Expected effects of global warming on global agricultural production

a. Soil processes:

The potential for soils to support agriculture and distribution of land use will be influenced by changes in soil water balance: It increases in soil water deficits i.e. dry soils become drier, therefore increased need for irrigation but Could improve soil workability in wetter regions and diminish poaching and erosion risk

b. Crops

The effect of increased temperature and CO2 levels on arable crops will be broadly neutral:

• The range of current crops will move northward
• New crop varieties may need to be selected
• Horticultural crops are more susceptible to changing conditions than arable crops; (what happens to the high chilling requiring temperature fruits such as apple???)
• Field vegetables will be particularly affected by temperature changes
• Phaselous bean, onion and sweet corn are most likely to benefit commercially from higher temperatures
• Water deficits will directly affect fruit and vegetable production

 c. Grasslands and livestock

• There is unlikely to be a significant change in suitability of livestock.
• Pigs and poultry could be exposed to higher incidences of heat stress, thus influencing productivity
• Increase in disease transmission by faster growth rates of pathogens in the environment and more efficient and abundant vectors (such as insects)
• Consequences for food quality and storage

d. Weeds, pests and diseases:

• Weeds evolve rapidly to overcome control measures, short lived weeds and those that spread vegetatively (creeping buttercup, couch etc) evolve at the greatest rate.
• Rate of evolution will increase in hotter, drier conditions and in ‘extreme years’, could lead to some types of herbicide tolerance becoming more common
• Possible increase in the range of many native pests, and species that at present are not economically important may become so
• Surveillance and eradication processes for other significant pests, such as the Colarado beetle will become increasingly important