摘要
为定量探究"红裸土"景观形成与土壤侵蚀之间的联系,笔者采用137Cs示踪法,分析了同一坡度3种不同覆被条件下土壤137Cs变化特征。结果表明:该区域的137Cs背景值为878.41 Bq/m2;137Cs在山原红壤剖面中的分布深度较浅,通常在15 cm以内;经测算,云南松林覆被下的土壤侵蚀速率为1252.34 t/(km2·a),草丛覆被下的土壤侵蚀速率为3069.718 t/(km2·a),"红裸土"中未能测到137Cs,土壤侵蚀速率呈现出"红裸土">草丛>松林的侵蚀趋势。山原红壤覆被条件劣化是导致土壤侵蚀速率增大的重要原因,土壤侵蚀是"红裸土"景观形成的重要因素,植被保育是控制"红裸土"景观形成的关键。
In order to study the connection between landscape formation of ＂red-bare, soil＂ and soil erosion, ~37Cs change features of 3 different cover conditions under the same gradient were anal^yzed by the method of ~37Cs trace. The results showed that： the background value of 137Cs was 878.41 Bq/m^2; the distribution of ^137Cs in the profile of mountain-bare-soil was relatively shallow, which was within 15 cm usually. The soil erosion rate under the Yunnan pine forest land-cover was 1252.34 t/（km^2·a） and it was 3069.718 t/（km^2· a） under grass land-cover, the ^137Cs was not detected in the ＂red-bare soil＂. The soil erosion rate followed the tendency of ＂red-bare-soil＂ 〉grass〉pine forest. The worsening condition of mountain red earth land-cover was the fatal factor which contributed to the increase of soil erosion rate, soil erosion was the critical factor to the formation of ＂red-bare-soil＂, and vegetation nursing was the key to control the formation of the ＂red-bare soil＂.
出处
《中国农学通报》
2015年第24期195-198,共4页
Chinese Agricultural Science Bulletin
基金
国家自然科学基金"滇东石漠化地区红裸土景观的形成研究"(41061021)
云南省科技计划专项"基于多学科高技术的云南‘城镇上山’研究与典型示范"(2012CA024)
