Carbonate influences on the biogeochemical processes driving the stabilization of soil organic carbon in drylands

气候变化导致的气温上升和干旱加剧加剧了旱地的土壤退化和荒漠化，对粮食安全构成了重大威胁。土壤有机碳(SOC)流失是土壤退化和荒漠化的重要驱动因素。增加土壤有机碳可以缓解土壤退化，但旱地土壤有机碳储量可能很少，关键是，大多数土壤碳素以碳酸盐(SIC)形式存在。碳化硅可能通过形成碳化硅-有机-矿物结构的成土过程来调节土壤矿物基质中有机碳的物理稳定性。成土过程可能通过控制微生物对底物的物理访问来增加SOC的稳定性，但它们如何间接改变微生物过程和SOC的分解/稳定尚不清楚。为此，SIC-SOC-STRISE的目标是1)使用已建立的数据集来量化SIC对旱地SOC稳定的全球影响，以及2)验证沿着局部场梯度的全球模式，并产生关于碳酸盐成土作用驱动的物理稳定结构如何影响驱动SOC稳定的微生物过程的详细理解。此外，考虑到土壤管理对旱地土壤有机碳储存的影响是根本的，因为土壤耕作可以加速碳酸盐成土。它通过3)通过实验量化土壤扰动对碳酸盐土壤成土的影响和微生物介导的有机碳储存的命运，阐述了IPCC推荐的管理措施的农业意义，如减少耕作对石灰性土壤有机碳稳定的影响。最后，由于减少耕作需要更大的机械除草，这一角色主要落在农村旱地的妇女身上，拟议的MSCA在倡导增加碳排放的最佳做法时考虑了劳动力中的性别差异。为了实现这一点，它开发了一种科学上强有力的培训和支持工具，赋予妇女权力并使其具备在农业管理中担任关键角色的能力。

Increasing temperatures and worsening drought from climate change are exacerbating soil degradation and desertification indrylands, presenting a major threat to food security. Soil organic carbon (SOC) loss is a strong driver of soil degradation anddesertification. Increasing SOC can mitigate soil degradation, but dryland SOC stocks can be minimal, and critically, most soil carbonin drylands exists as carbonate (SIC). SIC likely moderates the physical stabilization of SOC in the soil mineral matrix via pedogenicprocesses that form SIC-organo-mineral structures. Pedogenic processes may increase SOC stabilization by controlling physical accessof microorganisms to substrate, but it's unclear how they indirectly alter microbial processes and SOC decomposition/stabilization. Tothis end, SIC-SOC-STABLE aims to 1) quantify the global influence of SIC on SOC stabilization in drylands using an established dataset,and 2) validate global patterns along a local field gradient and to generate a detailed understanding of how physical stabilizationstructures, driven by carbonate pedogenesis influence the microbial processes driving SOC stabilization. Further, considering theimpacts of soil management on SOC storage in drylands is fundamental given that soil tillage may accelerate carbonate pedogenesis.It addresses the agricultural implications of IPCC recommended management practices like reduced tillage on SOC stabilization incalcareous soils, by 3) experimentally quantifying the influence of soil disturbance on carbonate pedogenesis and the fate ofmicrobially-mediated SOC storage. Finally, because reduced tillage requires greater mechanical weeding, a role which predominantlyfalls on women in rural drylands, the proposed MSCA considers gender disparity in labor when advocating best practices to increasesoil carbon. To achieve this, it 4) develops a scientifically robust training and support tool to empower and equip women for key rolesin agricultural management.