Comparative analysis of the profile variability of black soil water-physical properties when long-term applying plowing and no-till technologies use (the case of Panfily Research Station)

The results of actual research on profile variability of soil water-physical properties of undisturbed structure at the plots, where traditional plowing and no-till technology have been applied for 11 years, are given. The comparative research was conducted based on a stationary field experiment, which is carried out at Panfily Research Station of the National Scientific Center "Institute of Agriculture NAAS" when applying a system of laboratory diagnostics of water-physical properties created in the Institute of Water Problems and Land Reclamation of NAAS based on hydrophysical methods. The characteristics of main hydrophysical functions, namely moisture conductivity and water holding capacity, as well as hydrological constants - maximum hygroscopic moisture, withering point, minimal water holding capacity, maximum water holding capacity, specific surface area and active moisture range were obtained for three different depths. Based on the results of comparison, it was found that mesoporosity was more developed in the soil on the plots under plowing, while macroporosity was more developed on the no-till plots. The fundamental result is determining the inversion type of profile distribution of moisture conductivity in unsaturated soil. Thus, under on the no-till plots the highest values of moisture conductivity were observed in the deepest soil layer (0,70-0,85 m), decreasing to the soil surface, while on the plots under plowing the highest values of moisture conductivity were observed in cultivated soil layer (0,00-0,15 m), which naturally decreased in depth. The profile distribution of moisture conductivity on the no-till plots contributed to the infiltration supply of groundwater and capillary feeding of soil root layers from the deeper ones.

Profile distribution of available nutrients in a Vertisol and Inceptisol as influenced by irrigated and rainfed cotton crops

Current study was conducted in cotton growing belt of South Gujarat (Gujarat) i.e. in 11 talukas namely, Bharuch, Surat, Jhagadia, Jambusar, Amod, Vagra, Narmada, Tilakwada, Dediapada, Sagbara and Hansot. To fullfil the objectives of present research GPS based 22 nos. of pedons representative (11 irrigated and 11 rainfed situation) were dug out, studied and depth-wise samples (0-15, 15-30, 30-60, 60-90 and 90-120 cm) of above 11 talukas were collected. During course of study it was observed that available N, P2O5, K2O, S and DTPA-Fe and Zn in irrigated pedons, varied respectively from 111.4 to 303.2 kg ha-1 (low to medium), 17.1 to 63.3 kg ha-1 (low to high), 221.4 to 1164.8 kg ha-1 (medium to very high), 6.5 to 20.1 ppm (low to marginally high), 2.47 to 10.42 mg kg-1 (low to high) and 0.06 to 0.51 mg kg-1 (low to medium), while the corresponding values of rainfed pedons were 94.7 to 299.8 kg ha-1 (low), 10.8 to 57.1 kg ha-1 (low to marginally high), 160.7 to 1180.7 kg ha-1 (medium to very high), 6.2 to 18.7 ppm (low to medium), 1.63 to 10.27 mg kg-1 (low to high), and 0.08 to 0.48 mg kg-1 (low), respectively. Means of above available nutrients were found slightly higher under irrigated situations in comparison compared to those of rainfed situation.

Profile distribution of soil organic carbon fractions under different landforms in the Meghalaya plateau of India

Assessment of organic carbon fractions in soil provides the basis to ascertain vulnerability of an ecosystem to climate change. In the present study, we assessed SOC fractions in four pedons under contrasting landforms i.e., denudational low hill, upper plateau, lower plateau and valley in the Meghalaya plateau, India. Results indicated that soils of the studied pedons were acidic in nature, low in cation exchange capacity and base saturation. Further, surface (0-30 cm) soils were high in Walkley Black C (WBC) content (0.83-1.13%) in the studied pedons located under different landforms. The density of very labile carbon (VLC) fraction up to a depth of 150 cm was highest (49.22 Mg ha?1) in pedon 2 (P2) located in the upper plateau under shifting cultivation while that of less labile carbon (LLC) was highest (50.25 Mg ha?1) in pedon 4 (P4) in the valley under paddy cultivation. Higher densities of WBC and LLC in the valley (P4) as compared to other landforms in the study area indicate higher carbon sequestration potential of valley soil.

A Retroreflection Reduction Technique Based on the Wavefront Coded Imaging System

A novel anti-cat-eye effect imaging technique based on wavefront coding is proposed as a solution to the problem of previous anti-cat-eye effect imaging techniques where imaging quality was sacrificed to reduce the retroreflection from the photoelectric imaging equipment. With the application of the Fresnel–Kirchhoff diffraction theory, and the definition of generalized pupil function combining both phase modulation and defocus factors, the cat-eye echo formation of the wavefront coded imaging system is theoretically modeled. Based on the physical model, the diffracted spot profile distribution and the light intensity distribution on the observation plane are further simulated with the changes in the defocus parameter and the phase modulation coefficient. A verification test on the cat-eye laser echo power of the wavefront coded imaging system and that of the conventional imaging system at a 20 m distance are conducted, respectively. Simulations and experiment results show that compared with conventional imaging systems, the wavefront coding imaging system can reduce the retroreflection echo by two orders of magnitude while maintaining better imaging quality through defocusing.

Urbanization Affects Soil Microbiome Profile Distribution in the Russian Arctic Region

Urbanization in the Arctic results in considerable and still poorly known environmental consequences. The effect of urbanization on soil microbiome—an ecosystem component highly sensitive to anthropogenic disturbance—remains overlooked for the Arctic region. The research compared chemical and microbial properties of the natural Podzol soils and urban soils of Murmansk—the largest Arctic city. Particular attention was given to the profile distribution, which is almost completely ignored by most microbial studies. Soil microbiome was investigated by the quantitative indicators based on fluorescence microscopy (microbial biomass) and PCR real-time methods (amount of rRNA genes copies of archaea, bacteria, and fungi). The principal changes in urban soils’ properties compared to the natural references included a shift in pH and an increase in C and nutrients’ contents, especially remarkable for the subsoil. The numbers of rRNA genes copies of archaea, bacteria, and fungi in urban topsoils (106–1010, 109–1010, and 107–109, respectively) were lower than in Podzol; however, the opposite pattern was shown for the subsoil. Similarly, the total microbial biomass in urban topsoils (0.55–0.75 mg g−1) was lower compared to the 1.02 mg g−1 in Podzols, while urban subsoil microbial biomass was 2–2.5 times higher than in the natural conditions. Both for urban and natural soils and throughout the profiles, fungi were dominated by mycelium forms; however, the ratios of mycelium–spores were lower, and the amount of thin mycelium was higher in urban soils than in natural Podzols. Urbanization in the Arctic altered soil morphological and chemical properties and created a new niche for microbial development in urban subsoils; its contribution to biodiversity and nutrient cycling promises to become increasingly important under projected climate change.

Agroecological assessment of leached chernozems with different erosion level in conditions of the slope catena at the Central Chernozemic Region

Based on the complex investigation of agroecological parameters of leached chernozems with different erosion level in conditions of the slope catena at the Central Chernozemic Region (CChR), the features of agrogenic-erosive transformation of morphogenetic, chemical and physic-chemical properties of the investigated soils at the basic levels of their structural organization are shown – depending on the degree of their erosion. The influence of the processes of surface planar erosion and intra-soil lateral migration on the content and distribution of the most problematic heavy metals (HM) – Pb, Cd is considered. The analysis of the research results has shown that the development of erosion processes in conditions of the slope type of terrain characteristic for the CChR leads to a significant transformation of the main diagnostic indicators of the agroecological state of leached chernozems, primarily to the degradation of their morphogenetic and humus profile. The significant and slope-differentiated influence of erosion processes at the level of soil elementary particles, meso- and macro-levels of the soil structural organization has been established. The processes of erosion and lateral migration change the content and profile distribution of Cd and, especially, Pb in the studied leached chernozems. In the eroded soils, there is an increase in their mobility and accumulation in the subsoil. Keywords: LEACHED CHERNOZEMS, AGROECOLOGICAL STATE, EROSION, TRANSFORMATION AND DEGRADATION, HEAVY METALS, LEAD, CADMIUM

Features of the migration of heavy metals in the forest landscapes of the ’Kamennaya Steppe’

The article examines the influence of woody vegetation on the change in some soil properties. Numerous studies have confirmed the change in the water regime under forest belts. Such dynamics entails the transformation of morphological characteristics and the following basic soil properties: pH of the soil solution, carbon of organic compounds. The evolution of properties causes changes in the total content of heavy metals: nickel (Ni), lead (Pb), cadmium (Cd) and their exchange compounds. The features of the profile distribution of Ni, Pb and Cd in the chernozems of the forest belt have been studied. Elements were determined by atomic absorption spectrophotometry. Carbon of organic compounds - by titrimetric method, pH of soil solution - by potentiometric method. Wood species affect the profile distribution of heavy metals. Correlation analysis revealed a close relationship in the profile distribution of carbon of organic compounds, pH, Ni, Pb. Variational analysis of spatial heterogeneity showed the differences in the studied indicators between arable land and forest belt. A decrease in the coefficient of variation from the forest belt to arable land is noted. The phenomenon is explained by plowing, mixing the soil mass and leveling out spatial differences in the content of carbon of organic compounds, pH, heavy metals.