Understanding the mechanisms for the lower nitrous oxide emissions from fodder beet urine compared with kale urine from dairy cows
Understanding the mechanisms for the lower nitrous oxide emissions from fodder beet urine compared with kale urine from dairy cows
复制标题
了解饲料甜菜尿中一氧化二氮排放量低于奶牛羽衣甘蓝尿中一氧化二氮排放量的机制
DOI：
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发表时间：
2017
影响因子：
3.6
通讯作者：
Ji‐Zheng He
中科院分区：
文献类型：
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作者：
B. Yao;H. Di;K. Cameron;A. Podolyan;Ju;Ji‐Zheng He
研究目的一氧化二氮（N2O）是一种强温室气体，由土壤硝化和反硝化过程产生。以前的研究报告了明显较低的N2O排放量奶牛尿从饲料甜菜厂比羽衣甘蓝植物，虽然基础机制知之甚少。在这里，我们报告了一个实验室培养研究，以提高对两种不同的饲料植物，饲料甜菜（FB）和羽衣甘蓝的不同N2O排放的可能机制的理解。材料和方法处理包括两个尿源从奶牛放牧FB或羽衣甘蓝和两种土壤（FB土和羽衣甘蓝土）：FB土对照、FB土+ FB尿、FB土+羽衣甘蓝尿、羽衣甘蓝土对照、羽衣甘蓝土+ FB尿和羽衣甘蓝土+羽衣甘蓝尿。结果表明，在新西兰秋、冬季土壤中，尿素处理和尿素处理的N_2O排放总量均显著低于芥蓝处理（P < 0.05）。氨氧化细菌（AOB）在FB土壤+尿液中的生长延迟，与羽衣甘蓝土壤与尿液相比，这导致FB土壤中的氨氧化较慢。反硝化菌群落没有受到显着影响的尿液或土壤treatment.ConclusionsThese结果表明，有植物次生代谢产物（PSM）在FB尿液或根分泌物在FB土壤，这可能有抑制AOB的生长和硝化过程，导致较低的N2O排放在FB土壤或尿液。需要进一步研究来确定不同饲料植物尿液的化学成分，并确定不同饲料植物尿液或土壤中潜在的PSM或根分泌物。
PurposeNitrous oxide (N2O) is a potent greenhouse gas and is produced in the soil by nitrification and denitrification processes. Previous studies have reported apparent lower N2O emissions from dairy cow urine from fodder beet plants than from kale plants, although the underpinning mechanisms were poorly understood. Here, we report a laboratory incubation study to improve understanding of possible mechanisms underpinning different N2O emissions from two different forage plants, fodder beet (FB) and kale.Materials and methodsThe treatments included two urine sources from cows grazing FB or kale and two soils (FB soil and kale soil): FB soil control, FB soil + FB urine, FB soil + kale urine, kale soil control, kale soil + FB urine and kale soil + kale urine. The incubation temperature was 10 °C to simulate New Zealand autumn/winter soil temperatures.Results and discussionResults showed that the total N2O emissions from FB urine treatment and from urine treatments in the FB soil were lower than those from kale urine in the kale soil (P < 0.05). There was a delay in the ammonia-oxidising bacteria (AOB) growth in the FB soil + urine compared with that in kale soil with urine and this led to slower ammonia oxidation in the FB soil. Denitrifier communities were not significantly affected by the urine or soil treatments.ConclusionsThese results suggest that there are plant secondary metabolites (PSMs) in the FB urine or root exudates in the FB soil, which might have inhibited the AOB growth and the nitrification process which led to lower N2O emissions in the FB soil or urine. Further research is needed to determine the chemical composition of urine from different forage plants and to identify potential PSMs or root exudates in the urine or soil from different forage plants.