宁夏哈巴湖国家级自然保护区土壤养分5年变化

测定了宁夏哈巴湖国家级自然保护区2013、2018年沙柳（Salix psammophila）群落、油蒿（Artemisia ordosica）群落、锦鸡儿（Caragana microphylla + C. korshinskii）群落和长芒草（Stipa bungeana）群落142个样点的土壤有机质、全氮和全磷含量，分析了土层20 cm处5年间土壤养分的变化。结果表明：从2013年到2018年，整个保护区土壤有机质显著增加52.46%，土壤全氮显著增加154.14%，土壤全磷增加21.75%；油蒿群落57个样点土壤有机质、全氮和全磷含量的增加量高于整个自然保护区，土壤有机质显著增加57.64%，土壤全氮显著增加323.50%，土壤全磷显著增加33.58%。5年来宁夏哈巴湖国家级自然保护区土地沙漠化得到了逆转，同时土壤养分的变化也开始影响植物群落的波动。

Changes of soil nutrients with five years of the Ningxia Habahu National Nature Reserve

In this paper, we determined soil organic matter, total nitrogen and total phosphorus at 20 cm soil layer of Salix psammophila community, Caragana microphylla + C. korshinskii community, Artemisia ordosica community and Stipa bungeana community with 142 sample plots in the Ningxia Habahu National Nature Reserve in 2013 and in 2018, and analyzed the changes of soil nutrients of five years of the whole reserve. The results showed that, from 2013 to 2018, as to the whole reserve, the soil organic matter increased 52.46% significantly, the soil total nitrogen increased 154.14% significantly, and the soil total phosphorus increased 21.75%; as for 57 sample plots of A. ordosica communities, soil organic matter, total nitrogen and total phosphorus significantly increased 57.64%, 323.50%, and 33.58%, respectively. The soil organic matter, total nitrogen and total phosphorus were higher than those of the whole reserve. This illustrated the land desertification of the reserve took place obvious change, meantime, the changes of soil nutrients influenced dynamics of plant community of the Ningxia Habahu National Nature Reserve.