Wet soil microcosms were established to determine effects of organic matter and nitrate additions on microbial respiration and redox potentials. Organic matter (1%) and nitrate (100 ppm and 200 ppm) treatments were applied in factorial combination. Soil pH, redox potential, and CO2 emissions were measured. Data were analyzed by ANOVA for repeated measures and separately by sampling day. Additio...

BACKGROUND The efficacy of pre-emergence herbicides within fields is spatially variable as a consequence of soil heterogeneity. We quantified the effect of soil organic matter on the efficacy of two pre-emergence herbicides, flufenacet and pendimethalin, against Alopecurus myosuroides and investigated the implications of variation in organic matter for weed management using a crop-weed competit...

Organic materials isolated from carbonaceous meteorites provide us with a record of pre-biotic chemistry in the early Solar System. Molecular, isotopic and in situ studies of these materials suggest that a number of extraterrestrial environments have contributed to the inventory of organic matter in the early Solar System including interstellar space, the Solar nebula and meteorite parent bodie...

Organic materials isolated from carbonaceous meteorites provide us with a record of pre-biotic chemistry in the early Solar System. Molecular, isotopic and in situ studies of these materials suggest that a number of extraterrestrial environments have contributed to the inventory of organic matter in the early Solar System including interstellar space, the Solar nebula and meteorite parent bodie...

chickpea (cicer arietinum) is the third most important pulse crop in the world, grown widely across asia and the middle east. weed is one of the main limiting factors in chickpea (cicer arietinum) production. several characteristics of chickpea (cicer arietinum), such as slow plant emergence, short plant height, and chickpea morphology allow weeds to compete effectively. to investigate the effe...

1. We asked whether unionid mussels influence the distribution and abundance of co-occurring benthic algae and invertebrates. In a yearlong field enclosure experiment in a south-central U.S. river, we examined the effects of living mussels versus sham mussels (shells filled with sand) on periphyton and invertebrates in both the surrounding sediment and on mussel shells. We also examined differe...

The aim of this review is to examine the hypothesis that organic matter decreases the adsorption of radiocaesium on clay minerals. The factors that determine radiocaesium mobility and bioavailability in soil are briefly outlined to show why a relationship between soil organic matter content and enhanced Cs bioavailability is paradoxical. In all the investigations reviewed the ionic compositions...

Inputs of leaf litter and other organic matter from the catchment exceed autochthonous production and provide an important food ,resource in most streams (WEBSTER & MEYER 1997, ANDERSON & SEDElL 1979). An experimental long-term exclusion of terrestrial litter inputs to a forested headwater stream (WALLACE et al. 1997) provided an opportunity to determine if the food quality of organic matter wo...

Two digestion experiments and an in situ nylon bag experiment were conducted to determine the correlations between chemical composition, ruminal in situ degradation kinetics and OMI, and OM and CP digestibilities of diets in wethers fed forages of varying nutritive value without and with protein supplementation. Wethers were fed ground corn crop residues, oat-berseem clover or alfalfa hay in th...