Browsing by Subject "Environmental Sciences & Ecology"

Now showing 1 - 20 of 66

Open Access
A novel approach to assess livestock management effects on biodiversity of drylands
(Ecological Indicators, 2015-01-01) Chillo, V; Ojeda, RA; Anand, M; Reynolds, JF
In drylands livestock grazing is the main production activity, but overgrazing due to mismanagement is a major cause of biodiversity loss. Continuous grazing around water sources generates a radial gradient of grazing intensity called the piosphere. The ecological sustainability of this system is questionable and alternative management needs to be evaluated. We apply simple indicators of species response to grazing gradients, and we propose a novel methodological approach to compare community response to grazing gradients (double reciprocal analysis). We assessed degradation gradients of biodiversity under different management strategies in semiarid rangelands of the Monte desert (Argentina) by analyzing changes in vegetation, ants and small mammal richness and diversity, and variation due to seasonality. At the species level, we determined the trend in abundance of each species along the gradient, and the potential cross-taxa surrogacy. At the community level, the new methodological consists of assessing the magnitude of biodiversity degradation along different piospheres by comparing the slopes of linear functions obtained by the double reciprocal analysis. We found that most species showed a decreasing trend along the gradient under continuous grazing; while under rotational grazing fewer species showed a decreasing trend, and a neutral trend (no change in the abundance along the gradient of grazing intensity) was the most common. We found that vegetation cannot be used as a surrogacy taxon of animal response. Moreover, weak cross-taxa surrogacy was found only for animal assemblages during the wet season. The double reciprocal analysis allowed for comparison of multi-taxa response under different seasons and management types. By its application, we found that constrains in precipitation interacted with disturbance by increasing the negative effect of grazing on vegetation, but not on animal assemblages. Continuous grazing causes biodiversity loss in all situations. Rotational grazing prevents the occurrence of vegetation degradation and maintains higher levels of animal diversity, acting as an opportunity for biodiversity conservation under current scenarios of land use extensification. Our approach highlights the importance of considering multi-taxa and intrinsic variability in the analysis, and should be of value to managers concerned with biodiversity conservation.
Open Access
Assessing the effects of elephant foraging on the structure and diversity of an Afrotropical forest
(Biotropica, 2020-05-01) Rosin, Cooper; Beals, Kendall K; Belovitch, Michael W; Harrison, Ruby E; Pendred, Megan; Sullivan, Megan K; Yao, Nicolas; Poulsen, John R
African forest elephants (Loxodonta cyclotis) are ecosystem engineers that browse and damage large quantities of vegetation during their foraging and movement. Though elephant trail networks and clearings are conspicuous features of many African forests, the consequences of elephant foraging for forest structure and diversity are poorly documented. In this study in northeastern Gabon, we compare stem size, stem density, proportional damage, species diversity, and species relative abundance of seedlings and saplings in the vicinity of seven tree species that produce elephant-preferred fruits (“elephant trees”) relative to control trees that do not. Across 34 survey trees, with a combined census area of 2.04 ha, we recorded data on 26,128 woody stems in three sizes classes. Compared with control trees, the area around elephant trees had the following: (a) a significantly greater proportion of damaged seedlings and a marginally greater proportion of damaged saplings (with 82% and 24% greater odds of damage, respectively); (b) no significant difference in stem density or species diversity; and (c) a significantly greater relative abundance of seedlings of elephant tree species. Increasing distance away from focal elephant trees was associated with significantly reduced sapling stem damage, significantly increased sapling stem density, and significantly increased sapling species diversity. Considered in sum, our results suggest that elephants can affect the structure and diversity of Afrotropical forests through their foraging activities, with some variation based on location and plant size class. Developing a more complete understanding of elephants’ ecological effects will require continued research, ideally with manipulative experiments. Abstract in French is available with online material.
Open Access
Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire: An expert assessment
(Environmental Research Letters, 2016-03-07) Abbott, BW; Jones, JB; Schuur, EAG; Chapin, FS; Bowden, WB; Bret-Harte, MS; Epstein, HE; Flannigan, MD; Harms, TK; Hollingsworth, TN; Mack, MC; McGuire, AD; Natali, SM; Rocha, AV; Tank, SE; Turetsky, MR; Vonk, JE; Wickland, KP; Aiken, GR; Alexander, HD; Amon, RMW; Benscoter, BW; Bergeron, Y; Bishop, K; Blarquez, O; Bond-Lamberty, B; Breen, AL; Buffam, I; Cai, Y; Carcaillet, C; Carey, SK; Chen, JM; Chen, HYH; Christensen, TR; Cooper, LW; Cornelissen, JHC; De Groot, WJ; Deluca, TH; Dorrepaal, E; Fetcher, N; Finlay, JC; Forbes, BC; French, NHF; Gauthier, S; Girardin, MP; Goetz, SJ; Goldammer, JG; Gough, L; Grogan, P; Guo, L; Higuera, PE; Hinzman, L; Hu, FS; Hugelius, G; Jafarov, EE; Jandt, R; Johnstone, JF; Karlsson, J; Kasischke, ES; Kattner, G; Kelly, R; Keuper, F; Kling, GW; Kortelainen, P; Kouki, J; Kuhry, P; Laudon, H; Laurion, I; MacDonald, RW; Mann, PJ; Martikainen, PJ; McClelland, JW; Molau, U; Oberbauer, SF; Olefeldt, D; Paré, D; Parisien, MA; Payette, S; Peng, C; Pokrovsky, OS; Rastetter, EB; Raymond, PA; Raynolds, MK; Rein, G; Reynolds, JF; Robards, M; Rogers, BM; Schdel, C; Schaefer, K; Schmidt, IK; Shvidenko, A; Sky, J; Spencer, RGM; Starr, G; Striegl, RG; Teisserenc, R; Tranvik, LJ; Virtanen, T; Welker, JM; Zimov, S
As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%-85% of permafrost carbon release can still be avoided if human emissions are actively reduced.
Open Access
Boom and bust carbon-nitrogen dynamics during reforestation
(Ecological Modelling, 2017-09-24) Parolari, AJ; Mobley, ML; Bacon, AR; Katul, GG; Richter, DDB; Porporato, A
© 2017 Elsevier B.V. Legacies of historical land use strongly shape contemporary ecosystem dynamics. In old-field secondary forests, tree growth embodies a legacy of soil changes affected by previous cultivation. Three patterns of biomass accumulation during reforestation have been hypothesized previously, including monotonic to steady state, non-monotonic with a single peak then decay to steady state, and multiple oscillations around the steady state. In this paper, the conditions leading to the emergence of these patterns is analyzed. Using observations and models, we demonstrate that divergent reforestation patterns can be explained by contrasting time-scales in ecosystem carbon-nitrogen cycles that are influenced by land use legacies. Model analyses characterize non-monotonic plant-soil trajectories as either single peaks or multiple oscillations during an initial transient phase controlled by soil carbon-nitrogen conditions at the time of planting. Oscillations in plant and soil pools appear in modeled systems with rapid tree growth and low initial soil nitrogen, which stimulate nitrogen competition between trees and decomposers and lead the forest into a state of acute nitrogen deficiency. High initial soil nitrogen dampens oscillations, but enhances the magnitude of the tree biomass peak. These model results are supported by data derived from the long-running Calhoun Long-Term Soil-Ecosystem Experiment from 1957 to 2007. Observed carbon and nitrogen pools reveal distinct tree growth and decay phases, coincident with soil nitrogen depletion and partial re-accumulation. Further, contemporary tree biomass loss decreases with the legacy soil C:N ratio. These results support the idea that non-monotonic reforestation trajectories may result from initial transients in the plant-soil system affected by initial conditions derived from soil changes associated with land-use history.
Open Access
Changes in evapotranspiration and phenology as consequences of shrub removal in dry forests of central Argentina
(Ecohydrology, 2015-10-01) Marchesini, VA; Fernández, RJ; Reynolds, JF; Sobrino, JA; Di Bella, CM
More than half of the dry woodlands (forests and shrublands) of the world are in South America, mainly in Brazil and Argentina, where in the last years intense land use changes have occurred. This study evaluated how the transition from woody-dominated to grass-dominated system affected key ecohydrological variables and biophysical processes over 20000ha of dry forest in central Argentina. We used a simplified surface energy balance model together with moderate-resolution imaging spectroradiometer-normalized difference vegetation index data to analyse changes in above primary productivity, phenology, actual evapotranspiration, albedo and land surface temperature for four complete growing seasons (2004-2009). The removal of woody vegetation decreased aboveground primary productivity by 15-21%, with an effect that lasted at least 4years, shortened the growing season between 1 and 3months and reduced evapotranspiration by as much as 30%. Albedo and land surface temperature increased significantly after the woody to grassland conversion. Our findings highlight the role of woody vegetation in regulating water dynamics and ecosystem phenology and show how changes in vegetative cover can influence regional climatic change. © 2015 John Wiley
Open Access
Climate and health impacts of US emissions reductions consistent with 2 °C
(Nature Climate Change, 2016-05) Shindell, DT; Lee, Y; Faluvegi, G
© 2016 Macmillan Publishers Limited. All rights reserved. An emissions trajectory for the US consistent with 2 °C warming would require marked societal changes, making it crucial to understand the associated benefits. Previous studies have examined technological potentials and implementation costs and public health benefits have been quantified for less-aggressive potential emissions-reduction policies (for example, refs,), but researchers have not yet fully explored the multiple benefits of reductions consistent with 2 °C. We examine the impacts of such highly ambitious scenarios for clean energy and vehicles. US transportation emissions reductions avoid ∼0.03 °C global warming in 2030 (0.15 °C in 2100), whereas energy emissions reductions avoid ∼0.05-0.07 °C 2030 warming (∼0.25 °C in 2100). Nationally, however, clean energy policies produce climate disbenefits including warmer summers (although these would be eliminated by the remote effects of similar policies if they were undertaken elsewhere). The policies also greatly reduce damaging ambient particulate matter and ozone. By 2030, clean energy policies could prevent ∼175,000 premature deaths, with ∼22,000 (11,000-96,000; 95% confidence) fewer annually thereafter, whereas clean transportation could prevent ∼120,000 premature deaths and ∼14,000 (9,000-52,000) annually thereafter. Near-term national benefits are valued at ∼US$250 billion (140 billion to 1,050 billion) per year, which is likely to exceed implementation costs. Including longer-term, worldwide climate impacts, benefits roughly quintuple, becoming ∼5-10 times larger than estimated implementation costs. Achieving the benefits, however, would require both larger and broader emissions reductions than those in current legislation or regulations.
Open Access
Climate change challenges the current conservation strategy for the giant panda
(Biological Conservation, 2015-10-01) Shen, Guozhen; Pimm, Stuart L; Feng, Chaoyang; Ren, Guofang; Liu, Yanping; Xu, Wenting; Li, Junqing; Si, Xingfeng; Xie, Zongqiang
The global total of protected areas to conserve biodiversity is increasing steadily, while numerous studies show that they are broadly effective. That said, how will current conservation strategies work, given the current and expected changes to the global climate? The giant panda is a conservation icon and exceptional efforts protect its remaining habitats. It provides a unique case study to address this question. There are many studies on the projected loss of habitats as climate warms, but few consider the geographical arrangement of future habitats, current protected area, and species' dispersal abilities. Most alarmingly, we expect much greater habitat fragmentation after climate change. Here, we combine long-term data on giant pandas with climate-change scenarios to predict future habitat loss and distribution in the Min Shan of Sichuan and Gansu, China. We employ metapopulation capacity as a mechanistic measure of a species' response to habitat fragmentation. The results show that climate changes will lead to 16.3. ±. 1.4 (%) losses of giant panda habitats. Alarmingly, 11.4% of the remaining habitat fragments would be smaller than the extinction threshold area as the extent of fragmentation increases nearly fourfold. The projected fragmentation of giant panda habitats predicts 9% lower effectiveness inside the protected area network compared with that outside of reserves. A 35% reduction will occur in future effectiveness of reserve networks. The results challenge the long-term effectiveness of protected areas in protecting the species' persistence. They indicate a need for integrating both natural processes and dynamic threats over a simple reliance on individual static natural reserves.
Open Access
Climate science strategy of the US National Marine Fisheries Service
(Marine Policy, 2016-12) Sykora-Bodie, Seth; Busch, D Shallin; Griffis, Roger; Link, Jason; Abrams, Karen; Baker, Jason; Brainard, Russell E; Ford, Michael; Hare, Jonathan A; Himes-Cornell, Amber; Hollowed, Anne; Mantua, Nathan J; McClatchie, Sam; McClure, Michelle; Nelson, Mark W; Osgood, Kenric; Peterson, Jay O; Rust, Michael; Saba, Vincent; Sigler, Michael F; Toole, Christopher; Thunberg, Eric; Waples, Robin S; Merrick, Richard
Open Access
Climatic and Resource Determinants of Forest Elephant Movements
(Frontiers in Ecology and Evolution, 2020-04-17) Beirne, C; Meier, AC; Brumagin, G; Jasperse-Sjolander, L; Lewis, M; Masseloux, J; Myers, K; Fay, M; Okouyi, J; White, LJT; Poulsen, JR
As a keystone megafaunal species, African forest elephants (Loxodonta cyclotis) influence the structure and composition of tropical forests. Determining the links between food resources, environmental conditions and elephant movement behavior is crucial to understanding their habitat requirements and their effects on the ecosystem, particularly in the face of poaching and global change. We investigate whether fruit abundance or climate most strongly influence forest elephant movement behavior at the landscape scale in Gabon. Trained teams of “elephant trackers” performed daily fruit availability and dietary composition surveys over a year within two relatively pristine and intact protected areas. With data from 100 in-depth field follows of 28 satellite-collared elephants and remotely sensed environmental layers, we use linear mixed-effects models to assess the effects of sites, seasons, focal elephant identification, elephant diet, and fruit availability on elephant movement behavior at monthly and 3-day time scales. At the month-level, rainfall, and to a lesser extent fruit availability, most strongly predicted the proportion of time elephants spent in long, directionally persistent movements. Thus, even elephants in moist tropical rainforests show seasonal behavioral phenotypes linked to rainfall. At the follow-level (2–4 day intervals), relative support for both rainfall and fruit availability decreased markedly, suggesting that at finer spatial scales forest elephants make foraging decisions largely based on other factors not directly assessed here. Focal elephant identity explained the majority of the variance in the data, and there was strong support for interindividual variation in behavioral responses to rainfall. Taken together, this highlights the importance of approaches which follow individuals through space and time. The links between climate, resource availability and movement behavior provide important insights into the behavioral ecology of forest elephants that can contribute to understanding their role as seed dispersers, improving management of populations, and informing development of solutions to human-elephant conflict.
Open Access
Comparing Stakeholder Perceptions With Empirical Outcomes From Negotiated Rulemaking Policies: Is Participant Satisfaction a Proxy for Policy Success?
(Marine Policy, 2016) Roady, S; McDonald, S; Lewison, R; Kramer, R; Rigling-Gallagher, D; Read, A
Evaluation of natural resource management policies often is made difficult by lack of robust or long-term data on the resource. In the absence of empirical data, natural resource policy evaluation may rely on expert or stakeholder perception of success as a proxy, particularly in the context of policies that depend on multi-stakeholder engagement or negotiated rulemaking. However, few formal evaluations have compared empirical ecological outcomes with stakeholder perception. This study compares stakeholder perceptions of policy outcomes with ecological outcomes from a long-term, ecological dataset as part of the U.S. Marine Mammal Protection Act's Take Reduction Planning process. Structural Equation Models revealed that stakeholder perceptions were significantly and positively related to positive ecological outcomes. Also, perceived success and ecological performance rankings of the Take Reduction Plans were comparable for three of the five plans examined. This analysis suggests that for this particular policy instrument, stakeholder perception aligns well with ecological outcomes, and this positive relationship is likely the result of a commitment and support for stakeholder education and engagement. However, even within a single policy analysis, there was variability suggesting that the relationship between stakeholder perceptions and policy outcomes must continue to be evaluated. This study suggests that stakeholder perception can be an accurate reflection of ecological outcomes, but not necessarily a predictor of them.
Open Access
Conceptualizing and operationalizing human wellbeing for ecosystem assessment and management
(Environmental Science and Policy, 2016-12-01) Breslow, SJ; Sojka, B; Barnea, R; Basurto, X; Carothers, C; Charnley, S; Coulthard, S; Dolšak, N; Donatuto, J; García-Quijano, C; Hicks, CC; Levine, A; Mascia, MB; Norman, K; Poe, M; Satterfield, T; Martin, KS; Levin, PS
© 2016 Elsevier Ltd There is growing interest in assessing the effects of changing environmental conditions and management actions on human wellbeing. A challenge is to translate social science expertise regarding these relationships into terms usable by environmental scientists, policymakers, and managers. Here, we present a comprehensive, structured, and transparent conceptual framework of human wellbeing designed to guide the development of indicators and a complementary social science research agenda for ecosystem-based management. Our framework grew out of an effort to develop social indicators for an integrated ecosystem assessment (IEA) of the California Current large marine ecosystem. Drawing from scholarship in international development, anthropology, geography, and political science, we define human wellbeing as a state of being with others and the environment, which arises when human needs are met, when individuals and communities can act meaningfully to pursue their goals, and when individuals and communities enjoy a satisfactory quality of life. We propose four major social science-based constituents of wellbeing: connections, capabilities, conditions, and cross-cutting domains. The latter includes the domains of equity and justice, security, resilience, and sustainability, which may be assessed through cross-cutting analyses of other constituents. We outline a process for identifying policy-relevant attributes of wellbeing that can guide ecosystem assessments. To operationalize the framework, we provide a detailed table of attributes and a large database of available indicators, which may be used to develop measures suited to a variety of management needs and social goals. Finally, we discuss four guidelines for operationalizing human wellbeing measures in ecosystem assessments, including considerations for context, feasibility, indicators and research, and social difference. Developed for the U.S. west coast, the framework may be adapted for other regions, management needs, and scales with appropriate modifications.
Open Access
Contribution of Subsidies and Participatory Governance to Fishers’ Adaptive Capacity
(Journal of Environment and Development, 2016-12-01) Nenadović, M; Basurto, X; Weaver, AH
© 2016, © The Author(s) 2016. The need for strengthening fishers' adaptive capacity has been proposed in the literature as an important component of effective fisheries governance arrangements in the presence of rising numbers of external drivers of change. Within the context of small-scale fisheries, government subsidies have been the main tool used for increasing adaptive capacity. We examine the relationship among adaptive capacity, subsidy programs, and fishers' participation in fisheries management, as a potentially important mediating factor affecting outcomes using a data set from two periods of a fishing community in Baja California Sur, Mexico. Our results show a correlation between those fishers with access to decision-making venues and their reception of subsidies, yet the effect of participation and subsidies on fishers' adaptive capacity is limited. This appears to be due to the authorities' lack of commitment to strengthening fishers' adaptive capacity through subsidies programs, and fishers' lack of trust in the governance processes.
Open Access
Convergent evolution in lemur environmental niches
(Journal of Biogeography, 2020-04-01) Herrera, JP
Aim: To test the hypothesis that adaptive convergent evolution of climate niches occurred in multiple independent lemur lineages. Location: Madagascar. Taxon: Lemurs. Methods: I collected climate and altitude data from WorldClim and summarized the niches of almost all living lemurs (83 species) into phylogenetically controlled principal components. To test for convergent evolution, I searched for multiple, similar climate optima using multi-peak Ornstein–Uhlenbeck models (surface, l1-ou, bayou). I compared the observed level of climate convergence to that simulated under neutral and single-optimum models. To test if behavioural or morphological traits were related to climate niches, I used phylogenetic regressions with activity pattern, diet, and body size. Results: From an ancestral niche with high rainfall and low seasonality, four lemur lineages independently converged on climate niche optima characterized by high temperatures and low rainfall, supporting adaptive evolution in southwest deciduous and arid habitats. The observed level of convergence was more frequent than expected under Brownian motion and single-optimum simulations, which illustrates that the results are likely not a result of stochastic evolution over long time periods. Nocturnal and cathemeral activity patterns were common among lineages in the arid climate niche. Conclusion: Lemur climate niche evolution demonstrated that convergence explains the distribution of four independent clades in hot, arid environments of southwest Madagascar. The timing of these convergent shifts coincided with the origination of modern arid-adapted plant genera, some of which are important lemur food sources. These communities have high endemicity and are especially threatened by habitat loss. Arid environments are arenas in which convergent evolution is predicted to occur frequently.
Open Access
Creating linked datasets for SME energy-assessment evidence-building: Results from the U.S. Industrial Assessment Center Program
(Energy Policy, 2017-12-01) Dalzell, NM; Boyd, GA; Reiter, JP
© 2017 Elsevier Ltd Lack of information is commonly cited as a market failure resulting in an energy-efficiency gap. Government information policies to fill this gap may enable improvements in energy efficiency and social welfare because of the externalities of energy use. The U.S. Department of Energy Industrial Assessment Center (IAC) program is one such policy intervention, providing no-cost assessments to small and medium enterprises (SME). The IAC program has assembled a wealth of data on these assessments, but the database does not include information about participants after the assessment or on non-participants. This study addresses that lack by creating a new linked dataset using the public IAC and non-public data at the Census Bureau. The IAC database excludes detail needed for an exact match, so the study developed a linking methodology to account for uncertainty in the matching process. Based on the linking approach, a difference in difference analysis for SME that received an assessment was done; plants that received an assessment improve their performance over time, relative to industry peers that did not. This new linked dataset is likely to shed even more light on the impact of the IAC and similar programs in advancing energy efficiency.
Open Access
Defaunation of large mammals alters understory vegetation and functional importance of invertebrates in an Afrotropical forest
(Biological Conservation, 2020-01-01) Lamperty, Therese; Zhu, Kai; Poulsen, John R; Dunham, Amy E
Hunting has reduced or eliminated large-bodied vertebrates in many areas across the tropics, contributing to the global process of defaunation. Elucidating the ecological consequences of hunting has important implications for managing ecosystems and for our understanding of community and ecosystem ecology. We present data collected through a combination of comparative and experimental approaches to assess how faunally-intact and heavily-hunted forests in Gabon differ in understory vegetation structure, macroinvertebrate fauna, ecological processes, and the relative importance of different taxa driving those processes. Our results show that hunted sites had denser understory vegetation and hosted approximately 170 times fewer termites compared to faunally-intact sites. While web-building spiders were positively associated with understory vegetation density, this effect did not translate to significantly higher abundances in heavily-hunted forests. Additionally, the overall rates of decomposition, insectivory, and seed predation/removal on the forest floor appeared robust to both defaunation and the associated increases in understory vegetation density. However, our exclosure experiments revealed that the contribution of invertebrates to decomposition was approximately 25% lower in hunted sites compared to faunally-intact sites. Results suggest potential resilience in this complex ecosystem such that microbial or other taxa not measured in this study may compensate for the reduced functional contribution of invertebrates to decomposition. However, while our results illustrate potential resilience, they also indicate that indirect effects following defaunation, such as increases in the density of understory vegetation, may alter invertebrate communities on the forest floor, with potential consequences for the mechanisms, and therefore the dynamics, driving critical ecosystem processes.
Open Access
Defining Small-Scale Fisheries and Examining the Role of Science in Shaping Perceptions of Who and What Counts: A Systematic Review
(Frontiers in Marine Science, 2019-05-07) Smith, H; Basurto, X
Open Access
Deforestation risks posed by oil palm expansion in the Peruvian Amazon
(Environmental Research Letters, 2018-11-01) Vijay, V; Reid, CD; Finer, M; Jenkins, CN; Pimm, SL
Further expansion of agriculture in the tropics is likely to accelerate the loss of biodiversity. One crop of concern to conservation is African oil palm (Elaeis guineensis). We examined recent deforestation associated with oil palm in the Peruvian Amazon within the context of the region's other crops. We found more area under oil palm cultivation (845 km2) than did previous studies. While this comprises less than 4% of the cropland in the region, it accounted for 11% of the deforestation from agricultural expansion from 2007-2013. Patches of oil palm agriculture were larger and more spatially clustered than for other crops, potentially increasing their impact on local habitat fragmentation. Modeling deforestation risk for oil palm expansion using climatic and edaphic factors showed that sites at lower elevations, with higher precipitation, and lower slopes than those typically used for intensive agriculture are at long-term risk of deforestation from oil palm agriculture. Within areas at long-term risks, based on CART models, areas near urban centers, roads, and previously deforested areas are at greatest short-term risk of deforestation. Existing protected areas and officially recognized indigenous territories cover large areas at long-term risk of deforestation for oil palm (>40%). Less than 7% of these areas are under strict (IUCN I-IV) protection. Based on these findings, we suggest targeted monitoring for oil palm deforestation as well as strengthening and expanding protected areas to conserve specific habitats.
Open Access
Describing the diversity of community supported fishery programs in North America
(Marine Policy, 2016-04-01) Bolton, AE; Dubik, BA; Stoll, JS; Basurto, X
© 2016 Elsevier Ltd. This research investigates organizational diversity within Community Supported Fisheries (CSFs) in North America. Generally understood as the direct marketing of seafood through pre-arranged deliveries, CSFs have increased in number and geographic distribution since their origin in 2007. Despite, or because of, this rapid growth, fundamental questions remain unanswered about what organizational structures and business practices currently constitute the term 'CSF'. This research draws on interview data from 22 CSFs to highlight the diversity within the CSF movement and inform ongoing debates about appropriate paths for their continued growth. Interview data is used to describe key areas of convergence and divergence among the goals, business practices, and structures of CSFs. Three general types of CSF are identified based on this analysis: harvester focused, consumer focused and species focused. Each type is described through a short illustrative case study. Overall results indicate that the term 'CSF' does not currently refer to a specific structure or type of organization, but rather an approach to seafood marketing used by a variety of organizations with broadly similar production philosophies centered on engaging and informing consumers around traceable, domestically sourced seafood. Acknowledgment of CSFs as diverse and socially embedded organizations is necessary to understanding their potential benefits.
Open Access
Diet of red-legged sun squirrels (Heliosciurus rufobrachium Waterhouse) in Kibale National Park, Uganda: Implications for seed defence
(African Journal of Ecology, 2019-01-01) Struhsaker, TT
Open Access
DNA barcoding exposes a case of mistaken identity in the fern horticultural trade.
(Molecular ecology resources, 2010-11) Pryer, Kathleen M; Schuettpelz, Eric; Huiet, Layne; Grusz, Amanda L; Rothfels, Carl J; Avent, Tony; Schwartz, David; Windham, Michael D
Using cheilanthoid ferns, we provide an example of how DNA barcoding approaches can be useful to the horticultural community for keeping plants in the trade accurately identified. We use plastid rbcL, atpA, and trnG-R sequence data to demonstrate that a fern marketed as Cheilanthes wrightii (endemic to the southwestern USA and northern Mexico) in the horticultural trade is, in fact, Cheilanthes distans (endemic to Australia and adjacent islands). Public and private (accessible with permission) databases contain a wealth of DNA sequence data that are linked to vouchered plant material. These data have uses beyond those for which they were originally generated, and they provide an important resource for fostering collaborations between the academic and horticultural communities. We strongly advocate the barcoding approach as a valuable new technology available to the horticulture industry to help correct plant identification errors in the international trade.

Browsing by Subject "Environmental Sciences & Ecology"

Results Per Page

Sort Options