Deng Kai, Yang Shouye, Guo Yulong
State Key Laboratory of Marine Geology, Tongji University, 200092, Shanghai, China.
Institute of Geochemistry and Petrology, Department of Earth Sciences, ETH Zürich, Clausiusstrasse 25, 8092, Zürich, Switzerland.
Nat Commun. 2022 Apr 4;13(1):1781. doi: 10.1038/s41467-022-29415-0.
Silicate weathering as an important negative feedback can regulate the Earth's climate over time, but much debate concerns its response strength to each climatic factor and its evolution with land surface reorganisation. Such discrepancy arises from lacking weathering proxy validation and scarce quantitative paleo-constraints on individual forcing factors. Here we examine the catchment-scale link of silicate weathering intensity with various environmental parameters using a global compilation of modern sediment dataset (n = 3828). We show the primary control of temperature on silicate weathering given the monotonic increase of feldspar dissolution with it (0-30 °C), while controls of precipitation or topographic-lithological factors are regional and subordinate. We interpret the non-linear forcing of temperature on feldspar dissolution as depletion of more reactive plagioclase (relative to orthoclase) at higher temperature. Our results hint at stronger temperature-weathering feedback at lower surface temperature and support the hypothesis of increased land surface reactivity during the late Cenozoic cooling.
随着时间的推移,硅酸盐风化作为一种重要的负反馈机制可以调节地球气候,但关于其对每个气候因子的响应强度以及随地表重组的演化存在诸多争议。这种差异源于缺乏风化指标验证以及对各个驱动因素缺乏定量的古约束。在这里,我们使用一个全球现代沉积物数据集(n = 3828)的汇编来研究流域尺度上硅酸盐风化强度与各种环境参数之间的联系。我们发现,随着温度(0 - 30°C)升高,长石溶解单调增加,表明温度对硅酸盐风化起主要控制作用,而降水或地形 - 岩性因素的控制是区域性的且较为次要。我们将温度对长石溶解的非线性驱动解释为在较高温度下更具反应性的斜长石(相对于钾长石)的消耗。我们的结果暗示在较低地表温度下温度 - 风化反馈更强,并支持了新生代晚期冷却期间地表反应性增加的假说。