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Exploring the Forest Cover Changes and Influential Factors of Dongsithouane National Production Forest Area, Savannakhet Province, Lao PDR
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作者 Souvanthone Douangphachachanh Chittana Phompila +5 位作者 Dipjoy Chakma Inta Chanthavong Maliphone Douangphachanh Puvadol Doydee Pengxiang Zhao Yuanchun Yu 《Journal of Data Analysis and Information Processing》 2024年第3期432-461,共30页
The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant chang... The Dongsithouane National Production Forest (DNPF) is one of the largest natural forest areas in Savannakhet, Lao PDR, which has been a vital support for the local community’s livelihood, Recently, significant changes in land use and land cover (LULC) have been observed in this area, leading to a reduction of natural forests. There were two separate methods of this study: firstly, to identify LULC changes across three different periods, spectral imagery from the Landsat 5 Thematic Mapper (TM) for the years 2001 and 2011, and the Landsat 8 Operational Land Imager (OLI) for 2021 were used as the primary data sources. The satellite images were preprocessed for various forest classes, including pretreatment of the top of atmosphere reflectance by using QGIS software’s semi-automatic classification plug-in (SCP), and ArcGIS was used for post-classification. A supervised classification approach was applied to the satellite images from 2001, 2011, and 2021 to generate diverse maps of LULC. Secondly, a household survey dataset was used to investigate influential factors. Approximately 220 households were interviewed in order to collect socio-economic information (including data on population growth, increased business activities, location of the area, agriculture land expansion, and need for settlement land). Household survey data was analyzed by using SPSS. Descriptive statistics, including frequency distributions and percentages, were applied to observe characteristics. Additionally, a binary logistic regression model was used to analyze the socioeconomic factors related to LULC change in DNPF. Key findings indicated a decline in natural forest areas within the study site. Specifically, both dry dipterocarp forest (−11.35%) and mixed deciduous forest (−0.18%) decreased from 2001 to 2021. The overall accuracy of the LULC maps was 94%, 86%, and 89% for the years 2001, 2011, and 2021 respectively. In contrast, agricultural land increased significantly by 155.70%, while built-up land, and water bodies increased by 65.54% and 35.33%, respectively. The results also highlighted a significant increase in construction land, up to 65.54%. Furthermore, the study found a correlation between agricultural expansion and a reduction of forest areas, along with an increase in built-up land along the forest areas’ boundaries. Timber exploitation and charcoal production also contributed to the decline in forest cover. The logistic regression model identified significant determinants of LULC change, including the area’s location, agricultural land expansion, increased business activity, and the need for settlement land. These factors have influenced the management of DNPF. Urgent sustainable management practices and actions, including forest ecosystem protection, village agricultural zoning, water source and watershed protection and public awareness, are required to preserve the forest areas of DNPF. 展开更多
关键词 Land Use/Land Cover Change QGIS SCP Socioeconomic Factor Dongsithouane National production forest Lao PDR
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The Influence of forest certification on forest product trade 被引量:2
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作者 郑仰南 蒋敏元 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第4期316-318,338,共3页
Forest certification is considered to be complementary to forest management policies and takes a significant effect on forest product trade. In recent decade, it has been followed with interest and approved by governm... Forest certification is considered to be complementary to forest management policies and takes a significant effect on forest product trade. In recent decade, it has been followed with interest and approved by governments and forestry de-partments in the world. This paper analyzes the influence of forest certification on forest product trade in the world, including the interest in certification in exporting countries and importing countries, trade flow and business competition, and the demands for Certified Forest Products (CFPs) and also discusses the influence of forest certification on forest product trade in China. 展开更多
关键词 forest Certification Certified forest products forest product Trade
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Does ash dieback affect the reproductive ecology of Fraxinus excelsior L.?
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作者 Anna‑Katharina Eisen Lisa Buchner +1 位作者 Barbara Fussi Susanne Jochner‑Oette 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期54-69,共16页
Forest tree species reproduction is a key factor in maintaining the genetic diversity of future generations and the stability of forest ecosystems.The ongoing ash dieback disease could affect the reproductive ecology ... Forest tree species reproduction is a key factor in maintaining the genetic diversity of future generations and the stability of forest ecosystems.The ongoing ash dieback disease could affect the reproductive ecology of Fraxinus excelsior L.and have a major impact on the quantity and quality of pollen and seeds.In this study,we investigated pollen production and viability of pollen and seeds of ash trees with different health status from 2018 to 2022.Inflorescences were collected from 105 trees(pollen production),pollen from 125 trees(pollen viability),and seeds from 53 trees(seed quality)in two seed orchards and in one floodplain forest in southern Germany.Not all parameters were examined at every site every year.The average pollen production per tree was estimated at 471.2±647.9 billion pollen grains.In addition,we found that a high number of inflorescences did not equate to high pollen production per inflorescence.Pollen production of healthy and diseased trees did not differ significantly,although only 47%of severely diseased male trees(vs.72%for healthy trees)produced flowers.With regards to pollen viability,the TTC test showed an average viability of 73%±17%.Overall,there was a slight tendency for diseased trees to have less viable pollen.However,a significant difference could only be calculated for trees in the floodplain forest.The percentage of germinable seeds in 2018 was 38%in the floodplain forest and 57%in one of the seed orchards.The percentage of viable seeds(TTC test)ranged from 17 to 22%in the orchards in 2020.Non-viable seeds were usually heavily infested by insects.In general,seed quality was not significantly different between healthy and diseased trees.Our results indicate that ash dieback affects flower formation and pollen viability but not pollen production or seed quality.Nevertheless,the fact that hardly any flowering was observed,especially for trees that were seriously affected,suggests a negative effect of ash dieback on reproductive performance.Thus,severely diseased trees will transfer their genes to a smaller extent to the next generation. 展开更多
关键词 Common ash Seed orchard Floodplain forest Pollen production VIaBILITY TTC test Seed stratification PHENOLOGY
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Assessing the role of forest resources in improving rural livelihoods in West Bengal of India
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作者 Soumen BISUI Pravat Kumar SHIT 《Regional Sustainability》 2024年第2期75-88,共14页
Forest resources play a vital role in supporting the livelihoods of rural communities residing in forest-rich areas.In India,a forest-rich country,a significant proportion of non-timber forest products(NTFPs)is consum... Forest resources play a vital role in supporting the livelihoods of rural communities residing in forest-rich areas.In India,a forest-rich country,a significant proportion of non-timber forest products(NTFPs)is consumed locally,supporting numerous rural communities relying on forests for essential resources,such as firewood,timber,and NTFPs.This study focuses on two forest-dominant districts in West Bengal of India,namely,Jhargram District and Paschim Medinipur District.Furthermore,this study aims to enhance the understanding of forest-dependent communities by comparing the standard of living among different village classes.Thus,we categorized villages into three classes based on the distance from home to forests,including inner villages,fringe villages,and outer villages.Through focus group discussions and household surveys,we explored the sources of local economy,income sources of household,and reasons for economic diversification in different village classes.The study findings confirm that substantial variations existed in the income sources and the standard of living in these villages.Forest income varied dramatically among the three village classes,with inner villages having greater forest income than fringe villages and outer villages.Meanwhile,households in outer villages depended on forests and engaged in diverse economic activities for their livelihoods.Compared with inner and fringe villages,households in outer villages derived a significant portion of their income from livestock.This discrepancy can be attributed to challenges,such as inadequate transportation,communication,and underdeveloped market chains in inner villages.Moreover,these findings emphasize the need to develop sustainable forest management practices,create alternative income-generation opportunities,and improve infrastructure and market access in inner villages,as well as promote economic diversification in outer villages.Through targeted policy measures,these forest-rich regions can achieve improved livelihoods,enhanced standard of living,and increased resilience for their communities. 展开更多
关键词 Non-timber forest products(NTFPs) forest resources Standard of living INDEX LIVELIHOOD dependency index Income sources INDIa
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Production Chain Length and PPI-CPI Divergence:Analysis Based on the Global Input-output Price Model
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作者 Ni Hongfu Yan Bingqian Wu Liyuan 《China Economist》 2024年第3期49-69,共21页
Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production ... Productivity and international energy price shocks are reflected in PPI and CPI via industrial chains.China’s in-depth participation into the global value chains has increasingly lengthened its industrial production chains.The question is how the changing length of production chains will affect CPI and PPI,as well as CPI-PPI correlation?By constructing a global input-output price model,this paper offers a theoretical discussion on the impact of production chain length on the CPI-PPI divergence.Our findings suggest that the price shock of international bulk commodities has a greater impact on China’s PPI than that on CPI.The effects on both China’s PPI and CPI estimated by using the single-country input-output model are higher than the results estimated with the global input-output model.However,the difference between CPI and PPI variations estimated with the global input-output model is greater than the result estimated with the single-country input-output model,which supports the view that the lengthening of production chains,especially international production chains,leads to a divergence between CPI and PPI.Empirical results based on cross-national panel data also suggest that the lengthening of production chains has reduced the CPI-PPI correlation for countries,i.e.the lengthening of production chains has increased the PPI-CPI divergence.That is to say,policymakers should target not just CPI in maintaining price stability,but instead focus on the stability of both PPI and CPI.Efforts can be made to proactively adjust the price index system,and formulate the industrial chain price index. 展开更多
关键词 Global value chains length of production chains consumer price index producer price index
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Data cleaning method for the process of acid production with flue gas based on improved random forest 被引量:3
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作者 Xiaoli Li Minghua Liu +2 位作者 Kang Wang Zhiqiang Liu Guihai Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第7期72-84,共13页
Acid production with flue gas is a complex nonlinear process with multiple variables and strong coupling.The operation data is an important basis for state monitoring,optimal control,and fault diagnosis.However,the op... Acid production with flue gas is a complex nonlinear process with multiple variables and strong coupling.The operation data is an important basis for state monitoring,optimal control,and fault diagnosis.However,the operating environment of acid production with flue gas is complex and there is much equipment.The data obtained by the detection equipment is seriously polluted and prone to abnormal phenomena such as data loss and outliers.Therefore,to solve the problem of abnormal data in the process of acid production with flue gas,a data cleaning method based on improved random forest is proposed.Firstly,an outlier data recognition model based on isolation forest is designed to identify and eliminate the outliers in the dataset.Secondly,an improved random forest regression model is established.Genetic algorithm is used to optimize the hyperparameters of the random forest regression model.Then the optimal parameter combination is found in the search space and the trend of data is predicted.Finally,the improved random forest data cleaning method is used to compensate for the missing data after eliminating abnormal data and the data cleaning is realized.Results show that the proposed method can accurately eliminate and compensate for the abnormal data in the process of acid production with flue gas.The method improves the accuracy of compensation for missing data.With the data after cleaning,a more accurate model can be established,which is significant to the subsequent temperature control.The conversion rate of SO_(2) can be further improved,thereby improving the yield of sulfuric acid and economic benefits. 展开更多
关键词 acid production Data cleaning Isolation forest Random forest Data compensation
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The Spillover Effect between Futures and Spot Price of Agricultural Products:A Case Study of Soybean Products of China 被引量:2
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作者 Kai ZHAO 《Asian Agricultural Research》 2017年第3期24-28,33,共6页
Taking soybean products as an example and using the daily price data of 2007-2015,this paper established the error correction model and BEKK-GARCH model,and made an empirical study on the spillover effect of futures a... Taking soybean products as an example and using the daily price data of 2007-2015,this paper established the error correction model and BEKK-GARCH model,and made an empirical study on the spillover effect of futures and spot price of agricultural products of China. According to this study,there were mean spillover effect and two-way volatility spillover effect in futures and spot price of soybean,soybean oil,and soybean meal; soybean futures prices significantly guided the spot price; in the price linkage between the types,the price relationship between the soybean meal and soybean was closer than between the soybean oil and soybean. 展开更多
关键词 Futures price Spot price Soybean products Volatility spillover price linkage
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Quantifying the effect of persistent dryer climates on forest productivity and implications for forest planning:a case study in northern Germany 被引量:1
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作者 Matthias Albert Ralf-Volker Nagel +1 位作者 Johannes Sutmoller Matthias Schmidt 《Forest Ecosystems》 SCIE CSCD 2018年第4期451-471,共21页
Background: Forest management decisions are based on expectations of future developments. For sound decisions it is essential to accurately predict the expected values in future developments and to account for their i... Background: Forest management decisions are based on expectations of future developments. For sound decisions it is essential to accurately predict the expected values in future developments and to account for their inherent uncertainty,for example the impact of climate change on forests. Changing climatic conditions affect forest productivity and alter the risk profile of forests and forest enterprises. Intensifying drought stress is seen as one major risk factor threatening forest management in the north German lowlands. Drought stress reduces tree growth and vitality and might even trigger mortality. But so far, it is not possible to quantify effects of a persistent dryer climate on forest productivity at a level suitable for forest management.Methods: We apply a well-established single-tree forest growth simulator to quantify the effect of persistent dryer climates on future forest productivity. We analyse the growth of Scots pine(Pinus sylvestris L.), European beech(Fagus sylvatico L.) and oak(Quercus robur L. and Quercus petraea(Matt.) Liebl.) in two forest regions in the north German lowlands for a time interval of 60 years until 2070. The growth response under three different climate projections is compared to a baseline scenario.Results: The results show clear differences in volume increment to persistent dryer climates between tree species. The findings exhibit regional differences and temporal trends. While mean annual increment at biological rotation age of Scots pine and oak predominantly benefits from the projected climate conditions until 2070, beech might suffer losses of up to 3 m^3·ha^(-1)yr^(-1) depending on climate scenario and region. However, in the projection period2051 to 2070 the uncertainty ranges comprise positive as well as negative climatic effects for all species.Conclusions: The projected changes in forest growth serve as quantitative contributions to provide decision support in the evaluation of, for example, species future site suitability and timber supply assessments. The analysis of productivity changes under persistent dryer climate complements the drought vulnerability assessment which is applied in practical forestry in northwestern Germany today. The projected species' productivity has strong implications for forest management and the inherent uncertainty needs to be accounted for. 展开更多
关键词 Climate change forest growth forest productivity Persistent dryer climate simulation study Uncertainty
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Empirical Study on the Impact of Rural Labor Force Flow on the Price of Agricultural Products——A Method Based on VEC Model 被引量:2
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作者 WEN Li 《Asian Agricultural Research》 2010年第7期25-29,共5页
Based on the research introduction of domestic and foreign scholars,dynamic equilibrium between the rural labor force flow and the price of agricultural product is analyzed by VEC model,according to the data of the ru... Based on the research introduction of domestic and foreign scholars,dynamic equilibrium between the rural labor force flow and the price of agricultural product is analyzed by VEC model,according to the data of the rural labor force flow and the price of agricultural products in the years 1990-2007.Chows breakpoint test is used to measure the stage characteristics of the impact of rural labor force flow on the price of agricultural product.Result shows that there is a long-term and stationary relationship between the flow quantity of rural labor force and the price of agricultural product.Rural labor force flow,as an exogenous force,affects the agricultural production,and further influences the price fluctuation of agricultural products.Impact of rural labor force flow on the price of agricultural product is from weak to strong,then grows gradually weaker,and reaches its peak value at the year 1998.With the development of rural society and economy and the market process,rural labor force flow endogenously affects the price of agricultural product,which has periodic characteristics.In order to achieve a dual stabilization of the rural labor force flow and the price of agricultural products,the following countermeasures are put forward:vigorously developing vocational education,increasing the support for agricultural production,and making active employment measures. 展开更多
关键词 Rural labor force flow price of agricultural products VEC model Vocational education China
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A review on the use of non-timber forest products in beauty-care in Bangladesh 被引量:2
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作者 Sayma Akhter Md. Abdul Halim +3 位作者 Md. Shawkat Islam Sohel Swapan Kumar Sarker Mohammad Shaheed Hossain Chowdhury Sanjay Saha Sonet 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第1期72-78,共7页
This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and u... This review describes the non-timber forest products (NTFPs) used for different aspects of beauty-care in Bangladesh on the basis of extensive literature survey. The diverse plant species, including used parts and using patterns for hair care, facial treatments and body care, were summarized in 13 tables. This paper accumulate the scattered knowledge regarding the use of plants in beauty-care in Bangladesh, to draw the extent of use of NTFPs in health care and to record the knowledge for assessing the possibilities of further implementation in herbal cosmetics industries. The structured knowledge can be used in policy making process for sustainable management of these valuable NTFPs leading to the conservation of the country's biological diversity. It is suggested that intensive field level research is necessary for securing sustainability of NTFPs. 展开更多
关键词 beauty care non-timber forest products (NTFPs) BaNGLaDESH
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Effects of harvest intensity on the marketable organ yield,growth and reproduction of non-timber forest products(NTFPs):implication for conservation and sustainable utilization of NTFPs 被引量:1
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作者 Ting Zhang Lizhong Yu +1 位作者 Yuan Man Qiaoling Yan 《Forest Ecosystems》 SCIE CSCD 2021年第4期755-764,共10页
Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic... Background:Non-timber forest products(NTFPs)are an important part of forest biodiversity,and the subsistence and trade of local people,especially in less developed countries.Because of the high ecological and economic value,NTFPs have faced the problem of over-exploitation,and the key to solve this problem is to determine the feasible way of sustainable utilization of NTFPs.Harvest intensity is one of the most important and easily controlled utilization factors,which can greatly influence the plant individual survival,growth and reproductive performances,and even the population structure and dynamics.Therefore,we chose two common and important NTFPs species with different marketable parts(i.e.,Acanthopanax senticosus with tender leaves and Aralia elata with tender buds)as our study objects.Aiming to determine the optimum harvest intensity for sustainably utilizing both NTFPs species,five levels of harvest intensity treatments(i.e.,control,light,medium,high and severe)were designed to assess the effects of harvest intensity on their marketable organ yield,plant growth and reproductive performances.Results:The biomass growth rates of marketable organ and plant growth of A.senticosus under light harvest intensity treatment were significantly higher than those under other harvest intensities.The plant height growth and 1000-seed weight of A.elata under severe harvest intensity treatment were significantly lower than those under control treatment.Conclusions:The light harvest intensity with 25% leaf removal and the high harvest intensity with all terminal buds harvested are the optimum harvest intensity to maintain the sustainable utilization of A.senticosus and A.elata,respectively.These findings could provide managers with basic but practical guidance for making decisions about the sustainable harvest management plan for the cultivated NTFPs species,and further provide a theoretical basis for managers to establish the harvest regulations for wild NTFPs species.Consequently,the local residents or communities can improve their income while ensure the sustainable development of wild NTFPs. 展开更多
关键词 araliaceae family Non-timber forest products Sustainable utilization Harvest intensity Plant regeneration Marketable organ yield
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Contribution of non-timber forest products to the livelihoods of the forest-dependent communities around the Khadimnagar National Park in northeastern Bangladesh 被引量:1
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作者 Md.Habibur RAHMAN Bishwajit ROY Md.Shahidul ISLAM 《Regional Sustainability》 2021年第3期280-295,共16页
Non-timber forest products(NTFPs)play a significant role in the improvement of the forest-dependent people’s livelihoodsaround the world,strengthening protection for the sustainable use of forests.The purpose of this... Non-timber forest products(NTFPs)play a significant role in the improvement of the forest-dependent people’s livelihoodsaround the world,strengthening protection for the sustainable use of forests.The purpose of this research was to evaluate the influence of occupational category-wise(fuelwood collectors,farmers,small-scale businessmen,day labourers,and tea estate labourers)dependencyon NTFPsand the role of NTFPs on household income around the Khadimnagar National Park(KNP)in northeastern Bangladesh.In 2014,178purposively selected respondents from four villages(out of 22 villagesaround the KNP)were interviewed face-to-face using a semi-structured questionnaire.The study observed that these forest-dependent communities utilized resources of the KNP mainly for domestic energy supply,household income,and house construction.Results showed that income from NTFPs made a significant contribution to family income.Income data analysis indicated that small-scale businessmen earned relatively more income from NTFPs,followed by tea estate labourersand day labourers.The study revealed significant negative relationships of the distance of households from the forest with the amount of NTFPs collected(P<0.01)and monthly income from NTFPs(P<0.01).Positive significant relationships were found between the amount of NTFPs collected and the time spent in NTFP collection(P<0.001),as well as betweenmonthly income from NTFPs and family size(P<0.001).The fuelwood collectors and farmers collected significantly greater amounts of NTFPs per trip(P<0.001)than other occupational categories.The households that were moderately to highly dependent on NTFPs collected significantly higher amounts of NTFPs pertrip(P<0.01)than the households that were moderately dependent and less dependent on NTFPs.Community dependence on KNP’sresources,community’sappreciation of the KNP’s ecosystem services for villagers’livelihoods,and community’s high levels of concern for forest conservation provided a foundation for the sustainable management of the KNP.The study findings will be useful for designing an effective forest management plan and policy for NTFP management and forest conservation with the active involvement of the forest-dependent people in northeastern Bangladesh. 展开更多
关键词 forest dependency Household income Non-timber forest products forest sustainability Occupational categories Khadimnagar National Park
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Evaluation of the Land Production Potential in the Context of Returning Farmland to Forest in Karst Region:A Case Study of Guizhou Province 被引量:2
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作者 Shuang YU Guang LI Ruiping RAN 《Asian Agricultural Research》 2013年第1期21-26,共6页
In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test ... In this paper, we take Guizhou Province (the heart of southwestern Karst region in China) as the research object. By establishing gray forecasting model and time series forecasting model, we conduct the accuracy test on the actual production capacity of land and the forecasted production capacity of land in 2007 and 2008, and then conduct comprehensive forecast of the land production potential in Guizhou Province in 2020. On this basis, considering the nutritional standards needed by three kinds of life type (dressing warmly and eating one's fill, well-off life, relatively affluent life), we evaluate the land production potential in Guizhou Province under the project of returning farmland to forest. Based on the evaluation results, we put forth the relevant recommendations for achieving sustainable land use in the context of returning farmland to forest in Guizhou Province. 展开更多
关键词 KaRST region Project of RETURNING FaRMLaND to fore
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Discussion on the Concept of Forest Public Product Based on the Relationship of Modern Population, Resource and Environment
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作者 Changchun ZHOU Enguang ZHANG 《Asian Agricultural Research》 2013年第5期105-107,共3页
Based on the unbalanced relationship among modern population, resource and environment, as well as the weak awareness and supply-demand conflict of forest public product, the paper exposed the public product function ... Based on the unbalanced relationship among modern population, resource and environment, as well as the weak awareness and supply-demand conflict of forest public product, the paper exposed the public product function of forestry and explained its meaning, then evaluated the traditional concepts of forestry, product, and forest products, and finally redefined the extension of forest products. On this basis, the concepts of forestry and public products were elaborated, and the connotation, characteristics and extension of forest public products were clearly defined and described. 展开更多
关键词 forestRY forest product PUBLIC product forest publ
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International Comparison,Regional Characteristics and Regulatory Management of Structural Rise in the Prices of Chinese Industrial and Agricultural Products
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作者 Ming ZHANG Hong TAN +1 位作者 Ran AN Zhibo ZHOU 《Asian Agricultural Research》 2014年第4期1-4,9,共5页
China's price fluctuations increasingly exhibit significant structural characteristics,and since 2003,there have been several rounds of significant structural price rise.The degree of structural rise in the prices... China's price fluctuations increasingly exhibit significant structural characteristics,and since 2003,there have been several rounds of significant structural price rise.The degree of structural rise in the prices of industrial and agricultural products in China is not only higher than in the general developed countries and developing countries,but also more prominent than in other transition economies.And the structural rise in the prices of Chinese industrial and agricultural products exhibits significant economic zone differences:the structural fluctuations are the greatest in the central and western regions,significantly higher than in the eastern regions as well as the national average.From the perspective of causes of structural rise in the prices of Chinese industrial and agricultural products,the government must aim to coordinate the industrial and agricultural investments and bridge the gap in the industrial and agricultural technologies and supply capacity. 展开更多
关键词 the priceS of INDUSTRIaL and agricultural products
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The Price Model of Aquatic Products Based on Predictive Control Theory
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作者 LIU Jing China Agricultural University, Beijing 100083, China 《Asian Agricultural Research》 2011年第12期19-22,27,共5页
This paper discusses a disequilibrium cobweb model of price of aquatic products, and applies predictive control theory, so that the system operates stably, and the deviation between supply and demand of aquatic produc... This paper discusses a disequilibrium cobweb model of price of aquatic products, and applies predictive control theory, so that the system operates stably, and the deviation between supply and demand of aquatic products smoothly tracks the pre-given target. It defines the supply and demand change model, and researches the impact of parameter selection in this model on dynamic state and robustness of the system. I conduct simulation by Matlab software, to get the response curve of this model. The results show that in the early period of commodities coming into the market, affected by lack of market information and many other factors, the price fluctuates greatly in a short time. The market will gradually achieve balance between supply and demand over time, and the price fluctuations in the neighbouring two periods are broadly consistent. The increase in model parameter can decrease overshoot, to promote the stability of system, but the slower the dynamic response, the longer the deviation between supply and demand to accurately track a given target. Therefore, by selecting different parameters, the decision-makers can establish different models of supply and demand changes to meet the actual needs, and ensure stable development of market. Simulation results verify the excellent performance of this algorithm. 展开更多
关键词 aQUaTIC productS price Supply DEMaND PREDICTIVE co
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The influence of price on rice production in Sierra Leone
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作者 Alhaji Mohamed Hamza Conteh Xiangbin Yan Foday Pinka Sankoh 《Agricultural Sciences》 2012年第4期462-469,共8页
Rice is the main staple food of the vast majority of Sierra Leoneans, eaten on a daily basis by almost every household in the country. Rice is the most important food crop widely grown by farmers across the country. A... Rice is the main staple food of the vast majority of Sierra Leoneans, eaten on a daily basis by almost every household in the country. Rice is the most important food crop widely grown by farmers across the country. Although much attention is now focused on rice production through the small holder commercialization programme (SHCP), less attention has been given to investigating the constraints faced by rice producers in the country. Also, as food insecurity continues to be a major development problem across the country, thereby undermining people’s health, productivity, and often their very survival;this study contributes to efforts to overcome the development challenges posed by food insecurity necessarily begin with accurate assessment of influential factors that constrained the production of the staple food, rice. The main objective of this study is therefore to analysis the factors that influence rice production in the country, and specifically examine the relationship between rice production and the price of rice as sold in the domestic market. The study used a log linear model with the quantity of rice produced as the dependent variable and the price of domestic rice, quantity of rice imported and price of imported rice as explanatory. Findings indicated that, domestic rice is more expensive than imported rice per ton, and this underscores the argument that, rice importation is undermining domestic rice production as a viable income generating activity. Also, almost all the people in the capital city which hosts about 70% of the total population of country prefer eating imported rice, since it is free from stones and other impurities. However, In order to control price and still increase rice production, the government should be able to purchase the rice from the farmers and then sell this rice to private retailers. 展开更多
关键词 Sierra Leone FOOD SECURITY RICE production Econometric Model Specification price of DOMESTIC RICE
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Ecologically-Based Production Systems: Production of Banana in the Atlantic Forest in the State of Rio Grande do Sul Brazil
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作者 Daniela Garcez Wives Carlos Mielitz Net-to +2 位作者 Carolina Castilho e SilvaI Luciano Figueiredo Janaina Aragao 《Journal of Environmental Science and Engineering(A)》 2013年第9期575-581,共7页
This paper analyzes the performance and operation of ecologically-based production systems in the Atlantic Forest in southern Brazil in an integrated approach to their multifunctional characteristics and rural develop... This paper analyzes the performance and operation of ecologically-based production systems in the Atlantic Forest in southern Brazil in an integrated approach to their multifunctional characteristics and rural development. Nowadays the Atlantic Forest is considered the most threatenet biome, because of exploitation of their biological resources and unsuitable agricultural purposes. Banana cultivation is one of biggest commercial productions in atlantic south portion of forest, showing two different cropping systems: one using conventional management tehniques and other antagonistic, ecological based. The ecological system is compatible with the conservation of sustainable use of forests. The article presents a comparative analysis-diagnosis of major production and cultivation systems of banana, using the production systems approach, with evaluation of economic and technical indicators. The database is composed by 17 interviews conducted under field conditions in 2007. As a result, the technical and economic functioning of ecological systems demonstrate achieve economic efficiency, in general, higher than conventional systems. Furthermore, some key characteristics of ecological based systems focus on food production and income generation for farmers without harming areas of the Atlantic Forest, being in equilibrium with tropical dynamic and being an important instrument for the restoration of degraded ecosystems and for local development. 展开更多
关键词 Ecologically-based production systems banana production atlantic forest.
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Price Discrimination of Film Products and Building of Hierarchical Market under the Background of “Internet Plus”
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作者 Zhang Libo Hu Yan 《Contemporary Social Sciences》 2016年第2期129-136,共8页
Price Discrimination of film products is theoretically feasible and logically inevitable, and it has been used for a long time in film industry as well. However, there are practical paradoxes in the new environment du... Price Discrimination of film products is theoretically feasible and logically inevitable, and it has been used for a long time in film industry as well. However, there are practical paradoxes in the new environment due to market factors like popularization of Internet environment and Online to Offline(O2O) retailers between hierarchical markets. Compared with high-level markets, low-level markets are lack of conditions for differentiated lower price like cinema infrastructure, and environment for film consumption market, so that the consumption potential for market has not been motivated yet. Therefore, it is quite important to pay close attention to how to expand the market by clearer gradient pricing structures and Internet platform. 展开更多
关键词 price discrimination FILM productS demand elasticity INTERNET PLUS HIERaRCHICaL MaRKET
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Impacts of the Benefit Sharing Mechanism(BSM)Policy Implementation on Forest Protection and Sustainable Use of Non-timber Products at Bach Ma National Park
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作者 Nguyen Van Loi Nguyen Vu Linh 《Journal of Agricultural Science and Technology(A)》 2017年第B10期68-77,共10页
This study aimed to evaluate the impacts of the benefit sharing mechanism(BSM)pilot policy on sustainable use of non-timber forest products(NTFPs)and natural resources conservation in co-management forest of Bach Ma N... This study aimed to evaluate the impacts of the benefit sharing mechanism(BSM)pilot policy on sustainable use of non-timber forest products(NTFPs)and natural resources conservation in co-management forest of Bach Ma National Park.Evaluation methods were route and permanent plot survey,household interview,in-depth interview,village meeting,group discussion and workshop at commune level.Results showed that:(1)the BSM policy had brought favorable conditions for local people in sustainable use and development of the NTFPs,as well as minimised the threats to biodiversity in co-managed forest;(2)the harvest amounts of seven selected NTFPs after two years of the BSM policy implementation were higher than growth rate of every NTFP and the permitted harvest amounts of the benefit sharing plans(BSP);(3)although there was a risk of over-exploitation of the NTFPs,the annual yields in 2013 and 2014 were much lower,but more sustainable than that before the BSM implementation;(4)the forest protection status in the co-management areas was also better than before.Additionally,this study has also defined and recommended that in order to continue the BSM,it is necessary to ensure the sustainable exploitation of NTFPs,as well as implement more enforcement activities inside the co-management forest area. 展开更多
关键词 BSM policy CO-MaNaGEMENT non-timber forest products BaCH Ma National Park protection and SUSTaINaBLE use
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