The sandfly Lutzomyia longipalpis (Lutz & Neiva) vectors leishmaniasis in the neotropics. Although much is known about the biology of adult flies, little is known about interactions with its natural enemies. Here, we examined behavior of larvae of L4 L. longipalpis on a soil substrate when exposed to the fire ant Solenopsis invicata (Westwood). When ants were absent, most larvae tended to remai...

abstract soil microbial activity and biochemical processes are often limited by carbon availability in arid- and semi-arid regions, probably due to the low organic matter content. consequently, return of plant residues to soil is a convenient and effortless practice for increasing microbial activities and biochemical reactions. the primary objective of this study was to evaluate the effect of v...

The original focus of this study was an analysis of proteolytic enzyme activity of Alaskan arctic tundra soils, however initial results raised questions regarding the method (Watanabe and Hayano, 1995). Thus, the goals of the study changed to 1) an investigation of the method, and 2) a comparison of enzyme activities of two different soil layers from the arctic tundra. Methodological examinatio...

Each fortified and control sample, moistened to 40~ saturation, was inoculated and kept in an enameled tray loosely covered with a glass plate to retard water evaporation, substrate volatilization, and photodecomposition. Thus, the substrates would be subject to possible microbial degradation, chemical degradation, and adsorption to soil colloids, but not losses due to leaching or soil transpor...

Without exogenous rock-derived nutrient sources, terrestrial ecosystems may eventually regress or reach a terminal steady state, but the degree to which exogenous nutrient sources buffer or slow to a theoretical terminal steady state remains unclear. We used strontium isotope ratios (Sr/Sr) as a tracer and measured Sr/Sr values in aeolian dust, soils, and vegetation across a well-constrained 3M...

The global AsIII-oxidizing activity of microorganisms in eight surface soils from polluted sites was quantified with and without addition of organic substrates. The organic substances provided differed by their nature: either yeast extract, commonly used in microbiological culture media, or a synthetic mixture of defined organic matters (SMOM) presenting some common features with natural soil o...

Land use changes strongly impact soil functions, particularly microbial biomass diversity and activity. We hypothesized that the catabolic respiration response of the microbial biomass would differ depending on land use and that these differences would be consistent at the landscape scale. In the present study, we analyzed the catabolic response profile of the soil microbial biomass through sub...

White rot fungi (WRF) are known to have the ability to degrade organic pollutants with a structure similar to lignin. Because of this, the degradation of polychlorinated biphenyls (PCBs) congeners no. 28, 52, 101, 138, 153 and 180 by substrate before fruiting (substrate) and/or after fruiting (SMS) from cultivated mushrooms Pleurotus ostreatus, Lentinula edodes and Agaricus bisporus was examine...

Ammonia-oxidizing microbes control the rate-limiting step of nitrification, a critical ecosystem process, which affects retention and mobility of nitrogen in soil ecosystems. This study investigated substrate (NH4þ) and nutrient (K and P) limitation of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in temperate forest soils at Coweeta Hydrologic Laboratory, a long-term eco...