摘要
外源养分输入提高生产力是否同时促进了氮转化过程,尤其在农牧交错带脆弱草地生态系统的研究鲜见报道。为探究土壤氮转化关键过程对外源养分添加的响应,本研究依托山西右玉黄土高原草地生态系统国家定位观测研究站2017年建立的全球变化联网试验养分平台,采用原位顶盖PVC埋管法,测定了土壤氮转化速率,以及相关生物和非生物指标。结果表明:氮添加显著提高了土壤无机氮含量、土壤氮转化速率;氮磷同时添加显著提高了地上生产力。综上,氮添加促进了晋北农牧交错带草地土壤氮转化速率,但是没有显著提高生产力;氮磷同时添加对氮转化速率没有显著影响,但是显著提高了草地生产力,因此推测,单独氮添加后,植物生长受磷限制,同时添加氮磷,虽然对净氮矿化速率没有显著影响,但是能显著提升生产力,因此未来晋北农牧交错带草地管理应该考虑氮磷双重限制。
However,did the input of exogenous nutrients improve the productivity at the same time promote the N transformation process?Especially in the Agro-pastoral ecotone grassland ecosystem research is rarely reported.In order to explore the response of soil N mineralization to N and P addition,the soil net ammonification,net nitrification and net N mineralization rate were measured from 2020 to 2021 by using top-closed PVC cylinders based on the N and P addition experimental platform which was established in 2017 in Youyu Plateau Grassland Ecosystem Research Station,and the related biotic and abiotic indexes were also determined.The results showed that:N addition significantly increased soil inorganic nitrogen content and the net nitrification rate and the net nitrogen mineralization rate.N and P addition alone had no significant effect on the above-ground productivity of grassland,but the N and P addition significantly increased the above-ground productivity by 266%.In conclusion,N addition promoted the soil N transformation rate,but did not significantly improve the productivity of grassland in the Agricultural and pastoral ecotone of northern Shanxi Province.However,the N and P addition had no significant effect on the N transformation rate,but significantly improved the grassland productivity in this region.Therefore,it was speculated that the plant growth was limited by P after the single addition of N,and the N and P addition could significantly improve the productivity although it had no significant effect on the net N mineralization rate.Therefore,the dual restriction of N and P should be considered in the future grassland management in the agro-pastoral ectopic zone of northern Shanxi.
作者
韩菲
苏原
杨倩雯
王袼
常婕
赵芳草
刁华杰
董宽虎
王常慧
HAN Fei;SU Yuan;YANG Qian-wen;WANG Ge;CHANG Jie;ZHAO Fang-cao;DIAO Hua-jie;DONG Kuan-hu;WANG Chang-hui(College of Grassland Science,Shanxi Agricultural University,Taigu,Shanxi Province 030801,China;Shanxi Key Laboratory of Grassland Ecological Protection and Native Grass Germplasm Innovation,Taigu,Shanxi Province 030801,China;Youyu Plateau Grassland Ecosystem Research Station,Shanxi Agricultural University,Youyu,Shanxi Province 037200,China)
出处
《草地学报》
CAS
CSCD
北大核心
2023年第9期2759-2768,共10页
Acta Agrestia Sinica
基金
自然科学基金区域创新发展联合基金重点项目(U22A20576)
国家重点研发计划子课题(2022YFF1302801)
山西省科技厅平台专项(202104010910017)
山西农业大学高层次引进人才专项(2021XG008)资助。
关键词
氮沉降
赖草草地
净氮矿化速率
农牧交错带
养分添加
Nitrogen deposition
Leymus secalinus grassland
Net N mineralization rate
Agricultural and pastoral ecotone
Nutrient addition
