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1.
An agent-based model is developed to explore the pattern of fuelwood collection in an 1178 ha forest area in rural mountainous Nepal. The model relates fuelwood collection intensity and amount of dead wood available for collection to the diversity of polypore species, a group of strictly dead wood dependent fungi which can be used as indicators of the biodiversity associated with dead wood. By analysing scenarios of increased collection the model shows that the relative impact on polypore diversity is rising more rapidly than the time used for collection. This indicates that better market access in the future could potentially imply a major threat to biodiversity associated with dead wood.  相似文献   

2.
Fuelwood is the primary energy for most households throughout the developing world. With increasing urbanization and declining local availability of fuelwood, a growing proportion of households obtain their fuelwood by purchasing it. These fuelwood markets are the key nexus in supply and demand scenarios and can be potentially significant points for intervention to address energy security amongst the urban poor. This paper reports on the fuelwood demand and marketing in a small town in South Africa. Despite the availability of more modern fuels and state subsidization of electricity, fuelwood was still used by half the households. Annual demand was 1.2 t per household. Over half of the households bought their fuelwood requirements because local stocks were limited. Those households that did collect their own fuelwood were significantly poorer than households that purchased fuelwood, as well as households that did not use fuelwood at all. Fuelwood markets operated through 45-60 vendors who transported fuelwood from further afield. Income from the fuelwood trade was low, but was strongly linked to hours worked. Thus, vendors working a full week did earn a meaningful income, especially in the context of high unemployment in the area. Fuelwood vendors also provided casual employment opportunities for unskilled labour. Most vendors harvested fuelwood from commonage lands, with most of the wood being from alien species. Local stocks of wood are declining in the face of constant transformation of commonage to residential areas, and a national water and biodiversity conservation programme to eradicate alien plants. This decline poses a threat to the financial viability of fuelwood markets. Yet, an opportunity exists to incorporate the vendors into the alien plant clearing programme, since they already perform such a function.  相似文献   

3.
Models have shown that levels of law enforcement in Luangwa Valley, Zambia, during the 1980s were not adequate to prevent illegal exploitation of black rhinos and African elephants. Theory suggests that the deterrent effect of an increase in detection rate will be larger than that of a similar increase in penalty. The most effective penalty, in economic terms, would be a variable fine related to the number of illegal trophies harvested, but this may be hard to legislate effectively. Wildlife managers conserving rhinos and elephants should focus on improving detection rates rather than on requesting severe penalties with no improvements in detection.  相似文献   

4.
We conduct a field experiment to examine whether the deterrent effect of law enforcement depends on the salience of law enforcement activity. Our focus is on illegal disposal of household garbage in residential areas. At a random subset of 56 locations in a mid-sized city, law enforcement officers supplemented their regular enforcement activities by the practice of putting brightly-colored warning labels on illegally disposed garbage bags. This treatment made the existing enforcement activities suddenly much more apparent to residents. We find evidence for a substantial reduction in illegal disposal of garbage in response to the treatment.  相似文献   

5.
Management activities such as law enforcement and community outreach are thought to affect conservation outcomes in protected areas, but their importance relative to intrinsic environmental characteristics of the parks and extrinsic human pressures surrounding the parks have not been explored. Furthermore, it is not clear which is more related to conservation outcomes—the management itself or local people's perceptions of the management. We measured objective (reports by park staff) and subjective (reports by local people) levels of community outreach and law enforcement based on responses to 374 questionnaires. We estimated mammal abundance and diversity of 6 protected areas based on data from 115 camera traps in Xishuangbanna, southwest China, a biodiversity hotspot with high hunting and land-conversion pressures. We then examined correlations among them and found that local people's perception of law enforcement was positively related to the local abundance of 2 large, hunted species, wild boar (Sus scrofa) (β = 15.22) and muntjac (Muntiacus vaginalis) (β = 14.82), but not related to the abundance of smaller mammals or to objective levels of enforcement. The subjective frequency of outreach by park staff to local communities (β = 3.42) and park size (β = 3.28) were significantly and positively related to mammal species richness, whereas elevation, human population density, and subjective frequency of law enforcement were not. We could not conclude that community outreach and law enforcement were directly causing increased mammal abundance and diversity. Nevertheless, the patterns we detected are some of the first empirical evidence consistent with the idea that biodiversity in protected areas may be more positively and strongly related to local perceptions of the intensity of park management than to either intrinsic (e.g., elevation, park size) or extrinsic (e.g., human population density) environmental factors.  相似文献   

6.
Abstract: Primates are regularly hunted for bushmeat in tropical forests, and systematic ecological monitoring can help determine the effect hunting has on these and other hunted species. Monitoring can also be used to inform law enforcement and managers of where hunting is concentrated. We evaluated the effects of law enforcement informed by monitoring data on density and spatial distribution of 8 monkey species in Taï National Park, Côte d’Ivoire. We conducted intensive surveys of monkeys and looked for signs of human activity throughout the park. We also gathered information on the activities of law‐enforcement personnel related to hunting and evaluated the relative effects of hunting, forest cover and proximity to rivers, and conservation effort on primate distribution and density. The effects of hunting on monkeys varied among species. Red colobus monkeys (Procolobus badius) were most affected and Campbell's monkeys (Cercopithecus campbelli) were least affected by hunting. Density of monkeys irrespective of species was up to 100 times higher near a research station and tourism site in the southwestern section of the park, where there is little hunting, than in the southeastern part of the park. The results of our monitoring guided law‐enforcement patrols toward zones with the most hunting activity. Such systematic coordination of ecological monitoring and law enforcement may be applicable at other sites.  相似文献   

7.
Influenced by models of optimal law enforcement, several authors have recently revised the work on efficient levels of regulatory control to accommodate the realities of underenforcement and imperfect compliance. However, most of these efforts have centered on either the enforcement agency or the firm and have largely ignored the decentralized nature of the enforcement process. This paper extends these results by modelling both the firm and the local agency and by incorporating detection uncertainty and concealment activity. Each model is then evaluated with respect to the alternative regulatory regimes of direct controls and emission taxes.  相似文献   

8.
日本、韩国的土壤污染防治法及其对我国的借鉴   总被引:1,自引:0,他引:1  
在东亚地区,日本、韩国的土壤污染防治立法最为活跃,先后制定了专门的土壤污染防治法及其配套法规.本文从立法背景、立法模式、主要内容及制度设置、土壤污染防治的管理体制等方面,对日本、韩国的土壤污染防治立法进行了比较分析.这些立法实践及其施行经验,对我国正在进行的土壤污染防治立法有实际借鉴意义.  相似文献   

9.
This paper examines how enforcement affects the structure and performance of emissions trading programs with price controls under uncertainty about firms' abatement costs. The analysis highlights how an enforcement strategy can cause abatement-cost risk to be transmitted to enforcement costs via the price of permits. When this occurs, accommodating the effect of abatement-cost risk with an optimal policy results in higher expected emissions and lower expected permit price than their second-best optimal values. However, it is possible to design an enforcement strategy that shields enforcement costs from abatement-cost risk by tying sanctions directly to permit prices. This enforcement strategy stabilizes enforcement effort, the optimal permit supply and price controls are independent of enforcement costs, and the policy produces the second-best optimal outcome.  相似文献   

10.
ABSTRACT

Post-frontier governance in the Brazilian Amazon highlights the interaction of regulatory technologies, institutions and practices to combat illegal deforestation and appropriation of public lands. While the Amazon fires received tremendous media coverage in 2019, the dismantlement of environmental laws and regulatory agencies has supported the rise in deforestation as early as 2012. We discuss the impact of post-frontier governance in Southwest-Pará by analyzing the spatial distribution of deforestation, territorial management, law enforcement, and environmental regularization from 2000 to 2018. The integration of spatial analysis with qualitative field surveys in the blacklisted municipality Novo Progresso shows that deforestation control largely fails, specifically in undesignated public lands. While land tenure security remains the biggest challenge in the region, the persistent imagination of free-for-all frontier spaces encourages the uncontrolled appropriation of and speculation with public lands. Here, the Rural Environmental Registry (CAR) has been identified as a key instrument to secure land claims.  相似文献   

11.
The government of Indonesia, which presides over 10% of the world's tropical forests, has set ambitious targets to cut its high deforestation rates through an REDD+ scheme (Reducing Emissions from Deforestation and forest Degradation). This will require strong law enforcement to succeed. Yet, strategies that have accomplished this are rare and, along with past failures, tend not to be documented. We evaluated a multistakeholder approach that seeks to tackle illegal logging in the carbon‐rich province of Aceh, Sumatra. From 2008 to 2009, Fauna & Flora International established and supported a community‐based informant network for the 738,000 ha Ulu Masen ecosystem. The network reported 190 forest offenses to local law enforcement agencies, which responded with 86 field operations that confiscated illicit vehicles, equipment, and timber, and arrested 138 illegal logging suspects. From 45 cases subsequently monitored, 64.4% proceeded to court, from which 90.0% of defendants received a prison sentence or a verbal warning for a first offense. Spatial analyses of illegal logging and timber storage incidents predicted that illegal activities would be more effectively deterred by law enforcement operations that targeted the storage sites. Although numerous clusters of incidents were identified, they were still widespread reflecting the ubiquity of illegal activities. The multistakeholder results were promising, but illegal logging still persisted at apparently similar levels at the project's end, indicating that efforts need to be further strengthened. Nevertheless, several actions contributed to the law enforcement achievements: strong political will; strong stakeholder support; and funding that could be promptly accessed. These factors are highlighted as prerequisites for achieving Indonesia's ambitious REDD+ goals. Rompiendo el Círculo Vicioso de la Tala Ilegal en Indonesia  相似文献   

12.
An experimental analysis of compliance in dynamic emissions markets   总被引:1,自引:0,他引:1  
Two important design elements for emission trading programs are whether and to what extent firms are able to bank emissions permits, and how these programs are to be enforced. In this paper we present results from laboratory emissions markets designed to investigate enforcement and compliance when these markets allow permit banking. Banking is motivated by a decrease in the aggregate permit supply in the middle of multi-period trading sessions. Consistent with theoretical insights, our experiments suggest that high permit violation penalties have little deterrence value in dynamic emissions markets, and that the main challenge of enforcing these programs is to motivate truthful self-reports of emissions.  相似文献   

13.
Two important design elements for emission trading programs are whether and to what extent firms are able to bank emissions permits, and how these programs are to be enforced. In this paper we present results from laboratory emissions markets designed to investigate enforcement and compliance when these markets allow permit banking. Banking is motivated by a decrease in the aggregate permit supply in the middle of multi-period trading sessions. Consistent with theoretical insights, our experiments suggest that high permit violation penalties have little deterrence value in dynamic emissions markets, and that the main challenge of enforcing these programs is to motivate truthful self-reports of emissions.  相似文献   

14.
Guoliang Liu  Shijie Han 《Ecological modelling》2009,220(13-14):1719-1723
In their efforts to deal with global climate change, scientists and governments have given much attention to the carbon emissions associated with fossil fuels and to strategies for reducing their use. While it is very important to burn less fossil fuel and to employ alternative energy sources, other carbon-reduction options must also be considered. Given that forests comprise a large portion of the global landbase and that they play a very significant role in the global carbon cycle, it is logical to examine how forest management practices could effect reductions in carbon emissions. Many papers that discuss forest carbon sinks or sources refer only to the short term (<20 years). This paper focuses on the sustainable carbon storage contributions of a forest over the long term. This paper explains that long-term carbon storage and reduced carbon fluctuation can be achieved by a combination of improved forest management and efficient transfer of carbon into wood products. Here we show how three different forest management scenarios affect the overall carbon storage capacity of forest and wood products combined over the long term. We used a timber supply model and scenario analysis to predict forest carbon and other resource conditions over time in the Prince George Forest District, a 3.4-million-ha landbase in northern British Columbia. We found that the high-harvest scenario stores 3% more carbon than the low-harvest scenario and 27% (120 million tonnes) more carbon than the no-harvest scenario even though only 1.2-million ha is in timber harvesting landbase. Our results tell us that forest management practices that maintain and increase forest area, reduce natural disturbances in the forest, improve forest conditions, and ensure the appropriate and timely transfer of carbon into wood products lead to increasing overall carbon storage, thereby reducing carbon in the atmosphere.  相似文献   

15.
ABSTRACT

This case study was conducted in Himalayan watershed to understand traditional farming and socio-economic status of the people in Kumaon Himalaya, Uttarakhand, India. In spite of high literacy rate in this area, their livelihood security is reliant on traditional farming practices that include agroforestry beside forest produce. More than 85% farming is rainfed and managed in a traditional way. Land holding size owned by farmers in the area extended from 0.57 to 2.57 ha but majority of farmers (51–80%) had farms of size less than 0.50 ha. The study revealed that forests provided 73–79% of required energy from fuelwood and more than 81% fodder. Agroforestry, livestock (dairy and poultry/goat rearing) and labour employment are the major sources of income to the people in the watershed. The income of people was positively correlated with livestock rearing and traditional farming.  相似文献   

16.
ABSTRACT

In this study, we present a critical account of the enforcement of the Forest Law in the Province of Salta, Argentina. We discuss whether the objectives of this law were accomplished and we analyze the role that some technical tools, coupled with specific theoretical approaches, could play in its future enforcement. We illustrate our analysis with data from a case study in the Chaco region of this Province. We identified, mapped and analyzed land claims by indigenous communities and small-scale agricultural producers, and large-scale land acquisitions, and we discuss how these two variables could be used to improve the technical accuracy and the social legitimacy of the zoning map required by the Forest Law. We conclude that a balanced combination of land-change science methods and political ecology can be useful to improve the fairness of decision-making processes and the sustainability of social-environmental governance in agricultural frontiers.  相似文献   

17.
Biocides are active substances and products which are intended to destroy (…) any harmful organism by chemical or biological means. Typical applications are for instance wood preservatives, antifouling products or disinfectants. In the European Union the use of biocidal products is regulated since 1998 by the Biocidal Product Directive 98/8/EG (BPD). The BPD was transposed into German law in 2001 by the “Biozid-Gesetz”. The Federal Environment Agency is responsible for the environmental risk assessment of biocidal active substances and products under the “Biozid-Gesetz” in Germany. The European Commission has to evaluate the BPD seven years after endorsement and if necessary, has to submit a proposal for the revision of the directive. It is expected that the European Commission will publish soon a review of the enforcement of the BPD together with suggestions for the revision of the directive. In this article the German Federal Environment Agency summarises suggestions for the revision of the BPD based on its ten years experience with the directive: The scope of the BPD needs an exact clarification of borderlines in order to avoid confusion with other legislation. Food and feeding stuff together with natural products like lavender branches and cedar wood, which are used as attracting or repellent agents, have to be excluded from the scope of the BPD. Special data requirements for natural oils and pheromones should be developed to take the complex composition of these substances into account. The advantages of a centralised and decentralised authorisation procedure are discussed for biocidal products in special product types. Furthermore we stipulate that biocidal active substances which are nano particles are treated as separate active substances with own identities. Due to animal welfare reasons it should be obligatory to share data from vertebrate animal studies as it is already mandatory under the REACH regulation. The import of articles treated with biocidal active substances into the European market should only be allowed, if the active substance is approved for their biocidal use within the EU. Finally we suggest to implement an obligation to report the market shares or consumption rates of biocidal active substances and products. Together with procedural simplifications and adaptation in the scope of the directive, changes of the data requirements will be the key issues during the revision of the BPD. Most important, these changes should not reduce but ideally increase the level of protection for human health and the environment.  相似文献   

18.
Background, aim and scope The increasing use of wood for generating heat and electricity requires that more and more fuels be obtained directly or indirectly from the forest. Sound, sustainable recycling management calls for the return of any generated wood ash back to the forest to make use of the nutrients it contains. Similarly, recycling this ash in other locations such as agricultural land or private gardens can serve equally well as fertilizer. At the same time, it is critical that no accumulated pollutants be introduced into the nutrient loop. Wood ash that is heavily laden with such pollutants must not be considered for recycling. As part of this research project, commissioned by the Ministry for the Environment and Conservation, Agriculture and Consumer Protection of the State of North Rhine-Westphalia in Germany (MUNLV), ash samples of 209 wood-fired appliances generating between 10 and 4000?kW of heat performance were taken from throughout the federal state of North Rhine-Westphalia. Untreated wood, either forested or scrap, was used as the sole fuel for these appliances. Materials and methods All course ash and fly ash samples were analyzed to determine their composition of main nutrients, heavy metals, and the elements Fe, Cl, Si, Al and Na. The purpose of this analysis was to evaluate the suitability of this wood ash for reintroduction to forest soils or as fertilizer in other types of soil. Results The majority of the wood ash samples in this study contained sufficiently high amounts of nutrients to match the requirement for stand-alone fertilizers (PK-fertilizer, potash fertilizer). However, the heavy metal content was highly variable, with a mean content high enough to prohibit them from being classified per se as PK- or potash fertilizer for agricultural land. Due to the high quantities of cadmium, application of this ash to garden soils would likewise be ill-advised. Discussion On forest soils German law permits application of a mixture of potash fertilizer containing, at most, 30?% wood ash (course ash). Because of the high amounts of cadmium and copper, wood ash from our samples can only comprise a maximum of 28?% when added to typically used potash fertilizers. Higher percentage of wood ash would exceed the cut-off value established by the German Fertilizer Ordinance (Düngemittelverordnung – DüMV). Conclusions The application of wood ash on agricultural land and in private gardens is, rightfully so, highly regulated by law. However, the rules governing application of wood ash in the forest are much more lax. Determination of heavy metal content in wood ash cannot be used to determine compliance with DüMV standards because of the high content and fluctuating nature of heavy metals found. Recommendations and perspectives Presently an alternative approach for classifying the ecologic risk of wood ash recycling is being developed.  相似文献   

19.
A simple fishery model is developed with legal and illegal markets for fish, the latter market being combated by enforcement efforts put forth by a social regulator. In response to enforcement, violators undertake avoidance activities to escape detection. The possible impacts of illegal activity on optimal fishery management are then explored, and some policy implications are suggested. Concurrently, optimal regulation is calculated when: (a) only legal surplus is maximized versus (b) when both legal and illegal surplus is maximized. The rationale for these two regimes and their divergence in optimal management policies is outlined.  相似文献   

20.
As a result of forcing the energy utilization from biomass, the amounts of combustion residues, especially woodash, are growing. For a sustainable and ecologically effective closed-cycle economy, the knowledge of the chemical composition of the ashes is necessary. The matrix wood ash is very complex, due to the great number of constituents in different concentrations. Therefore it is important to develop a combination of analytical methods for the complete detection of nutrients and heavy metals in wood ash. Ashes from different heating plants (wood chips-, bark-and sawdust combustion systems) were analysed with X-ray methods as well as with acid-digestion in combination with atomic spectrometry detection. The results were compared and checked for their plausibility by statistical methods and material balances for the inorganic elements from the biomass to the ash fractions. As a result of this evaluation astandard method is recommended for the analysis of wood ash. This method consists of a combination of dry (X-ray) analysis (for the elements Si, Ca, Mg, K, P, Al, Fe, Mn) and fluid analysis (for the detection of heavy metals).  相似文献   

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