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1.
Studies of land use policies are commonly based on the environmental impacts or on people's direct responses to the policies. However, research on the impact of policy implementation on people's livelihood and activities and the subsequent economic development of an area is incomplete. We selected Yanchang County as an example to track land use changes and their effects on the livelihood of the local population following the implementation of a new land use policy known as the Grain for Green Project (GGP). The data were collected from statistical yearbooks, questionnaire surveys, and satellite imagery from 1990, 2000, and 2008. We found that dramatic land use changes have occurred in Yanchang County. The vegetation coverage improved significantly from 1990 to 2008, as the grassland and forest areas increased from 44.1% to 60.1% and from 17.7% to 18.4% of the total land area, respectively. The cultivated land declined from 37.3% to 20.7%. With the agricultural area and grain production decreasing from 64 × 103 tons to slightly over 20 × 103 tons per year, an increasing number of local people sought employment in towns and cities. The non-farm income increased, and the local income structure shifted. Migrant and orchard worker income contributed the most to the balance of the total household income. We narrowed our focus to discuss how the GGP accelerated the changes in the participants’ lifestyles and what might be done to sustain the long-term effects of the GGP. While the GGP has brought about considerable environmental benefits, a comprehensive study of environmental–social systems is still needed to achieve a more efficient land use policy. The research results presented in this paper demonstrate that changes in land use and people's activities were triggered by policy changes. We aim to pave the way for studies on the “policy-land-use-social development” chain and to provide references for new policies.  相似文献   

2.
Natural vegetation enhances the value of agricultural landscapes for people and wildlife. However, the role of anthropogenic versus topographic factors in driving the extent of natural vegetation cover within agricultural lands at large spatial scales remains unexplored. I assessed the influence of anthropogenic and topographic variables on the extent of agricultural mosaics with high natural vegetation cover in the country of Turkey where a large extent of natural and semi-natural vegetation is maintained by traditional agriculture. GIS layers depicting human land use, elevation, slope, roads and population data were obtained and summarized at two spatial scales, within provinces and for 100 km2 grid cells covering the country’s entire agricultural land area. Average farm size was also obtained at province level. Hierarchical Partitioning was conducted to determine the independent effect of anthropogenic and topographic variables on the variation in agriculture with high natural vegetation. Slope had the largest independent effect on the variation in the proportion of agricultural mosaic with high natural vegetation cover. The extent of agricultural and settlement area also explained much of the variation in natural vegetation across both grid cells and provinces. The proportion of natural vegetation increased as human population and road density decreased across grid cells and as average farm size decreased across provinces. These results suggest that while topography is the primary driver of natural vegetation cover within agricultural mosaics in Turkey, the pressures associated with urban development and agricultural industrialization may also influence the cultural and wildlife value of agricultural landscapes.  相似文献   

3.
Urban river rehabilitation aims to enhance the ecological status of urban watercourses and promote measures for the local population to increase their well-being by making a direct or indirect use of the services these ecosystems may provide. The social and economic feasibility is evaluated by contrasting the resources used in the rehabilitation process with the benefits derived from it through the Cost-Benefit Analysis (CBA). By means of a case study, this work not only introduces the most innovative CBA approaches in environmental projects, but also implements probabilistic simulation methods in order to increase the robustness of the assessment indicators.The case study encompasses two projects, whose global costs total €46 M in 50 years, for the environmental rehabilitation of the stretch of the River Segura that flows through the city of Murcia. The benefits have been obtained by a contingent valuation exercise: €3.3 M/year (€0.6 M/year of use benefits, and €2.7 M/year of non-use benefits). Three different CBA approaches (economic, extended and dual) are applied to contrast these costs and benefits, conducting the analyses of uncertainty and sensitivity of the benefit items through a Monte Carlo simulation. The results highlight the importance of environmental benefits for this kind of projects to be socioeconomically feasible thanks to the profitability indicators they provide.  相似文献   

4.
Agriculture is the largest type of land use in the UK, accounting for about 77 per cent of the total area, compared with an average 50 per cent for the EU27. But in common with most high-income countries, agriculture's contribution to UK GDP and employment is low, at about 0.5 and 1.8 per cent, respectively, although the regional importance of the sector (and its associated food and farming industries) varies considerably.Of the 17.5 million ha used for agriculture, about 28 per cent is allocated to crops, and 67 per cent is grassland. The grassland includes 4.4 million ha of sole-owned rough grazing and 1.1 million ha of common land in mainly upland “disadvantaged areas,” primarily used for beef and sheep production. This has a major influence on land use, especially in the northern and western parts of the UK.From the 1930s until the mid-1980s, UK policy promoted increases in agricultural productivity to feed the nation from its own resources. An array of income and production support measures encouraged intensive farming, including a relative switch to arable farming in eastern areas. Since the early-1990s, policies have sought simultaneously to make UK agriculture internationally competitive and environmentally benign. These policies, evident in the Agenda 2000 Reforms of the Common Agricultural Policy, point the way forward for the future. It is likely that a greater distinction will emerge between policies to protect natural resources and enhance the flow of non-market ecosystem services from rural land, and agriculture and food policies intended to encourage an appropriate proportion of national food requirements to be met from domestic sources.It seems likely that over the next 50 years, the UK's land area will be required to deliver an increasingly diverse range of private and public goods to meet growing human needs and aspirations. This will require a balance of policy-driven goals and market forces. It will also need a much improved understanding of the trade-offs between food production and environmental goals and of the institutional arrangements required to achieve a balance of economic, social and environmental outcomes.  相似文献   

5.
We examine dramatic cropland expansion in Karamoja, Uganda by investigating the links between biophysical and political historical events leading to the current state of agricultural land use. Our objective was to quantify agricultural expansion, uncover the dominant drivers leading to the current state of agricultural land use and its impacts on livelihoods. Region wide analysis of remotely sensed data, land use policy and history as well as farmer interviews were undertaken. We posit that government programs instituting sedentary agriculture are the most significant drivers of cropland expansion in Karamoja. We show a 299% increase in cropland area between 2000 and 2011 with most expansion occurring in Moroto District (from 706 ha to 23,328 ha). We found no evidence of an increase in overall crop production or food security and food aid continues to be essential due to recurrent crop failures. Due to lack of resources for inputs (e.g., seeds and labor) cultivated fields remain very small in size and over 55% of once cultivated land is left fallow. Our findings bring into question whether continued promotion of rain-fed agriculture in Karamoja serves the best interests of the people. Current cropland expansion is directly competing and compromising pasture areas critical for livestock-based livelihoods. Without strong agricultural extension programs and major investments in climate-smart options, cropland expansion will continue to have a net negative impact, especially in the context of current climate projections which indicate a future decrease in rainfall, increase in temperature and an increase in the frequency and magnitude of extreme events.  相似文献   

6.
Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land.  相似文献   

7.
Grassland rental markets function as a venue for balancing production factors of herder households. This paper jointly determines the socioeconomic factors affecting herders’ grassland rent-in and rent-out behaviors by applying Bivariate Probit Model with clustering standard errors on 422 households’ data from Eastern Inner Mongolia. Results reveal that imbalances in “people-grassland (grass)-livestock-productive assets” are the major determinants of the herder households’ participation in grassland rental markets. Given other factors, an increase of 10 thousand yuan in a household’ productive assets renders an increase/decrease in their rent-in/rent-out participation likelihood by 1.0% and 2.0%, respectively; an increase of 100 standard sheep unit may bring about 4% increase in rent-in participation and 0.6% decrease in rent-out participation; an increase of 100 hm2 in hayfields may decrease and increase the likelihood of rent-in and rent-out participation by 13% and 3%, respectively; an increase of 1.0% in ratio of non-livestock income may decrease propensity of rent-in by 0.34%, and increase propensity of rent-out by 0.2%. In addition, the education and Chinese level of household head, and the available family labor encourage participation in grassland rent-in market. Main findings help facilitate better allocation of herders’ livelihood assets by participating the functional grassland rental markets.  相似文献   

8.
Zoning is one of the oldest policy tools for regulating private land use, but its effect on housing change is disputed. We define housing change as the difference over time in the number of housing units in a given jurisdiction. We conducted a cross-jurisdictional study of zoning effects on housing change, comparing zoned and unzoned townships in Michigan, USA (n = 709) after propensity score matching. Four-decade (1970–2010) panel models predicted zoned townships to have on average 2.2% fewer housing units a decade after zoning adoption compared to similar unzoned townships, but this effect was tempered by other variables. Higher-income townships had more housing units a decade after zoning adoption compared to higher-income unzoned townships, whereas lower-income townships with zoning had fewer housing units than similar unzoned townships. This study highlights the heterogeneous effects of zoning on rural and exurban housing change.  相似文献   

9.
The aim in this paper was to evaluate the spatial distribution of protected areas defined by law and their importance as structural corridors. The study area was 7,559,783.69 ha located in Western Bahia (Northeast Brazil), restricted to the limits of the Urucuia Group (Upper Cretaceous), where there is strong agribusiness growth. Currently, a major dilemma in Brazilian public policy arises from the conflicting interests of environmental conservation and increased food production. Brazilian environmental protection policies include the implantation of Protected Areas (Full Protection Units and Sustainable Use Units) and the adoption of the National Forest Act (Permanent Preservation Areas and Legal Reserves). In this context, we delimited illegal land-use in Permanent Preservation Areas (PPAs) adopting the intersection between land-use/land-cover data from PRISM/ALOS image classification for the years 2007–2010 and PPA vectors. We performed the temporal analysis in PAs considering land-use/land-cover data from Landsat TM image classification for the years 1988, 1992, 1996, 2000, 2004, 2008 and 2011. Finally, we performed a Morphological Spatial Pattern Analysis (MSPA) to evaluate whether PPAs alone are sufficient as structural corridors. Hypothetical scenarios were simulated to increase the potential of PPAs as structural corridors. The calculation of MSPA attributes was conducted considering 3 edge widths: 15 m (1 pixel), 510 m (34 pixels), and 1005 m (67 pixels). Four scenarios were simulated, considering a gradual increase in preserved areas. The results show that illegal land use is contained within PPA and protected areas. The scenario simulations present alternatives to increase the connectivity of the fragments and ensure the maintenance of ecological and hydrological services. Rapid agricultural expansion without proper landscape planning can compromise the sustainability of ecosystem services and the recharge zone of the Urucuia aquifer.  相似文献   

10.
Drainage and loss of wetland sites is a major problem of the agricultural landscape, as it reduces the landscape’s ability to retain water, nutrients, matter, and minimize erosion. With this in mind, the issue of the ability of wet sites to retain radionuclides and contaminated water in the case of a radiation accident was studied. In 2013, field research examined the occurrence of wetland retention sites in the emergency planning zone (EPZ) of the Temelín nuclear power plant (NPP; Czech Republic). As data sources, wetland biotopes (European network Natura 2000) were considered; in addition, retention features were field mapped, i.e. landscape elements of a wetland nature not normally considered nationally significant for conservation. Within the emergency zone, 2854.7 ha of wetland biotopes were registered and 318.9 ha retention features mapped. Density of retention sites (in ha/km2) per cadastre (local administrative units) was used to represent their spatial distribution within the zone. For an assessment of possible revitalization measures, leading to an increase in the landscape’s retention ability, spatial changes in the area of retention sites between 2013 and the mid-19th century, a period before extensive drainage of landscape occurred and a simplification of its structure, were mapped. Historic land maps (The Imperial Obligatory Imprints of the Stable Cadastre) were used as a basis of information on the occurrence and area of fens and wet meadows (4771.5 ha).For spatial comparisons of drained and undrained landscape in the past and present, the density of retention sites per cadastre was calculated. In the mid-19th century, 80% of cadastres had a density of retention sites exceeded 5 ha/km2; in 2013 only 40% of cadastres achieved this. In the most part, drained areas of the zone belong to the central part (around the power plant), as well as the EPZ’s eastern and south-eastern regions. From the density maps of retention sites, as well as from the stable cadastre imprints, it is possible to identify areas and retention features suitable for wetland restoration, thus leading to an increase in the retention capacity of the landscape in terms of water and radionuclide retention. Suggestions as to how to restore and turn retention features into semi-natural wetlands, as well as integrating small wetlands into an agriculture landscape are outlined.  相似文献   

11.
Scenario analysis of urban dynamics from spatial land use models can support urban, planning and policy. An integrated modeling approach, linking assessment of urban spatial dynamics, was applied to the Santiago Metropolitan Area (SMA). The integrated land use change model combines, a logistic regression model, Markov chain, and cellular automata. This model was calibrated with data, from 1975 to 2010, and was used to make predictions for the years 2030 and 2045, using two datasets of, urban and non-urban explanatory variables. Urban change estimates showed the highest fit during the, model calibration phase. The true-positive proportion and standard Kappa value (κ) were of 99% and, 0.87 respectively when validating against an urban cover reference map from 2010. Urban growth was, equal to +27,000 ha (72%) for the period 1975–2010, and the city of Santiago is projected to, reach approximately 93,000 ha by 2045 (+43% from 2010). In the SMA the most important, urban growth pattern is peri-urban development, referring to widespread boundaries and higher, fragmentation in peripheral municipalities. Predictions for 2030 estimate that ∼15% of the projected, urban expansion will occur outside the boundary set by the current Regulatory Plan proposal. These, results demonstrate the capacity of the integrated model to establish comparisons with urban plans, and its utility to explain both the amount and constraints of urban growth. The integrated approach of, urban dynamic assessment using land use modeling is useful for spatiotemporal representation of, distinct urban development forms.  相似文献   

12.
Livestock are an important element of the livelihoods of many Ugandan households, and considerable efforts at economic development by the government of Uganda have focused on the livestock sector. However, these development efforts have suffered due to a lack of detailed data on the distribution of livestock in Uganda to guide the targeting of such programs. In this paper, we use data from the 2008 National Livestock Census to develop a better understanding of where in Uganda there might be potential for significant investment to intensify the production of livestock and, conversely, where there are important challenges that need to be addressed, such as conflicts between human populations and livestock. This analysis is done by developing a quantitative model to predict mean livestock stocking rates at sub-county level (n = 929) that uses population density, agroecological factors, and market access as explanatory variables. A mapping of model residuals approach is then used to identify areas in Uganda that are relatively understocked and those that are potentially overstocked. This information is used to suggest approaches to livestock development in both types of areas.  相似文献   

13.
Effective soil and water management strategies require regional-scale assessment of erosion risk in order to locate prioritized area of intervention. Our study focuses on the Atacora mountain and surrounding areas (covering more than 18% of the total land area of Republic of Benin) which face a serious erosion threat despite their ecological and economic importance. To appraise the level of soil erosion risk of large area, we rely on the Instituto Nacional para la Conservación de la Naturaleza (ICONA) erosion model and use data from geographic information system (GIS). The erosion risk model requires four main inputs, namely, information on slope, lithofacies, land use and vegetation cover. The slope layer computed from ASTER digital elevation model (DEM) and the lithofacies layer inferred from digital pedogeological map are combined to draw soil erodibility map. To build soil protection map, we use land use/land cover layer extracted from LANDSAT 7 ETM + images in addition to vegetation cover layer derived from MODIS NDVI product. The final erosion risk map (with a resolution of 1 arc second) is obtained by overlapping erodibility and soil protection maps. We find that 21.8%, 58.5%, and 19.5% of the study area presents very low to low, medium, and high to very high level of erosion risk, respectively. Moreover, our findings are aggregated at the district-level (administrative unit). We observe that erosion risk is more acute in Boukoumbe district. Kerou, Kobli and Natitingou districts are mildly affected by erosion risk, while Kouande, Materi, Pehunco, Tanguieta and Toucountouna districts face a low risk. Ultimately, the proposed erosion risk map can help researchers and decision makers design and implement effective soil and water management interventions in the study area.  相似文献   

14.
Increased forest areas and climate change mitigation are policy goals enhanced by expanding private forest ownership. This study shows transfer of land from farms owning forested acreage associated with low quality land and high production costs achieves such goals. Calculated cost efficiency scores show a large gap between the most and least efficient farms, and farms with forests are less cost efficient. Land reforestation through subsidy programs could replace income from agricultural production. We illustrate that farms from the applied FADN panel could reforest 45,000 hectares, binding about 0.5 mln tons of carbon annually without limiting food or feed supply.  相似文献   

15.
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   

16.
目的 通过构建空间计量模型,实证检验2007—2018年我国农业技术进步对城乡收入差距的直接影响和空间溢出效应。方法 文章基于我国31个省(区、市,不含港澳台)的面板数据,利用空间杜宾模型,并设置邻接矩阵、地理距离矩阵和经济距离矩阵,分析农业技术进步对城乡收入差距的影响,并进一步将农业技术进步分解为农业前沿技术进步和农业技术效率。结果 (1)中国省域城乡收入差距具有显著的空间集聚特征,呈现出“高—高”和“低—低”的空间分布特征。(2)农业技术进步不仅有利于缩小当地城乡收入差距,还可以通过空间溢出效应促进邻近地区城乡收入差距的缩小。(3)农业前沿技术进步对当地城乡收入差距的缩小具有显著的促进作用,但对邻近地区的溢出效应不明显;农业技术效率则具有明显的空间溢出效应。结论 农业技术进步有助于缩小城乡收入差距。要继续加大农业科技投入,进行农业科技创新,提升农业技术效率,同时加强省际间的交流与合作,促使区域间农业技术的创新、转化与扩散。  相似文献   

17.
Between 2003 and 2013, sugarcane area expanded six-fold, from 142,000 ha to 847,000 ha, in Goiás State and the Federal District, Brazil. And while there has been much research on land-use dynamics of sugarcane expansion in established sugarcane growing regions, little is known about the dynamics associated with its expansion in sugarcane frontiers like Goiás. Understanding these dynamics provides critical information for environmental, economic, and political decisions. Here, we investigate the agricultural land-use change dynamics associated with sugarcane production in Goiás and interrogate the relationship between biophysical, institutional, and logistical factors associated with sugarcane expansion. Our results demonstrate that pasture is seven times more likely to be converted to sugarcane than soy, and most new sugarcane area was not sourced in native Cerrado vegetation. Although there exist few biophysical limitations to sugarcane expansion, capital, infrastructure, and institutions constrain production. Lastly, we show that areas where soy is currently cultivated may be converted to sugarcane in the future given the expansion of transportation and sugarcane infrastructure. Thus, we suggest incentivizing the cultivation of sugarcane on degraded pastures and supporting increased pasture stocking rates to ensure continued protection of both natural vegetation and food production while supporting the expansion of sugarcane in the state.  相似文献   

18.
Land greening in China is regarded as contributing a great deal to greening of the Earth. The phenomenon is mainly attributed to climate change, arising atmospheric CO2 and ‘Grain for Green’ (GFG) land management policies. However, limited knowledge is known how much land greening is from contributions of the GFG practice. Therefore, the study took the typical region of the GFG practice, the Loess Plateau, as the study area, and used 1982–2015 satellite-observed GIMMS3g normalized difference vegetation index (NDVI) data, ERA-Interim climatic variables (precipitation, temperature and solar radiation) and atmospheric CO2 concentration data with the help of a developed TPRC-based NDVI model to derive GFG-induced NDVI after 1999. Furthermore, this study tracked the spatial-temporal dynamics of GFG-induced NDVI and assessed contributions of the GFG practice to regional vegetation changes. Results showed that satellite-observed NDVI and TPRC-based NDVI both exhibited an increasing spatial pattern from the northwestern to southeastern Loess Plateau, but their greening trends were separately 0.0022 and 0.0009 per year in 1982–2015 (p < 0.05). Note that the satellite-observed greening trend was much steeper with a slope of 0.0056 per year after 2006 (p < 0.05). The subsequent analyses documented that GFG-induced land greening were largely responsible for the steep trend. In space, evident greening patterns began to be observed in the central Loess Plateau from 2006 to 2008, afterwards expanded towards eastern and southwestern Loess Plateau. In 2011–2015, the increase magnitude of GFG-induced land greening in the Loess Plateau averagely accounted for 8.5 % in comparison to estimated TPRC-based NDVI, but in six natural zones were various, ranging from 3.2%–15.7%. In some regions of central Loess Plateau, GFG-induced NDVI contributed even more than 20 % to vegetation increase. This study highlights that land use management contributes more to land greening dynamics over the Loess Plateau compared to climate change and arising atmospheric CO2 concentration. These findings likely provide some valuable information for curbing or enhancing specific-location vegetation changes in future regional land management and planning.  相似文献   

19.
A high level of fragmentation of farmland ownership is an important underlying cause of land degradation and, at the same time, an obstacle to sustainable land management. This study makes the first-ever analysis of long-term trends in the rate of fragmentation. Our study covers the period from the earliest stages of the current form of ownership patterns at the end of the 18th century until the present day. On the basis of significant predictors that have been identified (initial fragmentation, population growth, historical development of inheritance laws and of the land market, natural soil fertility and landscape type), we go on to project probable developments for the period from 2016 to 2045. A total of 102,984 land parcels in 56 cadastral units in the territory of Czechia have been analysed on the basis of data from four years (1785, 1840, 1950, 2015). Our study considers the development of two basic indicators of fragmentation – Mean Parcel Size and Number of Owners per 100 ha. The Mean Parcel Size has decreased over a period of 230 years from 1.08 ha to 0.64 ha, at a mean rate of −0.26% year−1. During the same period, the Number of Owners per 100 ha has risen from 17.50 to 79.66, at a mean rate of 0.61% year−1. A detailed analysis of the development trends confirms significant spatial variability and also time variability of the rates of the two indicators. The analysis also shows their mutual complementarity: growth in the rate of one of the indicators is usually accompanied by a drop in the other. The general trend that we project for the territory of Czechia in the upcoming 30 years is that there will be further diminution of the physical size of land parcels (continuing fragmentation of land parcels) accompanied by a reduction in the Number of Owners (defragmentation of land ownership).  相似文献   

20.
To assist pest management planning, the Canadian Forest Service developed the Spruce Budworm Decision Support System (SBW DSS), which quantifies the timber supply impacts of protecting stands against spruce budworm (Choristoneura fumiferana Clem.) defoliation. We incorporated protection costs and timber product values in this system to evaluate economic aspects of spruce budworm control. The analysis allows pest managers to evaluate the degree to which the traditional volume protection priority objective corresponds to three economic criteria, namely the volume protected per dollar protection program cost, the benefit–cost ratio of the protection program, and the net present value of the protection program. Twelve alternative spruce budworm protection strategies were analyzed on Crown License 1 in New Brunswick and Prince Albert Forest Management Area (PAFMA) in Saskatchewan, based on a number of protection program extents and intensities. For both landbases under base-case market conditions, the largest, most intensive protection scenario provided the highest amount of volume saved and net present value (at 3.94 Mm3 and $39.98 M for PAFMA, and 4.04 Mm3 and $41.49 M for License 1, respectively) while smaller, less-intensive programs provided the highest benefit–cost ratios and volume protected per present value dollar of protection cost (at 8.22 and 0.52 m3/$ for PAFMA, and 10.26 and 0.65 m3/$ for License 1, respectively). Sensitivity analysis on product values and protection costs revealed that smaller, less-intensive programs could also produce the highest net present values when costs are higher and/or product values lower. These results highlight the conditions under which pest managers should consider deviating from their traditional strategy of maximizing volume saved to one that maximizes the economic returns of protection.  相似文献   

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