摘要
土地利用方式的变化对陆地生态系统碳贮量及固碳效应均具有重要影响,土地利用方式对土壤碳周转的影响是当前全球变化生态学的重要研究内容之一.以中国科学院千烟洲红壤丘陵综合开发生态站的试验样地为研究对象,选取了当地广泛分布的农田(水稻田)、果园(柑橘园)和马尾松林样地,通过添加葡萄糖和3个温度(5、15和25℃)的培养处理,探讨了不同土地利用方式对土壤碳矿化及其激发效应的影响.结果表明:土地利用方式、葡萄糖添加、培养温度对土壤碳矿化量具有显著影响,且不同因素间存在显著的交互效应.土壤碳矿化量表现为红壤性水稻土>果园红壤>马尾松林红壤(P<0.001).添加葡萄糖后土壤碳矿化表现出显著的激发效应,红壤性水稻土和果园红壤的激发效应显著大于马尾松林红壤;此外,培养温度对激发效应具有显著的影响.在培养前7天,果园红壤和马尾松林红壤的激发效应随温度升高而升高(25℃时最大),而红壤性水稻土的激发效应在15℃时最大;随着培养时间的延长,在培养后期,果园红壤的激发效应随温度的升高而降低,红壤性水稻土和马尾松林红壤的激发效应在15℃时最大.因此,不同土地利用方式对土壤碳矿化及其激发效应的影响具有较大的差异,可能是解释中亚热带地区土壤碳收支及其碳贮量变化的重要机理之一.
Changes in land-use type are crucial factors influencing soil carbon （C） storage and soil C sequestration potential. Nowadays, the effects of land-use change on the priming effect are of wide concern with regards to soil C turnover, though with uncertainty. We conducted an incubation experiment with added glucose at 5, 15, and 25 °C to investigate how changes in land-use type could influence soil C mineralization and the priming effect in croplands （paddy field）, orchards （citrus orchard）, and masson pine woodlands, which are widely distributed in the mid-subtropics of China. The results showed that soil C mineralization increased significantly with increasing incubation temperature and glucose concentration with significant interactions among the factors. Soil C mineralization differed significantly among the different land-use types （P 〈 0.001） and showed a general trend of cropland 〉 orchard 〉 masson pine woodland. The rates of soil C mineralization increased significantly with glucose added and showed an obvious priming effect. Temperature had an apparent effect on the priming effect of soil C mineralization. At the early stage of the incubation experiment （7 day）, the priming effect increased significantly with increasing incubation temperature （the largest occurring at 25 °C）. In the latter stage of incubation, the priming effects of soil C mineralization decreased gradually with an increase of temperature in the orchard, whereas the effect was greatest at 15 °C in the cropland and the masson pine woodland. Overall, land-use change exerted an apparent influence on soil C mineralization and its priming effect, which may help to explain the mechanisms underlying the control of soil C turnover and C balance.
出处
《应用与环境生物学报》
CAS
CSCD
北大核心
2014年第3期516-522,共7页
Chinese Journal of Applied and Environmental Biology
基金
国家科技支撑计划项目(2012BAC01B08)
公益性行业科研专项(201209028)
国家自然科学基金项目(31270519)资助~~
