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  • 1
    In: Remote Sensing in Ecology and Conservation, Wiley, Vol. 8, No. 1 ( 2022-02), p. 57-71
    Abstract: Non‐forest ecosystems, dominated by shrubs, grasses and herbaceous plants, provide ecosystem services including carbon sequestration and forage for grazing, and are highly sensitive to climatic changes. Yet these ecosystems are poorly represented in remotely sensed biomass products and are undersampled by in situ monitoring. Current global change threats emphasize the need for new tools to capture biomass change in non‐forest ecosystems at appropriate scales. Here we developed and deployed a new protocol for photogrammetric height using unoccupied aerial vehicle (UAV) images to test its capability for delivering standardized measurements of biomass across a globally distributed field experiment. We assessed whether canopy height inferred from UAV photogrammetry allows the prediction of aboveground biomass (AGB) across low‐stature plant species by conducting 38 photogrammetric surveys over 741 harvested plots to sample 50 species. We found mean canopy height was strongly predictive of AGB across species, with a median adjusted R 2 of 0.87 (ranging from 0.46 to 0.99) and median prediction error from leave‐one‐out cross‐validation of 3.9%. Biomass per‐unit‐of‐height was similar within but different among, plant functional types. We found that photogrammetric reconstructions of canopy height were sensitive to wind speed but not sun elevation during surveys. We demonstrated that our photogrammetric approach produced generalizable measurements across growth forms and environmental settings and yielded accuracies as good as those obtained from in situ approaches. We demonstrate that using a standardized approach for UAV photogrammetry can deliver accurate AGB estimates across a wide range of dynamic and heterogeneous ecosystems. Many academic and land management institutions have the technical capacity to deploy these approaches over extents of 1–10 ha −1 . Photogrammetric approaches could provide much‐needed information required to calibrate and validate the vegetation models and satellite‐derived biomass products that are essential to understand vulnerable and understudied non‐forested ecosystems around the globe.
    Type of Medium: Online Resource
    ISSN: 2056-3485 , 2056-3485
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2022
    detail.hit.zdb_id: 2825232-9
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  • 2
    In: The Lancet, Elsevier BV, Vol. 380, No. 9840 ( 2012-08), p. 507-535
    Type of Medium: Online Resource
    ISSN: 0140-6736
    RVK:
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2012
    detail.hit.zdb_id: 2067452-1
    detail.hit.zdb_id: 3306-6
    detail.hit.zdb_id: 1476593-7
    SSG: 5,21
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  • 3
    In: The Journal of Allergy and Clinical Immunology: In Practice, Elsevier BV, Vol. 11, No. 7 ( 2023-07), p. 2043-2048
    Type of Medium: Online Resource
    ISSN: 2213-2198
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2023
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  • 4
    In: River Research and Applications, Wiley, Vol. 37, No. 3 ( 2021-03), p. 343-357
    Abstract: Eurasian beavers, keystone species, have returned to inhabit much of its former range following near extinction. Evidence repeatedly demonstrates that beavers can provide important riparian biotic and abiotic ecosystem services. These abilities to modify their surroundings can cause conflict, especially in prime agricultural landscapes. Understanding how beavers are utilizing and expanding in European catchments is therefore essential. This paper presents a methodology by which the spatial extent and environmental impact of beavers can be quantified via distinctive field signs. This has widespread application in understanding their distribution, expansion, and any management implications. Its application is tested within two diverse case studies, the Tayside catchment, Scotland, and the Wye catchment, Wales/England, collectively covering 〉 10,000 km 2 of catchment area. A minimum of 114 active territories were identified in Tayside and a small number of free‐roaming beavers with no strong evidence of breeding territories were recorded on the River Wye. This study demonstrates that a detailed, time and cost efficient but also easily replicable, field survey method can allow estimates of beaver territorial zones when combined with geospatial analysis and expert assessment. As populations of Eurasian beavers continue to expand and be actively reintroduced across Europe, this survey‐based approach can be utilized to increase understanding of their distribution, population dynamics, and territorial behavior, as well as informing management strategies and identifying areas of potential benefit and/or conflict.
    Type of Medium: Online Resource
    ISSN: 1535-1459 , 1535-1467
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 2074114-5
    SSG: 12
    SSG: 14
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  • 5
    In: British Journal of Pharmacology, Wiley, Vol. 106, No. 1 ( 1992-05), p. 199-207
    Type of Medium: Online Resource
    ISSN: 0007-1188
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 1992
    detail.hit.zdb_id: 2029728-2
    SSG: 15,3
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  • 6
    Online Resource
    Online Resource
    Wiley ; 2018
    In:  Earth Surface Processes and Landforms Vol. 43, No. 11 ( 2018-09-15), p. 2358-2370
    In: Earth Surface Processes and Landforms, Wiley, Vol. 43, No. 11 ( 2018-09-15), p. 2358-2370
    Abstract: Beavers, primarily through the building of dams, can deliver significant geomorphic modifications and result in changes to nutrient and sediment fluxes. Research is required to understand the implications and possible benefits of widespread beaver reintroduction across Europe. This study surveyed sediment depth, extent and carbon/nitrogen content in a sequence of beaver pond and dam structures in South West England, where a pair of Eurasian beavers ( Castor fiber ) were introduced to a controlled 1.8 ha site in 2011. Results showed that the 13 beaver ponds subsequently created hold a total of 101.53 ± 16.24 t of sediment, equating to a normalised average of 71.40 ± 39.65 kg m 2 . The ponds also hold 15.90 ± 2.50 t of carbon and 0.91 ± 0.15 t of nitrogen within the accumulated pond sediment. The size of beaver pond appeared to be the main control over sediment storage, with larger ponds holding a greater mass of sediment per unit area. Furthermore, position within the site appeared to play a role with the upper‐middle ponds, nearest to the intensively‐farmed headwaters of the catchment, holding a greater amount of sediment. Carbon and nitrogen concentrations in ponds showed no clear trends, but were significantly higher than in stream bed sediment upstream of the site. We estimate that 〉 70% of sediment in the ponds is sourced from the intensively managed grassland catchment upstream, with the remainder from in situ redistribution by beaver activity. While further research is required into the long‐term storage and nutrient cycling within beaver ponds, results indicate that beaver ponds may help to mitigate the negative off‐site impacts of accelerated soil erosion and diffuse pollution from agriculturally dominated landscapes such as the intensively managed grassland in this study. © 2018 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd.
    Type of Medium: Online Resource
    ISSN: 0197-9337 , 1096-9837
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2018
    detail.hit.zdb_id: 1479188-2
    SSG: 14
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  • 7
    Online Resource
    Online Resource
    Wiley ; 2021
    In:  Hydrological Processes Vol. 35, No. 2 ( 2021-02)
    In: Hydrological Processes, Wiley, Vol. 35, No. 2 ( 2021-02)
    Abstract: Beavers can profoundly alter riparian environments, most conspicuously by creating dams and wetlands. Eurasian beaver ( Castor fiber ) populations are increasing and it has been suggested they could play a role in the provision of multiple ecosystem services, including natural flood management. Research at different scales, in contrasting ecosystems is required to establish to what extent beavers can impact on flood regimes. Therefore, this study determines whether flow regimes and flow responses to storm events were altered following the building of beaver dams and whether a flow attenuation effect could be significantly attributed to beaver activity. Four sites were monitored where beavers have been reintroduced in England. Continuous monitoring of hydrology, before and after beaver impacts, was undertaken on streams where beavers built sequences of dams. Stream orders ranged from 2nd to 4th, in both agricultural and forest‐dominated catchments. Analysis of 〉 1000 storm events, across four sites showed an overall trend of reduced total stormflow, increased peak rainfall to peak flow lag times and reduced peak flows, all suggesting flow attenuation, following beaver impacts. Additionally, reduced high flow to low flow ratios indicated that flow regimes were overall becoming less “flashy” following beaver reintroduction. Statistical analysis, showed the effect of beaver to be statistically significant in reducing peak flows with estimated overall reductions in peak flows from −0.359 to −0.065 m 3 s −1 across sites. Analysis showed spatial and temporal variability in the hydrological response to beaver between sites, depending on the level of impact and seasonality. Critically, the effect of beavers in reducing peak flows persists for the largest storms monitored, showing that even in wet conditions, beaver dams can attenuate average flood flows by up to ca. 60%. This research indicates that beavers could play a role in delivering natural flood management.
    Type of Medium: Online Resource
    ISSN: 0885-6087 , 1099-1085
    URL: Issue
    Language: English
    Publisher: Wiley
    Publication Date: 2021
    detail.hit.zdb_id: 1479953-4
    SSG: 14
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  • 8
    Online Resource
    Online Resource
    Cambridge University Press (CUP) ; 1987
    In:  Journal of Dairy Research Vol. 54, No. 2 ( 1987-05), p. 219-235
    In: Journal of Dairy Research, Cambridge University Press (CUP), Vol. 54, No. 2 ( 1987-05), p. 219-235
    Abstract: Skim milk samples from 126 Friesian and 147 Jersey cows in eight commercial herds were preheated at 85 °C for 30 min and concentrated to 200 g l −1 total solids. A heat coagulation time–pH curve was determined at 120 °C for each treated sample. Heat coagulation times ranged from 1 to 50 min at the non-adjusted pH and 1 to 60 min at the pH of maximum stability. The following statistically significant effects were found. Maximum heat stability was affected by genetic variants of κ-casein (B 〉 AB 〉 A; P 〈 0·001) and β-lactoglobulin (B, AB 〉 A; P 〈 0·05) whereas natural heat stability was affected only by κ-casein genetic variants (B 〉 AB 〉 A; P 〈 0·001). Maximum and natural heat stability were corre-lated positively with β-casein and κ-casein concentrations and were negatively correlated with α s1 -casein and β-lactoglobulin concentrations. Milk from Jersey cows had greater maximum and natural heat stability than milk from Friesian cows. Differences were found between herds within breed for natural heat stability, but not for maximum heat stability. Maximum heat stability declined with age of the cow. The heat stability of skim milk samples taken from 40 Jersey cows in one of the herds was determined at 140 °C. A considerable variation was found in the coagulation time–pH curves. There was a difference in natural heat stability between κ-casein variants (B 〉 AB; P 〈 0°05). Natural and maximum heat stability were correlated positively with urea concentration. No relationship was found between the heat stability of preheated concentrated skim milk and the heat stability of the original skim milk. The pH of skim milk samples was associated with α s1 -casein genetic variant, age of cow, stage of lactation and concentration of γ-casein.
    Type of Medium: Online Resource
    ISSN: 0022-0299 , 1469-7629
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 1987
    detail.hit.zdb_id: 2000010-8
    SSG: 22
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  • 9
    Online Resource
    Online Resource
    Informa UK Limited ; 2003
    In:  Emu - Austral Ornithology Vol. 103, No. 3 ( 2003-09), p. 255-258
    In: Emu - Austral Ornithology, Informa UK Limited, Vol. 103, No. 3 ( 2003-09), p. 255-258
    Type of Medium: Online Resource
    ISSN: 0158-4197 , 1448-5540
    Language: English
    Publisher: Informa UK Limited
    Publication Date: 2003
    detail.hit.zdb_id: 2045165-9
    SSG: 12
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  • 10
    Online Resource
    Online Resource
    Cambridge University Press (CUP) ; 2011
    In:  Bird Conservation International Vol. 21, No. 2 ( 2011-06), p. 207-220
    In: Bird Conservation International, Cambridge University Press (CUP), Vol. 21, No. 2 ( 2011-06), p. 207-220
    Abstract: The population growth of Brown Kiwi Apteryx mantelli was measured under four different management regimes: unmanaged, predator trapping, predator poisoning, and Bank of New Zealand Operation Nest Egg™ (BNZONE) — the removal of eggs for artificial incubation and return of resultant subadults to the wild. Life table analysis revealed that high adult mortality (7.3% per annum), caused mainly by domestic dog Canis familiaris and Ferret Mustela furo predation was the critical factor affecting Brown Kiwi populations in central Northland. The 13.8-year life expectancy of adults was only one-third of what can be expected in the absence of these two predators. Predation of Brown Kiwi chicks and juveniles ( 〈 1 kg) by Stoats Mustela erminea and, to a lesser extent, domestic cats Felis catus , was also important. Unmanaged populations declined at 2.5% per annum. Trapping pests in a 200 ha area was largely ineffective, with the population declining by 1.7% per annum. Poisoning pests allowed Brown Kiwi populations to increase at 3.3% per annum. BNZONE proved to be by far the most effective tool, resulting in a 12.5% annual population increase, mainly due to 83% chick survival to six months old, compared with 10% survival in unmanaged sites. There were no observable behavioural problems associated with chicks being reared ex situ , but BNZONE was the most expensive tool and benefited only the Brown Kiwi. This study has helped to develop a range of tools that are now being used to facilitate recovery of populations of all four threatened species of kiwi in New Zealand, and the experimental approach used has wider application in management of other threatened species.
    Type of Medium: Online Resource
    ISSN: 0959-2709 , 1474-0001
    Language: English
    Publisher: Cambridge University Press (CUP)
    Publication Date: 2011
    detail.hit.zdb_id: 2037673-X
    SSG: 12
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