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1.
A homestead is an integrated production system where trees, crops, livestock and poultry are found in and around the household residence in Bangladesh. It is a potential production unit that provides various product, service and ecological functions. Almost all people in Bangladesh including landless households have homesteads in which they grow trees and crops even in a small piece of land. This study characterizes the species composition, diversity and productivity of the homestead production system in the Teknaf peninsula, southeastern Bangladesh. Survey data collection was from a total of 180 homesteads covering five household categories: large, medium, small, marginal and landless. Vegetable, fruit, timber, and livestock and poultry were common components in the homestead production system. Various types of plants were mainly concentrated in back yards, front yards, boundaries and corners of homesteads. The mean number of tree species per homestead was about 15. In total, 189 tree and shrub species were recorded, and were distinctly high and low in the large (363.7) and landless (55.7) household categories. Species composition, diversity and productivity of homesteads were found to be related to household categories. Richness and diversity of tree and shrub species increased with household size. Betel nut was the dominant tree species followed by mango, jackfruit and coconut. Annual income from homesteads also varied among the household categories, with a mean contribution of the homestead to annual income of about 25 %. A large portion of homestead income came from betel nut trees. There is scope to increase species diversity and income by designing homesteads with the engagement of women and other family members.  相似文献   

2.
Woody plants diversity and possession in small-scale tree and shrub growing practices among farmers of central highland Ethiopia were assessed by using a complete census of the trees and shrubs existing on farmers’ lands. The future prospects of diversity and possession of woody plants in the agricultural landscapes were also investigated by using the farmers’ species preferences and seedling demands as indicators. Comparisons were made across wealth classes, proximity clusters to a nearby state forest and land uses. It was found that 27 tree and 21 shrub species exist on lands of the studied households. With increasing wealth status of the households, the tree and shrub species richnesses increased. Tree and shrub species richnesses were highest in boundary plantings and homesteads respectively. Small-scale woodlots had the highest number of tree stems while homesteads contained the highest number of shrub stems. The number of tree stems a household possesses is strongly influenced by distance from the state forest, family size, educational level of the household head and number of iron-roofed houses owned. And, the shrub stems possession is significantly influenced by wealth status, distance from the state forest, land holding size, family size, livestock holding, age of wife and possession of off-farm income sources. The species preference analysis and seedling demand computations indicated that the woody species diversity is less likely to change in the future because there is no difference between the currently existing species and the preferred ones. Nonetheless, the number of tree and shrub stems on the farmers’ holdings could increase if the seedling demands of the preferred woody species are met.  相似文献   

3.
Bukoba district is located in the north-western part of Tanzania and its economy is predominantly agricultural. Banana and coffee are, respectively, the most important food and cash crops. Population density is very high (500–1250 persons per km2 of cultivated land) and so is the pressure on land and other natural resources. Farm holdings (homegardens) are mostly smaller than a hectare and continue to fragment as population continues to grow. A homegarden is locally known as Kibanja and it is both a social and economic unit of farm families in the district. Various crops, trees, shrubs, herbs and livestock are managed on the same piece of land mainly by family labour to provide food, cash, medicine, shade, poles, timber and some socio-cultural functions. This paper describes the homegarden agroforestry farming system of Bukoba, evaluates its viability and identifies critical constraints as well as research needs.  相似文献   

4.
Integrated management of natural resources and the multiple use of trees and forests have prevailed in most European societies since prehistoric times. In the Middle Ages, expanding and intensified agriculture resulted in the separation of trees from agricultural fields. During the last century, with the introduction of sustainable and highly productive forest management, the goal of increased wood production has been achieved in most parts of central, northern, and eastern Europe. Today, agroforestry is not considered to be an important land-use option within the region; however, there are many practices that could rightfully be classified as agroforestry. These include tree/crop systems in which trees provide products and/or environmental benefits, and tree/animal systems in which animals are grazed in forests or open woodlands.The future seems to offer some prospects for agroforestry. Large areas, hitherto used for food production, are either marginally suited to agriculture, or will probably be taken out of production due to agricultural policy considerations. Agroforestry may, at least in part, offer alternatives for the use of such lands. The availability of (surplus) fertile soils, capital, and labor may provide incentives for site-adapted forms of agroforestry, including improved fallow management. The focus of such systems would be on maintenance of biodiversity in the landscape, environmental protection, recreation, and product diversification.There are numerous expectations as to what agroforestry might provide for the land holder and for society as a whole. These expectations should be carefully analyzed and evaluated prior to political decisions on future land use. The promotion of agroforestry requires overall investment; agroforestry does not happen by itself. A set of integrated actions — not isolated efforts — must be implemented if agroforestry is to become a successful land-use option.  相似文献   

5.
A general classification of agroforestry practice   总被引:1,自引:0,他引:1  
Present classification schemes confuse agroforestry practices, where trees are intimately associated with agricultural components at a field scale, with the whole farm and forest systems of which they form a part. In fact, it is common for farming systems to involve the integration of several reasonably discrete agroforestry practices, on different types of land. The purpose of a general classification is to identify different types of agroforestry and to group those that are similar, thereby facilitating communication and the organized storage of information. A new scheme is proposed that uses the ‘practice’ rather than the ‘system’ as the unit of classification. This allows an efficient grouping of practices that have a similar underlying ecology and prospects for management. A two stage definition of agroforestry is proposed that distinguishes an interdisciplinary approach to land use from a set of integrated land use practices. Four levels of organization are recognized through analysis of the role of trees in agricultural landscapes: the land use system, categories of land use within systems, discrete groups of components (trees, crops, animals) managed together, and functionally connected groups of such discrete practices in time and space. Precedents for this form of analysis are found in the literature and it conforms with generally accepted methods of systems analysis. Classification of major types of agroforestry practice proceeds primarily according to the components involved and the predominant usage of land. A secondary scheme further classifies these in terms of the arrangement, density and diversity of the tree components involved. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

6.
The role of shelter in Australia for protecting soils,plants and livestock   总被引:4,自引:0,他引:4  
The purpose of this review is to examine the current knowledge of the role of trees in providing shelter for pastures, crops, and livestock, for controlling erosion of soils and improving productivity and sustainability of agricultural production in Australia — and the extent to which this knowledge has been applied.Land degradation — tree loss and associated soil salinity, water and wind erosion, soil acidification, soil structural decline and nutrient degradation — is evidence that our primary production systems are not sustainable. We have sought increased production without proper consideration of the ecological context of that system. About half of Victoria's crop and pasture lands are affected or at risk, and in Western Australia about 25% of the cleared agricultural land is wind-eroded and 60% is potentially susceptible, salinity affects 0.43 m ha and half of the divertible surface water is affected by salinity. Similar problems occur in other States. At least 43 m ha or 13% of our rangelands are seriously degraded by wind erosion caused by overgrazing, often coinciding with drought or a run of drier years.Minimum tillage and stubble management for erosion control in cropping has been a major extension and research activity in Australian agriculture. Severe weather, combined with imperfect adoption of appropriate grazing and crop management systems, shows the weakness of complete reliance on these methods of erosion control. An effective system must accommodate the impact of extreme events, which are the most damaging. However, the complementary use of windbreaks to reduce soil erosion is rare, and their establishment has not been promoted, despite the wide-spread adoption of this technology by other countries.In the cropping and higher rainfall grazing areas, the systematic planting of 10% of the land in a net of shelterbelts/timberbelts/clusters could achieve a 50% windspeed reduction; this would substantially improve livestock and pasture production in the short and long-term. Wind erosion could be dramatically reduced and crop production probably increased by the use of windbreaks. Wheat and oat yield at Rutherglen (Victoria), and lupin yield at Esperance (Western Australia), were increased in the sheltered zone by 22% and 47%, and 30%, respectively.In semi-arid and dry temperate areas, planting of 5% of the land to shelter could reduce windspeed by 30–50% and soil loss by up to 80%. This planting would also contribute substantially to achieving other objectives of sustainable agriculture. Agroforestry — particularly timberbelts applications — will be important in the long-term strategy for achieving revegetation. If some of the trees yield a marketable product then the adoption of the system will be more readily achieved.In the arid (pastoral) areas there is an urgent need to promote the ethic that preservation and improvement of the perennial grass and shrub vegetation is critical for the protection of the soil and maintenance of land capability. Control of animal grazing remains the sole means of preventing erosion in much of this zone. While satellite imagery allows us to assess the condition of leasehold lands, we have failed to achieve stocking policies that will halt the degradation of our rangelands.  相似文献   

7.
A survey was conducted in 17 selectedthaluks (revenue sub-divisions) of Kerala state to elucidate the floristic structure, composition and the extent of similarities and diversities in the composition of homegardens of Kerala, with particular reference to small (below 0.4 ha), medium (0.5 to 2 ha) and large (>2.0 ha) holding size categories. Besides attempts wer also made to characterize the potential of homegardens to supply commercial timber and fuelwood. Two hundred and fifty two farmers were selected through a stratified random process. In addition to gathering general information on crop and livestock production enterprises, all scattered trees and shrubs (15 cm girth at breast height) on the homestead and border trees except palms and rubber were enumerated.There was tremendous variability both in the number of trees and shrubs present and species diversity of the selected homesteads in different provinces. The small, medium and large sized holdings also exhibited profound variability in the number of woody taxa and individuals present. In total, 127 woody species (Girth at Breast Height (GBH) 15 cm) were encountered. The mean number of woody taxa found in the homegardens ranged from 11 for Pathanapuram to 39 in Perinthalmanna. Floristic diversity was higher in the smaller homesteads. It decreased with increasing the size of holdings. Mean Simpson's diversity index for the homesteads ranged from 0.251 (Kochi) to 0.739 (Kottarakkara) suggesting that floristic diversity of homegardens was moderate to low compared to a value over 0.90 for the species-rich evergreen forests of the Western Ghats. The Sorensen's similarity indexes suggested a moderately high degree of similarity for the different tree species encountered in the homesteads of Kerala.No clear cut planting pattern was discernible in the homegardens of Kerala. The homegarden trees and shrubs were either scattered throughout the homestead or on farm boundaries. Farmers tend to prefer timber trees such as ailanthus (highest frequency) and teak besides fruit trees such as mango, jack, cashew and the like. Major homegarden species were represented in all diameter classes. The diameter structure, however, exhibited a slightly skewed (+) distribution pattern, having the highest frequency in the 20–30 cm classes ensuring adequate regeneration status and in that process making homegardens a sustainable as well as dynamic land use system.Standing stock of timber and firewood in the homestead of differentthaluks are presented. Average commercial standing stock of homesteads ranged from 6.6 to 50.8 m3 ha–1 and fuel wood volume was of the order of 23 to 86 m3 ha–1. Implicit in the high commercial timber volume and fuel wood volume is that a substantial proportion of the society's wood demands are met from the homesteads. Palms, however, constituted the dominant component of standing commercial timber and fuel wood volumes accounting as much as 63% and 72%, respectively, of the total wood in these categories.  相似文献   

8.
Hillside farming with its attendant erosion and decline in soil fertility is common-place in the area served by the Farming Systems Improvement Project. The project is designing land-use systems that would check erosion, increase soil organic matter and restore soil fertility. These systems will allow small farmers to increase or maintain product long-term basis without resorting to the use of high doses of inorganic fertilizers which are not readily available in the country. The use of leguminous shrubs and cover crops as nutrient sources — concepts embodied in agroforestry and organic farming systems — are options that landuse experts think might solve the problem. However, there is a dearth of knowledge about the biological feasibility of these interventions in the project area.This paper reports how FSIP combined problem diagnosis and analysis, researcher-managed adaptive trials and a field day to attack this lack of information. The rationale for using this approach is to address farmers' real needs, save time and minimize risk to poor farmers.This article is a contribution from the University of Arkansas' USAID-supported Farming System Improvement Project (FSIP) in Rawanda (USAID 696-0110), B.P. 625, Kigali, Rawanda. Authors are the project's soil scientist/agronomist and its extension and training specialist respectively.  相似文献   

9.
In the Philippines, timber production on small farms has become profitable as a result of reduced supplies due to extensive deforestation and increasing demand. In the early 1990s, when the price of timber was high, farmers were promised huge returns from tree farming. However, widespread planting of few species has led to oversupply and a sharp decline in the price of farm-grown timber. Moreover, low intercrop yields as a result of competition from fast-growing trees and low timber yields due to poor tree management, further reduce net economic returns. In spite of this, interest in tree farming remains high. This paper examines the private profitability of two tree-maize systems, namely trees in blocks and trees in hedgerows, compared with the alternative of maize monocropping. The analysis reveals that maize monocropping provides higher returns to land at the current timber price, but considerably lower returns to labour, than the maize-tree systems tested. This suggests that tree farming is a more attractive option for labour and capital-constrained households or those with off-farm opportunities that compete for their labour. These farmers may raise productivity and income by planting trees on the excess land that cannot be devoted to annual crops. The analysis also indicates that wide-spaced tree hedgerows are superior to tree blocks, due to lower establishment and management costs, longer periods of viable intercropping and more rapid tree growth.  相似文献   

10.
Tree growing by smallholder farmers is an emerging livelihood strategy in Lake Tana catchment. The objectives of this study were to (1) identify the most important tree species grown, (2) investigate the drivers of the existing pattern, and (3) identify determinants of the number and diversity of tree species and their spatial patterns. Survey data were collected from 200 households. Multiple linear regression was employed to identify the determinants of tree growing behaviour of households and spatial variables affecting the abundance of tree species. Eucalyptus globulus, Acacia decurrens and E. camaldulensis dominate woodlots. Only a fraction of the forest production is used by the households, the rest being sold as poles or charcoal. Location in relation to market centres, number of livestock owned, landholding size and age of household head were found to positively affected the number of tree species and trees grown. Gender affected the species and spatial pattern of trees. Woodlots, farm boundaries and homesteads were found to be important tree growing niches. These results substantiate the proposition that farmers assign their parcels of land to uses that increase the rent value of the land, and this value is affected by access to roads. Woodlots are on the increase at the cost of productive agricultural land. Provision of a tree planting extension service may increase participation of farmers in tree planting, and a management-oriented tree planting extension service may give desirable results.  相似文献   

11.
Summary Wild animal damage in Poland and possibilities of limiting it by chemicals.The uncontrolled increase of wild animals, due to the war and the following time caused a high wild animal damage to crops and trees in Poland. On the strength of new game-laws (1952 and 1959) the Polish wood land was parcelled into hunting-grounds of 3–8000 ha, which were let to the hunting associations. The amounts of maximal density of wild animals ordered by game-laws are the following: red deer 5 (woods with poor nutriments) — 15 (rich nutriments), roe deer 25–75 and fallow deer 10–30 individuals per 1000 ha.But regulating the number of deer didn't decrease wild animal damage sufficiently. Besides it is necessary to use chemicals (repellents), which have to be absolutely harmless for men, wild animals and ecosystems. Due to the lack of workmen the repellents must be applied mechanically.The Institute of Plant Protection of Poznan is testing own and foreign preparations for their effectiveness.Up to now two preparations (one fabricated in BRD and the other in DDR) were found to be suitable.  相似文献   

12.
This review encompasses results of fertilization experiments on several agroforestry systems—alley cropping, perennial shade systems, home gardens—in which fertilizer use is a likely management alternative. Fertilizer response was found to be most common in alley cropping, variable in perennial shade systems, and rarely reported in home gardens. Level of nutrient removal in harvested products is probably the overriding factor in determining fertilizer response; greater accumulation of organic residues, slower growth under shade, and longer periods of nutrient uptake probably also contribute to the relatively smaller fertilizer response of the perennial shade systems and home gardens. Considerable knowledge gaps exist regarding the breakdown of organic residues, and interactions between mineral and organic amendments. Systems based on annual crops (e.g., alley cropping) are likely to be less nutrient-efficient and sustainable than systems based on perennial crops, due to reduced fixation and transfer of N to the crops, the tendency of the trees to compete for and sequester nutrients, relatively high P requirements of the crops, and the high labor cost of tree management. The possible benefits of fertilization of specific components in home gardens, and relative advantages of including low-value tree legumes, high-value shade trees, and fertilization in shaded perennial systems are only beginning to receive research attention.  相似文献   

13.
The developing countries of the Pacific Region consist of 27 countries and territories with a total nd area of 542 000 km2 and over 5 million inhabitants. Though highly variable in physical characteristics and land-use pattern, these countries, in general, give a higher priority for production of export crops over other agricultural crops, so that they are net importers of food. Natural forests of the region are luxuriant and floristically rich, but the level of their commercial exploitation is low. Swidden cultivation is the mainstay of subsistence livelihood, but with the increase in population, the system is now causing severe environmental and land-use problems.The major agroforestry systems and practices in the region include various forms of combination of tree crops such as coffee, coconut and cacao with nitrogen fixing trees such as Casuarina, Gliricidia and Leucaena, and food crops (mostly tubers) such as cassava, taro, sweet potato and yams. Additionally, some improvements to swidden (shifting) cultivation are also being tried in several places, the most common being the u use of Casuarina oligodon before abandoning the swidden as in PNG highlands, and intercropping food crops in tree crop stands.Land tenure system in most of the countries is the traditional clan of extended family control over land. This can have either positive or negative influence on the adoption of agroforestry practices depending on the extent and duration of tenancy tenure enjoyed by the assignees of land.Several governments of the region are now promoting the agroforestry approach. In hilly areas with poor access, farmers are forced to produce most of their basic necessities locally. On the other hand, the lack of roads and communication facilities can pose a problem in marketing any surplus products they have.The immediate opportunity in agroforestry in the region lies in making better use of the unexplored potential of a large number of locally available trees and agricultural crops. Intercropping in tree crop stands and the taungya system seem to propromising m methods for the Pacific region.Researh Fellow, July–September, 1984  相似文献   

14.
Roots of trees (Sesbania sesban) and crops (Zea mays) were quantified during two tree/crop cycles in a sequential tree — crop system at Chipata, Eastern Zambia. The experiment included one- and two-year fallows as well as fertilized and unfertilized controls. The roots of S. sesban represent a standing biomass in the soil of 3 Mg hat-1 in the top 1.5 m after two years, with 45–60% and 70–75% being in the top 25 and 50 cm respectively. S. sesban fallow improved early rooting and growth of the following maize crop. Increased soil infiltration was also observed in the two-year fallow treatment, as well as decreased bulk density and resistance to penetration in the soil. No differences between maize root parameters could be detected at tasselling, nor differences between nutrient status of the different treatments. Study results indicate that under the drought-prone conditions of Eastern Zambia, where improved soil physical conditions are important for early deep rooting of crops and access to water and nutrients, tree roots could play an important role in the fallow effect. Further studies are required to assess the relative importance of the improvement of soil chemical and physical properties.Submitted as ICRAF Journal Article # 95/28.  相似文献   

15.
Hedgrow intercropping (alley cropping) is a relatively new technology involving growing agricultural crops between rows of planted tree species. Leucaena is the most widely studied tree species for the practice and research has indicated that it can yield over 200 kg ha–1 year–1 of nitrogen for application in the alleys where crops are planted. More herbage (and nitrogen) are obtained from narrow alleys, and crops utilise the nitrogen better if the prunings are incorporated into the soil before planting. Low pruning heights may prevent shading of the crops.Most of the agronomic aspects of the practice have been investigated in humid lowlands with high rainfall. There is a need to focus research on testing the practice under varied agro-ecological conditions, and using several suitable multipurpose trees species at a wide range of alley width and plant population. Investigations should include more than one crop in the alleys, and at different spatial arrangements. Management schedules, like time and frequency of pruning the trees and method of applying the prunings under different ecological conditions need more research attention. Studies on competition also need to be undertaken in order to suggest improvements to the practice.This paper attempts to put together and discuss some of the recent advances on these and other management aspects concerning hedgerow intercropping, and areas that need further research endeavour are exposed.  相似文献   

16.
An inventory of plant species was conducted on farms, farm boundaries and homesteads in the Kilimanjaro agroforestry system. The survey covered 30 farms in 6 villages in Hai District on the slopes of Mount Kilimanjaro, Tanzania. Over 100 plant species spread over 40 families were identified and their uses obtained through interviews with farmers. The species identified include 53 tree species, 29 food crop species, 21 non-woody plants of economic value and 8 weed species. The food crops, trees and other economically useful plants are carefully chosen by the local farmers and intimately intercropped on the same unit of land. In most cases, the plants had two or more uses of which food, fuelwood, medicine, poles, timber and fodder were the most important.  相似文献   

17.
Thailand aims to increase the use of renewable and alternative energy by 25% of total consumption under the Alternative Energy Development Plan (AEDP 2012–2021) by 2021, which include outputs from energy crops. This initiative is likely to put pressure on land resources, especially near parks and protected areas. Our study examined energy crop plantations, farmer responses to the AEDP, and community roles in forest protection in four villages adjacent to Phu Wiang National Park, Thailand in 2014. The majority of respondents (80%, n = 50) used their land for rice cultivation, but many villagers increased plantings of sugarcane (54%) and cassava (20%) because of high market demand for energy crops. Only a few examples of agricultural expansion into the national park were observed. Nevertheless, encroachment is likely to occur at this and other national parks as a result of government incentives to plant energy crops and the limited availability of agricultural land. Reliance on community-based management strategies may not be powerful enough for villagers to withstand the pressures of modernization, materialism, and other socioeconomic influences, possibly negating the effect of sustainability. Striking an equitable balance between government policies, community development, and forest protection will be a challenge for resource managers.  相似文献   

18.
This paper examines how agroforestry-based farming systems evolved in the Dhanusha district of Nepal following the conversion of forest into agriculture during the early 1950s. Some data are from two focus group discussions with agroforestry farmers and one meeting with agroforestry experts. The farmers?? discussion traced the development of farming practices from 1950 to 2010 to identify the drivers of land use change. The experts?? discussion resulted in a scale to differentiate the prevailing farming systems in the study area considering five key components of agroforestry: agricultural crops, livestock, forest tree crops, fruit tree crops and vegetable crops. Data related to the system components were collected from the randomly selected households. The study reveals that land use had generally changed from very simple agriculture to agroforestry, triggered by infrastructure development, technological innovations, institutional support (subsidies and buy-back guarantees) and extension programs. A range of farming systems with varying degrees of integration was evident in the study area: simple agriculture; less integrated agroforestry; semi-integrated agroforestry and highly integrated agroforestry. The three types of agroforestry systems, which are the focus of this study, varied significantly in terms of farm size, cropping intensity, use of farm inputs, tree species diversity, tree density, home to forest distance and agricultural labour force.  相似文献   

19.
Agroforestry is not likely to be accepted, particularly by small-holders, unless it is proved superior to other forms of land use not only on ecological but also on economic grounds. It is therefore argued that economic parameters concerning the quantitative productivity of all agroforestry systems components have to be a matter of concern to both research and development in agroforestry.In the process of screening selected relevant literature and as a result of a search of ICRAF's Multipurpose Tree and Shrub Data Case, the yawning gap between the high level of knowledge on agricultural crops on the one hand and the low level on woody perennials on the other is exposed as a serious obstacle to the analysis of agroforestry systems and to the further development of agroforestry. The lack of knowledge on woody perennials, as substantiated in this paper, concerns particularly quantitative production data on trees and shrubs used in agroforestry systems.It is also argued in support of the views cited from other authors that what little there is by way of yield data on woody perennials is scattered and distributed over a vast amount of literature, and thus often difficult to access and to retrieve, and often difficult if not impossible to compare owing to different methods and parameters employed in attaining the data.Although the difficulties of yield assessment are appreciated, increased efforts to obtain more — and more comparable — data on te productivity of woody perennials are advocated. In support of this call for stepping up appropriate activities some preliminary suggestions are presented on how to standardize parameter of yield assessments to achieve better comparability and how to increase accessibility of yield data and promote retrieval of data by the establishment of supplementary data bases.  相似文献   

20.
Mt. Kilimanjaro area with the old Chagga agroforestry system has been one of the most productive agricultural areas is Tanzania. Today the area is facing several challenges that affect people’s livelihoods. To study implications of low coffee price, population pressure and ensuing land use change on the farming systems and livelihoods of the people of the southern slopes of Mt. Kilimanjaro, Tanzania, an interview survey was conducted. A multivariate regression analysis was used in studying and testing the interrelationships between farm production and some socio-economic variables (assets). From nine different independent variables only land size and farmers age had statistically significant influence on revenue from the main crops grown. This suggests that families have so many different combinations of assets and farm-specific temporally varying strategies and objectives that it is not possible to find clear patterns of assets and strategies that would lead to successful livelihood outcomes. Due to sinking coffee prices in the world market, farmers have been looking for alternatives to earn cash. As land scarcity hinders both expansion of cultivation and expansion of animal keeping, more intensified and diversified production and off-farm activities have become crucial. There is an urgent need for technical research and experimentation on new agricultural options for the area and a need of understanding and creation of marketing channels.  相似文献   

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