Sunny L. Jardine

Global economic potential for reducing carbon dioxide emissions from mangrove loss

Mangroves are among the most threatened and rapidly disappearing natural environments worldwide. In addition to supporting a wide range of other ecological and economic functions, mangroves store considerable carbon. Here, we consider the global economic potential for protecting mangroves based exclusively on their carbon. We develop unique high-resolution global estimates (5′ grid, about 9 × 9 km) of the projected carbon emissions from mangrove loss and the cost of avoiding the emissions. Using these spatial estimates, we derive global and regional supply curves (marginal cost curves) for avoided emissions. Under a broad range of assumptions, we find that the majority of potential emissions from mangroves could be avoided at less than

Optimal approaches for balancing invasive species eradication and endangered species management

10 per ton of CO2. Given the recent range of market price for carbon offsets and the cost of reducing emissions from other sources, this finding suggests that protecting mangroves for their carbon is an economically viable proposition. Political-economy considerations related to the ability of doing business in developing countries, however, can severely limit the supply of offsets and increases their price per ton. We also find that although a carbon-focused conservation strategy does not automatically target areas most valuable for biodiversity, implementing a biodiversity-focused strategy would only slightly increase the costs.

A global predictive model of carbon in mangrove soils

Conservation vs. eradication Whats an ecologist to do when an endangered bird lives in an invasive grass? Ecosystems are complicated networks, with one species relying on another, and managing one species in isolation may damage other members of a community. Lampert et al. (see the Perspective by Buckley and Han) looked at the conflict between eradicating a damaging invasive grass species and protecting an endangered bird species that uses the grass as its home. The most effective management and restoration approach focused not on eradicating the invasive grass as quickly as possible but on making changes slowly enough that the birds could adapt. This approach may prove useful in other situations in which active restoration conflicts with other conservation goals. Science, this issue p. 1028; see also p. 975 Protecting endangered birds that nest in invasive grass requires a measured approach [Also see Perspective by Buckley and Han] Resolving conflicting ecosystem management goals—such as maintaining fisheries while conserving marine species or harvesting timber while preserving habitat—is a widely recognized challenge. Even more challenging may be conflicts between two conservation goals that are typically considered complementary. Here, we model a case where eradication of an invasive plant, hybrid Spartina, threatens the recovery of an endangered bird that uses Spartina for nesting. Achieving both goals requires restoration of native Spartina. We show that the optimal management entails less intensive treatment over longer time scales to fit with the time scale of natural processes. In contrast, both eradication and restoration, when considered separately, would optimally proceed as fast as possible. Thus, managers should simultaneously consider multiple, potentially conflicting goals, which may require flexibility in the timing of expenditures.

Blue Carbon: Coastal Ecosystems, Their Carbon Storage, and Potential for Reducing Emissions

Mangroves are among the most threatened and rapidly vanishing natural environments worldwide. They provide a wide range of ecosystem services and have recently become known for their exceptional capacity to store carbon. Research shows that mangrove conservation may be a lowcost means of reducing CO2 emissions. Accordingly, there is growing interest in developing market mechanisms to credit mangrove conservation projects for associated CO2 emissions reductions. These efforts depend on robust and readily applicable, but currently unavailable, localized estimates of soil carbon. Here, we use over 900 soil carbon measurements, collected in 28 countries by 61 independent studies, to develop a global predictive model for mangrove soil carbon. Using climatological and locational data as predictors, we explore several predictive modeling alternatives, including machine-learning methods. With our predictive model, we construct a global dataset of estimated soil carbon concentrations and stocks on a high-resolution grid (5arc min). We estimate that the global mangrove soil carbon stock is 5.00±0.94Pg C (assuming a 1 meter soil depth) and find this stock is highly variable over space. The amount of carbon per hectare in the world’s most carbon-rich mangroves (approximately 703±38MgC ha �1 ) is roughly a 2.6±0.14 times the amount of carbon per hectare in the world’s most carbon-poor mangroves (approximately 272±49 Mg C ha �1 ). Considerable within country variation in mangrove soil carbon also exists. In Indonesia, the country with the largest mangrove soil carbon stock, we estimate that the most carbon-rich mangroves contain 1.5±0.12 times as much carbon per hectare as the most carbon-poor mangroves. Our results can aid in evaluating benefits from mangrove conservation and designing mangrove conservation policy. Additionally, the results can be used to project changes in mangrove soil carbon stocks based on changing climatological predictors, e.g. to assess the impacts of climate change on mangrove soil carbon stocks. S Online supplementary data available from stacks.iop.org/ERL/9/104013/mmedia

Measuring Benefits from a Marketing Cooperative in the Copper River Fishery

Blue Carbon: Coastal Ecosystems, Their Carbon Storage, and Potential for Reducing Emissions Juha Siikamaki a , James N. Sanchirico b , Sunny Jardine c , David McLaughlin d & Daniel Morris e a Resources for the Future (RFF) b Department of Environmental Science and Policy , University of California , Davis c University of Delaware d RFF e Center for Climate Policy and Economics, RFF Published online: 28 Oct 2013.

Catch share programs in developing countries: A survey of the literature

The degradation of product quality is one form of rent dissipation resulting from incomplete property rights in fisheries. Industry structure and information asymmetries can also lead to underinvestment in product quality, even when property rights are well defined. In this article we empirically examine whether the voluntary formation of a marketing cooperative was able to mitigate market failures that led to the production of inferior-quality fish. Specifically, we use a difference-in-differences estimation strategy to measure the impact that the Copper River Fishermens Cooperative, an Alaskan salmon marketing cooperative, had on ex-vessel salmon prices and salmon quality measures. We find that the cooperative was able to improve product quality, as well as attract and sustain a higher price for its salmon. Our findings provide empirical support for many of the key tenets of cooperative theory. Specifically, we find evidence that marketing cooperatives can address existing market failures, that marketing cooperatives can have advantages in high-quality product markets, and that over time, as a result of their success, marketing cooperatives may lead to lasting producer benefits even though they become obsolete due to nonmember free-riding.