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对近１０年来国内有关落叶松人工林地力衰退问题的研究结果表明：落叶松人工林对土壤性质有不良影响，具体表现为土壤密度、孔隙度、结构、持水量、酸度、有机质含量、养分元素（Ｎ、Ｐ、Ｋ、Ｃａ、Ｍｇ等）含量及有效性、土壤微生物数量及酶活性等一系列肥力指标质量的下降和某些条件下第二代落叶松人工林生产力的衰退。从人工林生态系统的多样性和稳定性、落叶松人工林养分循环特点、落叶松凋落物对土壤性质的影响及营林生产活动的干扰等多方面分析了地力衰退的原因。最后，对调整群落结构、合理轮作、林地施肥及土壤改良等一系列防止落叶松人工林地力衰退的对策和措施进行了总结和评价
The results of the study on the decline of the soil fertility of larch plantations in the past 10 years show that larch plantations have adverse effects on the soil properties, including soil density, porosity, structure, water holding capacity, acidity, organic matter content, (N, P, K, Ca, Mg, etc.) and the decline of the productivity of second-generation larch plantation under certain conditions. The reasons for the decline of soil fertility were analyzed from the diversity and stability of plantation ecosystem, the nutrient cycling characteristics of larch plantation, the impact of larch litter on soil properties and the disturbance of forest production activities. Finally, a series of measures and measures to prevent the decline of soil fertility of larch plantation were summarized, such as adjusting the community structure, rational rotation, fertilization of forestland and soil improvement