zation of agricultural lands and study (Easterling, 1996; Watson etal., 1997):
•     Possibilities of extending crop productive agricultural lands to Siberia and northern Canada;
•     Optimal shift of perennial horticultural crops by opti­mizing the interactions between varieties, new cultiva­tion environment and crop management systems;
•     Occupation of the most sensitive regions (irregular rain­fall alternated with intense droughts) by plants that are more robust and have a high plasticity; and
•     New and changed species composition of forest areas and its consequence on the amount of forest biomass available.

This adaptation and preparation will be more robust if data have a higher degree of certainty than before, as with the data from IPCC used for predictions of climatic changes (IPCC, 2007).

Development of new and adapted agricultural practices and crop varieties. Simultaneous development of new varieties, ei­ther new crops or agricultural crops adapted for predicted cli­matic changes and agronomic practices appropriate for those crops under predicted climatic conditions may be required.
     Some of the desirable traits for these new varieties are better suited for high temperatures, with increased or stable growth with less water and and/or transient drought toler­ance, longer durations of vegetative growth and grain fill­ing periods, early budding and better frost resistance for orchard varieties and field crops (Seguin et al., 2006).
     Some practices include planting earlier so that crop de­velopment would be more advanced in the case of a summer drought, using longer-season cultivars, mixing cultivars and planting seeds deeper and harvesting earlier. Early plant­ing might also eliminate the necessity of artificial drying of grain. Soil moisture may be conserved by using conserva­tion tillage methods, modifying the farm microclimate for example by integrating trees as shelterbelts and changing the way irrigation, fertilization and crop-protective sprays are scheduled, so that inputs are applied according to crop needs or field conditions.
     A reevaluation and adjustment of these above mentioned options may prove to be useful, for example by taking into account new rhizosphere communities that develop due to climate change and the effect of these communities and their interactions with the surrounding agroecosystem.

Development of new social systems to enable smooth tran­sitions of rural economies and maintenance of world food supplies. Mass human migrations stimulated by scarcity are often highly disruptive and damaging. If global climate change undermines the basis for agricultural production in rural NAE, it may cause dust bowl-like migrations such as those that occurred in the US during the 1930s. New so­cial programs could be designed to face this scenario and to help alleviate rural poverty and facilitate the economic transformation of rural NAE. Ensuring a stable produc­tion of agricultural products so that world food supplies are maintained during these transitions could be one of the main goals of these programs.

6.2.2 Facing new and emerging human, livestock and plant diseases

6.2.2.1  Human and livestock diseases
The past few decades have seen an alarming increase in new and emerging diseases such as AIDS, BSE, SARS, avian influ­enza, foot and mouth disease and others. These diseases are seen as a threat to global animal, plant and human health. One reason for this upsurge is the increased exposure of humans to infectious agents through changes in lifestyle, international travel and industrialization and globalization of the food industry. However, adequate understanding of the root causes of this upsurge is still lacking. Clearly it will not be possible to meet development goals unless the AKST system responds to the challenge of emerging diseases.
AKST could be used to elucidate the following aspects for a better management of these diseases through the following:
•     Understanding the origin of new and emerging diseases
-     Differentiate between "new" and "emerging" dis­eases: some of these diseases may be old diseases with newly recognized etiologies. Others are dis­eases that did not exist more than 100 years ago. This difference is important to understand to be able to project the future occurrence of new and emerging diseases (Desenclos and de Valk, 2005);
-     Understand the ecological and evolutionary dimen­sions leading to the development of new and emerg­ing diseases.
•     Predicting epidemics and pandemics across both spatial and temporal scales
-     Identify factors that increase the risk of develop­ing infectious diseases: new areas of risk factor re­search include the relationship between changes in the environment (such as climate change) and the incidence and distribution of diseases; and the influ­ence of crop and livestock genetic makeup on their susceptibility to disease and response to treatment (Desenclos and de Valk, 2005);
-     Develop basic fundamental research about hosts, pathogens and their interactions at different levels (molecular, cellular and superior integrative levels) (Horwitz and Wilcox, 2005):
-    Hosts: physiopathology, immune response;
-    Pathogens: ecology and biology of the patho­gens, vectors; and
-    Host-pathogen interactions: cellular and mo­lecular mechanisms, evolutionary potential (de­velop a better understanding of how pathogens mutate and migrate and how they skip host species barriers) and in particular research on resistance to anti-infectious drugs.
•     Construct models for the system as a whole:
-     Multidisciplinary groups of scientists studying the ecology of an emerging infectious disease could help in the building of these models. These models are parameterized with data from field studies and pathological   and   microbiological   investigations. These studies enhance classic epidemiology by in­volving an array of medical, veterinary, health and