A Spatially weighted optimization model (SWOM) for Salinity mapping in Florida Bay using Landsat images and in-situ observations
Publication date: Available online 8 June 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Fahad Khan Khadim, Hongbo Su, Lina Xu (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - June 9, 2017 Category: Science Source Type: research

Non-flood season neap tides in the Yangtze estuary offshore: flow mixing processes and its potential impacts on adjacent wetlands
Publication date: Available online 6 June 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Taoyuan Wei, Zhanghua Wang, Jing Chen, Maotian Li How flow mixing process influences the wetlands of the Yangtze Estuary is still poorly understood. Hydrological fieldwork was conducted on five vessel-anchored sites (S1-S2; M1-M2-M3) near the major wetlands of the Yangtze Estuary offshore (121°57′-122°30′E, 30°50′-31°23′N) on May 8-11 2004, to examine the dynamics of neap tides in the non-flood season of the Yangtze (∼24, 700 m3s-1 at Datong) and their impacts on adja...
Source: Physics and Chemistry of the Earth, Parts ABC - June 7, 2017 Category: Science Source Type: research

Responses of the water-yield ecosystem service to climate and land use change in Sancha River Basin, China
This study shows that the grain-for-green program has negatively impacted water yield. Furthermore, to improve the ecological environment of the river basin, a comprehensive scheme for controlling water and soil erosion should be implemented according to the actual variation in water yield. This would give full consideration to the utility of water resources. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - June 5, 2017 Category: Science Source Type: research

Phosphorus fraction and phosphate sorption-release characteristics of the wetland sediments in the Yellow River Delta
Publication date: Available online 5 June 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Yuan Cui, Rong Xiao, Ying Xie, Mingxiang Zhang The aim of this study was to investigate phosphorus (P) fractions and phosphate sorption-release characteristics of the surface sediments regarding the wetland restoration in the Yellow River Delta (YRD). Sediments samples were collected from three typical sample plots: Phragmites australis community (p), Suaeda salsa community (s), and bare land (b) both in natural wetland (N) and restored wetland (R). The results showed that the mean content of TP was 541.58 mg/k...
Source: Physics and Chemistry of the Earth, Parts ABC - June 5, 2017 Category: Science Source Type: research

Impacts of water scarcity on socio-economic development: A case study of Gaotai County, China
Publication date: Available online 3 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Qing Zhou, Xiangzheng Deng, Feng Wu Provisioning services for socio-economic development are important hydrological ecosystem services that humans obtain from freshwater. The conflict between water scarcity and economic development in arid regions affects water utilization among different sectors. A water resource embedded social accounting matrix (SAM) can help to analyze the relationship between water resource utilization and socio-economic development. In this paper, a water resource embedded SAM was constr...
Source: Physics and Chemistry of the Earth, Parts ABC - May 26, 2017 Category: Science Source Type: research

Set pair analysis method for coordination evaluation in water resources utilizing conflict
Publication date: Available online 12 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Zhengwei Pan, Yanhua Wang, Juliang Jin, Xiaowei Liu In order to describe management problems of water resource system conflicts quantitatively, six elements were proposed in the management of water resources conflicts, which are coordination participator, coordination goal, coordination index, behavioral strategies, coordination situation and coordination rule. In the coordination management of conflicts in water resource systems a coordination index has a lower limiting value meeting the coordination participa...
Source: Physics and Chemistry of the Earth, Parts ABC - May 24, 2017 Category: Science Source Type: research

Reactive transport modelling of cement-groundwater-rock interaction at the Grimsel Test Site
Publication date: Available online 13 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): M. Carme Chaparro, Maarten W. Saaltink, Josep M. Soler An in situ experiment at the Grimsel Test Site (Switzerland) to study water-cement-rock interaction in fractured granite was modelled. It consisted of a hardened cement source in a borehole intersecting a water conducting fracture. Grimsel groundwater was injected into this borehole. Two other boreholes at about 0.56 m and 1.12 m from the emplacement borehole were used to monitor the evolution of water composition for 5 years. The modelling approa...
Source: Physics and Chemistry of the Earth, Parts ABC - May 14, 2017 Category: Science Source Type: research

Set pair analysis method for coordination assessment in water resources utilizing conflict
Publication date: Available online 12 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Zhengwei Pan, Yanhua Wang, Juliang Jin, Xiaowei Liu In order to describe management problems of water resource system conflicts quantitatively, six elements were proposed in the management of water resources conflicts, which are coordination participator, coordination goal, coordination index, behavioral strategies, coordination situation and coordination rule. In the coordination management of conflicts in water resource systems a coordination index has a lower limiting value meeting the coordination participa...
Source: Physics and Chemistry of the Earth, Parts ABC - May 13, 2017 Category: Science Source Type: research

The urbanization efficiency in Chengdu City: An estimation based on a three-stage DEA model
Publication date: Available online 12 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Siqi Jia, Chengxin Wang, Yifan Li, Fan Zhang, Wei Liu With economic development and population growth occurring throughout China, there has been increasing conflicts between resources, environmental protection and economic development in many regions, especially in the developed regions. Therefore, it is important to correctly evaluate the pressure of human activities on the natural environment and the ecosystem carrying capacity at a regional scale. This paper evaluated the urbanization efficiency based on the...
Source: Physics and Chemistry of the Earth, Parts ABC - May 13, 2017 Category: Science Source Type: research

A sorption model for alkalis in cement-based materials – Correlations with solubility and electrokinetic properties
Publication date: Available online 5 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Pierre Henocq In cement-based materials, radionuclide uptake is mainly controlled by calcium silicate hydrates (C-S-H). This work presents an approach for defining a unique set of parameters of a surface complexation model describing the sorption behavior of alkali ions on the C-S-H surface. Alkali sorption processes are modeled using the CD-MUSIC function integrated in the Phreeqc V.3.0.6 geochemical code. Parameterization of the model was performed based on (1) retention, (2) zeta potential, and (3) solubility...
Source: Physics and Chemistry of the Earth, Parts ABC - May 11, 2017 Category: Science Source Type: research

Advance in seismic site response: Usual practices and innovative methods
Publication date: April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volume 98 Author(s): Francesco Panzera, Sebastiano D'Amico, Jan Burjanek, Marta Pischiutta (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - May 9, 2017 Category: Science Source Type: research

Estimating policy pressure for China's cultivated land use protection based on an extended index
Publication date: Available online 5 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Jiandong Chen, Shulei Cheng, Malin Song Based on existing references, using the decomposition technique of the second model of the logarithmic mean Divisia index (LMDI) decomposition method and the principle of “jointly created and equally distributed” of the Refined Laspeyres (RL) index, this paper developed a new policy pressure index and applied it to estimate the policy pressure for China's cultivated land use protection. The results indicated that, first, the policy pressure for China's cultivat...
Source: Physics and Chemistry of the Earth, Parts ABC - May 8, 2017 Category: Science Source Type: research

Transport properties evolution of cement model system under degradation - Incorporation of a pore-scale approach into reactive transport modelling
Publication date: Available online 6 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): N. Seigneur, E. L’Hôpital, A. Dauzères, J. Sammaljavi, M. Voutilainen, P.E. Labeau, A. Dubus, V. Detilleux This paper describes a multi-scale approach for the modelling of the degradation of model cement pastes using reactive transport. It specifically aims at incorporating chemistry-transport feedback results from a pore-scale approach into a continuum description. Starting from a numerical representative elementary volume of the model cement paste, which was built according to extensive expe...
Source: Physics and Chemistry of the Earth, Parts ABC - May 8, 2017 Category: Science Source Type: research

A sorption model for alkalis in cement-based material – Correlations with solubility and electrokinetic properties
Publication date: Available online 5 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Pierre Henocq In cement-based materials, radionuclide uptake is mainly controlled by calcium silicate hydrates (C-S-H). This work presents an approach for defining a unique set of parameters of a surface complexation model describing the sorption behavior of alkali ions on the C-S-H surface. Alkali sorption processes are modeled using the CD-MUSIC function integrated in the Phreeqc V.3.0.6 geochemical code. Parameterization of the model was performed based on (1) retention, (2) zeta potential, and (3) solubility...
Source: Physics and Chemistry of the Earth, Parts ABC - May 6, 2017 Category: Science Source Type: research

Estimating policy pressure for China ’s cultivated land use protection based on an extended index
Publication date: Available online 5 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Jiandong Chen, Shulei Cheng, Malin Song Based on existing references, using the decomposition technique of the second model of the logarithmic mean Divisia index (LMDI) decomposition method and the principle of “jointly created and equally distributed” of the Refined Laspeyres (RL) index, this paper developed a new policy pressure index and applied it to estimate the policy pressure for China’s cultivated land use protection. The results indicated that, first, the policy pressure for China&rsqu...
Source: Physics and Chemistry of the Earth, Parts ABC - May 6, 2017 Category: Science Source Type: research

Ecological security assessment based on ecological footprint approach in Beijing-Tianjin-Hebei region, China
This study finally concludes that whether the whole region or the sub-regions, their existing development patterns were unsustainable, and ecological security situation was serious. (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - May 5, 2017 Category: Science Source Type: research

Adsorption of gluconate and uranyl on C-S-H phases: Combination of wet chemistry experiments and molecular dynamics simulations for the binary systems
Publication date: Available online 4 May 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Iuliia Androniuk, Catherine Landesman, Pierre Henocq, Andrey G. Kalinichev As a first step in developing better molecular scale understanding of the effects of organic additives on the adsorption and mobility of radionuclides in cement under conditions of geological nuclear waste repositories, two complementary approaches, wet chemistry experiments and molecular dynamics (MD) computer simulations, were applied to study the sorption behaviour of two simple model systems: gluconate and uranyl on calcium silicate h...
Source: Physics and Chemistry of the Earth, Parts ABC - May 5, 2017 Category: Science Source Type: research

Modelling of Chemical Degradation of Blended Cement-based Materials by Leaching Cycles with Callovo-Oxfordian Porewater
The objective of this study is to provide an equilibrium solution composition for each degradation state for a CEM-V cement-based material to support the adsorption and diffusion experiments reproducing any state of degradation. Calculations have been performed at 25 ºC using the geochemical code PhreeqC and an up-to-date thermodynamic database (ThermoChimie v.9.0.b) coupled to SIT approach for ionic strength correction. The model replicates experimental data with accuracy. The approach followed in this study eases the analysis of the chemical evolution in both aqueous and solid phase to obtain a fast assessment of th...
Source: Physics and Chemistry of the Earth, Parts ABC - May 5, 2017 Category: Science Source Type: research

Factors influencing sustainability of communally-managed water facilities in rural areas of Zimbabwe
This study was done in Zimbabwe to investigate the factors influencing sustainability of rural water supply systems. A total of 399 water points were studied in Nyanga, Chivi and Gwanda districts. Data was collected using a questionnaire, observation checklist and key informant interview guide. Multi-Criteria analysis was used to assess the sustainability of water points and inferential statistical analysis such as Chi square tests and Analysis of Variance (ANOVA) were used to determine if there were significant differences on selected variables across districts and types of lifting devices used in the study area. The them...
Source: Physics and Chemistry of the Earth, Parts ABC - April 29, 2017 Category: Science Source Type: research

Water Security for Productive Economies: Applying an Assessment Framework in southern Africa
Publication date: Available online 27 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Bunyod Holmatov, Jonathan Lautze, Herath Manthrithilake, Ian Makin Achieving water security has emerged as a major objective in Africa, yet an analytical or diagnostic framework for assessing water security in African countries is not known to exist. This paper applies one key dimension of the 2016 Asian Development Bank’s (ADB) Asian Water Development Outlook (AWDO) to assess levels of water security for productive economies in countries of the Southern African Development Community (SADC). Economic as...
Source: Physics and Chemistry of the Earth, Parts ABC - April 28, 2017 Category: Science Source Type: research

Dispersion of inorganic contaminants in surface water in the vicinity of Potchefstroom
Publication date: Available online 27 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): A. Manyatshe, E. Fosso-Kankeu, D. van der Berg, N. Lemmer, F. Waanders, H. Tutu Potchefstroom and the neighbouring cities rely mostly on the Mooi River and Vaal River for their water needs. These rivers flow through the gold mining areas and farms, and are therefore likely to be contaminated with substantial amounts of inorganic pollutants. Water was collected along the rivers network, streams, canals and dams in Potchefstroom and the vicinity. The samples were characterized for geochemical parameters, metals...
Source: Physics and Chemistry of the Earth, Parts ABC - April 28, 2017 Category: Science Source Type: research

Short-term effects of tidal flooding on soil nitrogen mineralization in a Chinese tidal salt marsh
Publication date: Available online 26 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Haifeng Gao, Junhong Bai, Xiaoya Deng, Qiongqiong Lu, Xiaofei Ye Tidal flooding is an important control of nitrogen biogeochemistry in wetland ecosystems of Yellow River Delta, China. Variations in hydrology could change soil redox dynamics and conditions for microorganisms living. A tidal simulation experiment was designed to extract tidal flooding effect on nitrogen mineralization of salt marsh soil. Inorganic nitrogen and relevant enzyme were measured during the 20-day incubation period. Considering the va...
Source: Physics and Chemistry of the Earth, Parts ABC - April 27, 2017 Category: Science Source Type: research

Determination of Toxic Metals in Drinking Water Sources in the Chief Albert Luthuli Local Municipality in Mpumalanga, South Africa
This study was conducted to determine the presence and levels of toxic metals on selected water sources in a rural community in Lochiel, South Africa. Collection of water samples from identified drinking water sources (open wells, community tanks, water treatment works and boreholes) was done in all seasons of the year (winter, spring, summer and autumn) between 2014 and 2015. The concentrations of identified toxic metals (cobalt, chromium, copper, lead, zinc, manganese and iron) were measured using ICP-OES. Some water sources were found to contain concentrations of toxic metals at levels slightly higher than USEPA, WHO an...
Source: Physics and Chemistry of the Earth, Parts ABC - April 27, 2017 Category: Science Source Type: research

Reactive transport modelling of a high-pH infiltration test in concrete
Publication date: Available online 4 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): M. Carme Chaparro, Josep M. Soler, Maarten W. Saaltink, Urs K. Mäder A laboratory-scale tracer test was carried out to characterize the transport properties of concrete from the Radioactive Waste Disposal Facility at El Cabril (Spain). A hyperalkaline solution (K-Ca-OH, pH = 13.2) was injected into a concrete sample under a high entry pressure in order to perform the experiment within a reasonable time span, obtaining a decrease of permeability by a factor of 1000. The concentrations of the t...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Effects of calcium leaching on diffusion properties of hardened and altered cement pastes
This study focused on the spatial distribution of these cement phases. The auto-correlation function of each phase of cementitious materials was calculated from two-dimensional backscattered electron imaging, and the three-dimensional spatial image of the cementitious material was produced using these auto-correlation functions. An attempt was made to estimate the diffusion coefficient of chloride from the three-dimensional spatial image. The estimated diffusion coefficient of the altered sample from the three-dimensional spatial image was found to be comparable to the measured value. This demonstrated that it is possible ...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Soft X-ray absorption near-edge investigations of Mg-containing mineral phases relevant for cementitious materials
Publication date: Available online 18 March 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): M. Vespa, R. Dähn, T. Huthwelker, E. Wieland (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Impacts of land use/cover change on terrestrial carbon stocks in Uganda
Publication date: Available online 18 March 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Fan Zhang, Jinyan Zhan, Qian Zhang, Lina Yao, Wei Liu Land use/cover change, especially conversion and degradation of forest land, is the key factor causing terrestrial carbon stocks declines in Uganda. How local ecological assemblages are responding is less clear—a concern given their importance for many ecosystem functions and services. The main objectives are to assess status and variation in carbon stocks across land covers and quantify spatial distribution and dynamic variation of terrestrial carbo...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Optimization of land-use management for ecosystem service improvement: A review
Publication date: Available online 23 March 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Gui Jin, Xiangzheng Deng, Xi Chu, Zhihui Li, Yuan Wang Land use is closely related to human activity, which affect ecosystem services by changing the types, patterns and ecological processes of ecosystem, and consequently impact the human well-being. Scientific simulation is needed to analyze the land use policy impacts on ecosystem services and socioeconomic development. Based on the reviews, the Computable General Equilibrium (CGE) model plays an important role in building simulation framework for land-use ...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Impacts of water scarcity on social economic development: A case study of Gaotai County, China
Publication date: Available online 3 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Qing Zhou, Xiangzheng Deng, Feng Wu Provisioning services for socio-economic development is an important hydrological ecosystem services human obtains from freshwater. The dilemma between water scarcity and economic development in arid regions influence water utilization among different sectors. A water resource embedded Social Accounting Matrix (WSAM) helps to analyze the interrelation between water resource utilization and social economic development. In this paper, by establishing the WSAM and applying SAM ...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Effects of soil abiotic factors on the plant morphology in an intertidal salt marsh, Yellow River Delta, China
Publication date: Available online 4 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Shanze Li, Baoshan Cui, Junhong Bai, Tian Xie, Jiaguo Yan, Qing Wang, Shuyan Zhang Plant morphology plays important role in studying biogeography in many ecosystems. Suadea salsa, as a native plant community of northern China and an important habitat for diversity of waterbirds and macrobenthos, has often been overlooked. Nowadays, S. salsa community is facing great loss due to coastal reclamation activities and natural disturbances. To maintain and restore S. salsa community, it's important to addre...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Vertical distribution of mercury and MeHg in Nandagang and Beidagang wetlands: Influence of microtopography
Publication date: Available online 4 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Ruhai Liu, Yanyan Zhang, Yan Wang, Jin Zhao, Huayao Shan Wetlands often show different small-scale topography, such as riffle, habitat island, deep water, shallow water zone and dry zone. Core soils in different micro topographical landforms of Nandagang and Beidagang wetlands in North China were sampled for THg and MeHg to analyze the influence of microtopography. Results showed that THg content in surface soil (<2 cm) was little higher than that at depth 2–4 cm of all stations. There w...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Soil carbon, nitrogen, and phosphorus stoichiometry of three dominant plant communities distributed along a small-scale elevation gradient in the East Dongting Lake
Publication date: Available online 4 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Cong Hu, Feng Li, Yong-hong Xie, Zheng-miao Deng, Xin-sheng Chen Soil carbon (C), nitrogen (N), and phosphorus (P) stoichiometry greatly affects plant community succession and structure. However, few studies have examined the soil stoichiometric changes in different vegetation communities of freshwater wetland ecosystems along an elevation gradient distribution. In the present study, soil nutrient concentrations (C, N, and P), soil stoichiometry (C:N, C:P, and N:P ratios), and other soil physicochemical charac...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Emergy analysis on urban metabolism by counties in Beijing
Publication date: Available online 6 April 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Wei Qi, Xiangzheng Deng, Xi Chu, Chunhong Zhao, Fan Zhang Beijing is an international metropolis, with rapid urbanization during the last 30 years. However, it faces the challenge of sustainability with limited natural resources. This paper attempts to incorporate emergy analysis on urban metabolism to investigate the sustainability of the entire Beijing at the county level. Based on the time-series climate data and socioeconomic data, we calculated the structure, intensities, environment pressures and output ...
Source: Physics and Chemistry of the Earth, Parts ABC - April 11, 2017 Category: Science Source Type: research

Assessment of the content, structure, and source of soil dissolved organic matter in the coastal wetlands of Jiaozhou Bay, China
Publication date: Available online 6 March 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Min Xi, Yuanyuan Zi, Qinggai Wang, Sen Wang, Guolu Cui, Fanlong Kong The contents and structure of dissolved organic matter (DOM) in four typical wetlands, such as naked tidal, suaeda salsa, reed and spartina, were conducted to investigate the content, structure, and source of dissolved organic matter in coastal wetland soil. The soil samples were obtained from Jiaozhou Bay in January, April, July, and October of 2014. Results showed that the DOM contents in soil of four typical wetland were in order of sparti...
Source: Physics and Chemistry of the Earth, Parts ABC - March 6, 2017 Category: Science Source Type: research

The study on ecological sustainable development in Chengdu
In this study, we combine ecological footprint with system dynamics software STELLA to construct a predictable model of ecological sustainable development. We introduce rate1 and rate2 into the model, which reflects the change in per capita consumption of biological resources and energy due to the socio-economic development, and by changing the values of them to simulate a variety of scenarios. The results show that ecological sustainable development of Chengdu is in the state of ecological deficit, which is 1.43 million hm2 in 2013, and different rate1 and rate2 will lead to different changes in the ecological deficit. Wh...
Source: Physics and Chemistry of the Earth, Parts ABC - March 6, 2017 Category: Science Source Type: research

Exploration of the causality between area changes of green spaces and waterlogging frequency in Beijing
Publication date: Available online 7 March 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Guofeng Wang, Jiancheng Chen, Chunhong Zhao, Xiaoxue Zhou, Xiangzheng Deng (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - March 6, 2017 Category: Science Source Type: research

Wetland biogeochemistry and ecological risk assessment
Publication date: February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volume 97 Author(s): Junhong Bai, Laibin Huang, Haifeng Gao, Guangliang Zhang (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - February 28, 2017 Category: Science Source Type: research

Prediction of non-linear site response using downhole array data and numerical modeling: The Belleplaine (Guadeloupe) case study
In this study, we analyze the acceleration time histories data at the Belleplaine (Guadeloupe, French West Indies) vertical array, recorded between 2008 and 2014, to evaluate the seismic response of sediments. First, we apply seismic interferometry by deconvolution method to compute the in-situ shear wave velocity between the sensor at the surface and the two shallow sensors located at GL-15m and GL-39m depth. The efficiency of this method is discussed by studying the variability of the velocity profile obtained and comparing with the in-situ geophysical survey of the site. Computed strains between sensors remain very weak...
Source: Physics and Chemistry of the Earth, Parts ABC - February 27, 2017 Category: Science Source Type: research

Green space water use and its impact on water resources in the capital region of China
Publication date: Available online 24 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Mi Feng (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - February 23, 2017 Category: Science Source Type: research

Remote sensing leaf water stress in coffee (Coffea arabica) using secondary effects of water absorption and random forests
In this study, we tested the ability of selected wavebands in the VIS/NIR range to predict plant water content (PWC) in coffee using the random forest algorithm. An experiment was set up such that coffee plants were exposed to different levels of water stress and reflectance and plant water content measured. In selecting appropriate parameters, cross-correlation identified 11 wavebands, reflectance difference identified 16 and reflectance sensitivity identified 22 variables related to PWC. Only three wavebands (485nm, 670nm and 885nm) were identified by at least two methods as significant. The selected wavebands were train...
Source: Physics and Chemistry of the Earth, Parts ABC - February 22, 2017 Category: Science Source Type: research

Evaluating the influence of the Red Edge band from RapidEye sensor in quantifying leaf area index for hydrological applications specifically focusing on plant canopy interception
Publication date: Available online 22 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Timothy Dube, Onisimo Mutanga, Mbulisi Sibanda, Cletah Shoko, Abel Chemura Reliable and accurate quantification of plant Leaf Area Index (LAI) is critical in understanding its role in reducing runoff. The main aim of the present study was to evaluate the ability of the Red Edge (RE) band derived from RapidEye in estimating LAI for applications in quantifying canopy interception at landscape scale. To achieve this objective, the study also compares the predictive power of two machine learning algorithms (Ra...
Source: Physics and Chemistry of the Earth, Parts ABC - February 21, 2017 Category: Science Source Type: research

Interaction processes at the concrete-bentonite interface after 13 years of FEBEX-Plug operation. Part II: Bentonite contact
Publication date: Available online 20 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Raúl Fernández, Elena Torres, Ana I. Ruiz, Jaime Cuevas, María Cruz Alonso, José Luis García Calvo, Enrique Rodríguez, María Jesús Turrero The in situ FEBEX experiment performed at the URL in Grimsel (Swizerland) was dismantled after 18 years of operation. Interface samples between bentonite and a shotcreted concrete plug that was constructed in a second operational phase have been studied after 13 years of interaction. Mineralogical and geochemical c...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Evaluation of drought using SPEI drought class transitions and log-linear models for different agro-ecological regions of India
In this study, the probabilities of drought class transition, the mean residence time, the 1, 2 or 3 months ahead prediction of average transition time between drought classes and the drought severity class have been derived. The seasonality of precipitation has been derived for non-homogeneous Markov chains which could be used to explain the effect of the potential retreat of drought. Quasi-association and Quasi-symmetry log-linear models have been fitted to the drought class transitions derived from SPEI-12 time series. The estimates of odds along with their confidence intervals were obtained to explain the progression o...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Evaluation of Satellite and simulated rainfall products for hydrological applications in the Notwane Catchment, Botswana
Publication date: Available online 21 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): P.K. Kenabatho, B.P. Parida, D.B. Moalafhi In semi-arid catchments, hydrological modelling, water resources planning and management are hampered by insufficient spatial rainfall data which is usually derived from limited rain gauge networks. Satellite products are potential candidates to augment the limited spatial rainfall data in these areas. In this paper, the utility of the Tropical Rainfall Measuring Mission (TRMM) product (3B42 v7) is evaluated using data from the Notwane catchment in Botswana. In ad...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Remote sensing of surface water quality in relation to catchment condition in Zimbabwe
In this study, we used remotely sensed Normalised Difference Vegetation Index (NDVI) to assess how catchment condition varies within and across river catchments in Zimbabwe. We then used non-linear regression to test whether catchment condition assessed using the NDVI is significantly (α = 0.05) related with levels of Total Suspended Solids (TSS) measured at different sampling points in thirty-two sub-catchments in Zimbabwe. The results showed a consistent negative curvilinear relationship between Landsat 8 derived NDVI and TSS measured across the catchments under study. In the drier catchments of the country, 98% of...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Evaluating the performance of the newly-launched Landsat 8 sensor in detecting and mapping the spatial configuration of water hyacinth (Eichhornia crassipes) in inland lakes, Zimbabwe
This study therefore sought to explore the potential of the recently-launched Landsat 8 OLI/TIRS sensor in mapping invasive species in inland lakes. Specifically, the study compares the performance of the newly-launched Landsat 8 sensor, with more advanced sensor design and image acquisition approach to the traditional Landsat-7 ETM+ in detecting and mapping the water hyacinth (Eichhornia crassipes) invasive species across Lake Chivero, in Zimbabwe. The analysis of variance test was used to identify windows of spectral separability between water hyacinth and other land cover types. The results showed that portions of the v...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Formation of magnesium silicate hydrates (M-S-H)
Publication date: Available online 21 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Ellina Bernard, Barbara Lothenbach, Daniel Rentsch, Isabelle Pochard, Alexandre Dauzères The formation of magnesium silicate hydrates (M-S-H) with MgO to SiO2 ratios from 0.7 to 1.6 has been studied at 20, 50 and 70°C. TGA and XRD data reveal that initially brucite and M-S-H are formed while amorphous silica is still present as indicated by FT-IR and 29Si MAS NMR experiments. In this first step M-S-H with Mg/Si ∼ 1 with pH values ∼ 9.4 is formed independently of the total Mg/Si. Investig...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Zeolite formation in the presence of cement hydrates and albite
Publication date: Available online 21 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Barbara Lothenbach, Ellina Bernard, Urs Mäder Zeolite formation caused by interactions between cement hydrates and rock forming minerals was investigated by two sets of batch experiments and supported by thermodynamic modelling. The first set of batch experiments investigated the interaction between calcium silicate hydrates (C-S-H) (Ca0.8SiO2.8·32H2O) and ettringite (Ca6Al2(SO4)3(OH)12(H2O)26) as cement hydrate minerals and albite (NaAlSi3O8) as a rock forming mineral at 20, 50 and 80°C. T...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Providing peak river flow statistics and forecasting in the Niger River basin
In this study, we use discharge observations, a hydrological model (Niger-HYPE) and extreme value analysis to estimate peak river flow statistics (e.g. the discharge magnitude with a 100-year return period) across the Niger River basin. To test the model’s capacity of predicting peak flows, we compared 30-year maximum discharge and peak flow statistics derived from the model vs. derived from nine observation stations. The results indicate that the model simulates peak discharge reasonably well (on average +20%). However, the peak flow statistics have a large uncertainty range, which ought to be considered in infrastr...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research

Modelling of cementitious backfill interactions with vitrified intermediate-level waste
Publication date: Available online 21 February 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Graham Baston, Timothy Heath, Fiona Hunter, Stephen Swanton New types of wasteform are being considered for the geological disposal of radioactive intermediate-level waste (ILW) in the UK. These include vitrified ILW products arising from the application of thermal treatment processes. For disposal of such wasteforms in a geological disposal facility, a range of concepts are under consideration, including those with a high-pH cementitious backfill (the NRVB, Nirex Reference Vault Backfill). Alternatively, ...
Source: Physics and Chemistry of the Earth, Parts ABC - February 20, 2017 Category: Science Source Type: research