Jute plant purifies air
Jute has a high carbon dioxide (CO2) assimilation
power. Atmospheric CO2 is the most important of the
greenhouse gases responsible for global warming. Like all
plants, jute uses CO2 as a way of making sugars. In
the 100 days of the jute-growing period, one hectare of jute
plants can absorb about 15 MT of CO2 from atmosphere
and liberate about 11 MT of oxygen, the life-supporting agent.
Studies also reveal that the CO2 assimilation rate of
jute is several times higher than that of trees.
The environmental impacts of jute production are much less
harmful as compared to the production of synthetic fibers. Jute
growers use fairly small amount of chemical fertilisers and herbicides. Jute yields 5 -10 MT of dry matter per
acre of land. About 1 MT of dry matter is put back to the soil
in the form of leaves. About 3 MT of roots remain in the soil.
Jute cropping system enhances soil organic matter through leaf
shedding during the growing season and improves nutrient
availability in the soil.
Jute is commonly rotated with other food crops like rice and
other cereals, vegetables, oilseeds or pulses, all of which are
moderately or heavy feeders of nutrients from the native source,
but do not normally return them to soil, except in case of
legumes, as jute does. Jute-based multiple cropping thus not
only increases agricultural production, but may also sustain the
fertility level of soil mainly through leaf fall and organic
waste decomposition under jute, if the inputs throughout the
rotation are used judiciously.
Biological efficiency of jute
Jute is predominantly a rainfed annual crop
harvested at least once a year. Jute as a fibre crop is a
that takes only 4 to 5 months to mature. Unlike jute, the production of the fastest growing
wood plant necessitates at least 10 to 14 years from plantation
to harvest, and yields only 8 to 12 MT per hectare per annum.
This means the biological efficiency of jute or kenaf is much
higher than that of wood plants, and hence the usage of jute in
place of wood to make paper pulp will reduce the cost of
production to a large extent. It will also reduce the necessity
of cutting down of trees, i.e. deforestation .
In jute agriculture, use of fertilisers, pesticides and
weedicides/ fungicides is scanty. The extent of chemical
fertilisers for jute growing varies between 7-53 kg nutrient per
hectare. The quantity of fertiliser applied is so small that the
effect may be considered as insignificant. It should be noted
that jute plant sheds about 5-6 tons of green leaves per hectare
(i.e. ~14% of the crop) in the field. These green leaves left
out after harvesting are rich in macro- and micro-nutrients, and
act as manure for the subsequent crop in the field.
Gas emissions to the atmosphere
cultivation processes generate organic acids including acetone,
ethyl alcohol, butyl alcohol, and various gases like methane,
carbon dioxide (CO2) and hydrogen sulphide.
Substances that contribute to global warming in case of jute are
CO2 and methane. The latter one is released mainly
during retting under the traditional practice. Methane emitted
during retting has been estimated  to be 1-2 m3 kg-1
of solid material, which on computation gives an average of
1.428 kg methane per kg of jute fibre . It is known
that the global warming potential of methane is much
higher than that of CO2 and methane is more
detrimental as ozone depleting agent than CO2. Though
the contribution of methane under traditional retting towards
global warming is insignificant the improved method, say, ribbon
retting offers a significant advantage from this point of view.