Effects of organic fertilization on the changes of soil nutrient and soil enzyme activities in arid areas | 旱区有机培肥对土壤肥力及酶活性的影响

chinois. 研究不同用量、不同种类有机肥对土壤养分含量和酶活性的影响。在渭北旱塬进行连续2年(2007-2009年)的有机培肥定位试验，以单施化肥处理为对照，研究施用不同量秸秆（9 000，6 000 kg/hm2）和厩肥（22 500，11 250 kg/hm2）后，不同土层（0～20，20～40 cm）土壤养分含量和土壤酶活性的变化。2008年，20～40 cm土层，各有机培肥处理土壤有机质含量较对照增幅为26.87％～33.49%，且差异显著；各有机培肥处理2年的碱解氮和速效磷含量分别在0～40和0～20 cm土层与对照间差异达显著水平；2009年，各有机培肥处理0～20，20～40 cm土层速效钾含量与对照差异均达显著水平，增幅分别为16.86%～35.85%和11.34%～22.61%。有机培肥处理2年，0～40 cm土层的土壤脲酶活性与对照差异均不显著；2009年0～20 cm土层秸秆（9 000，6 000 kg/hm2）和厩肥（22 500 kg/hm2）处理的蔗糖酶活性较对照分别提高了0.19，0.18，0.13 mg/(g•h)，且差异显著；2008年，各有机培肥处理0～20 cm 土层磷酸酶活性与对照的差异均达到显著水平。相关分析表明，磷酸酶、脲酶、蔗糖酶活性与有机质、全氮及速效养分均呈极显著正相关。有机培肥可以显著提高土壤有机质和速效养分的含量，且对土壤脲酶、蔗糖酶、碱性磷酸酶活性有一定的改善作用。

anglais. The study was to explore the effect of different amounts and kinds of organic fertilization on soil nutrient and soil enzyme activities. A two-year (2007-2009) field experiment was carried out in Weibei Loess plateau of Shaanxi province, compared with that treated with single fertilizer, in the 0-40 cm layer, soil nutrient and enzyme activities of different application rates of straw (9 000, 6 000 kg/hm2) and manure (22 500, 11 250 kg/hm2) were determined. In 2008, compared with the control, content of organic matter increased significantly by 26.87%-33.49% in 20-40 cm layer through organic fertilizer treatments, and the content of available K increased significantly by 16.86%-35.85% and 11.34%-22.61% in 0-20 and 20-40 cm layers respectively. Content of available N and available P of the two years showed significant difference between these organic fertilizer treatments and control in 0-40 and 0-20 cm layers respectively. The activities of urease of organic fertilizer treatments showed no significant difference between organic fertilizer treatments and the control in 0-40 cm layer in the two years. Activities of alkaline phospatase showed significant difference in 0-20 cm layer in 2008, While in 2009 with the straw returning application of 9 000, 6 000 kg/hm2 and the manure application of 22 500 kg/hm2, in the 0-20 cm layer, activities of invertase increased significantly by 0.19，0.18，0.13 mg/（g•h）respectively compared with that of the control. Through correlation analysis, active relationship existed between three kinds of enzyme activities and organic matter and available nutrient. Using organic fertilizers improved the amount of organic matter and available nutrient (N, P and K), and increased the activities of urease, invertase, alkaline phospatase.