流域地球关键带调查理论方法:以长江中游江汉平原为例

围绕如何运用地球关键带理论解决巨型流域生态环境保护问题，在总结国内外地球关键带研究进展的基础上，结合在长江中游开展的地球关键带调查实践，将流域侵蚀基准面定义为流域地球关键带底边界，建立了流域生态环境问题库、地球四大圈层变量库和人类活动变量库；构建了以典型生态环境问题为导向的、基于地球系统四大圈层、人类活动和时间的六维环境变量矩阵；提出了流域地球关键带横向三断面和垂向五界面的结构概化模型，识别了各断面和界面的共性变量和特征变量.有效突破了传统地球关键带研究局限于小流域、环境变量梯度和生态环境问题相对单一的不足，科学回答了流域地球关键带“在哪里调查”、“调查什么”和“监测什么”的问题，初步构建了流域地球关键带调查理论方法体系，并在江汉平原进行了示范性研究.本文为长江流域地球关键带调查以及长江大保护战略的实施提供了科学依据，并为我国流域地球关键带调查理论方法体系的建立提供探索性经验. 

Theoretical Approaches of Survey on Earth's Critical Zone in Basin: An Example from Jianghan Plain,Central Yangtze River

Around how to use the theories of Earth's Critical Zone (CZ) to resolve ecological environment protection problem of large basin, it defines the base level of erosion for basin as the bottom boundary of CZ in basin, based on the domestic and foreign research progress on CZ in combination with survey on CZ in central Yangtze River basin. It conducted the ecological environment problem library of basin, the variable library of four spheres for earth and the variable library of anthropogenic activities. Based on "four spheres for earth", "anthropogenic activities" and "time", it also constructed the six-dimensional matrix guided by typical ecological environment problems. It proposes that three horizontal-sections and five vertical-interfaces as structural model of CZ in basin, and also identify the common/feature variables of sections and interfaces. According to the above results, we establish preliminary theoretical approaches of survey on CZ in basin and conduct an exemplary research in Jianghan Plain, which breaks through traditional CZ research limitation due to relatively single study on small watershed, gradient of environmental variable and ecological environment problems. We also answer the question on "where to survey", "what to survey" and "what to monitor" of CZ in basin. This study provides a scientific basis for survey of CZ in Yangtze River basin and implementation of Yangtze River protection, and exploratory experiences for the establishment of theoretical approaches of survey on CZ in basin.