Showing posts with label Environment. Show all posts
Showing posts with label Environment. Show all posts

Sunday, May 24, 2015

Sal (Shorea Robusta) in Nepal

 Plant local name:

    Distribution and Description:

      The tree is native to Indian sub continent ranging south of the Himalaya from Myanmar in east to Nepal, India and Bangladesh. In Nepal it is mostly found in terai region from east to west, especially in the Churia range. There are many protected areas such as Chitwan national park, Bardia national park and Shukla phata wildlife reserve where there are dense forests of huge Sal trees. It is also found in the lower belt of the hilly region and inner terai.
         S. Robusta is a large, deciduous tree up to 50m tall and with a DBH at 5m, these are exceptional sizes, and under normal conditions, it attains a height of about 18-32 m and girths 1.5-2m.
         The leaves of shorea Robusta are simple, shiny, glabrous, about 10-25cm long and broadly oval at the base, with apex tapering into a long point, new leaves reddish, soon becoming delicate green, flowers yellowish-white, arranged in large terminal or axillary racemose panicles.
           Fruit at full size is about 1.3-1.5cm long and 1cm in diameter it is surrounded by segments of the calyx enlarged into 5 rather unequal wings.

 Importance in Nepal:
           The natural s. Robusta forests in the terai are the country’s main source of building timber, and in the valleys of the hill region are a valuable source of timber fuel wood and fodder. The timber weighs between 800kg/m^3 and 960kg/m^3. It is an excellent fuel wood, with an energy content at about 22,700 KJ/kg for the heartwood and 21,300KJ/kg for the sapwood.
           Sal oil or butter is used for cooking locally and used for soap up to 30%. Refined, modified fat is a substitute for cocoa butter and used in confectionery industry. Sal butter is used in manufacturing of edible ghee, paints and pigments, lubricants, auto oil, etc. Sal seed oil can be used economically for production of bio diesel.
         S. Robusta leaves are widely used for making leaf plate and cups for both home use and sale to sale plate factories.

Saturday, May 23, 2015

Vermicomposting in Nepal


     Vermicomposting is the process of composting using various worms, usually Red wrigglers, White worms and other Earthworms to create a heterogeneous mixture of decomposing vegetable or food waste, bedding material and vermicast.

  Suitable species

      The most suitable species most often used for composting is the red wriggler (fisenia fetida or eisenia Andrei and lumbricus rubellus).other species used are:
1) Perionyx excavates
2) Eudrilus euginae
3) Lampito mauritii


1)      For vermicomposting a large variety of bins are commercially available, or a variety of adapted containers may be used. They may be made of old plastic containers, wood or metal containers. The design of a bin usually depends on where an individual wishes to store the bin and how they wish to feed the worm. Bins need holes for aeration.
2)      The most common worms used in composting systems, red worms feed most rapidly at temperatures of 15-25 degree Celsius. They can survive at 10 degree Celsius. Temperature above 30 degree Celsius may harm them. If worm bin is kept outside, it should be placed in a sheltered position away from the direct sunlight and insulated against frost in winter. Green waste can be added in moderation to avoid heating of bin.
3)      The worms at first should be left to get acclimated to the bin for about a week and after that we may begin to add waste. One pound of red worms can eat half a pound of waste daily, which translate to 3 to 4 pounds each week.
4)      Materials you can compost include fruit and vegetable peels, skins and cores, egg shells rinsed off to remove inner residues; used coffee grounds; and used tea bags; grains such as bread, cracker and cereals. The compost gets ready in 3 months.


1)      Never compost meat because it will turn rancid and smell and can promote the growth of harmful bacteria.
2)      Red worms should be used in vermicomposting instead of earthworms because the conditions inside the bin are too hot for earthworms to survive.


1) Soil

a) The compost improves soil aeration.
b) It enriches soil with micro organisms.
c) It improves water holding capacity.
d) Microbial activity in worm castings is 10 to 20 times higher than in soil and organic matter that the worm ingests.
e) Vermicompost attracts deep-burrowing earthworms present in soil.

2) Solid waste management

a) It reduces waste flow to landfills in huge quantity and thus promotes solid waste management.
b) Elimination of bio wastes from the waste stream reduces contamination of other recyclables collected in a single bin.
c) Vermicomposting makes use of waste material both in urban as well as rural areas to improve sanitary conditions.
d) It manages 70-75% waste in solid form.

3) Economic benefits

a) It creates low skill jobs at local level.
b) Low capital investment and relatively simple technologies male vermicomposting practical for less developed agricultural regions.
c) Effective replacement of chemical fertilizers.
d) produces high quality compost (8-10 times better than conventional compost)
e) It does not make use of electricity/energy.
f) Locally available materials can be used, which costs less. It means vermicomposting can be done on low investment.

4) Vermicast is completely biodegradable.
5)It is user friendly, even handicapped person can do.

6) It is environment friendly as it does not pollute or degrade the environment rather it preserves the environment to a greater extent.