The Bashu area was one of the most civilized agricultural areas in ancient China.Since the late Eastern Han Dynasty,it has been reputed as the“Land of Abundance”due to its abundant resources.Archaeological data show...The Bashu area was one of the most civilized agricultural areas in ancient China.Since the late Eastern Han Dynasty,it has been reputed as the“Land of Abundance”due to its abundant resources.Archaeological data show that the Shu area cultivated millet as early as the prehistoric period.The legend goes that Can Cong was the first ruler of the Shu area during the pre-Qin period,indicating that agricultural production at that time had made great progress compared with the prehistoric period.During this period,the agricultural pattern of the Shu area experienced profound changes,from dryland millet farming originating from the Western Sichuan Plateau to rice farming that is more suitable for Sichuan Basin,especially for the Chengdu Plain,where there are abundant rainfalls and high temperatures.Since then,rice farming has become a long-established farming tradition in the Shu area.The agricultural production tools and grain crop seeds unearthed from the Baodun site,where the archaeological remains of Can Cong Culture were discovered,show the prosperity of early agriculture in the Shu area.During the Baodun Culture period,the accelerated economic and social development in the Shu area promoted complicated and hierarchical changes in the social organization structure of settlements,which gradually evolved into early states.展开更多
This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorph...This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.展开更多
Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their pot...Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their potential ecological risks in the topsoil( 0-20 cm) of cultivated land in Donghai County,a typical agricultural area along the Southeast Coast of China.The results showed that the average content of heavy metals in the cultivated soil of Donghai County was not over the risk screening values set in the Environmental Quality Standard for Soils.However,it was worth noting that in some of the sampling points,the content of Cr exceeded the risk screening value,and the standard exceeding points accounted for 24.74% of the total.In addition,the average content of Cr,Ni,As,Cd,Pb and Hg exceeded the soil background values of Jiangsu Province,and values for Cd,Cr and Pb were more than 1.5 times of the soil background value of Jiangsu Province.The heavy metals were at the medium integrated potential ecological risk level,and the potential ecological risk indices were high in the east and low in the west,and distributed in interlaced island shape.The potential ecological risk indices of the plains in the east were higher than those of the central gentle slope area and the western hillock area.The potential ecological risk was at a high level in Niushan Town which was situated the county center and in some regions with high urbanization levels.展开更多
Stand structure, diversity and regeneration status of woody species were investigated in open and exclosed dry woodland sites in Island Safari, Shorobe and Xobe, northeastern Botswana. A total of 105, 111 and 130 quad...Stand structure, diversity and regeneration status of woody species were investigated in open and exclosed dry woodland sites in Island Safari, Shorobe and Xobe, northeastern Botswana. A total of 105, 111 and 130 quadrats, measuring 20 × 20 m each, were laid down along parallel line transects in the three sites, respectively, to collect data. A total of 47 species, representing 16 families and 24 genera, were recorded in the study sites. Of these, 33 species representing 13 families and 20 genera, 41 species representing 15 families and 23 genera and 27 species representing 10 families and 14 genera were encountered in Island Safari, Shorobe and Xobe, respectively. The most diverse family was Fabaceae followed by Combretaceae and Tiliaceae at all the three sites. The most diverse genus was Acacia, followed by Combretum and Grewia. The diversity of woody species in the study sites were 2.18, 2.15 and 1.5 in Shorobe, Island Safari and Xobe, respectively, while their corresponding evenness values were 0.6, 0.6 and 0.5, respectively. The mean densities of the woody species encountered in Island Safari, Shorobe and Xobe were 2629, 4271 and 2745 individuals haǃ, respectively. The five densest species were Colophospermum mopane, Dichrostachys cinerea, Acacia tortilis, Philenoptera violacea and Terminalia prunioides in Island Safari, C. mopane, A. tortilis, A. erioloba, P. violacea and D. cinerea in Shorobe and Acacia mellifera, A. tortilis, P. nelsii, A. luederitzii and A. erubescens in Xobe. The highest important value index values were exhibited by C. mopane, D. cinerea, A. tortilis, P. violacea and T. prunioides in Island Safari, C. mopane, A. erioloba, A. tortilis, P. violacea and C. imberbe in Shorobe, and A. mellifera, A. tortilis, P. nelsii and A. luederitzii in Xobe. The alarming result was the fact that 71%, 80% and 85% of the woody species recorded in Island Safari, Shorobe and Xobe, respectively, exhibited hampered regeneration and, thus, unhealthy population structures. Therefore, there is an urgent need to address the observed unhealthy population structures of the woody species through investigation of the major causes of their hampered regeneration, and also designing measures that will facilitate natural and artificial regeneration of these species at the three study sites.展开更多
This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net inc...This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net income of households. That means the increase of net income of farm households is chiefly from off-farm industries,more than from agriculture. The authors therefore conclude that the "poverty" in mountain areas or the gap between mountain areas and plain areas lies in the underdevelopment of off-farm industries in mountain areas. Finally,the authors make suggestions of strategic adjustment of economic structure: 1) present situation of mountain areas in China should be fully considered; 2) a full industrial system is not our desire; 3) advantageous industries should be promoted to create famous products; 4) industrialization and urbanization in mountain areas should be promoted and so on.展开更多
[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basi...[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basic weather stations as well as wind data during 2005 -2007 de- termined by six gradient wind measurement towers in northern costal areas of Jiangsu Province, the spatial and temporal distribution of tropical cy- clones influencing northern coastal areas of Jiangsu Province were discussed firstly, and then the possible effects of tropical cyclones on wind farms in the northern costal areas were assessed, finally some suggestions about type selection and parameter design of wind turbines were proposed. Restult Annual average number of tropical cyclones influencing northern coastal areas of Jiangsu Province was 1.7, and the first two kinds of tropical cyclones were dominant in quantity, accounting for about 73% for total quantity. The quantity of tropical cyclones bringing substantial economic benefits to wind farms accounted for 87.7% of total quantity, with annual average quantity of 1.5. Maximum wind speed appearing every 50 years did not exceed 37.5 m/s, in accord with the national Grade-Ill standard for safe operation of wind turbines. 2.1% -3.8% of turbulence intensity ei- genvalues at a height of 70 m exceeded the maximum anti-turbulence intensity designed by IEC (0.16), and it is suggested that anti-turbulence in- tensity parameter of wind turbines in northem costal areas of East China should be changed to 0.31 -0.41. [ Conclusion] The research could provide scientific references for design and choice of wind turbines as well as operation and management of wind farms in the study region in future.展开更多
Adhering to the " red line" of 1800 million mu of arable land is China's arable land protection guideline and policy,and the " red line" places emphasis on both quantity and quality of arable l...Adhering to the " red line" of 1800 million mu of arable land is China's arable land protection guideline and policy,and the " red line" places emphasis on both quantity and quality of arable land. Taking Shanxi's Anze County as an example,based on ecological safety and natural suitability criteria,we select 10 evaluation indicators to evaluate the farming suitability of existing land in the county. Results show that Anze County needs to reuse 48. 7% of the existing arable land for ecological purpose in order to ensure ecological safety. It still retains 51. 3%of existing arable land after abandoning tillage,which can ensure 0. 15 ha of arable land per capita,743. 12 kg of grain per capita and 170%of food self-sufficiency rate,thereby fully ensuring food safety. The farming suitability evaluation of land resources should not only consider the natural suitability of land,but also consider ecological safety. Faced with the new situation of arable land protection,it is necessary to explore new farmland protection theories and indicator systems based on actual conditions,to meet the requirements of sustainable development of population,resources and ecology.展开更多
Coffea cultivation with shade tree is used for improving soil health,increasing coffea production,sustaining agro ecology.The study was attended in two kebele,on 36 farmers’fields,at Gololcha district of East Arsi zo...Coffea cultivation with shade tree is used for improving soil health,increasing coffea production,sustaining agro ecology.The study was attended in two kebele,on 36 farmers’fields,at Gololcha district of East Arsi zone.The study was intended to assess the influence of coffea shade trees on farm lands versus mountainous area.Household interviews were used to get imperative separately,i.e.from old farmers,middle age farmers and young farmers.Significant difference value was observed between farm land and mountainous area coverage.Based on this respondents’idea,before 25-30 years;the‘condition of tree coverage at mountainous’area in Arsi Gololcha district was‘medium condition’but not normal that means as deforestation of mountainous area have been starting before 30 years’time;while the condition of tree coverage at farmland area also has been starting before 30 years’time.The third respondents’idea was interpreted with the real situation of the district,that it gave us a constructive inspiration on the role of coffea shade tree to enable the farm land to be taken as regular natural forest.The existing coffea shade trees are Cordia africana followed by Erythrina abyssinica and Acacia senegal.Farmers accounted 95%of coffea shade users and 4.6%without shade users.The respondents said that even if the rainfall intensity is increasing at farmland rather than mountainous area occasionally due to shade tree effect.On the contrary side,mountainous area exposed to deforestation since the farmers have been shifting to hilly side for their livelihood dependency.展开更多
The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and sui...The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and suitable solutions to the problems of fish farming.Different participatory rapid appraisal tools such as focus group discussion,field visits,and farmers’interviews were used to collect relevant fish farming information in the study area.The polyculture method was the most practised aquaculture method.Among the selected farms,eleven fish species were identified as culture species.The transportation cost for seeds purchased from remote areas was high(11%of total seed cost).The average transportation-related mortality of fish fry and fingerlings was 7.2%and 2.8%.Feed cost was found as the major cost(58.4%)in aquaculture.Costs and revenue for fish production per decimal varied from BDT 311 to 3528 and BDT 23 to 1268.Utilization of vacant lake,youth and women engagement,integrated aquaculture,the desire of people to engage in aquaculture,and available human resources were found as significant prospects.The major problems identified were lack of hatchery,high feed cost,lack of stakeholder linkage,lack of capital for fish farming,and lack of proper knowledge,guidelines,and consultancy for fish culture.A community-based aquaculture model was proposed to overcome the present challenges and problems in the study area.The model may help to expand aquaculture and thus improve the livelihood and socio-economic status of the people of the hilly areas of Bangladesh.展开更多
基金This paper is a joint achievement of the Humanities and Social Science Research Project of the Chongqing Municipal Education Commission entitled“Exploration and Inheritance of the Core Values of Ba Culture from the Perspective of Cultural Confidence”(Project No.:20SKGH034)the 2019 University-level Philosophy and Social Sciences Special Research Project of Chongqing Medical University entitled“Research on the Chineseization of Indigenous Ethnic Groups in Bashu Area in the Qin and Han Dynasties”(Project No.:ZX190306).
文摘The Bashu area was one of the most civilized agricultural areas in ancient China.Since the late Eastern Han Dynasty,it has been reputed as the“Land of Abundance”due to its abundant resources.Archaeological data show that the Shu area cultivated millet as early as the prehistoric period.The legend goes that Can Cong was the first ruler of the Shu area during the pre-Qin period,indicating that agricultural production at that time had made great progress compared with the prehistoric period.During this period,the agricultural pattern of the Shu area experienced profound changes,from dryland millet farming originating from the Western Sichuan Plateau to rice farming that is more suitable for Sichuan Basin,especially for the Chengdu Plain,where there are abundant rainfalls and high temperatures.Since then,rice farming has become a long-established farming tradition in the Shu area.The agricultural production tools and grain crop seeds unearthed from the Baodun site,where the archaeological remains of Can Cong Culture were discovered,show the prosperity of early agriculture in the Shu area.During the Baodun Culture period,the accelerated economic and social development in the Shu area promoted complicated and hierarchical changes in the social organization structure of settlements,which gradually evolved into early states.
基金Sub-global project of UN Millennium Ecosystem Assessment (MA) Programkey project of international collaboration funded by the Ministry of Science and TechnologyThe Knowledge Innovation Project of CAS, No.KZCX02-308
文摘This paper discusses land-use changes in the interlock area of farming and pasturing (IAFP) in northern China. It presents detailed analyses of land-use features in the IAFP, which are controlled by the macro geomorphic units and geophysical conditions-constraints or advantages. Additionally, it selects some indicators, according to the availability in acquiring and processing their quantitative data, to analyze the canonical correlations between the typical conversion of grassland and geophysical conditions. The preliminary study indicates that the physical conditions are of great advantages to the development of grassland. There exists significant correlation between land use change and some geophysical conditions.
文摘Classical statistics,Inverse Distance Weighted and Hakasnson potential ecological index were used to study the distribution characteristics of 8 kinds of heavy metals( Cr,Ni,Cu,Zn,As,Cd,Pb and Hg) as well as their potential ecological risks in the topsoil( 0-20 cm) of cultivated land in Donghai County,a typical agricultural area along the Southeast Coast of China.The results showed that the average content of heavy metals in the cultivated soil of Donghai County was not over the risk screening values set in the Environmental Quality Standard for Soils.However,it was worth noting that in some of the sampling points,the content of Cr exceeded the risk screening value,and the standard exceeding points accounted for 24.74% of the total.In addition,the average content of Cr,Ni,As,Cd,Pb and Hg exceeded the soil background values of Jiangsu Province,and values for Cd,Cr and Pb were more than 1.5 times of the soil background value of Jiangsu Province.The heavy metals were at the medium integrated potential ecological risk level,and the potential ecological risk indices were high in the east and low in the west,and distributed in interlaced island shape.The potential ecological risk indices of the plains in the east were higher than those of the central gentle slope area and the western hillock area.The potential ecological risk was at a high level in Niushan Town which was situated the county center and in some regions with high urbanization levels.
文摘Stand structure, diversity and regeneration status of woody species were investigated in open and exclosed dry woodland sites in Island Safari, Shorobe and Xobe, northeastern Botswana. A total of 105, 111 and 130 quadrats, measuring 20 × 20 m each, were laid down along parallel line transects in the three sites, respectively, to collect data. A total of 47 species, representing 16 families and 24 genera, were recorded in the study sites. Of these, 33 species representing 13 families and 20 genera, 41 species representing 15 families and 23 genera and 27 species representing 10 families and 14 genera were encountered in Island Safari, Shorobe and Xobe, respectively. The most diverse family was Fabaceae followed by Combretaceae and Tiliaceae at all the three sites. The most diverse genus was Acacia, followed by Combretum and Grewia. The diversity of woody species in the study sites were 2.18, 2.15 and 1.5 in Shorobe, Island Safari and Xobe, respectively, while their corresponding evenness values were 0.6, 0.6 and 0.5, respectively. The mean densities of the woody species encountered in Island Safari, Shorobe and Xobe were 2629, 4271 and 2745 individuals haǃ, respectively. The five densest species were Colophospermum mopane, Dichrostachys cinerea, Acacia tortilis, Philenoptera violacea and Terminalia prunioides in Island Safari, C. mopane, A. tortilis, A. erioloba, P. violacea and D. cinerea in Shorobe and Acacia mellifera, A. tortilis, P. nelsii, A. luederitzii and A. erubescens in Xobe. The highest important value index values were exhibited by C. mopane, D. cinerea, A. tortilis, P. violacea and T. prunioides in Island Safari, C. mopane, A. erioloba, A. tortilis, P. violacea and C. imberbe in Shorobe, and A. mellifera, A. tortilis, P. nelsii and A. luederitzii in Xobe. The alarming result was the fact that 71%, 80% and 85% of the woody species recorded in Island Safari, Shorobe and Xobe, respectively, exhibited hampered regeneration and, thus, unhealthy population structures. Therefore, there is an urgent need to address the observed unhealthy population structures of the woody species through investigation of the major causes of their hampered regeneration, and also designing measures that will facilitate natural and artificial regeneration of these species at the three study sites.
文摘This paper reveals that agricultural growth trend in China is strongly correlated with the growth of off-farm industries-the curve of net income from off-farm industries reflects the general characteristics of net income of households. That means the increase of net income of farm households is chiefly from off-farm industries,more than from agriculture. The authors therefore conclude that the "poverty" in mountain areas or the gap between mountain areas and plain areas lies in the underdevelopment of off-farm industries in mountain areas. Finally,the authors make suggestions of strategic adjustment of economic structure: 1) present situation of mountain areas in China should be fully considered; 2) a full industrial system is not our desire; 3) advantageous industries should be promoted to create famous products; 4) industrialization and urbanization in mountain areas should be promoted and so on.
基金Supported by the Science and Technology Planning Project of Lianyungang City,China(SH0916,SH1207)
文摘[Objectivel The study aimed to assess the risk of tropical cyclones to wind farm operation in northem costal areas of Jiangsu Province. [Metbod] Based on tropical cyclone data during 1951 -2011 from nine national basic weather stations as well as wind data during 2005 -2007 de- termined by six gradient wind measurement towers in northern costal areas of Jiangsu Province, the spatial and temporal distribution of tropical cy- clones influencing northern coastal areas of Jiangsu Province were discussed firstly, and then the possible effects of tropical cyclones on wind farms in the northern costal areas were assessed, finally some suggestions about type selection and parameter design of wind turbines were proposed. Restult Annual average number of tropical cyclones influencing northern coastal areas of Jiangsu Province was 1.7, and the first two kinds of tropical cyclones were dominant in quantity, accounting for about 73% for total quantity. The quantity of tropical cyclones bringing substantial economic benefits to wind farms accounted for 87.7% of total quantity, with annual average quantity of 1.5. Maximum wind speed appearing every 50 years did not exceed 37.5 m/s, in accord with the national Grade-Ill standard for safe operation of wind turbines. 2.1% -3.8% of turbulence intensity ei- genvalues at a height of 70 m exceeded the maximum anti-turbulence intensity designed by IEC (0.16), and it is suggested that anti-turbulence in- tensity parameter of wind turbines in northem costal areas of East China should be changed to 0.31 -0.41. [ Conclusion] The research could provide scientific references for design and choice of wind turbines as well as operation and management of wind farms in the study region in future.
文摘Adhering to the " red line" of 1800 million mu of arable land is China's arable land protection guideline and policy,and the " red line" places emphasis on both quantity and quality of arable land. Taking Shanxi's Anze County as an example,based on ecological safety and natural suitability criteria,we select 10 evaluation indicators to evaluate the farming suitability of existing land in the county. Results show that Anze County needs to reuse 48. 7% of the existing arable land for ecological purpose in order to ensure ecological safety. It still retains 51. 3%of existing arable land after abandoning tillage,which can ensure 0. 15 ha of arable land per capita,743. 12 kg of grain per capita and 170%of food self-sufficiency rate,thereby fully ensuring food safety. The farming suitability evaluation of land resources should not only consider the natural suitability of land,but also consider ecological safety. Faced with the new situation of arable land protection,it is necessary to explore new farmland protection theories and indicator systems based on actual conditions,to meet the requirements of sustainable development of population,resources and ecology.
文摘Coffea cultivation with shade tree is used for improving soil health,increasing coffea production,sustaining agro ecology.The study was attended in two kebele,on 36 farmers’fields,at Gololcha district of East Arsi zone.The study was intended to assess the influence of coffea shade trees on farm lands versus mountainous area.Household interviews were used to get imperative separately,i.e.from old farmers,middle age farmers and young farmers.Significant difference value was observed between farm land and mountainous area coverage.Based on this respondents’idea,before 25-30 years;the‘condition of tree coverage at mountainous’area in Arsi Gololcha district was‘medium condition’but not normal that means as deforestation of mountainous area have been starting before 30 years’time;while the condition of tree coverage at farmland area also has been starting before 30 years’time.The third respondents’idea was interpreted with the real situation of the district,that it gave us a constructive inspiration on the role of coffea shade tree to enable the farm land to be taken as regular natural forest.The existing coffea shade trees are Cordia africana followed by Erythrina abyssinica and Acacia senegal.Farmers accounted 95%of coffea shade users and 4.6%without shade users.The respondents said that even if the rainfall intensity is increasing at farmland rather than mountainous area occasionally due to shade tree effect.On the contrary side,mountainous area exposed to deforestation since the farmers have been shifting to hilly side for their livelihood dependency.
文摘The study was carried out in Matiranga Upazila,Bandarban district,which is considered one of Bangladesh’s major hill tract regions.The study aimed to identify present farming conditions,prospects,and problems and suitable solutions to the problems of fish farming.Different participatory rapid appraisal tools such as focus group discussion,field visits,and farmers’interviews were used to collect relevant fish farming information in the study area.The polyculture method was the most practised aquaculture method.Among the selected farms,eleven fish species were identified as culture species.The transportation cost for seeds purchased from remote areas was high(11%of total seed cost).The average transportation-related mortality of fish fry and fingerlings was 7.2%and 2.8%.Feed cost was found as the major cost(58.4%)in aquaculture.Costs and revenue for fish production per decimal varied from BDT 311 to 3528 and BDT 23 to 1268.Utilization of vacant lake,youth and women engagement,integrated aquaculture,the desire of people to engage in aquaculture,and available human resources were found as significant prospects.The major problems identified were lack of hatchery,high feed cost,lack of stakeholder linkage,lack of capital for fish farming,and lack of proper knowledge,guidelines,and consultancy for fish culture.A community-based aquaculture model was proposed to overcome the present challenges and problems in the study area.The model may help to expand aquaculture and thus improve the livelihood and socio-economic status of the people of the hilly areas of Bangladesh.