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91.
作为贫困山区农业县,如何建立有效的“三农”支持投入机制,推进社会主义新农村建设,是县级财政面临的一个重要课题。建设社会主义新农村既是政府的责任.也是全社会的共同责任,财政应当好党委、政府的参谋,不断创新支持“三农”投入机制,鼓励和引导社会各方面参与新农村建设,形成推进社会主义新农村建设的强大合力。  相似文献   
92.
This study evaluated the impacts of partial cutting on stand characteristics, product recovery, and financial return in mature black spruce-balsam fir stands in Quebec. Four harvesting strategies (clearcut with advance growth protection, irregular shelterwood cutting leaving small merchantable stems, and two patterns of selection cutting) were each applied four times in 20 ha harvest blocks representing irregular black spruce-balsam fir stands. Before the four harvesting strategies were applied, there were no significant differences in stand characteristics (i.e., quadratic mean DBH, basal area, and merchantable stem volume) or expected product recoveries (i.e., lumber volume and value, chip volume and value, and total product recovery) estimated using the Optitek sawing simulation package. There was no significant difference in stand characteristics or product recovery values of the harvested stems between the selection cutting approaches (p > 0.05). However, significant differences in stand characteristics and product recovery values of the harvested stems existed between these treatments and both of the two other treatments. After cutting, the two selection cutting treatments had the lowest impacts on stand characteristics, as compared to the two other treatments. The selection cutting approach which used temporary skidding trails and where cutting was initially concentrated over half of the stand resulted in the highest benefit/cost ratio, relatively high net income and high total product value of residual trees.  相似文献   
93.
Timber investment returns were estimated for the principal exotic and selected native species in the Southern Cone of Latin America and in the Southern United States. Exotic eucalyptus plantations in South America were most profitable, with internal rates of returns (IRRs) ranging from 13% to 23%, followed by exotic loblolly pine, with IRRs from 9% to 17%. Average loblolly pine plantation returns in the US South were less profitable, with an IRR of about 9.5%, and natural forest management in the South had IRRs of 4% to 8%. Subtropical native species plantations of the best araucaria and nothofagus species had reasonable financial returns, with IRRs ranging from 5% to 13%. Subtropical or tropical native forests had fewer commercial timber species, and had much lower growth rates and returns. Their IRRs were less than 4%, or even negative for unmanaged stands. State subsidy payments for forest plantations or for timber stand improvements increased IRRs somewhat and reserving areas for environmental protection reduced their IRRs slightly. Including land costs in the cash flows decreased these internal rates of return substantially. Natural stand returns in Latin America were much less than those of plantations, but management of those stands offered better rates of return than only holding the land.  相似文献   
94.
林涛 《森林工程》2002,18(1):3-5
永安林业是林、工、商结合、产、运、贮一体的林业企业集团,主营业务包括:木(竹)材采运、加工、林化产品制造。许多经济技术指标,在我国森工企业中,处于领先水平。永安林业制定了向生物制药、环保产业发展的长远规则。从资源培育入手,提高产品的科技含量,提高资源利用率,扩大森林资源储备,把创新作为企业生存和壮大的根本发展战略。目前,经营业绩下滑是由于森林资源质量上降和市场替代产品使得杉木类木材利用价值减小造成。  相似文献   
95.
浅析债转股     
作者着重论述了债转股的积极作用与其存在的风险。提出了并冲所有企业都可以将债务转为股权。  相似文献   
96.
The economic viability and potential of a novel poultry agroforestry system   总被引:1,自引:0,他引:1  
Investigating agroforestry systems that incorporate poultry is warranted in Northern Europe as they may offer benefits including: improved welfare and use of range; reduced feed costs; price premia on products; reduced payback periods for forests; and, greater returns on investment. Free-range egg production accounts for 27% of the United Kingdom egg market and demand for outdoor broilers is increasing. No research has been conducted recently on the economic viability of agroforestry systems with poultry. An economic model was constructed to: assess economic viability of a broiler agroforestry system; and, investigate the sensitivity of economic performance to key factors and interactions, and identify those which warrant attention in research and management. The system modelled is a commercial trial established in Southern England in 2002 where deciduous trees were planted and broilers reared in six- or nine-week periods. The model uses Monte Carlo simulation and financial performance analyses run for a 120-year period. An Internal Rate of Return (IRR) of 15.5% is predicted for the six-week system which remains viable under a ‘worst case’ scenario (IRR of 12.6%). Factors which affect financial performance most (decreasing in magnitude) are prices achieved for broilers, costs of brooding houses, chicks, arks, feed and timber prices. The main anticipated effects of biological interactions on financial performance (increased ranging on feed conversion and excess nutrient supply on tree health) were not supported by analysis. Further research is particularly warranted on the welfare benefits offered by the tree component and its relation to price premia.  相似文献   
97.
98.
A study was conducted at Msekera Regional Agricultural Research Station in eastern Zambia to (1) describe canopy branching properties of Acacia angustissima, Gliricidia sepium and Leucaena collinsii in short rotation forests, (2) test the existence of self similarity from repeated iteration of a structural unit in tree canopies, (3) examined intra-specific relationships between functional branching characteristics, and (4) determine whether allometric equations for relating aboveground tree biomass to fractal properties could accurately predict aboveground biomass. Measurements of basal diameter (D10) at 10cm aboveground and total height (H), and aboveground biomass of 27 trees were taken, but only nine trees representative of variability of the stand and the three species were processed for functional branching analyses (FBA) of the shoot systems. For each species, fractal properties of three trees, including fractal dimension (Dfract), bifurcation ratios (p) and proportionality ratios (q) of branching points were assessed. The slope of the linear regression of p on proximal diameter was not significantly different (P < 0.01) from zero and hence the assumption that p is independent of scale, a pre-requisite for use of fractal branching rules to describe a fractal tree canopy, was fulfilled at branching orders with link diameters >1.5 cm. The proportionality ration q for branching patterns of all tree species was constant at all scales. The proportion of q values >0.9 (fq) was 0.8 for all species. Mean fractal dimension (Dfract) values (1.5?1.7) for all species showed that branching patterns had an increasing magnitude of intricacy. Since Dfract values were ≥1.5, branching patterns within species were self similar. Basal diameter (D10), proximal diameter and Dfract described most of variations in aboveground biomass, suggesting that allometric equations for relating aboveground tree biomass to fractal properties could accurately predict aboveground biomass. Thus, assessed Acacia, Gliricidia and Leucaena trees were fractals and their branching properties could be used to describe variability in size and aboveground biomass.  相似文献   
99.
Longer forest rotation ages can potentially increase accumulation of carbon in harvested wood products due to a larger proportion of sawlogs that can be used for manufacturing durable wood products such as lumber and plywood. This study quantified amounts of carbon accumulated in wood products harvested from loblolly pine (Pinus taeda L.) stands grown in Mississippi by extending rotation ages traditionally used to manage these stands for timber. The financial viability of this approach was examined based on carbon payments received by landowners for sequestering carbon in standing trees and harvested wood products. Results indicated a potential to increase carbon accumulated in wood products by 16.11 metric tons (t) of carbon dioxide equivalent (CO2e) per hectare (ha) for a rotation increase of 5 years and 67.07 tCO2e/ha for a rotation increase of 65 years. Carbon prices of $50/tCO2e and $110/tCO2e would be required to provide a sufficient incentive to forest landowners to extend rotations by 5 and 10 years, respectively. With 2.8 million ha of loblolly pine stands in Mississippi, this translates to a possible increase in wood products carbon of 45 million tCO2e and 80 million tCO2e for harvest ages increased by 5 and 10 years, respectively. Higher carbon prices lengthened rotation ages modestly due to low present values of carbon accumulated with long rotations.  相似文献   
100.
采用事件研究法对国内45家实施股权激励的公司进行实证研究,并采用市场调整法考察股权激励对股票价格的影响。结果显示:股权激励在公告日当天和公告日前一个交易日和公告日后一个交易日对股价有显著影响,有显著的正的收益。  相似文献   
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