沙地衬膜水稻田休耕对土壤氮磷钾库容的影响
Effects of Fallow on Soil Nitrogen, Phosphorus and Potassium Storage Capacity in Sandy Paddy Field Lined with Film

探究科尔沁沙地连续种植衬膜水稻与种稻后休耕对土壤氮磷钾库的影响，为荒漠化治理提供科学依据。以研究区未修复沙地为对照，测定连续种稻和种稻后休耕0~15和15~30 cm土层土壤全氮、全磷、全钾、速效氮、有效磷和有效钾含量，同时分析休耕土壤氮磷钾库容与环境因子的相关性。结果表明：种稻和休耕对土壤氮磷钾库组分含量影响显著，土壤全氮含量以及C/N总体呈先显著升高后显著下降的变化趋势，大小差异顺序均为：稻田 > 休耕地 > 沙地。种稻后土壤硝态氮和有效钾含量以及速效氮、有效磷和有效钾分配比例较种稻前显著下降，休耕前后无明显变化规律。不同处理间土壤全磷、全钾、铵态氮、速效氮和有效磷含量差异不显著。休耕后土壤氮磷钾库间存在显著正相关关系，休耕土壤氮磷钾库容与C/N和含水量存在极显著正相关关系，C/N和含水量可作为表征休耕地土壤养分变化的敏感指标。
In order to provide scientific basis for desertification control, soil nitrogen, phosphorus and po-tassium pools affected by continuous planting of film lined rice and fallow after planting film lined rice need to be studied in Horqin. Taking the unrepaired sandy land in the study area as the control, the contents of soil total nitrogen, total phosphorus, total potassium, available nitrogen, available phosphorus and available potassium in 0~15 and 15~30 cm soil layers after continuous rice planting and rice planting were measured, and the correlation between nitrogen, phosphorus and potassium storage capacity of fallow soil and environmental factors was analyzed. The results showed that planting rice and fallow had a significant effect on the content of soil nitrogen, phosphorus and potassium pool. The content of soil total nitrogen and C/N increased significantly at first and then decreased significantly. The order of difference was: paddy field > fallow farmland > sandy land. After planting rice, the content of soil nitrate nitrogen and available potassium and the distribution proportion of available nitrogen, available phosphorus and available potassium decreased significantly compared with that before planting rice, and there was no obvious change law before and after fallow. There was no significant difference in the contents of total phosphorus, total potassium, ammonium nitrogen, available nitrogen and available phosphorus among different treatments. After fallow, there is a significant positive correlation between soil nitrogen, phosphorus and potassium pools. There is a very significant positive correlation between fallow soil nitrogen, phosphorus and potassium pool capacity and C/N and water content. C/N and water content can be used as sensitive indicators to characterize the changes of soil nutrients in fallow.