北京林业大学学报2017，Vol.39Issue(6)：51-59,9.DOI:10.13332/j.1000-1522.20170029
密度调控对长白落叶松人工林土壤呼吸的影响
Effects of density control on soil respiration in Larix olgensis plantation
摘要
Abstract
In order to investigate the mechanism of density control on soil respiration in a north temperate forest, the soil respiration rate was measured using LI-6400 during the growing season in Larix olgensis plantations with different stand densities of P1 ( 300 -350 plants/ha ) , P2 ( 500 -550 plants/ha ) , P3 (600-650 plants/ha) and P4 (850-900 plants/ha) . The results showed that soil respiration rate showed seasonal pattern, with the highest value in late August and the lowest in the middle of October. Soil respiration rate and cumulative soil CO2-C efflux decreased significantly in different forest stands with the increase of stand density ( P <0. 05 ) . There was a significant exponential correlation between soil respiration and soil temperature, but it was not significant with soil respiration and soil water content. The two-factor model fitted better, 73. 1% -81. 0% soil respiration rate was explained by soil temperature and soil water content;Q10 , the soil respiration temperature sensitivity coefficient was expressed as 300-350 plants/ha at the lowest ( 2. 41 ) and 500 -550 plants/ha at the highest ( 3. 32 ) . The biotic factor significantly increased with the increase of stand density ( P<0. 05 ) , and the abiotic factors decreased with the increase of stand density ( P <0. 05 ) . There was an extremely significant positive correlation between soil CO2-C efflux and abiotic factors ( P <0. 001 ) , and soil CO2-C efflux was correlated with biological factors extremely negatively (P<0. 001) during the growing season. Stepwise linear regression analysis showed that litter biomass in growing season, soil organic carbon, microbial biomass carbon content and soil total nitrogen content were most closely related to soil respiration. The results showed that the difference between soil temperature, water content and biotic factor, abiotic factors with different density stand was the primary reason causing the difference of soil CO2-C efflux. In the forest management, the density of stands should be set at 850-900 plants/ha to reduce soil CO2 emissions.关键词
密度调控/长白落叶松人工林/土壤呼吸/Q10Key words
density control/Larix olgensis plantation/soil respiration/Q10分类
农业科技引用本文复制引用
邵英男,田松岩,刘延坤,李云红,陈瑶,孙志虎..密度调控对长白落叶松人工林土壤呼吸的影响[J].北京林业大学学报,2017,39(6):51-59,9.基金项目
黑龙江省科技攻关项目(GC12C203)、黑龙江省林业科学院青年基金项目(N201414)、国家自然科学基金面上项目(41275154). （GC12C203）
