Temporal correlation patterns in pre-seismic electromagnetic emissions reveal distinct complexity profiles prior to major earthquakes
Publication date: Available online 7 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Reik V. Donner , Stelios M. Potirakis , Georgios Balasis , Konstantinos Eftaxias , Jürgen Kurths In the last years, continuous recordings of electromagnetic emissions from geophysical observatories have been recognized to exhibit characteristic fluctuation patterns prior to some major earthquakes. To further evaluate and quantify these findings, this work presents a detailed assessment of the time-varying correlation properties of such emissions during the preparatory phases preceding some recent earthqu...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

An Input-Output table based analysis on the virtual water by sectors with the five northwest provinces in China
Publication date: Available online 10 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Chenchen Shi , Jinyan Zhan Virtual water refers to the volumes of water required to produce a commodity or service. It reflects human’s actual consumption of water resources and therefore has certain significance in water resources management. Over the years, the concept of virtual water has caught the attentions of water manager and decision maker. In order to utilize this concept, the accounting and estimation of virtual water is the foundation that lies in this issue. Till now, the accounting method...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

Impact analysis of government investment on water projects in the arid Gansu Province of China
Publication date: Available online 13 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Zhan Wang , Xiangzheng Deng , Xiubin Li , Qing Zhou , Haiming Yan In this paper, we introduced three-nested Constant Elasticity of Substitution (CES) production function into a static Computable General Equilibrium (CGE) Model. Through four levels of factor productivity, we constructed three nested production function of land use productivity in the conceptual modeling frameworks. The first level of factor productivity is generated by the basic value-added land. On the second level, factor productivity in ea...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

Laboratory measurements on radon exposure effects on local environmental temperature: Implications for satellite TIR measurements
Publication date: Available online 15 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Giovanni Martinelli , Andrzej Tomasz Solecki , Dagmara Eulalia Tchorz-Trzeciakiewicz , Magdalena Piekarz , Katarzyna Karolina Grudzinska Surface latent heat flux (SLHF) is proportional to the heat released by phase changes during solidification, evaporation or melting. Effects of SLHF on the earth’s surface could be measured by satellite techniques capable of measuring thermal infrared radiation (TIR). Recent studies have found a possible correlation between SLHF and earthquakes, hence satellite techni...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

TEC variations over the Mediterranean before and during the strong earthquake (M=6.5) of 12th October 2013 in Crete, Greece
Publication date: Available online 16 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): M.E. Contadakis , D.N. Arabelos , G. Vergos , S.D. Spatalas , M. Skordilis In this paper, the total electron content (TEC) data from eight global positioning system (GPS) stations of the EUREF network, provided by IONOLAB (Turkey), were analyzed using discrete Fourier analysis to investigate the TEC variations over the Mediterranean before and during the strong earthquake of 12th October 2013, which occurred west of Crete, Greece. In accordance with the results of similar analyses in the area, the main concl...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

Patterns of Significant Seismic Quiescence on the Mexican Pacific Coast
Publication date: Available online 18 April 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): A. Muñoz-Diosdado , A.H. Rudolf-Navarro , F. Angulo-Brown , A.G. Barrera-Ferrer Many authors have proposed that the study of seismicity rates is an appropriate technique for evaluating how close a seismic gap may be to rupture. We designed an algorithm for identification patterns of significant seismic quiescence by using the definition of seismic quiescence proposed by Schreider (1990). This algorithm shows the area of quiescence where an earthquake of great magnitude may probably occur. We have appl...
Source: Physics and Chemistry of the Earth, Parts ABC - May 1, 2015 Category: Science Source Type: research

A new approach to assessing the water footprint of hydroelectric power based on allocation of water footprints among reservoir ecosystem services
In this study, we developed a new approach to quantify the water footprint of hydroelectric power (WF h) by separating it from the reservoir water footprint (WF) using an allocation coefficient (ηh) based on the ratio of the benefits from hydroelectric power to the total ecosystem service benefits. We used this approach in a case study of the Three Gorges Reservoir, the world’s largest reservoir, which provides multiple ecosystem services. We found large differences between the WF h and the water footprint of per unit of hydroelectric production (PWF h) calculated using ηh and those calculated without this fa...
Source: Physics and Chemistry of the Earth, Parts ABC - April 1, 2015 Category: Science Source Type: research

Identification of the meta-instability stage via synergy of fault displacement: an experimental study based on the digital image correlation method
Publication date: Available online 21 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Yan-Qun Zhuo , Jin Ma , Yan-Shuang Guo , Yun-Tao Ji In stick-slip experiments modeling the occurrence of earthquakes, the meta-instability stage (MIS) is the process that occurs between the peak differential stress and the onset of sudden stress drop. The MIS is the final stage before a fault becomes unstable. Thus, identification of the MIS can help to assess the proximity of the fault to the earthquake critical time. A series of stick-slip experiments on a simulated strike-slip fault were conducted using a...
Source: Physics and Chemistry of the Earth, Parts ABC - March 22, 2015 Category: Science Source Type: research

GIS-based emergency response system for sudden water pollution accidents
Publication date: Available online 21 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Yikang Rui , Dingtao Shen , Shoaib Khalid , Zaigui Yang , Jiechen Wang The frequent occurrence of sudden water pollution accidents brings enormous risks to water environment safety. Therefore, there is great need for the modelling and development of early warning systems and rapid response procedures for current water pollution situation in China. This paper proposes an emergency response system based on the integration of Geographic Information System (GIS) technology and a hydraulic / water-quality model. ...
Source: Physics and Chemistry of the Earth, Parts ABC - March 22, 2015 Category: Science Source Type: research

Changes in Animal Activity Prior to a Major (M=7) Earthquake in the Peruvian Andes
Publication date: Available online 17 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Rachel A. Grant , Jean Pierre Raulin , Friedemann T. Freund During earthquake preparation geophysical processes occur over varying temporal and spatial scales, some leaving their mark on the surface environment, on various biota, and even affecting the ionosphere. Reports on pre-seismic changes in animal behaviour have been greeted with scepticism by the scientific community due to the necessarily anecdotal nature of much of the evidence and a lack of consensus over possible causal mechanisms. Here we presen...
Source: Physics and Chemistry of the Earth, Parts ABC - March 17, 2015 Category: Science Source Type: research

Precursory signatures in the visibility graph analysis of seismicity: an application to the Kachchh (Western India) seismicity
Publication date: Available online 14 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Luciano Telesca , Michele lovallo , S.K. Aggarwal , P.K. Khan The Visibility Graph (VG) method maps time series into networks or graphs, converting dynamical properties of time series in topological properties of networks. The VG method was applied to the aftershock depleted catalogue of the Kachchh Gujarat (Western India) seismicity from 2003 to 2012, in order to identify possible precursory signatures in the pattern of the VG parameters. The k-M slope (the slope of the line fitting the relationship between...
Source: Physics and Chemistry of the Earth, Parts ABC - March 16, 2015 Category: Science Source Type: research

A Temperature-Dependent Multi-Relaxation Spectroscopic Dielectric Model for Thawed and Frozen Organic Soil at 0.05-15 GHz
Publication date: Available online 14 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Valery Mironov , Igor Savin A dielectric model for thawed and frozen Arctic organic-rich soil (50% organic matter) has been developed. The model is based on soil dielectric measurements that were collected over ranges of gravimetric moisture from 0.03 to 0.55 g/g, dry soil density from 0.72 to 0.87 g/cm3, and temperature from 25 to -30°C (cooling run) in the frequency range of 0.05-15 GHz. The refractive mixing dielectric model was applied with the Debye multi-relaxation equations to fit the measurements...
Source: Physics and Chemistry of the Earth, Parts ABC - March 16, 2015 Category: Science Source Type: research

A Model of the generation of electromagnetic emissions detected prior to earthquakes
Publication date: Available online 16 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): M.K. Kachakhidze , N.K. Kachakhidze , T.D. Kaladze AbstractRecent satellite and ground-based observations prove that during the formative period of earthquakes VLF/LF and ULF electromagnetic emissions are observed in seismogenic areas. This work offers an original model of self-generated electromagnetic oscillations of local segments of the lithospheric origins of the emissions. In the paper, the seismogenic area is considered to be an oscillatory- distributed system. This model simplifies physical analyses ...
Source: Physics and Chemistry of the Earth, Parts ABC - March 16, 2015 Category: Science Source Type: research

Surface Soil Moisture Retrievals from Remote Sensing: Current Status, Products & Future Trends
Publication date: Available online 14 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): George P. Petropoulos , Gareth Ireland , Brian Barrett Advances in Earth Observation (EO) technology, particularly over the last two decades, have shown that soil moisture content (SMC) can be measured to some degree or other by all regions of the electromagnetic spectrum, and a variety of techniques have been proposed to facilitate this purpose. In this review we provide a synthesis of the efforts made during the last 20 years or so towards the estimation of surface SMC exploiting EO imagery, with a particu...
Source: Physics and Chemistry of the Earth, Parts ABC - March 14, 2015 Category: Science Source Type: research

Anomalous CO2 content in the Gallicano thermo-mineral spring (Serchio Valley, Italy) before the 21 June 2013, Alpi Apuane Earthquake (M = 5.2)
Publication date: Available online 14 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): L. Pierotti , F. Botti , V. D’Intinosante , G. Facca , F. Gherardi Since late 2002, a continuous automatic monitoring network is operating in Tuscany, Central Italy, to investigate the geochemical response of selected aquifers to local seismic activity. The monitoring is aimed at identifying possible earthquake geochemical precursors. The network is currently constituted by six stations, all equipped with sensors for the measurement of temperature, pH, redox potential, electrical conductivity, CO2 and ...
Source: Physics and Chemistry of the Earth, Parts ABC - March 14, 2015 Category: Science Source Type: research

Application of hydrogeochemical modelling in simulating the transportation of elements in fly ash heap under different disposal systems in South Africa
Publication date: Available online 4 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): J.M. Mbugua , J.C. Ngila , A. Kindness , M. Demlie Ash heap modelling of South African fly ash from Tutuka was carried out and the duration of transportation projected for 20years based on two disposal scenarios, namely; irrigation of ash with rainwater, and irrigation with brines. The hydrogeochemical modeling code, PHREEQC, was applied in the study which gave insights into the speciation, release and transport of elements from the water and brines–fly ash long term interactions. Tutuka ash–wa...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Integrating TRMM and MODIS satellite with socio-economic vulnerability for monitoring drought risk over a tropical region of India
Publication date: Available online 19 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Aradhana Yaduvanshi , Prashant K. Srivastava , A.C. Pandey Drought is a recurring feature of the climate, responsible for social and economic losses in India. In the present work, attempts were made to estimate the drought hazard and risk using spatial and temporal datasets of Tropical Rainfall Measuring Mission (TRMM) and Moderate Resolution Imaging Spectroradiometer (MODIS) in integration with socio-economic vulnerability. The TRMM rainfall was taken into account for trend analysis and Standardized Prec...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

On diurnal dependence and spatial scales of seismo-ionospheric effects in the E-layer
Publication date: Available online 19 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): E.V. Liperovskaya , C.-V. Meister , D.H.H. Hoffmann , A.S. Silina In the present work, disturbances of the f b E s -frequency of the sporadic E-layer of the ionosphere are investigated in connection with earthquakes. The f b E s -frequency is proportional to the square root of the maximum ionisation density of the sporadic E-layer. In this work, it is shown that two days before a seismic shock with magnitude M > 5.5 , and during the shock, an increase of the f b E s -frequency...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Seismo-meteo-electromagnetic phenomena observed during a 5-year interval around the 2011 Tohoku earthquake
Publication date: Available online 19 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Alexander Schekotov , Masashi Hayakawa The purpose of the paper is to try to find ULF electromagnetic precursors to the 2011 Tohoku earthquake (EQ), on the basis of extensive investigation of radiations in vertical component of the magnetic field or with a large ratio of the vertical to full horizontal component. Nighttime records have been analyzed of three Japanese fluxgate magnetometers located in a distance from 300 to 1300km from the epicenter of the main shock, and the frequency range from 10 to 150...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

VLF/LF signal studies of the ionospheric response to strong seismic activity in the Far Eastern region combining the DEMETER and ground-based observations
Publication date: Available online 21 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): A. Rozhnoi , M. Solovieva , M. Parrot , M. Hayakawa , P.-F. Biagi , K. Schwingenschuh , V. Fedun The paper presents the results of a joint analysis of ground-based and satellite observations of very low-frequency and low-frequency (VLF/LF) signals during periods of strong seismic activity in the region of Kuril Islands and Japan in 2004–2010. Ground and satellite data was processed using a method based on the difference between the real signal in nighttime and that of a model. The results of the ana...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Time-Frequency analysis of VLF for seismic-ionospheric precursor detection: Evaluation of Zhao-Atlas-Marks and Hilbert-Huang Transforms
Publication date: Available online 21 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): C. Skeberis , Z.D. Zaharis , T.D. Xenos , S. Spatalas , D.N. Arabelos , M.E. Contadakis This work investigates the application of two post-processing methods of extracting spectra from VLF signals in order to detect disturbances that could be attributed to seismic-ionospheric precursory phenomena. Although precursory phenomena have been investigated in detail in past studies, a different application of time-frequency analysis methods may produce distinct patterns, which reveal disturbances in the VLF spec...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Simulated water productivity in Gansu Province, China
In this study, we define “water productivity” as the changes of economic production outputs of sectoral activities in every cubic meter of water input, which is also the technical coefficient of water resource use in each sector. According to Computable General Equilibrium (CGE) framework, based on the Input–Output Table 2007 and water resources bulletin of Gansu Province, we introduced the water into the ORANI-G (A Generic Single-Country Computable General Equilibrium model) model through the nested constant elasticity of substitution (CES) production function to analyze the changes of economic productio...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Impact of land-use induced changes on agricultural productivity in the Huang-Huai-Hai River Basin
Publication date: Available online 24 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Gui Jin , Zhaohua Li , Zhan Wang , Xi Chu , Zhihui Li The water resource allocation is greatly influenced by the land use, agricultural productivity and farmers’ income. Therefore analyzing the impacts of land use changes on agricultural productivity and subsequent effects on farmer’s income is an important basis of the further study on the management mechanism and optimal water resource allocation. Taking the Huang-Huai-Hai River Basin as the study area, this study examined the impacts of con...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Inferring land surface parameters from the diurnal variability of microwave and infrared temperatures
This study investigates the properties of the diurnal cycle of microwave brightness temperatures (TB), namely the phase and the amplitude, and their variability in time and space over the globe to infer information on key land surface parameters like changes in soil texture spatial distribution, soil moisture conditions, and vegetation density. The phase corresponds to the lag between Land Surface Temperature (LST) and TB diurnal cycles. The amplitude is determined as the difference between the maximum and the minimum of TB diurnal cycle. The diurnal cycle of TB was constructed using observations from the Advanced Microwav...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Evidence for tidal triggering on the earthquakes of the Hellenic Arc, Greece
Publication date: Available online 28 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): G. Vergos , D.N. Arabelos , M.E. Contadakis In this paper we investigate the tidal triggering evidence on the earthquakes of the seismic area of the Hellenic Arc using the Hist(ogram)Cum(mulation) method. We analyze the series of the earthquakes occurred in the area which is confined by the longitudes 22° and 28°E and latitudes 34° and 36°N in the time period from 1964 to 2012. In this time period 16,137 shallow and of intermediate depth earthquakes with ML up to 6.0 and 1,482 deep earthqu...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

A qualitative study of seismic-ionospheric precursor phenomena monitored by a very close to the epicenter VLF and LF receiver
Publication date: Available online 5 March 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): C. Skeberis , Z.D. Zaharis , T.D. Xenos , S. Spatalas , M.E. Contadakis This work investigates the occurrence of disturbances across a wide range of VLF and LF frequencies received prior to a seismic event (Mw=4), that took place on May 12th 2012, the epicenter of which was very close (14Km) to the VLF/LF station. The signals analysed were emitted from five VLF and five LF European transmitters. This seismic event produced precursory ionospheric disturbances, identified as spectral distortion, three days befo...
Source: Physics and Chemistry of the Earth, Parts ABC - March 10, 2015 Category: Science Source Type: research

Multilevel modeling of NPP change and impacts of water resources in the Lower Heihe River Basin
This study analyzed the impacts of potential influencing factors on NPP in the lower Heihe River Basin, a typical arid and semi-arid region in China. First, NPP was estimated with the C-FIX model, and then the multilevel model was used to analyze the impacts of potential influencing factors on NPP during 2000–2008. Finally decomposition analysis was used to further analyze the contribution of influencing factors to NPP change during 2000–2008. The average NPP increased by approximately 9.07% during 2000–2008, and results of the multilevel model indicate that both the socioeconomic variables and demographi...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Predicting streamflow for land cover changes in the Upper Gilgel Abay River Basin, Ethiopia: A TOPMODEL based approach
Publication date: Available online 10 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): W. Gumindoga , T.H.M. Rientjes , A.T. Haile , T. Dube Hydrological effects of land cover changes and runoff contributions from respective land cover types are analysed for the Upper Gilgel Abay basin in Ethiopia. Runoff production and streamflow are simulated by the TOPMODEL approach. For impact assessment of land cover changes, satellite based land covers for the years 1973, 1986 and 2001 are considered. Catchment topography as well as land cover and vegetation characteristics are derived from satellite i...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Evaluation of sample preparation methods for the detection of total metal content using inductively coupled plasma optical emission spectrometry (ICP-OES) in wastewater and sludge
Publication date: Available online 10 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): K.M. Dimpe , J.C. Ngila , N. Mabuba , P.N. Nomngongo Heavy metal contamination exists in aqueous wastes and sludge of many industrial discharges and domestic wastewater, among other sources. Determination of metals in the wastewater and sludge requires sample pre-treatment prior to analysis because of certain challenges such as the complexity of the physical state of the sample, which may lead to wrong readings in the measurement. This is particularly the case with low analyte concentration to be detected ...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Predictive complexation models of the impact of natural organic matter and cations on scaling in cooling water pipes: a case study of power generation plants in South Africa
The objective of modelling was to describe scaling in terms of saturation indices of mineral phases. Accordingly, the minerals most likely to generate scale were further simulated (over a range of pH (3-10) to yield results that mimicked changing pH. Speciation calculations of Cu2+, Pb2+ and Zn2+ generated azurite, cerrusite and smithsonite mineral phases, which showed positive saturation indices at higher pH, hence increased potential to precipitate (form scale). The derived predictive models would act as a useful management tool and henceforth aid to avoid unnecessary costs due to the consequences of scaling. (Source: Ph...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

An analysis of the effectiveness of WASH interventions in relation to diarrhoeal diseases in Chipinge district, Zimbabwe
The objectives of the study were to determine the existing WASH interventions in the ward, to assess the KAP on WASH interventions as a mitigation measure against diarrhoeal disease, to analyse the trend of diarrhoea from 2005 to 2011 and to analyse the behaviour change attributed to WASH interventions. Data was collected using interviews, questionnaires, FGDs and observation checklists. Data was analysed using SPSS version 16.0 and qualitative data was analysed by developing themes related to specific objectives. Results showed that WASH interventions were in place in all the villages of ward 22 though they were inadequat...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Pathways for building capacity and ensuring effective transboundary water resources management in Africa: Revisiting the key issues, opportunities and challenges
Publication date: Available online 12 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Claudious Chikozho The performance of most organizations and institutions set up to facilitate transboundary water resources management in Africa remains unsatisfactory and new frameworks are required to address this performance gap. Using the Nile and Senegal River Basins as case studies, this paper applies qualitative research methods to explore the transboundary river basin management terrain in Africa with a view to identifying and articulating some of the major issues, challenges and opportunities fac...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Fractionation of wastewater characteristics for modelling of Firle Sewage Treatment Works, Harare, Zimbabwe
Publication date: Available online 14 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Simon Takawira Muserere , Zvikomborero Hoko , Innocent Nhapi Varying conditions are required for different species of microorganisms for the complex biological processes taking place within the activated sludge treatment system. It is against the requirement to manage this complex dynamic system that computer simulators were developed to aid in optimising activated sludge treatment processes. These computer simulators require calibration with quality data input that include wastewater fractionation among o...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

River health assessment using macroinvertebrates and water quality parameters: a case of the orange river in namibia
This study was aimed at assessing the current water quality and overall health status of the Orange River in Namibia. The South African Scoring System 5(SASS5) was applied in eight sites where samples for macroinvertebrates, physical and chemical water quality parameters such as nutrients in the water, pH, turbidity, presence of bacteria, etc were obtained. Satellite images i.e. Landsat images were also used to assess the land-uses over time in the study area with the view of linking such changes to variance in water quality over time. The SASS5 results indicated a fair water quality and river health condition in category ...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Analysis of institutional mechanisms that support community response to impacts of floods in the middle-zambezi river basin, Zimbabwe
This study analysed institutional mechanisms in Mbire District of Zimbabwe which aim at mitigating the impact of floods. The study used both quantitative (i.e. questionnaires) and qualitative (i.e. key informant interviews, focus group discussions and observations) data collection methods. Secondary data such as policy and legislation documents and operational manuals of organizations that support communities affected by disasters were reviewed. Qualitative data was analysed using the thematic approach and social network analysis using UCINET 6. Quantitative data were analysed using SPSS 19.0. The study found that there ex...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Impacts of small built infrastructure in inland valleys in Burkina Faso and Mali: Rationale for a systems approach that thinks beyond rice?
Publication date: Available online 21 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Pamela Katic , Jonathan Lautze , Regassa E. Namara The potential to increase agricultural production in inland valleys in West Africa has received a good degree of attention in both national development strategies and academic literature, and improving agriculture productivity in inland valleys has been an active area of donor engagement. Despite this attention, documentation of the degree to which benefits are enhanced through construction of built water storage infrastructure in such sites is somewhat sc...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Impacts of land use and land cover changes on surface energy and water balance in the Heihe River Basin of China, 2000–2010
This study aims to analyze the impacts of land use and land cover changes on the energy and water balance in the Heihe River Basin of China during 2000–2010, and four key study sites with representative hydrological stations and dramatic LUCC in the past decades were selected to illustrate the responses of the energy and water balance to LUCC. First, LUCC of the Heihe River Basin from 2000 to 2010 was analyzed based on the interpretation of remote sensing images. Then a series of indicators of the energy and water balances were simulated with the Weather Research and Forecasting (WRF) model and corresponding land use...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Rejection of pharmaceuticals by nanofiltration (NF) membranes: Effect of fouling on rejection behaviour
Publication date: Available online 28 January 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): T.O. Mahlangu , T.A.M. Msagati , E.M.V. Hoek , A.R.D. Verliefde , B.B. Mamba The aim of this study was to investigate the effects of membrane fouling by sodium alginate, latex and a combination of alginate + latex on the rejection behaviour of salts and organics. Sodium chloride and caffeine were selected to represent salts and organics, respectively. The effects of the presence of calcium chloride on the fouling behaviour and rejection of solutes were investigated. The results revealed that the salt rejec...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Application of hydrogeochemical modeling in simulating the transportation of elements in fly ash heap under different disposal systems in South Africa
Publication date: Available online 4 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): J.M. Mbugua , J.C. Ngila , A. Kindness , M. Demlie Ash heap modeling of South African fly ash from Tutuka was carried out and the duration of transportation projected for 20 years based on two disposal scenarios, namely; irrigation of ash with rainwater, and irrigation with brines. The hydrogeochemical modeling code, PHREEQC, was applied in the study which gave insights into the speciation, release and transport of elements from the water and brines-fly ash long term interactions. Tutuka ash-water heap mod...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

An Empirical Study on the Spatial Distribution of the Population, Economy and Water Resources in Northeast China
Publication date: Available online 7 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Conglin Zhang , Yu Liu , Haijuan Qiao The relationship among the population, economy and water resources is complex, and the contradictions and conflicts will appear and aggravate with the rapid development of economy and society in Northeast China. Based on the statistical analysis of the available data, this paper depicted the static distribution characteristics of the population, economy and water resources of Northeast China in 2011. It was found that the spatial distribution of the population, economy...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Hand dug wells in Namibia: An underestimated water source or a threat to human health?
Publication date: Available online 7 February 2015 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): H. W.e , A. Nakwafila , J.T. Hamutoko , C. Lohe , F. Neumbo , I. Petrus , A. David , H. Beukes , N. Masule , M. Quinger The rural population of parts of northern and western Namibia uses hand dug wells for their domestic water supply, partly because no other source (e.g., deep tube wells) is available, but also as a substitute for pipeline water that is often perceived as being too expensive. The water quality of these wells is usually not monitored or controlled, thus a study has been carried out in four ...
Source: Physics and Chemistry of the Earth, Parts ABC - February 17, 2015 Category: Science Source Type: research

Impacts of climate change on water resources in southern Africa: A review
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): Samuel Kusangaya , Michele L. Warburton , Emma Archer van Garderen , Graham P.W. Jewitt The Intergovernmental Panel on Climate Change concluded that there is consensus that the increase of atmospheric greenhouse gases will result in climate change which will cause the sea level to rise, increased frequency of extreme climatic events including intense storms, heavy rainfall events and droughts. This will increase the frequency of climate-related hazards, causing loss of life, social disruption and economic hardshi...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Calibration, validation, parameter indentifiability and uncertainty analysis of a 2 – parameter parsimonious monthly rainfall-runoff model in two catchments in Zimbabwe
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): D.T. Rwasoka , C.E. Madamombe , W. Gumindoga , A.T. Kabobah Hydrologic modelling lies at the core of hydrology and water resources management. Attempts at gaining a holistic grasp on model robustness, hydrologic theory and processes have inadvertently led to models that are not-well structured or too complex to apply in arid and semi-arid catchments and in Africa, in particular. In view of this, this paper reports on the application of a monthly parsimonious hydrologic model in two catchments in Zimbabwe, the Nya...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Impact of spatial input data resolution on hydrological and erosion modeling: Recommendations from a global assessment
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): V. Chaplot The need to precisely describe the characteristics of a landscape is well-known in mathematical modeling from different environmental disciplines. Because spatial input data, such as climate, relief and soil maps are costly to obtain, especially when large areas are considered, several research studies have investigated the extent to which the resolution of these can be reduced. Yet, a consensus has not been reached on the question of models’ sensitivity to the whole range of spatial input data a...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Connectivity influences on nutrient and sediment migration in the Wartburg catchment, KwaZulu-Natal Province, South Africa
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): Kipkemboi J. Kollongei , Simon A. Lorentz Non-point-source (NPS) pollution of surface and groundwater by sediment and nutrient loads emanating from agricultural catchments is a prominent environmental issue, with major consequences on water supply and aquatic ecosystem quality. The concept of connectivity has proved invaluable in understanding migration of NPS pollutants in catchments. Observations of sediments or suspended solids (SS), nitrate (NO3) and phosphorous (P) fluxes alongside stable water isotope sampl...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Estimation of design floods in ungauged catchments using a regional index flood method. A case study of Lake Victoria Basin in Kenya
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): Joel Nobert , Margaret Mugo , Hussein Gadain Reliable estimation of flood magnitudes corresponding to required return periods, vital for structural design purposes, is impacted by lack of hydrological data in the study area of Lake Victoria Basin in Kenya. Use of regional information, derived from data at gauged sites and regionalized for use at any location within a homogenous region, would improve the reliability of the design flood estimation. Therefore, the regional index flood method has been applied. Based ...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Implementing water science research to benefit all
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 67–69 Author(s): Hodson Makurira , Benjamin Mapani , Dominic Mazvimavi , Marloes Mul , Barbara Tapela , Victor Wepener (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

Conceptual model analysis of interaction at a concrete–Boom Clay interface
The objectives of this paper are twofold. First, we develop an efficient coupled reactive transport code for this diffusion-dominated system by making full use of multi-processors/cores computers. Second, we investigate how sensitive the system is to chemical reaction models especially when pore clogging due to mineral precipitation is considered within the cementitious system. To do this, we selected two portlandite dissolution models, i.e., equilibrium (fastest) and diffusion-controlled model with precipitation of a calcite layer around portlandite particles (diffusion-controlled dissolution). The results show that with ...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

OpenGeoSys-Gem: A numerical tool for calculating geochemical and porosity changes in saturated and partially saturated media
We present a new coupling of the Richards flow module of the Finite Element (FE) based OpenGeoSys code with the GEM based chemical solver GEMS3K. The coupled code is highly parallelized using an overlapping domain decomposition approach in combination with execution of multiple threads that solve chemical equilibria in parallel. FE reactive transport schemes are often affected by spurious concentration oscillations. We effectively suppress these oscillations with a linearized algebraic flux corrected transport (FCT) algorithm. An application example is presented which investigates the evolution of material interfaces in a ...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research

A versatile pore-scale multicomponent reactive transport approach based on lattice Boltzmann method: Application to portlandite dissolution
Publication date: 2014 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volumes 70–71 Author(s): Ravi A. Patel , Janez Perko , Diederik Jacques , Geert De Schutter , Klaas Van Breugel , Guang Ye A versatile lattice Boltzmann (LB) based pore-scale multicomponent reactive transport approach is presented in this paper. This approach is intended to capture mineral phase and pore structure evolution resulting from geochemical interactions applicable, for example to model microstructural evolution of hardened cement paste during chemical degradation. In the proposed approach heterogeneous reactions are conceptuali...
Source: Physics and Chemistry of the Earth, Parts ABC - January 5, 2015 Category: Science Source Type: research