Remote sensing of water use and water stress in the African Savanna ecosystem at local scale – development and validation of a monitoring tool.
In this study we develop a mechanism for monitoring the water used by African savanna from fine scale (meters) to watershed scale, integrating the effects of the water stress. Our hypothesis is that the Ecosystem Stress Index (ESI) is a valuable tool to downscale estimates of actual evapotranspiration at coarse scale, to high resolutions. To monitor savanna water fluxes in a semi-continuous way this study integrates two different ET-estimation approaches: KC-FAO56 model, integrating reflectance-based “crop” coefficients (SPOT 4 & 5 satellites), is used to derive unstressed savanna evapotranspiration (with h...
Source: Physics and Chemistry of the Earth, Parts ABC - February 6, 2019 Category: Science Source Type: research

Characterization of rice agriculture in the Southern Province of Rwanda by means of microwave remote sensing
The objective our study is to contribute to this effort by using spaceborne Synthetic Aperture Radar (SAR) data to retrieve phenological parameters of paddy rice in the Southern Province of Rwanda. High spatial resolution dual polarized Sentinel-1 SAR data were obtained for the time period covering Season B of the two rice cropping seasons of 2017. For the derivation of the selected phenological indicators (start, end, middle and length of season) time series analysis was performed. Based on the temporal pattern of radar backscatter values, the temporal and spatial distribution of SAR derived phenological indicators consid...
Source: Physics and Chemistry of the Earth, Parts ABC - February 5, 2019 Category: Science Source Type: research

Assessing the potential of Sentinel-2 MSI sensor in detecting and mapping the spatial distribution of gullies in a communal grazing landscape
In this study, we evaluate the potential of the recently launched Sentinel-2 MSI multispectral sensor in mapping the spatial distribution of gullies in Okhombe valley, KwaZulu-Natal, South Africa. The study further investigates possible environmental factors that contribute towards gully initiation and development. Analysis was done using a robust machine learning algorithm: Support Vector Machine (SVM). Additionally, possible environmental factors (i.e. slope steepness, percent vegetation cover, and Topographic Wetness Index, Stream Power Index, and hillslope profile and planform curvature) that could have an influence on...
Source: Physics and Chemistry of the Earth, Parts ABC - February 5, 2019 Category: Science Source Type: research

Quantitative analysis of phenols and PAHs in the Nandoni Dam in Limpopo Province, South Africa: a preliminary study for dam water quality management
Publication date: Available online 5 February 2019Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Lebea N. Nthunya, Nomcebo P. Khumalo, Arne R. Verliefde, Bhekie B. Mamba, Sabelo D. MhlangaAbstractThis paper assesses the level of phenols and polycyclic aromatic hydrocarbons (PAHs) in the Nandoni dam situated in the Vhembe District, Limpopo Province, South Africa. About 55 villages are supplied with water sourced from the dam which is prone to contamination by different pollutants other than phenols and PAHs, due to its exposure to agricultural, human and animal activities around it. A quantitative determi...
Source: Physics and Chemistry of the Earth, Parts ABC - February 5, 2019 Category: Science Source Type: research

Strategies FOR Coping and Adapting to flooDing AND their DETERMINANTS: A comparative study of cases from Namibia and Zambia
This study seeks to inform decision-makers and practitioners on how the disaster risks can be reduced and managed in the similar environments of the two countries, and to inform them of the status quo of flood adaptation. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - February 2, 2019 Category: Science Source Type: research

Localised human thermal discomfort assessment using high temporal resolution meteorological data: A case of University of Zimbabwe.
This study investigated the thermal discomfort patterns at the University of Zimbabwe in Harare, Zimbabwe; paying attention to the outdoor and indoor seasonal and diurnal variations. Temperature and relative humidity data from an automatic weather station located in the study area was incorporated into the temperature humidity index to retrieve outdoor human thermal discomfort patterns. Based on data availability, air temperature and humidity hourly data for the period 2014 to 2017 was used. The indoor human thermal discomfort patterns were then obtained using the linear relationship between outdoor temperatures and indoor...
Source: Physics and Chemistry of the Earth, Parts ABC - January 26, 2019 Category: Science Source Type: research

Sensitivity Analysis and Optimum Design of a Hydronic Snow Melting System During Snowfall
Publication date: Available online 18 January 2019Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Hongwei Liu, Pooneh Maghoul, Hartmut M. HolländerAbstractSnow and ice accumulation induces hazardous driving conditions due to the effect of reduced friction on the road surface. A traditional chemical-based snow melting approach is not environmentally friendly and effective when the temperature is below −3.9∘ C. Thermal snow melting techniques, such as hydronic heating system, can be an alternative to chemical-based methods. In this paper, a new approach is proposed for sizing the hydronic snow ...
Source: Physics and Chemistry of the Earth, Parts ABC - January 20, 2019 Category: Science Source Type: research

The higher, the cooler? Effects of building height on land surface temperatures in residential areas of Beijing
This study aims to fill this gap. We focused on the residential landscapes in the central area of Beijing, and quantified the relationships between the vertical structure of buildings and LST. We delineated the boundaries of residential neighborhoods based on high resolution imagery, which were latterly used as the unit of statistical analysis. Building height, and proportional cover of buildings and vegetation were also mapped from high resolution imagery, with aid of digital maps. LST was retrieved from thermal band of TM imagery. We used Pearson correlation, partial correlation and ordinary least squares(OLS) regression...
Source: Physics and Chemistry of the Earth, Parts ABC - January 18, 2019 Category: Science Source Type: research

Mapping spatiotemporal variations of CO2 (carbon dioxide) emissions using nighttime light data in Guangdong Province
This study corrected inconsistency and uncontinuity of nighttime light (NTL) data based on stable light value pixels, and performed a distribute model of CO2 emissions in Guangdong province during the period of 2005 to 2013. The model results clearly showed the spatial and temporal variations of CO2 emissions during 2005–2013 in Guangdong, with the Pearl River Delta region contributing the highest CO2 emissions. These results are relevant to understanding the spatiotemporal CO2 emission dynamics at a county level and establishing policies for carbon emission mitigation. This research highlights the importance of spat...
Source: Physics and Chemistry of the Earth, Parts ABC - January 18, 2019 Category: Science Source Type: research

Numerical study of a local PM2.5 pollution event under the typhoon Neoguri (1408) background over a coastal metropolitan city, Shenzhen, China
This study demonstrated that air pollution can form over Shenzhen under the typhoon background, and the complex interaction between typhoon circulations and sea breezes development controls the spatiotemporal distribution of the air pollution in the coastal metropolitan city. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - January 16, 2019 Category: Science Source Type: research

Remote sensing equivalent water thickness of grass treated with different fertiliser regimes using resample HyspIRI and EnMAP data
Publication date: Available online 11 January 2019Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Mbulisi Sibanda, Onisimo Mutanga, Timothy Dube, Mologadi C. Mothapo, Paramu L. MafongoyaAbstractThe aim of this study was to test the spectral settings of the forthcoming EnMAP and HyspIRI hyperspectral imagers in estimating equivalent water thickness of native grass grown under different management practices, using two regression ensembles (partial least squares regression (PLSR) and sparse partial least squares regression (SPLSR). Results showed that the HyspIRI spectral settings better characterised Equiva...
Source: Physics and Chemistry of the Earth, Parts ABC - January 11, 2019 Category: Science Source Type: research

An ecosystem services value assessment of land-use change in Chengdu: Based on a modification of scarcity factor
Publication date: Available online 7 January 2019Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Yu Kang, Chuanxing Cheng, Xianghua Liu, Fan Zhang, Zhihui Li, Siqi LuAbstractChanges in land-use, caused by rapid urbanization, lead to changes in the supply and demand for ecosystem services. Significant research has been conducted to investigate the impact of changes in the physical supply of ecosystem services on their value. However, quantifying the effects of simultaneous changes in supply and demand on the scarcity value of ecosystem services can provides a more reasonable assessment of ecosystem service...
Source: Physics and Chemistry of the Earth, Parts ABC - January 8, 2019 Category: Science Source Type: research

Soil Salinity Mapping in Everglades National Park Using Remote Sensing Techniques and Vegetation Salt Tolerance
In this study, spatio-temporal soil salinity maps are created using remote sensing techniques, coupled with literature review to understand vegetation salt tolerance properties, and field assessments entailing insitu electric conductivity (EC) measurements. The mapping first entailed the execution of a supervised machine learning technique—the maximum likelihood classification algorithm—to delineate seven vegetation-based land cover classes for the area, namely, mangrove forest, mangrove scrub, low-density forest, sawgrass, prairies and marshes, barren lands with woodland hammock and water, for the years 1996, ...
Source: Physics and Chemistry of the Earth, Parts ABC - January 7, 2019 Category: Science Source Type: research

Remote sensing image-based analysis of the urban heat island effect in Shenzhen, China
This study helps to better understand the optimization of urban landscapes and alleviation of the urban heat island effect. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - January 7, 2019 Category: Science Source Type: research

The complex interaction controls the spatiotemporal distribution of the air pollution Numerical study of a local PM2.5 pollution event under the typhoon Neoguri (1408) background over a coastal metropolitan city, Shenzhen, China
This study demonstrated that air pollution can form over Shenzhen under the typhoon background, and the complex interaction between typhoon circulations and sea breeze development controls the spatiotemporal distribution of the air pollution in the coastal metropolitan city. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - January 7, 2019 Category: Science Source Type: research

Spatial-temporal Pattern and Driving Factors of Wastewater Discharge in Yangtze River Economic Zone
This study uses Exploratory Spatial Data Analysis (ESDA) method and Logarithmic Mean Divisia Index (LMDI) model to analyze the Spatial-temporal pattern of industrial wastewater and discuss the dominant driving factors of industrial wastewater discharge in Yangtze River Economic Zone from 2002 to 2013.The study indicates that: (1) In terms of the spatial- temporal pattern, the wastewater discharge of Yangtze River Economic Zone first increased from 2002 to 2015 and then decreased after reaching the peak in 2005. Referring to the characteristic of spatial, the wastewater discharge increases from upstream to downstream. There...
Source: Physics and Chemistry of the Earth, Parts ABC - January 7, 2019 Category: Science Source Type: research

Impacts of land use and land cover changes on hydrology of the Gumara catchment, Ethiopia
This study quantifies the rate of LULC in the Gumara catchment (1,413 km2), an important tributary to Lake Tana in northwest Ethiopia. Landsat images of three years (1986, 2001 and 2015) were processed using the supervised classification method. An extensive field survey generated over 150 ground truth points, which were used in the classification and accuracy assessment process. Then, a conceptual rainfall-runoff model (HBV) was calibrated and validated to assess the impacts of LULC changes on water balance components - evapotranspiration, soil moisture, groundwater recharge and runoff. Additionally, the decadal means and...
Source: Physics and Chemistry of the Earth, Parts ABC - January 7, 2019 Category: Science Source Type: research

Assessment of lake surface dynamics using satellite imagery and in-situ data; case of Lake Ngami in North-West Botswana
Publication date: Available online 3 January 2019Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Leokeditswe Mokgedi, Joel Nobert, Subira MunishiAbstractThe understanding of surface dynamics of Lake Ngami, a part of Okavango river system is hindered by paucity of data. The aim of this study was to assess the lake surface dynamics using satellite imagery and in-situ data.Surface dynamics of Lake Ngami were monitored using remote sensing methods to complement the available inadequate in-situ measurements. Landsat imagery of the year 1979 to year 2016 were used. The Lake boundary was mapped using the Modifie...
Source: Physics and Chemistry of the Earth, Parts ABC - January 4, 2019 Category: Science Source Type: research

The impacts of commercial plantation forests on groundwater recharge: A case study from George (Western Cape, South Africa)
This study sought to contribute to addressing this important knowledge gap. The main objective was to compare groundwater recharge dynamics in commercial plantation forests and co-occurring indigenous forests. The HYDRUS-2D model was used to simulate the hillslope hydrological dynamics along 3 study transects, i.e. a Pinus radiata transect, a Pinus elliotii transect and in the Groenkop indigenous forest, during the period 1 October 2016 to 30 September 2017. The model was used to simulate the interaction between the vegetation, unsaturated zone and the saturated zone in order to better understand the groundwater recharge d...
Source: Physics and Chemistry of the Earth, Parts ABC - December 22, 2018 Category: Science Source Type: research

Combining a thermal tracer with a transport model to estimate shallow flow velocities
Publication date: Available online 21 December 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): João R.C.B. Abrantes, Rodrigo B. Moruzzi, João L.M.P. de Lima, Alexandre Silveira, Abelardo A.A. MontenegroAbstract:For a long time, tracer techniques based on dyes, salts and more recently heat have been used to estimate shallow flow velocities. Traditionally, flow velocity estimation using tracers would consist of tracking the movement of the leading edge or the centroid of the tracer with the flow. An alternative methodology uses an analytical solution of an advection–dispersion transp...
Source: Physics and Chemistry of the Earth, Parts ABC - December 22, 2018 Category: Science Source Type: research

Prediction of future climate in Ngerengere river catchment, Tanzania
In this study, one of the protocols for downscaling climate variables from coarse Global Circulation Models (GCM), the Long Ashton Research Station Weather Generator (LARS-WG) was applied in the Ngerengere catchment in Tanzania. LARS-WG is a stochastic weather generator which can be used for generation of weather data at single site under both current and future climate condition.The LARS-WG model was calibrated and validated using the observed daily rainfall data for the period 1971-2000 (30 years) in Ngerengere catchment. LARS-WG calibration results indicate a good fit between observed and generated average daily rainfal...
Source: Physics and Chemistry of the Earth, Parts ABC - December 20, 2018 Category: Science Source Type: research

An Automatic Traffic Density Estimation Using Single Shot Detection (SSD) and MobileNet-SSD
In this study, we show a key application area for the SSD and MobileNet-SSD framework. The advantages and shortcomings of the SSD and MobileNet-SSD framework were analyzed using fifty-nine individual traffic cameras. In addition, we compared the two algorithms with manually estimated density. The SSD framework shows significant potential in the field of traffic density estimation. SSD achieved 92.97% average detection accuracy in our experiment. On the other hand, the MobileNet-SSD achieved 79.30% average detection accuracy. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - December 19, 2018 Category: Science Source Type: research

Advancements in satellite remote sensing for mapping and monitoring of Alien Invasive Plant species (AIPs)
Publication date: Available online 18 December 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Lwando Royimani, Onisimo Mutanga, John Odindi, Timothy Dube, Trylee Nyasha MatongeraAbstractDetecting and mapping the occurrence, spatial distribution and abundance of Alien Invasive Plants (AIPs) have recently gained substantial attention, globally. This work, therefore, provides an overview of advancements in satellite remote sensing for mapping and monitoring of AIPs and associated challenges and opportunities. Satellite remote sensing techniques have been successful in detecting and mapping the spatial a...
Source: Physics and Chemistry of the Earth, Parts ABC - December 19, 2018 Category: Science Source Type: research

Evaluation of the adsorptive properties of locally available alumino-silicate clay in As(III) and As(V) remediation from groundwater
This study evaluates the adsorptive properties of locally available alumino-silicate clay in removal of As(III) and As(V) from groundwater. Physicochemical properties of the clay were characterized using x-ray diffraction (XRD), x-ray fluorescence (XRF), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. Batch adsorption experiments were conducted to evaluate the effectiveness of the alumino-silicate clay in the removal of As(III) and As(V) under various conditions of contact time, adsorbent dosage, initial adsorbate concentration and initial pH. The results showed that adsorp...
Source: Physics and Chemistry of the Earth, Parts ABC - December 4, 2018 Category: Science Source Type: research

Detection of soil moisture anomalies based on Sentinel-1
Publication date: Available online 30 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Felix Greifeneder, Erick Khamala, Degelo Sendabo, Wolfgang Wagner, Marc Zebisch, Hussein Farah, Claudia NotarnicolaAbstractActive and passive microwave remote sensing has evolved into a well-accepted and widely used method for the spatially continuous, coarse to medium resolution mapping of the surface soil moisture content (SMC). Presently, the exploitation of high-resolution data is less mature. Sentinel-1 is a high-resolution Synthetic Aperture Radar (∼5 by 20 m), which acts as the basis for mapping o...
Source: Physics and Chemistry of the Earth, Parts ABC - December 1, 2018 Category: Science Source Type: research

Spatial-temporal evolution of urban heat Island in Xi'an from 2006 to 2016
Publication date: Available online 22 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Suhua Liu, Zhenfeng Zang, Wenchuan Wang, Yueru WuAbstractDuring the rapid development of urbanization, the urban heat island (UHI), becomes one of the major urbanization progress problems that affects the environmental, social and ecology profoundly. Analyzing the UHI can help understanding the UHI status and the physical characteristics of cities, and is significant to provide ecosystem management plans and mitigation strategies for the UHI. By utilizing the MODIS LST products, Landsat series data and the e...
Source: Physics and Chemistry of the Earth, Parts ABC - November 30, 2018 Category: Science Source Type: research

Editorial Board
Publication date: December 2018Source: Physics and Chemistry of the Earth, Parts A/B/C, Volume 108Author(s): (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - November 30, 2018 Category: Science Source Type: research

Editorial Board
Publication date: October 2018Source: Physics and Chemistry of the Earth, Parts A/B/C, Volume 107Author(s): (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - November 23, 2018 Category: Science Source Type: research

The relationship between soil emissivity and soil reflectance under the effects of soil water content
Publication date: Available online 22 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Jing Tian, Shangkun Song, Honglin HeAbstractSignificant changes of surface emissivity have taken place in cities with the rapid urbanization. Surface emissivity influences the radiation budget and the surface energy balance, thereby influences city climate. It is an important parameter in retrieving surface temperature and has close relationship with city heat island effect. This paper attempts to explore the possibility of using soil moisture index (SMI) to estimate soil emissivity (SE). The advantage of us...
Source: Physics and Chemistry of the Earth, Parts ABC - November 22, 2018 Category: Science Source Type: research

Spatial-temporal Evolution of Urban Heat Island in Xi’an from 2006 to 2016
Publication date: Available online 22 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Suhua Liu, Zhenfeng Zang, Wenchuan Wang, Yueru WuAbstractDuring the rapid development of urbanization, the urban heat island (UHI), becomes one of the major urbanization progress problems that affects the environmental, social and ecology profoundly. Analyzing the UHI can help understanding the UHI status and the physical characteristics of cities, and is significant to provide ecosystem management plans and mitigation strategies for the UHI. By utilizing the MODIS LST products, Landsat series data and the e...
Source: Physics and Chemistry of the Earth, Parts ABC - November 22, 2018 Category: Science Source Type: research

Human activities and urban air pollution in Chinese mega city: An insight of ozone weekend effect in Beijing
This study explores the different characteristics of ozone and ozone weekend effect (OWE) in different seasons in places (e.g. urban center, inner urban areas, suburban areas and natural background areas) with different degree of urbanization and intensity of human activities and the effect of urbanization on ozone at different scales in Beijing. The annual daily average ozone concentration in Beijing was 56μg/ m3, with the maximum of 98.0μg/m3 occurred in summer and the minimum of 27μg/m3 in winter. Spatially, annual daily average ozone concentration increased along the urban-rural gradient. The annual ozone conc...
Source: Physics and Chemistry of the Earth, Parts ABC - November 22, 2018 Category: Science Source Type: research

Large-Eddy and Wall-Modelled Simulations of Turbulent Flow over Two-Dimensional River Dunes
Publication date: Available online 17 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Mojtaba Mellati Nokhandan, Ugo Piomelli, Mohammad OmidyeganehAbstractTurbulence models based on the Spalart-Allmaras Detached-Eddy Simulation (DES) approach are used to compute the turbulent flow over a two-dimensional dune geometry. DES was developed for massively separated flows, but has been applied as a wall model to attached flows as well. In attached shear layers, however, the lack of resolved eddies in the region where the model switches from a turbulence model to a Subfilter-Scale (SFS) one, results ...
Source: Physics and Chemistry of the Earth, Parts ABC - November 17, 2018 Category: Science Source Type: research

Difficult roads leading to beautiful destinations? Articulating land Reform's contribution to rural livelihoods in the Limpopo Province, South Africa
This study deployed qualitative research methodologies to gather both secondary and empirical data that enabled analysis of the extent to which the land reform program has contributed to the livelihoods of small-scale emerging farmers in the surroundings of Bela-Bela Municipal Area, Limpopo Province. The study found out that financial resources are a big challenge, with most of the farmers being unable to raise the capital needed to invest in the farming enterprise. In addition, most of the ‘emerging farmers’ do not have the know-how and experience needed to run a commercial farm. Overall, the study enabled us ...
Source: Physics and Chemistry of the Earth, Parts ABC - November 16, 2018 Category: Science Source Type: research

Assessing the functional and operational relationships between the water control infrastructure and water governance: A case of Tugela Ferry Irrigation Scheme and Mooi River Irrigation Scheme in KwaZulu-Natal, South Africa
This study uses a fuzzy model to establish a link between water control infrastructure, i.e., its characteristics, operational requirements, on one hand, and the existing water governance frameworks in the respective irrigation schemes, on the other. The approach was based on Fuzzy Analytical Hierarchy Process (FAHP) and Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (FTOPSIS). The FAHP techniques was used to determine the fuzzy weight of the water control infrastructure aspects and the FTOPSIS was used to rank the water governance aspects, i.e., institutions, processes, procedures, rules and regul...
Source: Physics and Chemistry of the Earth, Parts ABC - November 14, 2018 Category: Science Source Type: research

Difficult Roads Leading to Beautiful Destinations? Articulating Land Reform’s Contribution to Rural Livelihoods in the Limpopo Province, South Africa
This study deployed qualitative research methodologies to gather both secondary and empirical data that enabled analysis of the extent to which the land reform program has contributed to the livelihoods of small-scale emerging farmers in the surroundings of Bela-Bela Municipal Area, Limpopo Province. The study found out that financial resources are a big challenge, with most of the farmers being unable to raise the capital needed to invest in the farming enterprise. In addition, most of the ‘emerging farmers’ do not have the know-how and experience needed to run a commercial farm. Overall, the study enabled us ...
Source: Physics and Chemistry of the Earth, Parts ABC - November 9, 2018 Category: Science Source Type: research

Spatiotemporal variation of heat fluxes in Beijing with land use change from 1997 to 2017
Publication date: Available online 9 November 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Menghui Guo, Shaohui Chen, Weimin Wang, Hong Liang, Guibin Hao, Kai LiuAbstractIt is meaningful to explore the influence of land use change on urban thermal environment for urban sustainable development and city livability improvement etc. Based on one pixel component arranging comparing algorithm (PCACA), this study estimates three instantaneous heat fluxes of Beijing city from meteorological data and the NDVI, land surface temperature (LST), and albedo products retrieved from Landsat data on September 21, 1...
Source: Physics and Chemistry of the Earth, Parts ABC - November 9, 2018 Category: Science Source Type: research

Application of 1D–2D Coupled Modeling in Water Quality Assessment: A Case Study in Ca Mau Peninsula, Vietnam
This study calibrates and validates 1D and 2D models during the dry and flood seasons for 2014 and 2015, as well as assesses water quality in coastal estuaries during the dry and flood season of 2016 by using a 2D model. The calibration and validation results of the hydrodynamic 1D and 2D models show that there is a high degree of conformity regarding the phase and amplitude of water level at observing stations with mean absolute error (MAE) ranges from 0.05 m to 0.37 m. The RMSE–observation standard deviation ratio (RSR) vary from 0.12 to 0.64, and the percent bias (PBIAS) is from –8.9% to 3.2%. Calibration an...
Source: Physics and Chemistry of the Earth, Parts ABC - October 31, 2018 Category: Science Source Type: research

Recent advances in the numerical simulation of rough-wall boundary layers
Publication date: Available online 30 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Ugo PiomelliAbstractTurbulent flows over rough surfaces are ubiquitous in nature and in man-made devices. They present many unique aspects, as roughness alters the turbulence structure and the momentum and energy transfer mechanisms. Numerical simulations that resolve the roughness sublayer are computationally demanding: for an accurate calculation of a flow in realistic conditions, such as the flow in a hydraulic turbine, or over terrain, the roughness should be much smaller than the boundary layer height, a...
Source: Physics and Chemistry of the Earth, Parts ABC - October 30, 2018 Category: Science Source Type: research

Horizontal landfill gas wells: Geometry, physics of flow and connection with the atmosphere
This study addresses gas flow induced by perforated horizontal wells commonly used for landfill gas collection. Planar flow through a porous medium of varying properties is solved numerically, yielding a twofold insight: quantitative deviations establish the validity and limitations of theoretical models, whilst qualitative comparison illustrates the impact of various flow parameters. It is found that an accurate modelling of geometry and medium resistance is essential in determination of a correct pressure distribution that can then be used to optimise gas collection. Gravity, an often overlooked effect, is shown to be no...
Source: Physics and Chemistry of the Earth, Parts ABC - October 29, 2018 Category: Science Source Type: research

Establishing the link between urban land cover change and the proliferation of aquatic hyacinth (Eichhornia crassipes) in Harare Metropolitan, Zimbabwe
Publication date: Available online 17 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Timothy Dube, Mbulisi Sibanda, Victor Bangamwabo, Cletah ShokoAbstractUrban growth is a key process affecting the functioning of natural ecosystems, and consequently the global land-surface process. This work aimed at establishing the link between land cover changes around Harare Metropolitan city and the proliferation of aquatic hyacinth (Eichhornia crassipes) in Lake Chivero. Remotely sensed Landsat series acquired in the year 1973, 1981, 1994, 1998, 2008, 2009 and 2014 was used. Image classification was im...
Source: Physics and Chemistry of the Earth, Parts ABC - October 23, 2018 Category: Science Source Type: research

A comparative assessment of water use by Acacia longifolia invasions occurring on hillslopes and riparian zones in the Cape Agulhas region of South Africa.
Publication date: Available online 19 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Y.P. Mkunyana, D. Mazvimavi, S. Dzikiti, Z. NtshidiAbstractThe detrimental impacts of invasive alien plants on ecosystems and water resources have raised concerns in arid and semi-arid countries like South Africa where the average precipitation is approximately 500 mm/yr, which is below the world average of around 860 mm/yr. Several studies have examined the effects of invasive alien plants such as the Australian Acacias on the water resources. However, few studies have quantified the differences in water use...
Source: Physics and Chemistry of the Earth, Parts ABC - October 20, 2018 Category: Science Source Type: research

Editorial Board
Publication date: August 2018Source: Physics and Chemistry of the Earth, Parts A/B/C, Volume 106Author(s): (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - October 17, 2018 Category: Science Source Type: research

Mapping urban land cover changes and the proliferation of aquatic hyacinth (Eichhornia crassipes) over time
Publication date: Available online 17 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Dube Timothy, Sibanda Mbulisi, Victor Bangamwabo, Cletah ShokoAbstractThis work aimed at mapping land cover changes around Harare and the proliferation of aquatic hyacinth (Eichhornia crassipes) in the Lake Chivero over time. Remotely sensed Landsat series acquired in the year1973, 1981, 1994, 1998, 2008, 2009 and 2014 was used. Image classification was implemented to map the associated changes over time suing discriminant analysis algorithm. The derived thematic maps showed that agricultural land increased f...
Source: Physics and Chemistry of the Earth, Parts ABC - October 17, 2018 Category: Science Source Type: research

Treatment efficiency of fish processing wastewater in different types of biological reactors
Publication date: Available online 5 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Agata Nowak, Robert Mazur, Ewa Panek, Ewa Dacewicz, Krzysztof ChmielowskiAbstractFish processing technologies generate a significant amount of organic waste, both solid and liquid. Fish wastewater (FWW), if untreated or ineffectively treated, poses a threat to the aquatic environment.We investigated efficiency of different types of bioreactors with fixed and moving beds in the treatment of wastewater from fish processing. Pollution levels in raw effluents reached 260-660 mg O2 · dm-3 for BOD5, 450-950 m...
Source: Physics and Chemistry of the Earth, Parts ABC - October 6, 2018 Category: Science Source Type: research

Determination of Nitrate Retention Capacity of Kalahari Sands Using a Permeameter: Case Study of Mashare Farm Soil in the Okavango River Basin
Publication date: Available online 4 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Andrea Vushe, Mbadhi HertaAbstractNamibian irrigators in Okavango River basin use high application rates of N fertilizers on Kalahari sandy soils which may leach nitrates and pollute water resources. The capacity of the sandy soils to retain the nitrates against leaching conditions of prolonged water saturation is not well understood. Therefore, in this study the sandy soil was tested for nitrate leaching rate and retention capacity using a constant head permeability meter in laboratory experiments. Eight samp...
Source: Physics and Chemistry of the Earth, Parts ABC - October 6, 2018 Category: Science Source Type: research

Spatial and temporal analysis of carbon sources and sinks through land use/cover changes in the Beijing-Tianjin-Hebei urban agglomeration region
Publication date: Available online 4 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Xiaolin Cui, Xiaoqing Wei, Wei Liu, Fan Zhang, Zhihui LiAbstractGlobal warming caused by carbon emissions have been recognized as a threat to social health and ecological security. Through matching the relationship between land use types and carbon emissions, based on land use and socio-economic data, this paper uses the emission factor method proposed by IPCC to investigate carbon sources and sinks, as well as validation through land use and land cover change analysis in the Beijing-Tianjin-Hebei (BTH) urban ...
Source: Physics and Chemistry of the Earth, Parts ABC - October 6, 2018 Category: Science Source Type: research

Gullies mitigation and control measures: a case study of the Seirós gullies (North of Portugal)
Publication date: Available online 4 October 2018Source: Physics and Chemistry of the Earth, Parts A/B/CAuthor(s): Bruno Martins, Ana C. Meira Castro, Carmen Ferreira, Luciano Lourenço, Adélia NunesAbstractIt is known that the erosion process triggered by gullies contributes to significant soil loss and land degradation, and this can limit the options for the occupation and development of a territory in terms of the suitability and quality of the farmland area. The variety of physical factors associated with gully formation hinders straightforward interpretations and requires well-grounded analysis based on l...
Source: Physics and Chemistry of the Earth, Parts ABC - October 6, 2018 Category: Science Source Type: research

Drought dynamics and interannual rainfall variability on the Ghaap plateau, South Africa, 1918–2014
This study was based on long-term rainfall data for three meteorological stations (Postmasburg, Douglas and Groblershoop) from 1918 to 2014, sourced from the South African Weather Services (SAWS). Calculation of the Standardized Precipitation Index (SPI) showed that more droughts occurred since the 1990s; these droughts were all moderately dry with SPI values ranging between −1.03 and −1.46, except for the 1992 drought at Groblershoop which was severe. The longest drought duration on record in the study area was 2 years. Fitting of the long-term rainfall data to a non-parametric spline smoother revealed that th...
Source: Physics and Chemistry of the Earth, Parts ABC - October 5, 2018 Category: Science Source Type: research

Arsenic, iron and chloride in drinking water at primary school, Satkhira, Bangladesh
In this study, potable water supplies for primary school children were examined at Satkhira district, Bangladesh to ensure arsenic-free drinking water. In 240 randomly selected tube wells water of the primary schools were monitored from the seven Upazilas in Satkhira district, Bangladesh. The metal content, especially arsenic and iron in the tube wells water were analyzed by atomic absorption spectroscopy. Results indicate that arsenic content was exceeded the World Health Organization (WHO) guideline value maximum contaminated level (10 μg/L) in 49% of the tube wells water and reached up to 167.9 μg/L. The level...
Source: Physics and Chemistry of the Earth, Parts ABC - October 5, 2018 Category: Science Source Type: research

An assessment of land cover changes in a protected nature reserve and possible implications on water resources, South Africa.
In this study, we characterise land cover and land use changes in Kwelera Nature Reserve, located along the coastal regions of the Eastern Cape in order to determine possible impacts on water resources in the area. To achieve this objective, moderate resolution satellite data (30-m Landsat series imagery) acquired in the year 1995 and 2016 were used. Image classification was done using maximum likelihood classification algorithm. The results show that significant Land Cover/Use changes have occurred at Kwelera Nature Reserve. For example, in the year 1995, it was observed that bare surfaces had an area coverage of 92.47ha ...
Source: Physics and Chemistry of the Earth, Parts ABC - October 5, 2018 Category: Science Source Type: research