用RS和GIS技术评价福建省长汀县土壤保持功能对生态系统变化的响应

发布时间：2018-02-25 09:54

本文关键词： 生态系统土壤保持功能响应长汀县　出处：《生态学报》2017年01期 　论文类型：期刊论文

【摘要】：人类活动直接影响生态系统的变化,而生态系统变化又改变着其土壤保持功能。通过对生态系统及其土壤保持量变化的对比分析可以发现两者间响应机制,分析水土保持工作的得失,并进而为下一步治理提供指导。基于e Cognition平台利用landsat影像解释出长汀县2000、2010和2016年的生态系统类型,并利用RULSE模型定量评估土壤保持功能,探讨土壤保持量相对于生态系统变化的响应规律。结果表明:2000—2016年间,长汀县生态系统变化主要表现为两大特征:其一是低覆盖类型向高覆盖类型转变,表现为稀疏林大量地转为常绿阔叶林和常绿针叶林,研究期内稀疏林减少14729.38hm~2(减幅56.75%),而常绿阔叶林和常绿针叶林分别增加6791.50hm~2(增幅23.21%)、10228.07hm~2(增幅5.80%);其二是受经济利益驱动,大量耕地和常绿针叶林转为城镇和茶果园,研究期内城镇、茶果园分别增加4469.14hm~2(增幅85.43%)、1949.32hm~2(增幅69.38%)。研究期内全县土壤保持量显著提高,单位面积土壤保持量从2000年217.32t hm~(-2)a~(-1)提高2016年246.02t hm~(-2)a~(-1)。各生态系统中,常绿阔叶灌丛和常绿阔叶林土壤功能最强,单位面积土壤保持量大于277t hm~(-2)a~(-1),而城镇土壤保护功能最弱,单位面积土壤保持量低于65t hm~(-2)a~(-1);研究期内大部分生态系统的土壤保持能力有不同程度提高,只有城镇和茶果园下降,单位面积土壤保持量分别减小21.03t hm~(-2)a~(-1)和16.74t hm~(-2)a~(-1),这说明城镇和茶果园迅速扩张可能引发新的水土流失。从空间上看,土壤保持量提高的区域占全县96.5%,其中东北部森林区和中南部增幅最显著,说明了十几年的水土流失综合治理工作极具成效;另一方面土壤保持量下降的区域散布于人类活动较频繁的各个山间盆谷,其中汀州、大同最为集中,迅速的城镇化与茶果园开发是造成保土功能下降的主要原因。
[Abstract]:Human activities directly affect ecosystem changes, which in turn change the soil conservation function. Through the comparative analysis of the ecosystem and its soil conservation changes, we can find the response mechanism between the two. This paper analyzed the gain and loss of soil and water conservation work, and provided guidance for the next step management. Based on e Cognition platform, the ecosystem types of Changting County in 2010 and 2016 were explained by using landsat images, and the soil conservation function was evaluated quantitatively by RULSE model. The response of soil conservation to ecosystem change was studied. The results showed that the ecosystem changes in Changting County from 2000 to 2016 were mainly characterized by two characteristics: one was the transition from low cover type to high cover type. During the study period, the sparse forest decreased by 14729.38 hmm-2 (by 56.75), while the evergreen broad-leaved forest and evergreen coniferous forest increased by 6791.50 hmm-2 (23.21 ~ 10228.07hm2) (an increase of 5.80hm2) during the study period, and the second was driven by economic benefits. A large number of cultivated land and evergreen coniferous forests were converted into towns and tea orchards. During the study period, the number of tea orchards in towns and towns increased respectively by 4469.14hmm-2 (85.43%) and 1949.32hmm2 (increase rate 69.38%). During the period of study, the amount of soil conservation in the whole county increased significantly. Soil conservation per unit area was increased from 217.32t / hm ~ (-1) to 246.02t / h ~ (-1) on 2016. The soil function of evergreen broadleaved thickets and evergreen broad-leaved forests was the strongest, and the soil conservation per unit area was more than 277t / hm ~ (-1), but the function of urban soil protection was the weakest. The soil conservation capacity per unit area was less than 65t / hm ~ (-1). The soil conservation capacity of most ecosystems increased in varying degrees during the study period, but only decreased in towns and tea orchards. Soil conservation per unit area decreased by 21.03 t / hm ~ (-1) and 16.74 t / h ~ (-1) respectively, indicating that the rapid expansion of towns and tea orchards may lead to new soil erosion. The area where soil conservation increased accounted for 96.5% of the whole county, of which the increase of forest region and central and southern forest region in the northeast was the most significant, which indicated that the comprehensive control work of soil and water loss in more than ten years was very effective. On the other hand, the region of decreasing soil conservation is scattered in various mountain basins and valleys where human activities are more frequent, among which Ting Zhou and Datong are the most concentrated. Rapid urbanization and tea orchard development are the main reasons for the decline of soil conservation function.
【作者单位】：福建师范大学地理科学学院;福建师范大学湿润亚热带山地生态国家重点实验室培育基地;
【基金】：福建省自然科学基金资助项目(2016J01183)
【分类号】：S157;S127

【参考文献】