The global distribution of Earth's critical zone and its controlling factors

Abstract The delicate interplay of various Earth’s systems processes in the Critical Zone is vital in ensuring an equilibrium across the different spheres of life. The upper crust forms a thin veneer on the Earth’s surface that is defined by an interconnected network of brittle structures. These brittle structures enable various Earth System processes. Increased anthropogenic interactions within the very upper crust have seemingly resulted in a growing number of negative natural effects, including induced seismicity, mine water drainage and land degradation. Brittle structures across South Africa are investigated. These structures include various fractures and dykes of different ages and geodynamic evolutions. The orientation of these structures is compared to the underlying tectonic domains and their bounding suture zones. The orientations corroborate an apparent link between the formation of the brittle structures and the tectonic evolution of the southern African crust. Reactivation and the creation of new structures are also apparent. These are linked to the variability of the surrounding stress field and are shown to have promoted magmatism, e.g., Large Igneous Provinces, and the movement of hydrothermal fluids. These fluids were commonly responsible for the formation of important mineral deposits. The preferred structural orientations and their relationship to underlying tectonic zones are also linked to fractured groundwater aquifers. Subsurface groundwater displays a link to structural orientations. This comparison is extended to surficial water movement. Surface water movement also highlights an apparent link to brittle structures. The apparent correlation between these Earth’s systems processes and the interconnectivity developed by brittle structures are clear. This highlights the importance of high-resolution geological and structural mapping and linking this to further development of the Earth’s Critical Zone.

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Connecting Modern Soil and Paleosol Communities: Improving Climate Proxies and Our Understanding of Earth's Critical Zone

CSA News ◽

10.2134/csa2014-59-10-10 ◽

2014 ◽

Vol 59 (10) ◽

pp. 24-25

Author(s):

Steven G. Driese ◽

Michael H. Young ◽

Eric C. Brevik

Keyword(s):

Critical Zone ◽

Modern Soil ◽

Climate Proxies ◽

Earth’S Critical Zone

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Soil organic carbon dynamics and controlling factors in typical ecosystems of the Qinghai-Tibet Platea critical zone

10.5194/egusphere-egu2020-20806 ◽

2020 ◽

Author(s):

Hongyun Yao ◽

Pei Wang ◽

Chao Yang ◽

Xuebao Xu ◽

Junqi Wei ◽

...

Keyword(s):

Organic Carbon ◽

Environmental Changes ◽

Stable Carbon Isotope ◽

Soil Surface ◽

Carbon Dynamics ◽

Critical Zone ◽

Controlling Factors ◽

Desert Ecosystem ◽

Tibet Plateau ◽

Critical Zones

The interface of the Earth&#8217;s critical zone is the place where organic carbon is dramatically decomposed and transformed&#65294;The dynamics and fate of organic carbon serve as an important foundation to reveal the material transportation in the Qinghai-Tibet Platea critical zones. This research analyzed temperature, soil moisture and stable carbon isotope values (&#948;13C) of CO2 in different soil layers, measure soil surface respiration using soil respiration measurement system (LI-8100) , and analyzed carbon storage , carbon dynamics and its controlling factors in critical zones in seven typical ecosystems of the Qinghai-Tibet Platea. The results found that the underground carbon content and its controlling factors were very different in different ecosystems on the Qinghai-Tibet Plateau. The main controlling factor of carbon changes was water in alpine steppe and desert ecosystem while it was temperature in alpine meadow. In the meanwhile, this research also measured the maximum carboxylation rate (Vcmax) of dominant plants in each ecosystem, trying to explore the different carbon inputs in different ecosystems. Understanding the impacts of environmental changes on the geochemical cycling of critical zone&#8217;s organic carbon in the Qinghai-Tibet Platea would benefit the optimization of carbon cycling model and climate change predictions&#65294;

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The Earth’s Critical Zone Science and its Research Progress

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.2138 ◽

2013 ◽

Vol 295-298 ◽

pp. 2138-2142

Author(s):

Wei Hua Zhang ◽

Yan Yang ◽

Jun Ying Jin

Keyword(s):

Critical Zone ◽

Research Progress ◽

Biological Processes ◽

Climatic Anthropogenic ◽

Interdisciplinary Concept ◽

Earth’S Critical Zone ◽

Tectonic Forcing

A promising and involving interdisciplinary concept-the earth’s critical zone science is introduced in this paper. Within the earth’s Critical Zone, the coupled chemical, physical and biological processes which define Earth’s weathering engine are driven by climatic, anthropogenic, and tectonic forcing. Followed by the concept and specific questions related to the critical zone were given. Finally, current research in order to understand the Critical zone was reviewed.

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A New Focus on the Neglected Carbonate Critical Zone

Eos ◽

10.1029/2021eo163388 ◽

2021 ◽

Vol 102 ◽

Author(s):

Jonathan Martin ◽

Paloma De Grammont ◽

Matthew Covington ◽

Laura Toran

Keyword(s):

Critical Zone ◽

Earth’S Critical Zone

Studies of Earth’s critical zone have largely focused on areas underlain by silicate bedrock, leaving gaps in our understanding of widespread and vital carbonate-dominated landscapes.

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