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1.
This study aimed at identifying the problems and needs connected with builders’ use of wood products in building and renovation projects and developing a method to channel these needs into product innovation activities. It is built on the understanding that users of a wood product experience needs that may reveal themselves only when a product is used. Therefore, the empathic design was used to detect these needs. Two building contractors and two apprentices were studied for five working days at two renovation projects. In total, 11 product and service needs concerning wood products were identified. Most of the identified needs were related to the potential for time savings. The needs were later presented and discussed in a workshop with a team of persons from different parts of the wood product supply chain and innovation concepts were outlined. The workshop participants found the approach both informative (about hidden needs) and productive (by generating new product ideas). Although the results must be generalized with caution, the study indicates that an empathic design method, integrated with an idea-generating stage, is a suitable approach for product development in the wood sector.  相似文献   

2.
This paper demonstrates a Geographic Information Systems (GIS) procedure of classifying and mapping forest management category in Baihe Forestry Burea, Jilin Province, China. Within the study area, Baihe Forestry Bureau land was classified into a two-hierarchy system. The top-level class included the non-forest and forest. Over 96% of land area is forest in the study area, which was further divided into key ecological service forest (KES), general ecological service forest (GES), and commodity forest (COM). COM covered 45.0% of the total land area and was the major forest management type in Baihe Forest Bureau. KES and GES accounted for 21.2% and 29.9% of the total land area, respectively. The forest management zones designed with GIS in this study were then compared with the forest management zones established using the hand draw by the local agency. There were obvious differences between the two products. It suggested that the differences had some to do with the data sources, basic unit and mapping procedures. It also suggested that the GIS method was a useful tool in integrating forest inventory data and other data for classifying and mapping forest zones to meet the needs of the classified forest management system.  相似文献   

3.
We used a goal programming technique to determine the optimal harvest volume for the Iranian Caspian forest. We collected data including volume, growth, wood price at forest roadside, and variable harvesting costs. The allometric method was used to quantify seques- trated carbon. Regression analysis was used to derive growth models. Expected mean price was estimated using wood price and variable harvesting costs. Questionnaire was used to determine the constraints and the equation coefficients of the goal programming model. The optimal volume was determined using the goal programming method according to multipurpose forest management. LINGO software was used for analysis. Results indicated that the optimum volumes of species were 250.25 m3.ha-1 for beech, 59 m3.ha-1 for hornbeam, 73 m3.ha-1 for oak, 41 m3.ha-1 for alder, and 32 m3.ha-1 for other species. The total optimum volume is 455.25 m3.ha-1.  相似文献   

4.
5.

? Context

There are many stand property–density relationships in ecology which represent emergent properties of plant populations. Examples include self-thinning, competition–density effect, constant final yield, and age-related decline in stand growth. We suggest that these relationships are different aspects of a general framework of stand property–density relationships.

? Aims

We aim to illustrate the generalities and ecological implications of stand property–density relationships, and organize them in a comprehensive framework.

? Methods

We illustrate relationships between stand property and density (1) at one point in time, (2) over time, and (3) independent of time. We review the consequences of considering different variables to characterize stand property (mean tree size, mean tree growth, stand growth, stand yield, stand leaf area).

? Results

We provide a framework that integrates the broad categories of stand property–density relationships and individual expressions of these relationships. For example, we conclude that constant final yield is a special case of the growth–growing stock relationship for life forms were yield is a reasonable approximation of growth (non-woody plants).

? Conclusion

There is support in the literature for leaf area being broadly integrative with respect to various expressions of stand property–density relationships. We show how this is and suggest implications for plant population ecology and forest management.  相似文献   

6.
Past monoculture forestry in China has contributed to countrywide ecological disasters and economic difficulties in forestry regions. China‘s new forestry programs, Natural Forest Conservation Program and Returning Farmlands to Forests Program, provide opportunities for ecosystem management of mountain forests in China. A decision support system, FORE-STAR, has been developed for better managing and protecting natural forests in Changbai Mountain area. It uses GIS-based forest inventory data at a scale of forestry bureau. The first version contains two sub-modules: forest operation and forest res-toration. Under each sub-module, users can compare several decision options and make optimal choices. It can help field for-esters, forest managers, and policy makers make multi-objective and consistent decisions in planning forest management at hierarchical administrative scales.  相似文献   

7.
The increased concern for environmental values increases the complexity of long‐term forest management planning. Environmental issues have to be dealt with over space and time. By creating links between existing aspatial long‐term forest management models and geographical information systems (GIS), environmental issues can be treated within the forest management planning process. In this article, a spatial decision support system (SDSS) developed by incorporating a forest management planning model into a GIS is presented. A case study is employed to illustrate the usefulness of the SDSS using real data. In order to preserve the water bodies in a forest area, the allowable treatments in areas falling within certain distances of lakes, streams, and swamps were restricted. Treatment schedules were simulated for all stands, and linear programming was utilized to maximize the net present value (NPV) subject to a non‐declining felling path. The NPV was reduced by 6.9% due to the treatment restrictions, and the annual harvest flow was reduced by about 10%. Various thematic maps of future time periods may be produced for subjective evaluation of the results.  相似文献   

8.
We demonstrate a method for evaluating the appropriate number of samples required to estimate plant species richness in different forest types within a forested landscape. In each of 36 plots (0.1 ha each) from 5 forest types (deciduous broad-leaved secondary forest and 4 categories of coniferous plantation classified according to stand age) in central Japan, 40 quadrats of 1 × 1 m were set in a regular pattern; the total number of quadrats in each forest type ranged from 200 to 400. In each plot, the number of observed species in 40 quadrats ranged from 60 to 80% of the number of species estimated by the rarefaction method for each forest type. Sampling 30 quadrats detected approximately 90% of the observed species in each plot that were detected using 40 quadrats. In specific functional groups (i.e., tall trees and weed species), the ratios of both tall trees and weed species to all species were at equilibrium for 30 or more quadrats. For fewer than 30 quadrats these ratios were highly variable. No significant differences were found among forest types in the ratio of the observed number of species in each plot to the estimated number of species calculated using the rarefaction method, and in sampling efficiency estimated by use of non-parametric estimators. We concluded that the number of samples does not need to be changed according to forest type or plantation stand age in the studied landscape, and that the method used to evaluate the number of samples could be useful.  相似文献   

9.
In 1984–1986, 32P-labelled methamidophos was used to investigate the translocation, distribution and breakdown of this systemic insecticide after penetration into the ascending sap of spruce (Picea abies Karst.), following bark treatment with an adhesive paste of 15% active ingredient. The β-radiation of 32P permits a semi-quantitative measurement on the bark of standing trees as well as quantitative sample analysis and autoradiography. The following results are given: method of application and total 32P in the ascending sap; distribution of 32P in trunk cross-sections and in bark/needles; 32P in the killed beetles corresponding to the toxic dose, separation of methamidophos and breakdown products; halflife of breakdown in vitro and in vivo; and environmental implications. From the xylem, methamidophos penetrates into the phloem, but no 32P appears outside on the surface of the bark, so that only insects mining inside the bark are killed and no hazards for useful insects, birds and wildlife animals can arise. Traces of 32P were measured in air and water, and no 32P was found in the soil due to the translocation upwards only. The approximate oral toxicity of methamidophos to Ips typographus was estimated to be < 5 mg/kg and the half-life in spruce was 45 days (15°C), indicating a sufficient biological effectiveness over several months, preferably in areas of low average temperatures and in trees impaired by environmental pollution.  相似文献   

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