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- ItemThe effect of foraging and ontogeny on the prevalence and intensity of the invasive parasite Anguillicola crassus in the European eel Anguilla anguilla(Wiley, 2017-01-13) Barry, J.; Newton, M.; Dodd, J. A.; Evans, Derek; Newton, J.; Adams, C. E.Infection patterns of the invasive Anguillicola crassus nematode were investigated in a population of the European eel Anguilla anguilla where parasite invasion is very recent, Loch Lomond, Scotland. Intensity levels of the parasite were associated with differences in fish ontogeny and trophic ecology. Although eels foraged on both fish and invertebrates, individuals which were smaller and fed on invertebrates (>70% contribution to diet) were found to contain a greater number of swim bladder parasites compared to larger eel with a predominance of fish (>60% contribution) in their diet. Within affected fish, a significant negative relationship was found between fish length and parasite intensity, with smaller individuals having higher parasite intensity than larger individuals. This study indicates that food intake and infection risk are linked in this recently infected host–parasite system. From a management perspective increasing our understanding of how infection intensity and repeated exposure is linked to resource use in an ecosystem is important for the future management of this endangered species in Europe.
- ItemNitrogen dynamics and phytoplankton community structure: the role of organic nutrients(Springer, 2017-06-15) Moschonas, Grigorios; Gowen, Richard J.; Paterson, Ruth F.; Mitchell, Elaine; Stewart, Brian M.; McNeill, Sharon; Glibert, Patricia M.; Davidson, KeithDissolved organic nitrogen (DON) is recognised as an important N source for phytoplankton. However, its relative importance for phytoplankton nutrition and community composition has not been studied comprehensively. This study, conducted in a typical Scottish fjord, representative of nearpristine coastal environments, evaluates the utilisation of DON and dissolved inorganic nitrogen (DIN) by different microbial size fractions and the relationship of phytoplankton community composition with DON and other parameters. The study demonstrated that DON was important in supporting phytoplankton throughout the yearly production cycle. The higherthan-expected urea uptake rates and large fraction of the spring bloom production supported by DON suggested that organic N not only contributes to regenerated production and to the nutrition of the small phytoplankton fraction, but can also contribute substantially to new production of the larger phytoplankton in coastal waters. Multivariate statistical techniques revealed two phytoplankton assemblages with peaks in abundance at different times of the year: a spring group dominated by Skeletonema spp., Thalassiosira spp., and Pseudo-nitzschia spp. group delicatissima; and a summer/autumn group dominated by Chaetoceros spp., Scrippsiella spp., and Pseudonitzschia spp. group seriata. The multivariate pattern in community composition and abundance of these taxa was significantly correlated with the multivariate pattern of DON, urea, dissolved free amino acids, DIN, temperature, salinity, and daylength, with daylength and urea being particularly important, suggesting both physical and chemical controls on community composition.
- ItemAssessments of Composite and Discrete Sampling Approaches for Water Quality Monitoring(Springer, 2018-04-12) Cassidy, Rachel; Jordan, Phil; Bechmann, Marianne; Kronvang, Brian; Kyllmar, Katarina; Shore, MaireadAchieving an operational compromise between spatial coverage and temporal resolution in national scale river water quality monitoring is a major challenge for regulatory authorities, particularly where chemical concentrations are hydrologically dependent. The efficacy of flow-weighted composite sampling (FWCS) approaches for total phosphorus (TP) sampling (n = 26–52 analysed samples per year), previously applied in monitoring programmes in Norway, Sweden and Denmark, and which account for low to high flow discharges, was assessed by repeated simulated sampling on high resolution TP data. These data were collected in three research catchments in Ireland over the period 2010–13 covering a base-flow index range of 0.38 to 0.69. Comparisons of load estimates were also made with discrete (set time interval) daily and sub-daily sampling approaches (n = 365 to >1200 analysed samples per year). For all years and all sites a proxy of the Norwegian sampling approach, which is based on re-forecasting discharge for each 2-week deployment, proved most stable (median TP load estimates of 87–98%). Danish and Swedish approaches, using long-term flow records to set a flow constant, were only slightly less effective (median load estimates of 64–102% and 80–96%, respectively). Though TP load estimates over repeated iterations were more accurate using the discrete approaches, particularly the 24/7 approach (one sample every 7 h in a 24 bottle sampler - median % load estimates of 93–100%), composite load estimates were more stable, due to the integration of multiple small samples (n = 100–588) over a deployment.
- ItemOcean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia(Wiley, 2018-05-16) Jaspers, Cornelia; Huwer, Bastian; Antajan, Elvire; Hosia, Aino; Hinrichsen, Hans-Harald; Biastoch, Arne; Angel, Dror; Asmus, Ragnhild; Augustin, Christina; Bagher, Siamak; Beggs, Steven; Balsby, Thorsten J. S.; Boersma, Maarten; Bonnet, Delphine; Christensen, Jens T.; Dänhardt, Andreas; Delpy, Floriane; Falkenhaug, Tone; Finenko, Galina; Fleming, Nicholas E. C.; Fuentes, Veronica; Galil, Bella; Gittenberger, Arjan; Griffin, Donal C.; Haslob, Holger; Javidpou, Jamileh; Kamburska, Lyudmila; Kube, Sandra; Langenberg, Victor T.; Lehtiniemi, Maiju; Lombard, Fabien; Malzahn, Arne; Marambio, Macarena; Mihneva, Veselina; Møller, Lene Friis; Niermann, Ulrich; Okyar, Melek Isinibilir; Ozdemir, Zekiye Birinci; Pitois, Sophie; Reusch, Thorsten B. H.; Robbens, Johan; Stefanova, Kremena; Thibault, Delphine; van der Veer, Henk W.; Vansteenbrugge, Lies; van Walraven, Lodewijk; Wozniczka, AdamAim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further distribution after the initial establishment of non-native species remain largely unresolved, especially in marine systems. Ocean currents can be a major driver governing range occupancy, but this has not been accounted for in most invasion ecology studies so far. We investigate how well initial establishment areas are interconnected to later occupancy regions to test for the potential role of ocean currents driving secondary spread dynamics in order to infer invasion corridors and the source–sink dynamics of a non-native holoplanktonic biological probe species on a continental scale. Location: Western Eurasia. Time period: 1980s–2016. Major taxa studied: ‘Comb jelly’ Mnemiopsis leidyi. Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents. Additionally, genetic markers are used to test the predicted connectivity between subpopulations. Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions and the timing of first occurrence of our holoplanktonic non-native biological probe species, leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over large distances after local extinctions. Main conclusions: Although the release of ballast water from container ships may contribute to the dispersal of non-native species, our results highlight the importance of ocean currents driving secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for secondary spread dynamics on a continental scale. Invasion risk assessments should consider large-scale connectivity patterns and the potential source regions of non-native marine species.
- ItemUsing Coupled Hydrodynamic Biogeochemical Models to Predict the Effects of Tidal Turbine Arrays on Phytoplankton Dynamics(MDPI, 2018-05-22) Schuchert, Pia; Kregting, Louise; Pritchard, Daniel; Savidge, Graham; Elsasser, BjornThe effects of large scale tidal energy device (TED) arrays on phytoplankton processes owing to the changes in hydrodynamic flows are unknown. Coupled two-dimensional biogeochemical and hydrodynamic models offer the opportunity to predict potential effects of large scale TED arrays on the local and regional phytoplankton dynamics in coastal and inshore environments. Using MIKE 21 Software by DHI (https://www.dhigroup.com), coupled two-dimensional biogeochemical and hydrodynamic models were developed with simulations including no turbines or an array of 55 turbines with four solar radiation scenarios to assess the temporal and spatial changes of phytoplankton dynamics in an idealised domain. Results suggest that the effect of TEDs on phytoplankton dynamics accounted for up to 25% of the variability in phytoplankton concentrations, most likely associated with an increased residence time in an inshore basin. However, natural variation, such as the intensity of photosynthetically active radiation, had a larger effect on phytoplankton dynamics than an array of TEDs
- ItemEvaluation of growth, yield and calorific value of Miscanthus x giganteus (Poaceae) biomass established in south central of Chile(Universidad Nacional de Cuyo, 2018-07-01) Munoz, Fernando; Cancino, Jorge; Rodriquez, Roque; Olave, RodrigoExperimental crops of Miscanthus x giganteus were planted in three contrasting sites in Chile's south central to evaluate its growth and energy potential. In the second year of growth, the crop exhibited large differences amongsites regarding height (52.1 to 158.2 cm), biomass yield (1.1 to 9.0 Mg ha-1), ash content (3.8 to 9.6%) and calorific value (16.64 to 18.14 MJ kg-1). The chemical composition of the biomass indicated cellulose 36%, hemicellulose 22.3% and lignin 26.9%. Elemental analysis indicated C and H content of 41.9% and 6.6% respectively. Therefore, Miscanthus x giganteus offers suitable attributes to be used for energy generation in Chile.
- ItemEffects of the particle of ground alfalfa hay on the growth performance, methane production and archaeal populations of rabbits(Public Library of Science, 2018-09-17) Liu, Siqiang; Yuan, Mei; Jin, Dingxing; Wang, Zhisheng; Zou, Huawei; Wang, Lizhi; Xue, Bai; Wu, De; Tian, Gang; Cai, Jingyi; Yan, Tianhai; Peng, QuanhuiThe world's annual output of rabbits is over 1.2 billion, therefore this sector is also one of the sources of greenhouse gases in livestock production. One hundred-twenty New Zealand rabbits were allocated into four treatments, five replicates in each treatment and six rabbits in each replicate to examine the effect of grinding alfalfa hay to different sizes on growth performance, methane production and cecal archaeal populations. The particle sizes of the alfalfa meal in the four treatment diets were 2500, 1000, 100 and 10 μm, while the other ingredients were ground through a 2.5 mm sieve. The average daily gain (ADG) and average daily feed intake (ADFI) increased (P<0.001) as the particle size decreased, but the feed conversion ratio (FCR) was not affected (P = 0.305). The digestibility of neutral detergent fiber (NDF) (P = 0.006) and acid detergent fiber (ADF) (P<0.006) increased while the greatest digestibility of crude protein (CP) was obtained in 1000 um group (P = 0.015). The rabbits produced more methane (CH4, L/kgBM0.75/d) with decreasing alfalfa particle size (P<0.001). The molar proportion of acetic acid and propionic acid decreased (P<0.001) at the cost of butyric acid (P<0.001). The greatest villus height:crypt depth ratio were obtained in 1000 μm group, and the decrease in the alfalfa hay particle size decreased the jejunum and ilem villus height:crypt depth ratio (P<0.05). The gastric muscular and mucosal thickness decreased with decreasing alfalfa particle size (P<0.05). Archaea diversity decreased with decreasing alfalfa particle size, and the relative abundance of genus Methanobrevibacter increased (P<0.001) while the genus Methanosphaera decreased (P<0.001). It is concluded that a finer particle size favors the growth of genus Methanobrevibacter, which produces more methane but promotes the growth performance of rabbits.
- ItemBottom trawl fishing footprints on the world’s continental shelves(National Academy of Sciences, 2018-10-08) Amoroso, Ricardo O.; Pitcher, C. Roland; Rijnsdorp, Adriaan D.; McConnaughey, Robert A.; Parma, Ana M.; Suuronen, Petri; Eigaard, Ole R.; Bastardie, Francois; Hintzen, Niels T.; Althaus, Franziska; Baird, Susan Jane; Black, Jenny; Buhl-Mortensen, Lene; Campbell, Alexander B.; Catarino, Rui; Collie, Jeremy; Cowan Jr., James H.; Durholtz, Deon; Engstrom, Nadia; Fairweather, Tracey P.; Fock, Heino O.; Ford, Richard; Gálvez, Patricio A.; Gerritsen, Hans; Góngora, María Eva; González, Jessica A.; Hiddink, Jan G.; Hughes, Kathryn M.; Intelmann, Steven S.; Jenkins, Chris; Jonsson, Patrik; Kainge, Paulus; Kangas, Mervi; Kathena, Johannes N.; Kavadas, Stefanos; Leslie, Rob W.; Lewis, Steve G.; Lundy, Mathieu; Makin, David; Martin, Julie; Mazor, Tessa; Gonzalez-Mirelis, Genoveva; Newman, Stephen J.; Papadopoulou, Nadia; Posen, Paulette E.; Rochester, Wayne; Russo, Tommaso; Sala, Antonello; Semmens, Jayson M.; Silva, Cristina; Tsolos, Angelo; Vanelslander, Bart; Wakefield, Corey B.; Wood, Brent A.; Hilborn, Ray; Kaiser, Michel J.; Jennings, SimonBottom trawlers land around 19 million tons of fish and invertebrates annually, almost one-quarter of wild marine landings. The extent of bottom trawling footprint (seabed area trawled at least once in a specified region and time period) is often contested but poorly described. We quantify footprints using high-resolution satellite vessel monitoring system (VMS) and logbook data on 24 continental shelves and slopes to 1,000-m depth over at least 2 years. Trawling footprint varied markedly among regions: from <10% of seabed area in Australian and New Zealand waters, the Aleutian Islands, East Bering Sea, South Chile, and Gulf of Alaska to >50% in some European seas. Overall, 14% of the 7.8 million-km2 study area was trawled, and 86% was not trawled. Trawling activity was aggregated; the most intensively trawled areas accounting for 90% of activity comprised 77% of footprint on average. Regional swept area ratio (SAR; ratio of total swept area trawled annually to total area of region, a metric of trawling intensity) and footprint area were related, providing an approach to estimate regional trawling footprints when highresolution spatial data are unavailable. If SAR was ≤0.1, as in 8 of 24 regions, therewas >95% probability that >90%of seabed was not trawled. If SAR was 7.9, equal to the highest SAR recorded, there was >95% probability that >70% of seabed was trawled. Footprints were smaller and SAR was ≤0.25 in regions where fishing rates consistently met international sustainability benchmarks for fish stocks, implying collateral environmental benefits from sustainable fishing.
- ItemData Descriptor: A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins(Nature Research, 2018-10-23) Mantzouki, Evanthia; Campbell, James; van Loon, Emiel; Visser, Petra; Konstantinou, Iosif; Antoniou, Maria; Giuliani, Grégory; Machado-Vieira, Danielle; de Oliveira, Alinne Gurjão; Maronić, Dubravka Špoljarić; Stević, Filip; Pfeiffer, Tanja Žuna; Vucelić, Itana Bokan; Žutinić, Petar; Udovič, Marija Gligora; Plenković-Moraj, Anđelka; Tsiarta, Nikoletta; Bláha, Luděk; Geriš, Rodan; Fránková, Markéta; Christoffersen, Kirsten Seestern; Warming, Trine Perlt; Feldmann, Tõnu; Laas, Alo; Panksep, Kristel; Tuvikene, Lea; Kangro, Kersti; Häggqvist, Kerstin; Salmi, Pauliina; Arvola, Lauri; Fastner, Jutta; Straile, Dietmar; Rothhaupt, Karl-Otto; Fonvielle, Jeremy; Grossart, Hans-Peter; Avagianos, Christos; Kaloudis, Triantafyllos; Triantis, Theodoros; Zervou, Sevasti-Kiriaki; Hiskia, Anastasia; Gkelis, Spyros; Panou, Manthos; McCarthy, Valerie; Perello, Victor C.; Koreivienė, Judita; Karosienė, Jūratė; Kasperovičienė, Jūratė; Savadova, Ksenija; Vitonytė, Irma; Haande, Sigrid; Skjelbred, Birger; Grabowska, Magdalena; Mazur-Marzec, Hanna; Alcaraz-Párraga, Pablo; Wilk-Woźniak, Elżbieta; Krztoń, Wojciech; Walusiak, Edward; Gagala, Ilona; Mankiewicz-Boczek, Joana; Toporowska, Magdalena; Pawlik-Skowronska, Barbara; Niedźwiecki, Michał; Pęczuła, Wojciech; Napiórkowska-Krzebietke, Agnieszka; Dunalska, Julita; Sieńska, Justyna; Szymański, Daniel; Szeląg-Wasielewska, Elżbieta; Domek, Piotr; Jakubowska-Krepska, Natalia; Kwasizur, Kinga; Messyasz, Beata; Pełechata, Aleksandra; Pełechaty, Mariusz; Kokocinski, Mikolaj; Madrecka, Beata; Kostrzewska-Szlakowska, Iwona; Frąk, Magdalena; Bańkowska-Sobczak, Agnieszka; Wasilewicz, Michał; Ochocka, Agnieszka; Pasztaleniec, Agnieszka; Jasser, Iwona; Antão-Geraldes, Ana M.; Leira, Manel; Hernández, Armand; Vasconcelos, Vitor; Morais, João; Vale, Micaela; Raposeiro, Pedro M.; Gonçalves, Vítor; Aleksovski, Boris; Krstić, Svetislav; Nemova, Hana; Drastichova, Iveta; Chomova, Lucia; Remec-Rekar, Spela; Elersek, Tina; Delgado-Martín, Jordi; García, David; Cereijo, Jose Luís; Gomà, Joan; Trapote, Mari Carmen; Vegas-Vilarrúbia, Teresa; Obrador, Biel; García-Murcia, Ana; Real, Monserrat; Romans, Elvira; Noguero-Ribes, Jordi; Duque, David Parreño; Fernández-Morán, Elísabeth; Úbeda, Bárbara; Gálvez, José Ángel; Marcé, Rafael; Catalán, Núria; Pérez-Martínez, Carmen; Ramos-Rodríguez, Eloísa; Cillero-Castro, Carmen; Moreno-Ostos, Enrique; Blanco, José María; Rodríguez, Valeriano; Montes-Pérez, Jorge Juan; Palomino, Roberto L.; Rodríguez-Pérez, Estela; Carballeira, Rafael; Camacho, Antonio; Picazo, Antonio; Rochera, Carlos; Santamans, Anna C.; Ferriol, Carmen; Romo, Susana; Soria, Juan Miguel; Hansson, Lars-Anders; Urrutia-Cordero, Pablo; Özen, Arda; Bravo, Andrea G.; Buck, Moritz; Colom-Montero, William; Mustonen, Kristiina; Pierson, Don; Yang, Yang; Verspagen, Jolanda M. H.; de Senerpont Domis, Lisette N.; Seelen, Laura; Teurlincx, Sven; Verstijnen, Yvon; Lürling, Miquel; Maliaka, Valentini; Faassen, Elisabeth J.; Latour, Delphine; Carey, Cayelan C.; Paerl, Hans W.; Torokne, Andrea; Karan, Tünay; Demir, Nilsun; Beklioğlu, Meryem; Filiz, Nur; Levi, Eti E.; Iskin, Uğur; Bezirci, Gizem; Tavşanoğlu, Ülkü Nihan; Çelik, Kemal; Özhan, Koray; Karakaya, Nusret; Koçer, Mehmet Ali Turan; Yilmaz, Mete; Maraşlıoğlu, Faruk; Yağcı, Abdulkadir; Cesur, Mehmet; Bilgin, Fuat; Bulut, Cafer; Uysal, Rahmi; Köker, Latife; Akçaalan, Reyhan; Albay, Meriç; Alp, Mehmet Tahir; Özkan, Korhan; Sevindik, Tuğba Ongun; Tunca, Hatice; Önem, Burçin; Richardson, Jessica; Edwards, Christine; Bergkemper, Victoria; O'Leary, Sarah; Beirne, Eilish; Cromie, Hannah; Ibelings, Bastiaan W.Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The European Multi Lake Survey (EMLS) in summer 2015 was an initiative among scientists from 27 countries to collect and analyse lake physical, chemical and biological variables in a fully standardized manner. This database includes in-situ lake variables along with nutrient, pigment and cyanotoxin data of 369 lakes in Europe, which were centrally analysed in dedicated laboratories. Publishing the EMLS methods and dataset might inspire similar initiatives to study across large geographic areas that will contribute to better understanding lake responses in a changing environment.
- ItemStrong and recurring seasonality revealed within stream diatom assemblages(Springer Nature, 2019-03-01) Snell, Maria; Barker, P. A.; Surridge, B. W. J.; Benskin, C. McW. H.; Barber, N.; Reaney, S. M.; Tych, W.; Mindham, D.; Large, A. R. G.; Burke, S.; Haygarth, P. M.Improving stream water quality in agricultural landscapes is an ecological priority and a legislative duty for many governments. Ecosystem health can be effectively characterised by organisms sensitive to water quality changes such as diatoms, single-celled algae that are a ubiquitous component of stream benthos. Diatoms respond within daily timescales to variables including light, temperature, nutrient availability and flow conditions that result from weather and land use characteristics. However, little consideration has been given to the ecological dynamics of diatoms through repeated seasonal cycles when assessing trajectories of stream function, even in catchments actively managed to reduce human pressures. Here, six years of monthly diatom samples from three independent streams, each receiving differing levels of diffuse agricultural pollution, reveal robust and repeated seasonal variation. Predicted seasonal changes in climate-related variables and anticipated ecological impacts must be fully captured in future ecological and water quality assessments, if the apparent resistance of stream ecosystems to pollution mitigation measures is to be better understood.
- ItemA carrying capacity framework for soil phosphorus and hydrological sensitivity from farm to catchment scales(Elsevier, 2019-06-04) Cassidy, Rachel; Thomas, Ian A.; Higgins, Alex J.; Bailey, John S.; Jordan, PhilAgricultural fieldswith above optimumsoil phosphorus (P) are considered to pose risks to water quality and especially when those areas are coincident with hydrologically sensitive areas (HSAs) that focus surface runoff pathways. This is a challenge tomanage in areas of agricultural intensity in surfacewater dominated catchments where water quality targets have to be met. In this study, a soil P survey of 13 sub-catchments and 7693 fields was undertaken in a 220 km2 catchment. HSAs were also determined as the top 25th percentile risk froma runoff routingmodel that used a LiDAR digital elevation model and soil hydraulic conductivity properties. Distributions of these spatial data were compared with river soluble reactive phosphorus (SRP) concentration measured fortnightly over one year. The results showed that 41% of fields exceeded the agronomic optimumfor soil P across the sub-catchments.When compared with the available water quality data, the results indicated that the high soil P carrying capacity area of the sub-catchmentswas 15%. Combining high soil P and HSA, the carrying capacity area of the sub-catchmentswas 1.5%. The opportunities to redistribute these riskswere analysed on fields with below optimum soil P and where HSA risk was also minimal. These ranged from 0.4% to 13.8% of sub-catchment areas and this limited potential, unlikely to fully reduce the P pressure to over-supplied fields, would need to be considered alongside addressing this over-supply and also with targeted HSA interception measures.
- ItemEvaluation of energy balances and greenhouse gas emissions from different agricultural production systems in Minqin Oasis, China(Peer J, 2019-06-26) Yan, Zhengang; Li, Wei; Yan, Tianhai; Chang, Shenghua; Hou, FujiangAgricultural production in Minqin Oasis, China, is commonly categorized as intensive crop production (ICP), integrated crop–livestock production (ICLP), intensive livestock production (confined feeding) (IFLP), and extensive livestock production (grazing) (EGLP). The objectives of the present study were to use a life cycle assessment technique to evaluate on-farm energy balances and greenhouse gas (GHG) emissions of agricultural production, and to compare the differences among the four systems. Data used in the present study were collected from published literature and face-to face questionnaires from 529 farms in eight towns (two towns per production system) within Minqin county. The ANOVA of averaged data from 2014 to 2015 indicated that the net energy ratio (Output/Input) for the EGLP system was significantly higher than that for any other system (P < 0.01), whereas the difference among other three systems were not significant. The EGLP system generated lower CO2-eq emissions per hectare of farmland than other systems (P < 0.01). Relating carbon economic efficiency to market values (US$) of agricultural products, indicated that the carbon economic efficiency (US$/kg CO2-eq) of the IFLP system was significantly greater than that of other systems (P < 0.01). The major GHG emission sources varied across the systems, that is, soil respiration is the dominant source in EGLP, while the main sources in IFLP are enteric methane and manure management; in ICLP major sources are enteric methane, soil respiration and fertilizer; and in ICP are soil respiration and fertilizer. The structural equation modelling analysis showed that livestock category was strongly linked to net income. The direct effects and total effects of water use efficiency, via its positive influence on energy balances and GHG emissions were much stronger than those of other dependent variables. The study provides important benchmark information to help develop sustainable agricultural production systems on energy balances and GHG emissions in northwestern China.
- ItemSpotting the pests of tomorrow—Sampling designs for detection of species associations with woody plants(Wiley, 2019-08-04) Eschen, René; De Groot, Maarten; Glavendekić, Milka; Lacković, Nikola; Matosević, Dinka; Morales‐Rodriguez, Carmen; O'Hanlon, Richard; Oskay, Funda; Papazova, Irena; Prospero, Simone; Franić, IvaAim Early warning against potentially harmful organisms of woody plant species can be achieved by sampling sentinel plants in exporting countries. However, it is unclear where sentinel plants can best be located, and how many samples are required and when and how often sampling optimally should take place for the adequate assessment of the biodiversity associated with the target plant species. We aimed to review spatial and temporal factors affecting associate biodiversity of single woody plant species and to develop guidance for the design of global biodiversity sampling studies. Location Worldwide. Taxon Insects and Fungi. Methods Literature about factors affecting the diversity of insects and fungi in association with single plant species on global, regional, local and different temporal scales was reviewed. Case studies of insect and fungal diversity, primarily collected on single plant species, and the cost of collecting and analysing samples from locations around the world were analysed. Results The review of the literature illustrated various factors affecting diversity, and the case studies allowed quantification of the relative impact of some spatial, temporal and financial aspects on captured biodiversity and, thus, illustrate the need to consider all possible factors that may affect the result of the sampling when deciding on a sampling design. Main conclusions Our study illustrates the factors that should be considered when deciding on the location and timing of sampling for sentinel plants, which is important because of the trade‐off between the number of samples and sampling locations needed to detect many of the species which may be potential pests, and the cost of (repeated) sampling in many locations. Decisions about the sampling design must be based on the objective of the sampling, but our recommendations apply irrespective of the targeted plant species or country.
- ItemHow to measure, report and verify soil carbon change to realize the potential of soil carbon sequestration for atmospheric greenhouse gas removal(Wiley, 2019-08-30) Smith, Pete; Soussana, Jean‐Francois; Angers, Denis; Schipper, Louis; Chenu, Claire; Rasse, Daniel P.; Batjes, Niels H.; Egmond, Fenny van; McNeill, Stephen; Kuhnert, Matthias; Arias‐Navarro, Cristina; Olesen, Jorgen E.; Chirinda, Ngonidzashe; Fornara, Dario; Wollenberg, Eva; Álvaro‐Fuentes, Jorge; Sanz‐Cobena, Alberto; Klumpp, KatjaThere is growing international interest in better managing soils to increase soil organic carbon (SOC) content to contribute to climate change mitigation, to enhance resilience to climate change and to underpin food security, through initiatives such as international ‘4p1000’ initiative and the FAO's Global assessment of SOC sequestration potential (GSOCseq) programme. Since SOC content of soils cannot be easily measured, a key barrier to implementing programmes to increase SOC at large scale, is the need for credible and reliable measurement/monitoring, reporting and verification (MRV) platforms, both for national reporting and for emissions trading. Without such platforms, investments could be considered risky. In this paper, we review methods and challenges of measuring SOC change directly in soils, before examining some recent novel developments that show promise for quantifying SOC. We describe how repeat soil surveys are used to estimate changes in SOC over time, and how long‐term experiments and space‐for‐time substitution sites can serve as sources of knowledge and can be used to test models, and as potential benchmark sites in global frameworks to estimate SOC change. We briefly consider models that can be used to simulate and project change in SOC and examine the MRV platforms for SOC change already in use in various countries/regions. In the final section, we bring together the various components described in this review, to describe a new vision for a global framework for MRV of SOC change, to support national and international initiatives seeking to effect change in the way we manage our soils.
- ItemImproving the predictive capability of benthic species distribution models by incorporating oceanographic data – Towards holistic ecological modelling of a submarine canyon(Elsevier, 2020-04-21) Pearman, T.R.R.; Robert, K.; Callaway, Alex; Hall, R.; Lo lacono, C.; Huvenne, V.A.I.Submarine canyons are associated with increased biodiversity, including cold-water coral (CWC) colonies and reefs which are features of high conservation value that are under increasing anthropogenic pressure. Effective spatial management and conservation of these features requires accurate distribution maps and a deeper understanding of the processes that generate the observed distribution patterns. Predictive distribution modelling offers a powerful tool in the deep sea, where surveys are constrained by cost and technological capabilities. To date, predictive distribution modelling in canyons has focussed on integrating groundtruthed acoustically acquired datasets as proxies for environmental variables thought to influence faunal patterns. Physical oceanography is known to influence faunal patterns but has rarely been explicitly included in predictive distribution models of canyon fauna, thereby omitting key information required to adequately capture the species-environment relationships that form the basis of predictive distribution modelling. In this study, acoustic, oceanographic and biological datasets were integrated to undertake high-resolution predictions of benthic megafaunal diversity and CWC distribution within Whittard Canyon, North-East Atlantic. The main aim was to investigate which environmental variables best predict faunal patterns in canyons and to assess whether including oceanographic data improves predictive modelling. General additive models, random forests and boosted regression trees were used to build predictive maps for CWC occurrence, megafaunal abundance, species richness and biodiversity. To provide more robust predictions, ensemble techniques that summarise the variation in predictions and uncertainties between modelling approaches were applied to build final maps. Model performance improved with the inclusion of oceanographic data. Ensemble maps identified areas of elevated current speed that coincided with steep ridges and escarpment walls as the areas most likely to harbour CWCs and increased biodiversity, probably linked to local hydrodynamics interacting with topography to concentrate food resources. This study shows how incorporating oceanographic data into canyon models can broaden our understanding of processes generating faunal patterns and improve the mapping of features of conservation, supporting effective procedures for spatial ecosystem management.
- ItemNitrogen surplus – a unified indicator for water pollution in for Europe?(MDPI, 2020-04-22) Klages, Susanne; Heidecke, Claudia; Osterburg, Bernhard; Bailey, John S.; Calciu, Irina; Casey, Clare; Dalgaard, Tommy; Frick, Hanna; Glavan, Matjaz; D'Haene, Karoline; Hofman, Georges; Leitao, Ines Amorim; Surdyk, Nicolas; Verloop, Koos; Velthof, GerardPollution of ground-and surface waters with nitrates from agricultural sources poses a risk to drinking water quality and has negative impacts on the environment. At the national scale, the gross nitrogen budget (GNB) is accepted as an indicator of pollution caused by nitrates. There is, however, little common EU-wide knowledge on the budget application and its comparability at the farm level for the detection of ground-and surface water pollution caused by nitrates and the monitoring of mitigation measures. Therefore, a survey was carried out among experts of various European countries in order to assess the practice and application of fertilization planning and nitrogen budgeting at the farm level and the differences between countries within Europe. While fertilization planning is practiced in all of the fourteen countries analyzed in this paper, according to current legislation, nitrogen budgets have to be calculated only in Switzerland, Germany and Romania. The survey revealed that methods of fertilization planning and nitrogen budgeting at the farm level are not unified throughout Europe. In most of the cases where budgets are used regularly (Germany, Romania, Switzerland), standard values for the chemical composition of feed, organic fertilizers, animal and plant products are used. The example of the Dutch Annual Nutrient Cycling Assessment (ANCA) tool (and partly of the Suisse Balance) shows that it is only by using farm-specific “real” data that budgeting can be successfully applied to optimize nutrient flows and increase N efficiencies at the farm level. However, this approach is more elaborate and requires centralized data processing under consideration of data protection concerns. This paper concludes that there is no unified indicator for nutrient management and water quality at the farm level. A comparison of regionally calculated nitrogen budgets across European countries needs to be interpreted carefully, as methods as well as data and emission factors vary across countries. For the implementation of EU nitrogen-related policies—notably, the Nitrates Directive—nutrient budgeting is currently ruled out as an entry point for legal requirements. In contrast, nutrient budgets are highlighted as an environment indicator by the OECD and EU institutions.
- ItemAtlantic salmon smolts in the Irish Sea: First evidence of a northerly migration trajectory(Wiley, 2020-06-09) Barry, James; Kennedy, Richard; Rosell, Robert S.; Roche, William K.Results from an acoustic telemetry study revealed for the first time a northerly migration route for Atlantic salmon (Salmo salar L.) smolts leaving the east coast of Ireland. Atlantic salmon smolts were tagged in spring 2019 in the Castletown and Boyne rivers. Three tagged smolts registered on disparate deep‐water offshore marine receivers as they travelled northwards out of the Irish Sea through the North Channel. One fish had migrated an estimated 250 km in a period of 32 days. The remaining two individuals were detected on receivers located off the Northern Ireland coast, further corroborating the northward migration of salmon smolts through the Irish Sea.
- ItemMethods and approaches to advance soil macroecology(Wiley, 2020-08-02) White, Hannah J.; León-Sánchez, Lupe; Burton, Victoria J.; Cameron, Erin K.; Caruso, Tancredi; Cunha, Luís; Dirilgen, Tara; Jurburg, Stephanie D.; Kelly, Ruth; Kumaresan, Deepak; Ochoa-Hueso, Raúl; Ordonez, Alejandro; Phillips, Helen R.P.; Prieto, Iván; Schmidt, Olaf; Caplat, PaulMotivation and aim Soil biodiversity is central to ecosystem function and services. It represents most of terrestrial biodiversity and at least a quarter of all biodiversity on Earth. Yet, research into broad, generalizable spatial and temporal patterns of soil biota has been limited compared to aboveground systems due to complexities of the soil system. We review the literature and identify key considerations necessary to expand soil macroecology beyond the recent surge of global maps of soil taxa, so that we can gain greater insight into the mechanisms and processes shaping soil biodiversity. We focus primarily on three groups of soil taxa (earthworms, mycorrhizal fungi and soil bacteria) that represent a range of body sizes and ecologies, and, therefore, interact with their environment at different spatial scales. Results The complexities of soil, including fine‐scale heterogeneity, 3‐D habitat structure, difficulties with taxonomic delimitation, and the wide‐ranging ecologies of its inhabitants, require the classical macroecological toolbox to be expanded to consider novel sampling, molecular identification, functional approaches, environmental variables, and modelling techniques. Main conclusions Soil provides a complex system within which to apply macroecological research, yet, it is this property that itself makes soil macroecology a field ripe for innovative methodologies and approaches. To achieve this, soil‐specific data, spatio‐temporal, biotic, and abiotic considerations are necessary at all stages of research, from sampling design to statistical analyses. Insights into whole ecosystems and new approaches to link genes, functions and diversity across spatial and temporal scales, alongside methodologies already applied in aboveground macroecology, invasion ecology and aquatic ecology, will facilitate the investigation of macroecological processes in soil biota, which is key to understanding the link between biodiversity and ecosystem functioning in terrestrial ecosystems.
- ItemPreventing and mitigating farmed bivalve disease: a Northern Ireland case study(Springer, 2020-08-26) Fox, M.; Christley, R.; Lupo, C.; Moore, H.; Service, Matthew; Campbell, K.Shellfish production forms a large proportion of marine aquaculture production in Northern Ireland (NI). Diseases represent a serious threat to the maintenance and growth of shellfish cultivation with severe consequences to production output and profitability. In Northern Ireland, production generally benefits from a good health status with the absence of notifiable diseases, except for localised cases of Bonamia ostreae, Marteilia refringens and ostreid herpes virus. In this paper, we qualitatively explore that the prevalence, risk, impact, mitigation and experience shellfish farmers in this region have in relation to disease. Sixteen semistructured interviews were conducted with stakeholders within the sector. The interviews were transcribed verbatim, and Nvivo 12 was used to facilitate an inductive thematic analysis. Our results highlighted that the industry has varying attitudes and experiences with disease. At present-day temperatures, disease is not an issue and this provides vast market opportunities for the region. However, disease outbreaks have led to detrimental consequences to financial income, production output and reputation in the past, whilst control and mitigation remain reactive. It is imperative proactive disease prevention and control that are employed and enforced to sustain NI’s reputation as a healthy shellfish region, particularly under increasing global temperatures and intensified production systems. A cultural shift to disease appreciation, risk analysis and surveillance through research, education, training and collaboration is essential. This study highlights the importance of providing a bottom-up communication platform with the stakeholders directly involved in shellfish culture and management, the value of cross sector engagement and the need to improve knowledge transfer between science the sector.
- ItemApproaches to herbicide (MCPA) pollution mitigation in drinking water source catchments using enhanced space and time monitoring(Elsevier, 2020-10-08) Morton, Phoebe; Cassidy, Rachel; Floyd, Stewart D.; Doody, Donnacha; McRoberts, W. Colin; Jordan, PhilipFreshwater occurrences of the selective acid herbicide 2-methyl-4-chloro-phenoxyacetic acid (MCPA) are an ongoing regulatory and financial issue for water utility industries as the number and magnitude of detections increase, particularly in surface water catchments. Assessments for mitigating pesticide pollution in catchments used as drinking water sources require a combination of catchment-based and water treatment solutions, but approaches are limited by a lack of empirical data. In this study, an enhanced spatial (11 locations) and temporal (7-hourly to daily sampling) monitoring approach was employed to address these issues in an exemplar surface water source catchment (384 km2). The spatial sampling revealed that MCPA was widespread, with occurrences above the 0.1 μg L−1 threshold for a single pesticide being highly positively correlated to sub-catchments with higher proportions of ‘Improved Grassland’ land use (r = 0.84). These data provide a strong foundation for targeting catchment-based mitigation solutions and also add to the debate on the ecosystems services provided by such catchments. Additionally, of the 999 temporal samples taken over 12 months from the catchment outlet, 25% were above the drinking water threshold of 0.1 μg L−1. This prevalence of high concentrations presents costly problems for source water treatment. Using these data, abstraction shutdowns were simulated for five scenarios using hydrometeorological data to explore the potential to avoid intake of high MCPA concentrations. The scenarios stopped abstraction for 4.2–9.3% of the April–October period and reduced intake of water containing over 0.1 μg L−1 of MCPA by 16–31%. This represents an important development for real-time proxy assessments for water abstraction in the absence of more direct pesticide monitoring data.