Location: Plant Science ResearchTitle: Carbon and nitrogen stocks of a typic acrudox under different land use systems Author
|Paulino, Valdinei - Sao Paulo State University (UNESP)|
|Neto, Siqueira - Sao Paulo State University (UNESP)|
|Teixeira, E.m.l.c. - Sao Paulo State University (UNESP)|
|Duarte, K.m.r. - Sao Paulo State University (UNESP)|
Submitted to: American Journal of Plant Sciences
Publication Type: Review Article
Publication Acceptance Date: 8/4/2014
Publication Date: 10/10/2014
Citation: Paulino, V.T., Neto, S.M., Teixeira, E., Duarte, K., Franzluebbers, A.J. 2014. Carbon and nitrogen stocks of a typic acrudox under different land use systems. American Journal of Plant Sciences. 2:192-200.
Interpretive Summary: Pasture degradation in Brazil is of global concern, especially in recognition of the previous land use as tropical forest. In the state of São Paulo, pasture degradation has occurred due to continuous grazing that limits plant vigor and regrowth potential. A group of scientists from the Institute of Animal Science, University of São Paulo, and the USDA-Agricultural Research Service reported on the changes in soil organic matter after 7 years under different land uses. Conventional tillage cropping had the lowest soil organic matter content, as expected. Integrated crop-livestock systems with maize undersown with different species and varieties of palisade grass (Urochloa spp.) had greater soil organic matter contents than continuation of perennial pasture under similar sward composition. These results will be beneficial to producers in Brazil to adopt better management approaches to optimize productivity and mitigate negative consequences to the environment.
Technical Abstract: Soil organic matter affects physical, chemical and biological conditions, and has been used as a soil quality index to differentiate the effects of different land uses and management practices. The objective of this study was to evaluate soil stocks of C and N under different land uses (conventional-tillage cropping, integrated crop-livestock system, and permanent pasture). The study area was located at the Institute of Animal Science in the municipality of Nova Odessa, São Paulo state (Brazil), with soil classified as Typic Acrudox with medium texture. Land use systems were: (1) integrated crop-livestock with maize and Urochloa brizantha cv. Marandu; (2) integrated crop-livestock with maize and U. ruziziensis; (3) integrated crop-livestock with maize and U. brizantha cv. Piatã; (4) long-term (25-yr-old) pasture with U. brizantha; and (5) conventional-tillage cropping with– maize only. The results showed that (to the layer 0-40 cm depth) the integrated crop-livestock systems (ICLS) had greater soil organic C (52.4 Mg ha-1) and N (4.3 Mg ha-1) than cropping (46.5 Mg C ha-1 and 4.0 Mg N ha-1) only or pasture only (47.6 Mg C ha-1 and 3.9 Mg N ha-1). The rotation with U. brizantha cv. Piatã had lower soil organic C (48.5 Mg ha-1) and N (3.9 Mg ha-1) than with U. brizantha cv. Marandu (56.2 Mg C ha-1 and 4.5 Mg N ha-1) and U. ruziziensis (56.6 Mg C ha-1 and 4.6 Mg N ha-1). These results suggest that integrated crop-livestock systems can be used to improve soil organic matter, and may have additional benefits in sustaining agricultural production in areas experiencing degradation from continuously grazed pastures.