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European chestnut (Castanea sativa Mill.) covers in total 2.53 million hectares, of which 2.2 million hectares are forests and the remaining parts, are orchards. In Europe it is growing in an area comprised by 27o N and 53o N latitude, from sea level in seaside regions to 2000 m above sea level (a.s.l.) in the south of Europe. According to Fernandez-Lopez et al. (2005), chestnut species is characterized by the existence of some differentiation among extreme populations, which can be supposed due to its long-range distribution across the Mediterranean region, through varying climatic conditions. As reported by Heiniger (1992), chestnut is a good indicator of warm regions with oceanic climate. In spite of C. sativa Mill. be characterized as a mesophilic species, nowadays the chestnut shows many growth limitations, which partially can be ascribed to the climate changes, since they influence abiotic and biotic factors and consequently photosynthetic productivity. From abiotic factors, water and heat stress have been the most important limitations, inducing less growth, less vigor increasing susceptibility to the biotic factors such as ink and blight diseases. When compared with other hardwood species, the trees can absorb the same amount of carbon, but due to the fast-growing chestnut can store more carbon in less time. So, this agro forest system has been identified as an important way to slow climate change. Photosynthesis, according to (Givnish, 1988), provides green plants with almost all of their chemical energy, being central to their activity to compete and reproduce. So understanding |
