Long-term Conservation Tillage Can Rebuild Soil Organic Matter Levels in Sandy Soils: Conservation tillage management resulted in an additional 7600 pounds of organic matter per acre in the top 5 cm (2 in) of soil compared to conventional tillage management. Increased soil organic matter not only sequesters carbon, but it can also reduce runoff and erosion and improve water and nutrient retention for plant growth.
Row Crop, Small Grains
Temperate, Tropical, Semiarid
North America, Europe
Nitrogen, Phosphorus, Sediment
Conservation tillage is any method of soil cultivation that leaves the previous year's crop residue on fields before and after planting the next crop and uses a non-inversion tillage method. Conservation tillage systems are characterized by systems where at least 30% of the soil surface is covered with residue after planting the next crop. Tillage is reduced by replacing some tillage operations for weed control with herbicide applications or by using tillage equipment that helps maintain a good residue cover. Types of conservation tillage include strip tillage, ridge tillage, mulch tillage, and no-till. These practices help reduce erosion, transport of nutrient enriched sediment and particulate, and volume of runoff. Conservation tillage practices improve water infiltration, nutrient absorption to soil matrix, and stabilization of soil surface to impede wind and water erosion detachment and transport of nutrient enriched sediment and particulates. They also provide temporary nutrient sequestration in soil organic matter. 2
Conservation tillage systems save time and energy by reducing or eliminating tillage operations. However, they may require use of herbicides for weed control and they may require different planters compared to those used with plowed fields. Soil that maintains residue cover is slower to warm up in the spring and can delay germination.
Scalable to small farms?
See FAO websites: http://www.fao.org/ag/ca/3g.html and http://www.fao.org/docrep/003/y1730e/y1730e03.htm There have been many advances in appropriate technologies, but in some cases this practice could require considerable investments in implements and herbicides. No till has been adapted for small farmers in Africa and other locales through the use of specialized implements for planting.
1 "Documentation: Source Data, BMP Effectiveness Values." Chesapeake Assessment Scenario Tool. Web. 2013. http://casttool.org/Documentation.aspx .
2 Estimates of County-level Nitrogen and Phosphorus Data for Use in Modeling Pollutant Reduction Documentation for Scenario Builder Version 2.2." Chesapeake Bay. Dec. 2010. Web. May 2013. http://archive.chesapeakebay.net/pubs/SB_V22_Final_12_31_2010.pdf.;"Beneficial Management Practices: Environmental Manual for Crop Producers in Alberta." Alberta Agriculture and Rural Development. 2004. Web. Apr. 2014. http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex9483/$file/100_25-1.pdf?OpenElement