Agriculture along with land use change, is an important source of climate change, and contributes to 31 percent of anthropogenic greenhouse gas (GHG) emissions, mostly in developing countries. BMZ-GIZ program on ‘Soil protection and rehabilitation for food security’ as part of Germany’s special initiative “One world – no hunger” has been pushing the climate-smart agriculture approach aimed at transforming agricultural systems to sustain food security under climate change while also limiting GHG emissions.
A recent study by International Center for Tropical Agriculture, Nairobi and Wageningen University titled ‘Rapid climate smartness assessment of GIZ soil protection and rehabilitation technologies’ in four sub-Saharan countries and India evaluates these technologies in terms of their potential impact on productivity, nitrogen balances, erosion, and GHG emissions. Per the study, these are suitable (rapid) indicators representing the three climate-smart agriculture pillars – food security, resilience and mitigation.
The rapid assessment study has a couple of insights for India, whose agriculture is characterised by declining farm holding size, soil erosion and loss of soil fertility affecting crop productivity and food security with climate change likely to exacerbate the issue. Dry areas, such as the state of Maharashtra, are especially vulnerable.
Four farm types were identified for case studies – dryland famers, the dryland diversified farmers, the rice farmers and the specialized irrigation farmers. “The rice farm sticks out in terms of poor climate-smart agriculture performance, which is mainly due to some farm-specific peculiarities… Specialized irrigation farms are usually better off, have specialized in the production of high-value crops, and thus, even though they are not producing large amounts of calories themselves, are certainly in a position to purchase food if required,” as per the study.
The study indicates that adding up calories produced from the various crops and livestock products and comparing business-as-usual with best-bets, is however a simple and easy-to-grasp way of indicating changes. “Focusing on soil fertility and erosion as the resilience indicator excludes a large number of important issues that contribute to farmers’ resilience to climate change, such as income stability, access to skills, finances and information, crop/livestock diversity, etc.”
An important insight from the study was that “productivity increases may come at the cost of nutrient mining, if not carefully planned. Appropriate measures for replacing extracted nutrient need to be adopted that take into account the current state of the soil. Intercropping with N-fixing legumes alone is not enough to narrow negative N balances, but supplementation of organic and inorganic fertilizers is often required. In India, balances are (very) positive because of such high use of inorganic fertilizers. This is another concern because of possible environmental damages. In such cases we must be cautious when promoting interventions that will further increase the N balance and rather look into interventions that will “replace” the N provided by inorganic fertilizers while providing other benefits/functions to soil health.
Livestock keeping, paddy rice and residue burning are largest contributors to GHG emissions, depending on the country and farm type. The study underlines the need “for improving the integration of livestock into farms through better manure management, as well as improved feeds and forages, husbandry and health care to improve livestock productivity and hence decrease emission intensities.”
Paddy rice (India) is an important contributor to GHG emissions in some farm types. An alternative residue management would be first entry points to decrease GHG quantities. Alternating wetting and drying cycles as part of a System of Rice Intensification (SRI) is the most promising technology to lower methane emissions from rice, safe water while maintaining or even increasing yields.
The study underlines the importance of careful targeting of technologies to farming systems to ensure sustainable intensification. True triple-win climate-smart solutions, i.e. interventions that increase productivity, improve resilience and reduce GHG emissions, are rare. Instead, implementing soil conservation and rehabilitation measures often has a positive impact on just one or two of the climate-smart agriculture but a negative effect on the remainder(s); i.e. trade-offs have to be made. None of the proposed technologies addresses climate change mitigation (reducing GHG emissions from agriculture) directly.