增温对亚热带杉木人工林土壤微生物呼吸及熵值的影响  

Effects of warming on soil microbial respiration and entropy in subtropical Chinese fir(Cunninghamia lanceolata)plantation

作　　者：雷骋昊 苏香萍 王云 陈相标 熊德成[1,2] 陈仕东 杨智杰[1,2] LEI Chenghao;SU Xiangping;WANG Yun;CHEN Xiangbiao;XIONG Decheng;CHEN Shidong;YANG Zhijie(School of Geographical Sciences,Fujian Normal University,Fuzhou 350117,China;Fujian Sanming Forest Ecosystem National Observation and Research Station,Sanming 365002,China)

机构地区：[1]福建师范大学地理科学学院,福州350117 [2]福建三明森林生态系统国家野外科学观测研究站,三明365002

出　　处：《生态学报》2024年第14期6186-6194,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(31930071,32192433,32271727);福建省自然科学基金项目(2023I0010)。

摘　　要：增温通过改变微生物生物量和微生物代谢状况影响土壤微生物呼吸。然而,有关亚热带地区土壤微生物呼吸如何响应长期土壤增温尚不清楚。以增温7年后的杉木人工林为研究对象,比较增温对杉木人工林土壤微生物呼吸和微生物代谢熵的影响。结果表明:(1)增温后,微生物生物量碳在8月份和12月份分别降低了32.1%和59.8%(P<0.05)。(2)增温后土壤基础呼吸与底物诱导呼吸与对照相比均无显著差异;水分添加后,与基础呼吸相比,增温和对照的土壤呼吸在8月显著增加了38.3%和104.8%;葡萄糖添加后,增温和对照的底物诱导呼吸在8月份分别显著增加了113.1%和152.9%,在12月份分别显著增加了118.0%和160.9%(P<0.05)。(3)增温后,微生物代谢熵在12月显著增加了127.7%,8月无显著变化(P<0.05)。(4)在增温和对照处理中,微生物代谢熵与可溶性有机碳和微生物生物量碳含量呈负相关,与土壤含水率正相关(P<0.05)。研究结果表明,土壤增温7年后碳的可利用性和水分的降低是影响杉木人工林土壤微生物呼吸的重要因素。Increasing global temperatures have accelerated the soil carbon cycle,greatly affecting the carbon dynamics in forest ecosystem.Warming also impacts the growth and metabolism of soil microorganisms,influencing the decomposition of organic matter,and then affects soil respiration.However,it remains unclear how soil microbial respiration responds to long⁃term soil warming in subtropical areas.In this study,we investigated the effects of long⁃term soil warming on soil carbon dynamics by measuring soil basal respiration and substrate⁃induced respiration.Soil samples were taken from a depth of 0—10 cm in control and warming(7years,+4℃)plots in August and December,respectively.Glucose solution or an equal volume of deionized water was added to the soil samples,with the original soil serving as the control.The soil was incubated at 25℃for 4 hours,and soil basal respiration and substrate⁃induced respiration were measured to analyze the effects of warming on soil microbial respiration and microbial metabolic entropy(qCO_(2)).We found that:(1)Soil warming significantly decreased soil microbial biomass carbon(MBC)by 32.1%and 59.8%in August and December,respectively(P<0.05).(2)Soil warming did not significantly affect the response of the soil basal respiration and substrate⁃induced respiration,possibly due to the thermal adaptation of microorganisms.Moreover,after water supplementation,soil respiration in the warming and control plots significantly increased by 38.26%and 104.81%in August,compared to soil basal respiration.This increase suggests that soil moisture is a crucial factor affecting soil microbial respiration.After glucose supplementation,substrate⁃induced respiration significantly increased by 113.05%and 152.87%in August and 117.98%and 160.92%in December,respectively,indicating that substrate availability is another key factor affecting soil microbial respiration.(3)Soil warming increased microbial metabolic entropy by 127.7%in December,but there was no significant difference in August,which was

关 键 词：增温 微生物呼吸 代谢熵 杉木人工林 

分 类 号：S714.3[农业科学—林学]