人类活动对安庆沿江湖泊湿地影响的初步研究

湖泊湿地不仅具有丰富的资源,还有着强大的环境功能和生态效益。人类大规模的开发利用湖泊湿地资源,在获取大量生产、生活资料的同时,也给湖泊湿地生态系统带来了负面影响,如湖面减少,水质下降,生态环境退化等。安庆沿江湖泊湿地为省级自然保护区,相对长江中下游大湖普遍退化而言,该湿地有着良好的自然性,正吸引着有关专家和研究组织的重视和关注。对安庆沿江湖泊湿地资源和功能展开分析,并从水利建设、围湖垦殖、森林砍伐和水土流失、农业污染、公路建设及渔业开发等方面探讨了人类活动对湿地的影响。提出了保护安庆沿江湖泊湿地资源和环境的建议和对策,以促进湿地资源与环境的可持续发展。     

Spatial-temporal analysis of wetland landscape pattern under the influence of artificial dykes in the Yellow River delta

The influence of anthropogenic activities,especially artificial dykes,on the coastal wetland landscape is now considered as a serious problem to the coastal ecosystem.It is important and necessary to analyze changes of coastal landscape pattern under the influence of artificial dykes for the protection and management of coastal wetland.Our study aimed to reveal the quantitative characteristics of the coastal wetland landscape and its spatial-temporal dynamics under the influence of artificial dykes in the Yellow River delta(YRD).It was analyzed by the methods of the statistical analysis of landscape structure,five selected landscape indices and the changes of spatial centroids of three typical wetland types,including reed marshes,tidal fiats and aquaculture-salt fields.The results showed that:(1)Reduction of wetland area,especially the degradation of natural wetlands,had been the principal problem since the dykes were constructed in the YRD.The dykes created conditions for the development of artificial wetlands.However,the new born artificial wetlands were still less than the vanished natural wetlands.(2)Compared with the open area,the building of artificial dykes significantly speeded up the changes of landscape patterns and the aggravation of the landscape fragmentation in the closed area.(3)The changes of area-weighted centroids of three typical wetland landscapes were greatly affected by dykes,and the movement of the centroid of the aquaculture-salt field was very sensitive to the dykes constructed in the corresponding period.     

China's coastal wetlands: Conservation history,implementation efforts,existing issues and strategies for future improvement

China has approximately 5.80 × 10⁶ ha coastal wetlands by 2014, accounting for 10.82% of the total area of natural wetlands. Healthy coastal wetland ecosystems play an important role in guaranteeing the territory ecological security and the sustainable development of coastal zone in China. In this paper, the natural geography and the past and present status of China's coastal wetlands were introduced and the five stages (1950s–1970s, 1980s–1991, 1992–2002, 2003–2010 and 2011–present) of China's coastal wetlands conservation from the foundation of the People's Republic in 1949 to present were distinguished and reviewed. Over the past decades, China has made great efforts in coastal wetland conservation, as signified by the implementation of coastal wetland restoration projects, the construction of coastal wetland nature reserves, the practice of routine ecological monitoring and two national wetland surveys, the promulgation of local wetland conservation statutes and specific regulations, the coordination mechanism to enhance management capacity, the wide development of coastal wetland research and public participation, and the extensive communication to strengthen international cooperation. Nonetheless, six major issues recently emerged in China's coastal wetland conservation are evidently existed, including the increasing threats of pollution and human activities, the increasing adverse effects of threaten factors on ecosystem function, the increasing threats of coastal erosion and sea-level rising, the insufficient funding for coastal wetlands conservation, the imperfect legal and management system for coastal wetlands, and the insufficient education, research and international cooperation. Although the threats and pressures on coastal wetlands conservation are still apparent, the future of China's coastal wetlands looks promising since the Chinese government understands that the sustainable development in coastal zone requires new attitudes, sound policies and concerted efforts at all levels. The major strategies for future improvement of China's coastal wetland conservation include: exploring effective measures in response to major threaten factors; improving the conservation and compensation system for coastal wetlands; strengthening coastal wetland legislation and management; increasing funds for coastal wetland conservation and research; and strengthening coastal wetland education and international cooperation.     

The valuation of wetland conservation in an urban/peri urban watershed

This study estimates the social benefits of wetland conservation in the Credit River watershed, located in an urban/peri urban area in Southern Ontario, Canada. A stated preference approach was employed to value wetland conservation programs which ranged from retaining the existing wetlands to restoring various levels of acres of wetlands over the 2009–2020 period. A total of 1,407 households completed an internet-based survey which presented trade-offs in binary choice scenarios framed as referenda. Responses were analyzed using various models, one of which was a latent class analysis which segmented respondents into three classes. This econometric approach uncovered significant preference heterogeneity for wetland conservation. Assignment of respondents to the classes suggested that about one-third of the sample was willing to pay small amounts to retain the existing wetlands. An additional third was willing to pay several hundred dollars a year for retention and small positive amounts for additional restoration. The final third were apparently willing to pay considerable sums for retention, but lesser amounts for additional restoration. However, further analysis revealed that respondents in this third class largely constituted yea-sayers. These results suggest caution in interpreting associated economic valuation estimates and highlight the importance of attempting to understand hypothetical bias in wetland and other such valuation studies.     

Policy on wetland impact mitigation

Important policy issues concerning the mitigation of impacts from construction and development affecting wetlands are under examination by the U.S. Congressional Office of Technology Assessment, the Environment and Public Works Committee of the U.S. Senate, and the National Wetlands Technical Council. The issues divide into two main parts: (1) how the current strategy to simplify federal regulation of wetlands is limiting the success of mitigation; and (2) how to change the present strategy for mitigation under the U.S. Clean Water Act, if at all. Requirements for site-specific analysis of impacts and their mitigation requirements are being replaced by simple, uniform national guidelines on impact mitigation; these guidelines are designed to streamline the regulatory process in which the proposed activities typically generate only minor impacts. This trend ignores how the intrinsic values of the affected wetland modify the actual severity of impact. A change in regulatory strategy may be necessary so that the efforts at impact mitigation are scaled to wetland values as well as the magnitude of adverse effects normally expected with particular activities.     

Artificial wetlands and water quality improvement

This paper illustrates the role of plants to assist the treatment of water pollution in man-made wetlands in tropical and temperate climates. It also considers the potential for environmental education of these wetland systems. The management and natural treatment of pollution is described in the Mai Po Marshes, Hong Kong and a wetland in London which is also an important site for birds. The design of the Putrajaya Lake and Wetland system in Malaysia is compared with a constructed wetland and lake for the treatment of urban surface runoff in a new residential development in the United Kingdom. The benefits of these natural systems are discussed in the context of the global trend for introducing sustainable methods of environmental management and low cost pollution treatment systems.     

城市湿地损失和内涝灾害响应的遥感分析——以武汉市南湖为例

随着快速的城市化,城市湿地不断转化成建设用地,这打破了城市水量循环的均衡,城市内涝灾害的敏感性和危害性随之提高。选取城市快速扩张的武汉市南湖地区,基于1988～2015年近30 a南湖湿地多时相遥感影像,以武汉市南湖2016年7月内涝灾害为对象,运用遥感和GIS手段,分析南湖湿地损失过程、驱动因素以及城市涝灾害的响应情况。结果表明：（1）1988~2015年间南湖湿地持续损失,累计消减1 563 hm2;南湖湿地损失经历了快速损失（1988~1996）急剧损失（1996~2004）缓慢损失（1996~2010）相对静止（2010~2015）的4个阶段,每个阶段南湖湿地转化为建设用地量分别为35.3、135、30、5.4 hm2;损失过程从南湖湿地北部开始,逐渐向南部蔓延;（2）环湖地区房地产发展是湖泊湿地损失的主要原因,52%的损失湿地转换为住宅用地;（3）85.7%的内涝灾害区域位于原湖泊湿地内;南湖地区海拔较低,随着住宅用地以及其他建设用地对湖泊湿地的侵占,南湖地区不透水面面积增加,湿地蓄水排水能力下降,在降雨量较多的时段,原湖泊湿地区域更容易受到内涝侵袭。 关键词： 城市湿地; 湿地损失; 内涝灾害; 武汉市南湖     

基于重力空间熵的城市湿地压力模型构建研究——以武汉南湖湿地为例

城市化进程中人口和建设用地需求增加引发的湿地退化压力日益凸显,熵理论为城市扩张、土地利用结构变化和城市湿地退化压力建模研究提供了新思路。已有研究表明,城市湿地损失、湿地区域建设用地的增加会导致土地利用结构空间熵的数值不断下降,但仅依靠空间熵理论难以定量湿地退化压力。因此依据城市地理学中的重力递减理论,引入距离因素,从湿地区域土地利用空间熵、湿地本身面积、距湿地中心的距离、距商业中心的距离4个要素构建重力空间熵的城市湿地压力模型。研究以1988年武汉南湖湿地遥感影像为基础,制作矢量图,从南湖湿地周边众多湖泊湿地中,随机选取40个样本湿地,分别计算了1988年、1992年、1996年、2000年、2004年5个时期的样本湿地压力值,并利用Kriging空间插值对南湖湿地所受的压力值分布进行可视化处理。结果表明：（1）湿地所在区域土地利用空间熵越小,湿地所承受压力越大;距中心湿地越远越靠近城市商业中心且面积越小的城市湿地更容易发生消亡;（2）根据城市湿地压力模型计算的压力值大的湿地更容易在下一阶段发生显著的损失或消亡;（3）随着城市化的推进,建设用地的扩张,城市湿地承受的压力值逐年增加,当压力值到达0.7左右,湿地存在极大消亡风险。遥感影像解译的结果与按照重力空间熵的城市湿地压力模型计算结果一致,说明该模型能较好地预测城市湿地在城市扩张压力下的演化过程。模型的建成对于城市湿地动态变化和保护规划具有重要意义,了解并把握这一湿地损失过程和趋势,预测城市湿地在城市扩张压力下的演化过程能为城市管理者对城市湿地的具体保护提供方向和指导。 关键词： 城市湿地; 重力空间熵; 压力模型; 城市扩张划具有重要意义,了解并把握这一湿地损失过程和趋势,预测城市湿地在城市扩张压力下的演化过程能为城市管理者对城市湿地的具体保护提供方向和指导。 关键词： 城市湿地; 重力空间熵; 压力模型; 城市扩张     

Policy design for a multifunctional landscape

Landscapes consisting of several elements, such as wetlands and forests, are multifunctional in nature and produce both market and non-market goods. The need for policies arises from the existence of non-market ecosystem services that are not traded and thereby generally not subject to economic trade-offs in landowner decision making. An efficient incentive scheme for producing both types of goods would require policy designed for each non-market good. However, this may result in high transaction costs, possibly giving second-best solutions a comparative advantage when only one non-market good is regulated. This paper demonstrates that in the Hovran catchment area in mid Sweden, which produces the non-market goods water quality, biodiversity, and scenic beauty, compensation payments for biodiversity production alone provide almost maximum total net value of all market and non-market goods. On the other hand, payments for providing scenic beauty in the form of open landscape may result in lower total net value than no compensation payment at all, due to a negative impact on water quality.     

Regional climate sensitivity of wetland environments in Rwanda: the need for a location-specific approach

Wetlands are sustaining large communities of people in Rwanda where 10 % of its land surface consists of many local wetlands. Sustainable future management of these numerous wetlands requires a reliable inventory of their location and a dynamic quantitative characterization that allows assessment of their climate change sensitivity. The aim of this study was to assess the importance of climatic factors for determining wetland location at different regional scales. Wetland locations were analyzed and statistically modeled using their location factors with logistic regression. Wetland location probability was determined using topographic (elevation, slope), hydrological (contributing area) and climatic (temperature and rainfall) location factors. A wetland location probability map was made that demonstrated a calibration accuracy of 87.9 % correct at national level compared to an existing inventory, displaying even better fits at subnational level (reaching up to 98 % correct). A validation accuracy of 86.2 % was obtained using an independently collected dataset. A sensitivity analysis was applied to the threshold values used as cutoff value between wetland/non-wetland, demonstrating a robust performance. The developed models were used in a sensitivity scenario analysis to assess future wetland location probability to changes in temperature and rainfall. In particular, wetlands in the central regions of Rwanda demonstrate a high sensitivity to changes in temperature (1 % increase causes a net probable wetland area decline by 12.4 %) and rainfall (+1 % causes a net increase by 1.6 %). This potentially significant impact on wetland number and location probability indicates that climate-sensitive future planning of wetland use is required in Rwanda.     

Estimating Ecological Value of Small Hydropower Using Contingent Valuation Method:An Application to Tongjiqiao Reservoir in Zhejiang Province,China

The small hydropower(SHP) will be less competitive in the absence of environmental value.The lack of information has become an important obstacle challenging decision-makers in resource-use choices.This paper is an application of contingent valuation method(CVM) in rural China to estimate the willingness-to-pay(WTP) for environmental services provided by exiting hydropower station.Using the single-bounded and dichotomouschoice CVM,the ecological value of Tongjiqiao Reservoir(TJQR) is estimated,and the annual mean WTPs of single-bounded and double-bounded CVM estimation are 141.05 and 219.52 Yuan(RMB)/a,respectively.The 95% confidence interval of annual WTP on an average is 118.47,166.79 Yuan(RMB)/a and 204.41,236.22(Yuan RMB)/a,respectively.In contrast,double-bounded model could obtain much more information of WTP of the investigated,thus reducing the confidence interval of estimation,and enhancing the estimation accuracy of the WTP.According to the estimated mean WTP of the double-bounded CVM,the total ecosystem service value of the TJQR is 15.54 million Yuan(RMB).Compared with the conventional electricity of fossil power and large hydropower,the SHP will be less competitive in the absence of non-market value,ignoring that the environmental impacts of existing SHP will undermine the healthy development of clean energy sector.     

Conflicts between stakeholder groups affecting the ecology and economy of the Segara Anakan region

This study analyses how the conflict potential between different stakeholder groups is affecting the ecology and economy of the Segara Anakan region, a mangrove-fringed lagoon in central Java, Indonesia. The lagoon’s increasing sedimentation/silting up and the area’s expanding population has led to various interest groups conflicting with one another over how the resources of the lagoon and its surrounding area are to be utilized. Conflicts arise between occupational and ethnic groups in the lagoon’s bordering villages in the context of a transformation from fisheries to wetland agriculture. Land and mangrove use is therefore a cause for conflict between multiple groups, including Javanese fishermen, Sundanese farmers from Central and West Java and external shrimp farm owners. A result of the “Segara Anakan Development Project”—an 8-year undertaking that began in 1996—is that the lagoon was frequently dredged. Due to the dredging and resulting contamination of the land, a regional clash was triggered between Sundanese farmers and Javanese fishers. Our study reveals that the conflict potential between the various interest groups in the Segara Anakan Lagoon area could be reduced if the scarcity of natural resources were alleviated. Religious aspects also play a large role in marine resource utilization. Recognizing that the human utilization of natural resources is strongly symbolic and thereby culturally defined, we unravel the resource conflicts in our study area and offer some strategic approaches towards more sustainable outcomes.     

Estimating willingness to pay with the stochastic payment card design: further evidence from rural Cameroon

This study reports new empirical findings of the field test of the stochastic payment card (SPC) design recently proposed by Wang (Contingent valuation of environmental resources: A stochastic perspective, 1997a; Journal of Environmental Economics & Management 32:219–232, 1997b). The purpose is to see how well this new contingent valuation method (CVM) elicitation format works in different cultural contexts, and what lessons can be drawn in general regarding its usefulness in environmental valuation. The survey is designed to estimate willingness to pay (WTP) values for an intended community-based environmental project in rural Cameroon (i.e., the control of malaria using larvivorous eating fish species). In order to estimate the bid function, Heckman’s 2-step method is used to detect, and if possible, correct for sample selection bias, an issue overlooked by the 2-step modeling approach proposed by Wang (1997a). The results suggest generally that in the presence of sample selection bias, Heckman’s 2-step estimates are more efficient and reliable for the public project in question than Wang’s proposed 2-stage modeling approach.     

复合垂直流构建湿地净化污水机制研究 Ⅰ微生物类群和基质酶

构建湿地是 2 0世纪 70年代才蓬勃兴起的一种处理污水的方式 ,由于其造价和运行费用低 ,净化效果稳定 ,越来越引起各国的兴趣和高度重视。现已广泛应用于城市生活污水、工业污水和农业污水的控制 ,有着十分广阔的应用前景。虽然关于构建湿地净化污水的研究已有不少报道 ,但关于湿地基质中的微生物类群和基质酶在污水净化中的作用仍不清楚。通过对生长在复合垂直流构建湿地和天然环境条件下菰和石菖蒲根区微生物类群数量及其根区基质酶活性的测定发现 :同种植物在复合垂直流构建湿地根区微生物的数量比天然条件下的要高 ,特别是硝化细菌和反硝化细菌的数量 ,最高可达 3个数量级以上 ;同时复合垂直流构建湿地中不同植物根区的酶活性有较大差别 ,这为研究复合垂直流构建湿地净化污水的机理和以酶活性强弱作为净化效果的评价指标提供了科学资料 ,为进一步研究提供了一条新思路     

北京奥林匹克森林公园人工湿地生态系统服务非使用价值的评估

介绍了北京奥林匹克森林公园人工湿地的基本概况,论述了该生态系统所具有的服务功能,指出对其美学欣赏、休闲娱乐和科研教育等非使用价值进行评估的重要意义。采用意愿调查评价法(Contingent Valuation Method,CVM)评估了其非使用价值。通过问卷设计、预调查、正式调查、问卷分析,得出支付意愿均值为16023元/（户〖DK1〗·年）;通过进入法(Enter Regression)、逐步分析法(Stepwise Regression)以及部分变量对数化后的逐步分析法等3种多元线性回归分析方式,探讨了支付意愿与受访者社会经济变量的关系,得出最优的回归模型证明对人工湿地越了解、家庭年收入越高以及受教育年限越长的受访者支付意愿就越高。最后,通过选择合理的背景人数,得出在未来20 a内北京奥林匹克森林公园人工湿地的平均总支付意愿为 12336.56 万元/年,总净现值为 189042.97、161427.85 和 139842.25 万元(折现率分别为3%、5%和7%)。〖     

Women NGOs and rural women empowerment activities in the Niger Delta, Nigeria

The study attempted to document beneficiaries’ perceptions on the contributions of Women NGOs (WNGOs) to the socio-economic empowerment of rural women in Akwa Ibom State, Nigeria. The specific objectives of the study included: an assessment of WNGOs contributions to improvements’ in beneficiaries’ socio-economic activities and constraints affecting beneficiaries’ participation in WNGOs activities. An attempt was also made to determine the existence of a significant relationship between the pre and post-participation income of WNGOs beneficiaries. A sample size of 240 respondents from 48 Local Women Groups (LWGs), which are affiliated to three active WNGOs in four states of the Niger Delta were utilized for the study. Findings revealed that WNGOs cater for a broad spectrum of rural women. WNGOs were revealed to affect beneficiaries’ socio-economic statuses through increased income generation, health awareness and acquisition of food processing skills. Constraints affecting beneficiaries’ participation in WNGOs activities include: inadequate credit facilities, and poor utilization of credit advances, resulting in poor loan repayment levels. A direct relationship was also revealed to exist between increased beneficiary exposures to WNGOs credit facilities and increased beneficiary income. It is believed that WNGOs are capable of more effective inputs into human and community development activities. Recommendations are proffered in this respect. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.     

Selection of (bio) indicators to assess effects of freshwater use in wetlands: a case study of s’Albufera de Mallorca, Spain

Parc Natural sAlbufera de Mallorca is an internationally recognised resting area for a wide array of migratory birds, and like most wetlands it has many other ecological functions and socio-economic values. In the catchment, in which the wetland is situated, expanding tourism and intensification of agriculture place much pressure on a limited amount of freshwater. The freshwater supply to the wetland decreased due to water-extraction mainly driven by intensification of agriculture in the catchment. As a result saltwater intrusion increased since 1983–1985. This had considerable impacts on the ecological integrity of the wetland as reflected by changes in the state of the aquatic ecosystem. The distribution of submerged plants, less tolerant of salinity, declined or disappeared, while the distribution of species, known to prefer high salinity increased. As a contribution to the development of monitoring programs and management strategies that address both socio-economic and natural water demand, this article will formulate ecological criteria to assess the natural water demand by selection of (bio)indicators within the aquatic ecosystem.     

水量衡算条件下人工湿地对有机物的去除

构建了芦苇和无植物人工湿地,在系统水量衡算的基础上比较了两种湿地对生活污水中有机物的去除效果。结果表明,在植物收割后的冬季,有植物湿地对有机物的去除率低于无植物湿地2.2%;在其他季节,芦苇湿地对污水CODCr的去除率比无植物的高出3.2%～4.2%,但对BOD5的去除率却比无植物的低了1.8%～3.4%。有植物湿地对有机物的去除效果比无植物湿地有所改善,但是提高不多。比较了两种系统的氧化还原电位,有植物湿地比无植物湿地高（P<0.05）,这种提高主要集中在湿地水面以下约15 cm的范围,从整体来看,两块湿地内部氧化还原状态大体相同,主要是强还原环境。比较了两块湿地基质中降解有机物的细菌、放线菌和真菌的数量,二者没有明显的差别,但是,有植物湿地的根际效应明显。考察了湿地进水有机负荷与去除量的关系,二者呈现显著的线性相关性(R2>0.96)。      

人工湿地系统去除藻毒素研究

以含水华的鱼塘水作为进水灌溉两套上行流－下行流人工湿地系统,系统内种植芦苇等水生植物。灌溉一周后收集人工湿地进出水水样,用ＨＰＬＣ法检测其藻毒素定量,结合温度、电位、溶氧等理化指标和细菌、藻类数量的变化,分析人工湿地系统对藻毒素的去除效果及影响其效果的可能因素。结果表明,人工湿地系统对藻毒素有一定的去除效果优于茭白－石菖蒲组合的湿地系统。在三种主要藻毒素ＲＲ、ＹＲ、ＬＲ中,湿地对ＹＲ的去除效果最好     

湖北省湿地的保护与利用

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