Obstruction of biodiversity conservation by minimum patch size criteria

Minimum patch size criteria for habitat protection reflect the conservation principle that a single large (SL) patch of habitat has higher biodiversity than several small (SS) patches of the same total area (SL > SS). Nonetheless, this principle is often incorrect, and biodiversity conservation requires placing more emphasis on protection of large numbers of small patches (SS > SL). We used a global database reporting the abundances of species across hundreds of patches to assess the SL > SS principle in systems where small patches are much smaller than the typical minimum patch size criteria applied for biodiversity conservation (i.e., ∼85% of patches <100 ha). The 76 metacommunities we examined included 4401 species in 1190 patches. From each metacommunity, we resampled species–area accumulation curves to evaluate how biodiversity responded to habitat existing as a few large patches or as many small patches. Counter to the SL > SS principle and consistent with previous syntheses, species richness accumulated more rapidly when adding several small patches (45.2% SS > SL vs. 19.9% SL > SS) to reach the same cumulative area, even for the very small patches in our data set. Responses of taxa to habitat fragmentation differed, which suggests that when a given total area of habitat is to be protected, overall biodiversity conservation will be most effective if that habitat is composed of as many small patches as possible, plus a few large ones. Because minimum patch size criteria often require larger patches than the small patches we examined, our results suggest that such criteria hinder efforts to protect biodiversity.     

Tying enforcement to prices in emissions markets: An experimental evaluation

We present results from laboratory emissions permit markets designed to investigate the transmission of abatement cost risk to firms' compliance behavior and regulatory enforcement strategies. With a fixed expected marginal penalty, abatement cost shocks produced significant violations and emissions volatility as predicted. Tying the monitoring probability to average permit prices effectively eliminated noncompliance, but transmitted abatement cost risk to monitoring effort. Tying the penalty to average prices reduced violations, but did not eliminate them. Some individuals in these treatments sold permits at low prices, presumably in an attempt to weaken enforcement. While tying sanctions directly to prevailing permit prices has theoretical and practical advantages over tying monitoring to prices, our results suggest that tying sanctions to prices may not be as effective as predicted without additional modifications.     

Emissions standards and ambient environmental quality standards with stochastic environmental services

Many important environmental policies involve some combination of emission controls and ambient environmental quality standards, for instance SO₂ emissions are capped under Title IV of the U.S. Clean Air Act Amendments while ambient SO₂ concentrations are limited under National Ambient Air Quality Standards (NAAQS). This paper examines the relative performance of emissions standards and ambient standards when the natural environment provides stochastic environmental services for assimilating pollution. For receiving media characterized by greater dispersion in the distribution of environmental services, the optimal emissions policy becomes more stringent, whereas the optimal ambient policy generally becomes more lax. In terms of economic performance, emissions policies are superior to ambient policies for relatively non-toxic pollutants, whereas ambient standards welfare dominate emissions standards for sufficiently toxic pollutants. In the case of combined policies that jointly implement emissions standards and ambient standards, we show that the optimal level of each standard relaxes relative to its counterpart in a unilateral policy, allowing for greater emissions levels and higher pollution concentrations in the environmental medium.     

Tax versus emissions trading scheme in the long run

In this paper we compare the performance of emission taxes and tradable permits under free market entry when firms face idiosyncratic ex ante cost uncertainty. We show that under auctioned permits insufficient entry occurs, while under a linear emission tax scheme, depending on parameters, market entry can be either excessive or insufficient. Our long-run analysis thus contrasts with Spulber׳s (1985) equivalence result and also modifies Weitzman׳s result in favor of an ETS in that the superiority of a tax over an ETS is not guaranteed, even when the Weitzman condition favors a tax. We also show that an ETS is superior to a tax scheme when the entry cost is low and the magnitude of uncertainty/asymmetric information and the size of the output market are large.     

Urban sprawl into Natura 2000 network over Europe

Urban growth is a major threat to biodiversity conservation at the global scale. Its impacts are expected to be especially detrimental when it sprawls into the landscape and reaches sites of high conservation value due to the species and ecosystems they host, such as protected areas. I analyzed the degree of urbanization (i.e., urban cover and growth rate) from 2006 to 2015 in protected sites in the Natura 2000 network, which, according to the Habitats and Birds Directives, harbor species and habitats of high conservation concern in Europe. I used data on the degree of land imperviousness from COPERNICUS to calculate and compare urban covers and growth rates inside and outside Natura 2000. I also analyzed the relationships of urban cover and growth rates with a set of characteristics of Natura sites. Urban cover inside Natura 2000 was 10 times lower than outside (0.4% vs. 4%) throughout the European Union. However, the rates of urban growth were slightly higher inside than outside Natura 2000 (4.8% vs. 3.9%), which indicates an incipient urban sprawl inside the network. In general, Natura sites affected most by urbanization were those surrounded by densely populated areas (i.e., urban clusters) that had a low number of species or habitats of conservation concern, albeit some member states had high urban cover or growth rate or both in protected sites with a large number of species or habitats of high conservation value. Small Natura sites had more urban cover than large sites, but urban growth rates were highest in large Natura sites. Natura 2000 is protected against urbanization to some extent, but there is room for improvement. Member states must enact stricter legal protection and control law enforcement to halt urban sprawl into protected areas under the greatest pressure from urban sprawl (i.e., close to urban clusters). Such actions are particularly needed in Natura sites with high urban cover and growth rates and areas where urbanization is affecting small Natura sites of high conservation value, which are especially vulnerable and concentrated in the Mediterranean region.     

Policy Integration as a Success Factor for Emissions Trading

Emissions trading will not be able to become the single instrument of a national climate policy because of costs for monitoring of greenhouse gases and transfers of allowances. Thus, it is important to assess optimal ways of integrating emissions trading into national climate policy mixes, thus leading to a more efficient policy, especially by allowing the use of transboundary transactions. The implemented trading systems of the UK and Denmark, the agreed EU one, and the planned ones of Norway are used as case studies. In the UK, the introduction of an energy tax on industry was the catalyst that led to the development of emissions trading, voluntary agreements, and two subsidy programs. However, in Denmark trading was limited in scope and not integrated with the successful emission tax. The EU and Norwegian trading schemes both have a large scope and integrate international transfers; the former is integrated with other instruments to avoid free riding. Policy integration will thus enhance the efficiency improvements that emissions trading can introduce.     

Gaseous emissions from lignosulfonates in dust abatement applications

Concerns over possible gaseous emissions from lignosulfonate dust suppressant agents used on dirt roads prompted an investigation into the possible release of sulfur dioxide and organic vapors. Emissions from eight commercial lignosulfonates products applied to three different soil types were measured in environmental chambers. It was determined that except under extreme soil pH conditions (<1), the release of sulfur dioxide from the application of lignosulfonates to roads is essentially non existent. The odor associated with the application was found to be due to trace amounts of organic compounds mainly of the furfural variety. Levels of odor compounds in these products was significantly lower than the previously reported values for spent sulfite liquors because the majority were removed during processing operations prior to sale.     

Relating disposal-based solid waste reduction rates to recycling rates

Some states measure progress in their waste reduction programs on the basis of recycling rates, while others use disposal-based reduction rates. It is generally recognized that these two measures are conceptually distinct. Nevertheless, when informational surveys of waste reduction activities are compiled, the data are usually combined in a manner that blurs this distinction and complicates the issues involved. In this paper, these two concepts are defined in a precise manner and equations are derived which clearly depict the relationship between recycling rates and disposal-based reduction rates. Information from a national survey and the US Environmental Protection Agency is used to illustrate the concepts which are developed in the paper.     

Applications of Numerical Sediment Quality Targets for Assessing Sediment Quality Conditions in a US Great Lakes Area of Concern

Contaminated sediments are receiving increasing recognition around the world, leading to the development of various sediment quality indicators for assessment, management, remediation, and restoration efforts. Sediment chemistry represents an important indicator of ecosystem health, with the concentrations of contaminants of potential concern (COPCs) providing measurable characteristics for this indicator. The St. Louis River Area of Concern (AOC), located in the western arm of Lake Superior, provides a case study for how numerical sediment quality targets (SQTs) for the protection of sediment-dwelling organisms can be used to support the interpretation of sediment chemistry data. Two types of SQTs have been established for 33 COPCs in the St. Louis River AOC. The Level I SQTs define the concentrations of contaminants below which sediment toxicity is unlikely to occur, whereas the Level II SQTs represent the concentrations that, if exceeded, are likely to be associated with sediment toxicity. The numerical SQTs provide useful tools for making sediment management decisions, especially when considered as part of a weight-of-evidence approach that includes other sediment quality indicators, such as sediment contaminant chemistry and geochemical characteristics, sediment toxicity, and benthic macroinvertebrate community structure. The recommended applications of using the numerical SQTs in the St. Louis River AOC include: designing monitoring programs, interpreting sediment chemistry data, conducting ecological risk assessments, and developing site-specific sediment quality remediation targets for small, simple sites where adverse biological effects are likely. Other jurisdictions may benefit from using these recommended applications in their own sediment quality programs.     

The Relative Importance of Sources of Greenhouse-Gas Emissions: Comparison of Global Through Subnational Perspectives

Increasing atmospheric concentrations of greenhouse gases are widely expected to cause global warming and other climatic changes. It is important to establish priorities for reducing greenhouse-gas emissions, so that resources can be allocated efficiently and effectively. This is a global problem, and it is possible, on a global scale, to identify those activities whose emissions have the greatest potential for enhancing the greenhouse effect. However, perspectives from smaller scales must be appreciated, because it is on scales down to the local level that response measures will be implemented. This paper analyzes the relative importance of emissions from the many individual sources, on scales ranging from global to national to subnational. Individual country perspectives and proposed policy measures and those of subnational political entities exhibit some commonalities but differ among themselves and from a global-scale perspective in detail.