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1.
Economics of wastelands afforestation in India,a review   总被引:2,自引:0,他引:2  
Balooni  Kulbhushan 《New Forests》2003,26(2):101-136
India has vast tracts of wastelands. Afforestation of these wastelands is one of the many alternative uses of such lands. Given the scarcity of capital in India, it becomes imperative to determine the economics and financial feasibility of wastelands afforestation projects. The studies reviewed in this paper deal with cost and financial feasibility analysis of wastelands afforestation projects in India. The main rationale behind this review is to examine the prospects of increasing investments in the afforestation projects. This also has a global significance, since afforestation augments carbon sequestration, which has become an exigency in view of externalities associated with global warming. The study uses review of existing literature and regression analysis as analytical tools. The review reveals that reclamation of wastelands through afforestation is not an expensive venture in India. Afforestation projects are financially viable even when no environmental benefits are taken into consideration. The results of the study suggest that polluting companies/countries should explore the possibility of investing in afforestation in India to gain carbon credits economically, once the parties to the Kyoto Protocol to the United Nations Framework Convention on Climate Change decide to approve it. The studies reviewed reveal that researchers have used different sets of criteria for financial feasibility analysis of the afforestation projects. Almost all the studies have ignored non-market benefits of afforestation projects. Such methodological differences need to be addressed in view of the increasing importance of plantations as carbon sinks. Some socioeconomic issues like investment in tree crops vis-à-vis agricultural crops, preference for mixed plantation and wastelands development as a means of resource development have also emerged from this review.  相似文献   

2.
In this study, a forestry profit model for carbon dioxide (CO2) emission trading was constructed using southeast Georgia, USA, as the model area. The value of CO2 credits regarding forest stores of carbon was calculated using the stock changing method, the average storing method, the ton-year method, and the returning CO2 credit method. Based on this model, the CO2 price at which an afforestation interest rate reaches its maximum in each 5-year interval at a cutting age of 10–50 years was calculated, considering the influence on the cutting age by introducing emission trading. The cutting age at which an afforestation interest rate reaches its maximum was 32 years. The cutting age shortened with the rise of CO2 price in all four accounting methods. Assuming the dealing CO2 price, we can forecast what the present cutting age will be according to the stock changing method and the average storing method in regard to this model. Assuming this CO2 price and using the ton-year method and the returning CO2 credit method, we can forecast that the present cutting age is not going to change.  相似文献   

3.
Determining the optimal rotation period was a crucial component of forest sustainable management strategies, especially under climate change. This paper had two objectives: (1) to determine the economic benefits and optimal rotation periods for timber production when coupled to carbon sequestration, as predicted by time series prediction models for Pinus tabulaeformis plantations in China; and (2) to evaluate how different carbon prices and interest rates affected optimal rotation periods using the forest land expectation value. The results suggested that time series prediction models were valuable for estimating timber volumes and carbon sequestrations based on surveys of different-aged stands. Importantly, since integrating carbon sequestrations into timber production benefits did not increase optimal rotation periods, this should promote P. tabulaeformis plantation management. In the sensitivity analysis, a higher carbon price increased the profitability of carbon sequestration and timber production, but not optimal rotation periods, though they were reduced under higher interest rates. In conclusion, incorporating both timber production and carbon sequestration benefits would sharply increase forest-based revenues, while realizing the carbon sequestration potential of P. tabulaeformis plantations. This approach was clearly useful to the development of reforestation/afforestation projects trying to mitigate climate change and also provided a theoretical basis for sustainable forest management.  相似文献   

4.
刘正平 《湖南林业科技》2006,33(1):14-16,20
湖南省自2000年开展退耕还林试点,2002年在全省全面实施,6年来各地在退耕还林实践中创造出了一批成功的造林模式,取得了良好的生态、经济和社会效益。通过总结湖南省主要退耕还林造林模式的技术措施,分析其生态和经济效益,走生态、经济、社会共同发展之路,确保退耕还林工程“退得下,还得上,能致富,不反弹。”  相似文献   

5.
Patterns of afforestation on abandoned agriculture land in Latvia   总被引:1,自引:0,他引:1  
Abandonment of agriculture land and subsequent natural afforestation have been common features of the contemporary Latvian rural landscape, particularly in the period since 1990. This process affects the structure, ecology and visual qualities of the landscape. The study examines spatial characteristics of afforestation in relation to various environmental factors. The study was conducted in the central part of Latvia, where there is abundant abandoned agriculture land and a great variety of spatial afforestation patterns. The most typical patterns in this area were linear, mosaic, and continuous afforestation, as well as development of afforestation from the forest edge. The results of the study show that the spatial patterns of natural afforestation of abandoned agriculture fields can be very diverse, and do not follow the classical secondary succession model. Afforestation can be delayed by a dense cover of herbaceous vegetation for a period of up to 20?years. There are many interacting factors that affect succession and development of afforestation patterns, such as soil properties, size and configuration of fields, previous land use and also the random nature of plant colonization by seed. Further studies on afforestation patterns would help to understand better their ecological, economic and social effects as well as to determine optimal solutions for the use of abandoned agriculture land.  相似文献   

6.
The effects of historical land use changes on the global C cycle have mainly been studied by means of bookkeeping models. Here, we investigate with such models the impact of afforestation and deforestation on soil organic carbon (SOC) stocks. This approach, using field-based estimates of the response of SOC upon land use changes, is applied to a pilot area in the Belgian Ardennes over one and a half century (1868–2005). After a small initial decline during the 1868–1888 period due to deforestation for agricultural use, mean SOC stocks increased steadily up to 1990, due essentially to the conversion of deciduous to coniferous forests (in the study area, deciduous forests stored less SOC than coniferous) and the reclamation of heathland, which occurred both at the turn of the 19th and 20th centuries. Simulations showed that SOC stocks decreased recently (1990–2005) because of the slow down of sequestration in coniferous forests and a reversion of some of the coniferous plantations to deciduous forests. Over the entire period, afforestation resulted in a net sequestration of carbon (0.16 t C ha−1 year−1). Monte Carlo simulations demonstrated that the model was highly sensitive to its inputs (initial SOC stocks for each land use) both in term of predicted SOC stocks and rates of SOC stocks change. However, the sensitivity of the model was not large enough to revert the main trends of SOC changes observed. Compared to the amount of carbon sequestered in the biomass, the contribution of soils to the C sink in forest is small. Despite several sources of errors, a detailed reconstruction of land use changes combined with realistic SOC response curves upon land use conversion are required to be able to quantify the contribution of soils to terrestrial carbon fluxes.  相似文献   

7.
The concept and structure of the Spatial Decision Support System AFFOREST sDSS dealing with environmental performance (EP) of afforestation on agricultural land in northwestern Europe, is presented. EP is defined in terms of three environmental impact categories: (1) carbon sequestration (2) groundwater recharge and (3) nitrate leaching. The core of the sDSS is a raster based geographical database which allows for queries addressing 14 types of questions on where, how and how long to afforest in order to reach a desired EP or change in EP due to afforestation of the agricultural land. First the study area is differentiated according to the site conditions (based on soil texture, soil drainage, initial land use, yearly average precipitation, and yearly average N deposition. Then the EP for every site class is computed as a function of time using the VSAM metamodel. VSAM results from a conceptual simplification of an existing mechanistic point model, the forest process model SMART2. Input data for the metamodel are limited to the classified site conditions, the tree species used for afforestation, the afforestation strategy and the evaluation time. Besides limiting the data requirements, the metamodel approach allows for rapid and flexible computations on large numbers of pixel classes. Finally, depending on the type of question, the sDSS creates georeferenced outputs based on SQL-type spatial or attribute queries and more advanced multiple goal programming techniques.  相似文献   

8.
We extended the Hartman model to examine the optimal rotation, taking into consideration the economic benefits of wood and the dynamics of three carbon pools (aboveground biomass, dead organic matter, and harvested forest products). Chinese fir (Cunninghamia lanceolata) stands in Southern China were taken for a numerical example to analyze the effects of carbon price on the optimal management of short-rotation plantations. The results show that, with the current price of carbon, introducing the effects of harvesting on different carbon pools into the decision model would increase the optimal rotation age on poor (SI = 10) and medium (SI = 17) sites by one year, while it does not have any impact on the optimal rotation for good sites (SI = 21). Irrespective of site condition, the optimal rotation age is not sensitive to carbon price and interest rate. An increase in interest rate by 1% would reduce the optimal rotation age by one year. In conclusion, forest carbon trade could effectively enhance land owners' income from short-rotation forest plantations. However, it does not lead to any significant increase in forest carbon sink.  相似文献   

9.
This paper examines the first-best instruments for biodiversity maintenance in commercial boreal forests when landowners behave either in Faustmannian or Hartmanian way. Using an extended Hartman model, we show that biodiversity conservation requires both prolonged rotation age and leaving retention trees. While the former promotes some old growth species, the latter create new structural elements of decaying and dead wood, which can sustain a variety of saprolyxic species. A fully synchronized combination of retention tree subsidy and tax instrument is needed both to lengthen the privately optimal rotation period and to provide an incentive to leave retention trees. Using Finnish data we illustrate empirically the sizes of instruments. When combined with a harvest tax, the retention tree subsidy is 1000 and 750 € in the Faustmann and in the Hartman model, respectively. When used with a timber subsidy or a site value tax, the retention tree subsidy is 1700 €/ha in both models. The harvest tax rate varies over the range 40–65% in the Faustmann model and 20–40% in the Hartman model, while timber subsidy is between 0.5–1.0% and site value tax is about 1.75%.  相似文献   

10.
Afforestation is a stated goal in European Union policy and several member states have already implemented schemes to extend forest cover. However, little is known about the magnitude of non-market benefits of afforestation and how these benefits spatially differ. In this article, we propose a novel method to spatially explicitly predict marginal willingness to pay for afforestation. The approach is illustrated with data from a discrete choice experiment on local land use changes in Germany. GIS data on the respondent's place of residence allows inferring their current endowment with forest, which enters the utility specification of each respondent's status quo alternative. Marginal willingness to pay estimates therefore represent the value of changes in local forest cover relative to the observed status quo. This relationship can be utilized to predict willingness to pay at the county level. We find that marginal willingness to pay decreases as the current endowment with forest increases. The estimated optimal share of forest based on the average respondent's preferences is between 50 and 60%. The associated county level predictions of marginal and total willingness to pay can be used to inform national, regional and local policies that aim to increase forest cover.  相似文献   

11.
G. Singh   《Forest Ecology and Management》2009,258(11):2519-2528
Degraded Aravalli hills in western India require rehabilitation through resource conservation and afforestation for meeting the biomass needs of resource-poor tribes of the region. Rainwater harvesting treatments i.e., control, Contour trench (CT), Gradonie (G), Box trench (BT) and V-ditch (VD) were prepared in <10%, 10–20% and >20% slopes categories and Dendrocalamus strictus L. seedlings were planted in August 2005 with a view to conserve soil and water and increase the productivity of the hills. Soil water content (SWC), survival and height of D. strictus plants were highest (P < 0.05) in <10% slope and all these variables decreased with increase in slope. SWC increased by 27.45% and 25.68% in <10% and >20% slopes, respectively than in 10–20% slope. From lowest in control SWC increased by 11.95%, 20.21%, 17.61% and 11.49% in CT, G, BT and VD treatments, respectively. Growth variables were highest in VD plots but the increase in shoot number was highest (2.9-fold) in CT plots. Increase in effects of rainwater harvesting with time indicated by a change in production pattern from highest (P < 0.05) fresh and dry herbage in <10% slope in 2005 to 10–20% slope (24.66% and 26.09%) in 2006 and >20% slope (42.42% and 48.35%, respectively) in 2007. The increase in herbage was 1.17–2.40-fold in fresh and 1.20–2.52-fold in dry herbage over control. Highest (P < 0.01) production was in V-ditch plots. The treatments order for herbage production was C < CT < G < BT < VD. But the production was highest in BT in <10% and in V-ditch plots in 10–20 and >20% slopes. Conclusively, soil water status is affected by natural slope, stony soil surface and rainwater harvesting structures influencing seedling growth and herbage production. Box trench and V-ditch enhanced surface soil water facilitating herbage growth, whereas contour trench facilitated deep soil water storage, which was made available to the plants after monsoon. Thus rainwater harvesting practices enhanced vegetation cover and productivity of the degraded hills and can be replicated to conserve soil resource and increase biomass for rural poor of the region.  相似文献   

12.
中国大规模造林减少大气碳积累的潜力及其成本效益分析   总被引:8,自引:2,他引:8  
徐德应 《林业科学》1996,32(6):491-499
在对中国森林实行永续轮伐的假定下,计算了通过大规模造林来减少大气中CO2积累的潜力,并进行相应的成本-效益分析。首先把中国分成5个区,在每个区中选择4种造林或森林经营的方式,总计20种造林或森林经营的方式,根据现有可用于造林的土地面积的资料,对这些造成林或森林经营的方式进行计算。  相似文献   

13.
以典型三阶抽样和一阶抽样方法,建立调查样本,数据推算面积结果,全市现已完成绿化总面积8236hm^2,化树种丰富,城区、乡镇和道路的绿化投入大、起点高、对中山市乡镇和自然村四旁绿化进行抽样调查。以调查人均公共绿地48.27m^2。调查结果表明,中山市四旁绿配置合理,管护措施得力,绿化美化效果好。  相似文献   

14.
ABSTRACT

Soil erosion is a major socioeconomic and environmental problem in Turkey. Almost 86% of the land in Turkey has suffered various degrees of soil erosion. The objective of this study was to determine whether differences in tree species affect soil characteristics and microbial activity in degraded soils. Results from this study showed that organic C (Corg) was highest in the black locust soil at 0–20 cm depth and lowest in the bare land. Microbial biomass C (Cmic) increased in the order black locust > Scotch pine > bare land at two soil depths. One-way ANOVA demonstrated that afforested soils contain significantly higher microbial biomass C than those in the bare land soils. Microbial quotient (Cmic/Corg) of soils are positively influenced by afforestation as the bare land soils exhibited lower microbial quotient than the associated Scotch pine and black locust soils. Microbial communities in black locust soils were energetically more efficient—had a lower metabolic quotient (qCO2)—with a higher Cmic/Corg compared to those in Scotch pine soils. However, the microbial quotient in our study was still below range and cannot reach equilibrium again 15 yr after afforestation. Restoration of degraded lands could be a long-term process from microbial activity in the observed regions.  相似文献   

15.
This study examines the economic and spatial impacts of afforestation choices for carbon sequestration in Ontario, Canada when the non-permanence of forestry carbon offsets is taken into consideration. We test six scenarios including three long-term projects with red pine, Norway spruce and hybrid poplar plantations and three shorter term hybrid poplar scenarios that produce temporary carbon emission offsets. We convert the break-even costs of sequestering carbon to a permanent carbon offset equivalent and analyze the possible geographical implications of the choices across eastern, southern and central Ontario, Canada.The most financially viable scenarios show a relatively large part of central Ontario with attractive choices at a 4% discount rate but a much smaller area at an 8% rate. The assumption about the future price evolution of temporary carbon offsets is one of the biggest factors that influence the attractiveness of these choices. At the 4% discount rate and the assumption of rising prices of permanent carbon offsets, the scenarios that store carbon for long periods appear to be the least-costly option. Hybrid poplar appears as the best choice in southern Ontario and a mix of conifer species and hybrid poplar in the central and northern parts. When future prices of temporary carbon offsets are assumed to decline, temporary hybrid poplar projects appear to be more attractive in the southern and eastern parts of the province. The variety of alternative scenario choices also depends on the discount rate and future price expectations for temporary carbon offsets. For a relatively narrow deviation of the carbon offset price (±$0.6 t-1 CO2), only 4% to 9.2% of the total 5.8 million ha area would have one or more potentially viable alternative scenarios at the 4% discount rate and almost zero alternatives at the 8% rate. Higher discount rates lead to fewer attractive choices, suggesting that landowners would be left with very few options when trying to maximize net returns from plantations.  相似文献   

16.
Black spruce (Picea mariana (Mill.) B.S.P.) is the dominant tree species in the Canadian province of Québec’s boreal ecosystem, particularly in the black spruce-feathermoss (BSFM) domain (between the 49th and the 52nd parallels). While black spruce is generally well adapted to regenerate after wildfires, regeneration failure can sometimes occur, resulting in the irreversible conversion of closed-crown BSFM to open black spruce-lichen woodlands (OW). With OWs representing approximately 7% (1.6 M ha) of Québec’s BSFM domain, the afforestation of OWs carries significant theoretical potential for carbon (C) sequestration, which has not yet been evaluated. The main objectives of the study were then: (i) to estimate the theoretical C balance of OW afforestation within the closed-crown BSFM domain in Québec’s boreal forest; (ii) to calculate, using the life cycle analysis (LCA) method, all the GHG emissions related to black spruce OW afforestation in the closed-crown BSFM domain of Québec. The CO2FIX v. 3.1 model was used to calculate the biological C balance between the baseline (natural OW of site index 9 at age 50) and afforestation (black spruce plantation of site index 6 at age 25) scenarios, using the best estimates available for all five recommended C compartments (aboveground biomass, belowground biomass, litter, deadwood, and soil). The simulation revealed a biological C balance of 77.0 t C ha−1, 70 years following afforestation, for an average net sequestration rate of 1.1 t C ha−1 year−1. Biological C balance only turns positive after 27 years. When integrating the uncertainties related to both the plantation growth yield and the wildfire disturbance, the average sequestration rate varies between 0.2 and 1.9 t C ha−1 year−1. GHG emissions are 1.3 t CO2 equiv. ha−1 for all afforestation-related operations, which is less than 0.5% of the biological C balance after 70 years. Thus, GHG emissions do not significantly affect the net C balance of the afforestation project simulated. Several recommendations are made, mostly centered on the factors influencing the growth rate of carbon stocks and the impact of natural disturbances, to minimize the range of uncertainties associated to the sequestration potential and maximize the mitigation benefits of an OW afforestation project.  相似文献   

17.
Impact of stochastic price and growth processes on optimal rotation age   总被引:1,自引:0,他引:1  
This paper analyses timber harvesting in the Finnish economic and wood production environment. Empirical evidence including stumpage prices, silvicultural costs, etc., since 1949 covers all non-industrial private forestry. Stumpage price and volume growth processes are proxied by GBMs. Optimal harvesting age solutions and numerical results recognising price drift, price and growth volatility, volume growth, value growth and stand establishment costs, as well as thinning benefits, are provided for Scots pine. Moreover, comparative static and sensitivity solutions, including numerical results, show the impact of the discount rate, price drift, and price and growth volatilities on optimal harvesting age. Price volatility prolonged harvesting age by some 5–9 years, and growth volatility by about 1–2, but negative price drift for discount rates from 5 to 2% fell by roughly 6–10 years. Ignoring the future thinning benefits prolonged the harvesting age only by 1–2 years, but ignoring future stand establishment costs reduced it by 2–4 years. Including the price drift and volatility violated the 70 year age limit in the Forest Act for discount rates exceeding 3.5%. The recommended harvesting age of 80 years could be established only by ignoring the price drift. In all, this study produces solutions and programs that can be incorporated into a forest management planning software product widely used in Finland (Hynynen et al. in For Ecol Manage 207(1–2):5–18, 2005).
Markku J. PenttinenEmail: Phone: +358-10-2112244Fax: +358-10-2112104
  相似文献   

18.
采用不同播种时间、密度、营造林方式对观光木进行了栽培和营造林试验,结果表明:3月初是观光木播种育苗最佳时期;芽苗移栽平均苗高是直播苗的3.18倍,平均地径是直播苗的2.07倍;采用容器苗造林,成活率达95%以上,一年后高生长达112.1 cm,是裸根苗的1.77倍,地径是裸根苗的2.04倍;密度控制幼苗期以64株/m2为最佳,苗木合格率可达90.37%。  相似文献   

19.
This study explores the economic feasibility of several long-rotation afforestation scenarios for southern Ontario, Canada. Three species, red pine (Pinus resinosa Ait.), Norway spruce (Picea abies L.) and black walnut (Juglans nigra L.) are examined. We integrate growth and yield models, site suitability maps, and several management scenarios to investigate the investment attractiveness of these species inclusive and exclusive of carbon sequestration values. We report net present values (NPV), internal rates of return (IRR) and two break-even price metrics. For wood value only scenarios the IRRs range from 4.3 to 4.6% for red pine and 3.4–3.6% for Norway spruce (for the most attractive 10,000 ha, in a single rotation scenario). Black walnut had rates of return 3.5–3.7% for the most attractive 10,000 ha area. Adding carbon valued at Cdn $3.4 per metric ton CO2 − e (roughly 2005 prices in the Chicago Climate Exchange) increases rates of return by about 0.6% for red pine and Norway spruce and 0.4% for black walnut scenarios. Perhaps surprisingly these returns are comparable and better than 20-year rotation hybrid poplar plantations. To achieve a 6% real rate of return break-even carbon prices were $10.7/t CO2 − e for red pine, $12.6/t CO2 − e for Norway spruce and $17.2/t CO2 − e for black walnut (again for the “best” 10,000 ha). Although somewhat unremarkable, the results suggest that these longer-rotation species may be a better investment than perhaps previously expected if landowners have the appropriate site conditions.  相似文献   

20.
武定县干热河谷地区包括东坡乡等7个乡镇1365.9km^2,由于立地条件差,气候干热,因此造林成活率低。自1999年以来,随着中德合作造林、天保工程、退耕还林工程的实施,其造林成活率达91.9%,保存率89%。文章总结了历年造林中成功的经验、失败的教训,认为采取良种壮苗、树种选择、集水保墒、适时造林、加强抚育等措施,干热河谷地区的造林会获得成功。  相似文献   

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