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1.
为了解我国桉树相关行业的发展动态,本文以中国知网数据库(www.cnki.net)的文献为数据源,以文献计量学方法,对我国1987—2016年共30 a的桉树专题相关文献进行阶段性(以10 a为界)统计,从文献数量、学科分布、研究层次、文献作者、发文机构、资助基金、文献来源和关键词等8个方面进行了分析.结果表明:随着年份增长,桉树专题文献数量总体呈现上升趋势,1987—1996、1997—2006及2007—2016年的文献数量分别为965、2115及4631篇,以第3阶段(2007—2016年)增幅最大.30 a间3个阶段桉树研究的学科领域均以林业学科最多,所占比例为70%左右,研究层次均以工程技术(自科)和基础与应用基础研究(自科)为主.不同阶段文献作者的最高发文数量分别为11、30和75篇,发文机构均主要集中在广东、广西、云南、湖南、福建等地.3个阶段的文献主要以国家科技攻关计划和国家自然科学基金资助为主,文献来源主要出自期刊,整个30 a间,均以《桉树科技》所刊登的文章数量为最多,是其他期刊的2~6倍.关键词均以"桉树"出现的频次最高,其他主要关键词主要为品种与人工林.  相似文献   

2.
Agroforestry research in academia and government and non-governmental agencies began by focusing on biophysical aspects. As this science represents a series of practices implemented by individual farmers, it requires in-depth social and economic analyses to assess economic feasibility of agroforestry systems, factors influencing the adoption of agroforestry, monitor the relevance and effectiveness of investigations, and guide future research efforts. This study presents literature dealing with socioeconomic issues in agroforestry research from interdisciplinary peer-reviewed journals, book chapters, and gray literature from 1992 to 2002. Over 500 publications were analyzed to determine relative dominance of geographical regions, types of analyses, agroforestry technologies, and socioeconomic issues. Trends were examined over time and by region. Overall, the body of literature exhibits an increasing trend toward regional and analytical diversity over time. Some deficiencies of regional and thematic nature were observed, which included underrepresented temperate regions and technologies such as riparian buffers, as well as only a small number of papers dealing with gender and property rights. These suggest opportunities for future investigations.  相似文献   

3.
Agroforestry Systems - While many agroforestry research projects contribute to improving food security, livelihoods and management of natural resources, few have had a significant role in achieving...  相似文献   

4.
Agroforestry Systems Inventory   总被引:2,自引:0,他引:2  
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5.
Agroforestry Systems - Increasing tree cover and managing trees better on farms in Ethiopia supports livelihoods and the environment but most tree-planting schemes promote only a few species. This...  相似文献   

6.
农用林业及其与社会林业的关系   总被引:1,自引:0,他引:1  
本文论述了在用林业的概念及分类,以及农用林业与社会林业的关系,农用林业是一独立学科,没有社会林业的介入,农用林业照样生存。农用林业是社会林业的基础,社会林业又是农用林业及其用户—农民的中间桥梁。  相似文献   

7.
India's long tradition of agroforestry has been influenced by numerous religious, social, and economic factors. Several indigenous agroforestry systems, based on peoples' needs and site-specific characteristics, have developed over the years. Agroforestry research was initiated in the country about two decades ago; since then, considerable progress has been achieved. The interactions between and among the tree, crop, grass, and animal components have been studied, and several agroforestry technologies have been developed and tried on farmers' lands. Agroforestry research is now conducted under the auspices of the All India Coordinated Agroforestry Research Project of the Indian Council of Agricultural Research at 31 centers distributed over India's tropical and temperate regions. In addition to research, the program includes agroforestry training of farmers, technicians, and scientists at 28 centers throughout the country. Expectations from agroforestry are high in India in both rural and urban areas; these expectations include production benefits that are in harmony with the ecology, environment, traditions, and heritage of the country.  相似文献   

8.
Agroforestry is one of the most sustainable land management systems practiced around the world due to the socioeconomic benefits that it brings to farmers. In Bangladesh, farmers practice agroforestry, applying indigenous knowledge. The present study was designed to identify the present status, management practices and its role in improving the livelihoods of farmers in northern Bangladesh. Data for the study were collected through quantitative and qualitative methods. A total of 29 tree and 38 agricultural crop species were planted by the102 farmers interviewed. Mangifera indica (relative prevalence 49%) is the most predominant species, followed by Eucalyptus camaldulensis (relative prevalence 35.4%). Farmers of northern Bangladesh plant trees in cropland for fruits (90%), fuel wood (87%) and timber production (79%). Fruit trees were planted with wider spacing while forest and fuel wood species were planted with narrower spacing. Farmer’s livelihoods improved enormously by practicing agroforestry as they have more access to food, fodder and fuel wood which is reflected by greater access to livelihood capitals (except social capital). However, farmers have experienced increased incidences of pests and diseases to the annual crops and trees. Agroforestry practices increases species diversity, ensure economic return and sustain farmer’s livelihoods.  相似文献   

9.
10.
The link between forest revenue administration and under performance of revenues from legal timber has received little attention in the literature. This article analyzes revenues from the timber royalty and reforestation fund fee, two important forest non-tax revenues in Indonesia whose tropical forest has been under threat of extensive deforestation particularly from commercial timber logging. It shows that revenue realization does not reflect potential with two key findings: first, timber royalty revenues represent only 52% of their potential, and second, revenues from reforestation fund fee suggest a counter-intuitive pattern – revenue realization is 34% above its potential. We provide plausible explanations from the perspective related to features of revenue collection. We further consider policy relevance in terms of forest revenue administration.  相似文献   

11.
Climate change is affecting the world’s ecosystems and threatening the economic system, livelihoods and availability of natural resources. Forest ecosystems can be carbon sources or sinks and are therefore integrated in international climate policy. Forest-related carbon mitigation projects are threatened by climate change through altered environmental conditions and forest processes, as well as through synergistic effects of climate change impacts with already existing socioeconomic and environmental stressors. Data on risk management and adaptation strategies were collected by a survey of 28 current forest projects targeting climate change mitigation. Ten of these represent the officially implemented afforestation (A) and reforestation (R) activities under the UNFCCC and the Kyoto protocol. Additionally, the official methodologies for AR activities under the CDM (Scope 14) were examined for potential climate change adaptation requirements. As a result, the adaptation of forest mitigation projects to climate change is found to be insufficient. A systematic approach for the inclusion of climate change risk management and adaptation is developed and guidelines for the design of “climate-change-proof” afforestation, reforestation and deforestation avoidance projects are proposed. A broader mainstreaming of the issue is required and clear policy regulations are necessary, especially for the post-Kyoto process.  相似文献   

12.
Forest regrowth is a notable phenomenon across the tropical forest latitudes. Such reforestation takes place in the wake of land abandonment, occurs cyclically in a rotational agricultural system, and may result from the deliberate planting of trees by farmers. Although less extensive than successional forest regeneration, tree planting by small farmers can have potentially important environmental impacts at both the site and global scale. This paper examines tree-planting efforts by small farmers in the tropical frontier regions of Panama and Brazil in order to gauge the magnitude of reforestation activities, and to identify factors that influence these efforts. This paper discusses the environmental regulations, forestry law, and tenure institutions in both countries, and performs a comparative analysis of reforestation efforts with information derived from household surveys (n = 356) and in-depth tree planting interviews (n = 35). Results from logistic regression are also presented. Our results show that tree planting occurs more frequently in Panama, which we attribute to greater external support in the provisioning of extension and materials and strong market incentives. We suggest that the proximity of the study sites to Panama City facilitates external support and market drivers. Finally, our results suggest that land tenure security is an influential determinant of reforestation activities in both countries.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

13.
14.
The state of the art of agroforestry diagnosis and design   总被引:2,自引:3,他引:2  
Seven years ago the International Council for Research in Agroforestry set out to develop a methodology for the diagnosis of land management problems and design of agroforestry systems. Since then over 60 documents (articles, conference papers and manuals) relating to the D & D methodology have been published by ICRAF and the methodology has been used to develop agroforestry plans and identify research priorities for a wide range of ecological and cultural conditions throughout the tropical regions of Africa, Latin America and Asia. This article reviews the evolution of the D & D methodology and suggests directions for its future development.Ecological Anthropologist, ICRAF  相似文献   

15.
Reforestation of degraded land in tropical regions provides one means of restoring ecosystems and improving rural livelihoods. Most plantations in humid tropical regions are established in pure plots, including few species of high commercial value, generally exotics. The present study compares growth and economic viability of 15–16 year-old trees of native species in pure and mixed plantations on degraded pasturelands at La Selva Biological Station, Costa Rica. The species with the best growth were Vochysia guatemalensis, Virola koschnyi, Jacaranda copaia, Terminalia amazonia, and Hieronyma alchorneoides. The mixed plantations performed better than pure plantations for all growth variables considered, including height, diameter at breast height, volume, and aboveground biomass. Mixed plantations outperformed pure plantations economically, with Net Present Value (NPV) of 1,124 to1,124 to 8,155/ha and Internal Rate of Return (IRR) of 7.7–15.6% depending on the species mixture. The most profitable pure plantations were those of Vochysia guatemalensis, with NPV and IRR of $6,035/ha and 14.3%, respectively; Hieronyma alchorneoides ($6,035/ha and 14.3%, respectively; Hieronyma alchorneoides (2,654 and 10.8%); and Virola koschnyi ($1,906/ha and 9.22%). These are the estimated benefits that would be accrued at harvest. These projections are realistic since the decision to harvest is generally mandated not just by profit maximization but by economic necessity, thus many small- to medium-scale farmers in Costa Rica harvest plantations prior to the completion of the rotation length. Mixed plantation may be the preferred system for reforestation with native species designed for timber production or carbon sequestration because this system is more economically viable and productive than pure plantations.  相似文献   

16.
Agroforestry options as a means of promoting reforestation were testedby establishing with 10 farmers simple comparisons between pure plantations andtimber trees with annual or perennial intercrops. Two year-old intercroppedtrees on-farm had 22–48% greater height and 24–38% greater diameterthan trees in pure plantations. The exception was Cordiaalliodora that did not respond significantly to intercropping withcassava (Manihot esculenta). Only intercrops with the mostvaluable crops on agricultural soils produced a return to labour above thedailywage rate. On non-agricultural soils, farmers only intercrop a small area oftheir plantations with subsistence crops to meet home consumption needs. In thecontext of Costa Rica intercropping appeared to have a limited potential tofinance the reforestation costs of farmers.  相似文献   

17.
Agroforestry has been considered a viable land-use system particularly in the tropical regions. In developing or designing agroforestry systems, various concerns have to be addressed namely: (1) economic; (2) biological and physical; and (3) silvicultural and ecological considerations. This paper addresses these concerns from an interdisciplinary perspective. A land-use allocation model which ensures the simultaneous consideration of these concerns is proposed.  相似文献   

18.
Disturbances that create gaps can shape the structure and function of forests. However, such disturbance regimes in Asian tropical montane rainforests remain largely unquantified. Least studied are typhoon disturbances that are attributable to climate change. We investigated gap characteristics in terms of size, age, and gapmaker to quantify the gap disturbance regimes in an intact old-growth tropical montane rainforest on Hainan Island,China. The intensity of typhoons has increased since 1949,and typhoon winds blow mostly(45.5%) from the northeast corner of Hainan Island, resulting in a higher frequency of gaps in the northeast. A total of 221 gap-makers(trees that fell to create canopy gaps) and 53 gaps were observed in a 3.16 ha old-growth rainforest. Most canopy gaps(85%)were 200 m~2. The average size of canopy gaps was smaller in the rainforest than in other tropical forests, while the average size of expanded gaps was similar to those in other tropical forests. The maximum age of gaps was 23.5 years indicating that gaps had more rapid turnover than other parts of tropical forests. The frequency distribution of gap-makers followed a lognormal distribution with a distinctive peak at three gap-makers, which was different from the inverse J-shaped curve typical of other tropical forests. Gaps were recorded mainly on slopes between 20° and 35° and wood density of gap-makers was between 0.6 and 0.7 g cm~(-3). Our results suggest that small-scale disturbance was the dominant agent of gap formation in this old-growth rainforest that is subject to increasing typhoon disturbances.  相似文献   

19.
Agroforestry is a key land use in the development of ecological corridors in tropical rainforests biomes. This research tested the social dimensions of agroforestry adoption and maintenance in the Atlantic rainforest of Southern Bahia, Brazil. A quasi-experiment research design compared a group of farmers who participated in an agroforestry development program with a group of similar farmers who were not participants in the program. The effects of the program on the participants’ self-efficacy, attitudes and intentions to adopt or maintain agroforestry were tested. The effects of socio-economic factors and attitudes were also compared to self-efficacy in terms of farmers’ intentions to adopt or maintain agroforestry. Results indicate that the program neither raised nor lowered the farmers’ attitudes, self-efficacy or intentions to adopt or maintain agroforestry. However, multiple regression and logistic model analyses indicate that perceived behavioral control, attitudes about conservation and available labor contributed most significantly to farmers’ intentions to adopt or maintain agroforestry. Overall, perceived behavioral control proved to have the most significant correlation with farmers’ intentions to adopt or maintain agroforestry. Therefore, agroforestry development programs could benefit from focusing on farmers’ perceived control of certain behaviors to enhance the persistence of agroforestry practices.  相似文献   

20.
Agroforestry is a promising method for enhancing land-use sustainability in the Bolivian Andes. However, its benefits in terms of rural development are under-recognized due to gaps in understanding users?? perceptions while taking into consideration both local and global environmental goals. Our study aimed to narrow these gaps by developing an analytical framework for analyzing the site-specific socio-ecological factors and interactions related to local woody species and assessing their ecological, economic, and socio-cultural plant values in order to identify the most promising agroforestry species. The framework was then tested in an indigenous community at 2,760?C3,830?m?a.s.l., incorporating vegetation surveys, environmental studies, and interviews on plant functions. Ecological, economic, and socio-cultural values and the ecological apparency of plants were calculated, and detrended correspondence and principal component analyses helped to reveal the socio-ecological context of significant factors for plant distribution and uses. Results showed dominating seral woody species along an altitudinal gradient. Although shrubs were more ecologically apparent than trees, trees were perceived to be more valuable as the usefulness and cultural importance of species increased with plant height and timber availability. Phytosociological factors played a minor but still significant role in perceived usefulness. Schinus molle and Prosopis laevigata (<3,200?m a.s.l.), Polylepis subtusalbida (>3,200?m a.s.l.), and Baccharis dracunculifolia (both zones) were evaluated as most promising for agroforestry use. In conclusion, our analytical framework proved to be a valuable tool for context-specific agroforestry plant selection. Nonetheless, economic, technical, and socio-cultural limitations of cultivating native agroforestry species were revealed as well. Agroforestry science and practice should, therefore, focus on enhancing reproductive potentials of existing woody vegetation, as well as problem-oriented horizontal dialogues between indigenous, expert, and scientific actors.  相似文献   

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