PAPER PRESENTED AT INTERNATIONAL WORKSHOP ON INCREASING WHEAT YIELD POTENTIAL, CIMMYT, OBREGON, MEXICO, 20–24 MARCH 2006 Conservation agriculture: what is it and why is it important for future sustainable food production?

Abstract

Conservation agriculture (CA), defined as minimal soil disturbance (no-till) and permanent soil cover (mulch) combined with rotations, is a more sustainable cultivation system for the future than those presently practised. The present paper first introduces the reasons for tillage in agriculture and discusses how this age-old agricultural practice is responsible for the degradation of natural resources and soils. The paper goes on to introduce conservation tillage (CT), a minimum tillage and surface mulch practice that was developed in response to the severe wind erosion caused by mouldboard tillage of grasslands and referred to as the American dust bowl of the 1930s. CT is then compared with CA, a suggested improvement on CT, where no-till, mulch, and rotations significantly improve soil properties (physical, biological, and chemical) and other biotic factors, enabling more efficient use of natural resources. CA can improve agriculture through improvement in water infiltration and reducing erosion, improving soil surface aggregates, reducing compaction through promotion of biological tillage, increasing surface soil organic matter and carbon content, moderating soil temperatures, and suppressing weeds. CA also helps reduce costs of production, saves time, increases yield through more timely planting, reduces diseases and pests through stimulation of biological diversity, and reduces greenhouse gas emissions. Availability of suitable equipment is a major constraint to successful CA, but advances in design and manufacture of seed drills by local manufacturers are enabling farmers to experiment and accept this technology in many parts of the world. Estimates of farmer adoption of CA are close to 100 million ha in 2005, indicating that farmers are convinced of the benefits of this technology. The paper concludes that agriculture in the next decade will have to produce more food, sustainably, from less land through more efficient use of natural resources and with minimal impact on the environment in order to meet growing population demands. This will be a significant challenge for agricultural scientists, extension personnel, and farmers. Promoting and adopting CA management systems can help meet this complex goal.

Econometric Analysis of the Factors that Affect Adoption of Conservation Farming Practices by Smallholder Farmers in Zambia

“…This may be true because of the time lags between when benefits kick start and when the smallholder farmer decides to adopt CF packages. Such time lapses can affect the smallholder farmers' propensity to adopt CF as observed by Hobbs (2007). Kassie et al (2012) also found that household's participation in at least one rural institution or group and extension support from skilled civil servants is significant in adoption of CF practices because of increased chance of interaction and access to quality knowledge among farmers.…”

“…In this study, an adopter of CF was considered as the household that practiced at least any of the three main practices of CF which include minimum tillage, residue retention and leguminous crop rotations (Haggblade & Tembo, 2003;FAO, 2006;Hobbs, 2007;CFU, 2007;Simpson & Weamert, 2007). The choice of the variables that were hypothesized to affect adoption decisions of CF was based on the regularity with which a variable was cited in the literature.…”

“…Typically, CF involves the practice of dry-season land preparation, minimum tillage, crop residue retention, and nitrogen-fixing crop rotations (Haggblade & Tembo, 2003;FAO, 2006;Hobbs, 2007;CFU, 2007;Simpson & Weamert, 2007). CF practices in Zambia date back to the late 1980s and early 1990s (Haggblade & Tembo, 2003).…”

“…Despite continued efforts to promote adoption of CF in most developing countries, the adoption rate has been low (Fowler & Rockstrom, 2001;Derpsch, 2003;Hobbs, 2007). For example, it is estimated that about 10 percent of the smallholder farmers adopt some form of CF practices in Zambia (Haggblade & Tembo, 2003;CFU, 2005).…”

Tillage does not increase nitrous oxide emissions under dryland canola (Brassica napus L.) in a semiarid environment of south-eastern Australia

“…No-till farming has been widely adopted for dryland grain production in Australia due to benefits including improved soil structure with better water infiltration and water retention, increased ground cover with less soil erosion and increased soil fertility with more soil organic carbon sequestered (Chan and Heenan 2005;Hobbs 2007; Thomas et al 2007). In addition, the adoption of no-till farming reduces energy, machinery and labour inputs (Scott et al 2013), hence increasing on-farm profitability (Williams et al 1990).…”