Attached
A preliminary survey was conducted at three integrated farming systems to determine the
effect of long term (>25 years) crop-livestock integration on some soil and plant properties
and composition. Herbage of grazed coconut land consisted of 90.6% grasses, 5.7%
legumes and 3.7% other species where Carpet grass .(Axonopus compresses) was the
dominant species. The species diversity of the natural herbage of un grazed coconut land
was high representing 36.78% grasses, 29.86% legumes and 36.32% other species having
more erect type plant species with Narrow Leaf Carpet grass CA. affinis; dominating. Long
term grazing effect resulted to promote dominating prostate type plant species such as
Carpet grass (Axonopus compresses), Heen undupiyaliya iDesmodium trifolium) due to
super imposed grazing pressure.
The effect of buffalo grazing the natural herbage growing 111 a coconut plantation was
examined in an experiment of 6 months along with the survey. The Dry Weight Rank
Method (OWRM) which gives an accurate estimate of the plant composition (PC) of
grassland on dry weight basis, without the necessity of cutting and hand separating (HS)
samples was used in estimating the Pc. The OWRM was tested 5 times by comparing
results with those of HS samples. With each of the five tests conducted, the rk increased
from 0.1348 to 0.8922 indicating greater ability to accurately predict HS data using the
simple DWRM observations. For all observations 1'2 was 0.65 (p<O.05) giving a positive
correlation and that regression was used to predict HS using OWRM data to study the PC of
the herbage. PC of natural herbage under short term grazing indicated that as there was
selective grazing and the ability to withstand grazing differed between species, with the
time of grazing prostate type plant species dominated. At any time of the grazing. Heen
undupiyaliya tDesmodium trifolium) and Narrow-leaf carpet grass iAxonopus a/finis)
presented more than 10% of the herbage and significant (p<0.05) indicating that short term
grazing enhances the growth of prostate type plants.
Comparatively Dry matter (OM) and Organic matter (OM) yields or the herbage in each
harvest were low in grazed herbage compared with the ungrazed herbage in both dry and
wet seasons. Significantly (p<0.05) highest OM and OM yields were recorded in ungrazed treatment during wet season. Due to selective grazing of more palatable herbage and over
maturity of remaining plant species, Crude Protein (CP%) of grazed herbage was
significantly low ( p<O.05) than in un grazed herbage.
Soils collected from long term integrated farming sites had a significantly higher (p<O.05)
average pH of (5.58) as compared to that of non integrated sites (4.65). Reduction or acidity
may be due to the improvement of soil nutrients via dung, urine and also due to
accumulation of litter. Also it was visually observed that the soil in integrated sites were
dark in colour as compared to non integrated soil due to the same reason. Bulk density of
integrated soil (l.15 g/crrr') was comparatively lower with that of non integrated soil (1.4 g/
crrr'). Although not significantly (p<O;05), the moisture content improved in grazing
coconut land due to improved ground cover as compared with ungrazed soil specially
during wet season. Significant improvement was not observed because of the overriding
effect of the shade of coconut trees facilitating the retention of moisture under both
conditions. Similarly soil porosity also improved due to integration. Even though the effect
of long term grazing improved physical properties of soil, short term grazing effect has not
changed the same as such.
Overall results suggest that the waste materials such as excreta, beddings, dairy washings
and residues of feeding materials thus produce various benefits with passage of time
showing potential for the sustainability of a crop- livestock systems and also buffaloes can
be introduced to weedy coconut plantations as environmentally friendly biological loan
movers for better sustainability.
