| 摘要: |
| 森林生态系统是一个庞大的碳储备系统，在当前气候变暖条件下，温度变化会对森林生态系统的碳收支过程产生重要影响。该文选择长白山温带针阔混交林森林生态系统（CBS）作为研究对象，利用多年通量及小气候观测资料分析该生态系统碳收支过程对温度的响应特征，结果显示该温带森林碳交换的季节变化特征十分明显。生态系统总初级生产力GPP、生态系统呼吸Re和净生态系统碳交换NEE在2003—2008年的月平均变化显示，碳收支3个组分最大值均出现在夏季，GPP最大值出现在7月，Re最大值主要出现在8月，NEE负方向的最大值主要出现在6月或7月，表现为碳吸收。在日尺度和月尺度对温度的响应上，GPP和Re都是随温度（气温和5 cm土壤温度）呈显著的指数升高形式。在日尺度上和月尺度上， NEE对气温的响应皆是分段线性形式，先是随气温的上升而正向增大，表现为碳排放；当超过临界温度，随气温的继续上升而负值增大，表现为碳吸收。根据温度、GPP、Re以及NEE的季节的变化，每年达到最大的GPP、Re以及NEE的最适温度均不同，这表明了在气温变化的背景下，生态系统的最适温度也在随之改变，也表明了不考虑其它因素的影响，在气候变暖的背景下，长白山针阔混交林森林生态系统的GPP、Re随气温的升高增大，而NEE随气温的升高而减小。 |
| 关键词: 温带针阔叶混交林；总初级生产力；净生态系统碳交换；生态系统呼吸；温度 |
| DOI： |
| 投稿时间：2020-11-17 |
| 基金项目: |
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| The carbon balance of typical temperate mixed forest on the response characteristics of the temperature |
| SHU Ziqian,LIU Xunxun,YAO Ning,WU Lyu,LI Shuying |
| (Jianhe County Meteorological Bureau of Guizhou Province ,Jianhe 556400 ,China) |
| Abstract: |
| Forest ecosystem is the largest carbon reserve pool in terrestrial ecosystem.Under climate change,temperature changes can influence forest ecosystem carbon balance process.In this study,we choose Changbai mountain temperate mixed forest ecosystem (CBS).Using CO2 flux data and microclimate data observed from 2003 to 2008,we analyzed the responses of gross primary productivity (GPP),ecosystem respiration (Re),and net ecosystem exchange of CO2 (NEE) to temperature (air temperature and 5 cm depth soil temperature).The results showed that the seasonal variation of carbon exchange is very obvious in this forest ecosystem.Maximum carbon budget appeared in the summer.The maximum GPP in July.The maximum Re mainly appear in the August.The NEE reach maximum negative value in June or July.The GPP and Re increased with the rise of temperature (air temperature and 5 cm depth soil temperature) exponentially at daily scale and monthly scale.The response of NEE to temperature can be divided into two stages at daily scale and monthly scale.At first stage,NEE increased with the rise of temperature,which indicated carbon emissions increase with temperature increase.When the temperature was larger than the critical temperature,NEE decreased with the temperature increase.The result indicated that net carbon uptake increase with temperature.The optimum temperatures for GPP,Re,and NEE changed with changes in annual mean temperature.The annual GPP and Re in CBS increased with the rise of annual mean air temperature.As a result,the net carbon uptake decreased with the rise of temperature without considering other environmental factors effects under climate change. |
| Key words: Temperate mixed forest ecosystem；Gross primary productivity；Net ecosystem exchange of CO2；Ecosystem respiration；Temperate |
