Doctoral Dissertation Research: Changing the Amazon Landscape: Dynamics of Land Use and Ecological Change in Small Watersheds

博士论文研究：改变亚马逊景观：小流域土地利用动态和生态变化

• 批准号: 0802722
• 负责人: Emilio Moran
• 金额: $ 1.2万
• 依托单位: Indiana University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-07-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0802722&HistoricalAwards=false
• 关键词: Doctoral; Dissertation; Research; Changing; Amazon

Land use changes have dramatically affected the water quality and biological productivity of streams and associated watersheds, particularly within the Brazilian Amazon Basin, where deforestation and extensive agriculture have led to increased surface water flow and nutrient losses from watersheds, including headwater catchments. It is thought that economic and socio-demographic factors have played critical roles in structuring these changes; in particular, household decisionmaking, driven by environmental factors, government policies, and knowledge of land use and water quality are important components driving land and water use choices in small watersheds. These uses have specific outcomes for the water quality found in streams draining small watersheds, particularly the quantity and type of nutrients that are important for the biological productivity of stream ecosystems. As a result, this study evaluates the role of household needs and activities, land and water use, and perception of water quality in affecting the water quality of small watershed streams in an agricultural settlement near Altamira, Brazil. The importance of two kinds of watershed land cover gradients are assessed: amount of forest in a watershed and amount of non-forest in a watershed, as pasture or cacao plantations, which are the two most predominant land uses near Altamira. Examination of water quality and stream water dissolved nutrient concentrations (carbon, nitrogen, phosphorus) at watershed stream outflow points, using standard sampling techniques, provides a summary of the impact of watershed land use on stream water quality. In addition, interviews with small farmers provide information on household structure and knowledge of the relationship between land use and water quality. Remote sensing analyses and a geographic information system are being used to generate information on larger spatial patterns of watershed land use changes. The investigators hypothesize that external market factors, such as prices for agricultural goods, and increasing water needs from agriculture are the predominant factors driving land use and subsequent changes in water quality and stream water dissolved nutrients.The results of this study will provide valuable insights into household land use and environmental change in terrestrial and aquatic ecosystems. In addition, as small streams are widespread in the Amazon Basin and provide important resources for many Amazonian inhabitants, including food and drinking water, the results of this research will provide insights to minimize detrimental impacts on water quality, particularly through understanding how household agricultural land and water use affects the underlying water quality and health of streams. While focused on land use changes in the Brazilian Amazon, this research also addresses land use issues worldwide, as local Amazonian watershed changes ultimately scale-up to affect worldwide ecology, such as global nutrient cycles, and economy, such as agriculture and trade. As a Doctoral Dissertation Research Improvement award, this award also will provide support to foster independent research by a doctoral student.

土地利用的变化极大地影响了河流和相关流域的水质和生物生产力，特别是在巴西亚马逊盆地，砍伐森林和大规模农业导致流域，包括源头集水区的地表水流量和养分流失增加。人们认为，经济和社会人口因素在这些变化的结构中发挥了关键作用；特别是由环境因素、政府政策以及土地利用和水质知识推动的家庭决策，是推动小流域土地和水利用选择的重要组成部分。这些用途对排干小流域的溪流的水质有特定的影响，特别是对溪流生态系统的生物生产力非常重要的营养物质的数量和类型。因此，这项研究评估了家庭需求和活动、土地和水的使用以及对水质的感知在影响巴西阿尔塔米拉附近农业定居点小流域溪流水质方面的作用。评估了两种流域土地覆盖梯度的重要性：流域内的森林数量和流域内的非森林数量，如牧场或可可种植园，这是阿尔塔米拉附近最主要的两种土地利用方式。使用标准采样技术对分水岭溪流流出点的水质和溪水溶解养分浓度(碳、氮、磷)进行检查，总结了分水岭土地利用对溪流水质的影响。此外，与小农户的访谈提供了有关家庭结构的信息和土地利用与水质之间关系的知识。正在利用遥感分析和地理信息系统生成关于流域土地利用变化的更大空间模式的信息。研究人员假设，外部市场因素，如农产品价格，以及农业用水需求的增加，是驱动土地利用以及随后水质和溪水溶解营养物质变化的主要因素。这项研究的结果将为陆地和水生生态系统的家庭土地利用和环境变化提供有价值的见解。此外，由于小河流在亚马逊盆地很普遍，为许多亚马逊居民提供了重要的资源，包括食物和饮用水，这项研究的结果将为最大限度地减少对水质的不利影响提供见解，特别是通过了解家庭农业土地和水的使用如何影响河流的基本水质和健康。虽然这项研究侧重于巴西亚马逊地区的土地利用变化，但也涉及世界各地的土地利用问题，因为当地亚马逊流域的变化最终会扩大规模，影响全球生态，如全球养分循环，以及经济，如农业和贸易。作为博士论文研究改进奖，该奖项还将为培养博士生的独立研究提供支持。