Soil application of activated hydrochar derived from sewage sludge enhances plant growth and reduces nitrogen loss.

Sewage sludge treatment and disposal is a considerable environmental and economic burden, and is considered a major global challenge. Here, sewage sludge treatment and disposal were studied with a focus on hydrothermal carbonization and the use of hydrochar (HC) as a soil amendment after Fenton-reaction activation. The underlying hypothesis was that enhanced adsorption of nutrients (e.

Soil nitric and nitrous oxide emissions across a nitrogen fertilization gradient in root crops: A case study of carrot (Daucus carota) production in Mediterranean climate.

Insufficient knowledge about soil nitrous and nitric oxide (N2O and NO) emissions from vegetable production limits our ability to constrain their atmospheric budget. Carrots (Daucus carota) are a globally important, heavily managed and irrigated, high-value horticultural crop. Although intensively fertilized carrots may be an important hot-spot source of N2O and NO emissions, we have little information on the response of soil N2O emissions to fertilization and no information on the NO emissions response.

A new open-path eddy covariance method for nitrous oxide and other trace gases that minimizes temperature corrections.

Low-power, open-path gas sensors enable eddy covariance (EC) flux measurements in remote areas without line power. However, open-path flux measurements are sensitive to fluctuations in air temperature, pressure, and humidity. Laser-based, open-path sensors with the needed sensitivity for trace gases like methane (CH ) and nitrous oxide (N O) are impacted by additional spectroscopic effects.

The effects of microalgae-based fertilization of wheat on yield, soil microbiome and nitrogen oxides emissions.

Overuse of agrochemicals is linked to nutrient loss, greenhouse gases (GHG) emissions, and resource depletion thus requiring the development of sustainable agricultural solutions. Cultivated microalgal biomass could provide such a solution. The environmental consequences of algal biomass application in agriculture and more specifically its effect on soil GHG emissions are understudied.

Persistence and spread of tetracycline resistance genes and microbial community variations in the soil of animal corrals in a semi-arid planted forest.

At the spring, goat and sheep herds are transferred to planted forests, in a semi-arid region in the northern Negev Desert, Israel, to reduce herbaceous biomass and, fire risk. The herds are held overnight in corrals for about 4 months, enriching the soil with organic matter and nitrogen. This research examined the effect of these enrichments on soil bacterial community structure (BCS) and the abundance of tetracycline resistance genes (TRGs) in active and abandoned corrals (1-10-years-old).

Environmental Tradeoffs between Nutrient Recycling and Greenhouse Gases Emissions in an Integrated Aquaculture-Agriculture System.

The unlimited nitrogen (N) availability that has characterized crop production in the last few decades is accompanied by environmental burdens, including the greenhouse gas (GHG) emissions associated with fertilizer production, post-application nitrate (NO) pollution of water bodies, and emissions of reactive gaseous N forms into the atmosphere. Here, we quantified the environmental tradeoffs of replacing mineral N fertilizer with NO and ammonium (NH) originating from effluent water of aquaculture in a cucumber () cultivation system. While the yield, nitrogen use efficiency (NUE), and NO leaching were similar between the cucumbers fertilized and irrigated (fertigated) by aquaculture effluent water containing 100 mg of NO-N L (AN), by aquaculture effluent water supplemented with NH (AN+), or by tap water with NO and NH added (FN+), there were significant differences in the nitrous oxide (NO) emissions between the systems.

Empirical Evidence for the Potential Climate Benefits of Decarbonizing Light Vehicle Transport in the U.S. with Bioenergy from Purpose-Grown Biomass with and without BECCS.

Climate mitigation scenarios limiting global temperature increases to 1.5 °C rely on decarbonizing vehicle transport with bioenergy production plus carbon capture and storage (BECCS), but climate impacts for producing different bioenergy feedstocks have not been directly compared experimentally or for ethanol vs electric light-duty vehicles. A field experiment at two Midwest U.

Legacy effects of land use on soil nitrous oxide emissions in annual crop and perennial grassland ecosystems.

Land use conversions into and out of agriculture may influence soil-atmosphere greenhouse gas fluxes for many years. We tested the legacy effects of land use on cumulative soil nitrous oxide (N O) fluxes for 5 yr following conversion of 22-yr-old Conservation Reserve Program (CRP) grasslands and conventionally tilled agricultural fields (AGR) to continuous no-till corn, switchgrass, and restored prairie. An unconverted CRP field served as a reference.

Long-term nitrous oxide fluxes in annual and perennial agricultural and unmanaged ecosystems in the upper Midwest USA.

Differences in soil nitrous oxide (N O) fluxes among ecosystems are often difficult to evaluate and predict due to high spatial and temporal variabilities and few direct experimental comparisons. For 20 years, we measured N O fluxes in 11 ecosystems in southwest Michigan USA: four annual grain crops (corn-soybean-wheat rotations) managed with conventional, no-till, reduced input, or biologically based/organic inputs; three perennial crops (alfalfa, poplar, and conifers); and four unmanaged ecosystems of different successional age including mature forest. Average N O emissions were higher from annual grain and N-fixing cropping systems than from nonleguminous perennial cropping systems and were low across unmanaged ecosystems.

Sustainable bioenergy production from marginal lands in the US Midwest.

Legislation on biofuels production in the USA and Europe is directing food crops towards the production of grain-based ethanol, which can have detrimental consequences for soil carbon sequestration, nitrous oxide emissions, nitrate pollution, biodiversity and human health. An alternative is to grow lignocellulosic (cellulosic) crops on 'marginal' lands. Cellulosic feedstocks can have positive environmental outcomes and could make up a substantial proportion of future energy portfolios.

Carbon debt of Conservation Reserve Program (CRP) grasslands converted to bioenergy production.

Over 13 million ha of former cropland are enrolled in the US Conservation Reserve Program (CRP), providing well-recognized biodiversity, water quality, and carbon (C) sequestration benefits that could be lost on conversion back to agricultural production. Here we provide measurements of the greenhouse gas consequences of converting CRP land to continuous corn, corn-soybean, or perennial grass for biofuel production. No-till soybeans preceded the annual crops and created an initial carbon debt of 10.

Energy efficiency of conventional, organic, and alternative cropping systems for food and fuel at a site in the U.S. Midwest.

The prospect of biofuel production on a large scale has focused attention on energy efficiencies associated with different agricultural systems and production goals. We used 17 years of detailed data on agricultural practices and yields to calculate an energy balance for different cropping systems under both food and fuel scenarios. We compared four grain and one forage systems in the U.

Sulfide-oxidizing activity and bacterial community structure in a fluidized bed reactor from a zero-discharge mariculture system.

In the present work we describe a comprehensive analysis of sulfide oxidation in a fluidized bed reactor (FBR) from an environmentally sustainable, zero-discharge mariculture system. The FBR received oxygen-depleted effluent from a digestion basin (DB) that is responsible for gasification of organic matter and nitrogen. The FBR is a crucial component in this recirculating system because it safeguards the fish from the toxic sulfide produced in the DB.

Diversity of microbial communities correlated to physiochemical parameters in a digestion basin of a zero-discharge mariculture system.

Bacterial community structure and physiochemical parameters were examined in a sedimentation basin of a zero-discharge mariculture system. The system consisted of an intensively stocked fish basin from which water was recirculated through two separate treatment loops. Surface water from the basin was pumped over a trickling filter in one loop while bottom-water was recirculated through a sedimentation basin followed by a fluidized bed reactor in the other.