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Palaeodata-informed modelling of large carbon losses from recent burning of boreal forests
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Wildfires play a key role in the boreal forest carbon cycle(1,2), and models suggest that accelerated burning will increase boreal C emissions in the coming century (3). However, these predictions may be compromised because brief observational records provide limited constraints to model initial conditions (4). We confronted this limitation by using palaeoenvironmental data to drive simulations of long-term C dynamics in the Alaskan bo- real forest. Results show that fire was the dominant control on C cycling over the past millennium, with changes in fire frequency accounting for 84% of C stock variability. A recent rise in fire frequency inferred from the palaeorecord5 led to simulated C losses of 1.4 kg C m?2(12% of ecosystem C stocks) from 1950 to 2006. In stark contrast, a small net C sink of 0.3 kg C m?2 occurred if the past fire regime was assumed to be similar to the modern regime, as is common in models of C dynamics. Although boreal fire regimes are heterogeneous, recent trends6 and future projections (7) point to increasing fire activity in response to climate warming throughout the biome. Thus, predictions (8) that terrestrial C sinks of northern high latitudes will mitigate rising atmospheric CO2 may be over-optimistic.
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Climate Science Documents
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Temporal dynamics of a commensal network of cavity-nesting vertebrates: increased diversity during an insect outbreak
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Network analysis offers insight into the structure and function of ecological
communities, but little is known about how empirical networks change over time during
perturbations. ‘‘Nest webs’’ are commensal networks that link secondary cavity-nesting
vertebrates (e.g., bluebirds, ducks, and squirrels, which depend on tree cavities for nesting)
with the excavators (e.g., woodpeckers) that produce cavities. In central British Columbia,
Canada, Northern Flicker (Colaptes auratus) is considered a keystone excavator, providing
most cavities for secondary cavity-nesters. However, roles of species in the network, and
overall network architecture, are expected to vary with population fluctuations. Many
excavator species increased in abundance in association with a pulse of food (adult and larval
beetles) during an outbreak of mountain pine beetle (Dendroctonus ponderosae), which peaked
in 2003–2004. We studied nest-web dynamics from 1998 to 2011 to determine how network
architecture changed during this resource pulse.Cavity availability increased at the onset of the beetle outbreak and peaked in 2005. During and after the outbreak, secondary cavity-nesters increased their use of cavities made by five species of beetle-eating excavators, and decreased their use of flicker cavities. We found low link turnover, with 74% of links conserved from year to year. Nevertheless, the network
increased in evenness and diversity of interactions, and declined slightly in nestedness and
niche overlap. These patterns remained evident seven years after the beetle outbreak,
suggesting a legacy effect. In contrast to previous snapshot studies of nest webs, our dynamic approach reveals how the role of each cavity producer, and thus quantitative network architecture, can vary over
time. The increase in interaction diversity with the beetle outbreak adds to growing evidence
that insect outbreaks can increase components of biodiversity in forest ecosystems at various
temporal scales. The observed changes in (quantitative) network architecture contrast with the
relatively stable (qualitative) architecture of empirical mutualistic networks that have been
studied to date. However, they are consistent with recent theory on the importance of
population fluctuations in driving network architecture. Our results support the view that
models should allow for the possibility of rewiring (species switching partners) to avoid
overestimation of secondary extinction risk.
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Applying ecological criteria to marine reserve design: A case study from the California Channel Islands
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Reference which describes the steps involved in designing a network of marine reserves for conservation and fisheries management.
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Marxan Training Resources
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Marxan Training Suggested Readings
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Protected Areas: Goals, Limitations, and Design
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This reference focuses on the functions, design, and limitations of protected areas and the processes of conservation planning.
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Marxan Training Resources
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Marxan Training Suggested Readings
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Three new darter species of the Etheostoma percnurum species complex (Percidae, subgenus Catonotus) from the Tennessee and Cumberland River Drainages
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The federally endangered Duskytail Darter, Etheostoma percnurum Jenkins, is known from only six highly disjunct populations in the Tennessee and Cumberland river drainages of Kentucky, Tennessee, and Virginia. Only four are extant. Variation in morphology including meristics, morphometrics, and pigmentation was examined among the four extant populations and limited specimens from the two extirpated populations (Abrams Creek and South Fork Holston River). Analyses of these data found each of the extant populations is morphologically diagnosable. The few specimens avail- able from Abrams Creek and South Fork Holston River prevented thorough assessment of variation, and these were grouped with their closest geographic counterparts, Citico Creek, and Little River, respectively. Three new morphologi- cally diagnosable species are described: E. sitikuense, the Citico Darter, from Citico Creek, Abrams Creek, and Tellico River (Tennessee River system); E. marmorpinnum, the Marbled Darter, from the Little River and South Fork Holston River (Tennessee River system); and E. lemniscatum, the Tuxedo Darter, from the Big South Fork (Cumberland River system). Each species warrants federal protection as an endangered species.
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Reports & Documents
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Toward rigorous use of expert knowledge in ecological research
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Practicing ecologists who excel at their work (‘‘experts’’) hold a wealth of knowledge. This knowledge offers a wide range of opportunities for application in ecological research and natural resource decision-making. While experts are often consulted ad-hoc, their contributions are not widely acknowledged. These informal applications of expert knowledge lead to concerns about a lack of transparency and repeatability, causing distrust of this knowledge source in the scientific community. Here, we address these concerns with an exploration of the diversity of expert knowledge and of rigorous methods in its use. The effective use of expert knowledge hinges on an awareness of the spectrum of experts and their expertise, which varies by breadth of perspective and critical assessment. Also, experts express their knowledge in different forms depending on the degree of contextualization with other information. Careful matching of experts to application is therefore essential and has to go beyond a simple fitting of the expert to the knowledge domain. The standards for the collection and use of expert knowledge should be as rigorous as for empirical data. This involves knowing when it is appropriate to use expert knowledge and how to identify and select suitable experts. Further, it requires a careful plan for the collection, analysis and validation of the knowledge. The knowledge held by expert practitioners is too valuable to be ignored. But only when thorough methods are applied, can the application of expert knowledge be as valid as the use of empirical data. The responsibility for the effective and rigorous use of expert knowledge lies with the researchers.
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Six Common Mistakes in Conservation Priority Setting
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A vast number of prioritization schemes have been developed to help conservation navigate tough decisions about the allocation of finite resources. However, the application of quantitative approaches to setting priorities in conservation frequently includes mistakes that can undermine their authors’ intention to be more rigorous and scientific in the way priorities are established and resources allocated. Drawing on well-established principles of decision science, we highlight 6 mistakes commonly associated with setting priorities for conservation: not acknowledging conservation plans are prioritizations; trying to solve an ill- defined problem; not prioritizing actions; arbitrariness; hidden value judgments; and not acknowledging risk of failure. We explain these mistakes and offer a path to help conservation planners avoid making the same mistakes in future prioritizations.
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Reports & Documents
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Plan for the Population Restoration and Conservation of Imperiled Freshwater Mollusks of the Cumberland Region
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The goal of this Plan is to provide a framework for the restoration of freshwater mollusk resources and their ecological functions to appropriate reaches of the Cumberlandian Region through the reintroduction, augmentation (R/A) and controlled propagation of priority mollusks. The Plan prioritizes propagation and R/A activities for Region mollusks and provides guidelines for resource managers and recovery partners. The Plan is not a legal document and is not intended to replace or supersede published recovery plans for listed mollusks.
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Reports & Documents
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Climate Change: Future Federal Adaptation Efforts Could Better Support Local Infrastructure Decision Makers
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The federal government invests billions of dollars annually in infrastructure, such as roads and bridges, facing increasing risks from climate change. Adaptation—defined as adjustments to natural or human systems in response to actual or expected climate change— can help manage these risks by making infrastructure more resilient. GAO was asked to examine issues related to infrastructure decision making and climate change. This report examines (1) the impacts of climate change on roads and bridges, wastewater systems, and NASA centers; (2) the extent to which climate change is incorporated into infrastructure planning; (3) factors that enabled some decision makers to implement adaptive measures; and (4) federal efforts to address local adaptation needs, as well as potential opportunities for improvement. GAO reviewed climate change assessments; analyzed relevant reports; interviewed stakeholders from professional associations and federal agencies; and visited infrastructure projects and interviewed local decision makers at seven sites where adaptive measures have been implemented.
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National Fish, Wildlife, & Plants Climate Adaptation Strategy
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The purpose of the National Fish, Wildlife and Plants Climate Adaptation Strategy is to inspire and enable natural resource administrators, elected officials, and other decision makers to take action to adapt to a changing climate. Adaptation actions are vital to sustaining the nation’s ecosystems and natural resources — as well as the human uses and values that the natural world provides.
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General Resources Holdings
