Zhang Ke-Bin, Liu Xin-Liang, Kang Man, Wang Yi, Shen Jian-Lin, Li Yong
Key Laboratory of Agro-ecological Processes in Subtropical Regions, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China.
Changsha Research Station for Agricultural & Environmental Monitoring, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, China.
Huan Jing Ke Xue. 2020 May 8;41(5):2434-2444. doi: 10.13227/j.hjkx.201911090.
A large amount of fertilizers are applied to the tea plantations resulting in high nitrous oxide (NO) emissions. The area of Chinese tea plantations has been expanding in recent years, making them an important source of agricultural NO emissions. There is an urgent need for effective mitigation measures for NO emissions from tea plantations. In this study, the NO emission flux and related environmental factors are measured in Chinese mid-subtropical typical hilly tea plantation under three kinds of management measures, namely intercropping sorghum, applying big urea pills, and under conventional fertilization conditions. The aim of this experiment is to determine the main factors controlling NO emissions from the soils of the tea plantation and confirm the true effectiveness of the proposed NO emission mitigation measures. The results of a 2-year field experiment show that:① NO emissions were significantly correlated with soil chemical properties, temperature and rainfall, interaction between soil physical and chemical properties; soil chemical properties have the greatest impact on soil NO emissions. The concentration of soil NO-N is the most important factor determining the size of NO flux in the tea plantation. The most important task of NO emission mitigation research in the tea plantation is to reduce the concentration of soil NO-N; ② sorghum intercropping reduces NO emissions by 51.2% while not affecting the tea yield. From the perspective of mitigating global warming, sorghum intercropping is the best tea plantation management measure per the results of this study; ③ applying big urea pills effectively increases tea yield while simultaneously reducing the NO emissions by 34.7%. From the perspective of balancing economic benefits as well as mitigating global warming, application of big urea pills is undoubtedly the best tea plantation management measure as indicated by this study.
大量肥料被施用于茶园，导致一氧化二氮（NO）排放量很高。近年来，中国茶园面积一直在扩大，使其成为农业NO排放的一个重要来源。迫切需要采取有效的措施来减少茶园的NO排放。在本研究中，在中国中亚热带典型丘陵茶园中，在三种管理措施下测量了NO排放通量及相关环境因素，这三种措施分别是间作高粱、施用大颗粒尿素丸以及常规施肥条件。本实验的目的是确定控制茶园土壤NO排放的主要因素，并确认所提出的NO减排措施的实际效果。一项为期两年的田间实验结果表明：①NO排放与土壤化学性质、温度和降雨、土壤理化性质之间的相互作用显著相关；土壤化学性质对土壤NO排放的影响最大。土壤NO-N浓度是决定茶园NO通量大小的最重要因素。茶园NO减排研究的最重要任务是降低土壤NO-N浓度；②间作高粱可减少51.2%的NO排放，同时不影响茶叶产量。从缓解全球变暖的角度来看，根据本研究结果，间作高粱是最佳的茶园管理措施；③施用大颗粒尿素丸可有效提高茶叶产量，同时减少34.7%的NO排放。从平衡经济效益以及缓解全球变暖的角度来看，本研究表明，施用大颗粒尿素丸无疑是最佳的茶园管理措施。
