摘要
粗枝云杉(Picea asperata)是西南亚高山针叶林的主要建群种,而华西箭竹(Fargesia nitida)既是大熊猫的主食植物也是针叶林下优势物种,在该区域华西箭竹与粗枝云杉往往共存于天然林,而人工云杉林及次生箭竹林下两物种均单独存在.摸清二者单独及共存下根区土壤酶活性对气候变暖的响应,能为未来气候变化下该区域森林管理及熊猫生境恢复提供科技支撑.以箭竹和云杉为对象,采用红外加热器模拟增温,通过二者单种和混种,研究增温和植物互作对根区土壤胞外酶活性(EEA)的影响.结果显示:(1)增温显著增加了单种箭竹根区N-乙酰-β-D-葡萄糖苷酶(NAG)和β-1,4-葡萄糖苷酶(BG),以及单种云杉根区NAG、BG、蔗糖酶(Suc)、酸性磷酸酶(AP)和混种根区蛋白酶(Pro)活性,显著降低了混种根区NAG和AP活性.(2)对照时箭竹根区NAG,云杉根区NAG和脲酶(Ure)及混种根区BG和Suc活性显著高于各自非根区,但箭竹根区AP和Pro活性较非根区显著减小;增温时与非根区相比,箭竹根区BG,云杉根区NAG、Pro、BG、Suc和AP及混种根区Ure和Suc活性均显著增大,而箭竹根区Suc、云杉根区Ure及混种根区BG和AP活性显著减小.(3)冗余分析表明EEA在对照时主要受土壤pH和含水量的影响,而增温时与pH、含水量、总氮和无机氮有显著的相关性.多元回归分析显示pH和总氮分别是两种情形下酶活性变异的最佳预测因子.以上结果说明,增温对单种根区土壤酶活性有促进作用,但此作用在混种时可能被掩盖或减弱;EEA受多种因素共同调控,对EEA起主导作用的土壤理化因子在增温背景下发生改变.
To determine the effects of warming and plant interaction on the activities of extracellular enzymes(EEA)in the root zone soil,an infrared heater was used to simulate nighttime warming.Fargesia nitida and Picea asperata were planted individually or mixed in the plots.Ingrowth tubes with different cores were embedded to determine the effects of roots on soil enzyme activity in different plots.Six soil enzymes,soil C and N pools,and other soil properties were measured to evaluate the effects of warming and tree interactions on the extracellular enzymes.The results showed that(1)night warming significantly increased the activities ofβ-N-acetylglucosaminidase(NAG)and 4-methylumbelliferyl-β-D-glucoside(BG)in F.nitida root zone soil;NAG,BG,sucrase(Suc),and acid phosphatase(AP)in P.asperata root zone soil;and protease(Pro)in mixed plots.However,night warming significantly decreased the activities of NAG and AP in the mixed planted plots.(2)In the control plots,the activities of NAG in F.nitida root zone soil,NAG and urease(Ure)in P.asperata root zone soil,and BG and Suc in mixed root zone soil were significantly higher than those in soil without roots in each plot.However,Pro and AP activity in root zone soil was significantly lower than that in rootless soil in F.nitida singly planted plots.Compared with rootless soil,the activities of BG in F.nitida root zone soil;NAG,Pro,BG,Suc,and AP in P.asperata root zone soil;as well as Ure and Suc in mixed root zone soil were significantly increased under warming conditions.However,the activities of Suc in F.nitida root zone soil,Ure in P.asperata root zone soil,and BG and AP in mixed root zone soil were evidently decreased.Redundancy analysis indicated that EEA was primarily affected by soil pH and soil moisture(SM)under non-warming conditions.However,EEA is significantly correlated with pH,SM,and total nitrogen and inorganic nitrogen under warming conditions.Multiple regression analysis showed that pH and total nitrogen were the best predictors of enzyme activity under both conditions.These results suggested that warming can promote the enzyme activities of root zone soil in single F.nitida and P.asperata plots,but the favorable effect may be weakened in mixed planted plots.EEA is regulated by many factors,and the soil physical and chemical factors that play a leading role in EEA change under the influence of warming.
作者
罗林
刘庆
黄艳
郭敏
胡星
张卓婷
贺合亮
赵春章
梁进
LUO Lin;LIU Qing;HUANG Yan;GUO Min;HU Xing;ZHANG Zhuoting;HE Heliang;ZHAO Chunzhang;LIANG Jin(CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province,Chengdu Institute of Biology,Chinese Academy of Sciences Chengdu 610041,China;College of Ecology and Environment,Chengdu University of Technology,Chengdu 610059,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Life Sciences,Sichuan Normal University,Chengdu 610101,China)
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2021年第3期577-586,共10页
Chinese Journal of Applied and Environmental Biology
基金
国家自然科学基金项目(31700418,31570477)
国家重点研发计划项目(2017YFC0505000)
四川省重点研发计划项目(2021YFS0283)资助。
关键词
华西箭竹
粗枝云杉
增温
单种
混种
土壤胞外酶活性
亚高山森林
Fargesia nitida
Picea asperata
warming
planted single
planted mixed
soil extracellular enzyme activity
subalpine forest
