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61.
P. J. Maille 《Agroforestry Systems》1991,14(2):145-148
When evaluating the economics of a joint production agroforestry system two rules should be followed: (1) all benefits and costs need to be included and (2) revenue streams over time should be compared using the net present value of an infinite set of rotations. To illustrate both points, previously presented data on the economics of eucalyptus plantings around agricultural fields are reevaluated below. 相似文献
62.
An analogue approach to analysing the traditional homegardens of Keralavis-à-vis natural climax ecosystems is adopted. The traditional homegarden is apparently a climax ecosystem, where ecological succession is consciously manipulated by human beings. High intensity of vertical and horizontal space use, the highly dynamic chronological structure and the capacity to perform essential ecological processes make this ecosystem relatively sustainable. Homegardens in Kerala effectively serve as human ecosystems with their low input demand, staggered supply of outputs, and enhancement of habitat quality. However, recent trends in agrarian structure and the high market orientation exert pressures on the homegarden, and its sustainability as a human ecosystem is in question.This joint paper is based on part of the research conducted by Darley Jose for the degree of M.Sc. (Natural Resource Management) at the Agricultural University of Norway under the guidance of N. Shanmugaratnam. 相似文献
63.
The Rwandan farmers, faced with a perpetual land shortage, have evolved certain intensive systems of organic agriculture. These systems, particularly the homestead (compound) farming, involve the combination of food, fodder and tree crops. to a certain extent these systems can satisfy the multiple needs of the subsistence farmers living under several risks and constraints. However, they cannot cope with the expanding food demand of the rapidly increasing population. Some multipurpose, low-input technologies and agroforestry approaches have been designed to improve the productivity of these traditional systems; these include inter/mixed cropping systems and rotations, alley cropping with leguminous trees and shrubs, use of planted fallow, planting tree legumes on anti-erosive lines, mixed farming,community forestry and woodlots, and tree planting on farm/field boundaries. The essential aspects of these technologies are briefly discussed.ISAR-IITA FSR PROJECT, B.P. 629, Kigali RwandaISAR-Swiss Intercooperation, c/o Forestry Department, B.P. 617, Butare, Rwanda 相似文献
64.
The focus of foreign direct investment (FDI) in the global forest sector has shifted from developed to developing economies (currently accounting 73% of total) during the past two decades. China has been the main global driver with its annual FDI soaring from USD 130 million in 2002 to USD 550 million in 2010. In light of international economic and business theories, choice of foreign entry mode is considered the most critical issue in corporate expansion strategy, which, however, has not been empirically studied in the forest sector. To fill this gap, our paper focuses on modeling two equity-based entry mode choices (i.e. wholly owned subsidiary or joint ventures) of foreign investment projects in China based on data from 109 activities of the Top 100 forest, paper, and packaging industry companies. By using logistic modeling, the main determinants of corporate entry mode choice are found to be cultural and geographical distance between the corporate home country and China, duration of corporate presence in China, and spatial concentration of local-level forest industry. Instead, investment project size and local resource availability are found to have no significant impact on corporate entry mode choice in China. 相似文献
65.
A mail-out survey questionnaire was developed by the Agroforestry group at the University of Guelph to determine the level of awareness and interest in the adoption of agroforestry systems by landusers from four townships in Wellington County, Ontario. The questionnaire investigated: (1) the current level of knowledge regarding windbreaks, woodlots and plantations, intereropping, riparian plantations and silvipasture, (2) the present level of participation in each of these systems on-farm, (3) the perceived benefits and/or drawbacks of each of these initiatives with respect to total farm income, income diversity, land rehabilitation, land value/equity, soil/water conservation, labour intensity, overhead and return on the term of investment.The majority of respondents were familiar with conventional agroforestry systems such as windbreaks and woodlots/plantations (80%, 62% respectively), therefore the level of interest in the adoption of these practices was significant (74%, 66% respectively). Response rates were lower for silvipasture, riparian plantations and intercropping, most likely as result of the low level of familiarity with these practices (20%, 32%, 4% respectively). Respondents commented that agroforestry systems would have a neutral effect on farm income, and would increase land stewardship. In some cases, interested landusers indicated a willingness to participate in agroforestry systems even though they anticipated increases in overhead and labour intensity; however, this was only true if they held land stewardship as a priority. Landusers were more concerned with the economic aspects of agroforestry, as a determinant to the future adoptability of particular practices. Age, gender, farm operation and farm size were not correlated with the adoption of agroforestry systems.The success of agroforestry programs on farms in the study area is largely dependent on the attitudes and willingness of landusers to participate in non-traditional agricultural systems. 相似文献
66.
John ?O.?BrowderEmail author Randolph ?H.?Wynne Marcos ?A.?Pedlowski 《Agroforestry Systems》2005,65(2):99-111
In July 1992 the Rondônia Agroforestry Pilot Project (RAPP) was launched in two agricultural municipalities (Nova União and Alto Paraiso) in the western Brazilian Amazon State of Rondônia. The purpose of the RAPP was to assess the conditions under which colonist farmers in the western Amazon would integrate agroforestry plantings into their small-scale farming systems and to assess the performance of those plantings over time. An experimental group consisting of 50 small-scale farmers was selected to participate. Plots were designed to accommodate between 3 and 25 different species, each producing one or more commodities with local market potential (hardwood, fruits, nuts, latexes, oils). Farmers planted seedlings typically on a 1-ha plot, located and designed by each farmer with the advice of a professional Brazilian extensionist. During the first phase of the project (1992–1998), the growth performance of the seedlings and changes in household characteristics were monitored on an annual basis. By 2002, 32 (64.0%) of the original 50 agroforest plots were found in place. This paper updates the research findings based on a 2002 follow-up visit to these 32 farms. In addition to growth performance, the authors’ found that 17.95% of the farms in the neighboring control group had planted trees and other agroforest crops between 1992 and 2002, compared to only 5.38% of farms outside the project area, suggesting spontaneous diffusion. The authors also found a potentially synergistic relationship between agroforestry and secondary forest regeneration with the use of satellite image analysis. The experience of the RAPP indicates that colonist farmers in Amazonia can be successful managers of agroforest plots with minimal external inputs over the long-term (10 years). 相似文献
67.
Legesse Negash 《Agroforestry Systems》2002,56(1):39-46
Erythrina brucei Schweinf. emend. Gillett (Papilionaceae),a tree species that is endemic to Ethiopia, is known to possess useful agroforestry attributes, but these attributes have not been quantified. To achieve this, propagation of the species, growth rate of young trees and their impact on barley (Hordeum vulgare L.), and leaf-nutrient concentrations were examined. Germination of seeds planted in plastic pots varied from 73 to 93%, and direct seeding in the field yielded 83%germination. Branch cuttings obtained from 2 to 3-year-old stock plants (n =150) resulted in 70 to 80% rooting within 8 to 12 weeks after setting cuttings into the rooting medium. Considerable nodulation occurred on leaves one year after planting out seedlings and stecklings. Leaf concentrations of Mg, N,P, and S were significantly lower in nodulated than in the non-nodulated leaves. On the other hand, leaf Fe concentration was higher in nodulated than in the non-nodulated leaves. There was no significant difference in Ca and K contentsbetween the nodulated and non-nodulated leaves. E. brucei-treatment significantly increased tiller and seed numbers, as well as seed weight. However, thousand-grain weight and grain size were similar in harvests from E. brucei-treated and the control plots. The results indicate that the species is easy to propagate by seed and vegetative means, grows fast, is desirable for intercropping, and has relatively high leaf-nutrient concentration.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
68.
69.
通过对山西省偏关县退耕还林、加快后续产业发展主要做法的调查。认为柠条先行、灌草结合、兴林促牧是一条改善生态、发展经济、农民增益、实现“三嬴”之路。推进灌草结合造林模式,不仅缓解了林牧矛盾,巩固了退耕还林成果,也为加快农村产业结构调整、推动农民在退耕还林后发展商品型畜牧业创造了有利条件。 相似文献
70.
由于港珠澳跨海大桥联通三个不同体制的区域,故大桥的合理收费管理模式对大桥的建设有较大影响。本文着重研究了拟建的港珠澳跨海大桥收费模式的基本特征,包括大桥的收费制式、收费方式和收费广场设置情况,为大桥建成后能够顺利运营收费提供了科学的方法。 相似文献