Evaluation of ecosystem service based on scenario simulation of land use in Yunnan Province
Publication date: Available online 26 December 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Hong Zhang, Xiaoli Liao, Tianlin Zhai Climate change and rapid urbanization are important factors restricting future land use. Situational analysis, as an important foundation for the optimization of land use, needs to focus on the impact of climate factors and socio-economic factors. In this paper, the Markov model and the DLS (Simulation of Land System Dynamics) model are combined for the first time, and the land use pattern in 2020 is simulated based on the data of land use in 2000 and 2010 as well as t...
Source: Physics and Chemistry of the Earth, Parts ABC - December 26, 2017 Category: Science Source Type: research

Validation and verification of lawful water use in South Africa: An overview of the process in the KwaZulu-Natal Province.
The objective of the process is to determine how much water is allocated for: (1) existing lawful use in accordance with specific requirements of the NWA, and; (2) current water uses. The process identified users with or without registered use entitlements, whether claims for registered uses were correct, under-estimated, over-estimated or false; and confirmed the lawfulness of each water use in accordance with water legislation that pre-dated the NWA. The process included identifying land and non-land based water uses (industrial, mining and bulk potable water supplies, irrigation, crop types and impoundments) using remot...
Source: Physics and Chemistry of the Earth, Parts ABC - December 25, 2017 Category: Science Source Type: research

Physical and Economic Processes of Ecosystem Services Flows
Publication date: October 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volume 101 Author(s): Hongbo Su, Sudhagar Nagarajan, Jinwei Dong (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - December 16, 2017 Category: Science Source Type: research

Hydro-meteorological trends in the Gidabo catchment of the Rift Valley Lakes Basin of Ethiopia
This study examines the long term hydroclimatic changes, analyses of the hydro-climate variability and detect whether there exist significant trend or not in the Gidabo catchment, rift valley lakes basin of Ethiopia. Precipitation, temperature and stream flow time series data were used in monthly, seasonal and annual time scales. The precipitation and temperature data span is between 1982 and 2014 and that of stream flow is between 1976 and 2006. To detect trends the analysis were done by using Mann Kendal (MK), Sen's graphical method and to detect change point using the Pettit test. The comparison of trend analysis betwee...
Source: Physics and Chemistry of the Earth, Parts ABC - November 16, 2017 Category: Science Source Type: research

Association between forestry ecological engineering and dust weather in Inner Mongolia: A panel study
Publication date: Available online 2 November 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Huang Jixia, Zhang Qibin, Tan Jing, Yue Depeng, Ge Quansheng Forestry ecological engineering projects in Western China include the Three-North Shelter Forest Project (TNSFP), the Natural Forest Protection Project (NFPP), the Grain for Green Project (GGP) and the Beijing-Tianjin Sandstorm Source Project (BTSSP). Such projects play an important role in the control of dust weather in Western China. In this research, data on the frequency of sandstorms, sand-blowing and dust-floating weather, the area of four f...
Source: Physics and Chemistry of the Earth, Parts ABC - November 16, 2017 Category: Science Source Type: research

Projected land use changes impacts on water yields in the karst mountain areas of China
Publication date: Available online 6 November 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Yanqing Lang, Wei Song, Xiangzheng Deng Human-induced land use changes over short time scales have significant impacts on water yield, especially in China because of the rapid social economic development. As the biggest developing country of the world, China's economy is expected to continuously grow with a high speed in the next few decades. Therefore, what kind of land use changes will occur in the future in China? How these changes will influence the water yields? To address this issue, we assessed the w...
Source: Physics and Chemistry of the Earth, Parts ABC - November 16, 2017 Category: Science Source Type: research

Seasonal variations in the water quality of a tropical wetland dominated by floating meadows and its implication for conservation of Ramsar wetlands
We examined the seasonal pattern of water quality of Loktak Lake and compared it with the Keibul Lamjao National Park with a view to suggest measures for removal of this wetland from the Montreux record and for improved conservation. The evaluation of spatio-temporal variations in the water quality parameters over two years was carried out using multivariate statistical analysis. Hierarchical cluster analysis grouped the 11 sampling sites into four groups, less polluted, medium polluted, highly polluted and most polluted and the 12 months into three time periods. Principal Component Analysis identified three factors in the...
Source: Physics and Chemistry of the Earth, Parts ABC - October 7, 2017 Category: Science Source Type: research

Integrated water resources management and infrastructure planning for water security in Southern Africa
Publication date: August 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C, Volume 100 Author(s): Benjamin Mapani, Lapologang Magole, Hodson Makurira, Maideyi Meck, Theresa Mkandawire, Marloes Mul, Cosmo Ngongondo (Source: Physics and Chemistry of the Earth, Parts ABC)
Source: Physics and Chemistry of the Earth, Parts ABC - September 9, 2017 Category: Science Source Type: research

Use of standardized precipitation evapotranspiration index to investigate drought relative to maize, in the Luvuvhu River catchment area, South Africa
Publication date: Available online 7 September 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Teboho Elisa Masupha, Mokhele Edmond Moeletsi Drought frequency and severity analysis during the growing period of maize was carried out by means of the Standardized Precipitation Evapotranspiration Index (SPEI) based on climatic data from seven weather stations (1975–2014). The index was aggregated at different time scales following three consecutive planting dates (October, November and December), relative to the average start of the rainy season in the area. Temporal analysis of droughts was condu...
Source: Physics and Chemistry of the Earth, Parts ABC - September 8, 2017 Category: Science Source Type: research

Field assessment of surface runoff, sediment yield and soil erosion in the opencast mines in Chirimiri area, Chhattisgarh, India
Publication date: Available online 18 July 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): G.K. Nigam, R.K. Sahu, M.K. Sinha, X. Deng, R.B. Singh, P. Kumar Chirimiri Coal field is located in the Koriya district of Chhattisgarh state of India. It lies in the valley of the Hasdeo River and is spread over 125 km2 area. Ever increasing problem of declining forest resources and water quality is a cause of concern particularly due to excessive soil erosion resulting in soil sediment deposition from the overburdened dump. Dwindling resources has compelled the policy makers to search for alternatives s...
Source: Physics and Chemistry of the Earth, Parts ABC - August 10, 2017 Category: Science Source Type: research

Field assessment of surface runoff, sediment yield and soil erosion in opencast mines in Chirimiri area, Chhattisgarh, India
Publication date: Available online 18 July 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): G.K. Nigam, R.K. Sahu, M.K. Sinha, X. Deng, R.B. Singh, P. Kumar Chirimiri Coal field is located in the Koriya district of Chhattisgarh state of India. It lies in the valley of the Hasdeo River and is spread over 125 km2 area. Ever increasing problem of declining forest resources and water quality is a cause of concern particularly due to excessive soil erosion resulting into soil debris deposition from the overburdened dump. Dwindling resources has compelled the policy makers to search for alternative su...
Source: Physics and Chemistry of the Earth, Parts ABC - July 19, 2017 Category: Science Source Type: research

River flow availability for environmental flow allocation downstream of hydropower facilities in the Kafue Basin of Zambia
Publication date: Available online 14 July 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Mulenga Kalumba, Edwin Nyirenda The Government of the Republic Zambia (GRZ) will install a new hydropower station Kafue Gorge Lower downstream of the existing Kafue Gorge Station (KGS) and plans to start operating the Itezhi-Tezhi (ITT) hydropower facility in the Kafue Basin. The Basin has significant biodiversity hot spots such as the Luangwa National park and Kafue Flats. It is described as a Man-Biosphere reserve and the National Park is a designated World Heritage Site hosting a variety of wildlife species...
Source: Physics and Chemistry of the Earth, Parts ABC - July 15, 2017 Category: Science Source Type: research

Balancing water demand for the Heihe River Basin in Northwest China
In this study, we investigated the mutual feedback mechanism between economic systems and eco-hydrological processes in the Heihe River Basin of China with a Water Economic Model (WEM). The WEM is built based on input-output table that embeds water-land resource factors and focuses on the interactive route between water resource and economic elements. On one hand, we investigated the routes and patterns of how eco-hydrological processes acted on economic systems in the upstream of Heihe River Basin, and analyzed how climate change disturbed the economic systems through its impacts on water yield. On the other hand, we expl...
Source: Physics and Chemistry of the Earth, Parts ABC - July 12, 2017 Category: Science Source Type: research

Scenario analysis of land use change in Kabul River Basin – A river basin with rapid socio-economic changes in Afghanistan
Publication date: Available online 5 June 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Omaid Najmuddin, Xiangzheng Deng, Jia Siqi Land use management has a great importance in socio-economic development of countries and regions. Recently, Afghanistan has, at one hand, experienced significant socio-economic changes through political and economic transformation and, on the other hand it is considered amongst vulnerable countries to climate and other natural changes. For this, understanding the interactions between socio-economic and natural changes with land use change under different development s...
Source: Physics and Chemistry of the Earth, Parts ABC - July 11, 2017 Category: Science Source Type: research

Characterization of soil salinization in typical estuarine area of the Jiaozhou Bay, China
In this study, the characteristics of soil salinization and the effects of main land use/land cover and other factors in typical estuarine area of the Jiaozhou Bay are investigated. Soil samples were collected in the parallel coastal zone, vertical coastal zone and longitudinal profile depth in the area to determine the soil salt content. The correlation analysis and principal component analysis are used to address the general characteristics of soil salinization in the study area. In the horizontal direction, there are moderate salinization, severe salinization and saline soil state. The farther from the sea (within 1.1 k...
Source: Physics and Chemistry of the Earth, Parts ABC - June 24, 2017 Category: Science Source Type: research

Impact Assessment of Climate Change on Poverty Reduction: A Global Perspective
This study selects three countries, China, India and Senegal, to investigate the impacts of climate change on poverty reduction. Contrast to previous work what analyze climate changes’ impacts most concentrated on coastal urban areas, this paper is concentrating on the rural poor areas in different income group countries and on a contrastive analysis. The correlation analysis results show the same is that the indicators of climate change are in significant correlations with indicators of poverty and that of agriculture and human well-being in China, India and Senegal. However, China performs poorly in terms of person...
Source: Physics and Chemistry of the Earth, Parts ABC - June 24, 2017 Category: Science Source Type: research

Sensitivity of the mayfly Adenophlebia auriculata (Ephemeroptera: Leptophlebiidae) to MgSO4 and Na2SO4
In this study, the sensitivity of nymphs of the mayfly Adenophlebia auriculata (Ephemeroptera: Leptophlebiidae) was investigated by exposing the organisms to magnesium sulphate (MgSO4) and sodium sulphate (Na2SO4) as models of mining salinisation in short-term (96 hours) and long-term (240 hours) in static system tests. Short-term and long-term lethal concentrations of each salt were estimated using regression analyses. The results indicated that A. auriculata was more sensitive to MgSO4 (LC50 = 3.81 g/L) than Na2SO4 (LC50 = 8.78 g/L). However, this species became sensitive to Na2SO4 (LC10 = 0.19 g/L) but tolerant to MgSO4...
Source: Physics and Chemistry of the Earth, Parts ABC - June 23, 2017 Category: Science Source Type: research

Dynamic characteristics of soil respiration in Yellow River Delta wetlands, China
In this study, the diurnal and seasonal variation of soil respiration rate in the reed wetland land (RL) and the bare wetland land (BL) was measured in situ with the dynamic gas-infrared CO2 method in for seasons, and the factors impacted on the dynamic characteristics of soil respiration were investigated. The results showed that the diurnal variation of soil respiration rate consistently presented a “U” curve pattern in April, July, and September, with the maximum values at 12:00 AM and the minimum values at 6:00 AM. In the same season, the diurnal soil respiration rate in RL was significantly greater than th...
Source: Physics and Chemistry of the Earth, Parts ABC - June 22, 2017 Category: Science Source Type: research

Can Potamonautids be used as umbrella invertebrate species for conservation: identifying opportunities and challenges related to community sustainable livelihoods
In this study, we assessed direct or indirect community livelihoods impacts on the preservation of Potamonautes spp., in the Eastern Highlands region of Zimbabwe and attempted to identify opportunities and constraints to conservation of crabs within the pre-existing livelihoods of community households. Random and snowball sampling methods were used to select households for informal open-ended interviews and participants for the focus group discussions. We found that increasing human populations, poverty, crab consumption, and illegal mining (i.e. resulting in water pollution, degradation of habitats) are threatening freshw...
Source: Physics and Chemistry of the Earth, Parts ABC - June 21, 2017 Category: Science Source Type: research

Diffused impact of grassland degradation over space: A case study in Qinghai province
Publication date: Available online 16 June 2017 Source:Physics and Chemistry of the Earth, Parts A/B/C Author(s): Pei Wang, Xiangzheng Deng, Sijian Jiang Our study aims to simulate and detect the interregional association of livestock production induced by grassland degradation in Qinghai province by TERM (The Enormous Regional Model). The shock variable, grassland degradation, is set and calculated by using its proxy, change of grassland area. We conclude that grassland area is decreasing during 1990-2008 in Qinghai province, and the average reduction rate is 1.591%. And grassland degradation in Qinghai province has a ma...
Source: Physics and Chemistry of the Earth, Parts ABC - June 17, 2017 Category: Science Source Type: research

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