N2O emission and mineral N leaching from contrasting land-use hillslopes as jointly affected by climate and rock fragment factors
N2O emission and mineral N leaching from contrasting land-use hillslopes as jointly affected by climate and rock fragment factors
复制标题
受气候和岩石碎片因素共同影响的对比土地利用山坡的 N2O 排放和矿物氮淋失
DOI：
10.1002/jpln.202000105
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发表时间：
2020
影响因子：
2.5
通讯作者：
Liao Kaihua
中科院分区：
文献类型：
--
作者：
Zhou Zhiwen;Zhu Qing;Lai Xiaoming;Liao Kaihua
背景和目的：气候因子和岩石碎块含量（RFC）对土壤氧化亚氮（N2 O）排放和矿质氮淋溶的影响对于减少不同农业生态系统中的氮素损失具有重要意义。本研究旨在分析和量化的降水强度，温度，RFC，和土地利用对这两种土壤N loss.Methods的交织效应：DayCent模型进行了校准和验证，利用观测数据的代表茶园（TG），竹林（BF），混交林（MF）在中国东南部丘陵区的山坡。然后，在三种土地利用类型的组合下，模拟了总共882种情景下的N2 O排放和矿物N淋溶（TG、BF和MF），七种降水强度（PI，从8到99.2 mm d-1，但总降水量保持不变），七种温度条件结果表明：TG处理的土壤N2 O排放量最大（分别是BF和MF的1.8和3.3倍），无机氮淋失量最大（分别是BF和MF的5.5和36.8倍）。在3个土地利用类型的坡地上，土壤N2 O排放量在夏季最大，而矿质氮淋失量一般在春季和冬季最大。当PI达到59.8 mm d−1时，观察到N2 O排放的峰值，而当PI达到8.0和59.8 mm d−1时，总是观察到矿物N淋溶的峰值。随着温度的升高和RFC的降低，两种类型的土壤氮素流失量均增加。与气候因素相比，土地利用和RFC对两种类型土壤氮素流失的影响最大。在相同的RFCs条件下，PI对土壤N2 O排放的影响大于温度，而对矿质氮淋溶的影响则相反。结论：本研究结果可为石质土坡面减少土壤氮流失的措施设计提供科学依据。
Background and aims:The effects of climate factors and rock fragment content (RFC) on soil nitrous oxide (N2O) emission and mineral N leaching can be important in reducing N losses in different agroecosystems. This study aimed to analyze and quantify the intertwined effects of precipitation intensity, temperature, RFC, and land use on these two kinds of soil N losses.Methods:The DayCent models were calibrated and validated using observed data for the representative tea garden (TG), bamboo forest (BF), and mixed forest (MF) hillslopes in the southeastern hilly region of China. The N2O emissions and mineral N leaching were then simulated under a total of 882 scenarios with the combinations of three land‐use types (TG, BF, and MF), seven precipitation intensities (PI, from 8 to 99.2 mm d−1but the total precipitation amount maintained), seven temperature conditions (from baseline –1°C to baseline +2°C with 0.5°C increment), and six RFCs (from 0 to 50% in volume with 10% increment).Results:The TG had the greatest soil N2O emission (1.8 and 3.3 times of BF and MF, respectively) and mineral N leaching (5.5 and 36.8 times of BF and MF, respectively). On three land‐use hillslopes, the greatest soil N2O emissions were observed in summer, while great mineral N leaching were generally observed in spring and winter. Peaks of N2O emissions were observed as the PI reached 59.8 mm d−1, while peaks of mineral N leaching were always observed when the PI reached 8.0 and 59.8 mm d−1. With temperature increasing and RFC decreasing, both types of soil N losses increased. The land use and RFC had the primary influences on both types of soil N losses compared to climate factors. Under the same RFCs, the PI had higher influence on soil N2O emission compared to temperature, while those on mineral N leaching were just opposite.Conclusion:Findings of this study would provide scientific bases for designing strategies to reduce soil N losses on the stony‐soil hillslopes.