文献类型：期刊文献

中文题名：高寒沙区生物土壤结皮覆盖土壤碳通量对模拟降水的响应

英文题名：Effect of simulated precipitation on the carbon flux in biological-soil crusted soil in alpine sandy habitats

作者：辜晨[1] 贾晓红[1] 吴波[1] 成龙[1] 杨占武[2] 杨德福[3] 赵雪彬[3]

第一作者：辜晨

机构：[1]中国林业科学研究院荒漠化研究所;[2]青海省农林科学院;[3]青海共和荒漠生态系统国家定位观测研究站

年份：2017

卷号：37

期号：13

起止页码：4423-4433

中文期刊名：生态学报

外文期刊名：Acta Ecologica Sinica

收录：CSTPCD;;Scopus;北大核心:【北大核心2014】；CSCD:【CSCD2017_2018】；

基金：国家自然科学基金(41471096;41371093;41171077);中央级公益性科研院所基本科研业务费项目(CAFYBB2016ZD010)

语种：中文

中文关键词：高寒沙区;碳通量;生物土壤结皮;模拟降水

外文关键词：alpine sandy lands; carbon flux; biological soil crusts; simulated precipitation

分类号：X171.4

摘要：生物土壤结皮作为干旱半干旱地区重要的地表覆盖类型和景观特征之一,其自身具备的光合与呼吸能力对荒漠生态系统地表与大气界面中的碳交换与循环产生了重要影响。水分是干旱半干旱地区许多生态过程中的主要限制因子,能够影响生物土壤结皮的光合与呼吸过程,进而影响生物土壤结皮覆盖土壤的碳通量规律。针对高寒沙区藓类和藻类结皮为主的生物土壤结皮覆盖土壤,设置了1、2、5、10mm以及0(对照)的模拟降水梯度,利用LI-8100土壤碳通量测定系统,对模拟降水后结皮覆盖土壤的碳通量进行测定,以探讨不同结皮种类和不同强度降水对碳通量的影响。结果表明:(1)降水对生物土壤结皮覆盖土壤的净碳通量、暗呼吸均有激发作用,使碳通量在极短时间内到达峰值且与对照差异显著,但各降水量之间差异不显著。两种不同结皮覆盖类型相比,藓类结皮覆盖土壤在降水后的碳通量峰值和受降水激发的有效时间均显著高于藻类结皮。(2)两种结皮覆盖土壤在模拟降水后的48h累积碳释放随降水量的增加而增加且与对照差异显著。同时藓类结皮覆盖土壤累计碳释放显著高于藻类结皮覆盖土壤。(3)两种生物土壤结皮覆盖土壤的碳通量和土壤水分体现出显著的相关性,净碳通量和暗呼吸均随水分的增加而增加。因此,在降水条件下生物土壤结皮覆盖土壤表现出明显的碳源效应,其碳通量以及碳释放量都有显著的改变,在研究干旱半干旱地区碳交换规律时应该考虑不同生物结皮的覆盖和降水事件的影响。
Biological-soil crusts, a community of cyanobacteria, lichens, and mosses that live on the soil surface, are a critical part of land cover types in desert ecosystems. They play a significant role in many biogeochemical processes, contributing to soil fertility, stability, and vascular plant establishment. The photosynthetic and respirometric activity of biological-soil crusts can affect carbon fluxes and exchange in desert ecosystems. Water is the major limiting factor of ecosystem functions and processes in arid and semi-arid regions. In environments with dry climates, scarce precipitation, and water shortages, water can affect the photosynthesis and respiration of biological-soil crusts, leading to changes in carbon fluxes and exchange in the soil. In the present study, to determine the effect of biological-soil crusts on soil carbon fluxes under different amounts of precipitation, we used the two dominant soil crusts types found in the Qinghai-Tibet Plateau alpine sandy vegetated areas： moss and algae. Five different simulated precipitation amounts （1, 2, 5, 10, and 0 mm） were applied, and the carbon flux of soil covered by biological crusts was measured using Li-8100 in the dark as dark respiration and in the light as the net carbon flux. The results show that the： （1） net carbon flux and dark respiration of biological-soil crusted soil were stimulated by simulated precipitation, and increased rapidly to their maximum levels. There was a significant difference between the precipitation treatments and control, but no significant difference between different treatments. The maximum carbon flux and stimulated available time of moss-crusted soil were much higher and longer, respectively, than those of algae-crusted soil; （2） total accumulated carbon release of two crusted soils after the addition of simulated precipitation increased with increasing precipitation, and there was a significant difference between carbon release in the precipitation treatments and the control. The total accumulated carbon release of moss-crusted soil was significantly more than that of algae-crusted soil; （3） carbon flux of two crusted soils and the soil volumetric water content showed a significant correlation. The effects of soil water on net carbon flux and dark respiration were stimulative. The results of the analysis indicated that the biological-crusted soil showed an effect of the carbon source after the addition of simulated precipitation. Precipitation can directly influence the carbon flux and release, and the response of the carbon flux in biological-soil crusted soil to simulated precipitation should be considered when studying carbon exchange in arid and semi-arid regions.