Cogent Geoscience最新文献

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Mapping and characterization of salt-affected and waterlogged soils in the Gangetic plain of central Haryana (India) for reclamation and management 哈里亚纳邦(印度)中部恒河平原盐渍和涝渍土壤的制图和特征,用于复垦和管理
Cogent Geoscience Pub Date : 2016-08-19 DOI: 10.1080/23312041.2016.1213689
A. Mandal
{"title":"Mapping and characterization of salt-affected and waterlogged soils in the Gangetic plain of central Haryana (India) for reclamation and management","authors":"A. Mandal","doi":"10.1080/23312041.2016.1213689","DOIUrl":"https://doi.org/10.1080/23312041.2016.1213689","url":null,"abstract":"Abstract IRS LISS III Resource SAT data (2005–07) were integrated with ground truth and soil studies for delineation and characterization of salt-affected and waterlogged soils in the Indo-Gangetic plain of central Haryana. The quality appraisal for salty ground water was also conducted prior to its use for irrigation. Such studies are useful for planning reclamation and management of salt-affected soils and poor quality ground water. Strongly sodic soils were easily identified based on the white to yellowish white tones, high spectral and low NDVI values. Waterlogged areas (surface ponding) were detected based on higher absorption in infrared range. Sodic soils with poor quality ground water showed higher reflectance from dry salts during June and freshly precipitated moist salts in March and October. Sodic soils irrigated with normal ground water showed higher cropping density and higher NDVI values. Moderately and slightly sodic soils showed mixed spectral signatures for salt crusts, moderate cropping density and surface wetness. Soil profile studies indicated higher moisture content at sub-surface depths. The presence of iron and manganese mottles indicated the incidences of water stagnation. Soils with high pHs, ESP, and SAR values and showing the dominance of carbonate and bicarbonates of sodium in the saturation extract indicated sodic nature. Significant presence of CaCO3 concretions at 1 m depth, low organic carbon contents, clay illuviation at sub-surface depth are typical features in sodic soil profiles. Water samples with high pH and SAR values and at places high RSC (Residual Sodium Carbonate) content indicated their sodic nature. Gypsum application is recommended for the reclamation of sodic soils and sodic water.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1213689","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091718","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 20
Geospatial approach to study the spatial distribution of major soil nutrients in the Northern region of Ghana 地理空间方法研究加纳北部地区主要土壤养分的空间分布
Cogent Geoscience Pub Date : 2016-07-10 DOI: 10.1080/23312041.2016.1201906
M. Antwi, A. Duker, M. Fosu, R. Abaidoo
{"title":"Geospatial approach to study the spatial distribution of major soil nutrients in the Northern region of Ghana","authors":"M. Antwi, A. Duker, M. Fosu, R. Abaidoo","doi":"10.1080/23312041.2016.1201906","DOIUrl":"https://doi.org/10.1080/23312041.2016.1201906","url":null,"abstract":"Abstract Spatial distribution of soil nutrients is not normally considered for smallholder farms in Ghana resulting in blanket fertilizer application which leads to low efficiencies of some applied nutrients. This study focuses on applying geospatial analyses to map 120 maize farms in 16 districts of the Northern region of Ghana to identify nutrient distribution. Soil samples were taken from these 120 locations and analysed for contents of nitrogen (N), phosphorus (P) and potassium (K). Spatial models of the contents were generated through geostatistical analysis to map the status of N, P and K nutrients across the locations. Study results indicated that proportion of area deficient in N is 97%, P is 72% and K is 12%. Distribution pattern for N and K nutrients were clusters of low or high contents at specific locations; and that of P was random. Outcome of this study could enhance site-specific nutrient recommendation in Ghana.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1201906","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 17
A feasible way to increase carbon sequestration by adding dolomite and K-feldspar to soil 在土壤中添加白云石和钾长石是增加固碳的可行方法
Cogent Geoscience Pub Date : 2016-07-08 DOI: 10.1080/23312041.2016.1205324
Leilei Xiao, Qibiao Sun, Huatao Yuan, Xiaoxiao Li, Y. Chu, Yulong Ruan, Changmei Lu, B. Lian
{"title":"A feasible way to increase carbon sequestration by adding dolomite and K-feldspar to soil","authors":"Leilei Xiao, Qibiao Sun, Huatao Yuan, Xiaoxiao Li, Y. Chu, Yulong Ruan, Changmei Lu, B. Lian","doi":"10.1080/23312041.2016.1205324","DOIUrl":"https://doi.org/10.1080/23312041.2016.1205324","url":null,"abstract":"Abstract In recent years, many researchers have explored various possible ways to slow down the increase in atmospheric CO2 concentration as this process poses a serious threat to mankind’s survival. Mineral weathering is one possible way. Silicate weathering, for example, causes net carbon sequestration and carbonate weathering occurs relatively rapidly. In this study, dolomite and K-feldspar were added to soil to investigate if these minerals can increase carbon sequestration and also improve the available potassium content. The carbon content of amaranth, the organic and inorganic carbon content of the soil, two kinds of enzymes (polyphenol oxidase and urease), and the available potassium content were all tested. The experimental results show that the minerals accelerate the fixation of organic and inorganic carbon in the soil and also promote amaranth growth. Moreover, the available potassium content was increased when K-feldspar was added. Taken together, adding moderate amounts of carbonate and silicate minerals into the soil is found to be an attemptable way of accelerating CO2 fixation and improving the potassium content of soil.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1205324","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 10
Characteristics of soil exchangeable potassium according to soil color and landscape in Ferralsols environment Ferralsols环境中土壤交换性钾随土壤颜色和景观的变化特征
Cogent Geoscience Pub Date : 2016-06-30 DOI: 10.1080/23312041.2016.1199523
B. Koné, Traoré Lassane, Sehi Zokagon Sylvain, Kouassi Kouassi Jacques
{"title":"Characteristics of soil exchangeable potassium according to soil color and landscape in Ferralsols environment","authors":"B. Koné, Traoré Lassane, Sehi Zokagon Sylvain, Kouassi Kouassi Jacques","doi":"10.1080/23312041.2016.1199523","DOIUrl":"https://doi.org/10.1080/23312041.2016.1199523","url":null,"abstract":"Abstract The use of soil color as Munsell data was explored for in situ indication of soil potassium (K) availability toward a friendly method of agricultural land survey. Soil contents of K, calcium, and magnesium were determined for 998 upland soil samples from Côte d’Ivoire (7–10°N). Soil depths (0–20, 20–60, 60–80, and 80–150 cm), redness ratio (RR), and redness factor (RF) were considered. Significant association was observed between K-levels (high, medium, and low) in topsoil and its color hue, and the highest cumulative frequency of 2.5YR in high and medium levels was characterizing the hill slope position (summit and upper slope). Deep horizon, foot slope, and yellowish color (7.5YR and 10YR) were more relevant to low K-level. Significant linear regressions of soil content of K were observed according to both redness indices indifferently to the topographic positions and soil depths in some extend. Of these finding in the line of folk knowledge, RR and RF are recommended for in situ measurement of soil K, and 2.5YR as color hue may be use as indicator of K-enriched soil at hill slope position.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1199523","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Dynamic response based empirical liquefaction model 基于动力响应的经验液化模型
Cogent Geoscience Pub Date : 2016-06-14 DOI: 10.1080/23312041.2016.1190264
S. Pathak, A. Dalvi
{"title":"Dynamic response based empirical liquefaction model","authors":"S. Pathak, A. Dalvi","doi":"10.1080/23312041.2016.1190264","DOIUrl":"https://doi.org/10.1080/23312041.2016.1190264","url":null,"abstract":"Abstract Dynamic response-based methodology, wherein integrated effect of dynamic soil properties and ground motion parameters proposed by authors, has been found to detect liquefaction susceptibility. The present work necessarily deals with the formulation of a comprehensive empirical liquefaction model (ELM) using this methodology. The absolute form of the ELM is dimensionally homogeneous and yields a correlation between proposed “liquefaction potential term” and “normalized standard penetration blow count corrected for fines content, .” The developed ELM demonstrates unbiased performance when verified over a wide range of significant parameters. One of the prominent features of the present ELM is accurate prediction of possibility of liquefaction. The proposed ELM has proven to work well on varied data-sets of more than 1000 case records within the given range of model parameters. Moreover, the dynamic response-based ELM proves its ability when compared with other liquefaction evaluation procedures. Thus, a generalized and optimistic ELM simulating realistic field conditions is formulated. It is anticipated that for accurate prediction of liquefaction occurrence, it would be more appropriate to employ the proposed ELM which will minimize the enormous losses caused due to liquefaction.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1190264","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091658","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Sedimentological study of Lake Nasser; Egypt, using integrated improved techniques of core sampling, X-ray diffraction and GIS platform 纳赛尔湖沉积学研究;利用岩心取样、x射线衍射和GIS平台的综合改进技术
Cogent Geoscience Pub Date : 2016-04-20 DOI: 10.1080/23312041.2016.1168069
Hussien ElKobtan, M. Salem, K. Attia, Sayed M. Ahmed, Islam Abou El-Magd
{"title":"Sedimentological study of Lake Nasser; Egypt, using integrated improved techniques of core sampling, X-ray diffraction and GIS platform","authors":"Hussien ElKobtan, M. Salem, K. Attia, Sayed M. Ahmed, Islam Abou El-Magd","doi":"10.1080/23312041.2016.1168069","DOIUrl":"https://doi.org/10.1080/23312041.2016.1168069","url":null,"abstract":"Abstract Lake Nasser is one of the largest man-made reservoirs, that is located on the Nile River. To understand the sedimentation process of the lake, bottom sediments from the bottom-surface of the lake core samples from the top 1.25 m of the bottom layer were collected. These samples were mechanically analysed in the laboratory. The analysis of statistical parameters of the sediment samples has generally classified the lake into two depositional environments that reflect the sedimentation process; (1) the riverine environment that exist at the entrance of the lake between El-Daka and CC stations, (2) the lacustrine environment that extend along the rest of the lake to the High Aswan Dam. Along the riverine environment, the river processes were the prevailing, which being reflected on the bottom sediments that are nearly free from clay and composed mainly of sand (>87%) mixed with small ratios of silt (<10%). Further downstream to the end of the lake the lacustrine environment is dominating with slow deposition from quite water with bottom sediments free of sand and the bottom sediments composed mainly of clay (>57%). X-ray analysis indicated that montmorillonite, kaolinite and illite are the dominant clay minerals. GIS was used to spatially simulate the bottom sediment distribution at the bottom of the lake.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1168069","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 9
Assessing the potential of remote sensing to discriminate invasive Asparagus laricinus from adjacent land cover types 遥感识别入侵松柏与邻近土地覆被类型的潜力评估
Cogent Geoscience Pub Date : 2016-03-16 DOI: 10.1080/23312041.2016.1154650
Bambo Dubula, S. Tesfamichael, I. Rampedi
{"title":"Assessing the potential of remote sensing to discriminate invasive Asparagus laricinus from adjacent land cover types","authors":"Bambo Dubula, S. Tesfamichael, I. Rampedi","doi":"10.1080/23312041.2016.1154650","DOIUrl":"https://doi.org/10.1080/23312041.2016.1154650","url":null,"abstract":"Abstract The utility of remote sensing technique to discriminate Asparagus laricinus from adjacent land cover types using a field spectrometer data was explored in this study. Analysis made use of original spectra and spectra simulated based on Landsat and SPOT 5 bands. Comparisons were made at individual and plot levels using original spectra, and individual and group level using simulated spectra. The near-infrared region showed consistent significant differences between A. laricinus and adjacent land cover types at the individual level analysis. In particular, Landsat- and SPOT 5-simulated spectra showed significant differences in only the NIR band. The findings suggest the potential of upscaling field-based data into airborne or spaceborne remote sensing techniques with more emphasis on the NIR band. However, more studies need to be undertaken that will make up for the shortcomings encountered in this study. In this regard, improvements can be made using large number of samples, stratifying target plants according to phenologies, and taking spectral measurements at ideal times as much as possible. Furthermore, laboratory measurements would help in drawing up conclusive statements on the discriminability of the species.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1154650","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 7
Dynamics of soil organic carbon stocks in the Guinea savanna and transition agro-ecology under different land-use systems in Ghana 加纳不同土地利用制度下几内亚稀树草原土壤有机碳储量动态及转型农业生态
Cogent Geoscience Pub Date : 2016-02-18 DOI: 10.1080/23312041.2016.1140319
E. Bessah, A. Bala, S. Agodzo, A. Okhimamhe
{"title":"Dynamics of soil organic carbon stocks in the Guinea savanna and transition agro-ecology under different land-use systems in Ghana","authors":"E. Bessah, A. Bala, S. Agodzo, A. Okhimamhe","doi":"10.1080/23312041.2016.1140319","DOIUrl":"https://doi.org/10.1080/23312041.2016.1140319","url":null,"abstract":"Abstract This study was to assess and predict soil organic carbons stocks (SOCS) under the major land use/cover types in Kintampo North Municipal located in the Guinea savanna through the transition agro-ecological zone of Ghana. Random field sampling was done on 34 plots and 24 sample points at depths 0–10 cm, 10–20 cm and 20–30 cm per plot with soil corer. Soil bulk density, pH, particle size distribution and SOC were determined using standard laboratory procedures and computations. Results were subjected to both statistical and Geo-statistical analyses. The SOCS in each land use decreased with depth. The mean SOC for the five land-use systems studied were 11.33 t/ha, 7.95 t/ha and 6.08 t/ha at 0–10 cm, 10–20 cm and 20–30 cm, respectively. The vertical variability in SOC distribution across the considered land use/cover types was statistically significant (p < 0.05) but the statistical difference amongst land use/cover types was insignificant. The determined mean SOCS were 30.02 (±13.20) t/ha for savanna woodland as the highest and 22.01 (±8.92) t/ha for cashew plantation as the lowest at total depth (0–30 cm). The spatial distribution of SOC stocks ranged between 12 t/ha to about 33 t/ha.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1140319","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 28
Review of preprocessing techniques used in soil property prediction from hyperspectral data 高光谱数据预测土壤性质的预处理技术综述
Cogent Geoscience Pub Date : 2016-02-16 DOI: 10.1080/23312041.2016.1145878
S. Minu, Amba Shetty, Binny Gopal
{"title":"Review of preprocessing techniques used in soil property prediction from hyperspectral data","authors":"S. Minu, Amba Shetty, Binny Gopal","doi":"10.1080/23312041.2016.1145878","DOIUrl":"https://doi.org/10.1080/23312041.2016.1145878","url":null,"abstract":"Abstract Soil properties are neither static nor homogenous with space and time. Capturing the spatial variation of soil properties through conventional methods is a difficult task. Hyperspectral remote sensing data provide rich source of information produced in the form of spectrum at each pixel which can be used to identify surface materials. Airborne and spaceborne narrowband hyperspectral sensors have come to the fore which provides spectral information across large area. Thus, it is a promising tool for studying soil properties and can be used as an alternative to conventional method. But atmospheric attenuation and low signal to noise ratio are major problems with this type of data. Preprocessing of hyperspectral airborne/spaceborne data is required to extract soil properties. This paper reviews previous studies on prediction of soil properties from hyperspectral airborne and satellite data during the past years and the preprocessing techniques used in these predictions.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2016.1145878","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091619","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 15
Modelling rainfall trends in England and Wales 模拟英格兰和威尔士的降雨趋势
Cogent Geoscience Pub Date : 2016-02-01 DOI: 10.1080/23312041.2015.1133218
T. Mills
{"title":"Modelling rainfall trends in England and Wales","authors":"T. Mills","doi":"10.1080/23312041.2015.1133218","DOIUrl":"https://doi.org/10.1080/23312041.2015.1133218","url":null,"abstract":"Abstract The monthly England and Wales precipitation (EWP) series (once power transformed to induce symmetry and to stabilise variance) may be characterised as having linear seasonal trends with a white noise error process superimposed. However, these trends are not stable, for they are interrupted by four regime shifts occurring in 1828, 1871, 1917 and 1976. If these shifts are ignored then the series is consistent with a trend pattern in which winters are becoming increasingly wet and summers drier. If only the last regime from 1976 is considered, then summers are still becoming drier but winters have no trend, with spring becoming wetter. The unusually wet winter of 2014 is seen to have been a consequence of very high January and February rainfall relative to that predicted, the conjunction of which is unprecedented during the two and a half centuries over which the EWP series has been available, during which time such pairs of values have been essentially uncorrelated.","PeriodicalId":42883,"journal":{"name":"Cogent Geoscience","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2016-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23312041.2015.1133218","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60091550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
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