The influence of nitrogen fertiliser rate and crop rotation on soil methane flux in rain-fed potato fields in Wuchuan County, China.
As one of the important greenhouse gases, the characteristics and principles of methane exchange characteristics in cultivated lands have become hot topics in current climate change research. This study examines the influences of nitrogen fertilisation, temperature and soil water content on methane exchange characteristic and methane exchange functional gene-pmoA gene abundance based on experimental observations of methane exchange fluxes using the static chamber-gas chromatographic method and measurements of methanotroph gene copy numbers in three growing periods by real-time PCR in rain-fed potato fields. The results indicate that the rain-fed potato fields were a CH4 sink with an average annual methane absorption (negative emission) of 940.8±103.2 g CH4-C/ha/year. The cumulative methane absorption first exhibited flat and subsequently increasing trend with the increase of nitrogen fertilisation from 0~135 kg N·ha(-1). Methane cumulative absorption significantly increased with the increase of temperature when temperatures were below 19.6 °C. Methane oxidation capacity (methanotroph pmoA gene copy numbers) showed an increasing and subsequently decreasing trend with the increase of soil moisture. Crop rotation was observed to increase the methane absorption in rain-fed potato fields and nearly one time higher than that under continuous cropping. A mechanism concept model of the methane exchange in rain-fed potato fields was advanced in this paper.
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; College of Agronomy, Shenyang Agricultural University, Shenyang 110866, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Liwei
L
Wang
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China. Electronic address: panzhihua@cau.edu.cn.
Zhihua
Z
Pan
Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
Hui
H
Xu
College of Agricultural and Biotechnology, China Agricultural University, Beijing 100193, China.
Cheng
C
Wang
School of Resources and Environmental, Anhui Agricultural University, Hefei 230036, China.
Lin
L
Gao
Institute of Resources Environmental and Detection Technology, Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Huhhot 010031, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Peiyi
P
Zhao
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Zhiqiang
Z
Dong
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Jingting
J
Zhang
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Guohui
G
Cui
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Sen
S
Wang
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Guolin
G
Han
College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China; Wuchuan Scientific Observing and Experimental Station of Agro-Environment, Ministry of Agriculture Wuchuan 011700, China.
Hui
H
Zhao
D000383:Agriculture / Q000379:methods*; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data; D002681:China; D005308:Fertilizers; D008697:Methane / Q000032:analysis*; D009584:Nitrogen
D000393:Air Pollutants; D005308:Fertilizers; D009584:Nitrogen; D008697:Methane
CH(4) exchange; CH(4) oxidation; Crop patterns; Methanotrophs; Nitrogen fertiliser; Rain-fed potato