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1.
The paper presents evidence, collected mainly through interviews with farmers in north-west India, regarding crop losses suffered by the farmers planting Eucalyptus on farm bunds. Farmers experienced that the crop remained weak in a width of strip measuring 2 to 10 metres next to the tree line. These losses drastically reduced the profits farmers were expecting from the sale of trees. The average B-C Ratio at 15% discount rate would have been 9.2 without these losses, but came down to just about 2, when crop losses were taken into account. The reduced profit margin was not perceived to be sufficiently high to cover risk of production and of fluctuating output prices, and therefore none of the farmers replanted Eucalyptus after sale. Many even uprooted the coppice roots and went back to annual cropping.  相似文献   

2.
Over the years farmers of Japanese descent in the Brazilian Amazon have planted indigenous trees that yield various products and services: fruit, seeds,bark, latex, oil, and shade and wind breaks for understory crop plants. Production of timber is often the intended end use of such planted trees. Long-term growth performance of these trees nevertheless has not been well documented. The authors constructed 65-year growth curves for nine indigenous tree species based on measurements of diameter at breast height (dbh), height, and tree age data provided by farmers in the Brazilian State of Pará. An index of wood prices used to calculate state stumpage taxes was then applied to mean stem wood growth curves to produce price curves. These price curves estimate both present value of standing timber, and the value added from annual growth of standing timber in the agroforestry systems studied. The results of this study provide local farmers with a tool to estimate potential annual income from the growth of their trees, and a basis for planning timber harvest rotations. This study's approach may be applicable in other parts of the tropics, where growth information about indigenous trees commonly used in agroforestry is lacking.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

3.
印度开展社会林业的基本经验是:(1)注重近期经济效益,其主要作法是,选用多用途树种,多种树种混交造林和集约经营;(2)积极引进并充分利用国际援助资金。文章还介绍了印度社会林业的实施效果及存在的问题。  相似文献   

4.
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   

5.
桉树人工林与其它林地土壤酶活性的差异分析   总被引:1,自引:0,他引:1  
研究了桉树萌生林、桉树植苗林、灌草丛和马尾松林地土壤中过氧化氢酶、蔗糖转化酶及脲酶的活性变化。结果表明:桉树萌生林、桉树植苗林与灌草丛、马尾松林地土壤中3种酶活性的差异不显著,说明栽植桉树对林地土壤酶活性没有显著影响。  相似文献   

6.
浙江省龙游县是"中国竹子之乡",竹笋产业是当地的一大支柱产业,是竹林增效、竹农增收的重要途径。以龙游县具有代表性的竹笋收购与销售企业"龙游竹海鲜笋专业合作社"为案例,调查分析了龙游县2010-2016年竹笋收购期限、收购价格、竹笋产量的年度变化以及竹笋的销售渠道,以期为竹笋的生产、销售以及竹林的定向培育提供参考。调查结果显示:龙游县竹笋产量大小年比例失衡,大年产量为小年产量的11倍;冬笋价格主要受季节、气候、产量、市场的影响,春笋价格则与笋加工企业的经营状况密切相关;竹笋加工产品单一,加工方式原始;竹笋产品销售渠道较为狭窄。因此,建议龙游县应加强竹林经营,逐步调整竹林的大小年结构,进一步拓宽笋产品销售渠道,加强竹笋深加工技术的研究与开发。  相似文献   

7.
印度是个千年古国,在发展林业方面有着独到之处。几百年来印度林业经历了森林破坏阶段、巩固和保护阶段、开发和扩大阶段、集约经营阶段和生态林业阶段。作者对于印度发展社会林业、森林发展公司,以及缓解薪炭材危机所采取的对策作了重点介绍,同时还指出了存在的问题和采取的措施。  相似文献   

8.
普洱地区桉树人工林下植物种类调查   总被引:2,自引:1,他引:1  
桉树因其生长快、抗逆性强、用途广而被世界各国广泛种植。但随着规模化的种植,桉树人工林结构过于简单,林下植物多样性下降等问题不容忽视。通过对普洱市桉树人工林下植物种类的调查,发现桉树人工林下植物的结构为灌木—草本类型和纯草本类型:灌木层主要以紫金牛科、野牡丹科、锦葵科、蝶形花科等植物占优势;草本层则是以菊科、禾本科、蕨科等植物为主要优势种。这些植物多属当地先锋植物或耐旱种类,而非地带性森林植被下的常见组成种类。  相似文献   

9.
This study analyses the economic aspects of a eucalypt-based agroforestry system established in the savanna region of Brazil. In 1993,eucalypt clones were planted at a spacing of 10 × 4 m, to facilitate their future association with crops and pasture grasses. The results show that the establishment and maintenance costs represent 37% of the total costs associated with the system. More than half of the revenues are from the sale of the wood products obtained in the 11-year rotation. Variations of ±20% of the sale price of the cattle significantly affected the sensitivity analysis, closely followed by the variations of the price of wood for lumber and energy. Variations of ±20% of the establishment costs of the forest component significantly affected the economic indicators. The viability of the system is also sensitive to a slight change in interest rate. Finally, the agroforestry system adopted by the company is economically more attractive than eucalypt monoculture.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

10.
Two surveys were carried out at Dibandiba, a semi-arid site in central Ethiopia, and Aleta Wendo, a sub-humid site in southern Ethiopia, to assess farmers' attitudes toward and perceptions of tree planting, levels of social forestry and uses of tree products. At Dibandiba, farmers planted mostlyEucalyptus camaldulensis trees, exclusively on homesteads andAcacia albida was left on farmland. Trees were planted mainly for construction (32%), fuelwood (29%), shade (11%) and cash (11%). Major (85%) uses were fencing, fuelwood, construction and plough handles. Dung was the major source of fuel (56%). At Aleta Wendo, planting consisted ofEucalyptus globulus mostly on private woodlots and homesteads, ofMilletia ferruginea andCordia abyssinica on farms, and ofEuphorbia abyssinica on fences and boundaries. Avocado and pears were also planted. The uses were the same as at Dibandiba. Major constraints were lack of seedlings and shortage of land at both sites, plus shortage of water at Dibandiba. Also, a review of information obtained from previous surveys on household composition and income, farm holding, cropping pattern, livestock composition and the use of labour was made.  相似文献   

11.
12.
尾叶桉为高大乔木,其生长快、干形通直、材性好,原始分布于印度尼西亚.我国自1976年开始引种尾叶桉,分别在广东、广西、海南等地建立了种源/家系试验林,保存了大量的遗传资源并营造了大面积的人工林,现已成为我国推广栽培面积最大的桉树树种之一.桉属树种全部为外来引进树种,我国没有自然分布,不能与我国本土树种发生杂交,不存在与我国本地树种发生基因交流或杂种化的风险.桉树在我国能正常开花结实,但种子特别小,很难自然发芽成活,不能自然更新和扩张,不会出现自发入侵本地生态系统、占据其它树种栖息地、造成生物入侵危害的现象.桉树与其它植物的水肥竞争或化感作用导致其林下植被贫乏还存在争论,但我国华南地区年降雨量多,林下植被一般都很丰富,也有多种动物栖息.大量引种栽培试验也证明,桉树在我国华南一带种植对其它植物的化感作用不明显,桉树人工林的发展完全可以人为控制.  相似文献   

13.
采用随机区组设计对巨尾桉植苗林与萌芽林进行研究.结果表明:4~6 a龄植苗林保存密度、出材量及造林、采运、销售成本均大于萌芽林,而树高、胸径、单株蓄积、利润、年均利润及净现值小于萌芽林,两种更新方式林木的年均利润、净现值均先增大后减小,峰值出现在第5年,分别达7299.1元·hm-2·a-1、18166.5元·hm-2和7139.4元·hm-2·a-1、16073.4元·hm-2;6 a龄后植苗林连年生长量及经济效益逐渐大于萌芽林,且植苗林年均利润及净现值逐渐趋于平稳增长,而萌芽林生长后劲不足,其最佳主伐时间为5 a.  相似文献   

14.
15.
The commercial opportunities for sengon (Paraserianthes falcataria L. Nielsen) are expanding rapidly in Indonesia, but there remains a lack of supply for the processing industry of the desired volume and quality of timber for processing from this fast-grown tree. This article discusses recent analysis of the value chain of sengon in Indonesia to determine (i) who the stakeholders were and how each added value, and (ii) how the benefits were distributed among stakeholders. Information was collected from a mix of farmers (as tree growers) and other actors involved in the value chain. The research revealed two broad types of value chains for sengon–‘direct’ and ‘traditional’, with the potential increased income for farmers being as high as 35% when they use the direct approach, compared to the traditional approach. As expected, the further ‘downstream’ the position of the stakeholder in the value chain, the greater the monetary value added to the sengon timber and subsequent products. If farmers were to acquire a greater understanding of the market dynamics for sengon, they could better target the sale of their forest products to specific market segments and make forestry a more profitable enterprise. While village traders in the traditional value chain play an important role connecting small-scale tree growers to commercial markets, the sustained viability of their role is uncertain if more farmers adopt the ‘direct’ approach.  相似文献   

16.
The introduction of carbon finance as an incentive in forestry farming has a potential of increasing the amount of carbon sequestered. However, this has created a daunting task among investors in forestry to optimise the joint production of wood and carbon sequestration. For instance, investors might find it profitable to give up some timber returns in exchange for carbon credits. This study evaluated expected income from growing Cupressus lusitanica Mill., Pinus patula Schiede ex Schltdl. & Cham., Eucalyptus saligna Sm. and Juniperus procera Hochst. ex Endl. for wood and/or the carbon market in central Kenya. The global average unit price of carbon and stumpage royalty were used to estimate expected returns from sale of carbon credits and wood, respectively. There were significant differences (p < 0.01) in the expected amount of income from sale of carbon and wood among the four species. Specifically, at economic rotation of 30 years with stand density of 532 trees ha?1 P. patula and C. lusitanica yielded US$28 050 and US$23 650, respectively, from sale of carbon compared with US$59 000 and US$51 000, respectively, from sale of wood. This was twice the value investors receive from clear-felling as compared with sales from carbon. Similarly, at economic rotation of 33 years with stand density of 150 trees ha?1, a forest investor in E. saligna would earn US$15 400 from sale of carbon compared with US$33 000 from sale of wood. Overall, the amount expected to be realised from sale of carbon was lower compared with that from sale of wood. This demonstrates that the price dynamics of carbon offsets in the voluntary and the compliance markets need to remain competitive and attractive for the forest owners to give up some timber returns in exchange for carbon income or to modify forest management regulation in order to increase carbon sequestration.  相似文献   

17.
Smallholder timber plantations may offer opportunities for farmers to increase their income. Nonetheless, such opportunities are often lost largely due to unfavorable regulations imposed on harvesting and marketing of timber. Adverse impacts are worsened because the regulations are not effectively communicated to smallholder farmers. We assessed the level of smallholder knowledge of existing regulations and found it very low. In part, this correlated to their socio-demographic characteristics. Poor literacy skills and a low level of education make it difficult for older farmers’ to increase their knowledge. This is compounded by the limited information channels that can reach the farmers. Improving smallholders’ knowledge by providing information concerning markets and regulations in a timely and clear manner could help smallholders exercise coping strategies and priorities when selling their timber that would in turn reduce the negative impacts of regulations. The roles of village authorities could be crucial. They are close to the smallholders and could channel the information. The government could provide training and incentives for them to be more active in communicating the regulations to the smallholders.  相似文献   

18.
1999年从澳大利亚引种巨桉,种植于西江林业局平岗林场,5年生时进行生长调查,结果表明:5 年生的巨桉平均树高达18.4 m,平均胸径15.2 cm,平均单株材积0.161 1 m3,最大胸径达24.1 cm,最高树高28.0 m,最大单株材积0.497 7 m3,平均蓄积量145.0 m3/hm2,与同时引种的立地基本相同的尾巨桉比较,优势较明显。平岗林场巨桉的引种取得良好的效果,适宜在广东西江两岸大面积推广种植。  相似文献   

19.
在山西省平顺县刘家村试验地对2011年从甘肃、陕西、四川、山西等地引进的5个2年生花椒品种的物候期进行了观测,以当地花椒品种为对照,初步了解了这些品种在试验区的生物学特征和生态适应性,掌握了其季相变化规律,研究结果表明,花椒物侯期的变化与自然环境因子密切相关;各品种在4月初萌动,4月中旬发芽,4月下旬至5月上旬叶片开始脱落;所有品种中狮子头的物候期明显较其它品种滞后6d~12d,其它品种的物候期无较大差异.  相似文献   

20.
以补贴到期后不再补贴为前提假设,运用Probit和Logit模型实证分析影响农户做出复耕决策的影响因素。结果表明:如果到期后停止补助受访农户中有复耕意愿的农户占53.46%,巩固退耕成果的难度依然较大;56.93%的农户对当前的退耕补贴政策持不满意或者非常不满意的态度,后续产业参与度不高。是否村干部、耕地总面积、退耕地面积、退耕地面积占耕地总面积的比例、对补贴的满意度、是否参与后续产业对农户复耕决策具有显著影响。访谈结果也表明,农户的复耕决策是在综合考虑收入预期和获得收益能力的基础上所做出的经营性决策;如果到期后停止退耕补贴而退耕土地又不能够直接为农民带来稳定的收益,或者退耕农户没有稳定的其他替代性收入,退耕农户将倾向于在补贴期后复耕。  相似文献   

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