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1.
Forest Law Enforcement, Governance, and Trade agreements between the EU and countries that grow tropical timber aim to complement, alter, or generate new regulatory mechanisms that ensure the legality of timber products. These regulatory changes affect pre-existing policies and practices within timber production networks. The Indonesian-EU Voluntary Partnership Agreement was signed in 2013, and legality verification is scheduled to become mandatory for all smallholders by the end of 2017. Using grower surveys conducted in the Jepara regency of Central Java (n = 204), we generate information on who Jepara smallholders are, what timber species they are growing, and how programs that provide free and discounted seedlings contribute to STP. We use these data to understand how STP operates and how Sistem Verifikasi Legalitas Kayu (SVLK), the Indonesian method for timber legality verification, will affect STP networks and producers. We find that resource provision and oversight of source documentation increase formalization within STP. Our discussion details four policy-relevant insights for promoting STP amid continued formalization.  相似文献   

2.
The Ministry of Environment and Forestry (MoEF) of Indonesia has recently started to implement legality verification as a policy instrument to combat illegal logging. Using theories of policy instrument choice, this paper attempted to shed light on the conditions under which the instrument choice takes place. Over the past few years, there has been a significant change in political perception on illegal logging. In fact, the problem has been brought forward as one of the most chronic forest problems in the country. At the same time, there has been growing dissatisfaction on the previous range of instruments and measures. In addition, MoEF decision to use legality verification heavily interacts with the trend on import legislations in a number of countries. In fact, the trend is still “more friendly” for Indonesian timber products than boycotts. Legality verification was also preferred due to its streamlined requirements, compared to the more comprehensive standards of sustainability certification.  相似文献   

3.
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   

4.
Biomass of a mature man-made forest in West Java, Indonesia, was estimated to evaluate the carbon sequestration potential of plantation forest in the humid tropics. Twenty plots, each 0.25 ha in area and containing one to six planted species over 40 years of age and with closed canopies, were selected. Trunk dry mass was estimated from trunk diameter, tree height, and bulk density. Maximum trunk diameter (122 cm) was observed in a 46-year-old Khaya grandifoliola C. DC. tree, and the tallest tree (51 m) was a 46-year-old Shorea selanica (DC.) Blume. The largest trunk biomass (911 Mg ha−1) was achieved in the plot composed of two Khaya spp. Among the plots composed of indigeneous Dipterocarpaceae species, the largest trunk biomass was 635 Mg ha−1. These trunk biomasses were larger than those reported from primary rainforests in Southeast Asia (e.g., 403 Mg ha−1 in East Kalimantan, 522 and 368 Mg ha−1 in Peninsular Malaysia). The large biomass in this forest suggests that, given favorable conditions, man-made forests can accumulate the quantities of atmospheric carbon that were lost by the logging of primary forests in the humid tropics.  相似文献   

5.
Farm household characteristics determine the success of programs promoting agroforestry systems and practices. This paper reports household and farm factors affecting the adoption of timber management practices by smallholders in the Gunungkidul region, Central Java, Indonesia. The research used three logistic regression analysis models—based on each household and farm characteristic, and a composite of both together—to identify the key factors influencing farmers’ adoption and management decisions, and their relative importance. A sample of 152 farmers who managed their trees primarily for timber production was compared to a sample of 115 farmers with similar socio-economic characteristics who did not. The household condition and composite models identified both on-farm and off-farm gross incomes as significant factors affecting farmers’ decisions to manage timber trees. The models confirmed that farmers with larger farms, and with higher on- and off-farm incomes, were more likely to manage their trees for timber production. These results have implications for extension programs that promote adoption of commercial timber management by smallholders in the case study and similar regions.  相似文献   

6.
Summary In a previous paper in this series it was concluded that the warp (twist, crook and bow) of structural timber products is of utmost importance for end-user satisfaction. In this paper, a study of the spatial variation of warp of fast-grown Norway spruce is presented. The material, 372 studs (45 × 70 × 2900 mm2), was cut from different radial and longitudinal positions in trees from two stands.The results indicated that twist and crook were at maximum near the pith. However, twist decreased much more rapidly with the distance from pith compared with crook. Crook associated with core studs was larger in the butt log than in the top log, while twist and bow in core studs appeared not to vary longitudinally. Heartwood formation in the butt log juvenile core did not diminish warp propensity. Twist was rather well correlated to the distance between pith and centroid of cross section. The ratio of grain angle to pith distance was the best parameter to predict twist. Presence of compression wood increased bow and crook significantly, while ring width, density and knot area ratio did not substantially contribute to explain warp variation.A moisture content change from 18% to 12% decreased the overall acceptability, expressed by stud grade yield, from 76% to 43%. Thus, timber products should be delivered at a moisture level close to the one expected in the finalized building in order to avoid excessive warp after delivery.The authors gratefully acknowledge the support from EEC Forest programme, Contract No MA2B-0024, from NUTEK project No 9100554 and from Södra Timber AB  相似文献   

7.
Summary The overall aim of this study and series of papers is to address the key variables for timber quality and to optimize the utilization of Norway spruce timber with respect to construction purposes. It is the end-user's degree of overall satisfaction that determines the quality of a product. Therefore, the performance of structural timber cannot solely be defined by mechanical properties. Geometric performance (warp) must be improved if timber is to continue as an important building material.An experimental study of the spatial variation in warp and bending properties of fast-grown Norway spruce is introduced. In this paper, the growth characteristics are presented as a function of stand and location in the tree. The knot area ratio (KAR) was considerably higher in the core (0.31) compared with timber closer to bark (0.21). The top log studs had higher KAR (0.38) than the corresponding butt log studs (0.31). The average grain angle was 3.5% ( 2°) and appeared not to vary radially. The presence of compression wood was much more common in the top log timber (75%) than in the butt log (44%). However, no consistent radial variation in compression wood was found.The authors gratefully acknowledge the support from EEC Forest programme, Contract No. MA2B-0024 and from Södra Timber AG from NUTEK project No. 9100554  相似文献   

8.
Summary Strength and stiffness together with some properties characterizing the stand and the growth of trees were studied. Specimens (45 × 70 × 2900 mm3) were cut from different radial and longitudinal positions, from fast-grown trees from two stands in southern Sweden. These trees had relatively large annual rings (4–6 mm) and were not representative of Norway spruce in Sweden but are an example of the intensivelymanaged stands which will probably constitute a substantial part of the raw material supply in the future.The results indicate that the mean values for strength and stiffness were lowest for the core studs and increased further away from the pith. This radial variation in strength and stiffness appears to be associated with the variation in ring width. Density alone, on the other hand, does not explain the radial variation but should be used together with either ring width or knot area ratio to explain the stiffness and strength respectively. The increase in the strength and stiffness of the core studs from the butt logs to the top logs was significant. Density alone was found to be the best variable to explain the longitudinal variation between the butt logs and the top logs. The heartwood formation in the butt log juvenile core appeared not to have a positive effect on strength and stiffness. The occurrence of compression wood, the magnitude of grain angle and the margin knot area ratio had only a minor effect on strength and stiffness.The authors gratefully acknowledge the support received from the EEC forest research programme, Contract no MA2B-0024, from NUTEK, project no 9100554 and from Södra Timber AB  相似文献   

9.
The Government of Indonesia (GoI) and the European Union (EU) have signed a Voluntary Partnership Agreement on Forest Law Enforcement Governance and Trade (FLEGT-VPA), which aims to prevent illegal timber products from entering the EU. This agreement recognizes a certification for timber products exported from Indonesia based on FLEGT-VPA standards and implemented through the timber legality verification system, Sistem Verifikasi Legalitas Kayu (SVLK). While the implementation of SVLK complies with the FLEGT-VPA, it has not dissolved pre-existing national systems for forest management and timber trade. Implementing SVLK standards amid multiple forest regimes causes redundancy of administrative procedures in forest management and timber trade in Indonesia. This redundancy, in turn, leads to decrease in cost efficiency, weak legitimation, and low effectiveness of the system, especially in community forests.  相似文献   

10.
Uncertainty factors related to inventory methodologies and forest-planning simulation computings in the estimation of logging outturn assortment volumes and values were examined. The uncertainty factors investigated were (1) forest inventory errors, (2) errors in generated stem distribution, (3) effects of generated stem distribution errors on the simulation of thinnings and (iv) errors related to the prediction of stem form and simulation of bucking. Regarding inventory errors, standwise field inventory (SWFI) was compared with area-based airborne laser scanning (ALS) and aerial photography inventorying. Our research area, Evo, is located in southern Finland. In all, 31 logging sites (12 clear-cutting and 19 thinning sites) measured by logging machine in winter 2008 were used as field reference data. The results showed that the most significant source of error in the prediction of clear-cutting assortment outturns was inventory error. Errors related to stem-form prediction and simulated bucking as well as generation of stem distributions also cause uncertainty. The bias and root-mean-squared error (RMSE) of inventory errors varied between −11.4 and 21.6 m3/ha and 6.8 and 40.5 m3/ha, respectively, depending on the assortment and inventory methodology. The effect of forest inventory errors on the value of logging outturn in clear-cuttings was 29.1% (SWFI) and 24.7% (ALS). The respective RMSE values related to thinnings were 41.1 and 42%. The generation of stem distribution series using mean characteristics led to an RMSE of 1.3 to 2.7 m3/ha and a bias of −1.2 to 0.6 m3/ha in the volume of all assortments. Prediction of stem form and simulation of bucking led to a relative bias of −0.28 to 0.00 m3 in predicted sawtimber volume. Errors related to pulpwood volumes were −0.4 m3 to 0.21 m3.  相似文献   

11.
2000年《中华人民共和国种子法》的颁布和实施是我国林业发展和种苗事业的一个里程碑,是推进我国林业质量建设的根本保证。就林木种苗的依法治理和实现问题进行了探讨。  相似文献   

12.
2002年进口木材应如何打理   总被引:1,自引:0,他引:1  
自国家实施天然林保护工程以来,由于木材资源逐年减少以及行业内外对木材市场供需缺口加剧扩大的预期判断,致使木材进口数量逐年飞涨:1999年为630.8万m3(已经比1981年增长了7.5倍);2000年则为1361.2万m3;2001全年超过1500万m3。以上的统计数字仅为进口的各类原木,尚不含锯材、合板、单板和纸浆等。据统计,我国进口木材无论是数量或其总值都已列各种进口商  相似文献   

13.
通过对红皮云杉人工森与天然林木材主要材性指标的测定和比较,主要从材性的角度研究和探讨人工森红皮云杉木材主要利用途径。结果表明:红皮云杉人工森幼龄林不适宜作工种建筑用材,但成熟林可以替代天然林红皮云杉子相应的实木利用。人工林无论是幼龄材还是成熟材均适于作制浆造纸用材。  相似文献   

14.
1 Introduction Wood and charcoal belong to an energy convention which can sustain fluctuation in their status as a non-conventional fuel, coupled with their uncertain supply. Customers or users of firewood stem from a former era, which until the present, remain associated with simple communities, while the consumption of fossil fuels indicates an industrial society. Along with the progress in industrial development where markets can provide cheap and easy fuel, inherently sim- ple-community co…  相似文献   

15.
The purpose of this study was to investigate the strength properties of glued laminated timber composed of edge-glued laminae and to investigate the influence of edge gluing on the strength properties. Glued laminated timber composed of multiple-grade laminae (symmetrical composition, strength grade E95-F270, 10 laminations) was produced from karamatsu (Larix kaempferi) edge-glued laminae according to the Japanese Agricultural Standard. The bending, tensile, and compressive strengths of the glued laminated timber were measured. The average bending, tensile, and compressive strengths were 33.4, 24.5, and 35.9 MPa, respectively, and these values are almost equal to those of glued laminated timber composed of karamatsu single-piece laminae. It was determined that finger-joints and knots in the edge-glued laminae played a significant role in the failure of specimens. However, the use of glued edge-joints did not appear to affect the failure of specimens.  相似文献   

16.
A model was developed to estimate the stable timber output from shade stands of Cordia alliodora in coffee farms. The model predicts, for stand densities between 120–290 trees/ ha, timber yields of 9–24 and 6–15 m3/ha/yr of total and commercial overbark volumes, respectively. Current harvest rates in four sample farms are below these figures.The model is used to describe the transient trajectory (in terms of timber output over time) of Cordia alliodora stands with different initial DBH distributions. Practical recommendations are derived as to how farmers should manage their trees to achieve stable timber outputs in the shortest time possible.  相似文献   

17.
异氰酸酯树脂固定人工林杨木压缩变形的研究   总被引:3,自引:0,他引:3  
采用异氰酸酯树脂对人工林杨木进行表面密实化处理,目的是固定杨木的压缩变形,改善木材的材性。结果表明:随着水溶液中树脂质量分数的增加,木材的尺寸稳定性逐渐提高。  相似文献   

18.

Background  

Thornscrubs are a vegetation type from Northeast Mexico, consisting of 60 to 80 tree and shrub species that are used for a wide range of constructive, decorative and energy purposes. However, basic research of the physical and mechanical wood properties are still needed to establish additional uses and, thereby, increase their value in the timber industry.  相似文献   

19.
Abstract

The in situ assessment of timber structures has gained considerable attention in recent years due to some unexpected failures of public buildings. The assessment of timber, however, has been used in the evaluation of historic structures for a number of years, and the methods employed have evolved from visual observation (which is still one of the most effective ways of evaluating in situ timber) to more sophisticated methods that use various physical phenomena such as stress-wave or X-ray energy attenuation. In the health assessment of timber, effects of biotic elements such as insects and fungi are of interest, which, of course, is always connected with the presence of water in wood. The structural assessment encompasses questions related to the structural integrity of in situ members and the performance of components and the system. The structural health assessment not only focuses on biotic elements but also attempts to quantify engineering properties of the material such as strength degradation, modulus of elasticity, loss of cross-section, extent of checks, and other quantitative parameters needed for subsequent evaluation of the structural system, frequently expressed as load-bearing capacity. Service life planning of a structure is a complex issue that is related not only to the materials but also the environment and the use of the structure. Assessment of the health and properties of existing timber elements yields a piece of information that is necessary but not sufficient for the service life estimate. In the evaluation of structural timber, a mere use of various assessment techniques is not sufficient and usually an involvement of disciplines such as wood anatomy, wood physics, and statistics is needed. A reliable estimate of the parameters of in situ timber requires careful planning of measurements (experiments) since the material is highly variable and any statement about the properties of an element or even the entire system must reflect the random character of the wood properties. This paper will summarize the state-of-the art methods used in the assessment of in situ timber and analyze the strengths and the weaknesses of selected methods. An attempt will be made to outline future directions in the development of in situ assessment methods.  相似文献   

20.
江西森林公园旅游资源丰富,但在省内各区域的分布不平衡,且各森林公园旅游资源开发起步时间各异,因此森林公园间的旅游发展现状存在较大的差异。基于旅游收入及其收入结构的差异性对江西国家级森林公园聚类分析,进行量化比较研究,探寻江西省整体森林公园的旅游发展格局,为江西森林公园的旅游产业发展规划提供参考依据。  相似文献   

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