地理学报 ›› 2006, Vol. 61 ›› Issue (11): 1181-1188.doi: 10.11821/xb200611007

• 土地利用 • 上一篇    下一篇

不同土地利用方式对岩溶作用的影响——以广西弄拉峰丛洼地岩溶系统为例

章程1,2, 谢运球2, 吕勇2, 蒋勇军1, 曹建华2, 姜光辉2, 杨平恒1, 王冬银1   

  1. 1. 西南大学地理科学学院,重庆 400715;
    2. 中国地质科学院岩溶地质研究所,国土资源部岩溶动力学重点实验室,桂林 541004
  • 收稿日期:2006-05-29 修回日期:2006-09-26 出版日期:2006-11-25 发布日期:2006-11-25
  • 作者简介:章程 (1965-), 男, 浙江诸暨人, 博士, 研究员, 中国地理学会会员。现为西南大学地理科学学院博士后, 主要从事岩溶环境、水文地质与土地利用等方面的研究。 E-mail: chzhang@karst.edu.cn
  • 基金资助:

    中国博士后科学基金 (2005038473); 国家自然科学基金重点项目 (90202016; 40231008); 西南大学自然地理学重点学科基金项目及国土资源部岩溶动力学重点实验室开放基金

Impact of Land-use Patterns upon Karst Processes: Taking Nongla Fengcong Depression Area in Guangxi as an Example

ZHANG Cheng1,2, XIE Yunqiu2, LU Yong2, JIANG Yongjun1, CAO Jianhua2, JIANG Guanghui2, YANG Pingheng1, WANG Dongyin1   

  1. 1. School of Geographic Sciences, Southwest University, Chongqing 400715, China;
    2. Institute of Karst Geology, CAGS; Karst Dynamics Laboratory, MLR, Guilin, Guangxi 541004, China
  • Received:2006-05-29 Revised:2006-09-26 Online:2006-11-25 Published:2006-11-25
  • Supported by:

    China Postdoctoral Science Fund, No.2005038473; Key Project of National Natural Science Foundation of China, No.90202016; No.40231008; The Open Foundation of Physical Geography of Southwest China University and Karst Dynamics Laboratory of Ministry of Land and Resources

摘要:

土地利用可使土壤理化性质产生一系列的变化,从而影响到岩溶作用的方向和强度。以广西马山县弄拉典型峰丛洼地区为例,通过野外溶蚀试片法探讨了不同土地利用方式对岩溶作用的影响。结果表明不同土地利用类型土下溶蚀量存在显著差异。林地与园地土下溶蚀量极大部分大于20 mg/a,明显高于灌丛地及 (休) 耕地 (多小于20 mg/a)。总体上,溶蚀量从大到小依次为园地、林地、耕地、休耕地与灌丛。其中至少有两个主要控制因素:土壤有机质和土壤CO2:林地和园地土下溶蚀作用主要受前者控制,土壤有机质含量越高、pH越低,土下溶蚀量越大。在耕地与灌丛条件下由于土壤有机质含量较低,土下溶蚀量主要受土壤CO2控制。

关键词: 土地利用, 岩溶作用, 溶蚀量, 广西弄拉

Abstract:

Previous study on karst processes was always focused on karstification intensity and its variation under different geological settings, climatic and hydrologic conditions in view of macroscale, or on contribution of carbonate rock weathering to the atmospheric CO2 sink. Lesser attention was paid to impact of land-use types on karst processes. The direction and intensity of karst processes could be deeply affected by soil physical and chemical variations which were resulted from land cover. Taking Nongla Fengcong depression area, Mashan County, Guangxi as an example, the authors discussed the impact of landuse cover on karst processes based on the data of field standard limestone tablet. Almost all the land-use types occurred in a small study area, so the present study is also typical and representative. The results showed that the corrosional ratio at varied soil depth is quite different. Corrosional ratio in woodland and orchard is mostly bigger than 20mg/a, which is much higher than that in cultivated land and shrubs. Generally, corrosional ratio decreased from orchard, woodland, tilled land, fallow and shrubs successively, in which soil organism and soil CO2 are two major controlling factors: corrosion process is controlled remarkably by soil organism in woodland and orchard, the higher the organism content is and the less the pH value is, the higher the corrosional ratio is. Owing to lower organism content, the corrosional ratio affected mainly by soil CO2 in tilled land and shrubs. The impacts of land-use types on karst processes could be active to improve corrosional rate, for example organic fertilization in orchard resulted in soil organic matter increase; or negative to retard corrosional rate, for example surface disturbance in tilled land resulted in soil porosity increase and CO2 emission. Moreover, organism activities and their offspring could be the most active factor, vegetation succession can improve the three-phase condition of karst dynamics system, and thus accelerate the karst processes. Accordingly, the results of this paper have significance of protecting karst fragile soil resources and readjusting land-use structure in Fengcong mountainous area.

Key words: land use, karst processes, corrosional ratio, Nongla, Guangxi