272 research outputs found
River ecosystem metabolism modelling outputs (Lachlan River, NSW, 2018-07-01 to 2019-06-30)
No full textThe purpose of the modelling was to 1) build knowledge around how river flow and connectivity affect aquatic ecosystem metabolism, and 2) provide a robust case study for scaling flow-ecology responses to larger spatial scales (i.e., an entire catchment). This data collection contains the predicted rates of ecosystem metabolism (gross primary production and ecosystem respiration) at unmonitored locations on the Lachlan River, NSW, Australia.\nLineage: These data were produced using a spatio-temporal modelling framework. Rates of gross primary production (GPP) and ecosystem respiration (ER) were modelled as a function of monthly air temperature, monthly solar exposure, discharge magnitude, and discharge temporal variability. These variables, together with estimated spatial and temporal dependencies, were subsequently used to estimate GPP and ER at unmonitored locations along the Lachlan River.\n\nFull details available in Giling et al. Season and Flow Drive Productivity of a Regulated River (2025) Ecosystems. In press
Mapping change in biodiversity and ecosystem function research: food webs foster integration of experiments and science policy
No full textHuman activities are causing major changes in biological communities worldwide. Due to concern about the consequences of these changes, an academic conversation about biodiversity and ecosystem functioning (BEF) has emerged over the last few decades. Here we use a keyword co-occurrence analysis to characterize and review 28 years of research focused on these terms. We find that the rapidly growing literature has developed in four research domains. The first two domains “BEF Experiments” and “Science Policy” emerge early, and persist through time, as core research areas with emphases on experiments and management, respectively. The second two domains, “Agricultural Landscapes” and “Aquatic Food Webs”, arise as integrative domains that connect divisions in scientific discussion surrounding BEF Experiments and Science Policy. Terms related to species interactions (i.e. pollinator, predator, food web) appear more commonly in the two integrative domains reflecting shared interests of many scientists focusing on biodiversity and ecosystem functioning. Despite shared interests in food webs, research in the four domains differ with respect to their spatial scale, baseline comparisons, and currency of measurements. Food-web research that bridges these divides should be pushed to the forefront of biodiversity and ecosystem functioning research priorities
A cross‐scale assessment of productivity–diversity relationships
Get PDFAim: Biodiversity and ecosystem productivity vary across the globe, and considerable effort has been made to describe their relationships. Biodiversity and ecosystem functioning research has traditionally focused on how experimentally controlled species richness affects net primary productivity (S → NPP) at small spatial grains. In contrast, the influence of productivity on richness (NPP → S) has been explored at many grains in naturally assembled communities. Mismatches in spatial scale between approaches have fuelled debate about the strength and direction of biodiversity–productivity relationships. Here, we examine the direction and strength of the influence of productivity on diversity (NPP → S) and the influence of diversity on productivity (S → NPP) and how these vary across spatial grains. Location: Contiguous USA. Time period: 1999–2015. Major taxa studied: Woody species (angiosperms and gymnosperms). Methods: Using data from North American forests at grains from local (672 m2) to coarse spatial units (median area = 35,677 km2), we assess relationships between diversity and productivity using structural equation and random forest models, while accounting for variation in climate, environmental heterogeneity, management and forest age. Results: We show that relationships between S and NPP strengthen with spatial grain. Within each grain, S → NPP and NPP → S have similar magnitudes, meaning that processes underlying S → NPP and NPP → S either operate simultaneously or that one of them is real and the other is an artefact. At all spatial grains, S was one of the weakest predictors of forest productivity, which was largely driven by biomass, temperature and forest management and age. Main conclusions: We conclude that spatial grain mediates relationships between biodiversity and productivity in real-world ecosystems and that results supporting predictions from each approach (NPP → S and S → NPP) serve as an impetus for future studies testing underlying mechanisms. Productivity–diversity relationships emerge at multiple spatial grains, which should widen the focus of national and global policy and research to larger spatial grains
Importance of exposure route in determining nanosilver impacts on a stream detrital processing chain
No full textThe commercial use and spread of silver nanoparticles (AgNPs) in freshwaters have greatly increased over the last decade. Both AgNPs and ionic silver (Ag+) released from nanoparticles are toxic to organisms and compromise ecosystem processes such as leaf litter decomposition. Yet little is known about how AgNPs affect multitrophic systems of interacting species. Furthermore, past work has focused on waterborne exposure with scarce attention given to effects mediated by the consumption of contaminated food. We assessed the importance of direct (via water) and indirect (via diet) AgNP exposure to a processing chain comprising leaf litter, fungi, a shredder (Gammarus pulex) and a collector (Habroleptoides confusa) in microcosms. Direct exposure to contaminated water for 15 days impaired microbial leaf decomposition by ∼50% and leaf-associated fungal biomass by ∼10%. Leaf consumption was reduced by ∼20% but only when G. pulex was exposed to silver via contaminated leaves. There was no effect on FPOM production. Ag + could impose oxidative stress on the shredders and collectors independent of exposure route, as indicated by increased catalase and glutathione S-transferase activities and decreased superoxide dismutase activity. The activity of a neuronal enzyme (cholinesterase) in collectors, but not shredders, also decreased by almost 50% when the animals were indirectly exposed to AgNP. Our results show that AgNPs and Ag+ may disrupt detrital processing chains through direct and indirect exposure routes, even at low concentrations. This highlights the importance of AgNP exposure pathways to interconnected stream biota and ecosystem processes for realistic assessments of risks to freshwater ecosystems.</p
Riparian vegetation removal alters consumer-resource stoichiometry in an Australian lowland stream
No full textAnthropogenic impacts on stream ecosystems generate changes in nutrient and carbon availability which act as stoichiometric challenges to consumers. We tested the hypothesis that removal of Eucalyptus riparian vegetation alters in-stream resource stoichiometry with flow-on effects for a benthic consumer (the freshwater crayfish, Cherax destructor). Sites with high and low riparian canopy cover were selected on a lowland stream in south-eastern Australia. A reduction in riparian vegetation canopy cover was associated with decreased terrestrial detritus (low nutritional quality; high carbon to nitrogen (C :N) ratio) and increased cover of macrophytes and filamentous algae (high quality; low C :N ratio). This resource-quality shift was associated with a small but significant decrease in C. destructor C :N ratio (molar ratio of muscle tissue). This suggests that the animals are deviating from homeostasis and may be in better condition in the stream pools dominated by in-stream productivity. A significant negative relationship between C. destructor length and C :N ratio was observed, suggesting that resource-quality impacts may differ with age. The present study has shown that riparian loss alters stoichiometric interactions in stream benthic ecosystems, with potential consequences for stream processes such as nutrient cycling. Ecological stoichiometric theory should therefore be further utilised to make predictions of ecological impacts in freshwater ystems
Visual art made musical: issues of shape, proportion and large-scale form in Escher sketches
No full textThis dissertation examines the relationship between the orchestral work, Escher Sketches, and the two graphic prints by M.C. Escher on which its music is based, Regular Division of the Plane I and Regular Division of the Plane VI. Chapter 1 provides background information on the two visual works and, generally, on Escher's work with the "regular division of the plane." Chapter 2 discusses how Escher Sketches, a 12-tone piece, utilizes a regular division of the octave in the construction of the prime row forms behind its two movements. Chapter 3 and Chapter 4 explain how Movement I, "Birds and Fish," and Movement II, "Lizards," share structural similarities with Escher's prints at the background, middleground and foreground levels of the music.Ph.D.Includes bibliographical references (p. 105)
Effect of creatine supplementation during cast-induced immobilization on the preservation of muscle mass, strength, and endurance
No full textBarriers to collaborative nature conservatioin efforts in rural energy corridors: A case study in southern Quebec
No full textxvi; ill. (some col.), maps (some col.) ; 31cm.; Note(s): Includes bibliographical references and indexes.; Responsibility: edited by John W. Goodrich-Mahoney ... [et al.] ; major sponsors, Niagara Mohawk: a national grid company ... [et al.] ; symposium co-chairmen, Lawrence P. Abrahamson, Kevin McLoughlin. Vendor Info: YBP Library Services Baker & Taylor Baker and Taylor (YANK BKTY BTCP) 250.00 Status: active; Entry: 20071114; Update: 20080829Source type: Print(0
Can regulatory takings litigation cause a chilling effect? A study of law and federal environmental regulation
No full textThe classical story of regulatory takings litigation, which demands compensation under the Fifth Amendment from regulatory agencies which restrict property use and/or development, predicts that such litigation can cause a chilling effect, or a reduction in an agency's regulatory output, to offset and/or avoid such compensatory demands. Such predictions are based on assumptions rooted in economic analyses of law and regulatory behavior. Quantitative, qualitative, theoretical, and legal analyses were conducted on takings litigation involving two federal environmental programs, the Endangered Species Act and the Surface Mining Control and Reclamation Act, to test the acceptability of such assumptions. By interpreting such litigation through the lens of legal pluralism, an anthropological approach to the study of law when multiple legal traditions exist in the same space and time, the nature of takings litigation as a dialectic and hermeneutic evolution between the constitutional codification of property rights and the common law traditions of nuisance and public welfare is revealed. Regulatory takings law is, therefore, not an economic equation determining some restrictions compensable and others not; it is a fluid body of law, heavily determined by contexts of meaning which, themselves, change over time and place. From this perspective, the perceptions of regulatory agents become central, as the likelihood of a chilling effect is dependent upon their perceptions of their own powers and responsibilities under takings jurisprudence and their enabling statutes. Interviews with such personnel revealed that any chilling effect caused by takings litigation must overcome institutional constraints which shape those agents' perceptions and awareness of takings and environmental legal rights and responsibilities. These institutions include the external and internal fragmentation of regulatory decision-making, the presence of an agency culture of enforcement, the particulars of the relationship between the regulators and the regulated, and the effect of a maintained regulatory presence of the program, shaping the perceived acceptability of property restraints necessary for successful implementation.Ph.D.Includes bibliographical references (p. 238-245)
Adjunctive treatment with oral AKL1, a botanical nutraceutical, in chronic obstructive pulmonary disease
Get PDFClaire Brockwell,1 Sundari Ampikaipakan,1,2 Darren W Sexton,1 David Price,3,4 Daryl Freeman,5 Mike Thomas,6 Muzammil Ali,4 Andrew M Wilson1,21Norwich Medical School, University of East Anglia, Norwich, UK; 2Norfolk and Norwich University Hospital Foundation Trust, Norwich, UK; 3Academic Primary Care, University of Aberdeen, Aberdeen, UK; 4Research in Real Life, Cambridge, UK; 5Mundesley Medical Centre, Mundesley, Norwich, UK; 6Primary Care Research, Aldermoor Health Centre, University of Southampton, Southampton, UKPurpose: The objective of this pilot trial was to evaluate the safety and efficacy of AKL1, a patented botanical formulation containing extracts of Picrorhiza kurroa, Ginkgo biloba, and Zingiber officinale, as add-on therapy for patients with chronic obstructive pulmonary disease (COPD) and chronic cough.Patients and methods: This randomized, double-blind, placebo-controlled trial enrolled male and female patients >18 years old with COPD and Leicester Cough Questionnaire (LCQ) score of <18. The 10-week study period comprised a 2-week single-blind placebo run-in period followed by add-on treatment with AKL1 or placebo twice daily for 8 weeks. The primary study endpoint was the change from week 0 to week 8 in cough-related health status, as assessed by the LCQ.Results: Of 33 patients enrolled, 20 were randomized to AKL1 and 13 to placebo. Patients included 19 (58%) men and 14 (42%) women of mean (standard deviation [SD]) age of 67 (9.4) years; 15 (45%) patients were smokers and 16 (49%) were ex-smokers. The mean (SD) change from baseline in LCQ score at 8 weeks was 2.3 (4.9) in the AKL1 group and 0.6 (3.7) in the placebo group, with mean difference in change of 1.8 (95% confidence interval: –1.5 to 5.1; P=0.28). The St George's Respiratory Questionnaire score improved substantially in the AKL1 treatment group by a mean (SD) of –7.7 (11.7) versus worsening in the placebo group (+1.5 [9.3]), with mean difference in change of –9.2 (95% confidence interval: –19.0 to 0.6; P=0.064). There were no significant differences between treatment groups in change from baseline to week 8 in other patient-reported measures, lung function, or the 6-minute walk distance.Conclusion: Further study is needed with a larger patient population and over a longer duration to better assess the effects of add-on therapy with AKL1 in COPD.Keywords: Leicester Cough Questionnaire, anti-inflammatory, Picrorhiza kurroa, Ginkgo biloba, Zingiber officinal
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