In Situ Non-Destructive Temporal Measurements of the Rhizosphere Microbiome ‘Hot-Spots’ Using Metaproteomics

Rhizosphere arguably embodies the most diverse microbial ecosystem on the planet, yet it is largely a functional ‘black box’ of belowground plant-microbiome interactions. The rhizosphere is the primary site of entry for subsurface injection of fixed carbon (C) into soil with impacts on local to global scale C biogeochemistry and ultimately Earth’s climate. While spatial organization of rhizosphere is central to its function, small scale and steep microbial and geochemical gradients within this dynamic region make it easily disrupted by sampling. The significant challenge presented by sampling blocks elucidation of discreet functions, drivers, and interactions within rhizosphere ecosystems. Here, we describe a non-destructive sampling method linked to metaproteomic analysis in order to measure temporal shifts in the microbial composition and function of rhizosphere. A robust, non-destructive method of sampling microbial hotspots within rhizosphere provides an unperturbed window into the elusive functional interactome of this system over time and space.

Modification of the unit for subsurface injection of organomineral fertilizers

Subsurface injection of liquid organomineral fertilizers provides activation of soil microflora, increased nutrient adsorption by plants, improved physical and agrochemical properties of soil, adsorption of harmful contaminants, pesticides and radioactive nuclides from soils. Subsurface injection of liquid fertilizers is usually carried out locally in planting or feeding seedlings, using sowing and planting units, plant nourishing cultivators, fertilizing systems, cultivators with feeding devices. (Research purpose) The research purpose is in increasing the efficiency of using liquid fertilizers, including organomineral fertilizers, by upgrading the developed technical means for their intra-soil application. (Materials and methods) The article presents the designed, manufactured and tested a technical tool for continuous intra-soil application of liquid organomineral fertilizers during pre-sowing soil treatment. Authors proposed the design of a combined device that includes a vertical milling cultivator, a system for injecting liquid organomineral fertilizers and a rolling drum and allows to carefully loosen the soil, grind root and crop residues, conduct a continuous intra-soil application of liquid organomineral fertilizers to a depth of 20 centimeters, as well as create a compacted seedbed. (Results and discussion) The authors identified a number of design flaws during the tests of the developed machine, and therefore decided to modernize some of them. Authors have upgraded the design of the cutter and coulter and changed the injection system of liquid fertilizers. (Summary) As a result of the modernization, authors have increased the charge productivity of the unit, improved the quality of soil treatment and increased the efficiency of fertilizer application by increasing the uniformity of their application.

Flowback verses first-flush: new information on the geochemistry of produced water from mandatory reporting

Unconventional oil and gas development uses the subsurface injection of large amounts of a variety of industrial chemicals, and there are concerns about the return of these chemical to the surface with water produced with oil and gas from stimulated wells.