Adaptation Strategies

For spring crops, climate warming will allow earlier planting or sowing than at present. Earlier planting in spring increases the length of the growing season; thus earlier planting using long season cultivars will increase yield potential, if soil moisture is adequate and the risk of heat stress is low. Otherwise, earlier planting combined with a short-season cultivar would give the best assurance of avoiding heat and water stresses (Tubiello et al., 2000). For winter crops (i.e. cereals), a specific growth stage has to be reached before the onset of winter to ensure winter survival, thus they are often sown when temperatures approach the time when vernalisation is most effective (Harrison et al., 1995b). This may mean later sowings in northern Europe under a climatic warming (Harrison et al., 2000; Olesen et al., 2000). A specific study reported by Wolf (2000b) of the effectiveness of changes in potato crop management (i.e. variety, planting date, irrigation) showed that in northern Europe the impact of the crop variety on the calculated change in irrigated tuber yield under the climatic change scenarios was nil, whereas in water-limited conditions, yield increases were larger for the earlier varieties. Cultivation of earlier varieties resulted in more positive or less negative tuber yield changes under the climatic change scenarios in Southern Europe, because the hot summer period was avoided, both with and without irrigation. Moreover, also an advanced planting date would determine higher yields. Finally, both an early crop variety and an earlier planting date would considerably reduce irrigation requirements.

Changes of land use may be used as adaptation strategies to the differential response of crops to climate change. Studies reported by Parry et al. (1988) for central Europe showed an "optimal land use" in which the area cultivated with winter wheat, maize and vegetables increased, while the allocation to spring-wheat, barley, and potato decreased. Changes in land allocation may also be used to stabilise production or for the conservation of soil moisture.

The introduction of optimal agricultural technology (machine, fertiliser, fungicide, etc.) may be considered as a fundamental strategy for adapting agriculture to climate change, especially in east Europe. A simulation study made by Sirotenko et al. (1997) for the entire Russia showed as the introduction of the present-day technological level could allow to overcome the negative impact of climate change on cereal production.

Changes in farming systems may be necessary in some areas for farming to remain viable and competitive. This will be true especially for those farms, specialised in either specific livestock or arable farming, that are often linked to the local soil and climatic conditions. Their responses will be probably more sensitive to climate change than mixed farms. On mixed farms with both livestock and arable production there are more options for change, and thus a larger resilience to change in the environment.

Some of the main adaptive measures for forest regions have been illustrated by Kellomaki (2000). These include shorter rotations and regular thinnings that in the Boreal and northern parts of Atlantic forests may be developed to meet the faster growth of several existing tree species, due to increasing precipitation and reducing drought. The regular thinnings will also increase the mechanical strength of trees due to enhanced growth and thus reduce the risk of abiotic damage.

In southern parts of the Atlantic forests, shorter rotation, regular thinnings with wider spacing, and more tolerant species (e.g. conifers) may be included to avoid the increasing drought risk, determined by the reduction of precipitation. Furthermore, the increasing fire risk requires special measures.

In the Continental and Mediterranean forests, soil management and planting techniques, that are presently adopted in dry sub-tropics climate, need to be developed to meet the special conditions caused by increasing drought. The impacts of drought may also be reduced through using wider spacing in plantations and later thinnings. The increase in fire risk will require special measures, especially in the Continental forests.

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