陆地表层人类活动强度:概念、方法及应用

Human activity intensity of land surface:Concept, method and application in China

人类活动强度是表征人类对陆地表层影响和作用程度的综合指标。在定义陆地表层人类活动强度、建设用地当量等概念的基础上,建立了人类活动强度算法模型和土地利用/覆被类型的建设用地当量系数折算方法,并利用1984-2008年期间6个年份的土地利用数据,对中国进行了实证应用研究。结果表明：中国的人类活动强度变化大致以2000年为界,前期增长相对缓慢,后期增长明显加快,1984年全国的人类活动强度为7.63%,到2008年上升为8.54%。2008年县级单元的人类活动强度按大于27%、16%～27%、10%～16%、6%～10%和小于6%划分为高、较高、中等、较低和低5个等级,其空间分布格局大致以贺兰山—龙门山—景洪线为界分为东、西两个部分。东部是高、较高和中等类型的集中分布区,低和较低类型呈条带状分布于山地、丘陵区;西部以低和较低类型为主体,在甘肃河西走廊、青海东部及新疆天山南北坡有零散的中等和较高类型分布。

Human activity intensity is a synthesis index for describing the effect and influence of land surface. This paper presents the concepts of human activity intensity and construction land equivalent, builds an algorithm model for human activity intensity, and establishes a method for converting different land use/land cover types into construction land equivalent as well. An application in China based on the land use data from 1984 to 2008 is also included.The results are shown as follows：（1） Human activity intensity is defined as the degree of land use, transformation and exploitation by human beings. It is an effective way to determine the construction land equivalent coefficient of different land use/land cover types by taking construction land equivalent as a basic unit and identifying the alteration of land surface natural properties caused by human activities. The application in China and correlation analysis with population density indicated that it is feasible to take the ratio of the construction land equivalent area to the total area as an indicator of human activity intensity.（2） We adopted a two-level method of eight attribute labels to construct general standard of converting different land use types into construction land equivalent, and establish a method for calculating the coefficient of construction land equivalent. We also built a coefficient table for constructing land equivalent of 49 land use types based on the latest land use classification system.（3） The human activity intensity in China increased from 7.63% in 1984 to 8.54% in 2008. It could be generally divided into five levels： very high, high, medium, low and very low, according to the human activity intensity at county level in 2008, which is rated by over 27%, 16%-27%, 10%-16%, 6%- 10% and below 6%. The human activity intensity in China was spatially split into eastern and western parts by the line of Helan Mountain- Longmen Mountain- Jinghong; the eastern part was characterized by the levels of very high, high and medium, while the western part was featured by the low and very low levels.