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Dissolved organic carbon (DOC) provides a reactive substrate that can facilitate the transport of organic and inorganic contaminants in runoff. The aromatic fractions of DOC are especially important since contaminants are preferentially... more
Dissolved organic carbon (DOC) provides a reactive substrate that can facilitate the transport of organic and inorganic contaminants in runoff. The aromatic fractions of DOC are especially important since contaminants are preferentially sorbed onto these fractions. Agricultural practices such as land application of manure can provide substantial inputs of both DOC as well as associated contaminants to agroecosystems. We explored the exports of DOC, estrogens and trace elements in surface runoff from agricultural plots receiving poultry litter. The study was conducted on agricultural soils of the coastal plain in Delaware. Estrogens included free forms: estrone, 17β–estradiol, and estriol; and their glucuronide and sulfate conjugates. Trace elements studied were arsenic, copper, and zinc. Litter treatments included raw litter, pelletized litter and control (no-litter). Treatment plots were 5m wide and 12m long with reduced and no–tillage management practices. The aromatic content of ...
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ABSTRACT Potassium concentrations in irrigation waters varied greatly across different locations in India (spatial), different times of the year (temporal), and different sources of irrigation used. Therefore, local assessment of K... more
ABSTRACT Potassium concentrations in irrigation waters varied greatly across different locations in India (spatial), different times of the year (temporal), and different sources of irrigation used. Therefore, local assessment of K contribution from irrigation water, including K leaching losses, is required in determining field-specific fertiliser K application rate.
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ABSTRACT Land application of manure is a common practice that is used to supplement nutrients from fertilizers as well as to reuse and recycle waste in agricultural watersheds. Excess application of manure can however result in elevated... more
ABSTRACT Land application of manure is a common practice that is used to supplement nutrients from fertilizers as well as to reuse and recycle waste in agricultural watersheds. Excess application of manure can however result in elevated exports of organic and inorganic nutrients in runoff. We evaluated the concentration and composition of dissolved organic matter (DOM) in runoff from cropland (corn) receiving poultry manure. Manure was applied once every three years at the rate of 9 Mg ha−1 in early spring and was incorporated into the soil during application. Surface runoff and soil water sampling was performed for eight natural storm events with one storm event prior to manure application. Samples were collected from the field edge, upland and lowland riparian zones and a receiving stream. Concentrations of dissolved organic carbon (DOC) were highest at the field edge (mean: 94 mg L−1) and then declined sharply for the riparian and stream locations. Temporally, DOC concentrations in field runoff were highest for the first storm event following manure application and then declined quickly over the next 1–3 weeks. DOM composition in runoff following manure application had low aromaticity and a microbial/tryptophan-like character. These characteristics evolved with time toward more aromatic, more humic, and a terrestrial-like DOM composition. The decrease in runoff DOM was attributed to sorption and microbial degradation. Our observations suggest that while concentrations of DOM can be low in manure runoff, a short period (1–3 weeks) following manure application could be an environmentally sensitive and vulnerable period for runoff water quality.
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Research Interests:
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Soil and Sediment Contamination, 20:249260, 2011 Copyright © Taylor & Francis Group, LLC ISSN: 1532-0383 print / 1549-7887 online DOI: 10.1080/15320383.2011.560979 ... Effect of Soil Chemical and Physical Properties ... SUDARSHAN... more
Soil and Sediment Contamination, 20:249260, 2011 Copyright © Taylor & Francis Group, LLC ISSN: 1532-0383 print / 1549-7887 online DOI: 10.1080/15320383.2011.560979 ... Effect of Soil Chemical and Physical Properties ... SUDARSHAN KUMAR DUTTA,1 ...