Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecos...Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecosystem in terms of water and nutrient uptake. In this study the effects of thinning and litter fall removal on fine root production and soil organic carbon content were examined in 20-year-old Masson pine （Pinus resinosa） plantations in Huitong, Hunan Province of China in the growing seasons of 2004 and 2005. The results showed that fine root production was significantly lower in the thinning plots than in the control plots, with a decrease of 58% and 14% in 2004 and 2005 growing seasons, respectively. Litter fall removal significantly increased fine root production by 14% in 2004. Soil temperature （Tsoil） and soil moisture （Msoil） were higher in the thinning plots than those in the controls. Litter fall removal had significant effects on Tsoil and Msoil. Soil organic carbon content was higher in the thinning plots but was lower in the plots with litter fall removal compared with that in the controls. Our results also indicated that annual production of fine roots resulted in small carbon accumulation in the upper layers of the soil, and removal of tree by thinning resulted in a significant increase of carbon storage in Masson pine plantations.展开更多
After the Second World War of the past century in Italy extended plantations were carried out. In Southern Italy the Calabrian pine （Pinus laricio Poiret） has been the most used species, for its ability to take root...After the Second World War of the past century in Italy extended plantations were carried out. In Southern Italy the Calabrian pine （Pinus laricio Poiret） has been the most used species, for its ability to take root in many difficult conditions. Currently the extension of this vegetation is about 36,000 hectares, in great part established in Calabria. They have reduced hydrogeological risks, they have carried out an important social role and have improved the landscape and the environment of huge hill and mountain territories. After the realization of these stands, no forest management has been made in order to define purposes and silvicultural operations. All stands are currently vulnerable in order to abiotic （fire, breakages） and biotic （Traumatocampa （--- Thaumetopoea） pityocampa （Denis ＆ Schiff.） and Heterobasidion annosum （Fr.） Bref.） agents. For the future, the silvicultural management of these stands will not be able to avoid planning choices, in order to improve the structural stability and the bioecological functionality and to consider the recent opportunities offered from the agroenergetic field.展开更多
In Italy, the hydro-geological protection of the Apennine territories is a well-known issue. For this reason, at the end of the 19th century, a new reforestation technique was proposed by the Inspector of Forest Servi...In Italy, the hydro-geological protection of the Apennine territories is a well-known issue. For this reason, at the end of the 19th century, a new reforestation technique was proposed by the Inspector of Forest Service, Pietro Montanari to cope with difficult soil conditions of the mountain areas. This new approach was the first application of the so-called ＂gradoni＂ （small terraces） method of soil preparation. Each ＂gradone＂ was 100-120 cm wide and made with a slight counter slope （ca 10-15 degrees） to promote the accumulation of water and organic matter. Along each ＂gradone＂, bare root black pine seedlings （Pinus nigra Am.） were planted at a distance of 1 m from each other with a density of more than 3,000/ha. Nowadays, 19,158 hectares of black pine forests are growing in the Apennine of the Abruzzi region, largely resulting from those reforestation projects realized since the beginning of the 20th century. A case study of Monte Plaia （42°00′ 12″ N 13°53′39″ E）, that illustrates the situation after 70-110 years in consequence of lacking of silvicultural treatment and the application of aforest restoration method is presented.展开更多
基金Supported by the "948" Grant of the National Forestry Administration of China (No.2007-4-19)the Special Grantof Chinese Forestry Public Benefits (Nos.200804030 and 2007-4-15)the Provincial Fund for Distinguished Young Scholars of Hunan, China (No.07JJ1004)
文摘Soils play a critical role in the global carbon cycle, and can be major source or sink of CO2 depending upon land use, vegetation type and soil management practices. Fine roots are important component of a forest ecosystem in terms of water and nutrient uptake. In this study the effects of thinning and litter fall removal on fine root production and soil organic carbon content were examined in 20-year-old Masson pine （Pinus resinosa） plantations in Huitong, Hunan Province of China in the growing seasons of 2004 and 2005. The results showed that fine root production was significantly lower in the thinning plots than in the control plots, with a decrease of 58% and 14% in 2004 and 2005 growing seasons, respectively. Litter fall removal significantly increased fine root production by 14% in 2004. Soil temperature （Tsoil） and soil moisture （Msoil） were higher in the thinning plots than those in the controls. Litter fall removal had significant effects on Tsoil and Msoil. Soil organic carbon content was higher in the thinning plots but was lower in the plots with litter fall removal compared with that in the controls. Our results also indicated that annual production of fine roots resulted in small carbon accumulation in the upper layers of the soil, and removal of tree by thinning resulted in a significant increase of carbon storage in Masson pine plantations.
文摘After the Second World War of the past century in Italy extended plantations were carried out. In Southern Italy the Calabrian pine （Pinus laricio Poiret） has been the most used species, for its ability to take root in many difficult conditions. Currently the extension of this vegetation is about 36,000 hectares, in great part established in Calabria. They have reduced hydrogeological risks, they have carried out an important social role and have improved the landscape and the environment of huge hill and mountain territories. After the realization of these stands, no forest management has been made in order to define purposes and silvicultural operations. All stands are currently vulnerable in order to abiotic （fire, breakages） and biotic （Traumatocampa （--- Thaumetopoea） pityocampa （Denis ＆ Schiff.） and Heterobasidion annosum （Fr.） Bref.） agents. For the future, the silvicultural management of these stands will not be able to avoid planning choices, in order to improve the structural stability and the bioecological functionality and to consider the recent opportunities offered from the agroenergetic field.
文摘In Italy, the hydro-geological protection of the Apennine territories is a well-known issue. For this reason, at the end of the 19th century, a new reforestation technique was proposed by the Inspector of Forest Service, Pietro Montanari to cope with difficult soil conditions of the mountain areas. This new approach was the first application of the so-called ＂gradoni＂ （small terraces） method of soil preparation. Each ＂gradone＂ was 100-120 cm wide and made with a slight counter slope （ca 10-15 degrees） to promote the accumulation of water and organic matter. Along each ＂gradone＂, bare root black pine seedlings （Pinus nigra Am.） were planted at a distance of 1 m from each other with a density of more than 3,000/ha. Nowadays, 19,158 hectares of black pine forests are growing in the Apennine of the Abruzzi region, largely resulting from those reforestation projects realized since the beginning of the 20th century. A case study of Monte Plaia （42°00′ 12″ N 13°53′39″ E）, that illustrates the situation after 70-110 years in consequence of lacking of silvicultural treatment and the application of aforest restoration method is presented.
