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1.
S. Fujisaka 《Agroforestry Systems》1991,13(2):95-109
About 25% of Laos' four million people practise shifting cultivation (mainly of rice) on a third of the country's cropped area. Official policy is to eliminate shifting cultivation by the year 2000. Diagnostic surveys of shifting cultivation were conducted in Luang Prabang and Oudomsay Provinces in northern Laos to understand the practice from a farmer's perspective, to observe fields, and to identify and give priority to problems and research to address problems. Weeds, low and possibly declining soil fertility, intensification of the cropping cycle, rats (plus birds, wild pigs), and insects lowered rice yields or reduced system sustainability. The forest ecosystem has been degraded by logging, burning, and rice monocropping; and potentials for environmental rehabilitation through natural succession are minimal. Farmers cannot adopt high labor and cash cost innovations; and improved fallow is needed as an intermediate step prior to crop diversification, adoption of agroforestry technologies, and sedentary agriculture. 相似文献
2.
混农林业历史发展概述 总被引：2，自引：1，他引：1
混农林业历经了游耕制和轮垦制，间作、套种制，混林农业和现代混农林业等发展阶段。混农林业的发展方向是经营模式多样化、系列化，经营技术集约化、科学化。 相似文献
3.
Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured quarterly survey in two villages. Qualitative and supplementary quantitative analysis methods were used to assess the financial potential of agroforestry systems. Various patterns of agroforestry exist in the study site, but all have two common principles, namely ‘integration with agriculture’ and ‘multi-functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry. 相似文献
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We tested the economic value of ecological knowledge in a midwestern USA alley-cropping system where row crops are planted in alleys between fine hardwood trees grown for veneer. Economic models were constructed to compare among agroforestry designs as well as to compare agroforestry with traditional forest plantation culture and row crop monoculture and rotational management. The general modeling approach was to quantify production inputs and outputs, estimate costs and revenues, simulate tree growth and crop productivity in agroforestry configurations, and estimate discounted cash flows. We incorporated scenarios that controlled both above- and below-ground competition through appropriate management as found in our previous research. This research showed the importance of below-ground competition in determining crop yields and the period of time that crop income could be expected from the agroforestry interplanting. Net present values and internal rates of return showed that agroforestry systems were generally more favorable investments than traditional agriculture and forestry. More importantly, the use of simple management techniques targeted at reducing below-ground competition allowed longer cultivation of row crops, greatly increasing returns to the landowner. Thus, the economic benefit of understanding the ecological interactions within agroforestry plantings dictates that accurate assessment of agroforestry alternatives will require the modeling of agroforestry as an integrated, interactive system.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
6.
Historical development of agroforestry in China 总被引：3，自引：0，他引：3
In China both agriculture and agroforestry originated in forests and developed side by side from their very beginnings. As revealed by archaeological evidence from ancient times, ancestral Chinese inhabited forests where they sheltered themselves from external hazards and lived on the edible parts of plants and animals through hunting and gathering activities.As early as the New Stone Age (7000–8000 years B.C.), fire was commonly used to burn the forests for slash-and-burn cultivation, which is a primitive form of agroforestry. Along with the rapid growth of population, the annexing of tribes, the collapse of clan society and the development of the slavery system, the nomadic mode of slash-and-burn farming evolved into settlement farming in the Xia Dynasty (2000-1600 B.C.). Peasants then engaged in settled cultivation.During the Shang and West Zhou Dynasty (1600-800 B.C.), perpetual settlement farming encouraged the development of private land-ownership. Peasants planted trees in or around the crop fields and grew fruit plants, vegetables and farmed domestic animals in their home yards for self-sufficiency. Since then, various forms of agroforestry have gradually developed and laid the fundamental framework of the Chinese small-farming economy for more than 3000 years.There has been a rapid growth of population in China over since the 1950s. At the same time, the area of arable land has decreased drastically and the environment has degraded rapidly as industrial development has taken place. The traditional labour-consuming and ineffective agroforestry management practices have not adapted to the current situation. In view of economic, ecological and social benefits, conversion of mono-biological production into a trinity system of agriculture, processing and marketing is suggested and planned experimentally. Such a management system, known as modern agroforestry, could be very beneficial to the development of modern China's rural economy and environmental conservation. 相似文献
7.
D. M. Kummer 《Agroforestry Systems》1992,18(1):31-46
Population pressure, expansion of small-scale agriculture and shifting cultivation are commonly cited as the causes of tropical deforestation. A close examination of deforestation and agriculture in the Philippine uplands reveals, however, that the vast majority of agriculturists must be sedentary farmers. In addition, the importance of population pressure as a cause of deforestation in the Philippines cannot be supported by the available evidence. Lastly, the concept of arable land is shown to be of limited value in discussing upland agriculture in the Philippines. 相似文献
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Farmers are often blamed for destroying the tropical forest, especially in Laos. Converting shifting cultivation into cash
crop based agriculture is frequently presented as the solution for merging forest protection and poverty alleviation, but
many attempts have ended in failure. A rural development project has attempted to introduce medicinal cardamom (Amomum villosum) cultivation in the notably remote region of Phongsaly (northern Laos), for export to China. With nearly 300 ha planted,
the crop now involves about 75% of the farmers in the region. Farmers fitted cardamom into their farming system, to suit their
needs for sustainability with a crop compatible with existing practices. Results indicate that introducing a cash crop into
a shifting cultivation region is possible if a greater attention is paid to: (i) appraise how the new crop fits into the farming
systems; (ii) prioritise economic issues over agronomic matters, in particular identify markets, traders or commercial risks. 相似文献
10.
As a system of land use which entails the deliberate association of trees with herbaceous field crops in time, shifting cultivation is one of the most ancient, widespread and, until recently, ecologically stable forms of agroforestry. However, under pressure of population and competing uses for land and labour, traditional swidden systems have been observed historically to undergo more or less predictable processes of intensification. Since shifting cultivation is an indigenous form of agroforestry, scientific agroforestry is not, strictly speaking, an alternative to shifting cultivation, but rather a systematic approach to the recombination of its basic elements into more intensive, sustainable and politically viable forms of land use, whenever pressures signal the need for change in traditional swidden systems.Different agroforestry options open up from different stages of intensification in swidden systems. A review of evolutionary typologies of shifting cultivation gives rise to a framework for the identification of agroforestry interventions and development pathways appropriate to specific systems. technological proposals are limited to a short list of the most promising agroforestry interventions in main sequence swidden systems. These include integral taungya, economically and biologically enriched fallows, variations on the alley cropping theme, and various tree crop alternatives to annual cropping systems. Examples and quantitative data are cited to substantiate the main hypotheses behind the proposals. 相似文献
11.
The problems of too much pressure on land for the production of food and wood for the increasing population have made it mandatory
to look into the various ways of maximising the uses of agricultural land in different parts of the world. Under this high
demand for land, the system of shifting cultivation which has been practised from time immemorial can no longer support the
needs of farmers in Nigeria. As a result of this, the different agroforestry practices have received increased attention.
The experiences obtained with shifting cultivation, homestead gardens, taungya, alley-farming and scattered farm tree methods
including shelterbelt planting in the country are reviewed in this paper and some research findings on these practices are
highlighted. 相似文献
12.
国名{造林树种}一’造林方式及生长量}备注日·…::‘“馨双__…一煲忿童筹;嘿哼6万株’当‘产量…力口重物髻翼子矗羹羹、‘材二….按树.….2。竺鬓:;:,收获后萌.芽更‘,年均生长‘…生一 …·…·短轮伐期:伐期l。·,株行足巨3·3。,预计·… 卜、…、卿咖,树高‘sm,年均生长歇。一30ms/ha。{ }}超短轮伐期:伐期l一3年,株行距。.3xo.gm,}用于造纸工业,也适用于 加拿大}白杨{{ }…干物质年均生长量为15t/hao{能源。 {{中短轮伐期’伐翔5一6年,“固氮植物混植,} {{收获后萌芽更新。}一…鬓:羹攫、!方翼二熏轰氨“;!Zt/ha。开展栽植密度、育… 相似文献
13.
K. F. Weersum 《Agroforestry Systems》1982,1(1):53-70
Agroforestry is a general concept for a land management system combining trees and agricultural crops. For application, various specific techniques can be chosen. Each of these techniques is adjusted to a specific set of environmental as well as socio-economic factors. Agroforestry cultivators or managers belonging to varying social strata and institutional groupings may practice different forms of agroforestry, even within the same general region. This is demonstrated on the basis of two contrasting types of agroforestry which are found on the Indonesian island of Java. Tree gardening or the cultivation of a wide variety of crops in a multiple-storeyed agroforestry system is an indegenous practice on private lands, while taungya or the intercropping of young tree plantations with staple crops is practiced on state forest lands. Both systems are described as to their management characteristics, past development as well as possibilities and constraints for further development. These two practices are then compared as to various attributes, like producer group, production purpose, area of cultivation, land ownership situation, structural organization of crop combinations, possibilities for improved cultivation techniques, and suitability for application in rural development for specific target groups.This paper is a slightly revised version of a contribution to a lecture series on agro-forestry organized by the Departments of Forestry, Wageningen University. 相似文献
14.
Shifting cultivation is a common agricultural practice that is the basis of subsistence for many rural populations throughout
the Tropics. The recent strong trend towards shorter fallow periods has led to widespread concern about declines in soil fertility,
crop yields, and food security. Unlike most research on this problem, we focus here on steeply sloped regions such as Mizoram
state in northeast India where most land is at an incline of >33°, and the potential for relatively large soil erosional losses
may necessitate distinctive solutions. Our goal is to review the relevant literature so as to optimize the direction and quality
of future science research on shifting cultivation in Mizoram. Our analysis suggests that the most promising options for improving
shifting cultivation are nutrient and water supplementation, optimising crop choice, extending the site use period, enhancing
the fallow recovery rate, and controlling the burns and their environmental impacts. Promising alternatives for replacing
shifting cultivation include inter-row cropping between contour hedgerows of nitrogen-fixing shrubs, slope terracing, agroforestry
with anti-erosional plants, and bamboo forest harvesting. In addition, we identify the principal research questions that should
be addressed before each of these options can be evaluated and recommended as part of land use planning initiatives. Overall,
we conclude that intelligent and careful use of commercial fertilizer in combination with organic matter additions is likely
to be an important feature of many of the solutions to the problem of shortening fallow periods in shifting cultivation on
steep slopes. 相似文献
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The farming system and traditional agroforestry systems in the Maya community of San Jose, Belize 总被引：3，自引：0，他引：3
Shifting slash-and-burn agriculture is likely one of the main causes of forest degradation in southern Belize. Although many development projects have attempted to reduce the impacts of agriculture on the tropical rainforest, the situation is still a cause for concern. A study of the farming system of the San Jose Maya community was therefore carried out to examine agricultural production in its social, cultural, economic, and political context. Results demonstrate that agricultural production contributes to forest degradation because of the limited availability of agricultural land, the low level of investment in agricultural production, the land tenure system, limited marketing opportunities, and the exclusion of Mayas from the country's political and economic domains. Agroforestry could, however, offer a partial solution to the problem of forest degradation. Three types of traditional agroforestry systems are practised in San Jose: the milpa (a slash-and-burn agriculture system), cacao (Theobroma cacao) cultivation under shade trees, and the homegarden. These traditional agroforestry systems almost entirely meet a family's needs for food and wood, and generate at least 62% of family income. Improving the productivity of these systems could help to reduce pressure on the forest in southern Belize.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
17.
H. J. Von Maydell 《Agroforestry Systems》1990,12(1):91-96
Integrated land uses, many now referred to as agroforestry, have a long history in Europe. In the past, the main trend was
the movement of agricultural and pastoral activities into forests. The introduction of trees into non-forested (or once forested)
lands is a much more recent occurrence, particularly the cultivation of high value fruit and nut trees in the Mediterranean
countries, hedgerows/windbreaks in northwestern Europe and windbreaks in eastern Europe and the southern Soviet Union. Environmental
concerns of intensive agriculture are increasing the demand for alternate production systems such as agroforestry. Education
and training in agroforestry in Europe is very diverse because of the country specific issues regarding land use. 相似文献
18.
Causes and consequences of shifting cultivation and its alternative in the hill tracts of eastern Bangladesh 总被引：1，自引：0，他引：1
Shifting cultivation, which is still prevalent in the uplands of eastern Bangladesh, contributes significantly to forest loss
and is the main cause of land degradation. This paper presents the causes and consequences of shifting cultivation and its
potential land use alternatives. The analysis presented is primarily qualitative with a supplementary quantitative analysis
of the causes of forest loss by logistic regression. The results of the study show that traditional land practices, exacerbated
by poverty and associated with a lack of technical knowledge is the main cause for the continuation of unsustainable shifting
cultivation. Population pressure, inadequate land for cultivation, low education levels, policy planning and implementation
without local participation are all factors that influence farmers’ decision to continue shifting cultivation. Intensive land
management through agroforestry is a promising alternative that can sustainably manage the remaining forest resources. If
adopted, such systems potentially provide good economic returns, and may significantly reduce rural poverty. 相似文献
19.
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
20.
Historical development of a permanent agriculture system based on the use of agroforestry in the temperate zone is traced. In general, reasons for a renewed interest in agroforestry include the end of cheap, subsidized fossil fuels; increased concern about soil erosion and marginal land use; an international awakening as to the dangers of indiscriminate use of pesticides, herbicides and other chemicals; and a need to balance food production with other land uses.For the forestry profession in particular, reasons for interest in agroforestry stem from a need to revitalize rural economies, the desire to increase timber exports, and potential resolution to land use conflicts between agriculture and forestry. Through use of agroforestry management systems, an increase in both economic and silvicultural benefits are obtainable.Two agroforestry management systems are reviewed which currently appear feasible for implementation in many industrialized countries of the temperate zone. These two systems include: 1) Animal grazing and intercropping under managed coniferous forests or plantations; and 2) Multicropping of agricultural crops under intensively managed, high value hardwood plantations.Michigan Agricultural Experiment Station Paper No. 12046. 相似文献