Poverty, risk, and the supply of soil carbon sequestration

2008 ◽  
Vol 13 (3) ◽  
pp. 353-373 ◽  
Author(s):  
JOSHUA GRAFF-ZIVIN ◽  
LESLIE LIPPER

ABSTRACTWe explore poor farmers' incentives to adopt production systems that increase soil carbon sequestration, focusing on the impact of risk. A dynamic optimization model of conservation agriculture adoption is presented, where farmers optimize over expected utility of profits from agriculture and carbon sequestration. Adoption impacts on agricultural productivity are modeled as a combination of the technological effects of the new system, and productivity effects of changes in soil carbon on agricultural output. Comparative static results indicate increases in soil carbon sequestration price and the discount rate have unambiguous impacts on equilibrium soil carbon levels; the former leading to higher, and the latter to lower, carbon levels. Increases in the price of agricultural output and risk aversion have ambiguous impacts, depending on the relative strength of the productivity and technology effects. The paper concludes with a discussion of designing soil carbon payment mechanisms to benefit low income farmers.

2018 ◽  
Author(s):  
Talal Darwish ◽  
Therese Atallah ◽  
Ali Fadel

Abstract. North East North Africa (NENA) region spans over 14 % of the total surface of the Earth and hosts 10 % of its population. Soils of the NENA region are mostly highly vulnerable to degradation, and food security will depend much on sustainable agricultural measures. Weather variability, drought and depleting vegetation are dominant causes of the decline in soil organic carbon (SOC). In this work the situation of SOC was studied, using a land capability model and soil mapping. The land capability model showed that most NENA countries (17 out of 20), suffer from low productive lands (> 80 %). Stocks of SOC were mapped (1 : 5 Million) in topsoils (0–30 cm) and subsoils (30–100 cm). The maps showed that 69 % of soil resources present a stock of SOC below the threshold of 30 t ha−1. The stocks varied between ≈ 10 t ha−1 in shrublands and 60 t ha−1 for evergreen forests. Highest stocks were found in forests, irrigated crops, mixed orchards and saline flooded vegetation. The stocks of SIC were higher than those of SOC. In subsoils, the SIC ranged between 25 and 450 t ha−1, against 20 to 45 t ha−1 for SOC. This paper also highlights the modest contribution of NENA region to global SOC stock in the topsoil not exceeding 4.1 %. The paper also discusses agricultural practices that are favorable to carbon sequestration. Practices of conservation agriculture could be effective, as the presence of soil cover reduces the evaporation, water and wind erosions. Further, the introduction of legumes, as part of a cereal-legume rotation, and the application of nitrogen fertilizers to the cereal, caused a notable increase of SOC after 10 years. The effects of crop rotations on SOC are related to the amounts of above and belowground biomass produced and retained in the system. Some knowledge gaps exist especially in aspects related to the effect of irrigation on SOC, and on SIC at the level of soil profile and soil landscape. Still, major constraints facing soil carbon sequestration are policy relevant and socio-economic in nature, rather than scientific.


2009 ◽  
Vol 28 (3) ◽  
pp. 97-122 ◽  
Author(s):  
B. Govaerts∗ ◽  
N. Verhulst∗ ◽  
A. Castellanos-Navarrete ◽  
K. D. Sayre ◽  
J. Dixon ◽  
...  

Geoderma ◽  
2020 ◽  
Vol 369 ◽  
pp. 114298 ◽  
Author(s):  
Elena Valkama ◽  
Gulya Kunypiyaeva ◽  
Rauan Zhapayev ◽  
Muratbek Karabayev ◽  
Erbol Zhusupbekov ◽  
...  

SOIL ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 225-235 ◽  
Author(s):  
Talal Darwish ◽  
Thérèse Atallah ◽  
Ali Fadel

Abstract. The Near East North Africa (NENA) region spans over 14 % of the total surface of the Earth and hosts 10 % of its population. Soils of the NENA region are mostly highly vulnerable to degradation, and future food security will much depend on sustainable agricultural measures. Weather variability, drought and depleting vegetation are dominant causes of the decline in soil organic carbon (SOC). In this work the status of SOC was studied, using a land capability model and soil mapping. The land capability model showed that most NENA countries and territories (17 out of 20) suffer from low productive lands (> 80 %). Stocks of SOC were mapped (1:5 000 000) in topsoils (0–0.30 m) and subsoils (0.30–1 m). The maps showed that 69 % of soil resources are shown to have a stock of SOC below the threshold of 30 tons ha−1. The stocks varied between ≈10 tons ha−1 in shrublands and 60 tons ha−1 for evergreen forests. Highest stocks were found in forests, irrigated crops, mixed orchards and saline flooded vegetation. The stocks of soil inorganic carbon (SIC) were higher than those of SOC. In subsoils, the SIC ranged between 25 and 450 tons ha−1, against 20 to 45 tons ha−1 for SOC. Results highlight the contribution of the NENA region to global SOC stock in the topsoil (4.1 %). The paper also discusses agricultural practices that are favorable to carbon sequestration such as organic amendment, no till or minimum tillage, crop rotation and mulching and the constraints caused by geomorphological and climatic conditions. The effects of crop rotations on SOC are related to the amounts of above and belowground biomass produced and retained in the system. Some knowledge gaps exist, especially in aspects related to the impact of climate change and effect of irrigation on SOC, and on SIC at the level of the soil profile and soil landscape. Still, major constraints facing soil carbon sequestration are policy-relevant and socioeconomic in nature, rather than scientific.


2014 ◽  
Vol 487 ◽  
pp. 587-603 ◽  
Author(s):  
Ch. Srinivasarao ◽  
Rattan Lal ◽  
Sumanta Kundu ◽  
M.B.B. Prasad Babu ◽  
B. Venkateswarlu ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document