Aeolian Processes and the Biosphere

Abstract

[1] Aeolian processes affect the biosphere in a wide variety of contexts, including landform evolution, biogeochemical cycles, regional climate, human health, and desertification. Collectively, research on aeolian processes and the biosphere is developing rapidly in many diverse and specialized areas, but integration of these recent advances is needed to better address management issues and to set future research priorities. Here we review recent literature on aeolian processes and their interactions with the biosphere, focusing on (1) geography of dust emissions, (2) impacts, interactions, and feedbacks, (3) drivers of dust emissions, and (4) methodological approaches. Geographically, dust emissions are highly spatially variable but also provide connectivity at global scales between sources and effects, with "hot spots" being of particular concern. Recent research reveals that aeolian processes have impacts, interactions, and feedbacks at a variety of scales, including large-scale dust transport and global biogeochemical cycles, climate mediated interactions between atmospheric dust and ecosystems, impacts on human health, impacts on agriculture, and interactions between aeolian processes and dryland vegetation. Aeolian dust emissions are driven largely by, in addition to climate, a combination of soil properties, soil moisture, vegetation and roughness, biological and physical crusts, and disturbances. Aeolian research methods span laboratory and field techniques, modeling, and remote sensing. Together these integrated perspectives on aeolian processes and the biosphere provide insights into management options and aid in identifying research priorities, both of which are increasingly important given that global climate models predict an increase in aridity in many dryland systems of the world.

Total vertical sediment flux and PM10 emissions from disturbed Chihuahuan Desert surfaces

“…This lack of increased post-fire TVSF production in the desert grassland treatment plots contrasts with most of the published literature (e.g. Ravi et al, 2011). It is possible that the dominance of the bunch grasses affected the post fire sediment transport or that the sandy texture of the surface affected this lack of fire effects as suggested by Sankey et al (2009).…”

“…The protective effect of vegetation is so great that grasslands in semi-arid and even some arid environments are essentially stable landscapes until some form of disturbance removes the vegetation. Disturbances to vegetation in arid and semi-arid environments often lead to land degradation and decreased environmental quality and appear to be happening with increased frequency (Breshears et al, 2003;Field et al, 2010;Ravi et al, 2011).…”

Long-term macronutrient stoichiometry of UK ombrotrophic peatlands

“…Such a mechanism, essential to maintaining productivity in ombrotrophic peatlands, is certainly in operation but may not be the only factor since human activities have increased the throughput of both N and P at regional and global scales since industrialisation (Neff et al, 2008). Gorham and Janssens (2005) observed progressive depletion of P (and N) content with distance from the cultivated Midwest, and attribute this to transport of nutrients as a component of windblown dust (Neff et al, 2008;Ravi et al, 2011;Van Pelt and Zobeck, 2007). Cheesman et al (2012) demonstrate that P availability decreases along a transect from a swamp-rimmed ombrotrophic wetland in Panama towards its centre, consistent with declining lateral supply (Tipping et al, 2014) with distance from neighbouring forest ecosystems.…”

Soil organic matter dynamics: a biological perspective derived from the use of compound‐specific isotopes studies

“…However, human impacts on factors such as land use, which is considered to be the most import human impact on earth, and climate change, decreases the ability of soils to grow plants and to sequester carbon (Canadell et al 2007;Lobell et al 2011;van der Molen et al 2011). The biggest climatic impacts on soils include extreme climate events (Jentsch et al 2007;Garcia-Herrera et al 2010), desertification (Lal 2010;Ravi et al 2011) and soil erosion (Poesen and Hooke 1997;Nearing et al 2004;Lal et al 2011). Our knowledge on the reactivity of the fragile surface of our planet, however, is still very limited and soils remain the largest single uncertainty in the global carbon cycle (Canadell et al 2007).…”