湿地序列监测图像的地物目标分类方法

针对固定观测站采集的序列图像中光照变化和背景复杂的问题,将图像序列作为图像在时间维的拓展,提出一种结合颜色空间变换和神经网络的目标分类方法,以辽河口湿地为例开展实地观测试验。基于前期现场调查得到的地物分布信息,将序列图像转换至HSV空间,选择像素小区域作为样本训练多层神经网络,获得更高维度分类依据映射,并完成潮滩生态监测区域目标分类及重要湿地植物翅碱蓬的分布信息提取。对提取结果进行定量验证,该方法整体精确率稳定在90%左右。     

我国湿地保护的存在问题及法律对策

湿地是重要的自然资源之一,保护湿地对于生态环境有着极其重要的作用,然而湿地的法律保护在我国却是一个薄弱环节。本文论述了我国湿地保护中存在的若干问题,并提出具体的法律对策——制定《湿地保护法》。     

全域旅游视角下的扎龙湿地自然保护区生态旅游发展研究

扎龙湿地作为国家级自然保护区,旅游资源丰富,具有发展生态旅游的物质基础.以全域旅游作为视角,通过营造全域旅游发展格局、整合湿地旅游资源、降低生态负面损失以及打造生态旅游新品牌等方面,分析扎龙湿地自然保护区的旅游环境,针对生态旅游提出发展思路.     

Prioritizing Wetland Restoration for Sediment Yield Reduction: A Conceptual Model

In a climate of limited resources, it is often necessary to prioritize restoration efforts geographically. The synoptic approach is an ecologically based tool for geographic prioritization of wetland protection and restoration efforts. The approach was specifically designed to incorporate best professional judgment in cases where information and resources are otherwise limited. Synoptic assessments calculate indices for functional criteria in subunits (watersheds, counties, etc.) of a region and then rank the subunits. Ranks can be visualized in region-scale maps which enable managers to identify areas where efforts optimize functional performance on a regional scale. In this paper, we develop a conceptual model for prioritizing watersheds whose wetlands can be restored to reduce total sediment yield at the watershed outlet. The conceptual model is designed to rank watersheds but not individual wetlands within a watershed. The synoptic approach is valid for applying the sediment yield reduction model because there is high demand for prioritizing disturbed wetlands for restoration, but there is limited, quantitative, accurate information available with which to make decisions. Furthermore, the cost of creating a comprehensive database is prohibitively high. Finally, because the model will be used for planning purposes, and, specifically, for prioritizing based on multiple decisions rather than optimizing a single decision, the consequence of prioritization errors is low. Model results cannot be treated as scientific findings. The conclusions of an assessment are based on judgement, but this judgement is guided by scientific principles and a general understanding of relevant ecological processes. The conceptual model was developed as the first step towards prioritizing of wetland restoration for sediment yield reduction in US EPA Region 4.     

中国湿地现状综述

湿地是重要的自然资源,对人类生存起着重要作用。本文综述了湿地的含义、功能与 价值、中国湿地的特点与现状,以促进中国湿地的可持续发展与利用。     

Bird Use of Restoration and Reference Marshes Within the Barn Island Wildlife Management Area, Stonington, Connecticut, USA

/ Tidal marshes have been actively restored in Connecticut for nearly 20 years, but evaluations of these projects are typically based solely on observations of vegetation change. A formerly impounded valley marsh at the Barn Island Wildlife Management Area is a notable exception; previous research at this site has also included assessments of primary productivity, macroinvertebrates, and use by fishes. To determine the effects of marsh restoration on higher trophic levels, we monitored bird use at five sites within the Barn Island complex, including both restoration and reference marshes. Use by summer bird populations within fixed plots was monitored over two years at all sites. Our principal focus was Impoundment One, a previously impounded valley marsh reopened to full tidal exchange in 1982. This restoration site supported a greater abundance of wetland birds than our other sites, indicating that it is at least equivalent to reference marshes within the same system for this ecological function. Moreover, the species richness of birds and their frequency of occurrence at Impoundment One was greater than at 11 other estuarine marshes in southeastern Connecticut surveyed in a related investigation. A second marsh, under restoration for approximately ten years, appears to be developing in a similar fashion. These results complement previous studies on vegetation, macroinvertebrates, and fish use in this system to show that, over time, the reintroduction of tidal flooding can effectively restore important ecological functions to previously impounded tidal marshes.KEY WORDS: Estuarine; Tidal marsh; Wetland birds; Restoration     

Changes in wetlands on nonfederal rural land of the conterminous United States from 1982 to 1987

Recent wetland area trends were estimated from the National Resources Inventory (NRI) for nonfederal rural lands for the period 1982–1987. NRI-based estimates of wetland area for states comprising the conterminous United States were highly correlated with estimates made by the US Fish and Wildlife Service and with estimates of coastal salt marsh wetlands made by the National Oceanic and Atmospheric Administration. Net wetland area declined by 1.1% (≈363,200 ha) during the five-year study period. Conversion to open water, primarily caused by natural flooding in western inland basins, was responsible for altering extensive wetland areas (≈171,400 ha). Of the human-induced wetland conversions, urban and built-up land was responsible for 48% of the wetland loss, while agricultural development was indicated in 37% of the converted wetland area. A decrease in rural land, and increases in both population, and urban and built-up land were associated with wetland loss among states. Potential reasons for wetland loss were different in 20 coastal states than in 28 inland states. Proportionately, wetland loss due to development was three times greater in coastal states than inland states, while agriculturally induced wetland losses were similar in both groups. The proportionate declines of forested vs nonforested wetlands were not significantly different among states.     

上海地区湿地生态旅游资源研究

从国内外湿地研究进展中发现,湿地景观资源及其管理对策研究得到人们越来越广泛的重视。上海市湿地面积广阔,占全市海拔-5m以上总面积9123km^2的65．67％,同时具有景观多样性和生物物种多样性。丰富的湿地资源为上海市提供了广阔的绿地空间,成为宝贵的旅游资源。本文对上海市的湿地景观资源进行了细致的分析,并介绍了其开发和利用现状,在此基础上提出了规划设想和几点建议。     

Use of Microbial Community to Evaluate Performance of a Wetland System in Treating Pb/Zn Mine Drainage

The performance of a wetland system in treating lead (Pb)/zinc (Zn) mine drainage was evaluated by using the polyurethane foam unit (PFU) microbial community (method), which has been adopted by China as a standardized procedure for monitoring water quality. The wetland system consisted of four cells with three dominant plants: Typha latifolia, Phragmites australis and Paspalum distichum. Physicochemical characteristics [pH, EC, content of total suspended solid (TSS) and metals (Pb, Zn, Cd, and Cu)] and PFU microbial community in water samples had been investigated from seven sampling sites. The results indicated that the concentrations of Pb, Zn, Cd, Cu, and TSS in the mine drainage were gradually reduced from the inlet to the outlet of the wetland system and 99%, 98%, 75%, 83%, and 68% of these metals and TSS respectively, had been reduced in concentration after the drainage passed through the wetland system. A total of 105 protozoan species were identified, the number of protozoa species and the diversity index (DI) gradually increased, while the heterotrophic index (HI) gradually decreased from the inlet to the outlet of the wetland system. The results indicated that DI, HI, and total number species of protozoa could be used as biological indicators indicating the improvement of water quality.     

The role of remote sensing in hydrological modelling of the Okavango Delta, Botswana

A coupled surface water-groundwater model of the Okavango Delta has been built based on the United States Geological Survey software MODFLOW 2000 including the SFR2 package for stream-flow routing. It will provide a new tool for evaluating water management and climate change scenarios. The delta's size and limited accessibility make direct, on the ground data acquisition difficult. Remote sensing methods are the most promising source of acquiring spatially distributed data for both model input parameters and calibration. Topography, aquifer thickness, channel positions, evapotranspiration and precipitation data are all based on remote sensing. Simulated flooding patterns are compared to patterns derived from visible to thermal NOAA-AVHRR data and microwave radar ENVISAT-ASAR data.