科尔沁沙地榆树疏林草原植被研究

榆树疏林草原是温带典型草原地带、适应半干旱半湿润气候的隐域性沙地顶级植物群落 ,广泛分布于科尔沁沙地、浑善达克沙地 ,是防风固沙、保护沙区生态环境和周边土地资源的一种重要的植物群落类型 ,也是耐旱沙生植物的重要物种基因库和草原野生动物的重要避难所和栖息地。然而 ,由于人类的干扰 (如毁林开荒、过度放牧、甚至片面地建立人工林群落等 ) ,不同程度地破坏了榆树疏林的生态环境 ,影响了其特有的生态作用。遥感监测结果表明 ,分布在科尔沁沙地的榆树疏林草原总面积仅有 41 .4万 hm2 ,通常由乔木、草本或乔木、灌木、草本二个或三个层次构成 ,按疏林群落组成可分为白榆疏林草原、白榆疏林灌丛草原、大果榆疏林草原、大果榆疏林灌丛草原、白榆 +大果榆疏林草原和白榆 +大果榆疏林灌丛草原六种类型。榆树疏林草原的类型多样 ,结构复杂 ,具有多种经营利用方向 ,按照经营利用方向 ,可以划分为以下三种 : 型散生的榆树疏林草原 ,榆树稀疏地散生于沙地草原上 ,有效地保护着牧草的生长 ,同时也可以为放牧牲畜提供良好的庇护 ,属于放牧型疏林草地 ; 型团块状的榆树疏林草原 ,榆树多呈团块状分布 ,少则 3～ 5株 ,多则 1 0～ 2 0株构成一个团块 ,团块内榆树生长相对通直 ,可以成材利用 ,这种类型的草地具?

Studies on Elm Woodland Steppe in Kerqin Sandy Land

Elm woodland steppe is a peak vegetable community that adapted to semi-arid and semi-humid climate in typical steppe region, and distributed widely in Kerqin sandy land, Hunshandake sandy land. It is an important vegetable community type for wind prevention , sand fixing and ecological environment protection of sandy land. But ,the disturbances from human destroyed the ecological environment of elm woodland steppe seriously and influenced its special ecological function. The result of remote sensing monitor showed: the total area of elm woodland steppe distributed Kerqin sandy land is only 0.414 million hm2, generally made of arbor and grass or arbor\, shrub and grass. It can be divided Ulmus pumila L. woodland steppe; Ulmus pumila L-shrub woodland steppe; Ulmus macrocarpa Hance. woodland Steppe; Ulmus macrocarpa Hance-shrub woodland steppe; Ulmus pumila L.+ ulmus macrocarpa Hance. woodland steppe and Ulmus pumila L.+ Ulmus macrocarpa Hance.+ shrub woodland steppe etc 6 types according to the component of woodland. Elm woodland steppe having diverse types, complicate structure and multi-management and utilization types. So, enclosure recovery or artificial re-establishent of elm woodland steppe can get great ecological and economical benefit.