Results Of Long-term Field Experiments Research Articles

Methodology for forming a digital farming management system

The paper presents methodological approaches for the creation of a digital farming management system (DFMS). A convergent approach, based on cognitive (conceptual) analysis methods, is employed in the research and applied to the formation of adaptive landscape farming systems. The fundamental principles of organizing DFMS include crop and environmental monitoring (in situ, remote sensing); the formation of farming system archetypes based on the analysis of long-term field experiments; spatial object modeling and land typology using GIS; planning and support for agrotechnologies to adapt to natural and economic conditions; modeling ecosystem services and biodiversity; assessing the impact on the sustainability and economics of crop production. The system is implemented using geoinformation models in a specific geographic coordinate. DFMS involves conducting a "inventory" of natural and production resources, as well as identifying limits of climatic, soil, and agrolandscape parameters at different levels of land use intensity. At each stage of organizing system blocks, methods of intelligent data analysis and machine learning are used, with the core of the system relying on the use of knowledge bases and logical rules of the subject area. A key element of the system is the scaling of the results of long-term field experiments and accumulated knowledge in different management areas based on the parameterization of the multi-level variability of farming systems and the formation of their archetypes. The practical implementation of the main provisions of DFMS allows approaching the solution of key issues related to reducing the level of uncertainty and associated risks in agriculture. This is achieved through scientifically justified organization of rational land use, increasing the resilience of crop production in different land use conditions, and providing information support to rural producers.

Local biogeochemical cycles of trace elements in agroecosystems of Western Siberia

The article presents the results of long-term field experiments (2005-2022) to study the distribution and migration of trace elements in the soil-plant-animal system on the example of agrocenoses of the southern forest-steppe of Western Siberia. A biogeochemical assessment of the content of trace elements (Pb, Cu, Zn, Ni, Cd, Cr, Se) in trophic chains under certain agroecological conditions is given. The analysis of geochemical factors affecting the accumulation of trace elements in various types of soils and plants growing on them has been carried out. Normative quantitative characteristics of the action of trace elements on the chemical composition of the soil, productivity and quality of plants of grain, fodder and vegetable crops have been established. The relationship of macro- and microelements when they enter plants is shown, depending on the level and ratio of chemical elements in the soil, the physiological needs of the plant organism at different stages of ontogenesis.The parameters of the intake of trace elements into the body of animals with plant food under the conditions of model experiments have been established. Structural and functional changes in animal organs during feeding with crop products grown with different content of trace elements are analyzed.

СЕМЕННАЯ ПРОДУКТИВНОСТЬ И ЖИЗНЕСПОСОБНОСТЬ СЕМЯН СОРНЫХ РАСТЕНИЙ В РАЗЛИЧНЫХ ТИПАХ ПОЧВ

The results of longterm field experiments on two types of soils (chernozem and kastano-zems) are presented. The indicators of average seed productivity of more than 50 species of weeds growing in these soils are presented. The duration of the viability of seeds planted in a 0–30 cm soil layer, the quality of seeds during their layer-by-layer placement in the soil, on its surface and during storage in a dry warehouse is indicated. It was revealed that early spring and wintering weeds in chernozem soils had the highest seed productivity (more than 50 thousand seeds per plant). It was established that these seeds remained viable in the soil from 3 to 6 years (23 species), more than 6 years (20 species), and less than 3 years (only 3 species). In kastanozems soils, the seed productivity of most weeds decreased by 11–26% compared to chernozems. The loss of seed viability occurred more intensively in kastanozems soils than in chernozem soils. It was established that the lowest viability of seeds on both types of soils was observed during their longterm stay on the soil surface: after 5 years it did not exceed 12–15%, and after 10 years – 2–3%, while in the 0–10 cm layer of chernozem soils, it reached 36 and 18%, respectively, and in kastanozems soils it decreased more strongly and did not exceed 26 and 10%. In the lower soil layers, 10–20 and 20–30 cm, higher viability of weed seeds remained in kastanozems soils.

Introduction of ornamental herbaceous plants native to the Eurasian steppes in Laboratory of Ornamental Plants, at Main Botanical Garden of Russian Academy of Science

The steppes of Eurasia are promising donors for the introduction of ornamental plants. But when introduced to wetter regions, a number of species face the problem of their low ex situ stability. The purpose of the present work is to evaluate the results of the introduction of steppe species of ornamental herbaceous perennials in the Laboratory of ornamental plants (LOP) GBS RAS. The objects of the study are 84 species belonging to 53 genus from 23 families. In the introduction studies, two classical methods were used: the ecological-phytocenotic method and the method of generic complexes. To maintain the culture of some collections or their components, the method of ecotrons is also used. The analysis of the composition of the introduced species included in the modern collection fund of the LDR of the GBS RAS suggests that the most promising are groups of species with a wide response rate, which, in addition to steppe habitats, are confined to more remote ones. According to the results of long-term field experiments, the most stable species under long-term cultivation were identified. It is established that for a number of steppe species, long-term maintenance in culture is possible only with the use of a specially created substrate. Ex situ conservation of dry steppe species proper is extremely difficult and little practical. In MBG RAS Salvia stepposa Des.-Shost., Linum perenne L., Verbascum phoeniceum L., Dracocephalum ruyschiana L., Eremurus fuscus (O. Fedtsch.) Vved., Iris pumila L., I. scariosa Willd. ex Link, I. furcata Bieb., I. timofejewii Woronow, I. lutescens Lam. they were short-lived in the culture.

Перспективы химической мелиорации кислых почв

The presented materials are prepared on the basis of the results of long-term field experiments of domestic and foreign research institutions, results of agrochemical monitoring in the system of agrochemical service of the Russian Federation in various soil and climatic zones of Russia. The materials substantiate the importance and role of lime acidic soils, presented analysis of the state and dynamics of acidity of soils of agricultural land, the features of the use of different forms of limecontaining materials. The main functions of soil lime are indicated and the consequences in case of weakening of soil acidity are predicted. It has been established that the effect of the reclamation on the acidity of the soil is divided into two periods. The maximum displacement of pHKCl is observed 3…5 years after the introduction of the reclamation. The prevailing doses of lime in the materials given were doses of Saso3 4…6 t/ha, i.e. the most commonly used in the Non-Black Earth area. The quantitative parameters of changes in the level of acidity of the environment with the systematic use of physiologically acidic mineral fertilizers, especially nitrogen and potassium, which have an increasing effect on calcium loss from the soil. The growing negative effect of nitrogen-potassium fertilizers on the physical and chemical properties of the soil can lead first to their partial, and then to complete inefficiency on turf-sub-golden soils. The quantitative parameters of changes in the level of soil response in flood conditions during rice cultivation have been established. The results of the effect of different doses of lime on crop yields are presented. It is noted that soil lime is the main environmental measure to ensure the stabilization of the environmental safety of agro-censors and obtain products that meet sanitary standards. The need to restore the practice of lime in the right volumes in the near future is emphasized.

База данных биологических показателей управления продуктивностью агроценозов бобовых культур

Experimental data gained through research requires systematization and interpretation of the effectiveness of applicable objects, methods and agricultural technologies. This data is of scientific and practical value for proper decision-making in agricultural practice. The purpose of the research is twofold: 1) to develop a structured database based on the results of long-term field experiments using various plant-microbial symbioses in legumes agrocenoses under soil and climatic conditions of the Crimea; 2) to generalize information to search for the possibility of biological control of plant productivity. The database has the minimum software requirements: Microsoft Office suite for Microsoft Windows operating systems (XP or higher OS) and software package for statistical analysis Statistica_10. Data collection, sorting and systematization, as well as matrix writing was carried out in Microsoft Excel; database structure development and design – using Microsoft Visual Basic for Application (VBA); data analysis and processing, as well as agrocenosis productivity modelling, were carried out with the help of Statistica (StatSoft) version 10. The database size is 8 MB. It has three structured VBA blocks: 1) biological activity of the soil, 2) physiological and biochemical status, productivity of plants and 3) matrices of indicators of biological activity of the soil and plant biology. Information on the structural and functional organization of the soil microbiocenosis, enzymatic activity and soil respiration, symbiotic efficiency, intensity and direction of microbiological and biochemical processes in the rhizosphere of legumes, as well as their physiological status, productivity and seed quality included sequentially. The Database is implemented on 23 electronic sheets in Microsoft Excel, integrates and interacts with the Statistica_10. The Database allows searching for interactive links in the system “microorganisms–plants–soil”, modelling the productivity of agrocenoses, identifying plant-microbial systems with the active interface when using polyfunctional microbial preparations in the technology of growing legumes under soil and climatic conditions of the Crimea. With the help of the database, we found that the use of polyfunctional microbial preparations causes different potential in the system “microorganisms–plants–soil”. Bacterization of plants with microbial preparations has 1.8 times factorial effect more on the physiology and productivity of legumes (76 %) compared to a factorial effect on the biological activity of the soil in the agrocenosis (42 %). The potential of the interaction of the cyanorhizobial consortium with legumes was revealed. It had a minimal total factor difference (29 %) between the physiological and biochemical state, productivity of legumes and indicators of biological activity of soil compared to ‘Rhizobofit’ (36 %), ‘Rhizobofit’, ‘Phosphoenterin’, ‘Biopolycid’ (33 %), ‘Rhizobofit’ and arbuscular mycorrhizal fungi (39 %).

Influence of Fertilizer Systems on Soil Organic Carbon Content and Crop Yield: Results of Long-Term Field Experiments at the Geographical Network of Research Stations in Russia

The results of long-term experiments (LTEs) performed at the Geographical Network of experimental stations encompassing major soil types in Russia (soddy-podzolic (Retisols, Luvisols, and Podzols); gray forest (Luvic Greyzemic Phaeozems); leached, typical, and southern chernozems (Chernozems); chestnut soils (Kastanozems); meadow brown soils (Albic Stagnic Luvisols); and meadow chernozem-like soils (Luvic Greyzemic Stagnic Phaeozems)) within the entire country (from the north to the south of the European part of Russia, Siberia, and the south of the Far East region (Amur oblast, Khabarovsk, and Primorskii regions)) are summarized. Most of the stationary LTEs were lasting 20–45 years; ten LTEs lasted from 50 to 81 years. It was found that the organomineral fertilizer system (OMFS) exceeded the mineral fertilizer system (MFS) in its effect on the yield by 1–40% in 18 experiments, while the MFS was more efficient than the OMFS by 2–3% in only three LTEs. For the same soil type, the differences in Corg content between unfertilized trials reach 0.56–1.55% for soddy-podzolic soils and 1.58–3.93% for chernozems. Differences in soil Corg content between the unfertilized and OMFS (manure + NPK) trials were less than 10% in four LTEs, 11–20% in six LTEs, and >20% in ten LTEs; the average difference reached 0.27% of Corg. The levels of minimum (Cmin) and optimum (Copt) organic carbon content have been determined with due account for the soil types, soil texture classes, and the applied fertilizer system. They can be used as reference values for the studied soils.

Numerical simulation of polarization characteristics of an echo signal in the process of ground-based cloud sensing in the terahertz range

Results of numerical statistical simulation of an experiment on ground-based sensing of the cloud layer by linearly polarized terahertz range radiation at several wavelengths from the transmission windows of the atmosphere are presented. The models of the scattering layer involve liquid droplet size distribution functions pooled by results of long-term field experiments in middle latitudes of the Earth, as well as distribution functions obtained in flight measurements near the coast of Great Britain. The models of the scattering medium take into account the vertical stratification of water vapor in the atmosphere and the difference in the microstructure of the cloud layer near its top and bottom.

Territorial and temporal extension of the results of long-term field experiments

Agronomic experiments resemble dialogues with the plant, the soil, and the studied medium in general. The results of long-term field experiments are only valid for a given territorial unit and a given time interval, so if they are to be used by the agronomic advisory service as an exact scientific basis for a larger area and for a longer period, the measured point and minute information must be extended and validated in space and time. The paper emphasizes the unavoidable necessity of this extension, summarizes the limitations and difficulties, introduces various alternative solutions and discusses their practical applicability.

Importance of long-term experiments in studying the effects of climate change

Nowadays, studying the impact of climate change on agricultural crops is of great importance in national and international projects. Research on the effects of climate change on agricultural cultivars is supported by crop growth models. Simulations provide facilities for the low cost investigation of the effects of many factors, both independently of each other and in combination. These models require parameterisation and testing, which can be done using data measurements. In order to test the correctness of the simulations of meteorological and nutrient supply effects, it is necessary to use the results of long-term field experiments with many replicates.In the present study, the Ceres Wheat and AFRCWHEAT2 winter wheat crop growth models were tested, utilizing the data of a five-year sowing date experiment and the relevant meteorological data. An analysis was made of whether changes in the sowing date were able to influence or eliminate the negative effects of the changing climate. It was found that choosing the optimum sowing date could be the key to adapting to changing conditions.

Effects of Radioactive Contamination on Plant Populations: a Case of Low Doses and Multipollutant Exposure

An assessment of the state of plant and animal populations inhabiting polluted territories and the analysis of mechanisms of their adaptation to adverse environmental conditions undoubtedly has general biological importance. Consequently, studies that examine biological effects on non-human biota in natural settings provide a unique opportunity for obtaining information about the potential biological hazard associated with radioactive contamination. Nevertheless, up to now there is a distinct lack of quantitative data on the real long-term biological consequences of chronic radiation exposure lasting a long period of time. Actually, few studies exist that are directly relevant to understanding the responses of plant and animal populations to radionuclides in their natural environments. The results of long-term field experiments in the 30-km Chernobyl NPP zone, in the vicinity of the radioactive wastes storage facility (Leningrad Region), at radium production industry storage cell territory (the Komi Republic), in the Bryansk Region affected by the Chernobyl accident, and in Semipalatinsk Test Site, Kazakhstan that have been carried out in our laboratory on different species of wild and agricultural plants are discussed. Although radionuclides cause primary damage at the molecular level, there are emergent effects at the level of populations, non-predictable solely from the knowledge of elementary mechanisms of the pollutants’ influence. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic disturbances and genetic diversity. Man-made pollution may influence an evolution of exposed populations through a contaminant-induced selection process. Radioactive contamination of the plants environment activates genetic mechanisms, changing a population’s resistance to exposure. However, in different radioecological situations, genetic adaptation to extreme edaphic conditions in plant populations could be achieved with different rates. These processes have a genetic basis; therefore, understanding changes at the genetic level should help in identifying more complex changes at higher levels.

Plants ecotoxicology. A case of low doses and multipollutant exposure

Results of laboratory, green-house and long-term field experiments carried out on different plant species (spring barley, Scots pine, bulb onion and others) to study ecotoxical effects of low doses and concentrations of such common environmental factors as acute and chronic γ-radiation, heavy metals, pesticides, artificial and heavy natural radionuclides, are presented. Special attention is paid to ecotoxic effects of chronic low dose exposures, synergistic and antagonistic effects of different factors' combined action. The results of long-term field experiments in the 30-km Chernobyl NPP zone and in the vicinity of a radioactive wastes storage facility are discussed. The data presented suggest that the further evolution of investigations in this field would issue in the development of a theoretical bases and practical procedures for environmental protection against radioactivity, taking into account the new experimentally confirmed facts about the presence of such essentially important singularities as the nonlinearity of a dose-effect relationship, radiation-induced genomic instability, phenomenon of radioadaptation, increased probability of synergetic and antagonistic effects of the combined action of different nature factors.

Airborne Nitrogen Input at Four Locations in the German State of Saxony-Anhalt - Measurements using the 15N-Based ITNI-System

The amount of atmospheric N deposition in Germany is actual rather uncertain. Estimates using standard methods indicate an N deposition of 30–35 kg N/ha × year. However, the results of long-term field experiments and newly by the ITNI (Integrated Total Nitrogen Input) system could prove a much higher N input of about 50–60 kg N/ha × year. The reason for this difference is that standard methods use wet-only or bulk collectors, which neglect gaseous and organic N deposition as well as direct N uptake by aerial plant parts. By contrast, the ITNI-system is able to measure the total atmospheric N input using the 15N isotope dilution method. The input of airborne N into a soil/plant system leads to a dilution of the abundance of a previously applied 15N tracer over a defined time period. The atmospheric N deposition can be calculated from this dilution. To estimate the actual N input in Central Germany, ITNI measurements were carried out from autumn 1998 to autumn 2000 at four locations in the German state of Saxony-Anhalt. Atmospheric N depositions between 45 and 75 kg N/ha × year were determined depending on the location. These results closely match to N balances of longterm field experiments. Furthermore, a relationship was found between N deposition and the plant species used as well as plant development.

Dynamic Model for the Effects of Soil P and Fertilizer P on Crop Growth, P Uptake and Soil P in Arable Cropping: Model Description

A mechanistic model is described for calculating the effects of starter fertilizer, granular fertilizer and 0.5M NaHCO3pH 8.5 extractable soil phosphate on plant growth and plant P concentration during the entire period of growth up to commercial harvest. For each day, the model calculates the increment in root growth and partitions it into segments between the regions of soil enriched with starter fertilizer, those enriched with granular fertilizer and the remainder of the soil. It calculates the maximum possible amount of P that can diffuse through soil to each root segment in each region. Using this information and the P concentration in the plant, total P uptake is calculated. The increment in plant weight and root growth is calculated from the current plant weight, plant P concentration and air temperature. Subroutines calculate daily soil water content, the extractable and non-extractable soil P, and diffusion coefficients in the P-depleted zones around each root segment and in the remainder of the soil. Model simulations and sensitivity analyses indicate that extractable soil P and starter fertilizer P can lead to higher crop yields than are achieved when granular fertilizers are incorporated in soil, in the usual way, immediately before sowing. They also indicate that in the long-term, levels of extractable soil P will move towards a level characteristic of the soil. These findings are in agreement with results of long-term field experiments that have been reported in the literature. All inputs to the model that have a substantial impact on P-response of a single crop are easy to obtain. They include standard soil properties, the maximum potential yield, and daily rainfall, mean air temperature and evaporation from an open water surface. The model runs interactively at: www.qpais.co.uk/phosmod/phos.htm

Response of Arctic ecosystems to climate change: results of long-term field experiments in Sweden and Alaska

Long-term field experiments at Abisko, Sweden, and Toolik Lake, Alaska, reveal both similarities and differences in response of contrasting Arctic ecosystems to changes in temperature, light, and nutrient availability. Five different ecosystems were manipulated for 5–15 years by increasing air temperature with greenhouses, by decreasing light with shading, and by increasing available N and P with fertilizers. The ecosystems at Abisko included evergreen-dominated heath and fellfield sites; at Toolik Lake they included wet sedge tundra, moist tussock tundra, and dry heath tundra. In all ecosystems, fertilizer treatment increased plant growth, production, and/or biomass. Plant responses to warming were smaller and occasionally nonsignificant, Responses to shading were generally nonsignificant after 3–6 years, although after 9 years the tussock tundra showed significant decreases in biomass. In general, the ecosystems at Abisko were less responsive to nutrients and more responsive to temperature than the ecosystems at Toolik Lake. Overall, though, the sites were quite similar in their responses to the perturbations, increasing our confidence in predictions of response to climate change over large areas based on small-area studies.

Response of Arctic ecosystems to climate change: results of long-term field experiments in Sweden and Alaska

Long-term field experiments at Abisko, Sweden, and Toolik Lake, Alaska, reveal both similarities and differences in response of contrasting Arctic ecosystems to changes in temperature, light, and nutrient availability. Five different ecosystems were manipulated for 5–15 years by increasing air temperature with greenhouses, by decreasing light with shading, and by increasing available N and P with fertilizers. The ecosystems at Abisko included evergreen-dominated heath and fellfield sites; at Toolik Lake they included wet sedge tundra, moist tussock tundra, and dry heath tundra. In all ecosystems, fertilizer treatment increased plant growth, production, and/or biomass. Plant responses to warming were smaller and occasionally nonsignificant, Responses to shading were generally nonsignificant after 3–6 years, although after 9 years the tussock tundra showed significant decreases in biomass. In general, the ecosystems at Abisko were less responsive to nutrients and more responsive to temperature than the ecosystems at Toolik Lake. Overall, though, the sites were quite similar in their responses to the perturbations, increasing our confidence in predictions of response to climate change over large areas based on small-area studies.

Description and evaluation of stress to mountain forest ecosystems results of long-term field experiments

Description and evaluation of stress to mountain forest ecosystems results of long-term field experiments

Multivariate Analyses of the Results of Long-term Field Experiments at the Shiga Agricultural Experiment Station (Part 1) : Pattern Analysis of Rice Yield

Multivariate Analyses of the Results of Long-term Field Experiments at the Shiga Agricultural Experiment Station (Part 1) : Pattern Analysis of Rice Yield