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Effects of prolonged flooding on the cycling of dissolved inorganic carbon in Plinthosols 长期驱油对复合土中溶解无机碳循环的影响

Geochimica Brasiliensis Pub Date : 2018-07-04 DOI: 10.21715/GB2358-2812.2018321088

N. Silva, A. B. de-Campos

{"title":"Effects of prolonged flooding on the cycling of dissolved inorganic carbon in Plinthosols","authors":"N. Silva, A. B. de-Campos","doi":"10.21715/GB2358-2812.2018321088","DOIUrl":"https://doi.org/10.21715/GB2358-2812.2018321088","url":null,"abstract":"Cultivation of flooded rice has developed in wetlands of the Cerrado Biome as a result of the expansion of the Brazilian agricultural frontier. Changes in soil moisture content due to agricultural practices associated with flood irrigation may induce geochemical transformations in the soil. The present study aimed at investigating the effect of flood irrigation on inorganic carbon cycling through the determination of dissolved inorganic carbon (DIC) concentrations. Incubation experiments under anoxic and reducing conditions were carried out in laboratory with samples of horizons A, AB, Bf1 and Bf2 of Plinthosols profiles from areas under 20 and 30 year of flood irrigation and natural area of the Irrigation Project Luiz Alves do Araguaia, GO, Brazil. Soil samples under flooding were incubated for 1, 7, 15, 30, 60 and 120 days to simulate the effect of prolonged flooding and after incubation the liquid fraction was analyzed for DIC. Higher concentrations of DIC were found in the A horizon (up to 37.2 mg/L) from soil profiles under cultivation, which may be associated with liming or desorption processes of carbon species. DIC correlated with soil electrical conductivity and Eh. It is concluded that solubilization of inorganic carbon is favored by flood irrigation, especially in Plinthosols that have received liming, as well as by the reducing state of the soil and higher concentrations of ions in solution.","PeriodicalId":34597,"journal":{"name":"Geochimica Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46291252","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: 0

Metal Anomaly Prospection at Cerrado. Example for the use of Si-Phytoliths as anomaly indicators at Riacho dos Machado Region, Minas Gerais, Brazil 塞拉多金属异常远景。巴西米纳斯吉拉斯Riacho dos Machado地区硅植硅体作为异常指标的使用示例

Geochimica Brasiliensis Pub Date : 2018-07-04 DOI: 10.21715/gb2358-2812.2018321040

Heloiza Márcia Fernandes-Horn, A. Horn, R. A. Sampaio, M. Rodrigues, L. Duarte, E. Bilal, Hernando Baggio Filho, I. Torres

{"title":"Metal Anomaly Prospection at Cerrado. Example for the use of Si-Phytoliths as anomaly indicators at Riacho dos Machado Region, Minas Gerais, Brazil","authors":"Heloiza Márcia Fernandes-Horn, A. Horn, R. A. Sampaio, M. Rodrigues, L. Duarte, E. Bilal, Hernando Baggio Filho, I. Torres","doi":"10.21715/gb2358-2812.2018321040","DOIUrl":"https://doi.org/10.21715/gb2358-2812.2018321040","url":null,"abstract":"The target area of this work is a heavy metal anomaly in the surroundings of a gold mine and a lead mining complex. This work investigated the distribution of selected heavy elements in soil samples and Si-Phytoliths from plants. The aim was to verify if metal contents are indicative for metal anomalies in the soil. Plants and soil samples were collected in profiles over granitic-gneissic rocks, which form the basement, in tectonized contact with the overlaying sedimentary units belonging to the Riacho dos Machados Group, part of the Espinhaco Super Group. The whole rock substrate is covered by lateritic to arenitic soils with different exposure depths. Metal-rich fluid invaded these units, forming metal anomalies culming in Zn-Pb-Au deposits, like that of Salobre-Porteirinha. After appropriate preparation, the samples were, analyzed by ICP-OES (Si-Phytoliths) and FRX (soil). Anomalies in the investigated profile are indicated by high metal contents in the Si-Phytoliths of the selected species. Using different species the metal concentration in different depths can be determined in a simple and easy way. The Si-Phytolith concentrations seem to reproduce better the rock metal anomalies than the soil samples.","PeriodicalId":34597,"journal":{"name":"Geochimica Brasiliensis","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46529778","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: 0

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