Protective forest plantations and treatment methods influence on agrophysical properties of chestnut soil and agricultural yield

The article presents the results of many years research on the complex effect of basic tillage and shelterbelts methods on the content of macroelements in the soil, the conditions of water supply and the formation of the spring barley yield on zonal light-chestnut soils.

PSXI-21 Soil emission of carbon dioxide and behavior of microorganisms in soils of Western Kazakhstan

Kazakhstan Western ecosystems are intensively used in agricultural production. Assessing greenhouse gas emissions from soils, especially CO2, is important. In the upper stages, microbiology, characteristics and condition of the soil change. Biological intensity indicators are soil respiration processes, numerous microbiocenoses species composition. Soil CO2 emissions were measured 5 times monthly during three years. The CO2 flow rate from soil surface is measured by a closed dynamic chamber method with Li-8100A field respirometer. Metagenomic soil testing used bacteria DNA, archaea, real-time PCR, 16SrRNA sequencing. The soil CO2 monthly dynamics fluxes varied among the lands, within the season. In 2020, the CO2 emissions soil peak noted in the pasture. There is a slight decline in summer with a decrease towards the cold season. Comparison between the CO2 flux pasture soils is less in virgin soil. The minimum CO2 flux was recorded in November - February; in the spring, the flux increases. The above CO2 emissions were recorded in summer. In soils, there is wide variety of microorganisms with opposite and incompatible properties for one habitat. The microbial communities structure identified at the family level. The taxonomic samples structure ominated by phylae - Actinobacteria, Proteobacteria, Chloroflexi, Acidobacteria, Gemmatimonadetes, Firmicutes, Actinobacteria. The spread explained by increased actinomycetes resistance characteristic to low moisture content with long dry period. For comparative evaluation microbial communities results comparing by cenoses of upper horizons with dark chestnut soil indicators. This violation caused microorganisms resistance to disturbing factors. On anthropogenically disturbed saline soils, the bacteria found were specific and resistant to critical conditions. CO2 emission in soil varied cenosis type. The CO2 intensity factors were precipitation deficit, high temperature. The profile microorganisms distribution corresponded to the soil horizons humus content. During summer soil drying, the deep soil horizons abundance occurred where moisture is retained.

Function and Characterization of Fungal Communities in Chestnut Soils (Castanea crenata) of Kansai Region, Japan

Chestnut (Castanea crenata) is an important fruit crop in Japan, grown under three cultivation systems in Kansai region, which succumb to fungal root disease pathogens. The fungal community in soils of chestnut in these cultivation systems were characterized along with the potential of soil bacterial species as biological control agent against these root-invading fungi. Bacteria from the chestnut soil rhizosphere were identified and their ability to suppress diseases in vitro was evaluated. Bacteria DAC17225011 and DAC17225014 showed 99% similarity to Bacillus aryabhattai and Pseudomonas frederiksbergensis, respectively, which could suppress the growth of Armilaria mellea and Phytophtora cambivora, respectively, in in vitro conditions. The assay in vivo indicated the positive effect of these bacteria on the reduction of disease infection spots in chestnut roots; however, no visible symptoms were detected aboveground. For microbial community analysis, chestnut soil was sampled from four locations (Wachi, Ayabe, Fukuchiyama and Sasayama) considering three management systems, conventional, organic and wild. The amplicon from the ITS region (The genomic library of the fungal detection in soils) was sequenced by Illumina MiSeq 250bp and used to analyze the fungal community in the sampled soil. Nectriaceae, which contains pathogenic fungi, was very common in all samples, but lower in wild areas. Ceratobasidiacea was also higher in conventional areas. For the symbiotic families, Hypocraceae and Russulaceae were typical in wild soils, whereas Amanitaceae was found in organic soils. The fungal community was clearly distinct in the wild system, differing from conventional and organic systems.

Agrogenic changes in the properties of dark chestnut virgin and arable soil with different use and irrigation

In the article, it was provided a comparative analysis of the ecosystem significance of soil characteristics transformed as a result of changes in the use conditions. At the three monitoring stationary sites in the Chaplinka district of the Kherson region, we studied the properties of dark chestnut soil (Haplic Kastanozem) on virgin lands (a biosphere reserve "Askania-Nova") and with more than a hundred years of use in agricultural production without irrigation and with a 50-year irrigation with water from the Kakhovsky trunk canal. Changes in the salt regime of the soil and the composition of exchangeable cations were established. In irrigation the total content of water-soluble salts up to 0.14-0.21% (toxic salts ‒ up to 0.06-0.15 %) was increased. The composition of salts was changed, their migration and accumulation in the lower soil layers. Under the influence of fresh water irrigation the process of dealkalinization in the dark chestnut soil took place. The involvement of virgin soil in agricultural use led to a decrease in the total content of humus and the transformation of its group composition. The content of humic acids (HA) was decreased. The content of fulvic acids (FA) was increased. The HA/FA ratio in the 0-10 cm layer changed from 2.6 (in virgin soil) to 1.6 in irrigated soil. The plowing and agricultural use of the dark chestnut soil led to a change in the state of the microbial cenosis. The number of microorganisms assimilating mineral and organic nitrogen, actinomycetes, oligotrophs, and eutrophs were increased. With irrigation the degree of transformation of the microbial cenosis increases. The indicator of biological degradation of irrigated dark chestnut soil was 4 %. This corresponds to a low level of degradation. A set of 10 indicators of the quality of the studied soil was proposed for calculating the level of its provision of ecosystem services (supplying and supporting). The algorithm and calculation results are presented. The soil of all monitoring sites of Markeev station is characterized by a high level of provision of ecosystem services. In virgin soil it was 8.3 points; in arable soil without irrigation it was 7.2, and with irrigation it was 7.5 points.

Environmental Behaviors of Procymidone in Different Types of Chinese Soil

Procymidone is a widely used fungicide in the prevention and treatment of fungal diseases on many crops in China. Part of the procymidone will enter the soil during the application process. Procymidone may exhibit environmental behavior diversity in different soils. Therefore, it is extremely important to clarify the environmental behavior of procymidone in soil for its environmental safety evaluation. Here, the degradation, adsorption, and mobility behaviors of procymidone in four typical types of Chinese soil were investigated for the first time. The half-lives of procymidone in the soils ranged from 14.3 d to 24.1 d. The degradation rates of procymidone in the soils were promoted by organic matter content, moisture content, and microorganisms. Furthermore, the degradation of procymidone on the soil surface was promoted by light. The desorption rates of procymidone in laterite soil, yellow brown soil, black soil, and chestnut soil were 27.52 ± 0.85%, 16.22 ± 0.78%, 13.67 ± 1.29%, and 7.62 ± 0.06%, respectively, which were contrary to the adsorption ability. The mobility order of procymidone in the soils was: laterite soil > yellow brown soil > black soil > chestnut soil, with the Rf values of 0.28, 0.22, 0.18, and 0.16, respectively. Three degradation products of procymidone were identified by liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry, and the degradation pathway of procymidone in the soil was speculated. The results will provide a theoretical basis for the removal of procymidone in the soil environment.

Effect of different basic tillage and fertilizer systems on corn grain yield, when irrigating in the south of Ukraine

The article presents the results of the research on soil bulk density and permeability as well as weediness of maize crops at the beginning and end of growing season on average for 2016-2019, applying different basic tillage and fertilizer systems. The goal of the research was to determine the effect of different methods and depth of basic tillage and fertilizers on agrophysical properties of soil and crop productivity in grain-row crop rotation when irrigating in the south of Ukraine. The objective of the research was to determine the effects of different methods and depths of basic tillage as well as fertilization on the agrophysical properties of dark chestnut soil and the productivity of corn in short crop rotation. During the experiment, field, quantitative-weight, visual, laboratory, calculation-comparative, mathematical-statistical methods and generally accepted in Ukraine methods and methodical recommendations were used. The research was conducted in the research fields of the Askanian SARS IIA NAAS of Ukraine. Based on the research results it was established that, both at the beginning and at the end of grooving season when applying the tillage up to 28-30 cm within the system of differentiated tillage bulk density was the smallest as 1,14 g/cm3 when using green manure and 1,19 g/cm3 without its use. When applying subsurface different depth tillage, bulk density increased up to 1,18 g/cm3 when using green manure and up to 1,26 g/cm3 without its use. Maximum bulk density of 1,28 g/cm3 was observed when no tillage applied without using green manure and 1,31 g/cm3 when using it that is by 12,3 and 10.1% higher compared to the reference area, respectively. The highest corn productivity was observed when applying subsurface different depth tillage, where the average values by the factor A were about 10,93 t/ha that is higher than those obtained in the reference area by 0,52 t/ha, or 5,0%. The use of zero tillage caused the obtaining of the lowest yield in the experiment as 8,71 t/ha that is less compared to the reference area by 1,7 t/ha, or 19,5%.