中文摘要：

滋养的再吞是重要保存机制让植物在 desertified 土地的不太肥沃的区域克服滋养的限制。在北中国的半干旱的 Horqin 沙的陆地，灌木 Artemisia halodendron 通常开拓殖民地于进赤裸的地面严重地 desertified 土地作为先驱种。因此，它被期望那 A。halodendron 将不太依赖于通过营养素的有效、熟练的再吞的当前的滋养的举起。在这研究，我们在分别地，显著地在固定的沙沙丘在变的沙沙丘从 12.3 和 1.2 mg/g 改变到 15.9 和 1.9 mg/g 的开始衰老的叶子发现了那平均氮(N) 和磷(P) 集中建议 A 的那叶的 N 和 P 再吞。halodendron 在变的沙沙丘是更熟练的。特别地，在在开始衰老的叶子和土壤营养素可获得性的滋养的集中之间的积极关系显示那 A。在不肥沃的产地的 halodendron 是更可能的在开始衰老的叶子与营养素的底层设法，给这种在不肥沃的土壤的一个优点。而且，尽管年度降水在 20072009 之中极大地变化了，显示出的叶的 N 再吞和 P 再吞效率和熟练限制了内部年度的可变性。然而， A 的 N 和 P 再吞。halodendron 不比以前为另外的灌木报导的那些更有效、熟练，显示在沙沙丘环境的先驱灌木不比保存营养素的再吞的过程上的另外的植物更重重地依靠。在 A 的营养素的不完全的再吞。halodendron 建议开始衰老叶的秋天将与高质量把垃圾还给土壤，并且将间接地从而改进土壤营养素可获得性。因此， desertified 土地的恢复可以在 A 以后被加速。halodendron 先驱进转移沙沙丘。

英文摘要：

Nutrient resorption is an important conservation mechanism for plants to overcome nutrient limitation in the less fertile area of desertifled land. In the semi-arid Horqin Sandy Land of Northern China, the shrub Artemisia ha/odendron usually colonizes into the bare ground of severely desertified land as a pioneer species. It is, therefore, expected that A. ha/odendron will be less dependent on current nutrient uptake through efficient and proficient re- sorption of nutrients. In this study, we found that averaged nitrogen （N） and phosphorus （P） concentrations in se- nesced leaves significantly varied from 12.3 and 1.2 mg/g in the shifting sand dune to 15.9 and 1.9 mg/g in the fixed sand dune, respectively, suggesting that foliar N and P resorption of A. ha/odendron were more proficient in the shifting sand dune. In particular, positive relationships between nutrient concentrations in senesced leaves and soil nutrient availability indicate that A. ha/odendron in infertile habitats is more likely to manage with a low level of nu- trients in senesced leaves, giving this species an advantage in infertile soil. Moreover, foliar N- and P-resorption efficiencies and proficiencies showed limited inter-annual variability although annual precipitation varied greatly among 2007-2009. However, N and P resorption of A. ha/oc/endron were not more efficient and proficient than those previously reported for other shrubs, indicating that the pioneer shrub in sand dune environments does not rely more heavily than other plants on the process of resorption to conserve nutrients. Incomplete resorption of nutrients in A. halodendron suggests that senesced-leaf fall would return litter with high quality to the soil, and thereby would indirectly improve soil nutrient availability. The restoration of desertified land, therefore, may be ac- celerated after A. halodendron pioneers into shifting sand dunes.