Straw Compost Cuts Fertilizer Cost
As farmers worry about how to manage their postharvest wastes, rice straw in particular, a study shows that these wastes, if properly managed, can lessen their problesm on high fertilizer cost in rice farming.
Just consider this: 5 tons (t) of rice straw can save 1-2 bags of urea, 2-3 bags of muriate of potash, and 1/2 bag of solophos.
RICE STRAW BURNING IS NOT GOOD
A harvest of 1 ton grain produces 1 t of rice straw. This gives us an idea of how much rice straw stays in the field after every harvest.
Many farmers usually burn their rice straw, thereby posing hazards to people and the environment, according to Engr. Rosanna Espiritu of the PhilRice Integrated Systems and Standards Office (ISSO). Rice straw burning generates air pollutants such as particulates, carbon monoxide, hydrocarbons, nitrogen oxide, and sulfur dioxide. It can also release airborne silica fibers or small particles of straw ash with possible carcinogenic health effects (source: http://calrice.org/).
Certain laws prohibit the practice of open-field burning like the Republic Act 9003 or the Ecological Solid Waste Management Act and Republic Act 8479 or the Clean Air Act. These laws have been imposed for us to have a safe and clean environment to live in and for the protection of our nature.
WHAT THE SURVEY SAYS
Interestingly, a team of researchers led by Ronnel B. Malasa of PhilRice Socioeconomics Division studied the awareness and technology adoption of rice straw composting by our farmers. A total of 1,451 farmers from at least 30 rice-producing provinces of the country were the respondents of the study covering the 2007 dry season.
The study showed that more farmers were aware of the technology (65%) but more than half of thos~ who were aware still practiced rice straw burning. Generally, the survey showed that 15% of the farmers used rice straw as fertilizer, 46% burned their rice straw, 13% burned and used rice straw as fertilizer, and 26% of them neither used the rice straw as fertilizer nor burned it. Farmers who don’t burn their rice straw leave it in the field or incorporate it in the soil to serve as additional fertilizer for the soil, while some use it as fodder for their farm animals.
COMPOSTING MADE EASY
Given the irreversible effects of rice straw burning, PhilRice has been practicing and promoting rice straw composting. Since rice straw contains some of the nutrients that the plants need, they are being used as organic fertilizer through in situ composting.
A study by Rizal G. Corales on farm biomass recovery system shows that rice straw composting or straw incorporation can improve soil fertility, reduce the need of chemical fertilizers, and increase yields to some extent. Based on the study, composting can be prepared in two ways. One is in situ composting and the other one is rapid process composting.
In situ composting of rice straw is done with the use of EMBI or effective microorganism microbial inoculant with the EM activated solution. It is applied in the rice straw after spreading it in the field during land preparation at a rate of 500 kg/ha and 5 L/ha, respectively.
On the other hand, rapid composting is made with the use of CFA or compost fungus activator like Trichoderma sp. At a rate of 400 g/kg material, CFA is added with 100g Azotobacter sp. and with EMBI at 100 g/kg material. The materials used in this study were rice straw (30 kg), grasses (2.5 kg), and chicken manure (7.5kg). Composting was done in a mesh wire bin covered with plastic sack.
SAVE ON FERTILIZER COST
With the skyrocketing prices of fertilizers, farmers must know how to produce their own organic fertilizers.
Due to this, PhilRice, through the efforts of ISSO and other divisions like the Technology Management and Services Division, provides technical briefings and trainings on the different technologies involving organic fertilizer to agricultural technicians and other partners in promoting environment friendly and sustainable agriculture.