An Economic Assessment of Wildlife Farming and Conservation

Abstract:  The supply-side approach to conservation, as recommended by economists, prescribes the provision of cheap substitutes for wildlife commodities in an effort to lower the price of such commodities and reduce harvesting pressure. We developed a theoretical economic model to examine whether wildlife farming or ranching indeed contributes to conservation. We first present the naïve economic model that lends support to the supply-side approach. This model is incomplete because it fails to capture the fact that most wildlife markets are not perfectly competitive (instead, models are characterized by a small number of suppliers who have a certain degree of market power), which also implies that it fails to incorporate strategic interaction between suppliers. We then present an alternative model of the (illegal) wildlife trade that reflects imperfect competition and strategic interaction, and demonstrate that wildlife farming may stimulate harvesting (or poaching) rather than discourage it. By applying the model to the case of rhinoceros poaching and ranching, we demonstrate the potentially ambiguous outcomes of rhinoceros-ranching initiatives—wild rhinoceros stocks may recover or suffer from additional depletion, depending on key parameters and the type of competition on output markets. We also show that this type of ambiguity may be eliminated when policy makers restrict quantities of farmed output through a quota system; in that case, introducing wildlife farming will unambiguously promote conservation. In the absence of such accompanying regulation, however, policy makers should be careful when stimulating wildlife farming and be aware of potentially adverse consequences.     

Advantages and disadvantages of the use of irradiation for food preservation

Food irradiation is a physical method of processing food (e.g. freezing, canning). It has been thoroughly researched over the last four decades and is recognized as a safe and wholesome method. It has the potential both of disinfesting dried food to reduce storage losses and disinfesting fruits and vegetables to meet quarantine requirements for export trade. Low doses of irradiation inhibit spoilage losses due to sprouting of root and tuber crops. Food- borne diseases due to contamination by pathogenic microorganisms and parasites of meat, poultry, fish, fishery products and spices are on the increase. Irradiation of these solid foods can decontaminate them of pathogenic organisms and thus provide safe food to the consumer. Irradiation can successfully replace the fumigation treatment of cocoa beans and coffee beans and disinfest dried fish, dates, dried fruits, etc. One of the most important advantages of food irradiation processing is that it is a coldprocess which does not significantly alter physico-chemical characters of the treated product. It can be applied to food after its final packaging. Similar to other physical processes of food processing, (e.g. canning, freezing), irradiation is a capital intensive process. Thus, adequate product volume must be made available in order to maximize the use of the facility and minimize the unit cost of treatment. Lack of harmonization of regulations among the countries which have approved irradiated foods hampers the introduction of this technique for international trade. Action at the international level has to be taken in order to remedy this situation. One of the important limitations of food irradiation processing is its slow acceptance by consumers, due inter alia to a perceived association with radioactivity. The food industry tends to be reluctant to use the technology in view of uncertainties regarding consumer acceptance of treated foods. Several market testing and consumer acceptance studies have been carried out on food irradiation in recent years. These studies showed that, if the safety and the benefits of food irradiation were properly explained, the consumers were willing to accept irradiated foods. Considering its potential role in the reduction of post-harvest losses, providing safe supply of food and overcoming quarantine barriers, food irradiation has received wider government approvals during the last decade. There is also a trend towards increased commercialization of irradiated food. Currently, there are 47 irradiation facilities in some 23 countries being used for treating foods for commercial purposes.     

冶金行业安全管理模式探讨

从全国大钢安全协作会的成立、停顿、恢复、发展的历程，探讨了在市场经济体制下，在行业主管部门缺失的情况下，行业安全管理的新模式。     

对外经济贸易对中国碳排放的影响:基于省级面板数据的实证分析

改革开放以来,我国的对外经济贸易有了显著的发展,外商直接投资和进出口的快速增长有效地推动了经济的快速发展。然而在经济发展的同时,我国碳排放水平日益提高,已成为全球最大排放国。为了更好地管控碳排放,研究外商直接投资(FDI),对外贸易与碳排放的关系具有重要意义。本文通过对我国1995—2011年29个省(市、自治区)的FDI、对外贸易对碳排放的动态效应分析发现,FDI与进出口水平的提升均有利于降低我国碳排放的水平,“污染天堂”假说在我国并未得到证实。同时,本文验证了“环境库兹涅茨曲线”在我国的存在,证实了我国的碳排放水平与人均GDP存在倒“U”型关系。     

Endogenous growth,asymmetric trade and resource dependence

The aggregate income of oil-exporting countries relative to that of oil-poor countries has been remarkably constant in recent decades, despite the existence of structural gaps in productivity growth rates. This stylized fact is rationalized in an endogenous growth model of asymmetric trade where resource-poor and resource-rich economies display productivity differences but stable income shares due to terms-of-trade dynamics. The model yields two testable predictions that deserve empirical scrutiny: (i) the asymmetric impact, between exporters and importers, of national taxes on resource use on income shares and (ii) the inverse relation between terms-of-trade dynamics and total factor productivity growth.     

Bayesian Decision‐Network Modeling of Multiple Stakeholders for Reef Ecosystem Restoration in the Coral Triangle

Proposals for marine conservation measures have proliferated in the last 2 decades due to increased reports of fishery declines and interest in conservation. Fishers and fisheries managers have often disagreed strongly when discussing controls on fisheries. In such situations, ecosystem‐based models and fisheries‐stock assessment models can help resolve disagreements by highlighting the trade‐offs that would be made under alternative management scenarios. We extended the analytical framework for modeling such trade‐offs by including additional stakeholders whose livelihoods and the value they place on conservation depend on the condition of the marine ecosystem. To do so, we used Bayesian decision‐network models (BDNs) in a case study of an Indonesian coral reef fishery. Our model included interests of the fishers and fishery managers; individuals in the tourism industry; conservation interests of the state, nongovernmental organizations, and the local public; and uncertainties in ecosystem status, projections of fisheries revenues, tourism growth, and levels of interest in conservation. We calculated the total utility (i.e., value) of a range of restoration scenarios. Restricting net fisheries and live‐fish fisheries appeared to be the best compromise solutions under several combinations of settings of modeled variables. Results of our case study highlight the implications of alternate formulations for coral reef stakeholder utility functions and discount rates for the calculation of the net benefits of alternative fisheries management options. This case study may also serve as a useful example for other decision analyses with multiple stakeholders. Modelo de Red de Decisión Bayesiana de Múltiples Actores Interesados en la Restauración de Ecosistemas de Arrecife en el Triángulo de Coral     

Spatial econometric model of natural disaster impacts on human migration in vulnerable regions of Mexico

Mexico's vast human and environmental diversity offers an initial framework for comprehending some of the prevailing great disparities between rich and poor. Its socio-economic constructed vulnerability to climatic events serves to expand this understanding. Based on a spatial econometric model, this paper tests the contribution of natural disasters to stimulating the emigration process in vulnerable regions of Mexico. Besides coping and adaptive capacity, it assesses the effects of economic losses due to disasters as well as the adverse production and trade conditions of the 1990s on emigration rates in 2000 at the municipality level. Weather-related disasters were responsible for approximately 80 per cent of economic losses in Mexico between 1980 and 2005, mostly in the agricultural sector, which continues to dominate many parts of the country. It is dramatic that this sector generates around only four per cent of gross domestic product but provides a livelihood to about one-quarter of the national population. It is no wonder, therefore, that most emigration from this country arises in vulnerable rural areas.     

The origin of speciation: trace metal kinetics over natural water/sediment interfaces and the consequences for bioaccumulation

The speciation of heavy metals was measured over a variety of natural and undisturbed water/sediment interfaces. Simultaneously, two benthic species (oligochaete Limnodrilus spp. and the midge Chironomus riparius) were exposed to these sediments. Under occurring redox conditions, free ion activities of trace metals Cd, Cu, Ni, Pb, and Zn were measured with a chelating exchange technique, while geochemical conditions (i.e., redox) remained in tact. Free ion activities were compared with total dissolved concentrations in pore waters and surface waters in order to relate speciation to bioaccumulation. Limnodrilus spp. and C. riparius have accumulation patterns that could be linked to time-dependent exposure concentrations, expressed as chemical speciation, in the surface water and the sediment's pore water. Concentrations of free metal ions in the overlying surface water, rather than in sediment pore water, proved to be the best predictor for uptake. For the first time, measurements are obtained from sediments without disturbing physical-chemical conditions and thus bioavailability, a major restriction of other studies so far.     

Observation and origin of organochlorine compounds and polycyclic aromatic hydrocarbons in the free troposphere over central Europe

On Zugspitze (2670 m a.s.l.), Alps, higher concentrations were observed during a winter than during a summer measurement campaign of PAHs, chlorobenzenes (43.6 vs. 2.0 pg m⁻³) and DDTs (3.7 vs. 1.2 pg m⁻³), while hexachlorocyclohexanes and PCBs were found at similar levels. The PCB, HCH and DDT levels are among the lowest ever reported from outside the Arctic. Mostly lower levels were found in samples collected in summer than in winter despite a significant boundary layer air influence, but no such influence on samples collected during the winter campaign. Boundary layer influence was quantified by Lagrangian particle dispersion model retroplume analyses. Photochemical lifetimes corresponding to k_OH < 1.5 × 10⁻¹² cm³ molec⁻¹ s⁻¹ are found for p,p′-DDT, k_OH < 0.75 × 10⁻¹² cm³ molec⁻¹ s⁻¹ for p,p′-DDE and k_OH < 1.0 × 10⁻¹² cm³ molec⁻¹ s⁻¹ for p,p′-DDD.     

浙江省粮食贸易中的虚拟水研究

贸易中的虚拟水研究使人们认识到地区的水资源危机可以通过全球性的经济贸易来缓解。虚拟水的进出口是水资源的一个来源,通过贸易的形式、利用各种外部资源来缓解内部水资源的紧缺,最终解决水资源短缺和粮食安全问题,是社会实现水资源社会化管理、生态环境安全和社会经济可持续发展的战略保障。以浙江省为研究对象,首先利用各类农作物虚拟水含量标准,核算了1997~2006年10 a间浙江省粮食贸易的虚拟水含量。然后比较浙江省全年用水量和用水结构,计算得出粮食贸易产生的年净进口虚拟水量占浙江省年总用水量7.41%左右,占到年农业灌溉用水的1717%。研究结果表明,过去10 a浙江省粮食贸易的虚拟水是浙江省水资源的一个重要的补充。〖