茶园土壤氮含量、施氮效应及其 N2O 排放的研究进展

氮素是茶树生长和发育的必需营养元素之一，供应状况直接影响茶叶的产量与品质。本文在总结了茶园土壤氮含量的基础上，综述了氮肥对茶叶产量、品质及 N2O 排放的影响，主要包括：随着化学氮肥的大量施用，茶园土壤氮素含量明显增加；合理的施氮量能显著提高茶叶产量并改善其品质，不足或过量均会抑制茶树产量和品质；茶树为喜铵作物，施用铵态氮肥有利于茶树品质的形成；成龄茶园施 N 量200．0～350kg·hm－2， N∶P∶K 配比2∶1∶1为宜，同时配施适量有机肥；施用氮肥显著促进茶园土壤 N2O 的排放。结合茶叶氮素需求特征，提出今后进一步加强氮素利用的技术对策。

Nitrogen Content,Response to Nitrogen Fertilization and N2 O Emission of Soil at Tea Plantations

Nitrogen is one of the essential nutrients for tea growth？and？development.Its supply directly affects teayield and quality.This article reviews and analyzes the current status of the nitrogen in soil at tea plantations inChina,the effects of the amount,forms and ratio in NPK fertilizers of nitrogen on tea plants,as well as the N2 Oemission mechanism and associated factors.Chemical nitrogen fertilizer has a significant effect on the total nitrogencontent in the soil at tea plantations.Appropriate application of nitrogen could remarkably improve tea yield andnutrition quality.But,excessive applications,either too high or too low a nitrogen level,could stunt the growth.Nitrogen fertilizers,such as ammonium and ammonium-nitrogen,normally benefit the tea quality.It is generallyconsidered adequate for tea fertilization at the rate of N 200.0-3 50 kg·hm-2 ,and a N∶P∶K ratio of 2 ∶1 ∶1 .Since nitrogen fertilization can significantly increase N2 O emission,its application directly affects the air quality.Consequently,in order to maximize nitrogen fertilization efficiency while minimize air pollution to the environment,appropriate managerial strategies must be implemented.