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Towards better survival: modeling drivers for daily mortality in Norwegian Atlantic salmon farming

PREVENTIVE VETERINARY MEDICINE 2023年 210卷 105798页

作者： Tvete, Ingunn Fride Aldrin, Magne Jensen, Britt Bang Norwegian Comp Ctr Mailbox 114 Blindern N-0314 Oslo Norway Norwegian Vet Inst Mailbox 64 N-1431 As Norway

Mortality in the production of farmed salmonids is a major constraint to the sustainability of this form of animal husbandry. We have developed a model for the daily mortality in salmon farming over a full production cycle from stocking to harvest, considering different environmental and production factors. These factors included sea temperature, salinity, day within year, fish weight at stocking, stocking day, four types of lice treatments and the possible occurrence of pancreas disease (PD). We considered a generalized additive model following full pro-duction cycles, allowing for non-linear descriptions of how relevant factors relate to the daily mortality. We saw a high overall mortality rate immediately after stocking, which decreased the first three months in the cycle and thereafter increased. We found that the total mortality could be reduced by 21% if avoiding all lice treatments, and similarly reduced by 20% if no PD infections occurred. If avoiding jointly PD and all lice treatments, the accumulated mortality could be reduced by 34%. A single thermal or hydrogen peroxide treatment was asso-ciated with a mortality of around 1.6% and 1.3%, respectively. This modeling approach gave a unique oppor-tunity to model how different factors interact on the overall global mortality and can easily be extended by other factors, such as additional fish diseases.

关键词： Full production cycles generalized additive model Lice treatments Mortality Pancreas disease

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Evolving Drivers of Brazilian SARS-CoV-2 Transmission: A Spatiotemporally Disaggregated Time Series Analysis of Meteorology, Policy, and Human Mobility

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GEOHEALTH 2023年第3期7卷 e2022GH000727页

作者： Kerr, Gaige Hunter Badr, Hamada S. Barbieri, Alisson F. Colston, Josh M. Gardner, Lauren M. Kosek, Margaret N. Zaitchik, Benjamin F. George Washington Univ Dept Environm & Occupat Hlth Washington DC 20052 USA Johns Hopkins Univ Dept Civil & Syst Engn Baltimore MD USA Amazon Web Serv Now Sales Market & Global Serv Seattle WA USA Univ Fed Minas Gerais Demog Dept Belo Horizonte Brazil Univ Virginia Div Infect Dis & Int Hlth Sch Med Charlottesville VA USA Johns Hopkins Univ Dept Earth & Planetary Sci Baltimore MD USA

Brazil has been severely affected by the COVID-19 pandemic. Temperature and humidity have been purported as drivers of SARS-CoV-2 transmission, but no consensus has been reached in the literature regarding the relative roles of meteorology, governmental policy, and mobility on transmission in Brazil. We compiled data on meteorology, governmental policy, and mobility in Brazil's 26 states and one federal district from June 2020 to August 2021. Associations between these variables and the time-varying reproductive number (R-t) of SARS-CoV-2 were examined using generalized additive models fit to data from the entire 15-month period and several shorter, 3-month periods. Accumulated local effects and variable importance metrics were calculated to analyze the relationship between input variables and R-t. We found that transmission is strongly influenced by unmeasured sources of between-state heterogeneity and the near-recent trajectory of the pandemic. Increased temperature generally was associated with decreased transmission and increased specific humidity with increased transmission. However, the impacts of meteorology, policy, and mobility on R-t varied in direction, magnitude, and significance across our study period. This time variance could explain inconsistencies in the published literature to date. While meteorology weakly modulates SARS-CoV-2 transmission, daily or seasonal weather variations alone will not stave off future surges in COVID-19 cases in Brazil. Investigating how the roles of environmental factors and disease control interventions may vary with time should be a deliberate consideration of future research on the drivers of SARS-CoV-2 transmission.

关键词： COVID-19 Brazil meteorology non-pharmacological interventions generalized additive model pandemic

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Effects of change in streamflow patterns on water quality

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JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022年第PartA期302卷 113991-113991页

作者： Patil, Rupesh Wei, Yongping Pullar, David Shulmeister, James Univ Queensland Sch Earth & Environm Sci St Lucia Qld 4072 Australia Univ Canterbury Sch Earth & Environm Christchurch 8140 New Zealand

Streamflow patterns are closely linked with the quality of stream water, but they are often dealt separately. Due to this, the effects of change in streamflow patterns resulting from river regulation and flow diversion on stream water quality remain under-investigated. This study models change in water quality indicators including pollutants (total suspended solids and turbidity), nutrients (total nitrogen and phosphorus), dissolved oxygen, nitrogen (kjeldahl), pH, and salinity caused by the change in streamflow patterns under different scenarios of river regulation, flow diversion, and rainfall. The generalized additive model was used and the Goulburn-Broken catchment, Australia was chosen as the case study. It was found that concentrations of pollutants and nutrients increased by 38% while dissolved oxygen and nitrogen (kjeldahl) decreased by 35% during the period 1990-2018. These changes were associated with an average increase of 20% in low and medium flows, an average decline of 22% in high and overbank flows and a 15% decline in rainfall. Under the scenario of climate change, river regulation and flow diversion, the overbank flow patterns would mimic the effects of low and medium flows on the water quality indicators that would raise the concentration of pollutants, nutrients, and salinity by 19%. Restoration of high flows would decrease these concentrations by 28% relative to current concentrations, however, it would also reduce dissolved oxygen, nitrogen (kjeldahl), and pH. Effects of streamflow patterns on water quality have implications for environmental flow management, thus, this study recommends critical adjustments in low, medium, and high flows for improving water quality.

关键词： Stream water quality Streamflow patterns Regulation rules generalized additive model Environmental flows Strategy reforms

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Low emission zones reduced PM10 but not NO2 concentrations in Berlin and Munich, Germany

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JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022年第PartA期302卷 114048-114048页

作者： Gu, Jianwei Deffner, Veronika Kuechenhoff, Helmut Pickford, Regina Breitner, Susanne Schneider, Alexandra Kowalski, Michal Peters, Annette Lutz, Martin Kerschbaumer, Andreas Slama, Remy Morelli, Xavier Wichmann, Heinz-Erich Cyrys, Josef Guangdong Univ Technol Sch Environm Sci & Engn Inst Environm Hlth & Pollut Control Guangzhou 510006 Peoples R China Helmholtz Zentrum Munchen Inst Epidemiol Ingolstadter Landstr 1 D-85764 Neuherberg Germany Univ Augsburg Environm Sci Ctr Univ Sstr 1a D-86159 Augsburg Germany Ludwig Maximilians Univ Munchen Dept Stat Stat Consulting Unit StaBLab Akad Str 1 D-80799 Munich Germany Referat Immissionsschutz Senate Dept Environm Transport & Climate Protect Bruckenstr 6 D-10179 Berlin Germany Univ Grenoble Alpes Inst Adv Biosci IAB Joint Res Ctr Team Environm Epidemiol CNRSInserm Grenoble France

Low emission zones (LEZs) aiming at improving the air quality in urban areas have been implemented in many European cities. However, studies are limited in evaluating the effects of LEZ, and most of which used simple methods. In this study, a general additive mixed model was utilized to account for confounders in the atmosphere and validate the effects of LEZ on PM10 and NO2 concentrations in two German cities. In addition, the effects of LEZ on elemental carbon (EC) and total carbon (TC) in Berlin were also evaluated. The LEZ effects were estimated after taking into account air pollutant concentrations at a reference site located in the regional background, and adjusting for hour of the week, public holidays, season, and wind direction. The LEZ in Berlin, and the LEZ in combination with the heavy-duty vehicle (HDV) transit ban in Munich significantly reduced the PM10 concentrations, at both traffic sites (TS) and urban background sites (UB). The effects were greater in LEZ stage 3 than in LEZ stages 2 and 1. Moreover, compared with PM10, LEZ was more efficient in reducing EC, a component that is considered more toxic than PM10 mass. In contrast, the LEZ had no consistent effect on NO2 levels: no effects were observed in Berlin;in Munich, the combination of the LEZ and the HDV transit ban reduced NO2 at UB site in LEZ stage 1, but without further reductions in subsequent stages of the LEZ. Overall, our study indicated that LEZs, which target the major primary air pollution source in the highly populated city center could be an effective way to improve urban air quality such as PM mass concentration and EC level.

关键词： Low emission zone Air quality PM10 NO2 Vehicular emission generalized additive model

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Network analysis of water-related ecosystem services in search of solutions for sustainable catchment management: A case study in Sutlej-Beas River systems, India

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ECOSYSTEM SERVICES 2023年 63卷

作者： Yu, Shuying Peng, Jian Xia, Pei Wang, Qi Grabowski, Robert C. Azhoni, Adani Bala, Brij Shankar, Vijay Meersmans, Jeroen Peking Univ Coll Urban & Environm Sci Lab Earth Surface Proc Minist Educ Beijing 100871 Peoples R China Peking Univ Sch Urban Planning & Design Shenzhen Grad Sch Key Lab Environm & Urban Sci Shenzhen 518055 Peoples R China Cranfield Univ Ctr Water Environm & Dev Sch Water Energy & Environm Cranfield MK43 0AL England Natl Inst Technol Karnataka Dept Civil Engn Surathkal India CSKHPKV COA Dept Agr Econ Palampur Himachal Prades India Natl Inst Technol Hamirpur Civil Engn Dept Hamirpur Himachal Prades India Univ Liege TERRA Teaching & Res Ctr Gembloux Agrobio Tech B-5030 Gembloux Belgium

Hydrological processes and ecosystem interactions are instrumental in sustaining local populations by providing various water-related ecosystem services (ES). Numerous studies gave priority to the theories and methods of building networks that emphasized different stakeholders. However, little study has examined the complex relationships among water-related ES themselves and how relevant human activities affect ES networks. To narrow this gap, in this study we quantified four critical water-related ES (flood mitigation, hydropower production, soil retention, and water conservation), set up six ES network types based on the synergy relationship, and further explored the effect of human activities on these networks. The results showed that among six ES network categories, networks with four fully linked ES occupied a large percentage of 23.20% while the network with one central ES linking two others accounted for the lowest percentage (9.28%). Compared with other ES, soil retention tended to be less centralized within the networks. In addition, land use intensity was found to greatly influence the ES networks compared with other indicators, especially for less complex networks. Our results highlighted the importance of network analysis in searching solutions for sustainable catchment management.

关键词： Ecosystem services network Water-related ecosystem services Ecosystem synergy generalized additive model

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Association between nitrogen dioxide concentration and hypertension hospitalization: A multicenter time-series analysis in Xinxiang, China

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ATMOSPHERIC POLLUTION RESEARCH 2023年第6期14卷

作者： Ge, Shi-qi Wang, Yong-bin Lin, Fei Miao, Run-ran Zhang, Kai Li, Li Guo, Hui-ge Wang, Qian Zhang, Li Chen, Zhi-gang Zhao, Guo-an Xinxiang Med Univ Affiliated Hosp 1 Xinxiang Henan Peoples R China Xinxiang Med Univ Sch Publ Hlth Xinxiang Henan Peoples R China

Hypertension is a common chronic disease, and air pollution is strongly associated with hypertension hospi-talization. However, the association between nitrogen dioxide (NO2)1 concentration and hypertension hospi-talization has rarely been studied. We collected daily data on hypertension hospitalizations, air pollutants, and meteorology from January 1, 2016 to October 31, 2021. After controlling for the effects of seasonal and long-term trends, weather conditions, weekdays, holidays, and during the novel coronavirus crown epidemic, a generalized additive model with over discrete Poisson regression was used to simulate the association between NO2 concentration and hypertension hospitalizations while quantifying hypertension hospitalizations, hospital stays, and hospital costs attributable to NO2. The results showed that each 10 mu g/m3 increase in NO2 concen-tration was significantly associated with the relative risk (RR) of hypertension admission in Xinxiang, with the greatest effect at lag04 (RR = 1.107;95% confidence interval, 1.046-1.172). Hypertension hospitalizations attributed to NO2 during the study period accounted for 9.70% (484) of the total hypertension hospitalizations, equivalent to 4202 hospital days and 338.55 thousand United States dollars (USD). Increased NO2 concentration increases the risk of hypertension hospitalization in Xinxiang, which poses a significant health and economic burden to society and patients. The findings of this study provide a basis for developing stricter environmental pollutant standards.

关键词： Nitrogen dioxide Hypertension Time-series analysis generalized additive model Hospitalization

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Balancing the Effects of Forest Conservation and Restoration on South China Karst Greening

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EARTHS FUTURE 2023年第6期11卷

作者： Peng, Jian Hu, Tao Qiu, Sijing Hu, Yi'na Dong, Jianquan Lin, Yifan Peking Univ Coll Urban & Environm Sci Lab Earth Surface Proc Minist Educ Beijing Peoples R China Renmin Univ China High Sch Beijing Peoples R China Shanghai Normal Univ Sch Environm & Geog Sci Shanghai Peoples R China

Forest conservation and restoration are key components of ecological engineering. Previous studies often focused on the forest restoration impact on vegetation greening, ignoring the importance of forest conservation, and the link between forest conservation and restoration remains unclear. Based on land use data, forest cover loss data, and Moderate Resolution Imaging Spectroradiometer Leaf Area Index, in this study, we explored the spatial pattern of forest conservation and restoration from 2000 to 2020, and quantitatively calculated the contribution of forest conservation and restoration to vegetation greening. The results showed that the forest conservation area was 821,888 km(2), and the forest restoration area was 100,266 km(2) in South China karst. The forest conservation and restoration area with vegetation greenness increasing were 358,236 and 54,397 km(2), respectively, which contributed 39.85% and 6.05% to vegetation greening. Moreover, there was a nonlinear relationship between forest conservation and restoration, and the results showed an inverted U-shape in most provinces. This study evaluated ecological engineering from the perspective of forest conservation and restoration, which could provide the scientific basis for differentiated ecological engineering planning.

关键词： forest conservation forest restoration karst vegetation greening generalized additive model

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Dynamic copula-based expectile portfolios

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JOURNAL OF ASSET MANAGEMENT 2021年第3期22卷 209-223页

作者： Sahamkhadam, Maziar Linnaeus Univ Sch Business & Econ Dept Accounting & Logist PG Vejdes Vag S-35195 Vaxjo Sweden

This study investigates expectile Value-at-Risk (EVaR) as a risk measure in dynamic copula-based portfolio optimization, compared with the common variance and CVaR. To estimate the dependence structure between asset returns, the canonical vine copula augmented with the generalized additive models (GAMC-vine) is used. Applying multivariate conditional distributions from the GAMC-vine model, step-ahead asset return forecasts are obtained and used to construct dynamic copula-based EVaR portfolios. Using ten S&P 500 industry sectors, EVaR leads to a min-risk dynamic GAMC-vine portfolio that achieves higher out-of-sample average return and risk-adjusted ratios. Furthermore, EVaR shows a better portfolio ranking than CVaR. Moreover, the copula-based variance and EVaR portfolios show higher-order stochastic dominance compared to CVaR strategies. Finally, a subsample stochastic dominance analysis reveals that, in overall, the risk minimization does not benefit from the choice of risk modeling. However, the dynamic copula model leads to optimal portfolios that dominate the equally weighted benchmark more often compared to those from historical approach.

关键词： Expectile value-at-risk Dynamic vine copula generalized additive model Stochastic dominance

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Impact of climate change on hiking: quantitative evidence through big data mining

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CURRENT ISSUES IN TOURISM 2021年第21期24卷 3040-3056页

作者： Liu, Jun Yang, Luyu Zhou, Haiyue Wang, Shenghong Sichuan Univ Tourism Sch Chengdu Peoples R China

This study measures quantitatively the impact of climate change on hiking across 100 cities in China by analyzing tourist-generated big data with a hybrid method involving the generalized additive model and segmented regression model. The results indicate that temperature, relative humidity, and sunshine duration influence hiking participation nonlinearly, with threshold effects. Results from a simulation study show that hiking in over 90% of the cities studied will be affected negatively by climate change in the future. The hiking duration will drop by 7.17% to 7.39% in 2050 and 7.16% to 7.57% in 2080 under RCP 4.5. The situation is even worse under RCP 8.5. We encourage the use of this approach among nations or regions with such available data for further research.

关键词： tourism climate change hiking big data generalized additive model

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modelling driving factors of PM2.5 concentrations in port cities of the Yangtze River Delta

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MARINE POLLUTION BULLETIN 2022年 184卷 114131页

作者： Zhang, Yang Zhou, Rui Hu, Daoxian Chen, Jihong Xu, Lang Shanghai Maritime Univ Coll Transport & Commun Shanghai 201306 Peoples R China Shenzhen Int Maritime Inst Shenzhen 518081 Peoples R China Hyde Guangzhou Int Logist Grp Co LTD Guangzhou 510665 Peoples R China Shenzhen Univ Coll Management Shenzhen 518073 Peoples R China Xian Int Univ Commercial Coll Xian 710077 Peoples R China

PM2.5 is one of the major air pollutants in port cities of the Yangtze River Delta (YRD) of China. Understanding the driving factors of PM2.5 is essential to guide air pollution prevention and control. We selected 17 major port cities in YRD to study the driving factors of PM2.5 in 2019 and 2020. generalized additive models were built to model the non-linear effects of single, multiple and interactions of driving factors on the variations of PM2.5. NO2, SO2 and the day of year are most strongly associated with the variation of PM2.5 concentration when used alone. Anthropogenic emissions play complicated roles in regulating PM2.5 concentration. Although the effect of cargo throughput (CT) on PM2.5 concentration is non-monotonic, higher PM2.5 levels are found to be associated with higher levels of SO2 and CT. This work can potentially provide a scientific basis for formulating PM2.5 prevention and control policies in the region.

关键词： PM2.5 Port cities Meteorological factors Anthropogenic emissions Cargo throughput generalized additive model

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