First Year Of Production Research Articles

Produced water geochemistry from hydraulically stimulated Niobrara Formation petroleum wells: Origin of salinity and temporal perspectives on treatment and reuse

Produced water (i.e., a mixture of returned injection fluids and geologic formation brines) represents the largest volumetric waste stream associated with petroleum production in the United States. As such, produced water has been the focus of intense study with emphasis on understanding the geologic origin of the fluids, environmental impacts of unintended or intentional release, disposal concerns, and their commodity (e.g., lithium) potential. However, produced water geochemistry from many active petroleum plays remain poorly understood leading to knowledge gaps associated with the origin of brine salinity and parameters (e.g., radium levels) that can impact treatment, disposal, and possible reuse. Here we evaluate the major ion geochemistry, radium concentrations, and stable water isotope composition of ~120 produced water samples collected from 17 producing unconventional petroleum wells in Weld County, Colorado from the Late Cretaceous Niobrara Formation. This sample set encompasses eight produced water time series from four new wells across production days 0 to ~365 and from four established wells across production days ~1000 to ~1700. Additionally, produced water from nine other established Niobrara Formation wells were sampled at discrete time points ranging from day 458 to day 2256, as well as hydraulic fracturing input fluids. These results expand the available Niobrara Formation produced water geochemical data, previously limited to a few wells sampled within the first year of production, allowing for the heterogeneity of major ions and radium to be evaluated. Specific highlights include: (i) observations that boron and bromide concentrations are higher in produced waters from new wells compared to older, established wells, suggesting the role of input fluids contributing to fluid geochemistry; and (ii) barium and radium concentrations vary between the producing benches of the Niobrara Formation with implications for treating radiological hazards in produced waters from this formation. Furthermore, we explore the geochemical relationships between major ion ratios and stable water isotope composition to understand the origin of salinity in Niobrara Formation brines from the Denver-Julesburg Basin. These findings are discussed with perspective toward potential treatment and reuse of Niobrara produced water prior to disposal.

Responses to foliar sprays of strawberry variety ‘Portola’ to biostimulants on growth, yield, quality, and bioactive compounds

The acceptance of strawberries in international trade has increased due to their organoleptic qualities, high nutritional value, and richness in antioxidants. This research evaluated the effect of foliar spray with chitosan, brassinosteroids, and thidiazuron as metabolic enhancers on growth, productivity, quality parameters, and bioactive compounds in ‘Portola’ strawberry cultivar in the first year of production. This experiment included six treatments and control with doses of CTS of 100, 300, and 400 mg L-1, of Brassinosteroids (Vitazyme™) 0.5, 1-, and 5-mL L-1 and 0.15 mL L-1 of TDZ (Charger plex™) in applications of these biostimulants alone and combination CTS and BRs. The findings indicated that CTS treatments increased plant length, leaf count, leaf area, and fruit firmness. The joint application of CTS and BRs significantly promotes crown diameter, photosynthetic pigments, carotenoids, fresh and dry weight of roots and aerial parts, and ripening. Applications of CTS 300 mg L-1 and 1 mL L-1 of Vitazyme have shown the highest fruit length, diameter, and weight values. Regarding TDZ, this work showed an increase in crown diameter and in the fresh and dry weight of both the root and the aerial part without significant differences in the content of the chlorophyll and titratable acidity compared to the control. Therefore, it could be safely recommended that foliar application with CTS, BRs, and TDZ can be used as biostimulants to improve the growth, quality and bioactive compounds of strawberry cv ‘Portola’.

Genetic analysis of agronomic and physiological traits associated with latex yield revealed complex genetic bases in Hevea brasiliensis

Hevea brasiliensis, a natural rubber producing species, is widely cultivated due to its high rubber yield potential. Natural rubber is synthesised in the rubber particles of laticifers. Latex diagnosis (LD) was established to characterise the physiological state of the laticiferous system by measuring its physiological parameters, i.e., sucrose, inorganic phosphorous (Pi), thiols and total solid content (TSC). Rubber clones are often classified in three groups i.e., quick starters, medium starters and slow starters. To better understand the genetic bases of latex yield, a biparental population was generated from a cross between the quick-starter clone PB 260 and the medium-starter clone SP 217. LD was performed during the peak latex production season and used to calculate sucrose loading. The agronomic and physiological parameters associated with latex yield led to the classification of genotypes according to the rubber clonal typology and to the identification of quantitative trait loci (QTL) using a high-density map. Inorganic phosphorous content was positively associated with yield during the first year of production thus enabling identification of quick-starter clones. In addition, the LD-based clonal typology led to determine the long-term yield potential and the use of appropriate ethephon stimulation. QTL analysis successfully identified several QTLs related to yield, sucrose, Pi and TSC. One QTL related to sucrose loading was identified in the same position as the QTL for sucrose on linkage group 1. To our knowledge, this is the first study to report QTL analysis for this trait. The use of a high-density map enables the identification of genes underlying QTLs. Several putative genes underlying QTLs related to yield, sucrose and TSC were identified.

Productivity and Fruit Quality of ‘FalstaffPBR’ Pear Variety Grafted on Different Rootstocks

‘FalstaffPBR’ is a pear variety released by CREA and New Plant in 2012. This study focused on the effects of various clonal rootstocks on the main productive and qualitative traits of ‘FalstaffPBR’ scion. The rootstocks used were ‘EMC’, ‘EMH’, and ‘BA29’ for quince (Cydonia oblonga) and pear ‘Farold 40’ (Pyrus communis). Plants were planted in 2009 with a layout that, depending on the used rootstock, varied between 60 and 120 cm on the row, according to the rootstock standard planting system, and 350 cm between rows. The average yield calculated in the trail field in the 4 years of production (2014–2017) was over 22.7 tons ha−1 on ‘BA29’, 22.8 tons ha−1 on ‘EMH’, 16.3 tons ha−1 on ‘Farold 40’, and 18.4 on ‘EMC’. Fruits of the plants grafted on ‘Farold 40’ always had a medium-to-high size, while fruits produced by the plants grafted onto ‘BA29’ have been larger in size since the first years of production. The plants grafted onto ‘EMH’ produced fruits with the highest percentage of red overcolor. The ‘EMH’ rootstock is optimal for ‘FalstaffPBR’ as it gives the plant an intermediate vigor between ‘BA29’ and ‘EMC’, and a good yield per hectare from the first planting years; the average fruit size is excellent.

Productivity and economic feasibility of cultivated forage and food crops in the central highlands of Ethiopia

The study was conducted to evaluate the yield performance of improved forage and food crops and to estimate the profitability of fodder and food crops in Holetta and Ejere areas, central highlands of Ethiopia during 2019 and 2020 cropping seasons. The experiment was laid out in randomized complete block design with three replications and evaluated two annual forage crops, two perennial forage crops, and two cereal food crops. Data on herbage dry matter (DM) yield was collected for forage crops while straw and grain yields were measured for food crops. Partial budget analysis was made to evaluate the economic feasibility of forage and food crops production. The result revealed that the herbage DM yield varied (P<0.05) at each location during each production year and combined over years and between the two locations. The straw and grain yields of food crops also varied (P<0.05) between the two production years and locations. The nutritive values of herbage and straw yields of forage and food crops differed (P<0.05) for all measured parameters. The crude protein and in-vitro dry matter digestibility of perennial forage crops were relatively higher than annual forage crops and straw of food crops. The partial budget analysis result indicated that the gross revenue (GR) and net return (NR) obtained from food crops were the highest followed by annual forage crops while the least was recorded from perennial forage crops during the first year of production. However, perennial forage crops produced the higher GR and NR than food crops and annual forage crops in the second year of production. In the second year of production, among the forage crops, Desho grass generated 308, 293, 287, and 232% while Rhodes grass generated 99, 92, 90, and 62% more NR than wheat, sole oat, barley, and oat/vetch mixtures, respectively. The benefit-cost ratio (BCR) of perennial forage crops was the lowest (3.0 for Desho and 1.6 for Rhodes) in the first year of production but the ratio was the highest (17.2 for Desho and 8.6 for Rhodes) in the second year of production. This confirms the better economic feasibility of perennial forage crops as they can be maintained using minimal management cost once they have been established.

Reuse of coir, peat, and wood fiber in strawberry production.

Production of strawberries in greenhouses and polytunnels is gaining popularity worldwide. This study investigated the effect of reuse of coir and peat, two substrates commonly adapted to soilless strawberry production, as well as stand-alone wood fiber from Norway spruce, a promising substrate candidate. The experiment was performed in a polytunnel at NIBIO Apelsvoll, Norway, and evaluated both virgin substrates, as well as spent materials that were used in one or two years. Yield, berry quality and plant architecture of the strawberry cultivar 'Malling Centenary' were registered. In addition, chemical and physical properties of virgin and reused substrates were investigated. While plants grown in peat and wood fiber had highest yield in the first year of production, the berry yield was slightly reduced when these substrates were utilized for the second and third time. However, yield was comparable to the yield level attained in new and reused coir. Interestingly, berries grown in wood fiber had a tendency to a higher sugar accumulation. This substrate also produced the highest plants. Stand-alone wood fiber was the substrate with the highest accumulation of nitrogen during the three consecutive production cycles. All three investigated materials revealed a trend for decreased potassium accumulation. Wood fiber is characterized by the highest percentage of cellulose, however after three years of production the cellulose content was reducedto the same levels as for coir and peat. Implementation of wood fiber as a growing medium, as well as general practice of substrate reuse can be therefore an achievable strategy for more sustainable berry production.

Fertigacija borovnice gajene u saksijama - primer slučaja fertigacije borovnice u Nemenikućama

The aim of this research is to present the technology of blueberry cultivation, especially from the aspect of fertilization and irrigation (fertigation), and the water use efficiency obtained in blueberry plantations grown in pots. In order to obtain optimal yields, irrigation and nutrition of the plants must be well coordinated, which is shown in this work. The experiment was located in Nemenikuća, Sopot municipality. The location is suitable for blueberry cultivation due to topography, altitude, climatic factors and water supply. Blueberries were planted in 45-liter pots, which was sufficient to obtain high yields. The substrate used was "Legro" with 25% perlite. Dripper with a flow rate of 4 L and a divided sub-dropper for uniform distribution of water in the pot was used. The irrigation system was also equipped with devices that extract the appropriate amount of fertilizer from the tank over the set of pH and EC values. This way of water distribution enables precise control of the quality and parameters of the irrigation water, such as pH and electrical conductivity (EC). Good drainage of the pot is ensured by perforations of the bottom and sides of the pot with several openings of different sizes and shapes. It is desirable that the bottom of the pot is separated from the substrate. The amount of water used for vegetation was 2,817,700 L or 2817.7 m3 of water for 9,000 plants. A yield of 14,000 kg of blueberries was obtained in second year and 38.000 kg in the third growing year. This means that 201.21 L of water was used for the yield of 1 kg of blueberries or 4.96 kg of blueberry can be produced using 1 m3 of water. Most of the water was applied in July (92 L per pot). The EC of the solution was variable from day to day, depending on the amount of nutrients consumed by blueberry. Water consumption was determined partly by the duration of irrigation and by the amount of drained water. The pH and EC values of the water were measured daily. The pH in the irrigation water was maintained in the range of 5.0-5.5 and the ES of 1.3-2.5 dS/m, in the drainage water 0.6 to 2.3 dS/m. In the year of replanting 77 g of yield per plant wwas obtained. Very high yields, as high as 1.5 kg per plant were obtained in the first year of production and as high as 4.2 kg per plant in the second year of production. The average water consumption during the growing season was 3 L per plant, and total water consumption during first yielding year was 313 L.

Compost application boosts soil restoration in highly disturbed hillslope vineyard

A field trial was carried out to investigate the effects of compost application on a young Cabernet sauvignon vineyard located in a hilly area in the North-East of Italy and subjected to land terracing before plantation. The use of a compost based on manure, pruning residues and pomace at a rate of 65 t ha-1 was compared to the mineral fertilization regime recommended for the vineyards in the area (NPK: 80, 50, 200 kg ha-1). A multi-factorial approach that considered soil chemical properties, microbial community structure and function, vine nutritional and vegetative indexes, yield and quality parameters was applied in the attempt of depict interrelated effects of compost on all these factors. Results of this study show that the application of compost for three consequent years greatly increased soil organic matter content and improved the mineral nutrient availability in the soil. Soil biological fertility showed a slow but significant response to compost addition as from the second year of treatment microbial growth and enzyme activity were increased compared to those of the inorganic fertilization, with special regard to enzymes involved in P cycle. A shift in the soil microbial community structure was also observed in compost-treated soil, with higher presence of copiotrophic bacteria, indicators of soil quality, and phosphorus solubilizing bacteria. A decrease of pathogenic fungal strains was also observed. Organic fertilization increased plant nutrient uptake and vegetative growth compared to those observed in chemically fertilized vines. A trend toward increased yield and improvements for some grape quality parameters such as acidity and pH were observed in the first year of production. These results provide evidence that compost can boost soil fertility restoration in vineyard disturbed by land terracing, allowing for agronomic performances comparable or even improved than those of chemically fertilized vines.

Comparative analysis of physical, morphological, and mechanical characteristics of eggs from three pheasant subspecies

The profitability of pheasants breeding is influenced by many factors, but eggs quality is considered as the backbone for successful pheasant breeding. The objective of this study was to determine and compare various quality characteristics (physical, morphological, and mechanical) of eggs from three pheasant subspecies: common pheasant (Phasianus colchicus colchicus), Mongolian pheasant (Phasianus colchicus mongolicus), and black pheasant (Phasianus colchicus vs. tenebrosus). A total sample of 180 eggs (60 eggs of each pheasant subspecies) was collected from pheasant hens kept in aviaries in their first year of production (43-47 wk of age). The average weight and volume of eggs from common pheasants was significantly lower (P ˂ 0.05) than those from Mongolian and black pheasants. No significant differences between three pheasant subspecies were observed in albumen and yolk weight and percentage, while egg shell weight and percentage were significantly higher (P < 0.01) at eggs from black pheasants. In comparison to eggs from Mongolian and common pheasants, eggs from black pheasants had the thickest shell and the highest shell strength and required highest force to egg breaking. The values of breaking force and other mechanical characteristics depend on the direction of the loading force during egg compression. The data obtained by evaluating certain characteristics of egg quality can be useful to breeders when choosing a pheasant subspecies, as well as for choosing quality eggs for hatching and their storage.

Magnetic Separation and Enrichment of Fe–Ti Oxides from Iron Titaniferous Beach Sands: Process Design Applied to Coastal Ecuador

Iron titaniferous sands, also called black sands, are a source of various magnetic minerals, such as iron and titanium (Fe–Ti) oxides, with countless scientific and industrial applications. Ecuador is deemed a geo-diverse country that contains deposits of black sands in the Andean and coastal regions; therefore, the industrialization of these magnetic sands might be of high interest. This study presents a preliminary industrial design for the magnetic separation process of Fe–Ti oxides from iron titaniferous Ecuadorian beach sands. Four stages are considered for the process, involving collecting, drying, screening, and magnetic separation. This proposal returns the large particles (&gt;150 μm) and the non-magnetic fraction to the original place, generating a minimum environmental impact with the support of natural marine and coastal processes. The process design criteria are based on engineering guidelines, sampling, and characterization of eleven black sand samples. Using conventional techniques, the water content, granulometric distribution, particle size, and semi-quantitative Fe–Ti oxide concentration were determined for the different sand samples. It is estimated that Fe–Ti oxide production may reach 5.835 metric tons per day (5.835 mtpd) with a magnetic content of 97.50%, starting from 100 mtpd of black sands. Based on an economic analysis (Class V), a net profit of USD 835,875.63 is expected during the first year of production. Thus, the magnetic separation and enrichment of Fe–Ti oxides from iron titaniferous coastal sands exploitation should allow the commercial valorization of these resources in an eco-friendly way, i.e., with economic benefits and minimization of environmental impact in the source area.

Bacterial community development and diversity during the first year of production in a new salmon processing plant

The bacterial diversity and load on equipment in food processing facilities is constantly influenced by raw material, water, air, and staff. Despite regular cleaning and disinfection, some bacteria may persist and thereby potentially compromise food quality and safety. Little is known about how bacterial communities in a new food processing facility gradually establish themselves.Here, the development of bacterial communities in a newly opened salmon processing plant was studied from the first day and during the first year of operation. To focus on the persisting bacterial communities, surface sampling was done on strategical sampling points after cleaning and disinfection. To study the diversity dynamics, isolates from selected sampling and time points were classified by Oxford Nanopore Technology-based rep-PCR amplicon sequencing (ON-rep-seq) supplemented by 16S rRNA gene or rpoD gene sequencing (for Pseudomonas). An overall increase in bacterial numbers was only observed for food-contact surfaces in the slaughter department, but not in filleting department, on non-food contact surfaces or on the fish. Changes in temporal and spatial diversity and community composition were observed and our approach revealed highly point-specific bacterial communities.

From Seismic Pre-Stack Elastic Attributes to Rock Properties. A Case Study in the Permian Basin, Onshore USA

The Permian Basin contains significant oil and gas-bearing shale deposits. Extending over 55 counties in West Texas and southeast New Mexico, it covers a vast region. It is the largest contributor to the oil shale boom in the US and in February 2022 accounted for more than 40% of US oil, Figure 1 (Federal Reserve Bank of Dallas 2022). Figure 2 displays the increase in produced oil from this basin from 2018 to 2022, Chevron News Room 2022. During the first years of production from these tight shales, seismic data weren’t considered to be essential for locating and drilling high-producing wells. However, the value of seismic data are now recognized and extensively used to design and execute lateral drilling programmes into the most prolific shale units. The shale deposits are widespread but highly heterogeneous in composition. Specifically notable is the lateral variability of Total Organic Content (TOC) and rock properties, such as porosity within the formations. In addition to varying shale properties, carbonate units were deposited simultaneously and are difficult to distinguish when only using reflectivity. Traditionally, the sonic and density values were inputted into supervised and non-supervised neural network applications to estimate rock properties. However, it is difficult to calculate density from conventional seismic data, and the results are typically questionable and have a high uncertainty element. To calculate density from seismic data, we need long offsets that are usable; most of the time, these data are not available (Aki, K., 1980). This study showcases a unique approach and its application using the LambdaRho-MuRho cross plot to estimate rock properties. The LambdaRho and MuRho values are derived from pre-stack inversions and are correlated to existing well data over the zone of interest. The results indicate that this is a more elegant and valid methodology, especially since it seems to produce a better, more accurate distinction between shale and carbonate domains.

Formation pressure distribution and productivity prediction of fractured horizontal wells in stress sensitive reservoirs

Aiming at the problems of formation pressure distribution and productivity prediction after Horizontal Well Volume Fracturing in stress sensitive reservoirs, the methods of dynamic permeability and dynamic threshold pressure gradient are used to deal with the influence of stress sensitivity, a numerical simulation method of oil-water two-phase flow based on finite element method is established. History matching is performed on the basis of the prediction of formation pressure distribution after horizontal well volume fracturing of, which ensures high matching accuracy. Taking the ultra-low permeability sandy glutenite reservoir of Baikouquan Formation in M18 area of Aihu Oilfield as research object, the influence law of formation pressure level on productivity and stress sensitivity on formation pressure distribution is studied. Analysis of the calculation results shows that: the influence of formation pressure level on well productivity is mainly in the first year of production, and the effect of energy increasing by volume fracturing is clarified. Stress sensitivity mainly affects the middle and later stage of production. With the increase of sensitivity, the permeability loss of the formation tends to be concentrated in the low-pressure area near the artificial fracture, forming an isolation zone with high flow resistance, which make the development effect of far well zone worse.

Retracted: CO2 Sequestration and Enhanced Shale Gas Recovery by CO2 Injection: Numerical Simulation Method

In previous decades, shale gas production has been given special attention as a clean source of energy. Technological advancements in multi-well especially horizontal drilling and hydraulic fracturing, have raised more research on how to produce shale gas commercially while studying its challenges. CH4 gas production by using CO2 injection is a combination of several parameters, including both fracking and geologic parameters. This paper investigated the influence of aligned and staggered multiwell placement patterns to enhance CH4 gas recovery and CO2 sequestration. A three-dimensional reservoir model was built and simulated, and the influence of reservoir and fracking parameters was analyzed. The results revealed that the staggered well pattern is the best pattern for CH4 gas recovery during continuous injection, with a 37% increase of recovery with late CO2 breakthrough, compared with the aligned well pattern, which had 31% increase recovery, associated with early CO2 breakthrough. In terms of CO2 gas storage, the aligned well pattern had a significant amount of CO2 storage during continuous injection and huff and puff injection by storing 4% more carbon dioxide during continuous injection and 7% more during huff and puff injection than that in the staggered well pattern. Different injection timings of 1, 2, and 3 years, and injection cycles of one, three, and five cycles were analyzed during huff and puff injection. The results showed that five cycles of injection had the highest methane gas recovery, 23% and 21%, in aligned and staggered well patterns, respectively. Furthermore, the influence of injection start time also was analyzed, and results showed that injection after 10 years of production produced higher methane gas recovery and CO2 storage in both aligned and staggered well patterns, followed by injection after 5 years of production, after 3 years of production, and during the first year of production. Sensitivity analysis revealed that horizontal matrix permeability, vertical matrix permeability, initial reservoir pressure, reservoir temperature, injection pressure, injection rate, fracture porosity, and fracture spacing played a vital role in both methane gas recovery and carbon dioxide gas storage in both well patterns. In addition, results showed that methane recovered during continuous injection is higher than during huff and puff injection in both aligned and staggered well patterns. Results obtained from this paper can help to improve shale gas production in multiwell placements, and save time and cost. This paper should motivate more research into the mitigation of global warming through CO2 geosequestration.

Is a viable hemp industry in Florida’s future?

Disease and foreign competition have made many growers question the viability of traditional commodity crops such as tomatoes, citrus, and avocados. Industrial hemp appears to be an attractive alternative, as the 2018 Farm Bill permitted its production. Florida has followed several other states in approving permits in 2020 to allow production of industrial hemp. Markets for industrial hemp products were promising in the first years of production, but market prices started to decline dramatically in 2020 with many growers unable to sell all their product. In this publication, we examine the hemp value chain with a focus on opportunities in the Florida market. Better coordination between regulators, processors, financial institutions, research and Extension services, and the retail sector to build confidence, harmonize policies, and lower transaction costs would help the industry flourish and ensure growers, consumers, and hemp-related enterprises can benefit from this emerging market.

Intercropping Alfalfa into Silage Maize Can Be More Profitable Than Maize Silage Followed by Spring-Seeded Alfalfa

Intercropping of silage maize (Zea mays L.) and alfalfa (Medicago sativa L.) is not a common practice because alfalfa generally reduces maize grain and biomass yield. The objective of this research was to evaluate the productivity and profitability of silage maize–alfalfa intercropping, with a goal to establish alfalfa and increase alfalfa productivity in the first year of production. The experiment was conducted in Fargo and Prosper, ND, USA, in 2014–2017. The design was a randomized complete block with four replicates and a split-plot arrangement. The main plot had two maize row-spacing treatments (RS), 61 and 76 cm, respectively. Treatments in the subplot were: (1) maize monoculture, (2) maize intercropped with alfalfa, (3) maize intercropped with alfalfa + prohexadione-calcium (PHX), and (4) spring-seeded alfalfa in the following year (simulating a maize–spring-seeded alfalfa crop sequence). Both alfalfa and maize were seeded the same day in May of 2014 at both locations. Prohexadione-calcium, a growth regulator to reduce internode length and avoid etiolation of alfalfa seedlings, did not improve alfalfa plant survival. Averaged across locations, RS did not have an effect on silage maize yield and alfalfa forage yield. Alfalfa established in intercropping with maize had almost double the forage yield in the following year compared with spring-seeded alfalfa following a crop of silage maize. Considering a two-year system, alfalfa intercropped with maize had higher net returns than a silage-maize followed by a spring-seeded alfalfa sequence. This system has the potential to get more growers to have alfalfa in the rotation skipping the typical low forage yield of alfalfa in the establishment year.

In situ characterization of benthic fluxes and denitrification efficiency in a newly re-established mussel farm

Mussel farming has been proposed as a mechanism to mitigate eutrophication in coastal waters. However, localizing the intensive filtration of organic matter by mussels can cause a concomitant enrichment of organic matter in sediments below farms, which may influence biogeochemical processes and fates of nutrients in the system. In the context of mitigating eutrophication, it is important to quantify sedimentary changes induced at early life stages of mussel farms. Accordingly, this study investigated how a newly re-established mussel farm affected sedimentation rates, sediment characteristics, sediment-water solute fluxes and nitrate (NO3−) reduction rates (measured in situ) during the first year of production. Sedimentation rates were enhanced at the farm relative to a reference station, and both organic and inorganic carbon accumulated in the sediment with time. Increased organic matter input likely drove the slightly elevated sedimentary effluxes of ammonium (NH4+) and dissolved inorganic phosphorus (DIP) in the farm. Denitrification was the main NO3− reduction process, however, there was a relative increase in the remobilization of bioavailable nitrogen underneath the farm as dissimilatory nitrate reduction to ammonium (DNRA) rates were enhanced by >200% and the denitrification efficiency was 49% lower compared to the reference station. The sedimentary methane (CH4) release tended to be higher at the farm, but fluxes were not significantly different from reference conditions. Low sedimentary pigment concentrations indicated a reduced presence of benthic microalgae at the farm, which likely influenced sediment-water solute fluxes. Over the production cycle, the release of dissolved inorganic nitrogen (DIN) and DIP underneath the farm were respectively 426% and 510% relative to reference conditions. Impacts of the mussel farm were thus measurable already during the first year of establishment. These immediate changes to the sediment biogeochemistry, as well as long-term effects, should be considered when estimating the environmental impact of mussel aquaculture.

Can it be all more simple? Manufacturing aflatoxin biocontrol products using dry spores of atoxigenic isolates of Aspergillus flavus as active ingredients.

SummaryAflatoxin contamination of staple crops, commonly occurring in warm areas, negatively impacts human and animal health, and hampers trade and economic development. The fungus Aspergillus flavus is the major aflatoxin producer. However, not all A. flavus genotypes produce aflatoxins. Effective aflatoxin control is achieved using biocontrol products containing spores of atoxigenic A. flavus. In Africa, various biocontrol products under the tradename Aflasafe are available. Private and public sector licensees manufacture Aflasafe using spores freshly produced in laboratories adjacent to their factories. BAMTAARE, the licensee in Senegal, had difficulties to obtain laboratory equipment during its first year of production. To overcome this, a process was developed in Ibadan, Nigeria, for producing high‐quality dry spores. Viability and stability of the dry spores were tested and conformed to set standards. In 2019, BAMTAARE manufactured Aflasafe SN01 using dry spores produced in Ibadan and sent via courier and 19 000 ha of groundnut and maize in Senegal and The Gambia were treated. Biocontrol manufactured with dry spores was as effective as biocontrol manufactured with freshly produced spores. Treated crops contained safe and significantly (P < 0.05) less aflatoxin than untreated crops. The dry spore innovation will make biocontrol manufacturing cost‐efficient in several African countries.

Production Data Analysis of Hydraulically Fractured Horizontal Wells from Different Shale Formations

A comprehensive overview and analysis of the productivity of 1216 recently abandoned multi-stage hydraulically fractured horizontal wells from five shale formations in the United States (US) is presented in this study. In this study, two decline curve analysis (DCA) methods were used to match actual production history data using least-squares fitting to find the best fit production parameters to reliably forecast production. The production history matching conducted resulted in very accurate matches (correlation coefficient of 0.99) between actual production data and the two DCA methods (Arps hyperbolic decline and stretched exponential production decline (SEPD) models). Using the outcomes from production history matching, universal averages of decline parameters for Arps hyperbolic decline and SEPD models were developed for each of the five formations. Furthermore, hindcasting was performed by matching a portion of the known production history and comparing the remaining portion of the known production history to the forecast. The Arps hyperbolic decline and SEPD methods were used to match production using only limited early production data (three months, six months, one year and two years). The main goals for fitting the DCA model to early production data was to estimate the optimum decline parameters that are then used to forecast production and estimate ultimate recovery. Production history matching using limited early production periods produced accurate production forecasts using as few as six months of production history (correlation coefficients between 0.85 and 0.94 using Arps hyperbolic decline). The main outcome of this study was a production analysis conducted on the production data of more than 1000 wells from five different shale formations to present the expected production behaviors of similar wells. Different production key performance indicators (KPIs) such as average well life, cumulative production volumes at different periods, average drop in production rate within the first year of production, average time to reach maximum flow rate, and the maximum flow rate were measured on all the wells from the five formations to provide an overview of the production performance of each formation.

Predictions on the water content in natural gas and water distribution in the China-Russia eastern gas pipeline

In the process of natural gas transportation, the existence of free water is a disturbing problem. This paper studies the calculation model of the natural gas water content of the China-Russia eastern gas pipeline and the amount and distribution of fluid accumulation in the China-Russia eastern gas pipeline commissioning stage. By comparing the calculation, Li correlation with the Keenan-Keyes model is a suitable model for calculating the natural gas water content of the China-Russia eastern gas pipeline. According to the model and software calculation, under the winter conditions in the first year of production of the China-Russia eastern gas pipeline, the total water accumulation in the pipeline increases with the increase of water content. The water produced in the pipeline can reach 255 × 103 m3 in the case of saturated water content in the first year of production. The water accumulation in the pipeline is mainly distributed in the ascending part of the low-lying pipe section. Where the height difference of the pipeline is greater, the water accumulation is more serious. In the pipeline section with a mileage of 53km - 134km, the water accumulation was the most serious, and the liquid holdup was as high as 0.66.