牛粪对杨树人工林土壤生物学性状及其生长的影响

目的]探讨施用牛粪对杨树人工林土壤生物学性状与生长的作用效果,为土壤培肥制度的建立及杨树人工林的合理施肥提供理论依据。方法]通过3a大田试验,研究CK(对照,不施肥)、CF(单施化肥)、CM(牛粪)和CM+CF(牛粪和化肥各提供50%的氮)等处理对杨树人工林土壤理化特征、微生物数量、微生物量碳氮、活性有机碳、碳库管理指数(CPMI)及生长的影响。结果]与CF处理相比,CM+CF处理显著提高了土壤中细菌数、真菌数、微生物总量和微生物量碳、氮含量,其中微生物量碳、氮含量分别较CF处理显著提高42.20%和43.75%;CM+CF处理还能明显提高土壤中碱解氮、速效磷、速效钾和交换性Mg含量,并显著降低土壤pH值。同时,CM处理使土壤总有机碳含量达最高值,而CM+CF处理使土壤的低活性、中活性、高活性有机碳含量和CPMI最高,其中CPMI分别较CK,CF和CM处理显著高出52.76,47.16,25.89。此外,CM+CF处理使杨树人工林的材积平均生长率达到45.36%,并显著高于其他处理。与CM+CF处理相比,CM处理对土壤和材积的影响效果较小。结论]牛粪与化肥配施有助于改善杨树人工林土壤的生物学性状,有利于促进林木生长。

Effects of Cattle Manure on Soil Biological Characteristics and Growth of Poplar Plantation

Objective] Exploring the effects of cattle manure application on soil biological characteristics and growth of poplar plantation, to provide theoretical basis for the establishment of soil fertility system and reasonable fertilization of poplar plantation.Methods] A field experiment with four treatments, i. e. CK (neither urea nor cattle manure was applied), CF (100% of nitrogen was provided by urea), CM (100% of nitrogen was provided by cattle manure), and CM+CF (50% and 50% of nitrogen was provided by cattle manure and urea, respectively) was conducted to determine effects of different treatments on physicochemical properties, microbial populations, microbial biomass carbon, microbial biomass nitrogen, active organic carbon, carbon pool management index (CPMI) and growth of poplar plantation.Results] In comparison to CF treatment, CM+CF treatment significantly increased the populations of bacteria, fungi and total microorganism, and the contents of microbial biomass carbon and microbial biomass nitrogen increase 42.20% and 43.75%, respectively. The contents of available nitrogen, available phosphate, available potassium and exchangeable Mg were significantly increased by CM+CF treatment, while the pH value was obviously decreased. Meanwhile, the maximum value of total organic carbon content was observed in CM treatment, whereas the contents of low-labile, moderate-labile and high-labile organic carbon, and CPMI were notably increased by CM+CF treatment, indicative of 52.76, 47.16 and 25.89 increases in CPMI over the values of CK, CF and CM, respectively. Additionally, the average volume growth rate in CM+CF treatment was 45.36%, which was significantly higher than those of other treatments. However, in CM treatment, fewer effects on soil and volume of poplar were observed in comparison with the one of CM+CF treatment.Conclusion] Cattle manure co-applied with inorganic fertilizer was beneficial to improve soil biological characteristics and promote the growth of poplar plantation.