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1.
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   

2.
Review on Agroforestry Systems in China   总被引:3,自引:0,他引:3  
INTRODUCTIONChina is the most populated country in the world. Thepopulation of the mainland amounts to 1.3 billion in2004. The land area is approximately 9.6 million km2,of which the proportion of arable land is low. Thiscovers about 10% of the total land area; on the average,there is around 0.09 ha of tilled land per capita.Furthermore, the arable land is unevenly distributed inthe country. Forests cover 13.92% of the whole landarea, 134 million ha or 0.095 ha per capita (Xu Xingquanet …  相似文献   

3.
Agroforestry是国际国内的热门课题。中国是国际公认的Agroforestry的大国,但国内中译名十分混乱,有译成农林业、混农林业,农区林业、农林复合经营体系等。讨论并统一Agroforestry的中译名,不仅是一个学术名词问题,而且还关系到学术概念与学习内涵的统一,也关系到农、林混作地区林业事业的长期稳定和林业生产的持续发展。国际农林业研究会(ICRAF)对Agroforestry作了这样的定义:“Agroforestry是一种土地利用技术和系统制度的复合体系,是有目的地把多年生木本植物与农业、牧业用于同一土地经营单位,并采取时空排列或短期相同的经营方式,在复合系统的不同组成之间存在着生态学和经济学方面的相互作用。”这个权威定义,主要是两方面的内容:(1)这是一种有目的地使农业与林业、牧业在同一块土地经营的种植制度,(2)在这种种植制度的不同组成之间存在着生态学与经济学方面的关系。 1989年秋季,在林业部委托中国林科院举办的黄淮海开发林业技术研讨会上,一些专家提出了这个问题,并主张把Agroforestry中译名译成“农用林业”,与此同时中国林科院林研所的学术刊物《泡桐》已更名为《泡桐与农用林》。对此,我们提出不同看法,与同行专家商榷。我们认为这个译名是不妥的,主要理由是:  相似文献   

4.
In this study we analysed: (1) the biodiversity conservation capacity of Agroforestry Systems (AFS) in temperate highlands of the Tehuacán–Cuicatlán Valley, Central Mexico, (2) human cultural motives and actions for conserving such diversity and (3) problems endangering that capacity. We evaluated the richness and diversity of perennial plant species maintained in AFS through vegetation sampling of 14 agricultural plots and compared their composition with that of natural forests (14 plots of 500 m2 each). We examined the situations among communities of Náhuatl, Ixcatec and Cuicatec people, documenting through interviews the management practices of plant species and the whole system, reasons why people maintain vegetation cover within AFS, and factors influencing changes in decisions favouring agriculture intensification. In the AFS studied we recorded a total of 79 species of trees and shrubs, 86 % of them being native species and representing 43 % of all species of trees and shrubs recorded in the sampling of the natural forests the AFS derive from. People leave standing on average a total of 40 individual trees and shrubs per agricultural plot. Reasons for leave plant species standing were more frequently associated with their use as fruit trees, firewood, shade, beauty, respect to nature and other environmental benefits. Water availability for irrigation, land tenure, and dependence on agriculture and forest for peasant's subsistence were main decision factors influencing AFS variation in their composition. AFS in temperate zones are important reservoirs of biodiversity and biocultural heritage and should be keystones for conservation policies in the Tehuacán–Cuicatlán Valley.  相似文献   

5.
The influence of farmers’ mental models on the success of an agroforestry extension program on Leyte Island in the Philippines was investigated. Knowledge of farmers’ mental models and hence the likely acceptance of technology was used to inform the design of a hypothetically expanded program. To gain an insight into the reasons behind differing acceptance of extension assistance, data were collected and analysed from formal interviews, translated conversations and visual observations. The data provided a chain of evidence and triangulation between farmers’ stated intentions and their actions. Farmers had little prior knowledge of nursery technology and were highly receptive to extension assistance which enabled them to develop high self-efficacy in seedling production. However, farmers’ rejection of silvicultural advice to thin and prune existing plantations was predicated by existing attitudes to forest resource management. Farmers also expressed a strong preference for a low-cost and low-input approach to establishing timber trees. Visual observations of farmers’ tree establishment practices indicated the existence of gaps in their knowledge of tree growth processes. This investigation illustrates the need to elicit farmers’ mental models as a parallel enquiry to extension activities. If agroforestry extension is to be constructivist and participatory, accommodation of farmers’ mental models and modification of program goals may be necessary. Relatively little is known about the reasons for farmers’ acceptance or rejection of silviculture in Leyte and these results indicate that further research into the way that farmers’ mental models filter and guide acceptance of advice may be worthwhile.  相似文献   

6.
A mid altitude (700–1200 m amsl.) village in Garhwal Himalaya was analysed in terms of energy and economic efficiency of different land use-land cover types constituting the landscape. Simultaneous agroforestry, sequential agroforestry, home garden and community forests accounted for 27.47%, 27.47%, 1.1% and 43.96% of the total geographical area of the village. Simultaneous agroforestry is the traditional land use involving substantial input of manure derived from forest litter and animal excreta and was practised on terraced slopes in private ownership. Tree cover in this system was represented by nine species with total average density of 390 trees ha−1, Grewia optiva and Boehmeria rugulosa being the most dominant. Sequential agroforestry system involving slash-burn practice and cultivation on unterraced slopes without tillage and manuring was an illicit land use on community lands where forestry land use is desirable as per the government policy. Per ha annual energy input in simultaneous agroforestry system was 305267 MJ compared to 279 MJ in sequential agroforestry and 27047 MJ in home garden. In monetary terms, highest per ha annual output was obtained from simultaneous agroforestry (Rs 25370, Rs 35 = US$1) followed by home garden (Rs 18200) and sequential agroforestry (Rs 9426). Local food, fodder and fuelwood production was in excess of the local consumption. While most of the surplus food was stored, surplus fodder and fuelwood were sold for cash. Production in simultaneous agroforestry system in private lands was sustained with substantial biomass and nutrient inputs from the community and government forests. Land use-land cover changes in the region are driven by the interaction of ecological, policy and human factors. It is concluded that present policy of treating forests and agriculture as closed and independent ecological or production systems needs to be replaced by an integrated land use policy. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

7.
SeniorAgroforestrySpecialistsForumHeldinBeijing¥//AforumforsenioragroforestryspecialistswasheldinBeijingfromMarch29-31,1994.T...  相似文献   

8.
Fuelwood is the main source of energy for various household uses in many developing countries; and management of tree resources where it is obtained can be best undertaken when household choice patterns are understood. In this paper, households’ decision to obtain fuelwood for domestic consumption as influenced by household and fuelwood source characteristics is analyzed using a multinomial probit regression model. Data is obtained from 254 randomly selected household drawn from Mbarali district, south-western Tanzania. Results indicate that households are heavily dependent on natural forests for household energy provision and that the choice to obtain fuelwood from the forest, farm or market depends, among other factors on the availability of preferred fuelwood tree species at these sources. Acacia tortilis, Brachystegia spp. and Faidherbia albida are the significantly preferred tree species and hence affect the decision of where to obtain fuelwood. This revelation highlights the pressure applied to surrounding forests as well as to the aforementioned tree species which require immediate management interventions. The gender of the household head and whether the household lives in peri-urban or rural areas also influence choice of fuelwood source. Promotion of tree planting and on-farm management of tree species similar to preferred species found in natural forests is recommended. To the extent that consumer preferences are likely to change over time, further research using panel datasets is necessary to unravel inter-temporal preferences for fuelwood sources.  相似文献   

9.
The role of agroforestry systems in biodiversity conservation was investigated in the semiarid Tehuacán Valley, Central México. Richness and diversity of native plant species were compared between agroforestry systems (6 sampling sites) and the following forests (6 sampling sites) dominated by columnar cacti: (i) “chichipera” dominated by Polaskia chichipe; (ii) “jiotillal” dominated by Escontria chiotilla; and (iii) “garambullal” dominated by Myrtillocactus schenckii. Our information on genetic variation of dominant arboreal species in the study sites was reviewed and included in the analysis. Factors influencing household’s decisions to maintain vegetation cover were compiled through a survey and interviews and analyzed. All the samples of the agroforestry systems studied maintained on average nearly 59% plant species and 94% genetic variation of dominant cacti occurring in the forests, although their ability to preserve endemic rare species is limited. Social factors favoring maintenance of perennial species in agricultural plots include collective rules, households traditions, use of the plants maintained in the systems, and the environmental information gathered from NGOs, the local Biosphere Reserve, and researchers. However, agroforestry systems are losing their capability to maintain vegetation cover, mainly because of (i) decreasing amount of land managed by households, determined by a progressive fragmentation of the land area given to new families, (ii) adoption of technologies to intensify agriculture, and (iii) governmental programs penalizing the presence of vegetation patches within agricultural lands since they are considered “useless” areas. Necessary policies to stop degradation of the agroforestry systems and to improve their conservation capacity are discussed.  相似文献   

10.
StudyTouronCommunityForestryandAgroforestryApproachesinChina(Sept.16-29,1996)Thestudytourwillprovide4differentmodelsofsocial/...  相似文献   

11.
The status of agricultural non-point source (NPS) pollution in China is quite austere owing to lots of factors, the characteristics of which include severe N, P eutrophications in water bodies, unsuitable structure of agriculture and the lack of reasonable management. It was well known that forest could play an important role to control soil & water erosion, uptake extra soil nutrients as well. However forest coverage is rather low in the headwaters region. The research on the causes of NSP pollution and the significance by developing agroforestry to deal with the problem is presented in the paper, as well as the function of agroforestry and the related measures of pollution controlling, e.g., riparian forest buffer zones building. As a conclusion, controlling the loss of soil and water is regarded as an important crucial action and major research direction in the field. Thereby the benefits of pushing up agroforestry in slops to combat water eutrophication and prevent NSP pollution from worsening are significant.  相似文献   

12.
INTRODUCTION Schistosomiasis, snail fever, is a sort of parasite disease chronically, wildly and seriously injuring human health, especially in developing countries. WHO statistics indicated that about 200 million people in 74 countries, accounting for one third to a half of the population in disease prevailing area, has been suffering from epidemic snail fever. China is one of the countries suffering from snail-fever most in the world, about 100 million people at the risk of suffering fr…  相似文献   

13.
The Australian Master TreeGrower (MTG) program was launched in 1996 as an agroforestry extension initiative of The University of Melbourne. The program included a short course for landholders that provided knowledge and practical skills but also had a strong focus on developing the information and peer networks that would provide them, and their community, with on-going support as they implement their agroforestry activities. Since 2010 the MTG has been delivered by The Australian Agroforestry Foundation, a not-for-profit organisation, and integrated with the Peer Group Mentoring (PGM) concept developed by a regional farmer group in Australia. The PGM trains, then pays, past Master TreeGrowers to support other landholders as they design and develop their own agroforestry projects. More than 100 MTG courses have been run across Australia involving over 2000 landholders and more than fifty partner organisations. Independent evaluation shows that participants enthusiastically support the program, increase the area of tree cover on their land, adopt more intensive or purposeful management practices, are more inclined to want to grow trees for a mix of both public and private good outcomes, and, actively encourage others in their community to do the same. This paper reviews the development and delivery of the MTG and PGM in Australia and explores whether the models are transferable to developing countries. To date four MTG courses have been conducted in Africa (Uganda (2) and Niger (2)), seven in Indonesia and one in Timor-Leste. Whilst the structure of the international MTG courses was different to that commonly adopted in Australia the content was similar in that they included: information to support the development and implementation of agroforestry designs that reflect their particular interests and aspirations; a review of market opportunities for agroforestry products and services, training in tree and forest measurement, education in tree growth and silviculture; and, encouragement, guidance and support to encourage landholders to share their experience with others in their community. The response suggests that the MTG, originally developed for Australian farmers, may represent a very different model of agroforestry extension to what is commonly offered to farmers in developing countries, and that it may be worth developing in regions where farmers believe they have relatively secure land tenure and are able to make long-term land management decisions regarding tree establishment and management.  相似文献   

14.
Perceptions of the benefits of agroforestry practices (AFPs) and the level of utilization of these practices by male and female participants were examined in the agroforestry programs of the Akwa Ibom and Cross River State Governments of the South–South region of Nigeria. Responses were derived from 250 randomly selected respondents. Overall, respondents perceived the major benefit of agroforestry practices as enhancement of environmental conservation. Female respondents however perceived increased income as the major benefit of agroforestry practices. A composite perception index revealed that women farmers were more favourably disposed than male respondents to the utilization of agroforestry practices. The farmers were favourably disposed to the utilization of only five of the 16 identified AFPs in the study area, including ‘leaving of isolated woody trees on farmlands’, ‘utilizing woody trees as windbreaks’ and to ‘demarcate farm boundaries’, ‘planting of woody trees in combination with fruit trees’, and ‘planting of woody trees in combination with vegetable crops’. Male and female responses were generally similar although a major difference was observed with regard to ‘planting of trees for fuel wood’. The composite index, however, revealed a general low level of utilization of AFPs, although female farmers were relatively more disposed to the utilization of AFPs. The key policy implication of the study is the necessity to embark on sustained education and environmental awareness campaign, with a focus on presenting AFPs as livelihood sustaining and risk mitigation activities, against its present misperception as simply a government strategy to increase the stock of woody trees in the environment. This policy should endeavour to target landless women farmers who have been found to be more interested in the adoption of AFPs into their farming system.  相似文献   

15.
The need to carry out biological conservation outside protected areas requires avoiding, minimizing or mitigating impacts brought about by habitat transformation upon the biota. Usually, forest plantations hold fewer species than the original forest. However, structurally complex plantations support more species and individuals than simpler ones. Here we test if this phenomenon occurs in amphibian and reptilian assemblages, analyzing information regarding their richness and abundance in forestry plantations from 14 countries and 72 case studies which compare species richness and abundance in plantations and forests. Among amphibians, species richness is lower in plantations than in forests while among reptiles there is no significant difference. The abundance of reptiles increases in plantations. Three studies dealt with reptile assemblages in relation to structural complexity of plantation, which suggest that species richness and abundance is higher in complex plantations. Despite accounting for 50 % of the terrestrial vertebrates, herpetological studies account for 15 % of the research available regarding the impact of plantation upon vertebrates, information deficiency that hampers decision-making on the conservation of herpetozoans outside protected areas.  相似文献   

16.
Although agriculture generates 16% of Australia’s greenhouse gas emissions, it also has the potential to sequester large quantities of emissions through land use management options such as agroforestry. Whilst there is an extensive amount of agroforestry literature, little has been written on the economic consequences of adopting silvopastoral systems in northern Australia. This paper reports the financial viability of adopting complementary agroforestry systems in the low rainfall region of northern Australia. The analysis incorporates the dynamic tradeoffs between tree and pasture growth, likely forest product yields, carbon sequestration and livestock methane emissions in a bioeconomic model. The results suggest there are financial benefits for landholders who integrate complementary agroforestry activities into existing grazing operations at even modest carbon prices.  相似文献   

17.
Reducing carbon emissions from deforestation and forest degradation (REDD+) has become central to efforts to mitigate climate change. Approximately 10 % of the world’s forests are managed by local and indigenous peoples. Agroforestry may provide these communities with a means to engage in carbon offsetting initiatives without forfeiting access to, or benefits from, forests. Here, we present an analysis of social and ecological data from a four-year-old, reforestation-based carbon-offset project on the collective lands of Ipetí-Emberá, Panama. Mixed-species agroforests or timber-only plots were established by a subset of community members under voluntary carbon-offset agreements with a private client. We (1) describe how plot carbon accumulation trajectories were related to species composition; (2) determine if established agroforests are likely to meet carbon sequestration targets by the end of the 25-year project period; (3) describe the motivations and experiences of participants who chose to establish agroforests; and (4) compare socio-economics of participants versus non-participants. Our study provides data on early mortality, tree growth and the carbon sequestration capacity of 29 species that are commonly used by small farming households in Latin America and elsewhere. The study highlights strategies for reducing risks associated with agroforestry as a carbon sequestration strategy in the context of carbon offset projects, such as the replanting of dead trees and the establishment of a carbon buffer. We also provide evidence to counter claims that offset projects could amplify inequality in rural communities as participants to agroforestry, when compared to non-participants, were not remarkable in terms of their assets or wealth. Overall, this case study provides an encouraging example of how agroforestry may help forest communities engage with REDD+ in a way that benefits both their livelihoods and the global climate change agenda.  相似文献   

18.
Small-scale Forestry - Despite claims that plantations both enhance and undermine the quality, valuation and protection of natural forests, plantation forestry continues to expand worldwide. In...  相似文献   

19.
Whatare"river-connectedlakes" River-connectedlakesmeanthelakesthatareconnectedwithriversandintoorfromwhichthereisriverwaterorlakewaterfreelyflowing.Mostofthemedium-sizedorlargerlakes(morethan10km2)atthetwosidesoftheChangjiangRiverwereoriginallyriv…  相似文献   

20.
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