Permanent Fields Research Articles

Trade-offs between grassland plant biodiversity and yields are heterogenous across Germany

Grasslands are key for food security and provide important ecosystem services. Intensive management, such as frequent mowing, increases productivity but decreases other ecosystem services as well as plant biodiversity. We here estimate large scale effects of mowing frequency on plant species richness and provide spatial assessments of yield-species richness trade-offs. We use a unique, multisource remote sensing-based dataset covering all permanent agricultural grassland fields across Germany (N = 1,313,073) over four years to estimate the causal impact of mowing frequency, as a proxy of grassland management intensity, on plant species richness. We identify spatially explicit and heterogeneous treatment effects using generalized random forests. We find that more frequent mowing significantly reduces plant species richness, but these effects vary by environmental and socioeconomic context. We quantify the trade-offs between species richness and yield due to changes in mowing frequency, finding an average cost of 126 euros per additional plant species, and demonstrate how spatial targeting can improve the cost-effectiveness of a hypothetical conservation policy, reducing this cost to 51 euros per species. Motivated by the 30 by 30 goal to protect 30% of terrestrial ecosystems by 2030, we further estimate opportunity cost of marginally extensifying 30% of German grasslands to be 131–181 million euros annually, depending on targeting priorities.

Tracking particle displacements in unbound aggregate layers of roadways

ABSTRACT Accelerated pavement tests were conducted on reduced-scale pavement sections under controlled environmental conditions using the model Mobile Load Simulator (MLS11). A unique monitoring system was developed as part of this study to evaluate the response of the pavement sections under rolling wheel loads. The performance of the sections with an increasing number of wheel passes was evaluated by measuring the surface rutting as well as the subsurface displacement of particles within the base layer. The sections were built in modular frames constructed above grade to facilitate access to the particles within the base layer from the sides of the frame. Surface rutting was measured intermittently using an in-house developed laser profilometer. A unique, cost-effective assembly of 30 linear position transducers was designed to continuously track the displacements of artificial particles within the base layer. The displacements, measured with the new system, were found to be particularly suitable to generate horizontal permanent displacement fields and strain fields. Overall, the new developments allowed comprehensive monitoring of the internal response of pavements subjected to wheel loading.

Modelling permanent magnet excited uniform fields with rational approximations

PurposeA novel method for modelling permanent magnets is investigated based on numerical approximations with rational functions. This study aims to introduce the AAA algorithm and other recently developed, cutting-edge mathematical tools, which provide outstandingly fast and accurate numerical computation of potentials and vector fields.Design/methodology/approachFirst, the AAA algorithm is briefly introduced along with its main variants and other advanced mathematical tools involved in the modelling. Then, the analysis of a circular Halbach array with a one-pole pair is carried out by means of the AAA-least squares method, focusing on vector potential and flux density in the bore and validating results by means of classic finite element software. Finally, the investigation is completed by a finite difference analysis.FindingsAAA methods for field analysis prove to be strikingly fast and accurate. Results are in excellent agreement with those provided by the finite element model, and the very good agreement with those from finite differences suggests future improvements. They are also easy programming; the MATLAB code is less than 200 lines. This indicates they can provide an effective tool for rapid analysis.Research limitations/implicationsAAA methods in magnetostatics are novel, but their extension to analogous physical problems seems straightforward. Being a meshless method, it is unlikely that local non-linearities can be considered. An aspect of particular interest, left for future research, is the capability of handling inhomogeneous domains, i.e. solving general interface problems.Originality/valueThe authors use cutting-edge mathematical tools for the modelling of complex physical objects in magnetostatics.

Hygienic regulation of electromagnetic fields in the Russian Federation: history and current state

The article presents in detail the history of the creation of hygienic normative documents regulating the industrial and non-industrial effects of electromagnetic fields in the Russian Federation. Systematic scientific research in the field of biological action and hygienic regulation of radio frequency electromagnetic fields in our country began at the Research Institute of Occupational Hygiene and Occupational Diseases, Academy of Medical Sciences of the USSR, where in 1952 specialists created the first laboratory of electromagnetic waves of radio frequencies in the country. In the future, a number of scientific institutions of hygienic, biomedical and physico-technical profile joined these studies. Scientists have scientifically substantiated the methodology of rationing hygienic factors. Over the past period, scientists have developed about 30 documents, including the maximum permissible level of electromagnetic fields. Currently, in the Russian Federation, the main current document establishing the maximum permissible level of permanent and variable electromagnetic fields in the workplace and for the public is SanPiN 1.2.3685-21 "Hygienic standards and requirements for ensuring the safety and(or) harmlessness of environmental factors for humans". The analysis made it possible to evaluate its advantages and identify disadvantages, as well as to outline promising areas of scientific research to improve existing and develop new maximum permissible levels of electromagnetic fields created by modern sources.
 Ethics. This study did not require the conclusion of the Ethics Committee.

Piezoelectric Relaxation in Piezoceramics in the Region of Weak Permanent Electric Fields

Piezoelectric Relaxation in Piezoceramics in the Region of Weak Permanent Electric Fields

The soil organic carbon: Clay ratio in North Devon, UK: Implications for marketing soil carbon as an asset class

AbstractBuilding up stocks of agricultural soil organic carbon (SOC) can improve soil conditions as well as contribute to climate change mitigation. As a metric, the ratio of SOC to clay offers a better predictor of soil condition than SOC alone, potentially providing a benchmark for ecosystem service payments. We determined SOC:clay ratios for 50 fields in the North Devon UNESCO World Biosphere Reserve using 30 cm soil cores (divided into 0–10 cm and 10–30 cm depth samples), with soil bulk density, soil moisture and land‐use history recorded for each field. All the arable soils exceeded the minimum desirable SOC:clay ratio threshold, and the ley grassland soils generally exceeded it but were inconsistent at 10–30 cm. Land use was the primary factor driving SOC:clay ratios at 0–10 cm, with permanent pasture fields having the highest ratios followed by ley grass and then arable fields. Approximately half of the fields sampled had potential for building up SOC stock at 10–30 cm. However, at this depth, the effect of land use is significantly reduced. Within‐field variability in SOC and clay was low (coefficient of variation was ~10%) at both 0–10 cm and 10–30 cm, suggesting that SOC:clay ratios precisely characterized the fields. Due to the high SOC:clay ratios found, we conclude that there is limited opportunity to market additional carbon sequestration as an asset class in the North Devon Biosphere or similar areas. Instead, preserving existing SOC stocks would be a more suitable ecosystem service payment basis.

English

Two isothermal unsteady motions of the incompressible Burgers fluids between infinite horizontal parallel plates are analytically and numerically investigated when a differential expression of the shear stress is prescribed on the lower plate. Closed-form expressions are established for the dimensionless permanent velocity fields and the corresponding shear stresses. They seem to be the first exact solutions for such motions of Burgers fluids. The corresponding permanent solutions for Oldroyd-B, Maxwell, second grade and Newtonian fluids performing similar motions can immediately be obtained as limiting cases of general solutions. The obtained velocity fields are used to determine the needed time to reach the steady state for the respective motions. It was found that the steady state for such isothermal motions of the incompressible non-Newtonian fluids is earlier obtained for the Burgers fluids in comparison with Oldroyd-B or Maxwell fluids.

Dynamics of the Soil Macrofauna Influenced by Improved Fallows With Andropogon gayanus in Hydromorphic Soil at Bondoukuy (Western Burkina Faso)

In western Burkina Faso, in the Bondoukuy cotton zone, on silty-clay soils, the rarefaction of the perennial grass Andropogon gayanus, characteristic of old fallows, is noticed. This grass is known to restore the structural stability of the soil rather quickly, due to a stimulation of biological activity, while the storage of organic matter in the soil remains slow. The biological aspect has been prospected through the study of invertebrate populations in 3 sites, all of which present 4 situations: 30-year-old fallows, 5-year-old natural fallows, and 5-year-old A. gayanus improved fallows and 10-year-old permanent crop fields.
 
 The results show that invertebrate populations are very diverse. A total of 172 morphotypes were recorded, including 115 species of insects (24 species of social insects), 31 species of Chelicerata, 8 Myriapoda and 5 earthworms. In the fields, earthworms and Diplopoda populations are less important than in old fallows. On the other hand, the fields have the highest species diversity, 50 species on average. The most abundant population is found in natural fallows, with a density of 835 individuals/m² and 43 species represented. Improved fallows with A. gayanus have a lower stand density and species richness than natural fallows (less than 50% and 43 species). In old fallows, stands are stable with a richness limited to 30 species, while earthworms and myriapods have significantly reduced densities.
 
 Soil invertebrate communities thus recover rapidly after crop abandonment and are fully active during the most intense phase of recovery in the first 5 years. Trees do not appear to have a significant effect on the conservation and stimulation of macrofauna except for Coleoptera.
 
 Our results show that the cropping system adopted in the region allows for minimal conservation of soil macrofauna and that the macrofauna recovers rapidly during the fallow. Improved fallows with A. gayanus differ from natural fallows in limiting Termite density, while old fallows and fields are of comparable density.

The Carrying Capacity Analysis of Rice Plants Agriculture to Fulfill Food Needs in Pati Regency

The fulfillment of food needs is one indicator of community welfare. The calculation of the carrying capacity of food crops is used to determine the extent to which an area meets its food needs. The aims of this study were: (1) to calculate the level of carrying capacity of rice plants in Pati Regency, (2) to plan land that has the opportunity to be used as a LP2B area, and (3) to find out the maximum population and year in Pati Regency to meet food needs. The technique of analyzing the carrying capacity of rice plants uses the calculation of the carrying capacity of natural resources and the analysis of determining land that has the potential to become sustainable food cropland using an overlay map analysis with ArcGIS. The results showed that the value of the rice plant commodity had a carrying capacity value of more than 1, which was 1,371. The results of the map-making, the land that has the opportunity to be used as permanent rice fields is 50.635 hectares. The maximum population that can be met by annual rice production is 1.622.356 people. The results of population projections using the geometric method, the maximum year Pati Regency can be self-sufficient in food is 2040. The fulfillment of sustainable food needs can be realized through monitoring the implementation of the LP2B program so that the conversion rate of agricultural land can be minimized.
 Keywords : Carrying Capacity; Rice Plants; Food Needs
 
 Copyright (c) 2022 Geosfera Indonesia and Department of Geography Education, University of Jember
 This work is licensed under a Creative Commons Attribution-Share A like 4.0 International License

Research on Soil and Nutrient Losses through Liquid Runoff, in Order to Mitigate the Climate Risks to Which Romania Is Exposed, in the Context of CAP

The current paper presents the monitoring of soil and nutrient losses through runoff as the result of the climate change. The experimental results were recorded on the standard plots for runoff and erosion control. The results of the studies carried out highlight that total nitrogen losses range from 0.05 kg/ha to 12.60 kg/ha, potassium displaced from the plots has values between 0.02 and 1.35 kg/ha, the humus associated with the eroded soil includes values between 0.51 and 176.5 kg/ha, phosphorus is recorded with maximum values of 0.39 kg/ha, the total iron losses have values between 3.14 and 431.16 g/ha, manganese has losses from 1.69 to 290.82 g/ha, copper losses range from 0.15 to 7.62 g/ha, and, regarding zinc, the values are within the limits of 0.25–57.22 g/ha. The maximum values of the displacement of fertilizing elements from the sloping agricultural lands, by means of liquid and solid leaks, are registered at the plots left as permanent black fields, the plots practically unprotected against the rain erosion. The experiments were performed at the Soil Erosion Research and Development Station “Mircea Moțoc”, Perieni/Staţiunea de Cercetare Dezvoltare pentru Combaterea Eroziunii Solului “Mircea Moţoc”, Perieni (SCDCES—MM, Perieni), Vaslui County, an institution strategically located in an area subject to erosion soil. Additionally, the paper envisages how the National Rural Development Programme (NRDP) and the Common Agricultural Policy (CAP) can be of use in this area by analysing past lessons and providing an overview of what was done.

High-speed permanent magnet machine multi-physics fields design for turbine application

This paper presents the multi-physics fields research of a high-speed permanent magnet machine (HSPMM) for turbine application. At first, the design considerations for the HSPMM are introduced and presented. Then, the machine electromagnetic performances are comprehensively studied with machine stator slot numbers. Moreover, the influences from the PM magnetization methods and segmentation number on PM eddy current loss reduction are further investigated. Thermal analysis is also performed for the HSPMM with the cooling water fluid volume flow rate considered. In addition, rotor strength is studied for the HSPMM with several design factors on machine rotor strength performances further studied and researched.

The spread of agriculture in south-eastern Europe: new data from North Macedonia

North Macedonia is a crucial region for understanding the spread of agriculture into the Mediterranean and Central Europe. To date, however, the area has been subject to relatively limited archaeological research. Here, the authors present use-wear and archaeobotanical analyses on material from two Neolithic sites, Govrelevo and Vrbjanska Čuka, to investigate practices that were previously unstudied in this part of the Balkans, such as sowing, cultivation and harvesting techniques. The results suggest the presence of permanent crop fields located in wetlands, with autumn and spring sowing, and harvesting using curved sickles. The study illuminates early agricultural practices in North Macedonia and adds to our knowledge of the spread of the Neolithic package across Europe.

Humus Content in Soil and Yield in the Permanent Cotton Cultivated Fields

The article presents the data of a long-term experience on the reproductive capacity of the soil during the permanent cultivation of cotton, which has been carried out for 96 years at the Institute of Breeding, Seed Production and Agrotechnology for Growing Cotton in the Kibray district of the Tashkent region. The article presents the results of analyses by determining the content of humus, from which it can be seen that the decrease in humus was more marked on the control variant without fertilizers, and the amount of humus decreased after 20 years compared to the initial indicator by 11.4 t/ha, after 40 years 16 46 t/ha, after 60 years by 19.05 t/ha, after 80 years by 26.29 t/ha and after 96 years by 29.17 t/ha. It was also determined by the decrease in humus content in option 2, where NPK 250:175:125 kg/ha was applied annually, respectively: 6.487 t/ha; 9.225 t/ha; 10.09 t/ha; 16.95 t/ha; 19.65 t/ha; with an annual application of 30 t/ha of manure + 25 kg/ha of P2O in option 1, respectively: 0.335 t/ha; 3.683 t/ha; 11.40 t/ha; 22.44 t/ha; 32.58 t/ha. In addition, the article also provides data on the yield of cotton by options for permanent cultivation. It was determined that in the control variant, the yield decreased from 16.8 centners per hectare to 9.9 centners per hectare; in the variant where NPK was applied every year 250:175:125 kg/ha was 31 - 34 c/ha, where 30 t/ha of manure + 25 kg/ha P2O 29 - 32 c/ha were used every year.

Agriculturización

Although the importance of agriculture as a key factor in the economic development of Andean peoples and territories has been widely recognized worldwide, there have been few attempts to assess its historical importance in the construction of pre-Columbian agricultural landscapes in the Andes of Ecuador. This article presents the first results of the analysis of the Kañari agrarian landscapes in the upper Chanchán basin, showing a long historical trajectory that spanned almost 2000 years from the Late Formative Period (543-381 cal BC) to the final phase of the Integration Period (1386-1438 cal AD). Extensive and intensive farming systems (permanent fields and terraces) acted as a transforming agent of the space, imprinting an agro-sacralized cultural signature with the configuration of three types of landscapes: Domestic, Social and Sacred. The agriculturization of these landscapes shows how the intensification of agriculture under a unilinear progression model does not generally mean a natural retreat of ecosystem processes, due to human intervention for the production of its crops. The elasticity of the pre-Hispanic Kañaris agroecosystems could be sustained in the face of the historical processes of agriculturization throughout its historical trajectory.

The association between foot temperature and hoof lesions in sheep

Lameness, predominantly caused by footrot and interdigital dermatitis, is a common issue in sheep flocks with negative consequences for animal welfare and productivity. Simple and cheap methods to prevent and monitor lameness are desirable to decrease prevalence within flocks. The aim of this study was to investigate whether a high foot temperature threshold can be used as an early warning for the development of hoof lesions and lameness in sheep. A flock of 47 pregnant ewes and seven non-pregnant ewe lambs were randomly allocated into two equal groups and placed in two different but similar permanent pasture fields for the duration of the study. Foot temperature was measured with a temperature probe placed on the interdigital skin on three dates over approximately 4 weeks. This study showed that increased foot temperature was associated with higher lesion scores (recorded lesions covered a scale of 0 to 3), with healthy feet having a mean temperature of 20°C and feet with severe lesion scores having a mean temperature of 31°C. Also, back feet had a higher foot temperature and lesion score than front feet (P<0.001). This study suggests that a threshold of 26.5°C in the back feet of sheep (mean foot temperature for a lesion score of 1 in back feet) could be used as an indication of when to foot bath or treat feet, and minimise hoof lesions in sheep.

Experimental Installation for Determination of Attenuation Coefficient of Permanent Magnetic Field by Protective Materials

The permanent magnetic field in addition to electromagnetic radiation has a significant effect on performance of devices. This is particularly true for highly sensitive precision measuring equipment, such as, for example, magnetometers or photomultiplier tubes. In this regard a new high-performance materials for protection against permanent fields and electromagnetic radiation need to be developed. The purpose of this paper is a development of a hardware and software complex for high-precision determination of permanent magnetic field attenuation coefficient and certification of protective materials.This paper describes an experimental installation for determining the attenuation coefficient of a permanent magnetic field using materials and coatings on standard package for electronic equipment. The installation ensures a uniform magnetic field flow in the measurement volume. The advantage of the measuring device is the ability to measure magnetic field in three coordinates due to the use of three pairs of Helmholtz coils and a three-dimensional Hall sensor. The software will enable to control of the magnetic field in all three directions, simulating the real operating conditions of devices that require protection from such influences. In addition, a movable positioning system makes it possible to compensate for the Earth's magnetic field, which increases the accuracy of estimating the attenuation coefficient by protective materials in weak magnetic field.An alternative use of the capabilities of the installation is to test the performance of the devices in a permanent magnetic field and evaluate the electromagnetic compatibility. Experimental results of the work includes determination of the magnetic field attenuation coefficient using standard photomultiplier tube package made of electrolytically deposited permalloy and the sheet of annealed permalloy. Thus, the effect of annealing and closed magnetic circuit on the degree of weakening of the magnetic field is shown. It has been demonstrated that annealing which causes a significant increase in the magnetic permeability promotes an effective attenuation of weak magnetic fields (up to 1 mT). In magnetic fields with an induction of 1 mT or more, effective attenuation is provided by a closed magnetic circuit.

Understanding cotton cultivation dynamics in Aksu Oases (NW China) by reconstructing change trajectories using multi-temporal Landsat and Sentinel-2 data

Understanding spatiotemporal dynamics of cotton cultivation patterns is an essential input to cotton farming management, production prediction and policy formulations. Thus, this study demonstrates cotton cultivation dynamics by constructing their change trajectories using multi-temporal Landsat and Sentinel-2 images. Then we reclassified the trajectories into four change trends, namely permanent cotton-field, cotton-field gain, cotton-field loss and unstable changes type. The results showed that increased cotton-cultivated areas were greater than the decreased areas. Cotton fields’ expansion gradually appeared in the outer parts of the permanent cotton fields, especially towards the northern mountain front alluvial-plain. Production decline caused by cotton cultivation loss was 3.09 × 108 kg. The observed cotton cultivation dynamics were associated to farmers’ options driven by crop price fluctuations, agricultural policies and natural conditions. The production loss was associated to cotton field loss and fields that underwent unstable changes. Management strategies should thus focus intercepting the loss and the unstable change trajectories.

Dry Matter Production Response of Non-conventional Pineapple (&amp;lt;i&amp;gt;Ananas comosus &amp;lt;/i&amp;gt;L.) Seedling to Nursery Media Preparation

Establishment and management of pineapple production mainly lie on the production and supply of quality planting material with desirable root and shoot growth characteristics. Farmers in the South Ethiopia, uses different parts of pineapple like ground sucker, slips, and also crown sucker to transplant to the permanent fields. The fertilization practices were also not common, some farmers use to apply organic fertilizers like animal dung at the permanent field while there is no any media information generated to seedling production. Therefore, this study was conducted to examine the dry matter Production responses of non-conventional pineapple Seedling to organic based nursery media Preparation. The experiment was arranged in RCBD with three replication and six treatments. Six treatment combinations of compost to topsoil ratio in (0:1), (1:1), (1:2), (1:3) (1:4) and compost only (1:0). All the relevant parameters were collected and computed using SAS software. Treatment means were separated using LSD at 5% probability. The results revealed significant variation among the treatments that indicated, the soil based nursery media of compost (1:0) and (1:1) ratio of compost to topsoil responded the best dry matter production response of pineapple seedling in terms of, leaf fresh weight, leaf dry weight, root dry weight and total plant dry biomass. This result suggested that compost (1:0) and or compost to topsoil in (1:1) ratios was useful media to produce the best growth of pineapple seedling before transplanting to its production field.

From Late Prehistory to the Foundation of Early States in Inland Southeast Asia: a Debate

Mortuary data from three Iron Age sites in Northeast Thailand and three in Northwest Cambodia are here reviewed for information on social formation on the cusp of early states. It has been suggested that the three Cambodian sites present evidence for a complex polity with three social tiers and that this contrasts with the lack of any evidence for equivalent complexity in the three communities in the upper Mun Valley of Northeast Thailand. This model is examined and queried on the basis of insufficient data for the Cambodian sites, and contestable statistical analysis. In its place, an alternative is presented, that identifies a critically important climatic deterioration causing increased aridity which stimulated the development of plough-based wet rice cultivation in irrigated permanent fields. In the upper Mun Valley of Northeast Thailand, this coincided with a swift rise in social elites, interred in lineage-based nuclei in which leading individuals were accompanied by unprecedented wealth. Within a century or two, some Iron Age settlements greatly expanded into regal centers documented through texts that mentioned the state of Sri Canasapura. This transition might also have occurred in Northwest Cambodia at the same time, but evidence for this is so far unconvincing.

Direct Look at the Electric Field in Ketosteroid Isomerase and Its Variants

Enzymes catalyze a number of reactions with high efficiency and stereoselectivity. It is thought that strong, direct, and permanent electric fields within the active site of the enzyme contribute t...