Biocrusts Modulate Responses of Nitrous Oxide and Methane Soil Fluxes to Simulated Climate Change in a Mediterranean Dryland
Biocrusts Modulate Responses of Nitrous Oxide and Methane Soil Fluxes to Simulated Climate Change in a Mediterranean Dryland
复制标题
DOI：
10.1007/s10021-020-00497-5
复制
发表时间：
2020-03-30
期刊：
影响因子：
3.7
通讯作者：
Maestre, Fernando T.
中科院分区：
文献类型：
--
作者：
Lafuente, Angela;Duran, Jorge;Maestre, Fernando T.
生物结壳在调节旱地N2O和CH4通量对气候变化的响应方面的作用知之甚少。在这里，我们的目标是通过在西班牙中部进行为期8年的实地实验来帮助填补这一知识空白，在那里，温度和降雨量被操纵（类似于1.9摄氏度的变暖，33%的降雨量减少及其组合），在有和没有发达的生物结壳社区的地区。与发育不良的生物结壳地区相比，最初高覆盖的地区表现出较低的N2O排放量，增强CH4吸收和较高丰度的功能基因与N2O和CH4通量。此外，生物结皮调制的气体排放和相关功能基因的变暖和降雨量减少的反应。具体而言，我们发现下降雨排除和它的组合与变暖的急剧减少N2O通量（类似于96%和类似于197%，分别），只有在发达的生物结壳覆盖。气候变暖及其与降雨排除相结合，减少了CH4的消费，在最初的低覆盖的发达的生物结壳的地区，而降雨排除增强CH4的吸收，只有在最初的高覆盖的发达的生物结壳的地区。同样，结合变暖和降雨排除增加了丰度的nosZ基因相比，降雨排除治疗和增加了丰度的pmoA基因相比，控制，但仅在低生物壳覆盖的地区。综上所述，我们的研究结果表明，发达的生物结壳社区可以抵消气候变暖和降雨模式改变对土壤N2O和CH4通量的影响，突出了它们的重要性和保护它们的必要性，以尽量减少气候变化对旱地的影响。
Little is known about the role of biocrusts in regulating the responses of N2O and CH4 fluxes to climate change in drylands. Here, we aim to help filling this knowledge gap by using an 8-year field experiment in central Spain where temperature and rainfall are being manipulated (similar to 1.9 degrees C warming, 33% rainfall reduction and their combination) in areas with and without well-developed biocrust communities. Areas with initial high cover of well-developed biocrusts showed lower N2O emissions, enhanced CH4 uptake and higher abundances of functional genes linked to N2O and CH4 fluxes compared with areas with poorly developed biocrusts. Moreover, biocrusts modulated the responses of gases emissions and related functional genes to warming and rainfall reductions. Specifically, we found under rainfall exclusion and its combination with warming a sharp reduction in N2O fluxes (similar to 96% and similar to 197%, respectively) only under well-developed biocrust cover. Warming and its combination with rainfall exclusion reduced CH4 consumption in areas with initial low cover of well-developed biocrust, whereas rainfall exclusion enhanced CH4 uptake only in areas with high initial cover of well-developed biocrusts. Similarly, the combination of warming and rainfall exclusion increased the abundance of the nosZ gene compared to the rainfall exclusion treatment and increased the abundance of the pmoA gene compared to the control, but only in areas with low biocrust cover. Taken together, our results indicate that well-developed biocrust communities could counteract the impact of warming and altered rainfall patterns on soil N2O and CH4 fluxes, highlighting their importance and the need to preserve them to minimize climate change impacts on drylands.