摘要
云南横断山区以其生物多样性丰富著称，又是一个有国际兴趣的生态敏感区。然而，它也不乏生态忧患。乡村景观的实地考察说明：这些地区刀耕火种、轮歇耕作仍然盛行，不少居民已经面对着农牧业用地向林区过度扩张所致的水土流失、水源枯竭等严重环境问题。为了解问题之根源，我选择了该山区腹地的８个贫困县，１９９０年开展了人口和农业统计量的相关矩阵分析。结果表明：乡村人口与总人口，耕地面积与总人口、乡村人口，粮食产量和农业总产值呈显著正相关。但在实地考察中发现：人口的持续增量导致地面植被的覆盖率急速下降已成为一种生态警报。
he Hengduan Mountains from Yunnan are well known for their richness in biodiversity, but there is ample concern for these ecologically sensitive areas. From my two field surveys to the hinterlands in 1987 and 1995, respectively, I was shocked by the facts that swidden agriculture still prevailed widely, and some of the villages faced serious soil erosion and water shortages arising from traditional practices. To clarify the problems, a correlation matrix analysis was conducted using published data on total population (PO), villager population (VP), cultivated land area (CLA), grain yield (GY), agriculture output value (AOV) in eight poverty stricken counties in the area in 1990, and their increments between 1985 and 1990. It can be shown that there were significant positive correlations between: a) the VP (90% of PO) and the PO; b)the CLA and the PO, GY, and AOV, respectively; and c) the increment of the CLA and that of the PO and AOV, respectively. Both personal observations and computer outputs give us an ecological warning the natural cover, which remained too little to maintain a healthy ecosystem, would continue to reduce with the growth of population. Better vegetation cover (vs that seen in ordinary circumstances), however, did exist on the slopes behind better farmlands. Accordingly, I believe the social/economic development and the maintenance of biodiversity depend on the success of birth control and the improvement of production model. For the latter, it may be a good choice for development planners to arrange for food production within smaller areas with much improved water and fertility conditions (i.g. through the study and use of agroforestry), and thus to vacate lands for planting economic trees, or allowing vegetation to recover naturally.
出处
《生物多样性》
CAS
CSCD
1996年第4期217-221,共5页
Biodiversity Science
基金
MacArthur基金
关键词
人口
耕地
环境
持续发展
生态信息
correlation matrix, cultivated land, environment, population, sustainable development
