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1.
Although many different forest certification standards exist, harvest adjacency and green-up regulations are common to most certifying bodies. This study develops a means for evaluating trade-offs associated with implementation of nth-order adjacency and green-up constraints on a 1.7 million ha landscape in Oregon in the US. Depending on the type of adjacency structure and delay between harvests, the opportunity cost of the restrictions, estimated by the change in discounted sum of producer and consumer surplus in the regional log market, ranged from 0.25% to 66% (or US $60 million to $15.3 billion) of the unconstrained value. Increasing green-up delays beyond 30–40 years had little effect on estimated opportunity cost of the modeled restrictions.  相似文献   

2.
Tropical forests potentially contribute to global climate change mitigation through carbon sequestration, hence a global carbon pool. In order to mitigate the global climate change impact, the Kyoto protocol developed the clean development mechanism (CDM) which supports carbon credits for plantation activities in developing countries. Unfortunately, none of the CDM forestry projects included bamboo as a carbon reservoir. Although bamboo is an integrating part of tropical forest ecosystems, it was overlooked in the initial negotiating process. The present study, therefore, investigated the carbon storage potential of a common bamboo species, Bambusa vulgaris at Lawachara forest reserve of Bangladesh. Results showed that five-year-old B. vulgaris stand stored in total 77.67 t C ha−1 of which 50.44 t C ha−1 were stored in the above ground biomass (culms, branches and leaves), 2.52 t C ha−1 in the below ground biomass and 24.71 t C ha−1 in the soils. This amount of carbon storage is much more promising than the carbon storage of many other tree species considered in the CDM projects. These findings demonstrate the potential of B. vulgaris to be considered in CDM projects as a plantation species and thereby mitigate climate change impact more efficiently.  相似文献   

3.
Land use and cover (LUC) change is a major driver of ecosystem service loss worldwide. In response, policymakers have designed conservation strategies that incentivize the establishment and maintenance of LUC types associated with higher ecosystem service provision. Many of these policies also aim to promote social and economic goals such as reducing poverty. Attempts to measure the impact of policy-driven LUC change on stakeholders typically focus only on economic outcomes for landowning participants or aggregate the socio-economic outcomes of diverse groups. In this study, we applied local ecological knowledge (LEK) held by beekeepers in Costa Rica to understand the impact of policy-driven LUC change on this specific group of often non-landowning stakeholders. Beekeeping is a globally important rural livelihood and provides pollination services to crops and wild plants. We synthesized beekeeper LEK using a mixed-methods approach including apiary mapping exercises (n = 215 apiaries), questionnaires (n = 50 participants), and follow-up interviews (n = 21 participants). Our study revealed that some policy-driven LUC changes have limited beekeepers’ access to preferred land uses, such as secondary and mature forests with native trees. Participants reported concern for their livelihoods due to policy-driven spatial and temporal change of floral resources via the establishment of tree plantations, changes in pasture management, and laws that prohibit beekeeping in national parks and reserves. Our study provides evidence of unintended outcomes from land use policies, including Payment for Ecosystem Services, with disproportionate negative impacts on non-landowning residents who depend on natural resources in the landscape for their livelihoods. Our study illustrates potential inequality rising from current incentive mechanisms associated with Payments for Ecosystem Services and other conservation policies and calls for policymakers to consider LUC change impacts on non-landowning stakeholders.  相似文献   

4.
Reducing carbon emissions from deforestation and forest degradation now constitutes an important strategy for mitigating climate change, particularly in developing countries with large forests. Given growing concerns about global climate change, it is all the more important to identify cases in which economic growth has not sparked excessive forest clearance. We address the recent reduction of deforestation rates in the Brazilian Amazon by conducting a statistical analysis to ascertain if different levels of environmental enforcement between two groups of municipalities had any impact on this reduction. Our analysis shows that these targeted, heightened enforcement efforts avoided as much as 10,653 km2 of deforestation, which translates into 1.44 × 10−1 Pg C in avoided emissions for the 3 y period. Moreover, most of the carbon loss and land conversion would have occurred at the expense of closed moist forests. Although such results are encouraging, we caution that significant challenges remain for Brazil's continued success in this regard, given recent changes in the forestry code, ongoing massive investments in hydro power generation, reductions of established protected areas, and growing demand for agricultural products.  相似文献   

5.
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   

6.
Forest fragmentation is continued to be widespread in the tropics resulting in reduced ecosystem services including carbon storage. However, the effect of forest fragmentation is not considered in the current carbon policy. We investigated the effect of forest fragmentation on tree biomass carbon and soil organic carbon (SOC) storage in a moist tropical forest in Bangladesh. Above and below-ground tree biomass carbon were calculated by using widely accepted allometric equations and SOC was measured by sampling soils up to 10 cm depth and analyzing them in a soil laboratory. Results showed that carbon storage in tree biomass was significantly lower in fragmented forests (16.3 ± 1.37 t C ha−1) than in contiguous forests (31.21 ± 2.75 t C ha−1) (p < 0.001). Likewise, a significantly lower SOC was contained in the soils of fragmented forests (17.26 ± 0.83 t C ha−1) than in contiguous forests (21.62 ± 0.78 t C ha−1) (p < 0.001). Thus a total of 36% less carbon retained in tree biomass and soils in fragmented forests than in contiguous forests. Backward multiple linear regression analysis revealed tree density, tree height, tree DBH, height-diameter ratio (H/D) and tree species richness as influential factors of carbon variation in fragmented forests. All these structural parameters except tree species richness were significantly lower in fragmented forests, were positively associated with carbon storage and explained together 69% of the carbon storage variation. These findings suggest that the altered stand structure and tree allometry likely caused reduced carbon storage in fragmented forests and highlight the importance of landscape scale management intervention in the tropics. Here, we provided with the evidence of strong negative impact of forest fragmentation on carbon storage and argue that this effect should be in consideration which is currently overlooked in existing carbon accounting systems for tropical forests.  相似文献   

7.
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   

8.
Switchgrass is a perennial crop producing high amounts of biomass for good quality pellet production. The objective of this study is to examine the efficiency of different cultural practices of switchgrass for pellet production under field conditions for four different N-fertilization (0, 80, 160 and 240 kg ha−1) and two different irrigation levels (0 and 250 mm), in two soils in central Greece with rather different moisture status over the period 2009–2012. Moreover, comparison between three harvest methods (two different types of bales and silage) was made. The results derived from this study revealed that the bale at 22 kg is the harvesting practice with the highest costs while there was reduction of efficiency scores when nitrogen levels increased. At both environments the efficiency scores followed the same trend, confirming that low levels of nitrogen fertilization enhance the economic competitiveness of switchgrass production. Palamas site is the area where switchgrass for pellet production had positive income ranging from 400 to 1600  ha−1, while Velestino site had always negative. Therefore, places like Velestino with non-aquic soil should be avoided for switchgrass. These data suggest that growing switchgrass for solid biofuel production as energy crop is a worthwhile decision only in areas with a moderately shallow groundwater table (aquic soil) or maybe in high precipitation regions.  相似文献   

9.
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   

10.
Being fertile lands, wetlands have been managed for traditional agriculture over millennia. However, the integrity and ecosystem services of wetlands are being jeopardized by intensive land-use comprising of drainage and excessive disturbance. An adhoc and intensive use of wetlands, without preserving ecological integrity is causing ecosystem disservices and threatening conversion of a large soil organic carbon (SOC) sink into a net source. Wetlands in the tropical parts of the world are distributed unevenly and represent ∼3% of the total world land area. Due to stagnancy and even reduction in rice (Oryza sativa) yield of many agricultural regions, there is a need for additional and alternative land-uses which can raise the global rice production to ∼1 billion Mg (megagram = 106g = metric ton) by 2050 from ∼497 million Mg now. Wetlands can be a viable option to advance global food security because of high soil fertility and vast geographical distribution. A ‘3-tier rice production system’ is proposed herein based on specific hydrological niche to advance global food security without degrading the ecosystem services of wetlands. In addition to increasing agronomic yield, the proposed modus operandi can also improve the livelihood security of farmers through an additional income streams by: (i) trading of SOC credits generated through adoption of conservation agriculture in littoral zones, and (ii) promoting fish and duckery culture in conjunction with deepwater rice farming. Furthermore, the proposed strategies will also set in motion the process of restoration of wetlands while enhancing C sink capacity of the ecosystems.  相似文献   

11.
In 2011 Indonesia decreed a moratorium on forest licenses over 69 million hectares (Mha) in order to suspend haphazard forest exploitation. However, only ∼12–22 Mha were actually afforded new protection from licensing. Herein I observe a further 5.5 Mha of moratorium area overlapping forest licenses and therefore subject to excisement from the moratorium. These 5.5 Mha, like the 4.5 Mha excised from the moratorium to date, are not readily explicable outside of small government committees. This highlights the quasi-transparency of the mapping process: the moratorium map is widely disseminated, yet its base data and decisions made on their basis are guarded. Implementing ministries seek to comply with reforms while simultaneously protecting their administrations from upset – an ultimately compromised position with tangible implications. This has undermined acceptance by the inherently sceptical Indonesian conservation community; yet its highly critical ‘watch dog’ role has ironically contributed by heightening government wariness. The way out of this dynamic is for the ministries to render all data public and, critically, be prepared to weather the inevitable wave of data-fuelled attack for the public good.  相似文献   

12.
In this study, an interval fuzzy chance-constrained land-use allocation (IFCC-LUA) model is developed for sustainable urban land-use planning management and land use policy analysis under uncertainty. This method is based on an integration of interval parameter programming (IPP), fuzzy flexible linear programming (FFLP) and chance-constrained programming (CCP) techniques. Complexities in land-use planning management system can be systematically reflected, thus applicability of the modeling process can be highly enhanced. The developed method is applied to planning land-use allocation practice in Nanjing city, China. The objective of the IFCC-LUA is maximizing net benefit from LUA system and the main constraints include investment constraints, land suitability constraints, water/power consumption constraints and wastewater/solid waste capacity constraints. Modeling results indicate that desired system benefit will be between [1.34, 1.74] × 1012 yuan under the minimum violating probabilities; the optimized areas of commercial land, industrial land, agricultural land, transportation land, residential land, water land, green land, landfill land and unused land will be [290, 393] hm2, [176, 238] hm2, [3245, 4390] hm2, [126, 170] hm2, [49, 66] hm2, [1241, 1679] hm2, [102, 138] hm2, [7, 10] hm2 and [178, 241] hm2. They can be used for generating decision alternatives and thus help decision makers identify desired land use policies under various system-reliability constraints of economic development requirement and environmental capacity of pollutant. Tradeoffs between system benefits and constraint violation risks can also be tackled.  相似文献   

13.
Mexico is a megadiverse country with large agroclimatic diversity and socioeconomic inequality. These two factors result in strong diversity in diets and agricultural systems within the country. In this paper, we assess the impact of Mexican diets and production systems on the per capita land requirements for food. We estimate it for the extremes: from the very basic diet of the poorest share of the population to the affluent diet of the richest share of the population; and for extensive and intensive systems, with irrigation as the indicator of the intensity of the system. We show that the basic diet produced in rainfed systems requires 1620 m2/cap/yr and produced in irrigate systems requires 700 m2/cap/yr. The affluent diet produced in rainfed systems requires 2540 m2/cap/yr and produced in irrigated systems requires 1230 m2/cap/yr. Hence, differences in diets result in a requirement for 80% or 60% more land for an affluent diet; and differences in production systems result in more than twice the amount of land for extensive than for intensive systems. In 2050, it would be possible to feed the entire population with affluent diets only if all the present area of crop land had the productivity of intensive systems. In contrast, it would be possible to feed all people with a basic diet even if all present crop land area had only the productivity of extensive systems.  相似文献   

14.
An efficiency analysis revealed the relative magnitude of wood traits that distinguishes efficient radiata pine logs to produce New Zealand structural grades. Technical and cost efficiencies were obtained by using data envelopment analysis (DEA). Wood trait prices used to perform the cost efficiency corresponded to economic weights derived from a partial regression. These values were 1.1, 29.7, 0.3 and ?0.4 NZ $/m3 for small end diameter (cm), stiffness (GPa), basic density (kg/m3) and largest branch (mm) respectively. The most efficient logs were those with the highest difference between recovery value and price. There were positive and significant correlations between technical efficiency and wood stiffness (0.46, p < 0.05) and between cost efficiency and log recovery value (0.85, p < 0.05). The most efficient logs had a ratio of 1:4 between stiffness and small end diameter whereas logs that did not generate structural lumber presented ratios close to 1:8. This information will inform the development of breeding objectives, and help segregating and pricing logs by using traits patterns that result in efficient logs for the production of structural wood.  相似文献   

15.
The management of forests to store carbon and mitigate climate change has received significant international attention during the last decade. Using in situ data from a 2008–2009 forest inventory field campaign in Sri Lanka, this study describes the structural characteristics and carbon stocks of six natural forest types. This paper has a dual scope: i) to highlight the variation in carbon stored in aboveground biomass within and between forest types and ii) to determine the implications of the allometric equations chosen to calculate biomass carbon stocks. This study concerns work related to climate change interventions, such as Reducing Emissions from Deforestation and Forest Degradation (REDD+) and other forest-related, performance-based initiatives that require proper monitoring, reporting, and verification of carbon stocks, sinks and emissions. The results revealed that forests are heterogeneous in terms of tree density and height–diameter relationships, both between and within the six forest types investigated. The mean aboveground carbon stock in the different forest types ranged from 22 to 181 Mg C ha−1, and there were statistically significant differences in the carbon stocks of the six forest types in 7 of 15 cases. The estimated carbon stock depended heavily on the allometric equation used for the calculations, the variables, and its application to the specific life zone. Due to the diversity of forest structures, these results suggest that caution should be taken when applying default values to estimate forest carbon stocks and emission values in reporting and accounting schemes. The results also indicated the need for allometric equations that are context-specific for different forest types. Therefore, new field investigations and measurements are needed to determine these specific allometric equations, as well as the potential variation in forest carbon stocks in tropical natural forests.  相似文献   

16.
Scenarios of future outcomes often provide context for policy decisions and can be a form of science communication, translating complex and uncertain relationships into stories for a broader audience. We conducted a survey experiment (n = 270) to test the effects of reading land use change scenarios on willingness to participate in land use planning activities. In the experiment, we tested three combinations of scenarios across two time periods, comparing survey responses of individuals reading a set of scenarios with individuals who did not read scenarios. Reading scenario narratives increased willingness to participate in land use planning activities and perceived self-efficacy. Measures of interest and sense of community also increased willingness to participate. Tests of an indirect mediation model found self-efficacy partially mediated the effect of reading scenarios on willingness to participate. This latter relationship may be a mechanistic explanation for the effect of reading scenarios. Envisioning the future with brief, bulleted scenarios of land use change in a print format appears to increase self-efficacy in planning for the future. Our results suggest scenarios can serve as a vehicle for changing public participation in land use planning.  相似文献   

17.
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   

18.
Forests and woodlands dominated by tree species of the genus Melaleuca cover around 7,556,000 ha in Australia and predominantly occur as wetland ecosystems. In this Viewpoint, we use published secondary data to estimate that there is likely to be between 158 tC/ha and 286 tC/ha stored in Melaleuca forests. These estimates are at least five times greater than the previous estimate made by the Australian Government (about 27.8 tC/ha). There are 2.1 million ha of protected Melaleuca forest which likely stock between 328 M tC and 601 M tC; equivalent to between 2.7% and 5.0% of total carbon storage of all Australian native forests. These estimates are significant because it appears that carbon stocks in Melaleuca forests are currently dramatically under-estimated in Australia's national greenhouse gas emissions inventory reported under the United Nations Framework Convention on Climate Change (UNFCCC). Whilst the precision of the estimates is limited by the availability of rigorous primary data, we also argue that the estimates are indicative and meaningful, and this synopsis highlights the fact that this forest type should be considered a significant carbon store nationally and globally.  相似文献   

19.
The assessment of agriculture at a regional scale is necessary to better guide regional agricultural planning. To improve the contribution of agriculture to sustainable regional development, assessments must take account of the locations and diversity of cropping systems. We have therefore developed a method based on a set of multi-scale indicators to assess the contribution of agriculture to the sustainable development of regions, and its evolution over time. This method can identify: i) sustainability issues, ii) relevant indicators that will provide information on impacts at the field scale, iii) a method to aggregate indicators, iv) data on cropping systems, and v) a database containing spatial units to analyse the whole region. Application of this method to Guadeloupe (2004–2010) enabled the definition of ten issues and 16 indicators, with three procedures to aggregate information from 36 cropping systems allocated to 11,908 fields between 2004 and 2010. Economic, social and environmental sustainability was poor in 2004, with high dependency on subsidies (47.3 M€ yr−1), low agricultural added value (48.5 M€ yr−1), low employment (only 1799 workers), significant risks of crop contamination and pressure on water quality. The total value of subsidies and the risks of river pollution tended to decrease between 2004 and 2010 because of a reduction in intensive banana cropping systems. In parallel, we were able to see that sugar cane, the most widespread crop in Guadeloupe, made only a small contribution to employment and food self-sufficiency during the studied period. The spatial representation revealed that improvements have been seen in southern Guadeloupe due to reductions in banana cultivation. This method was therefore helpful in identifying the most critical agricultural development issues and helping to highlight areas where relevant agricultural land use policies could be formulated.  相似文献   

20.
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   

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