Sustainable Development and Environmental Preservation of Tropical Wetland in the Pantanal, Brazil

主要研究成果如下：1.利用便携式GPS大地测量技术，获得了Baia Bonita农场（1760ha）样区的生境类型分布。2.不同生境类型的形成是由于植物对地形起伏的生态适应和演替以及自然条件的显著差异，河流的入水量、淹没的持续时间、土壤肥力和地下水积累的影响。环境条件基本上建立在河流水位的季节性变化上，最高水位可达2m左右。3.在潘塔纳尔，地下水排放对湿地生态系统非常重要。两个地下水排放系统，即，高HCO_3水型和低HCO_3水型。4.各种严重的环境问题，生态旅游的迅速发展，广泛地造成了野生动物的屠杀、森林的砍伐、水的污染、外来生物的入侵、渔业资源的枯竭。

Principal research results in the period concerned can be summarized as follows.1.The distributions of biotope types in sample area, Fazenda Baia Bonita (1760ha), were obtained from geodetic field survey with potable GPS. As that result, the mosaic distribution of 12 biotope types were identified.2.The formation of the various biotope types is attributed to the ecological adaptations and succession of plants for the landform relief and the remarkable differences of physical conditions, e.g., amount of water inflow from rivers, duration of inundation, soil fertility, and influence of groundwater accumulation. The environmental conditions are basically founded on seasonal changes in the river's water level coming up to some 2m at its maximum.3.In Pantanal, groundwater discharge is quite significant for wetland ecosystem. Two groundwater discharge systems, i.e., high HCO_3 water type and low HCO_3 water type, are identified.4.Various and severe environmental problems, e.g., slaughter of wild animals, deforestation, water pollution, biological invasion from the outside, exhaustion of fishery resource, are widely caused by rapid development of ecotourism.