders in the process; 8) build the fishway, monitor its effectiveness, and apply lessons learned. Types of fishways are described, showing a range of eco-designs depending on the dam site and fish species of concern. We use the eco-design principles as a basis to recommend an approach and next steps for a fishway to pass fish upstream at Hanfeng Dam, an existing regulating dam forming Hanfeng Lake on the Pengxi River near Kaixian, China."

摘要:The Three Gorges Reservoir (TGR) provides the benefits of flood control, electricity generation and improved transportation along the river corridor. For the purpose of flood control, the reservoir height varies between 145 m and 175 m above sea level, creating a reservoir littoral zone of about 350 km2 in total area distributed along more than 1200 km of shoreline. Most of the littoral zone is flooded during October to May and relatively dry during the remainder of the year. Water level regulation has caused marked ecological changes in the littoral zone of TGR. The littoral zone formed after impounded by TGR not only is the crucible to us, but also the ecological opportunity. The vegetation of large-scale hydro-fluctuation belt is a very valuable resource, if properly used, can turn harm into advantage. In view of the current status and existing problems of the littoral wetland in TGR, we should focus on utilizing resources of the littoral wetland eco-friendly. Based on the needs for the littoral wetland transform into the multifunctional ecological economic benefit such as increasing carbon sources, biological production, and environmental purification, we must develop the ecological engineering model of sustainable utilizing the wetland resources of the littoral zone. In view of the environment problems of TGR and its characteristics of water level fluctuation, the ecological engineering focusing on restoration of littoral wetlands have been carried out since 2008. The eco-logical engineering was mainly conducted at littoral wetlands in Baijia stream of Pengxi River of TGR, including dike-pond system, submergence tolerance wetland-woods and waterfowl habitats recreate projects. The design principle and process for the ecological engineering of littoral wetlands restoration under the condition of the periodic water level change was described in details in this paper. Effects of the ecological engineering and the benefits to the environments were assessed. In the end of the article we proposed that the ecological engineering focus on the restoration of littoral wetlands, also should consider uti.

摘要:After the full functioning of the Three Gorges Dam (TGD), the hydrologic regime will be markedly changed and most of the pre-dam vegetation in the new Water-Level Fluctuation Zone (WLFZ) may fail to persist. How to revegetate WLFZ of the Three Gorges Reservoir Region (TGRR) has become a hot topic for the scientific community and the governments. Based on review of scientific literature and the findings of our research, we here bring forward a scheme addressing strategies for revegetation of WLFZ of TGRR. Firstly, monitor vegetation dynamics based on permanent plots along the Three Gorges upstream from TGD, potentially providing suitable plants for the future revegetation plans. Secondly, examine the potential of soil seed bank for revegetation of the above-ground vegetation, and evaluate self-regeneration of the post-dam vegetation. Based on these data, select suitable plants for revegetation that integrate desirable physiological and life-history traits.Specifically, wetland vegetation could be constructed with lotus (Nelumbo nucifera) and aquatic plants. For sites with gentle terrain and fairly hospitable soil conditions, vertical planting of trees, shrubs and grasses / forbs along the elevation gradient could be considered. To attain the sustainable vegetation cover, the newly artificial vegetation should be monitored for at least 5 years.

摘要:Recently, lake eutrophication has become a serious concern and its causes and controls have attracted growing attention worldwide. In the experiments described here, we have used Ipomoea aquatica as an experimental plant for use with ecological floating beds. Three kinds of combined ecological floating bed systems were constructed by hanging two kinds of rope (hemp and PST) below the beds, and their effectiveness for improving water quality was investigated. The results showed that the plant ecological floating bed, plant-PST- rope combined bed, and plant-hemp-rope combined bed provided significant removal effects on TN, NH4+-N, TP and DIP. Removal efficiencies were 39. 09%, 49. 46% and 60. 43%, 44% 55%, 67. 79%and 70. 05%, 63. 68%, 54. 72% and 71. 70%, and 53. 70%, 50. 62% and 64. 20%, respectively. The plant-hemp-rope combined floating bed had especially high N and P removal rates. In the three kinds of ecological floating beds, the contributions of plant absorption to N and P removal were 36. 13% and 71. 85%, 32. 15% and 87. 07%, 27. 11% and 74. 34%, respectively. This suggested that for N removal in the system, plant uptake accounted for a relatively small portion of total absorption, and that denitrification by microorganisms might play a more important role. However, plant uptake took the leading role in P removal in all three kinds of floating beds. Therefore, the combined ecological floating bed having both ropes and plants was an effective way for improving the quality of eutrophic water.

摘要:This paper describes the pollution condition and causes of the eutrophication of Shuanglong Lake prior to its management and introduces measures for comprehensive in situ repair (such as lake interception, ecological dredging, reoxygenation measures, slope care, ecological reconstruction and landscape restoration of the lakefront, later-stage management, and other measures). The study reports the effects of water purification after the implementation of these comprehensive in situ repair measures. The results show that these repair measures have been effective in controlling the eutrophication of Shuanglong lake, and this study therefore provides methods and technical reference for the management of urban lake eutrophication at home and abroad.

摘要:Using the "Winter Wheat-Summer Maize" model and the plot runoff monitoring method, we studied the characteristics of nitrogen and phosphorus loss in the soil sediment of purple sloping farmland under five conditions, including control,combined manure / fertilizer application, chemical fertilizer, high intensity chemical fertilizer, and cross ridge farming. The results showed that the nutrient content of the surface soil increased, to some extent. Furthermore, the nutrients were enriched in the sediment for all groups. The degree of sediment nutrient enrichment of cross ridge farming was less great compared to longitudinal farming. For the combined manure / fertilizer application, the ratio of effective nutrients was larger than that of total nutrients; whereas, for the chemical fertilizer group, the ratio of effective nutrients was significantly smaller. At all fertilization levels, sediment loss only accounted for 0. 34% ~ 6. 21%. 78. 80% ~ 84. 83% of the total phosphorus loss occurred in the sediment, and the phosphorus loss was largely in the sediment. The relative loss factor of nitrogen was the largest for the chemical fertilizer group, followed by the cross ridge farming group, the high intensity chemical fertilizer group, and the combined manure / fertilizer application group. The relative loss factor of phosphorus was the largest for the high intensity chemical fertilizer group, followed by the cross ridge farming group, the chemical fertilizer group, and the combined manure / fertilizer application group.

摘要:Three different kinds of water treatment and two configuration modes were applied to examine the biochemical and physiological responses of P. stenoptera and T. ascendens saplings under simulated vegetation of the Hydro-fluctuation Belt of the Three Gorges Reservoir Region. The water treatments were normal growth water condition ( CK), light drought water stress (LD) and water submersion (SM). The first configuration mode was 3 P. stenoptera and 6 T. ascendens, and the second was a reverse of the number of saplings of both species. The results showed that different configuration modes could not significantly influence the photosynthetic pigment, SOD, POD, CAT, ASP, O2·—, proline and soluble protein of the two species. In contrast, different water treatment and time had significant influences on SOD, POD, CAT, ASP, O2·— and soluble protein of the two species. The interaction of configuration modes x water treatment, configuration modes x time, configuration modes x water treatment x time had no significant influence on photosynthetic pigment, SOD, POD, CAT, ASP, O2·— and soluble protein of the two species. However, the interaction of water treatment x time had significant influences on SOD, POD, ASP and O2·— of P. stenoptera, as well as on SOD, CAT, ASP and proline content of T. ascendens.Our study showed that both species had to some extent different biochemical and physiological responses to water stress, and were relatively well-adapted to the dynamic hydrological environment in the hydro-fluctuation belt of the Three Gorges Reservoir Region.

摘要:"To examine possible effects of soil water conditions in summer in the hydro-fluctuation belt of the Three Gorges Reservoir Area on mulberry, we grew potted mulberry in a greenhouse under three soil water regimes designed to simulate normal irrigation (CK), moderate drought stress (T1) and elevated drought stress (T2). The results showed the following.1) With drought stress increasing, the heights, base diameters, and root surface areas of mulberry trees decreased significantly relative to the corresponding earlier period. The root / shoot ratio increased gradually in the earlier stage, and decreased gradually in the later stage. The specific root area of mulberry trees on the whole increased significantly relative to the corresponding earlier period. 2) With the elongation of treatment time, the growth of mulberry seedlings decreased gradually, and the heights, base diameters, root surface area and root / shoot ratio of the mulberry trees in the three treatment groups increased to different degrees. The specific root area of mulberry trees on the whole decreased gradually. We concluded that under the different degrees of drought stress the growth of mulberry trees would be inhibited, but the plants were also able to adapt to the stress, thereby maintaining physiological and metabolic viability. Biomass appeared to be re-allocated such that
water absorption capacity was improved. Accordingly it can be concluded that the mulberry trees demonstrated potential for resisting and tolerating drought stress."

摘要:"Based on the CASA model, we report a remote sensing estimation of net primary productivity (NPP) during 1998 to 2007, using SPOT/ VGT NDVI data, vegetation-type coverage, as well as meteorological and other data, and we analyze its spatiotemporal characteristics. Results show that: 1) the volatility of NPP during 1998 to 2007 drops on the whole. 2) Seasonal variation of NPP during 1998 to 2007 shows the following regularity: summer (675. 705 gC·m-2) > spring (368. 2 gC·m-2) > autumn (207. 944 gC·m-2) > winter (49. 495 gC·m-2). In summer, the maximum value of NPP (1 022. 173 gC·m-2) occurred in 2000; the minimum value of NPP (318. 321 gC·m-2) occurred in 2006. 3) NPP values in the research region varied between 184. 8 and 515. 548 gC·m-2 during 1998 to 2007. High values were mainly distributed in northeast Chongqing, such as Wuxi,Wushan, Fengjie, and in south east Chongqing, such as Shizhu, Wulong and others. Low values were distributed in Zhongxian, Fuling and most of the main urban areas. 4) The highest productivity per unit area was found in regions of broad-leaved forests.Productivity was progressively lower in the following vegetation classifications: bush fallow and irrigated grass vegetation, coniferousforest vegetation, grassy marshland, aquatic vegetation, and water area."

摘要:"After impoundent of the Three Gorges Reservoir, a large permanent sample plot was placed in its water-level-fluctuation zone beside Baijia Stream, Kaixian County, China. Vegetation in the plot was investigated in the summer of 2008,2009 and 2010. The result indicated that community’ s component, biodiversity and aboveground biomass showed obvious spatial-temporal dynamics. Total spiecies number of vascular flora inside decreased yearly, from 52 species in 2008 to 41 species in 2009 and to 35 species in 2010. The area below 156 m in elevation was dominated by Paspalum paspaloides and Xanthium sibiricum in 2008. However, Paspalum paspaloides was rapid replaced by Cynodon dactylo in 2009 and X. sibiricum expanded its distribution in upper area of the plot. In 2010, X. sibiricum depressed its population in lower areas of the plot as the Three Gorges Reservoir started to impound half month earlier in the winter of 2009 and decreased seed bank for its germination. Shannon-Wiener Index increased as elevation according to the data of 2009 and 2010, which reflected the influ-ence of submerged gradient. Aboveground biomass of vegetation in each elevation zone of the plot indicated great variation.Key words: Three Gorges Reservoir; water-level-fluctuation zone; vegetation; spatial-temporal dynamics; biodiversity"

摘要:"Since October of 2006, the Three Gorges Reservoir (TGR) has finished the impoundment from 156 m to 175 m.In order to find the influence of the impoundment to the plant community and its爷 pattern in the drawdown zone further, an investigation on the plant community of the Baijia Creek was conducted again from July to August 2011. The plant community and its’ pattern under the influence of impoundment at 175 m was compared to the 156 m. The results show 101 species of vascular plant belong to 39 families, 93 generas have been investigated, among which 84 species belong to 30 families, 74generas distributed in the drawdown zone. The distribute area of Xanthium sibiricum and Paspalum paspaloides, which once were dominant species in the drawdown zone, decreased obviously. Cyperus rotundus, Echinochloa crusgali var. zelayensis,and Aeschynomene indica come to be new dominant species in the study area. The impoundment of the TGR to 175 m influenced the plant community and its爷 pattern in the drawdown zone significantly."

摘要:"The spatial patterns of carbon storage were analyzed based on GIS and the natural environments in the drawdown area of the Three Gorges Reservoir (TGR). The results showed that carbon storage in the drawdown area was 514 862. 3 tC and the area is gradually playing a role as a regional carbon sink. Carbon storage changes along the elevation grade, with 160 ~ 170 m above mean sea level having the largest carbon storage at 229 367. 46 tC and other elevations following in the order: 160 ~170 m>150 ~ 160 m>170 ~ 175 m >145 ~ 150 m. Carbon storage was zero in areas with greater land slopes (>25°) due to water erosion and exposed bedrock leading to sparse growth of vegetation. In different slope zones, carbon storage was in the sequence: 5° ~ 15°>0° ~ 5°>15° ~ 25°. On the whole, due to the regulation and operation modes of TGR the drawdown zone had luxuriant vegetation in summer, which had uptake and accumulation of large carbon and had big carbon sequestration potential.Under these conditions, the distribution of carbon storage along the elevation grade and the slope grade in drawdown area of TGR are deeply affected by the soil, climate, human impacts and others."

摘要:From early July to late September 2008, we studied CO2 emissions from 4 different stands in newly created marshes of the Pengxi River, using static opaque chamber-GC techniques. The results showed high spatial variation of CO2 emissions among the four stands. The greatest CO2 emission (627.8 ± 335.9 mg·m-2·h-1) was observed in the Scirpus triqueter stand. The smallest CO2 emission (450.4 ± 271.5 mg·m-2·h-1) was observed in the Juncus amuricus stand.Standing water depths and above-ground biomass were important factors in explaining these spatial variations in CO2 emissions. We also found a typical seasonal variation of CO2 emissions in this area, with maximal emissions ranging from mid-July to mid-August. The seasonality of CO2 emissions in the newly created marshes was found to be closely related to water temperature and soil temperature (r = 0.577, 0. 557 (5 cm),p < 0.001).