摘要
以腾格里沙漠东南缘天然植被区藓类结皮和藻-地衣结皮-土壤为研究对象,利用开顶式生长室(OTC),采用Li-8150系统连续测定了冬季(2015年11月—2016年1月)低温环境下两类结皮-土壤呼吸的变化,分析了低温及模拟增温对两类结皮-土壤呼吸的影响.结果表明:观测期内,藓类结皮、藻-地衣结皮-土壤呼吸速率分别为-0.052~0.418、-0.032~0.493μmol·m^(-2)·s^(-1),且藓类结皮显著高于藻-地衣结皮-土壤系统.不同类型结皮-土壤呼吸速率与5 cm土壤温度和土壤体积含水量均呈显著线性正相关,增温主要是通过加速土壤水分蒸散而抑制生物结皮-土壤呼吸速率.在整个观测期,藓类结皮-土壤系统累计排放9.90 g C·m^(-2),显著高于藻-地衣结皮-土壤系统的7.00 g C·m^(-2).研究区生物结皮-土壤系统冬季累计排放7.40g C·m^(-2),是该荒漠生态系统全年碳收支的重要组成部分.
To study the effects of low temperature and simulated warming on respiration of biocrustsoil systems,intact soil columns covered by two dominant types of biocrusts(moss and algae-lichen crusts),were collected in a natural vegetation area in the southeast fringe of the Tengger Desert.Automated soil respiration system(Li-8150) was used to measure respiration rates in biocrust-soil systems under warming(by placing them in an open top chamber) and non-warming treatments in winter(from November 2015 to January 2016).During the whole observation period,soil respiration rates covered by moss crusts were significantly higher than those covered by algae-lichen crusts,which were-0.052 to 0.418 and-0.032 to 0.493 μmol·m-2·s-1,respectively.The respiration rates of the two types of biocrust-soil systems showed significant positive linear correlations with soil temperature and volumetric soil water content at 5 cm depth.Through speeding-up the evaporation rates of soil moisture,imitated warming in winter impeded respiration rates of the two biocrust-soil systems.During the whole observation period,the cumulative carbon(C) release by moss crust-soil system(9.90 g C·m-2) was dramatically higher than that of algae-lichen crust-soil system(7.00 g C·m-2).The cumulative C release by the biocrust-soil systems in this region in winter was 7.40 g C·m-2,thus comprising an important part of annual C budget in the desert ecosystems.
作者
管超
张鹏
陈永乐
宋光
周媛媛
李新荣
GUAN Chao ZHANG Peng CHEN Yong-le SONG Guang ZHOU Yuan- yuan LI Xin-rong(Shapotou Desert Research and Experimental Station, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China University of Chinese Academy of Sciences, Beijing 100049, China).)
出处
《应用生态学报》
CAS
CSCD
北大核心
2016年第10期3213-3220,共8页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(Y311491001)
中国科学院"西部之光"项目资助~~
关键词
呼吸作用
生物结皮
低温
模拟增温
respiration
biocrusts
low temperature
simulated warming