• 论文与研究报告 •

肥培毛竹林土壤氨挥发特征

1. 1. 国际竹藤中心 国家林业局竹藤科学与技术重点实验室 北京 100102;
2. 西南林业大学 昆明 650224
• 收稿日期:2015-11-13 修回日期:2016-04-14 出版日期:2016-11-25 发布日期:2016-12-16
• 通讯作者: 苏文会
• 基金资助:
科研事业费项目（1632014011）；国家林业局948项目（2014-4-58）。

Characteristics of Soil Ammonia Volatilization in Fertilized Moso Bamboo (Phyllostachys edulis) Forests

Zhao Jiancheng1, Su Wenhui1, Fan Shaohui1, Cai Chunju1, Zhu Xiaowu1,2, Liu Guanglu1

1. 1. Key Laboratory of Science and Technology of Bamboo and Rattan of State Forestry Administration International Centre for Bamboo and Rattan Beijing 100102;
2. Southwest Forestry University Kunming 650224
• Received:2015-11-13 Revised:2016-04-14 Online:2016-11-25 Published:2016-12-16

Abstract: [Objective] Nitrogen (N) is the greatest demand element for Moso bamboo (Phyllostachys edulis) growth. Improper fertilization could result in the decrease of nitrogen use efficiency (NUE) and the increase of nitrogen loss. Ammonia (NH3) volatilization is one of the main pathways of nitrogen loss from soil. Improper depth of fertilizer application in the soil could accelerate the loss of NH3 volatilization. However, very little information is available regarding NH3 volatilization and its influence factors in Moso bamboo forests. Thus, in this study the NH3 volatilization characteristics at different fertilization depths in a Moso bamboo forest were investigated by field experiment to provide the scientific guidance for the reasonable fertilization depth in terms of reducing the ammonia volatilization. [Method] In this paper, seven fertilization depths of 0, 5, 10, 15, 20, 25 and 30 cm and a control treatment without fertilizer were set in Huangshan, Anhui Province of China. The NH3 volatilized from each plot was absorbed by 2% H3BO3 with the venting method. One-way ANOVA was conducted to test the significance of the indexes, and the least significant difference (LSD) was applied for multiple comparisons. [Result] The NH4+ content after fertilization increased first and then declined with the extension of time, and finally stabilized. The NH3 volatilization showed obvious regularity changes with time, and it was closely related to fertilization depth. NH3 volatilization was detected on the second day after fertilization. The NH3 volatilization rates of all fertilization treatments increased first and then decreased, showed a single peak curve. NH3 volatilization rates at fertilization depths of 0, 5 and 10 cm peaked on the third day, while rates of NH3 volatilization at fertilization depths of 15, 20, 25 and 30 cm reached a maximum in 6 days after fertilization. Then, the rates decreased gradually. About twelve days later, NH3 volatilization rates dropped to a low level similar to the control. NH3 volatilization of urea could be divided into 2 stages, namely, rapidly and slowly increasing stages. The first eight days were recognized as the rapidly increasing stage. The ratios of NH3 volatilized within the first eight days to the total volatilization loss were ranged from 81.93% to 92.38%. Then it changed to the slowly increasing stage. The relationship between the cumulative NH3 volatilization (y) and the corresponding time (t) accorded with the Elovich equation (y=a + b lnt). By the end of this experiment, the losses of NH3 volatilization from the fertilization treatments were ranged from 10.12 to 27.17 kg·hm-2. Results showed that NH3 volatilization was influenced significantly by fertilization depth. The mean NH3 volatilization flux and total loss decreased with the increase of fertilization depth. NH3 volatilization losses of fertilization placed at 0 and 5 cm depths were larger than that at other depths, up to 27.17 and 25.66 kg·hm-2, equivalent to 21.05% and 19.88% of the applied N, respectively. When fertilization depth exceeded 15 cm, the loss ratio was significantly reduced. [Conclusion] In this study, NH3 volatilization was characterized by a high speed within the first eight days after fertilization in an intensive management bamboo forest. Thus, the regulation of environmental conditions was suggested to reduce N loss. The nitrogen losses through NH3 volatilization of fertilization placed below 15 cm depth were lower, however deep fertilization application could result in leaching loss and also increased the production cost. Comprehensive consideration of the distribution of bamboo root and nitrogen loss and utilization, the reasonable fertilization depth should be 15-20 cm in P.edulis forests.