The productivity of traditional agrisilviculture system(agricultural crops + trees) was investigated in the northern and southern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004?2...The productivity of traditional agrisilviculture system(agricultural crops + trees) was investigated in the northern and southern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004?2006.A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural system.The most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture system.The results show that the annual productivity of all tree species was 3 775 kg·ha-1·a-1 in northern aspect(site-N) and 3 101 kg·ha-1·a-1 in southern aspect(site-S).G.optiva had the highest productivity in both site-N and site-S among the tree species, followed by M.azedarach, Quercus leucotrichophora and C.australis.The dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the area.The average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture system.The sole agricultural crop productivity(without trees) in northern aspect was also higher than that in southern aspect.An obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern aspect.The overall productivity in traditional agrisilviculture system(crop + tree) was 24%(in northern aspect) and 21%(in southern aspect) higher than that in sole cropping system.展开更多
The productivity of traditional agrisilviculture system （agricultural crops ＋ trees） was investigated in the northern and south- ern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the ...The productivity of traditional agrisilviculture system （agricultural crops ＋ trees） was investigated in the northern and south- ern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004-2006. A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural system. The most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture system. The results show that the annual produc- tivity of all tree species was 3 775 kg.ha-1.a^-1 in northern aspect （site-N） and 3 10! kg.ha^-1.a^-1 in southern aspect （site-S）. G. optiva had the highest productivity in both site-N and site-S among the tree species, followed by M. azedarach, Quercus leucotrichophora and C. australis. The dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the area. The average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture system. The sole agricultural crop productivity （without trees） in northern aspect was also higher than that in southern aspect. An obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern aspect. The overall productivity in traditional agrisilviculture system （crop ＋ tree） was 24% （in northern aspect） and 21% （in southern aspect） higher than that in sole cropping system.展开更多
The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat metho...The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference.展开更多
This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L.from the subtropical conditions of western Himalaya.It ident...This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L.from the subtropical conditions of western Himalaya.It identifies the most accurate and convenient method for biomass calculation by comparing destructive with nondestructive methodology.Different parameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total aboveground biomass.Different explanatory variables were identified and measured such as basal diameter either as a single independent variable or in combination with plant height.The other suitable combinations of available independent variables include crown length,crown width,crown area,crown volume and coverage of the plant.Amongst the wide range of allometric equations used with different variables,the equation with D2 H as a variable was found to be the most suitable estimator of biomass calculation for Lantana.Sahastradhara,being the most disturbed area due to its high tourist activity round the year,showed maximum coverage（58.57 % ha-1）,highest biomass（13,559.60 kg ha-1） and carbon density（6,373.01 kg ha-1）of Lantana.The degree of Lantana’s invasiveness in subtropical conditions was also calculated on the basis of importance value index（IVI）.The maximum IVI（22.77）and mean coverage（26.8 % ha-1） was obtained from the areas near Jolly Grant airport,indicating that physically disturbed areas are more suitable for the growth of Lantana,which may significantly increase shrub biomass.The importance of incorporating allometric equations in calculation of shrub biomass,and its role in atmospheric carbon assimilation has thus been highlighted through the findings of this study.展开更多
文摘The productivity of traditional agrisilviculture system(agricultural crops + trees) was investigated in the northern and southern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004?2006.A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural system.The most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture system.The results show that the annual productivity of all tree species was 3 775 kg·ha-1·a-1 in northern aspect(site-N) and 3 101 kg·ha-1·a-1 in southern aspect(site-S).G.optiva had the highest productivity in both site-N and site-S among the tree species, followed by M.azedarach, Quercus leucotrichophora and C.australis.The dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the area.The average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture system.The sole agricultural crop productivity(without trees) in northern aspect was also higher than that in southern aspect.An obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern aspect.The overall productivity in traditional agrisilviculture system(crop + tree) was 24%(in northern aspect) and 21%(in southern aspect) higher than that in sole cropping system.
文摘The productivity of traditional agrisilviculture system （agricultural crops ＋ trees） was investigated in the northern and south- ern aspects of mid-hill situation in Garhwal Himalaya, Uttarakhand, India during the 2004-2006. A total of 19 tree species were studied in both northern and southern aspects, out of which 17 tree species were selected in northern aspect and 12 tree species in southern aspect for phytosociological characteristic analysis of trees in agrisilvicultural system. The most dominant tree species are Grewia optiva, Celtis australis and Melia azedarach and successively grown under traditional agrisilviculture system. The results show that the annual produc- tivity of all tree species was 3 775 kg.ha-1.a^-1 in northern aspect （site-N） and 3 10! kg.ha^-1.a^-1 in southern aspect （site-S）. G. optiva had the highest productivity in both site-N and site-S among the tree species, followed by M. azedarach, Quercus leucotrichophora and C. australis. The dominant agricultural crops were Eleusine coracana in summer cereals, Phaseolus vulgaris in summer pulses-oilseeds and Triticum aestivum in the winter season in the area. The average biological productivity of agricultural crops in northern aspect was about 16% higher than that in southern aspect under traditional agrisilviculture system. The sole agricultural crop productivity （without trees） in northern aspect was also higher than that in southern aspect. An obvious difference in annual productivity of trees and agriculture crops was observed between northern aspect and southern aspect. The overall productivity in traditional agrisilviculture system （crop ＋ tree） was 24% （in northern aspect） and 21% （in southern aspect） higher than that in sole cropping system.
文摘The natural regeneration of the tree species in pure natural forest stand and enrichment plantations of Baraitali Forest of Chittagong (South) Forest Division, Bangladesh was studied by stratified random quadrat method during April 2002 to November 2002. Totally 100 plots of 3 m X 3 m in size represents a total of 64 regenerating tree species from natural forest with an average seedlings of 24767/hm2, while only 40 regenerating tree species were recorded from enrichment plan-tations with an average seedlings of 18633/hm2. Maximum regeneration in natural forest was found with Castanopsis spp. (2200 seedlings/hm2) followed by Glochidion lanceolarium (2183 /hm2) whereas, in enrichment plantations maximum regen-eration was found with Dipterocarpus gracilis (2117/hm2) followed by Anogeissus acuminata (2000/hm2). For natural forest, highest relative density was found for Castanopsis spp (8.88%), relative frequency for Glochidion lanceolarium (7.36%), rela-tive abundance for Syzygium spp. (3.79%) and Importance Value Index were recorded with Glochidion lanceolarium (18.24%). The corresponding values for enrichment plantations were highest with Dipterocarpus gracilis (11.36%), Glochidion lanceo-larium (9.71%), Dipterocarpus gracilis (5.92%), Glochidion lanceolarium (23.32%) respectively. Stem per hectare of some common trees with their seedlings and saplings in both the natural stands and enrichment plantations showed that only Dip-terocarpus gracilis successfully recruited in both sites but recruitment was higher in natural forest. Like many other primary rain forests, the Baraitoli forest typically has both substantial seedlings and soil seed bank from which regeneration may occur. The naturally regenerated seedlings are quite dense but it could not reach the pole stage due to human interference.
文摘This study describes the different parameters used to derive the allometric equation for calculating the biomass of an invasive woody shrub Lantana camara L.from the subtropical conditions of western Himalaya.It identifies the most accurate and convenient method for biomass calculation by comparing destructive with nondestructive methodology.Different parameters were measured on a wide range of Lantana from different community levels for the non-destructive calculation of total aboveground biomass.Different explanatory variables were identified and measured such as basal diameter either as a single independent variable or in combination with plant height.The other suitable combinations of available independent variables include crown length,crown width,crown area,crown volume and coverage of the plant.Amongst the wide range of allometric equations used with different variables,the equation with D2 H as a variable was found to be the most suitable estimator of biomass calculation for Lantana.Sahastradhara,being the most disturbed area due to its high tourist activity round the year,showed maximum coverage（58.57 % ha-1）,highest biomass（13,559.60 kg ha-1） and carbon density（6,373.01 kg ha-1）of Lantana.The degree of Lantana’s invasiveness in subtropical conditions was also calculated on the basis of importance value index（IVI）.The maximum IVI（22.77）and mean coverage（26.8 % ha-1） was obtained from the areas near Jolly Grant airport,indicating that physically disturbed areas are more suitable for the growth of Lantana,which may significantly increase shrub biomass.The importance of incorporating allometric equations in calculation of shrub biomass,and its role in atmospheric carbon assimilation has thus been highlighted through the findings of this study.
