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1.
This paper deals with the construction and use of a simple linear supply and demand model. The main advantages of using such a model is firstly that everything is formulated and understood in the fundamental concepts of economic theory, and secondly that the model is easy to use in simulating various scenarios. It is not an alternative to larger and more sophisticated models, but can sometimes be a useful complement. It is formulated so that it can give simple and robust answers what will happen to production, consumption and trade if demand and supply change. It is easy to use regardless of the number of regions involved.  相似文献   

2.
This paper examines the potential and the cost of promoting forest carbon sequestration through a tax/subsidy to land owners for reducing/increasing carbon storage in their forests. We use a partial equilibrium model based on intertemporal optimization to estimate the impacts of carbon price (the tax/subsidy rate) on timber harvest volume and price in different time periods and on the change of forest carbon stock over time. The results show that a higher carbon price would lead to higher forest carbon stocks. The tax/subsidy induced annual net carbon sequestration is declining over time. The net carbon sequestration during 2015–2050 would increase by 30.2 to 218.3 million tonnes of CO2, when carbon price increases from 170 SEK to 1428 SEK per tonne of CO2. The associated cost, in terms of reduced total benefits of timber and other non-timber goods, ranges from 80 SEK to 105.8 SEK per tonne of CO2. The change in carbon sequestration (as compared with the baseline case) beyond 2050 is small when carbon price is 680 SEK per tonne of CO2 or lower. With a carbon price of 1428 SEK per tonne of CO2, carbon sequestration will increase by 70 million tonnes of CO2 from the baseline level during 2050-2070, and by 64 million tonnes during 2070–2170.  相似文献   

3.
This study applies an intertemporal partial equilibrium model of the U.S. Forest and Agricultural sectors to assess the market, land use, and greenhouse gas (GHG) implications of biomass electricity expansion. Results show how intertemporal optimization procedures can yield different biomass feedstock portfolios and GHG performance metrics at different points in time. We examine the implications of restricting feedstock eligibility, land use change, and commodity substitution to put our results in the context of previous forest-only modeling efforts. Our results highlight the importance of dynamic considerations and forest and agricultural sector interactions on projecting the GHG effects of biomass electricity expansion in the U.S.  相似文献   

4.
This study examines the effects of different coal, natural gas and carbon emission prices and market situations on the use of wood for electricity and heat production in the European Union. The analysis is carried out using the global forest sector model EFI-GTM expanded to cover electricity and heat production from wood, coal, natural gas, wind and solar energy. Analysis shows that with low coal and gas prices, use of wood for energy will be limited to low cost logging residues. With high coal, and especially natural gas prices, industrial wood also comes to be used for energy. At a carbon price of 100 €/tCO2, some 32 Mm3 of industrial wood, in addition to 224 Mm3 of logging residues, are projected to be used for electricity and heat in the EU region (including Norway and Switzerland) in 2030. The relatively low quantity of industrial wood used by the energy sector despite the collapse of the use of coal is explained by the fact that under high CO2 prices, other energy forms like natural gas, solar and wind energy become more and more competitive. However, the amount of industrial wood used for energy may substantially increase with subsidies for using wood for electricity and heat, even with relatively low carbon prices. With a high coal and gas price and a carbon price of 100 €/t, a subsidy of 30 €/MWh to the wood based and coal with wood co-firing electricity production will have a significant impact on the European wood based sector. Depending on the development of the market demand for forest industry products, such a subsidy may cause a 10–12.5% reduction in forest products production, a 6–9% increase in harvest level, about 30–60% increase in the pulpwood prices, and a 6–9 fold increase of wood imports in the EU, compared to the respective case without a subsidy in 2030.  相似文献   

5.
Objectives(1) To quantify the contribution of the French forest-wood product chain in terms of carbon sequestration and substitution when accounting for both the physical impacts (shifts in tree growth and mortality rates) and the market impacts (increased demand of harvested wood products (HWP)) of climate change (cc) and the subsequent forest managers adaptations; (2) To assess the uncertainty of the impacts on the above carbon balance and on forest allocation; and (3) To assess the role of managers’ expectations toward these future, uncertain but highly anticipated, impacts.MethodologyWe used a bio-economic model of the French Forest Sector (FFSM++) that is able to consider and integrate: (a) the effects of climate change over forest dynamics; (b) forest investment decisions (among groups of species) according to expected profitability; and (c) market effects in terms of regionalised supply, consumption and trade of HWP, depending on the forest resource stocks and international prices. By including both forest dynamics and forest products, we can evaluate the carbon balance taking the following elements into consideration: (a) carbon sequestered in live and dead biomass in the forest; (b) carbon sequestered in HWP; (c) carbon substituted when wood is used in place of fossil fuels or more energy-intensive materials; and (d) carbon released by forest operations.ResultsWhen the model is run at constant conditions for the next century, the average carbon potential of French forests is 66.2–125.3 Mt CO2 y−1, depending on whether we consider only inventoried wood resources, HWP pools and direct energy substitution, or if we also account for the carbon stored in tree branches and roots and if we consider the more indirect, but also largely more subjective, material substitution. These values correspond to 18.3% and 34.7%, respectively, of the French 2010 emissions (361 Mt CO2). However, when we consider both the probable increment of coniferous mortality and changes in forest growth, plus the rise in HWP demand worldwide, the average sequestration rate of the French forest decreases by 6.6–5.8% to 61.8–118.0 Mt CO2 y−1. Running partial scenarios, we can assess the relative interplay of these two factors, where the price factor increases the HWP stock while decreasing the forest stocks (where the latter effect prevails), while the physical impact of climate change reduces both, but to a lesser extent. Considering short-sighted forest managers, whose behaviour is based uniquely on the observed conditions at the time decisions are made, we obtain a limited effect of the overall carbon balance but a relatively large impact on the area allocation of broadleaved vs. coniferous species.  相似文献   

6.
The establishment of deep-rooted perennial species and their processing for biomass-based products such as renewable energy can have benefits for both local and global scale environmental objectives. In this study, we assess the potential economic viability of biomass production in the South Australian River Murray Corridor and quantify the resultant benefits for local and global scale environmental objectives. We model the spatial distribution of economically viable biomass production in a Geographic Information System and quantify the model sensitivity and uncertainty using Monte Carlo analysis. The total potentially viable area for biomass production under the Most Likely Scenario is 360,728 ha (57.7% of the dryland agricultural area), producing over 3 million tonnes of green biomass per annum, with a total Net Present Value over 100 years of A$ 88 million. The salinity in the River Murray could be reduced by 2.65 EC (μS/cm) over a 100-year timeframe, and over 96,000 ha of land with high wind erosion potential could be stabilised over a much shorter period. With sufficient generating capacity, our Most Likely Scenario suggests that economically viable biomass production could reduce carbon emissions by over 1.7 million tonnes per annum through the production of renewable energy and a reduced reliance on coal-based electricity generation. Our analyses suggest that biomass production is a potentially viable alternative agricultural system that can have substantial local scale environmental benefits with complimentary global scale benefits for climate change mitigation.  相似文献   

7.
The effects of a transatlantic trade agreement on the global forest sector were assessed with the Global Forest Products Model, conditional on previous macroeconomic impacts predicted with a general equilibrium model. Comprehensive tariff elimination per se had little effect on the forest sector. However, with deeper reforms and integration consumption would increase twice as much in percent in the US as in the EU. Net trade decreased in the US more than in the EU while it increased in Asia. Consumers and producers’ welfare increased by $7000 million in the EU and $14,000 million in the US, but decreased in some third countries, especially in Asia.  相似文献   

8.
9.
In 2004 ten Eastern and Southern European countries will join the EU. Agriculture and agricultural policy is an important issue in this EU enlargement process, for several reasons. This paper assesses the implications of the enlargement process for agriculture and agricultural policies.  相似文献   

10.
Previous studies have reported significant gains from adopting the adaptive harvest strategy under conditions of timber price uncertainty. For the final harvest decision in even-aged stand management, the adaptive strategy typically means that a stand is harvested when the timber price is sufficiently high, whereas low prices are avoided by postponing the harvest. Such a harvest behavior may have significant impacts on the future price process, which in turn affects the landowner's profits. Moreover, it would certainly affect the timber-based industry and consumers. This paper assesses these impacts in a hypothetical timber market, using the Faustmann rule (FR) as a benchmark. The results show that changing from the FR to the reservation price strategy (RPS) reduces the supply of timber, thereby pushes up the price level. The RPS significantly reduces the short-run random variation of timber price. In the long run, both the mean and the variance of the timber price tend to stabilize. Depending on the anticipated price variation underlying the RPS, the expected timber price may be close to, or much higher than, the benchmark level, and the variance of price can be very large or very small. The welfare effect of the RPS is small if the anticipated variance of timber price used to optimize the RPS is small. If the anticipated variance of price is large, then the RSP leads to significant increase in the landowners’ profits and at the same time reduces the consumer surplus by a much larger amount.  相似文献   

11.
This article analyses price shifts after currency devaluation in the Ivory Coast using a time‐series modelling approach. Model results identify the liberalisation of the import‐rice sector as the key factor for the transmission of price effects. Fixation of the imported rice price as a social compensatory measure hindered the adjustment of prices in the first year after the devaluation. As soon as the price controls on imported rice were lifted, prices changed in favour of tradable goods. The findings in this paper hint at a possible trade‐off between the protection of vulnerable groups during the process of adjustment and the intended incentive effect.  相似文献   

12.
This study presents a model that determines the effect of current and future payments for carbon sequestration, proportion of wood that sequesters carbon in long-lived product and landfills, and amount of carbon in the wood, on the optimal current forest harvest age. Increased current and future prices of carbon would lead to a longer and shorter harvest age, respectively. Higher current prices of carbon could increase the supply of carbon at a decreasing rate due to longer harvest ages. Moderate prices of carbon would encourage landowners to maintain standing timber. Policies focused then on stimulating landowners to hold timber on forestlands may not necessarily imply higher amounts of sequestered carbon. Increased future values of carbon could imply a reduction of the current supply of carbon.  相似文献   

13.
The rapid expansion of non-grain production (NGP) on cultivated land is of increasing concern regarding grain security in China. Characterizing the developmental mechanism of different NGP types and their responses to current policies is essential for providing critical references for the improvement of cultivated land protection policy. This study was conducted to explore the driving forces of NGP expansion in Tongxiang during three periods (2000–2008, 2008–2012, and 2012–2015). We first mapped the distributions of four types of NGP using multi-temporal high-resolution aerial photos. Then, we identified the driving forces of different NGP types at the parcel level using multinomial logistic regression modelling with geophysical, proximate, neighbourhood and policy variables. Our results showed that the total NGP area in Tongxiang increased from 31.16 ha to 2491.84 ha from 2000 to 2015. Farming conditions, such as soil type and distance to rivers, contributed more than settlements networks to the expansion of NGP in the Tongxiang region. A continuous and significant neighbourhood effect was found among pond fish farming, nursery plantations and duck rearing, demonstrating the strong stimulation of converted NGP parcels to surrounding farmers. Surprisingly, the implementation of policies such as basic farmland and standardized farmland failed to inhibit and actually encouraged NGP expansion. The planning of the main-functional region of grain production had a positive effect on inhibiting the expansion of some NGP types at certain stages. Our study provides valuable insights into the driving forces of NGP expansion at the parcel level and its response to current policies. This study supplements existing research to fully understand the phenomenon of NGP from the perspective of land use decision-making.  相似文献   

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