Fighting change

climate study

A study on the effects of climate change in Karnataka, done by the IISc, has projected the average rise in temperature to be between  1.8 and 2.2 degree Celsius by 2030, writes M N Kulkarni

Climate change will soon become a reality. The Indian Institute of Science, Bangalore, in its report “Climate variability and climate change projections – Karnataka Region 2011”, has projected the average rise in temperature between 1.8 and 2.2 degree Celsius by 2030.

Rise in temperature has been attributed to the burning of fossil fuels, charcoal, wood, forest fire, burning of garbage, weeds, agricultural residues, etc. These, in turn, are adding carbon dioxide and other greenhouse gases to the environment. Greenhouse gases like carbon dioxide, nitrous oxide, methane, etc., have the capacity to trap or absorb heat in sunlight and prevent it from escaping into space. The presence of these gases in the atmosphere beyond certain limits is the main reason for the increase in global temperature that leads to global warming. It has been estimated that the presence of carbon dioxide during the pre-industrial period was 280 ppm, and now, it has increased to 400 ppm.

The impact of climate change may vary from place to place — change in rainfall pattern, erratic rainfall, heavy downpour, heat waves, concurrent droughts, reduction in the crop yield, reduction in the evapotranspiration, etc. The State has been experiencing drought for the last two to three years.

Change in rainfall pattern

This year also, rainfall is not uniform in all areas of the State. One can also observe the change in the rainfall pattern. Earlier, there used to be good rains during June and July. Nowadays, farmers are required to wait till the end of August and September to complete sowing operations. There is also a decrease in the average number of rainy days.

In Karnataka, more that 60 per cent of land is under rain-fed conditions. Hence, the impact of climate change will be severe in dry lands. An increase in temperature by 1 degree Celsius would lead to 5 to 10 per cent reduction in the crop yield, and a rise in 2 degree Celsius may lead to heavy crop losses. Hence, adopting mitigation measures becomes inevitable in the changed scenario. Integrated farming system (IFS) plays an important role in mitigating climate change effects. The IFS includes a menu of low-cost, environment-friendly interventions like planting horticulture trees, forestry trees, fodder trees, fodder grasses, composting methods, natural methods for disease and pest management, dairy animals, small ruminants, soil and water conservation measures etc. In this practice, farmers are required to plant three to four fruit species (mango, tamarind, cashew, guava, etc) and eight to ten forestry species.

The fruit plants can be planted in the cropping field or they can also be aligned along the bunds. Depending on the land holding, farmers can plant 40 saplings per acre. Forestry plants can be planted all along the field bunds and boundary bunds. The forestry plants need to include fuel wood species like acacia, cassia, glyricidia; timber species like teak, silver oak, melia dubia, dalbergia, etc. Sesbania, erythrina, subabul and moringa are the trees that yield good quality fodder.

Forestry plants start producing biomass and fuel wood after the fourth year of planting. Biomass produced from forestry plants can be used as substrate for producing vermicompost and applied to the field. This helps to reduce the application of chemical fertilisers, thus reducing the emission of nitrous oxide to the atmosphere. Fodder trees would yield enough quantity fodder, thus sustaining dairy activity. There will be enough fuel wood production by the fifth year of plantation.

This will meet the fuel wood requirement of the family and reduce pressure on the forests. The fruit trees start bearing fruits from the fifth year of planting and would fetch income for farmers.

Thus, in a period of five to six years, dry lands under IFS will become diversified farms with increased food security, fodder availability and resilience from climate change effects.

It is found that soils under IFS or organic farming would harvest 733 to 3,000 kg or more carbon per hectare per year from the atmosphere. Increasing the sequestration of carbon in soils is a vital aspect of climate change mitigation. By increasing carbon absorption, IFS has a lower climate impact than modern agriculture. In Karnataka, many NGOs are engaged in the promotion of IFS. The BAIF Institute for Rural Development in Tiptur, Tumkur district, has implemented the IFS (also called tree-based farming) system in 21,852 acres involving 19,708 farmers in different districts.

Motivating farmers

The Agriculture, Man, Ecology (AME) based in Bangalore is involved in motivating farmers to adopt Low External Input Sustainable Agriculture (LEISA) practices. The Initiatives for Development Foundation (IDF) based in Kunigal is implementing IFS through a project called ‘Sujeevana’ in Kunigal and Gubbi taluks, Tumkur district. The Foundation for Ecological Security (FES) based in Chintamani, Kolar district, is engaged in the promotion of seed dibbling on barren hillocks and agro-forestry systems in private lands.

Many government-sponsored programmes are also supportive for mitigating climate change effects. The organic farming village project, supported by the Department of Agriculture, GoK, has resulted in bringing over 38,200 hectare under organic farming methods. It is a good sign that the GoK is thinking of extending this project to one village in the remaining hoblis in the state. Farmers do use alternatives like vermicompost, enriched compost, liquid fertilisers, organic urea and green manuring instead of chemical fertilisers. This directly helps in controlling the release of greenhouse gas, nitrous oxide, into the atmosphere. The Karnataka State Biofuel Development Board is promoting the plantation of biofuel species like pongamia, simaruba, madhuca, etc., through projects ‘Hasiru honnu’ and ‘Baradu bangara’.

Under ‘Baradu bangara’, biofuel plants have been planted on Gomala school and temple premises, wastelands and forest lands. ‘Hasiru honnu’ helps small farmers plant 100 biofuel plants. It is known that trees sequester carbon dioxide, apart from helping farmers and the environment. Hence, plantation of trees helps mitigate effects of climate change.