不同植茶年限土壤碳氮养分及胞外酶对干旱胁迫的响应  

The response of soil nutrients(carbon and nitrogen)and extracellular enzyme activities to drought in various cultivation ages from tea orchards

作　　者：赵杏[1] 钟一铭[1] 杨京平[1] 吕亚敏[1] 王小鹏[1] 

机构地区：[1]浙江大学环境与资源学院环境保护研究所,杭州310058

出　　处：《生态学报》2017年第2期387-394,共8页Acta Ecologica Sinica

基　　金：高等学校博士学科点专项科研基金资助项目(20130101110127);水体污染控制与治理科技重大专项资助项目(2014ZX07101-012)

摘　　要：全球气候变暖导致的夏季干旱事件频发影响茶园生态系统生产力,而茶叶是我国南方主要的经济作物,因此研究干旱条件下不同植茶年限茶园土壤养分、生态酶活性及微生物生态变化具有重要意义。选取杭州市余杭区径山茶园3种不同植茶年限(10a、30a和50a)土壤和邻近的荒土为研究对象,研究不同水分(干旱组30%WFPS(water-filled pore space)和对照组55% WFPS)处理前、第7天和第14天的土壤碳氮养分(可溶性有机碳DOC,总有机碳TOC,微生物碳MBC,微生物氮MBN,铵态氮NH_4-N,硝态氮NO_3-N)和胞外酶活性(涉碳胞外酶:β-N萄糖苷酶BG,涉氮胞外酶:N-乙酰氨基葡萄糖苷酶+亮氨酸氨基肽酶NAG+LAP)变化探讨不同水分对不同植茶年限土壤生态系统的影响。结果表明,茶园土壤碳库及涉碳、涉氮胞外酶活性随着植茶年限增加先升高后降低(30a最高);土壤氮库养分随着植茶年限增加而增加。干旱处理增加了土壤TOC、NH_4-N、NO_3-N含量而降低了土壤MBC含量、BG和NAG+LAP活性。处理前后植茶年限30a土壤DOC、MBN、NO_3-N和涉碳、涉氮胞外酶含量最高且其干旱组土壤DOC、TOC、MBC、MBN含量与对照组比变幅相对较小,可推断植茶年限30a左右的土壤微生态环境丰富,对外界环境变化的抵抗力较强。Frequent summer droughts, caused by climate change, have negatively affected the productivity and quality of tea orchard soil. Tea （Camellia sinensis L. ） is an important cash crop in southern China, therefore it is important to examine soil nutrients, enzyme activity, and microbial community structural shifts under such summer drought conditions in various cultivation ages. In this study, the pot method was utilized to investigate the soil quality of various cultivation ages of 0, 10, 30, and 50 years. These pots were incubated at 25℃ and given two different water treatments （30% and 55% WFPS （water-filled pore space） ）. Throughout the incubation period, soil samples were taken to measure the soil carbon, nitrogen content, and extracellular enzyme activities at 0, 7, and 14 days. The results indicated that prior to the incubation period, nitrate nitrogen, ammonia nitrogen, microbial nitrogen, and the total organic carbon in the soil increased with cultivation age. The microbial carbon and the extracellular enzyme activities （ 13- 1,4-glucosidase activity related to soil carbon and N-acetylglucosaminidase and 1-leucine aminopetidase activity related to soil nitrogen ） were highest at the cultivation age of 30. Soil samples taken under drought conditions, displayed increased extracellular enzyme activities, soil organic carbon, soil nitrate nitrogen, and ammonia nitrogen contents while soil microbial carbon and extracellular enzyme activities declined. The soil samples taken from a cultivation age of 30 exhibited a relatively high amount of dissolved organic carbon, microbial nitrogen, nitrate nitrogen, and soil extracellular enzyme activities throughout all incubation periods. The drought conditions had a significant influence on the contents of soil nitrate nitrogen, ammonia nitrogen, total organic carbon, and microbial carbon. Furthermore, the correlation analysis of soil carbon and nitrogen related biochemical properties indicated that the carbon and nitrogen soil nutrients affected one anoth

关 键 词：茶园土壤 植茶年限 土壤养分 胞外酶活性 干旱 

分 类 号：S158[农业科学—土壤学] S154.2[农业科学—农业基础科学]