Soil core samples

In Table 7, a comparison of actual measurements, and also two well-known pedo-transfer functions, can be found by depth. It is important to note that there is a large difference in water content between the disturbed soil core samples and the undisturbed samples. Additionally, the two pedo-transfer functions also exhibit a large difference in predicted water content. Therefore, when doing calculations or trying... 

To determine Paraquat in soil Payne et al. [180] separate the sediment from the sample (2L) by adding calcium chloride to aid flocculation, leaving the mixture overnight in a refrigerator for the sediment to settle, then decanting and filtering through a Whatman No. 42 paper under suction on a Buchner funnel. The wet sediment and soil core samples, are mixed for 4h... 

Soil core data are available for only six of the pesticides discussed in this paper. The six pesticides are aldlcarb atrazlne 1,2-dibromo-3-chloropropane (DBCP) 1,2-dlchloropro-pane (DCP) 1,2-dlbromoethane (EDB) and slmazlne. Cores were always sampled at depths greater than one meter and the soil was characterized physically and chemically. The importance of soil core sampling in pesticide leaching assessments is presented in the Discussion section. 

DBCP has been found In ground water In Hawaii, California, Arizona, South Carolina, and Maryland (5-7,19,77-79). Typical positives are 0.02-20 ppb. Areas with the highest frequency of positives and the highest well concentrations are the San Joaquin Valley In California and the region southwest of Phoenix, Arizona. The Hawaii contamination has occurred despite several hundred feet of overburden between the basal aquifer and the surface. One set of California soil core results show that ppb amounts of DBCP has leached about 15 m through the unsaturated zone ( ), whereas DBCP was not detected In another set of California soil cores sampled as deep as 10 m and five years after the last application (80). The latter results can possibly be explained by rapid movement of DBCP down the soil profile to depths greater than 10 m. 

All values are averages of 2 replicate 0-3" soil core samples. Recoveries ranged from 67-129% (mean = 92.7% 14.1)... 

North Bull Island salt marsh, Dublin Bay, Ireland top 20 cm of soil core samples Norway surface sediments in 210 lakes... 

Two field experiments investigating the mobility of pesticides leached by sprinkler irrigation are discussed. The first experiment applied a pulse of chloride and napropamide, a moderately adsorbed herbicide, to a 0.6 ha field which was subsequently leached with 25 cm water low in chloride over a two-week period. Soil core samples were taken at 36 locations to 300 cm and were analyzed in 10 cm increments for chloride and pesticide. Oistribution coefficient measurements were made at each sampling location by hatch equilibrium and column flow through methods. 

At various times, soil core samples were taken, carefully sectioned, and analyzed for TCDD. 

On August 7, 198 the experiments in plots A, B, and D were established. Two soil core samples were taken from plots A, B, C, and D on August 8, 1984. On August 24, 1984 the experiments in plot C were established. The nursery dirt used in this experiment was purchased from a local nursery and contained no TCDD at a detection limit of 1 ppt by weight. On October 9, 1984 a soil core was taken from Plot C... 

Soil core samples are collected at several depth intervals to approximately 50 cm depth using for example a 25 x 25 cm sampling grid plan. 

Yoshida, S., Muramatsu, Y, Tagami, K. (2001). Determination of uranium isotopes in soil core samples collected on JCO grounds after the criticality accident. Environ. Set Technol. 35,4174-4179. 

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