【摘 要】
：
杜尔伯特蒙古族自治县是松嫩沙地沙漠化面积最大的县，他拉哈镇是该县沙漠化比较有代表性的地区。土地沙漠化分布在全镇各村屯，面积为109.91km2，占全镇土地总面积22.95％，主要为轻度和中度沙漠化类型。在沙地的沙丘中普遍发育1～2层古土壤层，经(14)C测年为(4197±383)a BP～(7463±143)aBP。经孢粉分析，草本植物花粉较多，乔、灌木植物花粉较少，古土壤层属全新世大暖期时期形成
【机 构】
：
中国科学院 东北地理与农业生态研究所，吉林 长春 130012 黑龙江省杜尔伯特蒙古族自治县林业局
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杜尔伯特蒙古族自治县是松嫩沙地沙漠化面积最大的县，他拉哈镇是该县沙漠化比较有代表性的地区。土地沙漠化分布在全镇各村屯，面积为109.91km2，占全镇土地总面积22.95％，主要为轻度和中度沙漠化类型。在沙地的沙丘中普遍发育1～2层古土壤层，经(14)C测年为(4197±383)a BP～(7463±143)aBP。经孢粉分析，草本植物花粉较多，乔、灌木植物花粉较少，古土壤层属全新世大暖期时期形成。沙地沙漠化的成因，既有自然因素又有人为原因。对中度沙漠化土地(包括沙丘地)一般采取疏林、灌、草治理模式；对轻度沙漠化土地(含沙平地)采取林、果、药(草)、杂(小杂粮)治理模式。
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