Changes in the taxonomic composition of soil bacterial communities under different inter-row tillage managements in a sloping vineyard of the Balaton Uplands (Hungary).

The common grape (Vitis vinifera L.) has been cultivated for thousands of years. Nowadays, it is cultivated using a variety of tillage practices that affect the structure of the soil microbial communities and thus the health of the vine.

Soil-Plant-Water Systems and Interactions.

To comprehend the soil-plant-water system and how its constituents interact with each other, it is essential to better understand its effect on ecosystems [...

Plant Growth and Soil Water Content Changes under Different Inter-Row Soil Management Methods in a Sloping Vineyard.

The main objective of this study was to investigate soil-plant-water interactions based on field measurements of plant reflectance and soil water content (SWC) in different inter-row managed sloping vineyards. The following three different soil management applications were studied: tilled (T), cover crops (CC), and permanent grass (NT) inter-rows. We measured SWCs within the row and between rows of vines.

Microbial Degradation of Different Hydrocarbon Fuels with Mycoremediation of Volatiles.

Naturally occurring microorganisms in soil matrices play a significant role in overall hydrocarbon contaminant removal. Bacterial and fungal degradation processes are major contributors to aerobic remediation of surface contaminants. This study investigated degradation of conventional diesel, heating diesel fuel, synthetic diesel (Syntroleum), fish biodiesel and a 20% biodiesel/diesel blend by naturally present microbial communities in laboratory microcosms under favorable environmental conditions.

Impact of VOC removal by activated carbon on biodegradation rates of diesel, Syntroleum and biodiesel in contaminated sand.

The degradation of conventional diesel (D), synthetic diesel (Syntroleum), and pure fish biodiesel (B100) by indigenous microbes was investigated in laboratory microcosms containing contaminated sand. The fate of volatiles and the influence of volatilization on degradation rates were examined by placing activated carbon (AC) in microcosm headspaces to sorb volatiles. Three AC regimes were compared: no activated carbon (NAC), regular weekly AC change (RAC), and frequent AC change (FAC), where the frequency of activated carbon exchange declined from daily to weekly.

Input of organic matter enhances degradation of weathered diesel fuel in sub-tropical sediments.

We investigated different types of biostimulation practices to enhance degradation of weathered conventional diesel fuel in sandy beach sediments from coastal Alabama. Biodegradation rates were measured following the addition of either inorganic nutrients, or organic matter derived from either plant material (Spartina alterniflora) or fish tissue (Chloroscombrus chrysurus) both common to the region. The greatest hydrocarbon degradation rates were observed in the C.

Effect of concentration gradients on biodegradation in bench-scale sand columns with HYDRUS modeling of hydrocarbon transport and degradation.

The present research investigated to what extent results obtained in small microcosm experiments can be extrapolated to larger settings with non-uniform concentrations. Microbial hydrocarbon degradation in sandy sediments was compared for column experiments versus homogenized microcosms with varying concentrations of diesel, Syntroleum, and fish biodiesel as contaminants. Syntroleum and fish biodiesel had higher degradation rates than diesel fuel.

Influence of inocula with prior hydrocarbon exposure on biodegradation rates of diesel, synthetic diesel, and fish-biodiesel in soil.

To achieve effective bioremediation within short warm seasons of cold climates, microbial adaptation periods to the contaminant should be brief. The current study investigated growth phases for soil spiked with diesel, Syntroleum, or fish biodiesel, using microbial inocula adapted to the specific substrates. For modeling hydrocarbon degradation, multi-phase first order kinetics was assumed, comparing linear regression with nonlinear parameter optimization of rate constants and phase durations.

Impact of crude oil exposure on nitrogen cycling in a previously impacted Juncus roemerianus salt marsh in the northern Gulf of Mexico.

This study investigated potential nitrogen fixation, net nitrification, and denitrification responses to short-term crude oil exposure that simulated oil exposure in Juncus roemerianus salt marsh sediments previously impacted following the Deepwater Horizon accident. Temperature as well as crude oil amount and type affected the nitrogen cycling rates. Total nitrogen fixation rates increased 44 and 194 % at 30 °C in 4,000 mg kg(-1) tar ball and 10,000 mg kg(-1) moderately weathered crude oil treatments, respectively; however, there was no difference from the controls at 10 and 20 °C.

Enhancing the biodegradation of oil in sandy sediments with choline: a naturally methylated nitrogen compound.

We investigated how additions of choline, a naturally occurring methylated nitrogen-containing compound, accelerated hydrocarbon degradation in sandy sediments contaminated with moderately weathered crude oil (4000 mg kg(-1) sediment). Addition of lauroylcholine chloride (LCC) and tricholine citrate (TCC) to oil contaminated sediments resulted in 1.6 times higher hydrocarbon degradation rates compared to treatments without added choline derivatives.

Intrinsic rates of petroleum hydrocarbon biodegradation in Gulf of Mexico intertidal sandy sediments and its enhancement by organic substrates.

The rates of crude oil degradation by the extant microorganisms in intertidal sediments from a northern Gulf of Mexico beach were determined. The enhancement in crude oil degradation by amending the microbial communities with marine organic matter was also examined. Replicate mesocosm treatments consisted of: (i) controls (intertidal sand), (ii) sand contaminated with crude oil, (iii) sand plus organic matter, and (iv) sand plus crude oil and organic matter.

Responses of microbial community from northern Gulf of Mexico sandy sediments following exposure to Deepwater Horizon crude oil.

In the present study, microbial community responses to exposure to unweathered Macondo Well crude oil and conventional diesel in a sandy beach environment were determined. Biodegradation was assessed in mesocosm experiments with differing fuel amounts (2,000 and 4,000 mg/kg) and with or without inorganic nutrient amendment. Carbon dioxide production was measured daily for 42 d.