沙化土地光谱数据源分为单一地物类型级和复合地物类型级两种，野外测量时分别采取不同的采样方法。

Spectral data sources of sandy land included single surface feature and composite surface feature, and their spectral data were measured by different sampling methods.

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并论述了人骨测年的方法以及在野外采样的注意事项。

The authors have adopted several means to date the human bone with the aim of improving the accuracy.

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采用野外采样及室内分析方法，研究了剑湖自然保护区湿地土壤特性，探讨了农业利用和人为活动干扰对剑湖湿地土壤的影响以及森林对湿地的涵养作用。

We analyzed the impacts of agricultural activities, forest vegetation and human disturbances on wetland soil by studying on the soil characteristics of Jianhu nature reserve wetland.

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