Details

Autor(en) / Beteiligte

• DOU, F.G.
• HONS, F.M.
• OCUMPAUGH, W.R.
• READ, J.C.
• HUSSEY, M.A.
• MUIR, J.P.

Titel

Soil Organic Carbon Pools Under Switchgrass Grown as a Bioenergy Crop Compared to Other Conventional Crops

Ist Teil von

• Pedosphere, 2013-08, Vol.23 (4), p.409-416

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2013

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Switchgrass （Panicum virgaturn L.） has been proposed as a sustainable bioenergy crop because of its high yield potential, adap- tation to marginal sites, and tolerance to water and nutrient limitations. A better understanding of the potential effects of biomass energy crop production practices on soil biological properties and organic matter dynamics is critical to its production. Our objective was to evaluate changes in C pools under a warm-season perennial switchgrass in different soils compared to typically-grown crops col- lected at College Station, Dallas, and Stephenville, TX in February 2001. Sampling depths were 0-5, 5-15, and 15-30 cm. Switchgrass increased soil organic C （SOC）, soil microbial biomass C （SMBC）, mineralizable C, and particulate organic matter C （POM-C） com- pared to conventional cropping systems. Soil C concentrations were in the order： long-term coastal bermudagrass [Cynodon dactylon （L.） Pers.] 〉 switchgrass or kleingrass （Panicum coloratura L.） planted in 1992 〉 switchgrass 1997 〉 conventional cropping systems. Soil C concentrations tended to increase with increasing clay content. Greater microbial biomass C followed the order of Dallas 〉 College Station 〉 Stephenville, and ranged from approximately 180 mg C kg-1 soil at Stephenville to 1 900 mg C kg-1 soil at Dallas. Particulate organic C was more sensitive than other fractions to management, increasing as much as 6-fold under long-term coastal bermudagrass compared to conventional cropping systems. Our study indicated that conversion of conventional cropping systems into switchgrass production can sequestrate more SOC and improve soil biological properties in the southern USA.