Agriculture Reference
In-Depth Information
Fig. 4.2
Vegetation showing morphology of
Ipomoea aquatica
China (Edie and Ho
1969
) (Fig.
4.2
). Besides, it is also been introduced in Hawaii,
Brazil, Cuba, Jamaica, Trimidad and other Islands of West Indies. It is widely dis-
tributed throughout tropical and warm climate regions of southeastern Asia. and
also been distributed in Arabia, western Africa, Egypt and India (Upendra and
Sinha
2001
)
It is a tropical trailing, habituating muddy stream banks but it is also found in
fresh water ponds and marshy areas (Jain et al.
1987
). The components of the plants
which are submerged showed some resistance to adverse or unfavorable conditions
(Chin and Fong
1978
). Vegetation formed by aquatic weeds provides support for
the luxurious growth of
I. aquatica
, which also grows on the borders of wet paddy
fields. The roots grow rapidly and hardly require any attention. Heavy clay, water
lodging and organic soil are ideal for its growth (Morton and Snyder (
1976
). Un-
like water hyacinth, it is suitable to spread and compete with native vegetation.
Growing seasonal productivity of
I. aquatica
marked upto 27.48 g m
−2
day
−1
and
extrapolated productivity upto 100.30 mt ha
−1
year
−1
was recorded by Kanungo
et al. (
2001
). It contains rich nutritional composition of moisture, crude oil, crude
fibre, carbohydrate, crude protein and mineral elements including K, Fe, Mn, Zn,
Na, Ca and Mg (Umar et al.
2007
).
4.3
Bio-decomposition of Aquatic Macrophytes
The decomposition of aquatic macrophytes as aquatic biomass residues involves
three fundamental steps which may occur simultaneously or after time layers, i.e.,
physical, autolytic and microbial leaching. The leaching of dissolved inorganic/or-
ganic matter through a biotic decomposition facilitates microbial colonization and
catabolism of the decaying litter due to depolymerization of structural materials
