茶园生态系统的一氧化氮排放研究

发布时间：2018-07-01 11:47

本文选题：茶园 + 施肥　；参考：《广西大学》2015年硕士论文

【摘要】：一氧化氮(nitric oxide, NO)是大气污染物的主要成分之一,也是生物地球化学氮循环过程中的重要组成部分。施肥农田是大气NO的重要排放源。茶园是我国重要的经济作物之一,且面积居世界首位且氮肥用量高,而有关中国茶园的NO排放特征及其影响因子的研究却未见报道。本文以不同施肥处理茶园(常规施尿素、施有机肥和不施肥对照)为研究对象,利用静态暗箱法对NO排放年周期变化的田间原位测定及相关因素的研究,以期了解亚热带典型茶园的NO排放特征、揭示其排放规律及影响因素,并估算茶园年度NO累积排放量。通过本研究,得出以下结论：1.茶园施肥处理的NO排放主要集中在3-9月(春夏季)的茶树生长季,其排放量占全年总累积排放量的58%-73%；2.对照、尿素、有机肥处理的NO年排放量分别为2.85、19.42和17.04kg N·ha-1,施肥显然大幅度增加了NO排放；3.在整个观测期内,常规施尿素和施有机肥处理的NO年直接排放系数分别为3.68%和3.15%；4.与茶农常规施尿素处理相比,施有机肥处理显著降低了约12%的NO年排放量；5.土壤铵态氮含量是茶园在春夏季NO排放通量变化的主要环境控制因素。基于田间周年连续田间观测表明,相对于其他农田生态系统,我国亚热带茶园可能是一个不容忽视的NO强排放源,但需多地点多年的长期研究进一步证实。
[Abstract]:Nitric oxide (nitric oxide,) is one of the major components of atmospheric pollutants and an important component of biogeochemical nitrogen cycling. Fertilizing farmland is an important emission source of atmospheric no. Tea garden is one of the most important cash crops in China, and it occupies the first place in the world and has a high nitrogen application rate. However, no emission characteristics and its influencing factors in Chinese tea gardens have not been reported. In this paper, different fertilization treatments (conventional urea, organic fertilizer and no fertilizer control) were used to study the in situ measurement of the annual cycle of no emission in the field and the related factors. In order to understand the characteristics of no emission from typical tea plantations in subtropics, to reveal its emission rules and influence factors, and to estimate the annual no accumulative emissions in tea plantations. Through this study, we draw the following conclusion: 1. The no emission from fertilization treatment was mainly in the growing season of tea plant in March-September (spring and summer), which accounted for 58-73% of the total accumulated emissions. In contrast, the annual no emissions of urea and organic fertilizer treatments were 2.85 ~ 19.42 and 17.04kg N ha-1, respectively. Fertilization obviously increased no emission by a large margin. During the whole observation period, the annual direct no emission coefficients of conventional urea application and organic fertilizer application were 3.68% and 3.15 respectively. Compared with conventional urea application for tea farmers, organic fertilizer treatment significantly reduced the annual no emissions by about 12%. The content of soil ammonium nitrogen is the main environmental control factor for the change of no emission flux in tea garden in spring and summer. Based on the field annual continuous field observations, compared with other farmland ecosystems, China's subtropical tea garden may be a strong no emission source that can not be ignored, but many years of long-term research is needed to further confirm it.
【学位授予单位】：广西大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S571.1;S181

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