Special Correspondent
Panaji
Stating that the adoption of soil and water technologies developed by it has helped reduce soil erosion loss and improve soil health in Goa, the Indian Council of Agricultural Research (ICAR) – Central Coastal Agricultural Research Institute (CCARI), Goa on Wednesday said that the state is characterised by its unique undulated topography where the slope of the land varies from 0% to 280% with an average slope of 14.41%.
“Goa also receives excess rainfall of more than 3,000 mm per year, and the soil erosion losses in the state vary from moderate (< 15 t/hectare/year) to extremely severe (> 80 t/hectare/year) classes, while the national average soil loss in India is 15.59 t/ha/year,” the ICAR-CCARI, Goa informed, pointing out that the permissible soil loss limit for India is 11.2 t/ha/year and the cultivation of crops like cashew, mango and coconut helps to reduce erosion losses as compared to fallow or barren lands.
The ICAR-CCARI, Goa has issued this statement in response to the media reports based on the information given by the Union Minister of Agriculture and Farmers Welfare Narendra Singh Tomar to an un-starred question asked by the Member of Parliament in Rajya Sabha Luizinho Faleiro on soil health management studies in Goa.
“Based on over 15-year studies conducted at ICAR-CCARI, Goa, soil erosion losses in cashew, mango and coconut cropping systems were estimated to be 24, 12.6 and 10.5 t/hectare/year, respectively without any conservation practices,” the ICAR-CCARI, Goa informed, adding that the soil erosion losses in these cropping systems are less or close to the national average soil loss.
“To further reduce the soil and nutrient loss, ICAR-CCARI, Goa has developed technologies for soil and water conservation measures in important crops of Goa like cashew, mango and coconut based on the long-term studies conducted,” the statement revealed, adding that the studies on cashew were conducted on 19% slope, during 2001-2013.
The statement also informed that in cashew, the soil and water conservation measure standardised (continuous contour trenching + vegetative barrier of vetiver grass) reduced the runoff by 44.5%, soil loss by 47% (reduced from 24 t/hectare/year to 12.3 t/hectare/year) and NPK loss by 60.2% (reduced from 89.7 kg/hectare/year to 35.7 kg/hectare/year) with increased soil organic carbon stock by 140%.
“Litter fall in cashew which starts during November-December covers the soil surface and acts as a physical barrier to runoff and reduces soil erosion losses, and further, the leaf litter helps to develop a conducive environment for micro-flora and fauna such as earthworms,” the ICAR-CCARI, Goa stated, noting that the improved organic matter and microbial activities lead to an increased infiltration rate. “This will result in improved soil moisture conservation and groundwater recharge,” it added.
“The studies on mango were conducted on 19% slope during 2002-2019, and in mango, a soil and water conservation measure of continuous contour trenching + vegetative barrier of vetiver grass (CCT+VB) reduced soil loss by 83% (reduced from 12.6 t/hectare to 2.15 t/ha) and runoff by 53% than control (reduced from 42.1% to 22.3%),” the statement informed, adding that this recommended measure on an average reduced NPK loss by 88.6% over control.
“Studies on coconut were conducted on 14% slope during 2008-2019, and in coconut, circular trenching reduced soil loss and runoff by 76% and 34%, respectively, which has reduced the NPK loss by 78.2% over control,” it revealed, adding that the cultivation of crops like cashew, mango and coconut reduces soil erosion, however adoption of soil and water technologies developed by ICAR-CCARI further help to reduce soil erosion loss and improve soil health.
The Union agriculture ministry had informed the Rajya Sabha earlier this week that ICAR-National Bureau of Soil Survey and Land Use Planning has prepared land resource inventory of Goa and found that Pernem and Bicholim talukas have extremely severe potential soil loses, accounting for 4.1% area of the state.