摘要
对呼伦贝尔沙质草原187个现代风蚀坑野外调查获得的形态指标、发展阶段、诱发原因、现代放牧压力进行了对比分析。发现87%的风蚀坑由人类活动引起。其中翻耕、道路、人类定居活动诱发的风蚀坑分别占35.8%、34.8%和16%。人类定居活动诱发的风蚀坑分布范围最广。翻耕诱发的风蚀坑有97%处于活动状态。翻耕造成的土壤损失对生态地质环境破坏严重且影响深远。放牧既能促使固定风蚀坑活化并助长风沙活动,也能促进风蚀坑加速消亡。合理确定放牧压力很重要。翻耕造成的面状土层破坏诱发大量风蚀裸地和规模巨大的短轴型风蚀坑。道路切割土层诱发受道路延伸方向控制串状分布的长轴型风蚀坑。呼伦贝尔沙质草原正面临新一轮沙漠化的严重威胁。保护沙质草原区植被和地表土层不受破坏是防止风蚀坑发生发展的关键。促进土层以及草原植被的形成与恢复是风蚀坑控制的根本途径。
The shapes, development stages, and formation causes of 187 modern blowouts in HulunBuir Sandy Grassland were compared on the background of different grazing and human activity pressures. It was discovered that 87 % of blowouts are caused by human activities, with plowing, grassland motor vehicle natural road, and resident related activities counting for 35.8%, 34.8%, and 16% respectively. Blowouts caused by resident related activities have the widest spread. And 97% of the plowing-caused bare soil and blowouts are in active development, indicating destruction to soil layer structure and material loss brought forth by plowing is serious and has long aftereffect. Herding can bring fixed blowouts back to active along their edges and at dunes, as well as to facilitate blowouts＇ process of level off and revegetation. What is important is to set herding pressure or quota in a reasonable scale. With regard to morphological change of blowouts in relation to causes, large scale destruction of top soil layer by plowing results in wide spread bare soil and large round blowouts, whereas motor vehicle natural roads results in string lined elongated blowouts when the ruts mill and cut through top soil layer. HulunBuir Grassland is endangered by a new phase of sandy de： sertification. Protection of grassland vegetation and top soil layer is vital to avoiding the development of blowouts. Facilitate the resumption of soil layer formation and revegetation is the fundamental way to control blowouts.
出处
《中国沙漠》
CSCD
北大核心
2007年第2期214-220,共7页
Journal of Desert Research
基金
国家自然科学基金项目(40471013)
内蒙古自治区自然科学基金项目(200308020512)
呼伦贝尔市农业攻关与社会发展项目(2002-01-15)共同资助
关键词
风蚀坑
成因
形态变化
沙漠化
风沙地貌
地表土层
呼伦贝尔沙质草原
blowout
cause of formation
morphological change
sandy desertification
aeolian geomorphology
top soil layer
HulunBuir Sandy Grassland
