2012-2020年内蒙古半干旱草原碳水通量关键参数观测数据集——基于长期降水格局控制实验

A dataset of observational key parameters in carbon and water fluxes in a semi-arid steppe,Inner Mongolia(2012-2020):based on a long-term manipulative experiment of precipitation pattern

增温导致全球降水格局发生显著变化,这将显著影响我国北方半干旱草原植被生长和生态系统功能。碳水通量作为生态系统功能的关键过程,决定了生态系统的碳固持能力与资源利用策略。因此,明确生态系统碳水通量对降水格局变化的响应及其控制因子,有助于评估气候变化背景下我国草原生态系统碳汇功能的变化。但是,目前关于草原生态系统碳水过程对降水格局变化响应方面尚缺乏长期的控制实验研究与观测数据。本研究基于内蒙古锡林郭勒草原长期降水格局控制实验(包括7个降水量与降水频度变化处理),采用静态箱式法,通过红外气体分析仪进行测定,对2012–2020年生态系统碳水通量交换关键过程季节动态长期观测数据进行了整理与质量控制。本数据集主要包括气象环境数据(降水量、大气温度、土壤水分含量和土壤温度等)和碳水通量数据(生态系统总初级生产力、生态系统呼吸、生态系统净碳交换量、生态系统蒸散、碳利用效率和水分利用效率)两部分。初步结果表明,干旱显著降低碳水通量,但增水对其影响不显著;所有通量相关指标在停止处理后第一年就恢复至对照水平。本数据集的发布将为进一步加深我国草原生态系统碳水循环及其耦合过程对降水格局变化响应的研究与机制理解提供重要数据基础。

Warming has led to remarkable changes in global precipitation pattern,which will significantly affect vegetation growth and ecosystem function of the semiarid grasslands in Northern China.As a key processe of ecosystem function,carbon and water flux determines the carbon sequestration capability and resource utilization strategies of ecosystems.Therefore,understanding the responses of ecosystem carbon and water fluxes to precipitation pattern changes and their controls will be helpful for the evaluation in the carbon sequestration capacity of grassland ecosystems.However,there is a lack of long-term experiments and observational data on the responses of carbon and water processes to precipitation pattern changes in grassland ecosystems.Based on the long-term precipitation pattern manipulative experiment(including seven precipitation amount and rain event frequency treatments),we collected seasonal dynamics of ecosystem carbon and water fluxes by the static chamber method connecting with infrared gas analyzer during 2012-2020 in Xilin Gol grassland,Inner Mongolia.The dataset consists of two data files,namely the meteorological environmental data file(including annual precipitation,air temperature,soil moisture,and soil temperature)and the carbon and water fluxes data file(including ecosystem gross primary productivity,ecosystem respiration,net ecosystem carbon exchange,evapotranspiration,carbon use efficiency,and water use efficiency).Preliminary data analysis has shown that the drought treatment could significantly reduce the carbon and water fluxes,while water addition treatment had no significant effect on them.All the parameters recovered to the control level in the first year after the treatment cessation.This dataset is expected to provide important data support for the understanding of the responses of carbon and water cycles and their coupling processes to future precipitation regime in grasslands of Northern China.