2. 


Increase the in concentration of plant
nutrients in water bodies which result in
excessive
growth
of
certain
organism, depletion of dissolved 02 and
elimination of aerobic organism.
The process is slow and often reversible, but
anthropogenic activities have accelerated the
process through N & P input and diminished
the buffering capacity of the ecosystem.
The higher concentration of dissolved
nutrients in water promote rapid growth of
algea.

3. 

Point sources: refer to the water pollution
that originates from known or definite
sources such as discharge pipes of
wastewater form factory etc.
Non Point sources: originates from diffuse
sources and can not be traced to a single or
identifiable sources.

4. 
Soil mismanagement:
-
monocropping
crop residue removal
low vegetative cover
excessive tillage
row cropping

5. 
Soil characteristics
- low organic matter content
- steep slopes
- poor internal drainage
- high silt content
- low permeability
- low activity clays

6. 
Climate
- intense rains
- high runoff potential
- high wind velocity

7. 
Use of fertilizer and pesticide
- high rates of fertilizer application
- poor timing of chemical application
- poor selection of herbicide
- surface application of chemical
- high solubility of chemicals

8. 




Sediment
Nitrogen
Phosphorus
Animal manure
Pesticide

9. 


Water runoff
Leaching
Volatilization

10. 

Management of chemical input
Conservation practices
- vegetative cover
- crop rotations
- conservation tillage
- crop residue
- conservation buffer
- mechanical structure