Decomposition influences carbon and nutrient cycling from crop residues. The nylon-mesh-bag technique was implied to study the decomposition N-release dynamics different residues under field conditions. four types of were: maize (lower than 50% below cob), wheat 25% stubbles), a whole mung bean residue, mixture + residue (1:1 ratio) put on soil surface in sub-surface. N release both at-surface-...

in this assay, edible cattle tissues from local markets of ardabil, a province of iran, were examined for residues of tetracycline antibiotics (tetracycline, oxytetracycline and chlortetracycline). in total, 110 samples of triceps, gluteal muscle, diaphragm, kidney and liver were randomly obtained from the local markets of the city of ardabil. solid-phase extraction (spe) and high-performance l...

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Agricultural crop rotations have been shown to increase soil carbon (C), nitrogen (N), and microbial biomass. The mechanisms behind these increases remain unclear, but may be linked to the diversity of crop residue inputs to soil organic matter (SOM). We used a residue mixture incubation to examine how variation in longterm diversity of plant communities in agroecosystems influences decompositi...

Poultry treated with pharmaceutical products can produce eggs contaminated with drug residues. Such residues could pose a risk to consumer health. The following is a review of the information available in the literature regarding drug pharmacokinetics in laying hens, and the deposition of drugs into eggs of poultry species, primarily chickens. The available data suggest that, when administered ...

velocities for soil erosion supports management guidelines (Hagen, 1996; Nielsen and Aiken, 1998; McMaster Standing senescent stems increase the aerodynamic roughness of et al., 2000). Effects of standing stems on eddy diffusion the surface, reducing wind energy available for momentum transfer at affect convective transport of heat, water vapor, and the soil surface, such as for wind erosion, a...

This paper presents the results of the audit on pesticide residues in cereal grains throughout Poland in 2013. The number of all samples of cereal grains was 380. Altogether 292 active substances of plant protection products were checked in the audit. Qualitative and quantative analyses were done according to Polish Standard PN-EN 15562:2008, using the LC-MS/MS technique. The methods (QuEChERS)...

1. Research in agricultural ecosystems is uncovering how the management of crop fields leads to the delivery of transgenic crop residues to adjacent waterways. Aquatic consumers encountering this material may be reduced in abundance and ⁄or limit their feeding activity, subsequently altering organic matter breakdown rate, which is a key ecosystem process in streams. 2. We investigated the effec...

Leaching losses of N are a major limitation of crop production on permeable soils and under heavy rainfalls as in the humid tropics. We established a field trial in the central Amazon (near Manaus, Brazil) in order to study the influence of charcoal and compost on the retention of N. Fifteen months after organic-matter admixing (0–0.1 m soil depth), we added 15N-labeled (NH4)2SO4 (27.5 kg N ha–...

We describe trends in maternal employment and leave-taking after birth of a newborn and analyze the extent to which these behaviors are influenced by parental leave policies. Data are from the June Current Population Survey (CPS) Fertility Supplements, merged with other months of the CPS, and cover the period 1987 to 1994. This time span is one during which parental leave legislation expanded a...