Carbon loss from our soils - a double whammy

Carbon forms the biggest part of living and dead organisms and natural organic materials. Carbon in the form of carbon dioxide is removed from the atmosphere and converted to organic carbon through the process of photosynthesis. Carbon enters the soil in the form of organic material from flora and fauna. Soils are a major carbon reservoir containing more carbon than the atmosphere and terrestrial vegetation combined. Soil organic matter besides containing about 58% C is a storehouse of essential nutrients. It affects not just the fertility of soils but the entire suite of chemical and physical properties including, the soil structure, porosity, water  holding capacity and diversity of soil organisms, to name a few, and all of these are essential for healthy soils and ultimately food productivity. Organic matter runs the engines of life in soils. Organic matter or organic carbon has fundamental role in sustaining soil functions, loss of carbon therefore implies impairment of soil quality. Rising temperature causes soil to release more carbon dioxide. In the buzz about planetary climate change, storing carbon in soils and preventing efflux of carbon in the form of various gases to the atmosphere is the key issue. Kashmir being a temperate region has an advantage of storing higher amount of carbon in its soils than the hotter parts of India. But that shouldn’t make us think that global warming is not going to affect our soil carbon. It is declining in our soils too and the causes are many, hopefully some of them can be mitigated. Rise in global average temperature is going to affect the soils of temperate Kashmir more severely than it would affect the hotter regions. Because soils that hold the most carbon under current climate scenario also release the most carbon in response to warming. Warming of the planet is triggering its release into the atmosphere. Thus, our soil is a vulnerable resource. Rise of 1°C will result in the release of almost twice the amount of carbon emitted due to human activities annually. Thus, loss of carbon from our soil is a double whammy, it impairs soil productivity and deepens climate crisis.

The soil organic carbon content depends on the balance between the carbon input and output. Agriculture or for that matter soil can be a source or sink of carbon depending on management. For long our farming systems have mined the soil for nutrients and reduced soil organic matter/carbon levels through continuous harvesting of crops. This decline will continue and will be aggravated by rising temperature, until management practices are improved. Kashmir is witnessing unabated changes in land use. Our resource base is shrinking and shriveling. The ability of soils under forests, pastures, crops and wetlands to store carbon for long periods of time in declining. Many studies have demonstrated that soil organic carbon storage decreases with a shift from a natural land use pattern to an artificial land use pattern. It is this newly converted land which suffers the greatest losses of C during and subsequent to its conversion. Thus, impact of changes in land use and management on soil quality and cycling/storage of carbon cannot be overemphasized, particularly in the context of climate change and sustainability. Besides, the looming threat of climate change world over, in case of Kashmir particularly, erosion, overgrazing, tillage, construction and infrastructural development activities on erosion prone lands, lead to colossal loss of soil and carbon, with serious consequences on land and water resources as well as environmental quality.

Farm-level management of carbon to increase its level in soil and getting some mitigation of the climate crisis as spinoff is a value-proposition. By adoption of practices involving prevention of soil loss and enhancing carbon storage in soils, farmers can do their bit. Millions of tonnes of topsoil, rich in organic carbon and plant nutrients can be saved from washing away through adoption of measures like conservation tillage, vegetated bunds, terracing, run-off control, planting of multi-purpose trees and ensuring continuous vegetative cover. Indeed many of these practices form a part of a broader term now known as carbon farming. It is a process of changing agricultural practices or land use to increase the amount of carbon stored in the soil and vegetation. Many countries have conceptualized result-based carbon farming schemes which offer opportunities to directly incentivize farmers for undertaking climate-friendly actions. Payments are made to the land holders for avoiding green house gas emission or carbon sequestration while achieving multiple economic and environmental co-benefits. In Maharashtra carbon farming project was initiated with 20 farmers in two districts. The project, by contributions from individuals, private companies, and NGOs concerned about climate change, compensates farmers for increase in soil organic carbon through adoption of a form of zero-till conservation agriculture. The pilot project envisages to make a small contribution to the global goal of improving few million hectares of degraded and deforested land by the end of this year. Although the efforts like this is not a silver bullet that will solve the issue of climate change and soil degradation, however, it seems more promising than carbon trading which won’t work for agriculture.

Another important aspect of carbon conservation is the proper farm and urban waste management. To solve this problem of plenty what we need is a change of perspective. Burning and improper disposition of humongous quantities of agricultural wastes generated in the fields not only causes environmental pollution but also wastes a lot of valuable biomass carbon. The simplest process of biodegradable waste valorization is converting it into a carbon and nutrient rich manure through composting. By practicing simple measures like these farmers can return considerable amount of organic matter back to the soil making it more productive. The onus of saving environment, resource conservation and organic waste management doesn’t lie with the farmers only. The city and town folks incautiously discard lots of organic matter as garbage. More than half of what is thrown into garbage bins is biodegradable waste. With the kind of changes in our living standard and lifestyle, municipal solid waste collection and disposition is going to get more arduous. Waste segregation and backyard composting of your kitchen scraps, autumn leaves, twigs, grass trimmings etc., seems to be the most practical way to deal with it. Compost the compostable and use it to enrich soil.

Meanwhile, if your garden waste wasn’t picked up by garbage collector, don’t fume and trash his explanation, and pardon me if you find me siding with the garbage man in the argument. As someone has put it laconically, though in a somewhat different and more Kafkaesque context, that ‘in the fight between you and the world, back the world’.

Shakeel Mir is Asst Professor FoA  Wadura, SKUAST-KASHMIR. Views are author’s own, and not of the institutions he works at.