Agrotechnology

Changes in soil carbon content in a chronosequence of transformation from cocoa to pastureland in Southeast Mexico

13^th International Conference on Agriculture & Horticulture

September 10-12, 2018 | Zurich, Switzerland

Eduardo Valdes Velarde, Rufo Sanchez Hernandez, Sergio R Marquez Berber and Abdul Khalil Gardezi

Chapingo Autonomous University, Mexico
Juarez Autonomous University of Tabasco, Mexico
Postgraduate College in Agriculture Science, Mexico

Scientific Tracks Abstracts: Agrotechnology

Abstract:

Statement of the Problem: The cocoa agroforestry system (CAS) is one of the most important in the state of Tabasco, Mexico. The CAS can store quantities of carbon (C), even higher than some natural forests. Under humid tropics conditions, the size of the soil organic matter (SOM) stores is small and rapidly degrades, so that soil fertility can be quickly depleted making the agroecosystem highly dependent on the supply of fertilizers. Objectives: The objective of this research was to measure the concentration of soil organic carbon (SOC) and other variables indicating soil fertility, in a chronosequence of pastures that were established on cocoa plantations. Methodology & Theoretical Orientation: The research was carried out at Jalpa de Méndez, Tabasco, Mexico. Sites that were previously CAS were selected and that currently record a change in land use. With the years of change reported by farmers, the following intervals were established: 1-5 years (PZ 1-5), 6-10 years (PZ 6-10) and 11-20 years (PZ 11-20). At each site samples were taken at three depths (0-10 cm, 10-20 cm and 20-30 cm). Results: The results indicate that during the first years, the land use changed (PZ 1-5) given a slight decrease in the levels of SOC. Although these increase in the pastures of 6-10 years (PZ 6-10), inclusive above the levels recorded in CAS 20-35. However, this increase is temporary, since it is observed that these storage levels decrease in pastures 11-20 years (PZ 11-20). In the long term, the change of land use from CAS to pasture reduces the SOC stores and some chemical and physical properties. In the first years of the change the reduction of the SOC content is reflected in the young pastures (PZ 1-5). In older pastures (PZ 11-20) the chemical and physical properties declined and the content of the SOC decreases to level below CAS 20-35. Recent Publications 1. Bautista Mora E (2016) Use of wooden and non woody forest resources of the cacao agroforestry systems (Theobroma cacao L.) Agroproductivity. 9(2):50-55. 2. Cheng Man and Shao Shan An (2015) Responses of soil nitrogen, phosphorous and organic matter to vegetation succession on the Loess plateau of China. J. Arid Land. 7(2):216???223. 3. Diaz Jose O et al. (2013) Current state of and perspectives on cocoa production in Mexico. Cien. Inv. Agr. 40(2):279-289. 4. Don A, Schumacher J and Freibauer A (2011) Impact of tropical land???use change on soil organic carbon stocks: a metaanalysis. Global Change Biology. 17(4):1658-1670. 5. Schroth G et al. (2015) Contribution of agroforests to landscape carbon storage. Mitigation and Adaptation Strategies for Global Change 20:1175-1190.

Biography :

Eduardo Valdés Velarde is a Professor of Ecology in the Department of Plant Science of Chapingo Autonomous University in Mexico since 2007. He is currently the Director of the Agroforestry Center for Sustainable Development at the same university. He has been a Teacher of high school, undergraduate and graduate students since 1997, lecturing more than 25 subjects. He has been the Director and thesis Adviser for more than 25 undergraduate and graduate students. He has given numerous lectures and courses-workshops in several universities in Mexico and Ecuador. He has been responsible for several research, cultural diffusion, service and technology transfer projects. His main lines of research focuses on the study of ecosystem services in mangroves, cacao and coffee plantations.

E-mail: velarde@correo.chapingo.mx