利用2008年和2010年青海省草地生物量野外采样结果,用变差函数探讨地下和地上生物量的空间变异情况,二者存在空间相关性的阈值分别为3720.52和2258.7 5m.结果表明:玛多采样点前后2年地上生物量的变异程度都高于海北;2010年各样地地上生物量变化相对较小.珍秦/巴塘平均地下生物量高于海北地下生物量,玛多平均地下生物量最小；海北和玛多前后2年平均地下生物量年际间变异程度低于珍秦/巴塘样地.对海北、玛多、巴塘和珍秦的地下、地上生物量的误差进行分析,地下生物量和地上生物量误差变异不同.研究不同采样距离对误差的影响发现,随着采样距离的加大,不论地上还是地下生物量,其误差总体呈增加的趋势,但在2500m采样间距下,地下生物量、地上生物量以及二者的比值都出现较为明显的低值.%The mature leaves of 59 Medicago ruthenica species from seven provinces of China were studied using paraffin method. The thickness of upper cuticle, low cuticle, leaves, palisade tissue and spongy tissue, diameter of vascular bundle, palisade tissue/spongy tissue ratio, palisade tissue structure tense ratio and sponge tissue structure loose ratio of leaves were measured by optical microscopy. Anova analysis showed that nine characters were significantly different among different regions (7. 47%~24. 49%). Correlation analysis showed that all indexes had significant correlation. Palisade tissue thickness, sponge tissue thickness, vascular bundle diameter and leaf thickness represented the most variable data. Clustering analysis showed that 59 materials were grouped into six groups and the genetic relationships among populations were related to geographic distribution. Annual precipitation and palisade tissue thickness, sponge tissue thickness and leaf thickness had positive correlation (F<0. 05). Palisade tissue thickness, sponge tissue thickness and leaves thickness were a drought-resistance structure of Medicago ruthenica and related with drought-resistance of Medicago ruthenica.
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