摘要
放牧踩踏造成的土壤属性变化是引起土壤呼吸速率和碳固排波动的重要原因,但目前有关不同强度放牧踩踏对生物结皮呼吸的影响尚不明确。本研究针对黄土高原风沙土发育的藓结皮,以未干扰为对照,分别进行强度为10%、30%、50%和70%的模拟放牧踩踏干扰,连续测定了藓结皮呼吸速率的变化,分析了藓结皮呼吸速率对不同干扰强度的响应规律。结果表明:1)适度干扰会激发藓结皮呼吸速率,而重度干扰则会抑制其呼吸速率。与未干扰相比,干扰10%和30%的藓结皮呼吸速率分别增加了41.1%和22.2%,而干扰50%和70%的藓结皮呼吸速率则分别降低了8.9%和15.3%。2)踩踏干扰显著改变了土壤温度,但对土壤含水量的影响不显著。与未干扰相比,干扰10%和30%的土壤温度分别显著降低了0.4和1.2℃,干扰50%和70%则分别显著增加了1.1和1.0℃。3)不同干扰强度下藓结皮呼吸速率与土壤温度和含水量分别呈显著指数和线性正相关关系,但与藓结皮基本特性无显著相关关系,土壤温度和水分可分别解释藓结皮呼吸速率动态变化的70.6%~96.3%和49.1%~70.0%。综上,放牧踩踏显著影响了藓结皮呼吸速率,短期适度放牧踩踏会激发藓结皮呼吸速率,而过度放牧踩踏则会抑制其呼吸速率。因此,在未来黄土高原地区土壤碳收支平衡研究中应考虑不同强度放牧踩踏对生物结皮呼吸的影响。
The changes in soil properties caused by grazing and trampling are important reasons for the changes in soil respiration rates,carbon fixation,and emission.However,the effects of different intensities of grazing and trampling on biocrusts respiration rate are unclear.In this study,we simulated grazing and trampling disturbances of 10%,30%,50%,and 70%intensity on moss biocrusts developed in aeolian sandy soil on Loess Plateau,with undisturbed moss biocrusts serving as a control.The changes in respiration rate of moss biocrusts were monitored continuously,and its responses to different disturbance intensities were analyzed.The results showed that:1)moderate disturbance stimulated moss biocrusts respiration,while heavy disturbance inhibited that.The respiration rate of moss biocrusts was increased by 41.1%and 22.2%at disturbance intensities of 10%and 30%,but was decreased by 8.9%and 15.3%at disturbance intensities of 50%and 70%,respectively.2)The trampling disturbance significantly changed soil temperature but did not affect soil water content.In comparison to the control,soil temperature of biocrusts was decreased by 0.4 and 1.2℃at disturbance intensities of 10%and 30%,but it was increased by 1.1 and 1.0℃at disturbance intensities of 50%and 70%,respectively.3)The respiration rate of moss biocrusts showed a significant exponential relationship with soil temperature and a linear positive relationship with soil water content under different disturbance intensities.However,the correlation between respiration rate of moss biocrust and the characteristics of moss biocrust was not significant.Soil temperature and water content could explain 70.6%-96.3%and 49.1%-70.0%of the total variation of respiration rate of moss biocrusts,respectively.In conclusion,grazing and trampling affected the respiration rate of moss biocrusts,with short-term moderate grazing and trampling would have positive effects.On the other hand,excessive grazing and trampling would reduce the rate of moss biocrust respiration.As a result,future studies on soil carbon balance of the Loess Plateau should consider the effects of grazing and trampling on biocrust respiration.
作者
窦韦强
肖波
王彦峰
江子昊
余星兴
李胜龙
DOU Wei-qiang;XIAO Bo;WANG Yan-feng;JIANG Zi-hao;YU Xing-xing;LI Sheng-long(College of Land Science and Technology,China Agricultural University/Key Laboratory of Arable Land Conservation in North China,Ministry of Agriculture and Rural Affairs,Beijing 100193,China;State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling 712100,Shaanxi China;Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China)
出处
《应用生态学报》
CAS
CSCD
北大核心
2022年第7期1783-1790,共8页
Chinese Journal of Applied Ecology
基金
国家自然科学基金项目(42077010)
中国科学院“西部之光”人才培养引进计划项目(2019)
中央高校基本科研业务费专项资金(2021TC038)
中国农业大学2115人才工程项目(1191-00109011)资助。
关键词
适度放牧
生物土壤结皮
土壤呼吸速率
土壤温度
土壤含水量
conservative grazing
biological soil crusts
soil respiration rate
soil temperature
soil water content
