Re-thinking the conservation of carbon, water and soil: a different perspective

Abstract

Sustaining soil productivity requires continuing actions of soil organisms on organic materials for optimizing of soil porosity and of movements of roots, water and gases in the root-zone. Soil is more quickly formed and self-renewed from the top downwards than only by slow additions from the bottom upwards. Loss of porosity diminishes soil's infiltration capacity and water-holding potential. Factors that provide insufficient organic substrates for soil organisms and that unduly accelerate oxidation of soil organic matter hinder the self-recuperation of soil and facilitate 'Stage-1' loss of carbon from within soil aggregates. They predispose the soil to lose rapidly even more carbon, in particulate form, through 'Stage-2' losses during consequent processes of runoff and erosion. Forms of land use and management are advocated that favor the functioning of soil-inhabiting organisms, including plants, such that carbon's capture in photosynthesis is increased, its usefulness in the soil as a rooting medium is prolonged, and its subsequent immobilization in the process of sequestration ameliorates the rate of increase in carbon dioxide concentration in the global atmosphere.

Participatory research and planning in practice

“…Adoption has also been slow due to the farmers' lack of access to the appropriate equipment (Hobbs 2007). Intercropping was challenging for European farmers because they lacked the information to select compatible cash crops (Shaxson 2006). Fourteen to 20 years may be required from the time that farmers became aware of a practice until its adoption (Corbeels et al 2014).…”

Increasing corn yield with no-till cropping systems: a case study in South Dakota

“…Ralph believes his next step of yield gain with corn and other crops will result from microbial benefits, as no-till and crop diversity favor the soil microbial community (Shaxson, 2006; Helgason et al, 2010). At a site 80 km north of the Holzwarth farm, a no-till system after 17 yr increased microbial biomass in soil almost 3-fold compared with a tilled rotation that included fallow (Liebig et al, 2004).…”

“…Integrating no-till with increased microbial biomass and diversity improves soil functioning (Auge, 2004; Shaxson, 2006). In one long-term (23 yr) study, small grains yielded 15% more in no-till than with a tilled system, even when adequate nutrients were available (LaFond et al, 2011).…”

Crop residue retention suppresses seedling emergence and biomass of winter and summer Australian weed species

“…CA and no-tillage systems are adopted on more than 52 million ha of Australian agriculture systems, which is more than 80% of the total cropping area (Llewellyn et al, 2016). Crop residue retention is an integral part of CA systems, providing ecological benefits such as reduced soil erosion, soil physiochemical characteristic improvement and soil microorganism activity enhancement (Govaerts et al, 2007;Sarkar & Singh, 2007;Shaxson, 2006). In such systems, weed seeds remain on the soil surface and seedling emergence is affected by crop residue retention during the growing season (Chauhan & Abugho, 2013;Chauhan & Mahajan, 2012).…”