Drought is mainly triggered by the lack of precipitation, which can lead to insufficient water supply for crops thus affecting their growth and development. Reliable drought monitoring is crucial to understanding drought risk and avoiding drought-induced crop yield losses. Based on the Stacking regression method and multiple remotely-sensed drought factors from 2001 to 2017, this study developed an ensemble learning framework for monitoring agricultural drought in major winter wheat-producing areas in China. Stacking used five machine learning algorithms, namely, extreme gradient boosting, support vector regression, extra trees, and multi-layer perceptron, as the base learners to model the relationship between remote sensing drought factors and 1-, 3-, and 6-month standardized precipitation evapotranspiration index (SPEI). In this study, county-level winter wheat yield records and drought maps provided by the Global SPEI database (SPEIbase) were adopted to assess the suitability of Stacking-predicted SPEI drought maps in agricultural drought monitoring. The results show that Stacking outperformed other machine learning algorithms in terms of estimation accuracy, with the highest R2 value of 0.77 and the lowest root mean square error (RMSE) of 0.47. The longer the time scale of model-predicted SPEI, the higher its correlation with detrended winter wheat yields. The comparison with the drought maps of SPEIbase shows that the Stacking-predicted drought maps successfully captured the spatial pattern and intensity change of drought events. The approach presented in the study has good applicability for agricultural drought monitoring and could be extended to the rest of the areas.
{"title":"Ensemble learning based on remote sensing data for monitoring agricultural drought in major winter wheat-producing areas of China","authors":"Lunche Wang, Yuefan Zhang, Xinxin Chen, Yuting Liu, Shaoqiang Wang, Lizhe Wang","doi":"10.1177/03091333231188814","DOIUrl":"https://doi.org/10.1177/03091333231188814","url":null,"abstract":"Drought is mainly triggered by the lack of precipitation, which can lead to insufficient water supply for crops thus affecting their growth and development. Reliable drought monitoring is crucial to understanding drought risk and avoiding drought-induced crop yield losses. Based on the Stacking regression method and multiple remotely-sensed drought factors from 2001 to 2017, this study developed an ensemble learning framework for monitoring agricultural drought in major winter wheat-producing areas in China. Stacking used five machine learning algorithms, namely, extreme gradient boosting, support vector regression, extra trees, and multi-layer perceptron, as the base learners to model the relationship between remote sensing drought factors and 1-, 3-, and 6-month standardized precipitation evapotranspiration index (SPEI). In this study, county-level winter wheat yield records and drought maps provided by the Global SPEI database (SPEIbase) were adopted to assess the suitability of Stacking-predicted SPEI drought maps in agricultural drought monitoring. The results show that Stacking outperformed other machine learning algorithms in terms of estimation accuracy, with the highest R2 value of 0.77 and the lowest root mean square error (RMSE) of 0.47. The longer the time scale of model-predicted SPEI, the higher its correlation with detrended winter wheat yields. The comparison with the drought maps of SPEIbase shows that the Stacking-predicted drought maps successfully captured the spatial pattern and intensity change of drought events. The approach presented in the study has good applicability for agricultural drought monitoring and could be extended to the rest of the areas.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"1 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76176156","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-11DOI: 10.1177/03091333231189045
J. Wan, Chunjing Wang, P. Marquet
To improve the effectiveness of biodiversity conservation and risk assessments under global changes, it is necessary to understand the drivers of terrestrial biodiversity on a global scale. Environmental heterogeneity is an important umbrella term for different environmental factors that contribute to species diversity. Previous studies have shown that there are significant relationships between geodiversity and biodiversity on a global scale, and that heterogeneity in geodiversity features and environmental variables, that is indicators of environmental heterogeneity (EH), drive biodiversity at local and regional scales. However, we do not yet know how terrestrial biodiversity is maintained, how well represented are the different taxa, and where would they be more at risks considering their abundances and diversities. In this study, we quantified EH of climate, topography, and land cover. We used four theoretical indexes (i.e., Fisher’s alpha, Shannon’s H, Hurlbert’s PIE, and Good’s u) to quantify terrestrial biodiversity based on abundance and diversity. We used regression models to explore the relationships between environmental heterogeneity and terrestrial biodiversity across different organismic groups (ants, bats, birds, butterflies, frogs, ground beetles, mosquitoes, odonates, orthopterans, rodents, scarab beetles, and trees) globally. We found significant relationships between environmental heterogeneity and terrestrial biodiversity, particularly for trees across the three EH components (climate, topography, and land cover), however, the effects of environmental heterogeneity on terrestrial biodiversity may vary among different groups of organisms. Land cover EH could affect the terrestrial biodiversity for ants, bats, birds, butterflies, frogs, mosquitoes, odonates, orthopterans, rodents, and scarab beetles. Furthermore, there were significant relationships between topographic EH and the terrestrial biodiversity for bats, butterflies, ground beetles, odonates, and trees. Climatic EH had significant effects on the terrestrial biodiversity for all organism groups. Our study provides new insights into biodiversity conservation by considering the terrestrial biodiversity based on EH, an indicator of geodiversity.
为了提高全球变化下陆地生物多样性保护和风险评估的有效性，有必要在全球尺度上了解陆地生物多样性的驱动因素。环境异质性是影响物种多样性的环境因素的重要总称。以往的研究表明，在全球尺度上，地质多样性与生物多样性之间存在着显著的关系，地质多样性特征的异质性和环境变量的异质性(即环境异质性指标)在局部和区域尺度上驱动着生物多样性。然而，我们还不知道陆地生物多样性是如何维持的，不同分类群的代表性如何，以及考虑到它们的丰富度和多样性，它们在哪里面临的风险更大。在这项研究中，我们量化了气候、地形和土地覆盖的EH。采用Fisher’s alpha、Shannon’s H、Hurlbert’s PIE和Good’s u 4个理论指标对陆地生物多样性丰度和多样性进行量化。我们利用回归模型探讨了全球不同生物类群(蚂蚁、蝙蝠、鸟类、蝴蝶、青蛙、地甲虫、蚊子、齿形动物、直齿动物、啮齿动物、圣甲虫和树木)的环境异质性与陆地生物多样性之间的关系。我们发现环境异质性与陆地生物多样性之间存在显著的关系，特别是对于三个EH组成部分(气候、地形和土地覆盖)的树木，然而，环境异质性对陆地生物多样性的影响可能在不同的生物群体中有所不同。土地覆盖EH会影响蚂蚁、蝙蝠、鸟类、蝴蝶、青蛙、蚊子、齿形动物、矫形动物、啮齿动物和圣甲虫的陆地生物多样性。此外，地形EH与蝙蝠、蝴蝶、地甲虫、齿形动物和树木的陆地生物多样性之间存在显著的关系。气候EH对陆地生物多样性有显著影响。基于地质多样性指标EH的陆地生物多样性研究为生物多样性保护提供了新的思路。
{"title":"Environmental heterogeneity as a driver of terrestrial biodiversity on a global scale","authors":"J. Wan, Chunjing Wang, P. Marquet","doi":"10.1177/03091333231189045","DOIUrl":"https://doi.org/10.1177/03091333231189045","url":null,"abstract":"To improve the effectiveness of biodiversity conservation and risk assessments under global changes, it is necessary to understand the drivers of terrestrial biodiversity on a global scale. Environmental heterogeneity is an important umbrella term for different environmental factors that contribute to species diversity. Previous studies have shown that there are significant relationships between geodiversity and biodiversity on a global scale, and that heterogeneity in geodiversity features and environmental variables, that is indicators of environmental heterogeneity (EH), drive biodiversity at local and regional scales. However, we do not yet know how terrestrial biodiversity is maintained, how well represented are the different taxa, and where would they be more at risks considering their abundances and diversities. In this study, we quantified EH of climate, topography, and land cover. We used four theoretical indexes (i.e., Fisher’s alpha, Shannon’s H, Hurlbert’s PIE, and Good’s u) to quantify terrestrial biodiversity based on abundance and diversity. We used regression models to explore the relationships between environmental heterogeneity and terrestrial biodiversity across different organismic groups (ants, bats, birds, butterflies, frogs, ground beetles, mosquitoes, odonates, orthopterans, rodents, scarab beetles, and trees) globally. We found significant relationships between environmental heterogeneity and terrestrial biodiversity, particularly for trees across the three EH components (climate, topography, and land cover), however, the effects of environmental heterogeneity on terrestrial biodiversity may vary among different groups of organisms. Land cover EH could affect the terrestrial biodiversity for ants, bats, birds, butterflies, frogs, mosquitoes, odonates, orthopterans, rodents, and scarab beetles. Furthermore, there were significant relationships between topographic EH and the terrestrial biodiversity for bats, butterflies, ground beetles, odonates, and trees. Climatic EH had significant effects on the terrestrial biodiversity for all organism groups. Our study provides new insights into biodiversity conservation by considering the terrestrial biodiversity based on EH, an indicator of geodiversity.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"56 4 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76093627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-08DOI: 10.1177/03091333231193844
J. Eichel, M. Stoffel, S. Wipf
High mountains are climate change hotspots. Quickly rising temperatures trigger vegetation shifts such as upslope migration, possibly threatening mountain biodiversity. At the same time, mountain slopes are becoming increasingly unstable due to degrading permafrost and changing rain and snowfall regimes, which favour slope movements such as rockfall and debris flows. Slope movements can limit plant colonization, while, at the same time, plant colonization can stabilize moving slopes. Thus, we here propose that response of high mountain environments to climate change depends on a ‘biogeomorphic balance’ between slope movement intensity and the trait-dependent ability of mountain plants to survive and stabilize slopes. We envision three possible scenarios of biogeomorphic balance: (1) Intensifying slope movements limit vegetation shifts and thus amplify instability. (2) Shifting ecosystem engineer species reduce slope movement and facilitate shifts for less movement-adapted species. (3) Trees and tall shrubs shifting on stable slopes limit slope instability but decrease biodiversity. Previous geomorphic, ecological and palaeoecological studies support all three scenarios. Given differences in ecologic and geomorphic response rates to climate change, as well as high environmental heterogeneity and elevational gradients in mountain environments, we posit that future biogeomorphic balances will be variable and heterogeneous in time and space. To further unravel future biogeomorphic balances, we propose three new research directions for joint research of mountain geomorphologists and ecologists, using advancing field measurement, remote sensing and modelling techniques. Recognizing high mountains as ‘biogeomorphic ecosystems’ will help to better safeguard mountain infrastructure, lives and livelihoods of millions of people around the world.
{"title":"Go or grow? Feedbacks between moving slopes and shifting plants in high mountain environments","authors":"J. Eichel, M. Stoffel, S. Wipf","doi":"10.1177/03091333231193844","DOIUrl":"https://doi.org/10.1177/03091333231193844","url":null,"abstract":"High mountains are climate change hotspots. Quickly rising temperatures trigger vegetation shifts such as upslope migration, possibly threatening mountain biodiversity. At the same time, mountain slopes are becoming increasingly unstable due to degrading permafrost and changing rain and snowfall regimes, which favour slope movements such as rockfall and debris flows. Slope movements can limit plant colonization, while, at the same time, plant colonization can stabilize moving slopes. Thus, we here propose that response of high mountain environments to climate change depends on a ‘biogeomorphic balance’ between slope movement intensity and the trait-dependent ability of mountain plants to survive and stabilize slopes. We envision three possible scenarios of biogeomorphic balance: (1) Intensifying slope movements limit vegetation shifts and thus amplify instability. (2) Shifting ecosystem engineer species reduce slope movement and facilitate shifts for less movement-adapted species. (3) Trees and tall shrubs shifting on stable slopes limit slope instability but decrease biodiversity. Previous geomorphic, ecological and palaeoecological studies support all three scenarios. Given differences in ecologic and geomorphic response rates to climate change, as well as high environmental heterogeneity and elevational gradients in mountain environments, we posit that future biogeomorphic balances will be variable and heterogeneous in time and space. To further unravel future biogeomorphic balances, we propose three new research directions for joint research of mountain geomorphologists and ecologists, using advancing field measurement, remote sensing and modelling techniques. Recognizing high mountains as ‘biogeomorphic ecosystems’ will help to better safeguard mountain infrastructure, lives and livelihoods of millions of people around the world.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"87 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72814900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-15DOI: 10.1177/03091333231182701
G. Fernandez, Thais Baptista da Rocha, José Maria Landin Dominguez, Sérgio Cadena de Vasconcelos, Gilberto Tavares de Macedo Dias, André da Costa, M. S. Figueiredo, Alberto Garcia Figueiredo Junior, C. Silva, Thiago Gonçalves Pereira, Beatriz Abreu Machado
Souza et al. (2022) based on grain size analyses, Optical Stimulated Luminescence (OSL) ages in fluvial sediments, and regional topography affirmed that most of the Paraiba do Sul River Delta (PSRD) has been deposited during the Little Ice Age (LIA). Souza et al. (2022) also inferred that after the LIA, PSRD presents shoreline erosion, using OSL undetermined results, regional topography, and field photographs, suggesting the direct connection of erosion and human intervention along river basin. As the results obtained by Souza et al. (2022) present several inconsistences about coastal evolution, and question previous works about PDRD developed in the last 30 years, we discuss these in three different sections, covering geological, historical, and recent geomorphological changes in PDRD.
Souza et al.(2022)基于粒度分析、河流沉积物的光学激发发光(OSL)年龄和区域地形，确认了大部分南帕拉伊巴河三角洲(PSRD)是在小冰期(LIA)沉积的。Souza et al.(2022)也利用OSL未确定的结果、区域地形和野外照片推断，在LIA之后，PSRD呈现海岸线侵蚀，表明流域侵蚀与人类干预有直接联系。由于Souza等人(2022)获得的结果在沿海演变方面存在一些不一致之处，并质疑过去30年来关于PDRD的先前工作，我们将在三个不同的部分讨论这些问题，包括PDRD的地质、历史和最近的地貌变化。
{"title":"Comments on Souza et al. (2022) “Recent geomorphological changes in the Paraiba do Sul delta, South America East Coast”","authors":"G. Fernandez, Thais Baptista da Rocha, José Maria Landin Dominguez, Sérgio Cadena de Vasconcelos, Gilberto Tavares de Macedo Dias, André da Costa, M. S. Figueiredo, Alberto Garcia Figueiredo Junior, C. Silva, Thiago Gonçalves Pereira, Beatriz Abreu Machado","doi":"10.1177/03091333231182701","DOIUrl":"https://doi.org/10.1177/03091333231182701","url":null,"abstract":"Souza et al. (2022) based on grain size analyses, Optical Stimulated Luminescence (OSL) ages in fluvial sediments, and regional topography affirmed that most of the Paraiba do Sul River Delta (PSRD) has been deposited during the Little Ice Age (LIA). Souza et al. (2022) also inferred that after the LIA, PSRD presents shoreline erosion, using OSL undetermined results, regional topography, and field photographs, suggesting the direct connection of erosion and human intervention along river basin. As the results obtained by Souza et al. (2022) present several inconsistences about coastal evolution, and question previous works about PDRD developed in the last 30 years, we discuss these in three different sections, covering geological, historical, and recent geomorphological changes in PDRD.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"6 1","pages":"625 - 641"},"PeriodicalIF":3.9,"publicationDate":"2023-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90383672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-14DOI: 10.1177/03091333231189350
Jun Jing, Rui Li, Yushan Zhang, Qinglin Wu
Soil erosion is one of the most serious ecological threats in karst areas of Southwest China. The identification of priority areas for remediation and its driving factors is essential to improving the efficiency of prevention and control. The present study systematically considered natural and socio-economic factors not involved in the revised universal soil loss equation (RUSLE) model, and determined priority areas for soil erosion management based on minimum administrative units and karst landforms. Then, the driving factors were identified by using geographic detector. The results showed that the priority areas were mainly concentrated in the southwest, southeast and northeast, overlapping with the severely eroded areas (Erosion rate=45.79 t·ha−1·a−1). Gradient risk zones had geomorphological differences, but the most eroded zones were all controlled by bedrock exposure rates, elevation, or slope position. The spatial correlation and high erosion rate of priority areas provided opportunities to optimize the efficiency and cost of control. Driving factors were affected by karst landforms. The explanation power of slope position on soil erosion was higher in the peak cluster depressions and karst basins with small undulations ([Formula: see text]), while the karst gorges, trough valleys and plateaus with large undulations gradually decreased ([Formula: see text]). The interaction of driving factors will enhance the explanatory power for soil erosion. Among them, the repetition rate of elevation was 60%, and the repetition rate of lithology and development index was 40%. This study provides useful information for identifying and managing priority areas for soil erosion control, and enriches the theory of soil and water conservation in karst areas.
{"title":"Identification of priority areas for soil erosion control based on minimum administrative units and karst landforms in karst areas of Guizhou","authors":"Jun Jing, Rui Li, Yushan Zhang, Qinglin Wu","doi":"10.1177/03091333231189350","DOIUrl":"https://doi.org/10.1177/03091333231189350","url":null,"abstract":"Soil erosion is one of the most serious ecological threats in karst areas of Southwest China. The identification of priority areas for remediation and its driving factors is essential to improving the efficiency of prevention and control. The present study systematically considered natural and socio-economic factors not involved in the revised universal soil loss equation (RUSLE) model, and determined priority areas for soil erosion management based on minimum administrative units and karst landforms. Then, the driving factors were identified by using geographic detector. The results showed that the priority areas were mainly concentrated in the southwest, southeast and northeast, overlapping with the severely eroded areas (Erosion rate=45.79 t·ha−1·a−1). Gradient risk zones had geomorphological differences, but the most eroded zones were all controlled by bedrock exposure rates, elevation, or slope position. The spatial correlation and high erosion rate of priority areas provided opportunities to optimize the efficiency and cost of control. Driving factors were affected by karst landforms. The explanation power of slope position on soil erosion was higher in the peak cluster depressions and karst basins with small undulations ([Formula: see text]), while the karst gorges, trough valleys and plateaus with large undulations gradually decreased ([Formula: see text]). The interaction of driving factors will enhance the explanatory power for soil erosion. Among them, the repetition rate of elevation was 60%, and the repetition rate of lithology and development index was 40%. This study provides useful information for identifying and managing priority areas for soil erosion control, and enriches the theory of soil and water conservation in karst areas.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"24 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78290330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-13DOI: 10.1177/03091333231187817
Shiyu Li, Ming Zhang, Lunche Wang, Qian Cao, Wenmin Qin
Open biomass burning (OBB) negatively impacts air quality by discharging abundant fine particulate matter (PM2.5, aerodynamic diameter ≤2.5 µm) and trace gases. The statistical methods and numerical simulations have been used to estimate emissions from OBB. The former is poor in producing reliable distributions and transport of emissions, while studies with the latter have focused on cases analysis over short periods. This study investigates the multi-year evaluation of OBB and its contribution to PM2.5 and black carbon (BC) based on satellite observations and numerical modeling over the North China Plain. The number of fires increased by 206% from 2008 to 2012, and decreased by 84% from 2012 to 2016, indicating that the implementation of straw burning ban policy had achieved significant positive effects. The simulation from Weather Research and Forecasting model coupled with chemistry showed that the surface concentrations of PM2.5 and BC emitted by OBB in the burning source area increased from 22 and 3.22 μg/m3, respectively, in 2008 to 45.77 and 6.47 μg/m3, respectively, in 2012, and then decreased to 1.41 and 0.22 μg/m3, respectively, in 2016. The differentiated impacts on air quality of policies across provinces are also investigated. Open crop straw burning was banned early in Shandong and Henan provinces, but they suffer from poor air quality due to open straw burning until the effective straw burning ban in Anhui and Jiangsu provinces, which suggests the need for interregional collaboration for pollution control.
{"title":"The evolution of open biomass burning during summer crop harvest in the North China Plain","authors":"Shiyu Li, Ming Zhang, Lunche Wang, Qian Cao, Wenmin Qin","doi":"10.1177/03091333231187817","DOIUrl":"https://doi.org/10.1177/03091333231187817","url":null,"abstract":"Open biomass burning (OBB) negatively impacts air quality by discharging abundant fine particulate matter (PM2.5, aerodynamic diameter ≤2.5 µm) and trace gases. The statistical methods and numerical simulations have been used to estimate emissions from OBB. The former is poor in producing reliable distributions and transport of emissions, while studies with the latter have focused on cases analysis over short periods. This study investigates the multi-year evaluation of OBB and its contribution to PM2.5 and black carbon (BC) based on satellite observations and numerical modeling over the North China Plain. The number of fires increased by 206% from 2008 to 2012, and decreased by 84% from 2012 to 2016, indicating that the implementation of straw burning ban policy had achieved significant positive effects. The simulation from Weather Research and Forecasting model coupled with chemistry showed that the surface concentrations of PM2.5 and BC emitted by OBB in the burning source area increased from 22 and 3.22 μg/m3, respectively, in 2008 to 45.77 and 6.47 μg/m3, respectively, in 2012, and then decreased to 1.41 and 0.22 μg/m3, respectively, in 2016. The differentiated impacts on air quality of policies across provinces are also investigated. Open crop straw burning was banned early in Shandong and Henan provinces, but they suffer from poor air quality due to open straw burning until the effective straw burning ban in Anhui and Jiangsu provinces, which suggests the need for interregional collaboration for pollution control.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"18 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85135329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-10DOI: 10.1177/03091333231186893
Xuan Gui, Lunche Wang, Qian Cao, Shiyu Li, Weixia Jiang, Shaoqiang Wang
Anthropogenic emissions affect vegetation photosynthesis and carbon flux through meteorological variations induced by aerosols and clouds. However, the insufficient consideration of meteorological conditions limits the understanding of relevant mechanisms, and further inhibits the projection of future terrestrial carbon balance. Based on multiple sets of model simulations, we characterized changes in gross primary production (GPP) due to three typical individual pollutants emissions (black carbon, organic carbon, and sulfate), quantified the relative contributions of co-varied environmental factors, and explored the regulatory roles of background meteorological conditions across China. Our results showed that the heterogeneous GPP enhancement induced by emissions was dominated by cloud cover (CC) change. During its short-term effect, air temperature (Tair), vapor pressure deficit (VPD), and radiation (both quality and quantity) played a collectively non-negligible role in GPP variation, among which the universal diffuse radiation fertilization effect was generally far less than the benefits of brighter, cooler, and wetter environmental conditions. However, the sensitivity of GPP to an individual environmental variable was also altered by background meteorological gradients, whose changing pattern differed substantially among factors, indicating that the meteorological-regulated vegetation optimal photosynthetic range was a trade-off among heat, water, and light instead of being controlled by the univariable. This study implies that a deeper understanding of concurrent environmental variables is an effective way to reduce uncertainties in assessing the terrestrial carbon cycle perturbation exerted by human-induced emissions, especially under future scenarios with ongoing climate change.
{"title":"The roles of environmental conditions in the pollutant emission-induced gross primary production change: Co-contribution of meteorological fields and regulation of its background gradients","authors":"Xuan Gui, Lunche Wang, Qian Cao, Shiyu Li, Weixia Jiang, Shaoqiang Wang","doi":"10.1177/03091333231186893","DOIUrl":"https://doi.org/10.1177/03091333231186893","url":null,"abstract":"Anthropogenic emissions affect vegetation photosynthesis and carbon flux through meteorological variations induced by aerosols and clouds. However, the insufficient consideration of meteorological conditions limits the understanding of relevant mechanisms, and further inhibits the projection of future terrestrial carbon balance. Based on multiple sets of model simulations, we characterized changes in gross primary production (GPP) due to three typical individual pollutants emissions (black carbon, organic carbon, and sulfate), quantified the relative contributions of co-varied environmental factors, and explored the regulatory roles of background meteorological conditions across China. Our results showed that the heterogeneous GPP enhancement induced by emissions was dominated by cloud cover (CC) change. During its short-term effect, air temperature (Tair), vapor pressure deficit (VPD), and radiation (both quality and quantity) played a collectively non-negligible role in GPP variation, among which the universal diffuse radiation fertilization effect was generally far less than the benefits of brighter, cooler, and wetter environmental conditions. However, the sensitivity of GPP to an individual environmental variable was also altered by background meteorological gradients, whose changing pattern differed substantially among factors, indicating that the meteorological-regulated vegetation optimal photosynthetic range was a trade-off among heat, water, and light instead of being controlled by the univariable. This study implies that a deeper understanding of concurrent environmental variables is an effective way to reduce uncertainties in assessing the terrestrial carbon cycle perturbation exerted by human-induced emissions, especially under future scenarios with ongoing climate change.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"96 1","pages":""},"PeriodicalIF":3.9,"publicationDate":"2023-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75938819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-07-07DOI: 10.1177/03091333231187619
S. T. Kalathil, V. Chandra
Hydraulic considerations specific for the design of step-pool nature-like fishways (NLFs) are limited to the body dimensions of the target species. Additional hydraulic criteria for flow depth, maximum values for each of pool depth, velocity, and turbulent kinetic energy in terms of the weir opening width and discharge can help design an optimum step-pool NLF. The present study developed design charts and rating curves based on numerical modeling using the computational fluid dynamics software FLOW-3D® HYDRO. Instantaneous velocity measurements on a 1:4 scaled physical model of a step-pool nature-like fishway designed as per the available design guidelines have been used to validate the numerical model. The hydrodynamics of the fishway with respect to the weir opening ratio b r (0.10, 0.25, 0.45, 0.65, and 1.00) and discharge Q (0.1–1.5 m3/s) was analyzed through numerical simulations on a prototype scale. The simulation results showed that the maximum flow velocity and the averaged velocity over the crest at b r = 0.10 and 0.25 are considerably lower than at b r > 0.25. The maximum turbulent kinetic energy and energy dissipation factors for the tested range of discharges were within recommended limits for b r = 0.10 and 0.25. The present study outcome in terms of the design charts and rating curves that illustrate the relationship between different variables can be used for an optimum design and ease in field implementation. In addition, the bed structure of the step-pool NLF presented in this study can be used to recreate full-scale or pilot models.
设计阶梯池类自然鱼道(NLFs)的水力考虑仅限于目标物种的身体尺寸。水流深度、池深、流速和湍流动能(堰口宽度和流量)的最大值等附加水力标准可以帮助设计最佳的阶梯池NLF。本研究利用计算流体动力学软件FLOW-3D®HYDRO建立了基于数值建模的设计图表和评级曲线。在1:4比例的阶梯池自然鱼道物理模型上的瞬时速度测量已被用于验证数值模型，该模型是根据现有的设计准则设计的。通过原型尺度上的数值模拟，分析了鱼道的水动力学特性与堰开比b r(0.10、0.25、0.45、0.65和1.00)和流量Q (0.1 ~ 1.5 m3/s)的关系。模拟结果表明，在b r = 0.10和0.25时，最大流速和平均流速明显低于b r > 0.25时。试验放电范围内的最大湍流动能和能量耗散因子均在推荐范围内(b r = 0.10和0.25)。目前的研究结果在设计图表和评级曲线方面说明了不同变量之间的关系，可以用于优化设计和易于现场实施。此外，本研究中提出的阶梯池NLF的床层结构可用于重建全尺寸或中试模型。
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Pub Date : 2023-06-12DOI: 10.1177/03091333231182699
Andreoli de Souza, L. Lämmle, A. Perez Filho, C. Donadio
Scientific knowledge advances by the discussions on hypotheses, methods, and results, wherein the contradictory plays a positive role developing new theoretical-methodological approaches. In a positive debate to the progress of the science, the agreements and disagreements must only permeate the scientific scope and based on ethics to be away from the conflicts of interest. From this perspective, after knowing the submission titled Comments on Souza et al. (2022) “Recent geomorphological changes in the Paraiba do Sul delta, South America East Coast” to the journal Progress in Physical Geography: Earth and Environment (PPG), which addressed several issues concerning the results published in that article, we wrote this response to clarify the doubts related to the original paper. The comment’s authors focus mainly on da Rocha et al. (2019), a locally published article that did not fully encompass the complexity of processes and geomorphological dynamics related to the delta evolution. Furthermore, it did not present the parameters used in the geochronological analyses in accordance with the international literature. Finally, the discussions presented in the original article contribute to advances in knowledge about the responses of the Paraíba do Sul delta to the Little Ice Age.
科学知识通过对假设、方法和结果的讨论而进步，其中的矛盾在发展新的理论方法方法方面起着积极的作用。在对科学进步的积极辩论中，同意和分歧必须渗透到科学的范围内，并以伦理为基础，远离利益冲突。从这个角度来看，在了解了题为“评论Souza et al.(2022)“南美洲东海岸Paraiba do Sul三角洲近期地貌变化”的论文提交给《自然地理进展:地球与环境》(PPG)杂志后，我们写了这篇回应，以澄清与该文章发表的结果有关的几个问题。该评论的作者主要关注da Rocha等人(2019)，这是一篇在当地发表的文章，并未完全涵盖与三角洲演化相关的过程和地貌动力学的复杂性。此外，它没有根据国际文献提出地质年代学分析中使用的参数。最后，原文中提出的讨论有助于提高对Paraíba do Sul三角洲对小冰期的反应的认识。
{"title":"Reply to the comments on Souza et al. (2022) “Recent geomorphological changes in the Paraiba do Sul delta, South America East Coast”","authors":"Andreoli de Souza, L. Lämmle, A. Perez Filho, C. Donadio","doi":"10.1177/03091333231182699","DOIUrl":"https://doi.org/10.1177/03091333231182699","url":null,"abstract":"Scientific knowledge advances by the discussions on hypotheses, methods, and results, wherein the contradictory plays a positive role developing new theoretical-methodological approaches. In a positive debate to the progress of the science, the agreements and disagreements must only permeate the scientific scope and based on ethics to be away from the conflicts of interest. From this perspective, after knowing the submission titled Comments on Souza et al. (2022) “Recent geomorphological changes in the Paraiba do Sul delta, South America East Coast” to the journal Progress in Physical Geography: Earth and Environment (PPG), which addressed several issues concerning the results published in that article, we wrote this response to clarify the doubts related to the original paper. The comment’s authors focus mainly on da Rocha et al. (2019), a locally published article that did not fully encompass the complexity of processes and geomorphological dynamics related to the delta evolution. Furthermore, it did not present the parameters used in the geochronological analyses in accordance with the international literature. Finally, the discussions presented in the original article contribute to advances in knowledge about the responses of the Paraíba do Sul delta to the Little Ice Age.","PeriodicalId":49659,"journal":{"name":"Progress in Physical Geography-Earth and Environment","volume":"1 1","pages":"642 - 651"},"PeriodicalIF":3.9,"publicationDate":"2023-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75865488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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