摘要
覆盖作物作为重要的农业管理措施之一,可影响土壤有机碳的周转过程。茶是中国重要的经济作物,为探究不同覆盖作物模式下茶园土壤理化性质及土壤有机碳矿化动态,该研究自2019年选取茶园中清耕(C0)、黑麦草(Lolium perenne L.)+白三叶(Trifolium repens L.)(C1)、黑麦草+白三叶+早熟禾(Poa annua L.)+红三叶(Trifolium pretense L.)(C2)、黑麦草+白三叶+早熟禾+红三叶+紫羊茅(Festuca rubra L.)+毛苕子(Vicia villosa Roth.)+波斯菊(Cosmos bipinnata Cav.)+百日草(Zinnia elegans Jacq.)(C3)作为4种覆盖作物模式,测定其表层(0—30 cm)土壤理化性质并进行了为期471 d的矿化培养,使用一级动力学方程及指数加线性常数模型来探究土壤有机碳矿化特征。结果表明,覆盖作物能显著增加表层0—30 cm土壤中硝态氮、铵态氮、微生物量碳和微生物量氮的含量(P<0.05)。4种覆盖作物模式下,表层土壤有机碳矿化速率均随培养时间增加呈“先增后降”的变化模式,平均矿化速率为C1>C0>C2>C3。该研究发现覆盖作物种类越多,矿化速率变化越小,反应越“温和”。此外,随覆盖作物种类增加,表层土壤有机碳矿化作用增强,周转周期减小,但土壤惰性碳库含量随之增加,表明随覆盖作物多样性增加,土壤矿化作用增强,同时土壤碳的固存能力也在提高。该研究表明,在中国南方广泛种植的茶园中推广覆盖作物种植可增加表层土壤碳固持能力,对促进中国茶园土壤固碳功能具有重要意义。
As one of the important agricultural management measures, cover crops can affect the turnover process of soil organic carbon. Tea is an important economic crop in China. This study explored the soil physicochemical properties and soil organic carbon mineralization dynamics under different cover crop patterns of tea gardens. Since 2019, this study has selected cleaning tillage(C0)and ryegrass(Lolium perenne L.)+white clover(Trifolium repens L.)(C1), ryegrass+white clover+annual bluegrass(Poa annua L.)+red clover(Trifolium pretense L.)(C2), ryegrass+white clover+annual bluegrass+red clover+festuca rubra(Festuca rubra L.)+hairy vetch(Vicia villosa Roth.)+cosmos(Cosmos bipinnata Cav.)+common zinnia(Zinnia elegans Jacq.)(C3) as four types of covering. The soil physicochemical properties of the surface layer(0–30 cm) were measured and the mineralization culture was carried out for a period of 471 days. The first-order kinetic equation and the exponential plus a constant model were used to explore the characteristics of soil organic carbon mineralization. It was found that cover crops could significantly increase the contents of nitrate nitrogen, ammonium nitrogen, microbial biomass carbon and microbial biomass nitrogen in the topsoil 0-30 cm(P<0.05). Under the four cover crop patterns,soil mineralization rate first increased and then decreased with the increase of the cultivation time, and the average mineralization rates showed the following order: C1>C0>C2>C3. The more cover crop species, the smaller the change in mineralization rate and the milder the response were. In addition, with the increase of cover crop species, soil mineralization rate increased and the turnover period decreased, but the carbon resistant pool increased, indicating that with the cover crop diversity and soil mineralization increased, but soil carbon sequestration also improved. This study showed that the promotion of cover crops in widely planted tea gardens in southern China could increase the surface soil organic carbon sequestration capacity. This finding is of great significance for promoting the soil carbon sequestration in tea gardens of southern China.
作者
龚玲玄
王丽丽
赵建宁
刘红梅
杨殿林
张贵龙
GONG Lingxuan;WANG Lili;ZHAO Jianning;LIU Hongmei;YANG Dianlin;ZHANG Guilong(Agro-Environmental Protection Institute,Ministry of Agriculture and Rural Affairs,Tianjin 300191,P.R.China)
出处
《生态环境学报》
CSCD
北大核心
2022年第6期1141-1150,共10页
Ecology and Environmental Sciences
基金
中国农科院科技创新工程协同创新任务(CAAS-XTCX2016015)。
关键词
覆盖作物
覆盖作物多样性
土壤有机碳矿化
茶园
一级动力学方程
cover crops
cover crop diversity
soil organic carbon mineralization
tea garden
first-order kinetic equation
