青藏高原东缘不同树种人工林对土壤酶活性及养分的影响  

Effects of afforestation with different tree species on soil enzyme activities and nutrient content in eastern Qinghai-Tibetan Plateau,China

作　　者：舒媛媛[1,2] 黄俊胜[2,3] 赵高卷 包维楷[2] 李根前[1] 庞学勇[2] 

机构地区：[1]西南林业大学,昆明650224 [2]中国科学院成都生物所,中国科学院山地生态恢复与生物资源利用重点实验室,生态恢复与生物多样性保育四川省重点实验室,成都610041 [3]中国科学院大学,北京100049

出　　处：《生态学报》2016年第2期394-402,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31270492);国家“十二五”科技支撑计划子课题(2011BAC09B04-02);中国科学院战略性先导科技专项子课题(XDA05070306)

摘　　要：为评价不同树种人工林对土壤酶及养分的影响,选择立地条件和营林方式相同的4种人工林(连香树[CJ]、油松[PT]、落叶松[LK]和华山松[PA])为研究对象,以落叶灌丛(QC)为对照,比较不同树种人工林地土壤酶活性和土壤养分的变化。结果显示:(1)造林降低了土壤酸性磷酸酶、脱氢酶、β-葡萄糖苷酶和过氧化氢酶活性,但人工造林后土壤脲酶活性增加;(2)造林也明显影响了土壤养分,与对照林地相比,除CJ人工林土壤中磷(P)略高外,造林地土壤有机碳(TOC)、氮(N)、水可提取有机碳(WEOC)和氮(WEON)、铵态氮(NH+4-N)和硝态氮(NO-3-N)均降低;(3)不同的人工林树种之间土壤养分及酶活性也存在一定的差异性,CJ和LK人工林土壤C、N、P及相关酶活性明显不同于PT和PA人工林;(4)土壤酶与养分变化有一定的相关性,除转化酶和多酚氧化酶反应较迟钝外,其它酶对环境反应较敏感。综合分析表明,在川西地区选择高密度单一树种造林并没有改善土壤养分和酶活性,在该地区选择落叶或阔叶树种造林可使土壤肥力恢复。Afforestation is known to be the main source of restoration of degraded soil fertility and a driving force of soil processes. Plant species affect quantity and quality of carbon resources in the rhizosphere, which influence the composition and diversity of microbial community in these environments. Different plant species promote proliferation of different microbial communities by releasing different amounts and types of root exudates. Moreover, plants may directly or indirectly affect soil nutrient availability by altering soil enzyme activities through releasing extraeellular enzymes and/or altering microbial community that is known to be major contributors of enzyme activities in soil. However, few studies have been conducted to elucidate the effects of afforestation with different tree species on enzyme activities and nutrients in soil. To evaluate the changes in enzyme activities and nutrients in soil after 26 years （ 1987--2013 ） of afforestation with different tree species, four plantations stands with dominant tree species （e.g., CercidiphyUum japonicum [ CJ ] , Pinus tabulaeformis [PT], Larix kaempferi ILK], and Pinus armandii [PA] ） were selected, and a native broad-leaf forest （QC） was used as control. Four plantations were cultivated under similar site conditions and same planting patterns. Seven soil enzymes including soil urease, acid phosphatase, invertase, 13-glucosidase, dehydrogenase, catalase, and polyphenol oxidase, their activities, and soil nutrients were determined. Our results showed that： （1） Afforestation significantly influenced soil enzyme activities. For example, compared with Qc, afforestation with C J, PT, LK, and PA decreased soil acid phosphatase, 13-glucosidase, dehydrogenases, and catalase activities, whereas activity of soil urease was significantly higher in CJ and LK plantations than in other stands; （2） Afforestation also significantly affected soil nutrient content. Except for total phosphates, soil total organic carbon, total nitrogen, water extractab

关 键 词：青藏高原东缘 不同树种 人工林 土壤养分 土壤酶活性 生态恢复 

分 类 号：S714.3[农业科学—林学]