Premium
Soil temperature and bacterial diversity regulate the impact of irrigation and fertilization practices on ecosystem respiration
Author(s) -
Fan Yaqiong,
Hao Xinmei,
Carswell Alison,
Misselbrook Tom,
Ding Risheng,
Li Sien,
Kang Shaozhong
Publication year - 2021
Publication title -
agronomy journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 131
eISSN - 1435-0645
pISSN - 0002-1962
DOI - 10.1002/agj2.20613
Subject(s) - agronomy , irrigation , environmental science , fertilizer , soil respiration , ecosystem , lycopersicon , growing season , biology , ecology
Understanding ecosystem respiration ( R eco ) response to various management practices is important for the sustainable development of solar greenhouse systems, which represent a large and profitable industry in Northwest China. A tomato ( Lycopersicon esculentum Mill.)–cucumber ( Cucumis sativus L.)–tomato rotation experiment was conducted with four treatments including two irrigation levels (regular irrigation [RI] and low irrigation [LI]) and two N fertilizer sources (organic‐N fertilizer [N1] and inorganic‐N fertilizer [N2]). Ecosystem respiration and soil variables were measured multiple times. Mean R eco flux was 511, 319, and 437 mg m –2 h –1 for tomato‐2016, cucumber‐2016, and tomato‐2017, respectively. Soil temperature was the most important factor affecting R eco magnitude. Tomato seasons with higher temperature had significantly greater R eco flux than the cucumber season. Organic‐N fertilizer application can stimulate R eco flux, cumulative R eco , and R eco intensity mainly by providing favorable soil N and C condition for soil bacterial growth and activity, whereas the difference between irrigation levels was inconsistent. The fitted exponential function describing the relationship between R eco and soil temperature showed that the temperature sensitivity decreased from tomato‐2016 to tomato‐2017 for all treatments, corresponding to the continuously reduced soil bacterial alpha diversity. Soil bacterial Shannon index was an effective prediction factor for R eco in the relatively warmer and drier season, with an R 2 >.8 during tomato‐2017. The RIN1 treatment consistently had the greatest cumulative R eco and the highest soil bacterial alpha diversity throughout the rotation. Further studies are needed on the mechanisms of how the change of soil properties would regulate the response of R eco to soil abiotic and biotic factors.