Category Archives: Ermelinda Dias

System of Rice Intensification: Win-win solution

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For resource-poor farmers of Goa, who are also battling changes in weather, the system of rice intensification has come as a boon.  Goaded by the State Agriculture Department and supported by the Indian Council of Agricultural Research, some farmers adopted this low-tech, low-cost approach for raising yields, and have been pleasantly surprised by the results.  The State Govt has decided to upscale the pilots to cover the entire state this year.

Rice is staple food for majority of Indians, and for resource-poor farmers, it is a major source of both income and calories.But rice is a water-intensive crop and a source of methane emissions.  A kg of rice cultivated on irrigated land requires not less than 3000-5000 ltrs of water, and continuous flooding required for its cultivation  proliferates methane-emitting anaerobic bacteria which thrive in oxygen-depleted soils caused by flooding.  In a globalised and urbanised world, with increasing population and changing diets, water-stress and unprecedented weather changes like extreme rain events, changing monsoon patterns & changing season durations, a system of rice cultivation which is input-reducing and yield enhancing is welcome to farmers.

System of Rice Intensification (SRI)  is based on the understanding that rice is not an acquatic plant and that continuous submergence under water does not allow it to reach its yield potential.  SRI  improves productivity by changing the management of plants, soil, water and nutrients and involves transplantation of very young single seedlings in widely spaced square pattern  instead of  older ones transplanted randomly in bunches  as in the traditional method.  The single and wide-spaced transplantation encourages greater root growth and wider canopy development.

The soil has to be kept moist, but well drained with sufficient organic matter to support biological activity says Satish Tendulkar,Director of Agriculture, Goa.  Thus instead of flooding, a minimum water is applied during the vegetative growth period, and thereafter a thin layer (1-2 cm) is maintained during the flowering and grain-filling period.  Weeds which is a problem in fields not kept flooded,  are handled through simple mechanical hand-held push-weeders, which also assists soil-aeration, and enhances soil-fertility by letting weeds decompose in the soil.  Farmer Ganesh Dessai says he has not used much chemical fertilizers, but relied on compost and organic manure to get the enhanced yields.

“Techniques are difficult to disseminate because they require trained extension workers says B. Vijjain, Chief Secretary of Goa, who has successfully introduced SRI to farmers in Pondicherry, and at whose instance the Agriculture Dept first introduced SRI  to farmers in Goa during 2009-2010. Since then  several blocks across talukas like Sanguem, Bardez, Tiswadi & Sattari have been adopted as pilots and have registered enhanced yields by more than 35%.  Extensive demonstrations are going on throughout the state to rope in as many farmers as possible and bring the whole state under SRI.

Says V.  Gaonkar, SRI specialist in ICAR, Ela, Goa, “SRI benefits include 50-100 % higher yields, about 50% water savings and upto 90% savings on seeds.  Better soil aeration, better soil biotics through compost and organic manure and wider spacing allows individual plants to grow strong roots and send out more tillers.  Instead of conventional 20-30 tillers, SRI sends out upto 100 with each bearing 250-500 grains as agianst 100 or so in the traditional method.

First  developed in 1980s by Fr. Henri de Laulanie in Madagascar for improving crop yields of poor farmers, SRI has become popular around the world and used in over 28 countries including China, Laos, Cambodia, Vietnam, Indonesia, etc.  This veritable revolution which can address world food crisis and climate-change related problems like reduced agricultural productivity & increasing water stress has been driven by NGOs &  progressive farmers.  On the other hand it has faced resistance from established rice research institutions like IRRI, Manila.  According to Achim Dobermann, Head of Research, IRRI, ” the claims are grossly exaggerated and cannot be verified due to lack of sufficient data”.  Prof. Norman Utholf, Cornell University, however says that ” farmers have missed this method for centuries, and scientists have missed it till recently while some are still in denial mode”

SRI offers significant benefits with strong climate change implications – reduced methane emissions, reduced water requirements and reduced use of nitrogenous fertilizers.  Since SRI does away with continuous flooding of fields, methane emissions will be significantly reduced.  Since rice fields consume more than 70% of irrigated water, the huge water savings under SRI will reduce water demand and positively impact ground water exploitation and dipping water-tables.  Similarly since around 20% of nitrogenous fertilizers are consumed by rice cultivation, there would be significant reduction in use of fertilizers since SRI works best with compost and organic manure.  It can also help the state in dismantling economically problematic subsidies on fertilizers, electricity and water-usage.

Clearly SRI is a win-win- situation.  It can address food security, improve farmers’ adaptability to climate change, help agricultural sustainablity and also help mitigation process. It is time governments around the world and agricultural academia join hands with farmers to centre-throne this revolution.

Jellyfish Blooms: Comment on Health of our Seas

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For last few weeks beaches in Goa have been inundated with jellyfish causing inconvenience to tourists and hardships to fishermen.  While jellyfish is important component of the oceanic environment, their proliferation is linked to changing chemistry of the seas.  Though most jellyfish species are harmful, some have irritating and even venomous stings which threaten to turn our beaches into no-go areas.

Jellyfish blooms have been observed on many beaches and coasts around the world specially Japan, Australia, Mexico, England, Scotland, Israel, etc.  Recently jellyfish blooms clogged electric power stations in England & Scotland, while in Japan two nuclear reactors had to be temporarily stopped due to the arrest of their cooling systems which were supplied by sea water.  Jellyfish blooms can play havoc with coastal desalination plants and disable ocean freighters.  Commercial fishing industry in Japan has been badly affected by ‘nomurai’ species of jellyfish.

Jellyfish require warm and saline water to thrive and normally they spend most of their lives in the open seas.  Researches say that they approach the beaches only when the coastal water which is colder and less saline stops acting as a barrier to their approach.  This happens in many places where less and less fresh water from rivers is entering the seas due to droughts, dams and coastal constructions like ports, etc.  Environmental experts link frequent jellyfish blooms over the last few years to human induced environmental stresses like habitat modification, overfishing, eutophication and climate change.  Researchers say that global warming and warmer waters accelerate jellyfish growth, while overfishing of natural predators like sharks and bluefin tuna helps their proliferation.

Jellyfish have very high tolerance to oceanic environmental damage says Dr. Baban Ingole, Chief Scientist in Biological Oceanography at Panaji-based National Institute of Oceanography. While many fish varieties are either killed or are driven away by changing habitats, jellyfish can survive in damaged environments, he adds. According to an UNEP Report, acidification of oceans due to increased carbon emissions makes it difficult for corals and shellfish to make skeletons, which drives away many fish varieties depending on them for food.  Since the Industrial Revolution acidity levels of the oceans have increased substantially because oceans absorb more than 30% of atmospheric carbon emissions. Decline in creatures with shells could trigger an explosion of jellyfish as they are more immune to acidification.

Jellyfish is attracted to polluted waters and is a strong indicator of ocean health.  According to Dr. Nandakumar Kamat, Professor of Biology at Goa University, nitrification of the oceans due to fertilizer run-off and eutophication following discharge of untreated sewage into water bodies tend to favour jellyfish proliferation.  Jellyfish are ‘scavengers’ of the ocean and survive in the oxygen-depleted ‘dead zones’ typically found near coastal cities.  Dr. Nandakumar says because  most organisms do not survive the ‘dead zones’, jellyfish face lesser or no competition for food, rather they thrive on the debris of ‘dead zones’

Researchers say that it is difficult to predict how much the worldwide population of jellyfish would increase, but do warn that if the proliferation continues, it would certainly affect fisheries and tourism sector badly.  Fishing industries in Japan, Gulf of Mexico, Mediterranean Sea have already been affected, and local fishermen are complaining of lesser catch during periods of beach invasion by jellyfish.

To the extent that jellyfish blooms are caused by global warming and increased acidification of the seas, any action taken to fight climate change like use of renewable energies would help in management of jellyfish blooms.Steps needs to be taken to reduce pollution of rivers and seas and curb dumping of untreaated sewage and hazardous chemicals into water bodies.  Reducing fertilizer run-off through use of natural manure and biological pesticide would certainly help.  It is necessary to curb overfishing through fishing regulations so that damaged habitats are restored and natural balance among different species of fish is maintained.  Periods of fishing bans should be strictly executed.

 

 

 

 

Jellyfish require warm and saline water to thrive and normally they spend most of their lives in the open seas where the water is warmer and more saline.  Researches say that they approach the beaches only when the coastal water which is colder and less saline stops acting as a barrier to their approach.  This happens in places where less and less water enters the seas from the rivers due to droughts, dams or coastal construction like ports, etc.  Environmental experts link frequent jellyfish blooms over last few years to human induced environmental stress like habitat modification,