How to accurately simulate the distribution of forest species based upon their biological attributes has been a traditional biogeographical issue.Forest gap models are very useful tools for examining the dynamics of f...How to accurately simulate the distribution of forest species based upon their biological attributes has been a traditional biogeographical issue.Forest gap models are very useful tools for examining the dynamics of forest succession and revealing the species structure of vegetation.In the present study,the GFSM(Gongga Forest Succession Model) was developed and applied to simulate the distribution,composition and succession process of forests in 100 m elevation intervals.The results indicate that the simulated results of the tree species,quantities of the different types of trees,tree age and differences in DBH(diameter at breast height) composition were in line with the actual situation from 1400 to 3700 MASL(meters above sea level) on the eastern slope of Mt.Gongga.Moreover,the dominant species in the simulated results were the same as those in the surveyed database.Thus,the GFSM model can best simulate the features of forest dynamics and structure in the natural conditions of Mt.Gongga.The work provides a new approach to studying the structure and distribution characteristics of mountain ecosystems in varied elevations.Moreover,the results of this study suggest that the biogeochemistry mechanism model should be combined with the forestsuccession model to facilitate the ecological model in simulating the physical and chemical processes involved.展开更多
The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape....The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape. In the design of target plant community and configuration plants,it is required to select as far as possible plants that can blossom and bear fruit or pods. Then seeds of these plants can be harvested,processed and sold,and applied for other projects,so as to develop into a complete forest and grass seed industry chain. This not only reasonably utilizes land resources,but also provides a new approach to the problem of insufficient fine forest seed sources in China. This paper discussed the use of land resources in road side slope and forest and grass seed selection and breeding technology,and elaborated the industrialized development paths for forest and grass seed industries in road side slope. Finally,it arrived at following recommendations.( i) The construction of forest and grass industry economic belt using land resources in road side slope can realize maximum land value. Building a road can help people there get rich,and the type of land and water cultivates its type of forest and grass.( ii) It can make up for the losses incurred from construction of expressway and high-speed rail or destroying forest land,and it can increase farmers' income.( iii) It can increase the supply of domestic seeds,reduce seed import,save foreign exchange,and partly solve the problem of insufficient supply of forest and grass seeds.( iv) It is able to form a complete forest and grass seed industry economic cycle chain,increase employment,and provide new approaches for enriching and benefiting farmers.展开更多
The mutual-belt selective cutting was conducted in the secondary poplar-birch forests. The changes of environmental factors after cutting were observed. The environmental factors of effect belts(cutting belts) of 15m ...The mutual-belt selective cutting was conducted in the secondary poplar-birch forests. The changes of environmental factors after cutting were observed. The environmental factors of effect belts(cutting belts) of 15m in width had great changes. 10-m effect belts had unnoticed changes in environmental factors. The reserved belts with 10-m effect belts had a greater increase in DBH growth rate and volume growth rate. The reserved belts for 6-m and 8-m effect belts had lower increase in DBH and volume. The environmental factors of 6-m and 8-m effect belts did not change much. comparing with their reserved belts. Cluster analysis and principal component analysis for environmental factors between each two belts were also made. and the results proved that 10-m cutting belt is the best way for management of the secondary poplar-birch forests.展开更多
Global climate change is having long-term impacts on the geographic distribution of forest species. However, the response of vertical belts of mountain forests to climate change is still little known. The vertical dis...Global climate change is having long-term impacts on the geographic distribution of forest species. However, the response of vertical belts of mountain forests to climate change is still little known. The vertical distribution of forest vegetation(vertical vegetation belt) on Gongga Mountain in Southwest China has been monitored for 30 years. The forest alternation of the vertical vegetation belt under different climate conditions was simulated by using a mathematical model GFSM(the Gongga Forest Succession Model). Three possible Intergovernmental Panel on Climate Change(IPCC) climate scenarios(increase of air temperature and precipitation by 1.8℃/5%, 2.8℃/10% and 3.4℃/15% for B_1, A_1B and A_2 scenarios, respectively) were chosen to reflect lower, medium and higher changes of global climate. The vertical belts of mountainous vegetation will shift upward by approximately 300 m, 500 m and 600 m in the B_1, A_1B and A_2 scenarios, respectively, according to the simulated results. Thus, the alpine tree-line will move to a higher altitude. The simulation also demonstrated that, in a changing climate, the shift in the vegetation community will be a slow and extended process characterized by two main phases. During the initial phase, trees of the forest community degrade or die, owing to an inability to adapt to a warmer climate. This results in modest environment for the introduction of opportunistic species, consequently, the vegetation with new dominant tree species becomes predominant in the space vacated by the dead trees at the expense of previously dominated original trees as the succession succeed and climate change advance. Hence, the global climate change would dramatically change forest communities and tree species in mountainous regions because that the new forest community can grow only through the death of the original tree. Results indicated that climate change will cause the change of distribution and composition of forest communities on Gongga Mountain, and this change may enhance as the intensity of climate change increases. As a result, the alternation of death and rebirth would finally result in intensive landscape changes, and may strongly affect the eco-environment of mountainous regions.展开更多
During last decades, new trends appeared in the ecotones of the upper boundary of forests at the ridges surroundingLakeBaikal(Khamar-Daban and Baikal’sky Ridge): ones to advance of wood species (Pinus sibirica Du Tou...During last decades, new trends appeared in the ecotones of the upper boundary of forests at the ridges surroundingLakeBaikal(Khamar-Daban and Baikal’sky Ridge): ones to advance of wood species (Pinus sibirica Du Tour, Abies sibirica Ledeb., Larix sibirica Ledeb., Larix dahurica Lawson) out of timber stands into the area of subgoltsy with Pinus pumila (Pallas) Regel. up to mountain tundras. In average, this is from 100 to 200 - 300 meters (maximum up to500 m) in linear distance from the margin of dense timber stand. A burst of forests renewal occurred in 1989-1995, it resulted probably from a high productivity of the seeds of wood species due to warmer winters in 1980ies-1990ies which favoured the formation of favourable climate-edaphic conditions for the development of forest communities above the forests boundary on the ridges surrounding Lake Baikal.展开更多
Background:The role of wild foods in combating problems of food shortage is paramount.However,existing approaches to combat food insecurity shock have generally focused on reducing vulnerability via increasing product...Background:The role of wild foods in combating problems of food shortage is paramount.However,existing approaches to combat food insecurity shock have generally focused on reducing vulnerability via increasing productivity of domesticated foods.In contrast,approaches that enhance resilience mainly through wild food sources have been less focused.This study examined the contribution of wild foods to household resilience to food insecurity in the green famine belt of Ethiopia.Methods:A cross-sectional survey of 220 households was conducted using a structured questionnaire,key informant interviews,and semi-participant observations.Factor analysis was run using SPSS to analyze data.Correlation analysis was used to examine the direction and strength of association between wild foods and the income and food access(IFA),a latent proxy indicator of resilience.Cross-tabulation was also run to determine the proportion of households in each ethno-culture group under each resilience category.Results:The mean amount of wild foods obtained by households was 156.61 kg per household per annum.This was about 5%and 9%of,gross and,net food available from all sources respectively.Wild foods contributed well to household resilience as the factor loading(Factor2=0.467) was large enough and were significantly correlated with IFA(r=0.174).Wild vegetables were the most collected and consumed type of wild foods constituting 52.4%of total amount of wild foods.The total amount of wild foods was smaller than that of domesticated sources of food.The majority of households(38.6%) reported "reduced source of wild foods" as a reason for this.Smaller proportion of the indigenous(11.2%) than the non-indigenous(34.1%) ethno-culture group reported one or more reasons for their lower level of dependence on wild foods.Conclusion:From the study we concluded that wild foods had important contribution to households' resilience to food shortages and are likely to continue to contribute in the future,this being more to indigenous than non-indigenous ethno-culture group.Therefore,a resilience building policy that incorporates wild foods should be adopted,and research that aims at exploring their current status and future prospect are urgently required.展开更多
基金funded by the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX2-XB3-08)the National Natural Science Foundation of China (31070405)
文摘How to accurately simulate the distribution of forest species based upon their biological attributes has been a traditional biogeographical issue.Forest gap models are very useful tools for examining the dynamics of forest succession and revealing the species structure of vegetation.In the present study,the GFSM(Gongga Forest Succession Model) was developed and applied to simulate the distribution,composition and succession process of forests in 100 m elevation intervals.The results indicate that the simulated results of the tree species,quantities of the different types of trees,tree age and differences in DBH(diameter at breast height) composition were in line with the actual situation from 1400 to 3700 MASL(meters above sea level) on the eastern slope of Mt.Gongga.Moreover,the dominant species in the simulated results were the same as those in the surveyed database.Thus,the GFSM model can best simulate the features of forest dynamics and structure in the natural conditions of Mt.Gongga.The work provides a new approach to studying the structure and distribution characteristics of mountain ecosystems in varied elevations.Moreover,the results of this study suggest that the biogeochemistry mechanism model should be combined with the forestsuccession model to facilitate the ecological model in simulating the physical and chemical processes involved.
基金Supported by National Spark Plan Project(2010GA781004)Science and Technology Planning Project of Shenzhen(GCZX2015051514435234,CXZZ20150527171538718,and CXZZ20140422142833835)
文摘The construction of expressway and high-speed rail is at the sacrifice of the soil ecological environment. It brings about much damaged land and bare slope. It is necessary to restore vegetation and rebuild landscape. In the design of target plant community and configuration plants,it is required to select as far as possible plants that can blossom and bear fruit or pods. Then seeds of these plants can be harvested,processed and sold,and applied for other projects,so as to develop into a complete forest and grass seed industry chain. This not only reasonably utilizes land resources,but also provides a new approach to the problem of insufficient fine forest seed sources in China. This paper discussed the use of land resources in road side slope and forest and grass seed selection and breeding technology,and elaborated the industrialized development paths for forest and grass seed industries in road side slope. Finally,it arrived at following recommendations.( i) The construction of forest and grass industry economic belt using land resources in road side slope can realize maximum land value. Building a road can help people there get rich,and the type of land and water cultivates its type of forest and grass.( ii) It can make up for the losses incurred from construction of expressway and high-speed rail or destroying forest land,and it can increase farmers' income.( iii) It can increase the supply of domestic seeds,reduce seed import,save foreign exchange,and partly solve the problem of insufficient supply of forest and grass seeds.( iv) It is able to form a complete forest and grass seed industry economic cycle chain,increase employment,and provide new approaches for enriching and benefiting farmers.
文摘The mutual-belt selective cutting was conducted in the secondary poplar-birch forests. The changes of environmental factors after cutting were observed. The environmental factors of effect belts(cutting belts) of 15m in width had great changes. 10-m effect belts had unnoticed changes in environmental factors. The reserved belts with 10-m effect belts had a greater increase in DBH growth rate and volume growth rate. The reserved belts for 6-m and 8-m effect belts had lower increase in DBH and volume. The environmental factors of 6-m and 8-m effect belts did not change much. comparing with their reserved belts. Cluster analysis and principal component analysis for environmental factors between each two belts were also made. and the results proved that 10-m cutting belt is the best way for management of the secondary poplar-birch forests.
基金funded by the National Natural Science Foundation of China (Grant Nos. 41671016 and 41671262)
文摘Global climate change is having long-term impacts on the geographic distribution of forest species. However, the response of vertical belts of mountain forests to climate change is still little known. The vertical distribution of forest vegetation(vertical vegetation belt) on Gongga Mountain in Southwest China has been monitored for 30 years. The forest alternation of the vertical vegetation belt under different climate conditions was simulated by using a mathematical model GFSM(the Gongga Forest Succession Model). Three possible Intergovernmental Panel on Climate Change(IPCC) climate scenarios(increase of air temperature and precipitation by 1.8℃/5%, 2.8℃/10% and 3.4℃/15% for B_1, A_1B and A_2 scenarios, respectively) were chosen to reflect lower, medium and higher changes of global climate. The vertical belts of mountainous vegetation will shift upward by approximately 300 m, 500 m and 600 m in the B_1, A_1B and A_2 scenarios, respectively, according to the simulated results. Thus, the alpine tree-line will move to a higher altitude. The simulation also demonstrated that, in a changing climate, the shift in the vegetation community will be a slow and extended process characterized by two main phases. During the initial phase, trees of the forest community degrade or die, owing to an inability to adapt to a warmer climate. This results in modest environment for the introduction of opportunistic species, consequently, the vegetation with new dominant tree species becomes predominant in the space vacated by the dead trees at the expense of previously dominated original trees as the succession succeed and climate change advance. Hence, the global climate change would dramatically change forest communities and tree species in mountainous regions because that the new forest community can grow only through the death of the original tree. Results indicated that climate change will cause the change of distribution and composition of forest communities on Gongga Mountain, and this change may enhance as the intensity of climate change increases. As a result, the alternation of death and rebirth would finally result in intensive landscape changes, and may strongly affect the eco-environment of mountainous regions.
文摘During last decades, new trends appeared in the ecotones of the upper boundary of forests at the ridges surroundingLakeBaikal(Khamar-Daban and Baikal’sky Ridge): ones to advance of wood species (Pinus sibirica Du Tour, Abies sibirica Ledeb., Larix sibirica Ledeb., Larix dahurica Lawson) out of timber stands into the area of subgoltsy with Pinus pumila (Pallas) Regel. up to mountain tundras. In average, this is from 100 to 200 - 300 meters (maximum up to500 m) in linear distance from the margin of dense timber stand. A burst of forests renewal occurred in 1989-1995, it resulted probably from a high productivity of the seeds of wood species due to warmer winters in 1980ies-1990ies which favoured the formation of favourable climate-edaphic conditions for the development of forest communities above the forests boundary on the ridges surrounding Lake Baikal.
文摘Background:The role of wild foods in combating problems of food shortage is paramount.However,existing approaches to combat food insecurity shock have generally focused on reducing vulnerability via increasing productivity of domesticated foods.In contrast,approaches that enhance resilience mainly through wild food sources have been less focused.This study examined the contribution of wild foods to household resilience to food insecurity in the green famine belt of Ethiopia.Methods:A cross-sectional survey of 220 households was conducted using a structured questionnaire,key informant interviews,and semi-participant observations.Factor analysis was run using SPSS to analyze data.Correlation analysis was used to examine the direction and strength of association between wild foods and the income and food access(IFA),a latent proxy indicator of resilience.Cross-tabulation was also run to determine the proportion of households in each ethno-culture group under each resilience category.Results:The mean amount of wild foods obtained by households was 156.61 kg per household per annum.This was about 5%and 9%of,gross and,net food available from all sources respectively.Wild foods contributed well to household resilience as the factor loading(Factor2=0.467) was large enough and were significantly correlated with IFA(r=0.174).Wild vegetables were the most collected and consumed type of wild foods constituting 52.4%of total amount of wild foods.The total amount of wild foods was smaller than that of domesticated sources of food.The majority of households(38.6%) reported "reduced source of wild foods" as a reason for this.Smaller proportion of the indigenous(11.2%) than the non-indigenous(34.1%) ethno-culture group reported one or more reasons for their lower level of dependence on wild foods.Conclusion:From the study we concluded that wild foods had important contribution to households' resilience to food shortages and are likely to continue to contribute in the future,this being more to indigenous than non-indigenous ethno-culture group.Therefore,a resilience building policy that incorporates wild foods should be adopted,and research that aims at exploring their current status and future prospect are urgently required.
