Geology Reports⌕ Search

SEARCH · Geology Reports

Results for “Nature Conservation”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 595 records · Page 33Linked to original sources
USGS2017

Conservation, biodiversity and infectious disease: scientific evidence and policy implications

Habitat destruction and infectious disease are dual threats to nature and people. The potential to simultaneously advance conservation and human health has attracted considerable scientific and popular interest; in particular, many authors have justified conservation action by pointing out potential public health benefits . One major focus of this debate—that biodiversity conservation often decreases infectious disease transmission via the dilution effect—remains contentious. Studies that test for a dilution effect often find a negative association between a diversity metric and a disease risk metric, but how such associations should inform conservation policy remains unclear for several reasons. For one, diversity and infection risk have many definitions, making it possible to identify measures that conform to expectations. Furthermore, the premise that habitat destruction consistently reduces biodiversity is in question, and disturbance or conservation can affect disease in many ways other than through biodiversity change. To date, few studies have examined the broader set of mechanisms by which anthropogenic disturbance or conservation might increase or decrease infectious disease risk to human populations. Due to interconnections between biodiversity change, economics and human behaviour, moving from ecological theory to policy action requires understanding how social and economic factors affect conservation. This Theme Issue arose from a meeting aimed at synthesizing current theory and data on ‘biodiversity, conservation and infectious disease’ (4–6 May 2015). Ecologists, evolutionary biologists, economists, epidemiologists, veterinary scientists, public health professionals, and conservation biologists from around the world discussed the latest research on the ecological and socio-economic links between conservation, biodiversity and infectious disease, and the open questions and controversies in these areas. By combining ecological understanding with insights from the social and economic sciences, the papers in this Theme Issue address the complex relationships, patterns and ecological mechanisms that influence conservation, infectious disease, and the policy options available to protect nature and human health.

Philosophical Transactions of the Royal Society B:↗
USGS2006

Soluble reactive phosphorus (SRP) transport and retention in tropical, rain forest streams draining a volcanic landscape in Costa Rica: In situ SRP amendment to streams and laboratory studies

Soluble reactive phosphorus (SRP) transport/retention was determined in two rain forest streams (Salto, Pantano) draining La Selva Biological Station, Costa Rica. There, SRP levels can be naturally high due to groundwater enriched by geothermal activity within the surfically dormant volcanic landscape, and subsequently discharged at ambient temperature. Combined field and laboratory approaches simulated high but natural geothermal SRP input with the objective of estimating the magnitude of amended SRP retention within high and low SRP settings and determining the underlying mechanisms of SRP retention. First, we examined short-term SRP retention/transport using combined SRP-conservative tracer additions at high natural in situ concentrations. Second, we attempted to observe a DIN response during SRP amendment as an indicator of biological uptake. Third, we determined SRP release/retention using laboratory sediment assays under control and biologically inhibited conditions. Short-term in situ tracer-SRP additions indicated retention in both naturally high and low SRP reaches. Retention of added SRP mass in Upper Salto (low SRP) was 17% (7.5 mg-P m-2 h-1), and 20% (10.9 mg-P m-2 h -1) in Lower Salto (high SRP). No DIN response in either nitrate or ammonium was observed. Laboratory assays using fresh Lower Salto sediments indicated SRP release (15.4 ?? 5.9 ??g-P g dry wt.-1 h -1), when incubated in filter sterilized Salto water at ambient P concentration, but retention when incubated in filter sterilized river water amended to 2.0 mg SRP l-1 (233.2 ?? 5.8 ??g-P g dry wt. -1 h-1). SRP uptake/release was similar in both control- and biocide-treated sediments indicating predominantly abiotic retention. High SRP retention even under biologically saturated conditions, absence of a DIN response to amendment, patterns of desorption following amendment, and similar patterns of retention and release under control and biologically inhibited conditions all indicated predominantly abiotic P flux. ?? 2006 Springer Science+Business Media, Inc.

Biogeochemistry↗
USGS2009

Using occupancy models of forest breeding birds to prioritize conservation planning

As urban development continues to encroach on the natural and rural landscape, land-use planners struggle to identify high priority conservation areas for protection. Although knowing where urban-sensitive species may be occurring on the landscape would facilitate conservation planning, research efforts are often not sufficiently designed to make quality predictions at unknown locations. Recent advances in occupancy modeling allow for more precise estimates of occupancy by accounting for differences in detectability. We applied these techniques to produce robust estimates of habitat occupancy for a subset of forest breeding birds, a group that has been shown to be sensitive to urbanization, in a rapidly urbanizing yet biological diverse region of New York State. We found that detection probability ranged widely across species, from 0.05 to 0.8. Our models suggest that detection probability declined with increasing forest fragmentation. We also found that the probability of occupancy of forest breeding birds is negatively influenced by increasing perimeter-area ratio of forest fragments and urbanization in the surrounding habitat matrix. We capitalized on our random sampling design to produce spatially explicit models that predict high priority conservation areas across the entire region, where interior-species were most likely to occur. Finally, we use our predictive maps to demonstrate how a strict sampling design coupled with occupancy modeling can be a valuable tool for prioritizing biodiversity conservation in land-use planning. ?? 2009 Elsevier Ltd.

Biological Conservation↗
USGS2009

Genetic conservation and paddlefish propagation

The conservation of genetic diversity of our natural resources is overwhelmingly one of the central foci of 21st century management practices. Three recommendations related to the conservation of paddlefish Polyodon spathula genetic diversity are to (1) identify genetic diversity at both nuclear and mitochondrial DNA loci using a suggested list of 20 sampling locations, (2) use genetic diversity estimates to develop genetic management units, and (3) identify broodstock sources to minimize effects of supplemental stocking on the genetic integrity of native paddlefish populations. We review previous genetic work on paddlefish and described key principles and concepts associated with maintaining genetic diversity within and among paddlefish populations and also present a genetic case study of current paddlefish propagation at the U.S. Fish and Wildlife Service Gavins Point National Fish Hatchery. This study confirmed that three potential sources of broodfish were genetically indistinguishable at the loci examined, allowing the management agencies cooperating on this program flexibility in sampling gametes. This study also showed significant bias in the hatchery occurred in terms of male reproductive contribution, which resulted in a shift in the genetic diversity of progeny compared to the broodfish. This shift was shown to result from differential male contributions, partially attributed to the mode of egg fertilization. Genetic insights enable implementation of a paddlefish propagation program within an adaptive management strategy that conserves inherent genetic diversity while achieving demographic goals.

American Fisheries Society Symposium↗
USGS2022

Murky waters: Divergent ways scientists, practitioners, and landowners evaluate beaver mimicry

Beaver mimicry is a fast-growing conservation technique to restore streams and manage water that is gaining popularity within the natural resource management community because of a wide variety of claimed socio-environmental benefits. Despite a growing number of projects, many questions and concerns about beaver mimicry remain. This study draws on qualitative data from 49 interviews with scientists, practitioners, and landowners, to explore the question of how beaver mimicry projects continue to be promoted and implemented, despite the lack of comprehensive scientific studies and unclear regulatory requirements. Specifically, we investigate how these three groups differentially assess the salience, credibility, and legitimacy of evidence for beaver mimicry and analyze how those assessments affect each group’s conclusions about the feasibility, desirability, and scalability of beaver mimicry. By highlighting the interaction between how someone assesses evidence and how they draw conclusions about an emerging natural resource management approach, we draw attention to the roles of experiential evidence and scientific data in debates over beaver mimicry. Our research emphasizes that understanding how different groups perceive salience, credibility, and legitimacy of scientific information is necessary for understanding how they make assessments about conservation and natural resource management strategies.

Ecology and Society↗
USGS2019

Review of Sky dance of the woodcock: The habits and habitats of a strange little bird by Greg Hoch

American Woodcock ( Scolopax minor ) have enthralled conservationists (including Aldo Leopold), bird watchers, wildlife enthusiasts, hunters, and others interested in the natural world for centuries. No doubt, woodcock also have enthralled humans in North America for millennia prior to written descriptions of the woodcock’s courtship displays, habitat preferences, and curious behavior and anatomy. As perhaps the most extensively studied species of shorebird in the world, there is a rich and extensive literature, both scientific and popular, focused on woodcock ecology, behavior, and hunting. To that extensive body of literature, Sky Dance of the Woodcock provides an updated summary of their natural history, habitat relations, and conservation. Sky Dance of the Woodcock takes its title from the courtship display of male woodcock, which consists of an elaborate aerial flight incorporating sound produced both vocally and mechanically via highly modified flight feathers. The aerial displays are accompanied by similarly unusual behavior on the ground, including a distinctive ‘peent’ call. This courtship display happens across much of eastern North America each spring, and Hoch uses this wonder to capture the imagination of the readers of his text. Hoch begins the book with an overview of some of the mystery and fascination surrounding woodcock and builds from that opening to describe woodcock anatomy, natural history, and behavior, before describing their courtship display in greater detail. From there, Hoch describes woodcock-habitat relations, provides a historical overview of woodcock hunting, identifies current threats to woodcock populations, summarizes past and recent woodcock research, and finally, presents an updated overview of woodcock conservation and habitat management. Throughout, there is sometimes surprising information about things as simple as what woodcock eat, to more complex assessment of how woodcock use landscapes and migrate to and from spring and summer breeding areas. This book will undoubtedly appeal to woodcock enthusiasts of a variety to stripes. Woodcock hunters and bird watchers alike will learn something about woodcock-habitat relations, behavior, and conservation. Professional biologists and researchers will benefit from Hoch’s synthesis of a wide range of information about woodcock, and landowners and managers can use some of the concepts in this book to inform their decisions about how to manage lands under their control. Along the way, everyone who reads Sky Dance of the Woodcock is likely to come away with an enhanced appreciation of this captivating bird.

Prairie Naturalist↗
USGS2010

Status of the California condor (Gymnogyps californianus) and efforts to achieve its recovery

The California Condor ( Gymnogyps californianus ; hereafter "condor"; Fig. 1) has long been symbolic of avian conservation in the United States. Its large size, inquisitiveness, and association with remote places make it highly charismatic, and its decline to the brink of extinction aroused a continuing public interest in its plight. By 1982, only 22 individuals remained of this species whose range once encompassed much of North America. The last wild bird was trapped and brought into captivity in 1987, which rendered the species extinct in the wild (Snyder and Snyder 1989). In the 1980s, some questioned whether viable populations could ever again exist in the natural environment, and whether limited conservation funds should be expended on what they viewed as a hopeless cause (Pitelka 1981). Nevertheless, since that low point, a captive-breeding and release program has increased the total population by an order of magnitude, and condors fly free again in California, Arizona, Utah, and Baja California, Mexico (Fig. 2). At this writing (summer 2009), more than 350 condors exist, 180 of which are in the wild (J. Grantham pers. comm.). The free-living birds face severe challenges, however, and receive constant human assistance. The intensive management applied to the free-living populations, as well as the ongoing monitoring and captive-breeding programs, are tremendously expensive and become more so as the population grows. Thus, the program has reached a crossroads, caught between the financial and logistical pressures required to maintain an increasing number of condors in the wild and the environmental problems that preclude establishment of naturally sustainable, free-ranging populations.

The Auk↗
USGS2018

Carnivore hotspots in Peninsular Malaysia and their landscape attributes

Mammalian carnivores play a vital role in ecosystem functioning. However, they are prone to extinction because of low population densities and growth rates, and high levels of persecution or exploitation. In tropical biodiversity hotspots such as Peninsular Malaysia, rapid conversion of natural habitats threatens the persistence of this vulnerable group of animals. Here, we carried out the first comprehensive literature review on 31 carnivore species reported to occur in Peninsular Malaysia and updated their probable distribution. We georeferenced 375 observations of 28 species of carnivore from 89 unique geographic locations using records spanning 1948 to 2014. Using the Getis-Ord Gi*statistic and weighted survey records by IUCN Red List status, we identified hotspots of species that were of conservation concern and built regression models to identify environmental and anthropogenic landscape factors associated with Getis-Ord Gi* z scores. Our analyses identified two carnivore hotspots that were spatially concordant with two of the peninsula’s largest and most contiguous forest complexes, associated with Taman Negara National Park and Royal Belum State Park. A cold spot overlapped with the southwestern region of the Peninsula, reflecting the disappearance of carnivores with higher conservation rankings from increasingly fragmented natural habitats. Getis-Ord Gi* z scores were negatively associated with elevation, and positively associated with the proportion of natural land cover and distance from the capital city. Malaysia contains some of the world’s most diverse carnivore assemblages, but recent rates of forest loss are some of the highest in the world. Reducing poaching and maintaining large, contiguous tracts of lowland forests will be crucial, not only for the persistence of threatened carnivores, but for many mammalian species in general.

PLoS ONE↗
USGS2015

A framework for modeling anthropogenic impacts on waterbird habitats: addressing future uncertainty in conservation planning

The amount and quality of natural resources available for terrestrial and aquatic wildlife habitats are expected to decrease throughout the world in areas that are intensively managed for urban and agricultural uses. Changes in climate and management of increasingly limited water supplies may further impact water resources essential for sustaining habitats. In this report, we document adapting a Water Evaluation and Planning (WEAP) system model for the Central Valley of California. We demonstrate using this adapted model (WEAP-CV wh ) to evaluate impacts produced from plausible future scenarios on agricultural and wetland habitats used by waterbirds and other wildlife. Processed output from WEAP-CV wh indicated varying levels of impact caused by projected climate, urbanization, and water supply management in scenarios used to exemplify this approach. Among scenarios, the NCAR-CCSM3 A2 climate projection had a greater impact than the CNRM-CM3 B1 climate projection, whereas expansive urbanization had a greater impact than strategic urbanization, on annual availability of waterbird habitat. Scenarios including extensive rice-idling or substantial instream flow requirements on important water supply sources produced large impacts on annual availability of waterbird habitat. In the year corresponding with the greatest habitat reduction for each scenario, the scenario including instream flow requirements resulted in the greatest decrease in habitats throughout all months of the wintering period relative to other scenarios. This approach provides a new and useful tool for habitat conservation planning in the Central Valley and a model to guide similar research investigations aiming to inform conservation, management, and restoration of important wildlife habitats.

California↗
USGS2021

Mammal species composition and habitat associations in a commercial forest and mixed-plantation landscape

Commercial forest plantations of fast-growing species have been established globally to meet increasing demands for timber, pulpwood, and other wood products. Industrial plantations may contribute to tropical forest conservation by reducing exploitation of primary and secondary natural forests. Whether such plantations can support critical elements of biodiversity, including provision of habitat and movement corridors for species of conservation concern, is an important question in Southeast Asia. Our objectives were to investigate relationships between habitat gradients and community attributes of medium-sized to large mammals in a mixed plantation mosaic in Bengkoka Peninsula, Sabah, East Malaysia. Data on mammals were collected using 59 remote camera stations deployed for a minimum of 21 days (24-hour sampling occasions) in three major land-use types: natural forest, Acacia plantations, and non- Acacia plantations (oil palm, rubber, young Eucalyptus pellita ). We used sample-based rarefaction to evaluate variation in species richness with land use. We used generalized linear models and ordination analyses to evaluate whether variation in mammal detections and species composition was associated with habitat gradients. We recorded >22 mammal species over 1572 sampling occasions. Natural forest area was positively associated with mammal species richness and detections of threatened mammals. Overall detections of mammals increased with decreasing elevation, but decreased within, and close to, Acacia plantations. Detections of threatened mammals increased with greater proportions of natural forest and Acacia and increasing proximity to roads. Sample-based rarefaction indicated that species richness of mammals in Acacia and natural forest was considerably higher than observed. Both natural forest and Acacia plantations shared similar values for species richness and diversity, but non- Acacia plantations scored lower in both metrics. Mammal species composition differed among different types of land use. Smaller generalists used non- Acacia plantation forests. A variety of other mammals including some threatened species used natural forest, Acacia , or a combination of the two. Acacia plantations possess attributes supporting a diversity of mammal species, including those we defined as threatened based on IUCN criteria. However, this is likely a function of the habitat mosaic with natural forest in the study area and the mangrove forests on the fringes of the peninsula serving as refuges of mammal diversity. Retention and restoration of natural and mangrove forests may therefore enhance the conservation potential of industrial Acacia plantations. Additionally, controlled road access in conjunction with anti-poaching operations and strengthening public awareness are essential to reduce the threat of overexploitation.

Forest Ecology and Management↗
USGS2006

Recharge processes drive sulfate reduction in an alluvial aquifer contaminated with landfill leachate

Natural attenuation of contaminants in groundwater depends on an adequate supply of electron acceptors to stimulate biodegradation. In an alluvial aquifer contaminated with leachate from an unlined municipal landfill, the mechanism of recharge infiltration was investigated as a source of electron acceptors. Water samples were collected monthly at closely spaced intervals in the top 2 m of the saturated zone from a leachate-contaminated well and an uncontaminated well, and analyzed for δ 18 O, δ 2 H, non-volatile dissolved organic carbon (NVDOC), SO 4 2− , NO 3 − and Cl − . Monthly recharge amounts were quantified using the offset of the δ 18 O or δ 2 H from the local meteoric water line as a parameter to distinguish water types, as evaporation and methanogenesis caused isotopic enrichment in waters from different sources. Presence of dissolved SO 4 2− in the top 1 to 2 m of the saturated zone was associated with recharge; SO 4 2− averaged 2.2 mM, with maximum concentrations of 15 mM. Nitrate was observed near the water table at the contaminated site at concentrations up to 4.6 mM. Temporal monitoring of δ 2 H and SO 4 2− showed that vertical transport of recharge carried SO 4 2− to depths up to 1.75 m below the water table, supplying an additional electron acceptor to the predominantly methanogenic leachate plume. Measurements of δ 34 S in SO 4 2− indicated both SO 4 2− reduction and sulfide oxidation were occurring in the aquifer. Depth-integrated net SO 4 2− reduction rates, calculated using the natural Cl − gradient as a conservative tracer, ranged from 7.5 × 10 − 3 to 0.61 mM·d − 1 (over various depth intervals from 0.45 to 1.75 m). Sulfate reduction occurred at both the contaminated and uncontaminated sites; however, median SO 4 2− reduction rates were higher at the contaminated site. Although estimated SO 4 2− reduction rates are relatively high, significant decreases in NVDOC were not observed at the contaminated site. Organic compounds more labile than the leachate NVDOC may be present in the root zone, and SO 4 2− reduction may be coupled to methane oxidation. The results show that sulfur (and possibly nitrogen) redox processes within the top 2 m of the aquifer are directly related to recharge timing and seasonal water level changes in the aquifer. The results suggest that SO 4 2− reduction associated with the infiltration of recharge may be a significant factor affecting natural attenuation of contaminants in alluvial aquifers.

Journal of Contaminant Hydrology↗
USGS2020

Introduction to resource allocation

With ongoing habitat loss and degradation, ever-increasing threats to biodiversity, and limited funding for conservation and management, nearly every natural resource manager routinely faces difficult resource allocation problems. Funding and capacity for natural resource management rarely meet the need, and informed resource allocations are increasingly important. These decision problems include not only habitat and species management but also a wide variety of administrative decisions. Ranking projects or plans by benefit-cost ratio is an intuitive, heuristic approach to resource allocation but may be inefficient. We present a general resource allocation framework in which these decision problems can be stated mathematically, making it relatively easy to find solutions using mathematical programming such as linear programming. amenable to Linear programming and other constrained optimization routines, which can be implemented in common software applications and used with a wide variety of decision problems, including project prioritization and portfolio decisions. Constrained optimization has advantages over intuitive benefit-cost ratios and can accommodate single and multiple objective problems. We also introduce the three case studies in this section illustrating a variety of resource allocation problems: the first case study shows how to select cost-effective management actions for discrete management units such as wetlands or grassland patches; the second, how to use a patch dynamics model to allocation allocate resources for a reserve network that protects habitat for multiple species of conservation concern; and the third, how to use stochastic simulation to determine allocation of resources in space and time for invasive species management.

Book chapter↗
USGS2022

The gap between experts, farmers and non-farmers on perceived environmental vulnerability and the influence of values and beliefs

Science has played a mixed role in guiding conservation and sustainability-oriented decision-making by individuals, policymakers, institutions, and governments. Not all science-based conservation and sustainability initiatives that address issues facing humanity and ecosystems and global problems have gained public support. Conservation decisions and policy prescriptions are and may be based on perceptions about and experiences with the environment, local land use, and ecosystems that may not align with or be grounded in science or evidence from experts in the field. Values, beliefs, and perceptions associated with nature play a critical role in how individuals view biodiversity conservation, sustainability, and natural resource management . This study first examines the gap between experts (scientists and other field experts) and the public (farmers and non-farmers) about the state of water and land resources, wildlife and associated habitats, and aquatic biodiversity in the Smoky Hill River Watershed in western Kansas. Second, the study examines the role that values and beliefs play in shaping environmental perceptions for farmers and non-farmers. Analysis confirms that a gap between experts and farmers/non-farmers does exist, especially with respect to the state of the Ogallala Aquifer, playas, rivers and streams, lakes and reservoirs, native grasslands, wildlife habitats, farmland, native fish populations, and wildlife species. Ordered-logistic regression analyses, meanwhile, indicate that farmer and non-farmer perceptions about the state of the local environment are influenced by traditional and self-interested values, as well as environmental values and beliefs, but less so by religiosity and political ideology. Despite broad takeaways, results exhibited heterogeneity across the farmer and non-farmer subpopulations. If environmental professionals cannot align ecological data, stakeholders’ values/perceptions, and policies, then the existing body of technical research and management on sustainability in natural and social sciences may be of little value.

Journal of Environmental Management↗
USGS2015

Book review: Mosquito eradication: The story of killing Campto

In 1826, the paradise that was the Hawaiian Islands was changed forever when the first mosquito species was accidentally introduced to the island of Maui. Though it has not lived up to its potential as a vector of human disease in the islands, Culex quinquefasciatus and the avian pathogens it transmits laid waste to perhaps the world's most remarkable insular avifauna. Today the lowland native forests, once deafening with birdsong, are largely devoid of native birds and Cx. quinquefasciatus has become an inextricable part of our natural areas. In the Hawaiian Islands, the conservation community struggles to keep invasive species out and to control a number of species that have become naturalized. Despite the millions of dollars spent, these efforts never seem enough to slow the erosion of our native biota. The restoration and long-term preservation of Hawaiian forest birds depend on the nearly complete control of mosquito-borne avian disease, an obstacle that to many land managers appears insurmountable. To rally hope in Hawai`i, the conservation community needs to see a success. As a Pacific island, Hawai`i shares similar conservation problems with New Zealand and has often looked to that nation for innovation and inspiration. Mosquito Eradication: The Story of Killing Campto may be our latest inspiration. Review info: Mosquito Eradication: The Story of Killing Campto. By Brian H. Kay, and Richard C. Russell (eds.), 2013. ISBN: 978-1486300570, 280 pp.

American Entomologist↗
USGS2022

Redundancy analysis reveals complex den use patterns by eastern spotted skunks, a conditional specialist

Wildlife managers tasked with understanding habitat and resource selection at the population level attempt to characterize patterns in nature that aid and inform conservation. Resource selection functions (RSFs), such as discrete choice analyses, are the standard convention to characterize the effects of habitat attributes on resource selection patterns. These tools are invaluable for wildlife management and conservation and have proven successful in numerous studies. However, the analysis of small datasets using RSF becomes problematic when attempting to account for complex sources of variation, and the inclusion of factors such as weather or intrinsic variation on target species' response may produce models with poor predictive ability. We compared the application of generalized linear mixed-effects modeling (GLMM) and redundancy analysis (RDA) on Appalachian spotted skunk ( Spilogale putorius putorius ) den selection data at four study sites within the George Washington, Jefferson, and Monongahela National Forests, and surrounding private lands in the Appalachian Mountains of western Virginia and northeastern West Virginia. We assessed the need for the inclusion of alternative sources of variation (i.e., weather conditions and individual intrinsic variation) in addition to standard habitat attributes to better identify sources of variation in den selection. The RDA elucidated complex and opposing relationships, whereby den type use was based on reproductive status or weather condition, which were not evident in the GLMM model that relied solely on habitat measures. Our results demonstrated the importance of examining resource selection data using multivariate techniques in addition to conventional discrete choice analyses to better understand intricate habitat–species relationships, especially for small datasets. Furthermore, from our analyses, we proposed that spotted skunks are neither a true generalist nor specialist species. We introduced and define the term “conditional specialist” to represent a species that is conditionally selective of a given resource in response to one or more current environmental or intrinsic conditions.

Viginia, West Virginia↗
USGS2021

Managing for RADical ecosystem change: Applying the Resist-Accept-Direct (RAD) framework

Ecosystem transformation involves the emergence of persistent ecological or social–ecological systems that diverge, dramatically and irreversibly, from prior ecosystem structure and function. Such transformations are occurring at increasing rates across the planet in response to changes in climate, land use, and other factors. Consequently, a dynamic view of ecosystem processes that accommodates rapid, irreversible change will be critical for effectively conserving fish, wildlife, and other natural resources, and maintaining ecosystem services. However, managing ecosystems toward states with novel structure and function is an inherently unpredictable and difficult task. Managers navigating ecosystem transformation can benefit from considering broader objectives, beyond a traditional focus on resisting ecosystem change, by also considering whether accepting inevitable change or directing it along some desirable pathway is more feasible (that is, practical and appropriate) under some circumstances (the RAD framework). By explicitly acknowledging transformation and implementing an iterative RAD approach, natural resource managers can be deliberate and strategic in addressing profound ecosystem change.

Frontiers in Ecology and the Environment↗
USGS2016

CO2 time series patterns in contrasting headwater streams of North America

We explored the underlying patterns of temporal stream CO 2 partial pressure ( p CO 2 ) variability using highfrequency sensors in seven disparate headwater streams distributed across the northern hemisphere. We also compared this dataset of [40,000 p CO 2 records with other published records from lotic systems. Individual stream sites exhibited relatively distinct p CO 2 patterns over time with few consistent traits across sites. Some sites showed strong diel variability, some exhibited increasing p CO 2 with increasing discharge, whereas other streams had reduced p CO 2 with increasing discharge or no clear response to changes in flow. The only ‘‘universal’’ signature observed in headwater streams was a late summer p CO 2 maxima that was likely driven by greatest rates of organic matter respiration due to highest annual temperatures. However, we did not observe this seasonal pattern in a southern hardwood forest site, likely because the region was transitioning from a severe drought. This work clearly illustrates the heterogeneous nature of headwater streams, and highlights the idiosyncratic nature of a non-conservative solute that is jointly influenced by physics, hydrology, and biology. We suggest that future researchers carefully select sensor locations (within and among streams) and provide additional contextual information when attempting to explain p CO 2 patterns.

Alaska, Colorado, Georgia, Puerto Rico, Vermont, W↗
USGS2018

Evaluating anthropogenic landscape alterations as wildlife hazards, with wind farms as an example

Anthropogenic alterations to landscape are indicators of potential compromise of that landscape’s ecology . We describe how alterations can be assessed as ‘hazards’ to wildlife through a sequence of three steps: diagnosing the means by which the hazard acts on individual organisms at risk; estimating the fitness cost of the hazard to those individuals and the rate at which that cost occurs; and translating that cost rate into a demographic cost by identifying the relevant demographically-closed population. We exploit the conservation-oriented literature on wind farms to illustrate this conceptual scheme. For wind farms, the third component has received less attention than the first two, which suggests it is the most challenging of the three components. A wind farm provides an example of a ‘spatially localized hazard’, i.e., a discrete alteration of landscape hazardous to some population but of which there are some individuals that do not interact directly with the hazard themselves but nevertheless suffer a reduction in fitness in terms of their contribution to the next generation. Spatially localized hazards are identified via the third component of the scheme and are of particular conservation concern as, by their nature, their depredations on wildlife may be underestimated without an appropriate population-level estimation of the demographic cost of the hazard.

Ecological Indicators↗