Abstract: |
Climate change, defi ned as any change in the average daily weather patt ern
over an extended period of ti me (typically decades or longer) whether
due to natural variability or as a result of human acti vity (Easterling et
al. 2007, IPCC 2007a), is happening now, and is already aff ecti ng many
natural systems around the world (IPCC 2007a).
The Intergovernmental Panel on Climate Change (IPCC) declared in its
Fourth Assessment Report (AR4) that climate change is unequivocal (IPCC
2007a), evidenced by observed changes in several global and regional
climati c indicators. The Food and Agriculture Organizati on (FAO) expects
that considerable eff orts would be required to prepare developing countries
to deal with climate-related impacts, parti cularly in agriculture (FAO 2007).
However, the IPCC also notes that recent studies show a high confi dence
that there are viable adaptati on opti ons that can be implemented at low
cost and/or with high benefi t-cost rati os (IPCC 2007a).
At the country level, climate change refers to observable changes and
permutati ons (undefi ned geographic variati ons) of temperature, rainfall
and extreme climate events and their single or collecti ve impacts on
various agricultural producti on and harvesti ng acti viti es (Concepcion
2008). Increase in temperature would have whole year and day-to-day
on-site impacts that accelerate the changes/decompositi on of soil organic
matt er and loss of soil ferti lity, which ulti mately aff ects the overall health
of crops and livestock. Soil temperature and organic matt er are useful
indices of ecosystem recovery aft er disturbance of natural vegetati on (Aust
and Lea 1991). The varying intensity and patt erns of rainfall and extreme
climate events (typhoons and El Niño) during the remaining periods of
rainy season would have expanded the coverage of climate change off -site
impacts which include massive soil erosion and irreversible loss of sloping
land soil ferti lity and life threatening fl oods and landslide (Concepcion
2008). |
|