Academic literature on the topic 'Soil texture type'

Chlorpyrifos is widely used by farmers as a contact poison to control leaf and fruit pests in red chilies. Chlorpyrifos is very toxic to the environment and to living things, although it is easily degraded and has a short half-life. Remediation materials in the form of activated charcoal, biochar, and microbial consortium are effective remediation technologies to reduce insecticide residues. Each compound has different characteristics based on the type and texture of the soil. Research with the aim of determining the ability of remediation agents in reducing chlorpyrifos insecticide residues was carried out in the screen house of the Agricultural Environment Research Institute between May-November 2017. The results showed that the effectiveness of reducing chlorpyrifos residue in the soil was different according to its texture. Application of 2 l / ha of consortium microbes was effective in lowered chlorpyrifos residue in lightweight-texture soils, while biochar-coated urea was effective in reducing chlorpyrifos residues in weight-textured soils. Urea coated with activated charcoal showed relatively stable red chilli yields in the two types of soil textures.

Soil phosphorus (P) deficiency is a major constraint of crop production in Sub-Saharan Africa. In particular, in the Sudano-Sahelian zone of Burkina Faso, P is rarely replenished as fertilizer supplies are limited in rural areas and because of the socio-economic situation of farmers. There is however, an abundance of local phosphate rock resource in the country. The development of local inorganic P fertilizers to improve crop production and replace the nutrients removed after harvesting, as well as to promote to sustainable agriculture, is desired. This study evaluated the efficiency of low-grade Burkina Faso phosphate rock (BPR)-based P fertilizers, produced by acidulation and calcination-the major fertilizer processing methods, on lowland rice production and the soil factors influencing their effectiveness. The results showed that the acidulated P fertilizers were as effective as conventional commercial P fertilizers on various soil types, textures, and fertility. Calcined P fertilizers were consistently effective on fine-textured soils with high basic fertility. It was found that fine soil texture and basic fertility of the initial soils were important factors in agronomic efficiency of BPR-based fertilizers and the resilience of rice production to climatic variability. It is recommended that soil type, with respect to soil texture, soil properties, inherent fertility, and water availability, should be considered when using BPR-based fertilizers for rice cultivation.

Soil properties and earthworm population density were examined for 5 forest soils derived from Silurian-Devonian sandstones (Mathinna Beds) in north-eastern Tasmania. The soils occur along gradients of altitude, rainfall, and forest type; they include 2 with texture-contrast and 3 with gradational soil profile types. The density and biomass of the most abundant earthworm species Megascolex montisarthuri, and of all earthworm species combined, were found to be greater in gradational than in texture-contrast soils. A greater proportion of the earthworms in gradational soils than in texture-contrast soils was found to occur at soil depths exceeding 10 cm. The contrast was most pronounced between the 2 texture-contrast soils and the single gradational soil that occur under dry eucalypt forest. This paper explores the hypothesis that bioturbation of surface and subsurface layers by earthworms is an important mixing process that in gradational soils outweighs the counter tendency for soil particles to sort and thus form texture-contrast profiles.

A survey of 71 sites was conducted in the dairying districts of south-western Victoria in October 1994 to determine factors associated with nitrogen (N) fixation in white clover based pastures. Twenty-eight factors (environmental, microbiological, management, soil, and pasture) were considered in relation to 2 indicators of N fixation by white clover, %Ndfa (percentage of total plant N derived from the atmosphere, as determined by the 15N natural abundance method) and kg of N fixed per tonne herbage dry matter (legume and non-legume). On light-textured soils (sandy loams), soil potassium, rhizobia numbers, total soil N, and density of the nematode Pratylenchus sp. accounted for 72% of variation in %Ndfa. On medium-textured soils (clay loams), crude protein of perennial ryegrass and plant-available phosphorus in the soil accounted for 30% of variation in %Ndfa. The amount of N fixed was influenced by different factors, again depending on soil texture. Soil chemical properties accounted for 31% variation on the medium-textured soils with nematode density, pasture quality, and soil chemical properties accounting for 77% of variation on light-textured soils. Amounts of N fixed per tonne herbage dry matter produced averaged 8.2 kg on the light-textured soils and 7.3 kg on the medium-textured soils. Average %Ndfa values were 67% and 60% on light- and medium-textured soils, respectively. Effects of soil texture on N fixation were attributed to the different cation exchange and water-holding capacities of the soils and highlight the importance of considering soil type in N fixation studies.

The background concentrations of hydrocarbons (HCs) were estimated for soils of the northernmost and northern taiga ecosystem of the Komi Republic. It was shown that accumulation and distribution of hydrocarbons in soil cover is regulated by following pedological factors: texture class, parent material and landform type and the type of soil forming process. In all studied soils of accumulative positions showed more pronounces accumulation of hydrocarbons than the soils of well-drained eluvial positions. Interprofile differentiation of hydrocarbons content is more expressed in clay-textured soils than sandy ones.

Accurate mapping the spatial distribution of different soil textures is important for eco-hydrological studies and water resource management. However, it is quite a challenge to map the soil texture in data scarce, hard to access mountainous watersheds. This paper compares a nonlinear method, the Markov chain random field (MCRF) with a classical linear method, ordinary kriging (OK) for calculating the soil texture at different search radiuses in the upstream region of the Heihe River Watershed. Results show that soil texture values that were calculated by the OK method tends to predict soil texture values within a certain range (sand (12.098~40.317), silt (47.847~71.231), and clay (12.781~19.420)) because of the smoothing effect, thus leading to greater accuracy in predicting the major soil texture type (silt loam). Nonetheless, the MCRF method considers the interclass relationships between sampling points, leading to greater accuracy in predicting minor types (loam and sandy loam). Meanwhile, the OK method performed best for all the types at the radius of 65 km influenced by the densities of all the sampling points, while the best performance of the MCRF method differs with radiuses as the largest densities varying for different soil types. For loam and sandy loam, the OK method ignored them, thus the MCRF method is more suitable in mountainous areas with high soil heterogeneity.

Purpose: To investigate the effect of different soil textures on chemical composition and antioxidant properties of essential oils from Solanum nigrum. Methods: Four soils of differing texture were formulated from soil under fallow to cultivate S. nigrum in a glasshouse. Essential Oil was extracted from fresh shoots by solvent-free microwave extraction (SFME) and analysed using gas chromatography-mass spectrometry (GC-MS). Antioxidant properties were assayed (DPPH) and ABTS Results: GC-MS profiling revealed variations in the quality index (QI), number of chemical constituents and antioxidant results of S. nigrum oil. Geraniol and citronellol were the two principal components. The highest activity of the antioxidant was found in plants cultivated on clay loam soil. Fifty percent (50%) Inhibitory Concentration (IC50) ranged from 1.196 to 1.594 μg/mL and 0.067 to 3.59 μg /mL in DPPH and ABTS assays, respectively. Conclusions: This research work indicates that soil texture influences the oil quality, quantity and chemical composition of oil extracted from S. nigrum shoots. Essential oil extracts from S. nigrum grown on clay loam soils recorded the highest antioxidant properties.

Abstract In this second part of a two-part paper, the impacts of soil texture and vegetation type misclassification and their combined effect on soil moisture, evapotranspiration, and total runoff simulation are investigated using the Noah model. The results show that these impacts are significant for most regions and soil layers, although they vary depending on soil texture classification, vegetation type, and season. The use of site-observed soil texture classification and vegetation type in the model does not necessarily improve anomaly correlations and reduce mean absolute error for soil moisture simulations. Instead, results are mixed when examining all regions and soil layers. This is attributed to the compensation effects (e.g., effect of ill-calibrated model parameters), as Noah has been more or less calibrated with model-specified soil texture classification and vegetation type. The site-based analysis shows that Noah can reasonably simulate the variation of daily evapotranspiration, soil moisture, and total runoff when soil texture classification (vegetation type) is corrected from loam (forest) to clay (grasslands) or vice versa. This suggests that the performance of Noah can be further improved by tuning model parameters when site-observed soil texture and vegetation type are used.

Average percentages of soil material > 0.84 mm diameter estimated from wind erodibility groups (WEG) are commonly employed in the appraisal of the wind erodibility of soils. Soil samples taken after seeding from four areas of Alberta were sieved on a Modified Rapid Rotary Sieve. Agreement between the sieving data and estimates of material > 0.84 mm made using the WEG was poor (r = 0.33). Samples from soil textural groups generally had twice as much material > 0.84 mm than predicted by the WEG. Using 350 soil samples the relationship between soil aggregates > 0.84 mm and (1) field estimated soil properties, and (2) soil management was investigated by multiple regression analysis. Aggregation was strongly dependent on soil texture (r = 0.67) with coarser-textured soils having fewer aggregates > 0.84 mm and thereby being more erodible. Increasing quantities of soil carbonates (up to 10%) increased soil erodibility. Preseeding tillage decreased erodibility. Conversely, postseeding packing operations increased erodibility except when a rodweeder was used. Type of seeding implement, rotations, and type of crop seeded (oilseeds versus grains) had no statistically significant effect on aggregation. The coefficient of multiple determination (R2) for the final model was 0.61. Results were corroborated by previous experimental findings and confirmed that the WEG are not accurate for Canadian Prairie soils. The study demonstrated that although soil texture and carbonate content played an important role, tillage had a considerable effect on soil erodibility. Key words: Wind erosion, soil erodibility, WEG, aggregation, soil management

Soil type is an important factor affecting the growth of lupins. Successful lupin cultivation is generally restricted to deep, acid to neutral, coarse-textured soils. Very little is known about the factors affecting the performance of lupins on other soil types. This review attempts to define the major factors controlling the growth of lupins of fine-textured, alkaline soils, with a view to providing a focus for future research. Wild populations of the genus, as a whole, occupy soils of a wide pH and textural range (pH 4-8.5, texture ranging from coarse sands to fine clays), although the majority of populations are found on light soils of sandy loam or loamy sand texture with pH values between 5.5 and 7. Species within the genus have distinct preferences for soils of a narrower range than the genus as a whole. Commercially cultivated species appear to be adapted to a narrower range of soil types than the wild species. Iron nutrition, seedling emergence, and rooting pattern and phenology are the major factors influencing the performance of lupins on fine-textured, alkaline soils. Lupins appear to possess some mechanisms thought to enhance the availability of Fe, nevertheless they suffer severely from Fe deficiency. Conditions prevailing on fine-textured, alkaline soils (poor drainage and aeration, CaCO3) are frequently conducive to Fe deficiency. The epigeal pattern of emergence of lupins is unsuitable to fine-textured soils, particularly if crust formation occurs. The rooting pattern and phenology of lupins is better suited to deep sandy soils than shallow, fine-textured soils, and this exacerbates late-season water stress. A better understanding of these factors may allow breeding and management strategies to be developed which will extend lupin cultivation to a wider range of soils.

Clomazone is an effective herbicide widely used for preemergence grass control in rice. However, use of clomazone on sandy textured soils of the western Texas rice belt may cause serious rice injury. When labeled for rice in 2001, sandy textured soils were excluded. Laboratory experiments were conducted to determine the effect of soil characteristics and water potential on plant-available clomazone and rice injury. A centrifugal double-tube technique was used to determine plant-available concentration in soil solution (ACSS), total amount available in soil solution (TASS), and Kd values for clomazone on four soils at four water potentials. A rice bioassay was conducted parallel to the plant-available study to correlate biological availability to ACSS, TASS, and Kd. TASS was significantly different in all soils at the 1% level of significance. The order of increasing TASS for the soils studied was Morey Edna Nada Crowley which correlated well with soil characteristics. Two field experiments at three locations were conducted in 2002 and 2003 to determine the optimum rate range that maximizes weed control and minimizes crop injury across a wide variety of soil textures and planting dates. At Beaumont, Eagle Lake, and Ganado, TX, preemergence application of 0.41 to 0.56, 0.38 to 0.43, and 0.36 to 0.42 kg ha-1 clomazone, respectively, provided optimum weed control with minimal rice injury. Data suggests that clomazone is safe to use on rice on sandy textured soils. Injury may occur, but, rates suggested from this research will minimize injury and achieve excellent weed control. As a result, amendments to the herbicide label will allow clomazone use on sandy textured soils giving rice producers more flexibility and access to another effective herbicide.

Thesis (MSc)--Stellenbosch University, 2004.
ENGLISH ABSTRACT: Bush encroachment in savannas leads to reduced diversity, productivity and profitability of rangelands. This holds important implications for the livestock and eco-tourism industries, as well as for subsistence ranchers in the South African semi-arid savannas, who depend on this vegetation type for economic and livelihood purposes. Soil moisture, nutrients, rue and herbivory are generally regarded as the principal factors determining vegetation structure and function within savannas. The factors and processes involved in the determination of the tree:grass ratio within savannas are, however, not clearly understood. We investigated the role of soil type and management strategy (cattle, game and communal grazing) in the determination of the presence and distribution of plant species in general, and on the presence and distribution of the encroaching tree species, Acacia mellifera, specifically. Both shortand long-term trends were investigated. The study area, the Kimberley Triangle, (Northern Cape Province, South Africa), was ideal for this kind of study because it has different management strategies practised on several soil types, and bush encroachment is a widespread phenomenon. Contrary to the belief that heavy livestock grazing is the main cause of increases in the tree:grass ratio, we found that soil type, through its effects on plant growth and on the presence and availability of soil moisture and nutrients, is more important in determining vegetation composition than management strategy. It was found that the various types of grazing management mainly influenced vegetation structure and function by affecting the competitive interactions between Ns-fixing woody species and non-Ns-fixing grasses. Of the soil factors affecting vegetation composition, soil texture was a good indicator of the physical conditions for plant growth in an area, and also of the presence and availability of soil moisture and nutrients. We found that sand and clay soils are relatively resistant to bush encroachment as compared to loamy-sand and -clay mixes. This is because woody growth is impaired in the first-mentioned habitats by soil texture, soil moisture regimes and heavy utilisation. In soils with combinations of loam, sand and clay, soil texture and moisture are not limiting to woody growth and if the repressive competitive effect of grasses on woody vegetation is removed, opportunities are created for recruitment of woody species and encroachment. Additionally, rockiness increases soil moisture infiltration. In the study area, woody species, and specifically A. mellifera, are associated with these areas. We suggest that in the study area, rocky areas are naturally encroached. This is in agreement with the patchdynamic approach to savanna vegetation dynamics. Because soil moisture is such an important factor in the determination of the tree:grass ratio in the study area, we further suggest that in above-average rainfall years, when soil moisture conditions are optimal for woody seed germination, establishment and growth, heavy grazing should be avoided, as it would provide the opportunity for encroachment. Keywords: Bush encroachment; N2-fixing species; game, cattle, communal grazing; soil texture; soil moisture; soil nutrients; Acacia mellifera; tree-grass competition.
AFRIKAANSE OPSOMMING: Bosindringing in savanna gebiede het verlaagde diversiteit, produktiwiteit en winsgewendheid van natuurlike weivelde tot gevolg. Behalwe dat dit die Suid-Afrikaanse vee- en ekotoerisme bedrywe raak, is verskeie bestaansboerderye afhanklik van die plantegroei-tipe vir oorlewing. Grondvog, grondvoedingstowwe, vuur en beweiding word algemeen aanvaar as die belangrikste faktore wat die struktuur en funksie van savannas bepaal. Daar is egter nog nie duidelikheid oor die prosesse wat betrokke is in die bepaling van die boom-gras verhouding in savannas nie. In dié studie het ons ondersoek ingestel na die invloed van grond tipe en beweidingstrategieë (beweiding deur beeste, wild, of kommunale beweiding) op die algemene verspreiding van verskillende plant spesies, en ook op die van die indringer spesie, Acacia mellifera. Beide kort- en lang-termyn patrone is ondersoek. Die studiegebied, die Kimberley Driehoek in die Noord-Kaap, Suid-Afrika, was ideaal vir so 'n ondersoek omdat verskillende beweiding strategieë op verskeie grond-tipes beoefen word maar bosindringing steeds 'n algemene verskynsel in die gebied is. Ons bevinding was dat, ten spyte van die feit dat daar oor die algemeen geglo word dat swaar beweiding die hoof oorsaak van bosindringing is, grond-tipe belangriker is in die bepaling van die spesie-samestelling van 'n gebied. Dit is as gevolg van die feit dat grond-tipe die groei van plante beïnvloed deur die teenwoordigheid en beskikbaarheid van grondvog en -nutriënte te bepaal. Die verskillende beweidingstrategieë beïnvloed meerendeels die kompetatiewe interaksies tussen N2-bindende hout-agtige spesies teenoor nie-Nj-bindende gras-agtige spesies. Grond-tekstuur was 'n goeie aanduiding van die algemene toestande vir plantegroei en ook van die teenwoordigheid en beskikbaarheid van grondvog en -nutriënte. Ons het bevind dat sand en klei grond, relatief tot leem, sand en klei kombinasies, weerstandbiedend is teen bosindringing as gevolg van die tekstuur, water-regimes en swaar beweidings vlakke wat op die grond-tipes voorkom. Omdat grond-tekstuur en grondvog nie beperkend is op die leem-, sand- en klei-grond kombinasies nie, kan bosindringing maklik hier voorkom as die onderdrukkende effek wat grasse op houtagtige plantegroei het, deur swaar beweiding verwyder word. A. mellifera is ook oor die algemeen met klipperige gebiede geassosieer omdat klipperigheid lei tot verhoogde infiltrasie van grondvog. In die studie-gebied is klipperige areas dan ook van nature ingedring deur A. mellifera. Dit stem ooreen met die siening dat savannas bestaan uit "laslappe" van verskillende plantegroei (patch-dynamic approach). Dit was duidelik dat grondvog 'n belangrike bepalende faktor is in die bepaling van die boom-gras verhouding in die studiegebied. Ons stel dus voor dat in bo-gemiddelde reënval jare, swaar beweiding vermy moet word, omdat houtagtige saailinge gedurende die tydperke maklik kan ontkiem en vestig juis omdat grondvog dan nie beperkend is nie. Sleutelwoorde: Bosindringing; N2-bindende spesies; bees, wild, kommunale beweiding; grond tekstuur; grond-vog; grond-nutriënte; Acacia mellifera; boom-gras kompetisie.

Le but de cette etude est l'identification et la comprehension des mecanismes gouvernant le comportement thixotrope dans les dispersions aqueuses d'une argile de type hectorite : la laponite. Cette argile modele, constituee de particules anisotropes de taille nanometrique, a permis de combiner les mesures rheometriques avec des mesures de diffusion de rayonnements, des visualisations du champ de deformation et des mesures de birefringence. Au repos, la structure des gels est constituee d'agregats microniques denses assembles en une masse fractale d'une dimension d. Pres de la transition sol-gel, d = 1, la texture est fibreuse. Aux fractions volumiques plus elevees, d = 1,8, la structure est une connexion de zones denses et de zones moins denses en particules. Des lois d'echelles theoriques et experimentales, ont permis de correler ces dimensions fractales a l'influence de la fraction volumique sur le seuil d'ecoulement. La transition sol-gel et la stabilite de la phase gel ont ete etudiees en fonction du temps de gelification et des parametres physico-chimiques. L'existence d'instabilites d'ecoulements, telle que la localisation du cisaillement, ont ete montrees, sur ces dispersions dont la courbe d'ecoulement est a minimum de contrainte. Les differents regimes d'ecoulements ont ete identifies et ont permis d'etablir des procedures fiables pour la caracterisation du comportement thixotrope. Sous ecoulement de cisaillement, la chute de viscosite provient d'orientations et de desagregation a l'echelle de longueur de l'ordre du micron. Lors de la restructuration, les deux echelles de temps mises en evidence, correspondent respectivement a une relaxation rapide des orientations et a un processus lent d'agregation. La nature du comportement thixotrope est alors identifiee comme etant principalement un processus d'agregation reversible, pour lequel les grandes echelles de longueur, de l'ordre du micron, associees a un arrangement fractal jouent un role determinant.

MSCAGR (Soil Science)
Department of Soil Science
The effects of tillage on soil structure and associated soil properties such as soil respiration may differ in different soils. The study determined the effects of tillage, soil texture and mineralogy in selected soil properties on different soil types. Soil samples were collected from four different sites in the Limpopo province, South Africa. The soils were classified as Glenrosa with sandy loam texture, Dundee with loamy sand, Hutton with clay, and Shortlands with clay. Glenrosa and Dundee were dominated by quartz, while Hutton and Shortlands with kaolinite. Soil samples were taken from the surface 0 – 20 cm under conventional tillage and no-till land. Soil organic matter, texture, and mineralogy were determined. The soils were wetted to activate the microorganisms and incubated for 70 days at 30℃ and soil respiration was determined using alkali trap method on a weekly basis. The study was conducted in triplicates and arranged in a completely randomized design. Data was subjected to analysis of variance using general linear model procedure of Minitab version 19. Means were compared using paired t-test at (p ≤ 0.05). The Pearson correlation coefficient (r) was used to measure the strength of linear dependence between variables. There was a significant difference in soil organic matter (p≤0.000) among all studied soils. The mean values of soil organic matter were 2.19% in Hutton, 2.0% in Shortlands, 0.54% in Glenrosa, and 0.43% in Dundee. Quartz had a strong negative linear relationship (r = -0.66) with soil organic matter while kaolinite had a strong positive linear relationship (r = 0.96). Soil respiration increased in soils dominated with quartz and decreased in soils dominated with kaolinite. The soil respiration increased by 18.95 g CO2 m-2 d-1 in conventional tillage and decreased by 13.88 g CO2 m-2 d-1 in no-tillage due to increased exposure of soil organic matter under conventional. It was concluded that less intensive tillage such as no-tillage reduces soil respiration.
NRF

MSCAGR
Department of Soil Science
Soil hydraulic and hydraulic-related physical properties are key to soil productivity and these properties are widely studied. Nevertheless, their spatial variability is least understood. Two sites were selected for this study (University of Venda Experimental farm and Roodeplaat, Agricultural Research Council farm). The objectives of this study were to determine the spatial variability of soil water content, water infiltration and hydraulic conductivity on selected soils. Field measurements were done on a 20 m × 20 m. Soil hydraulic and hydraulic-related physical properties were studied at two depths, 0 – 0.2 m top soil and 0.2 – 0.4 m sub soil. The field was irrigated to saturation and let to drain freely for two days. The soil was quickly secured in water cans to avoid further loss of water by evaporation and taken to the laboratory for analysis. Data was analysed using ordinary kriging method in ArcMap® software version 10.4 to generate spatial variability maps and semi variograms. The University of Venda Experimental farm had lesser spatial variability with coefficient of variation ranging from 9.6 to 33.4%. The spatial variability of soil was very low confirmed by contour maps depicting slightly homogeneity. Whereas, the soil hydro-physical properties displayed greater spatial variability at Roodeplaat, Agricultural Research Council Experimental farm. The empirical variograms of spherical model fits were also assuming weak spatial dependence with a curve variogram. The coefficient of variation ranged from 10.5 to 51.9%. Therefore, the greater variability at Roodeplaat, Agricultural Research Council Experimental farm indicated that coarse soil texture under conventional tillage has a greater influence on the spatial variability of the soil hydro-physical properties.
NRF

This thesis is an investigation of nitrogen availability from manure as affected by application timing, soil type and manure type. This trial was conducted on three different sites in Southwestern Ontario, each consisting of a different soil hydrologic group. Also assessed were liquid hog manure, solid cattle manure and solid poultry manures applied to plots at three different timings (late summer, fall and spring) to determine nitrogen. A coarse soil had a higher amount of nitrate in the fall compared to finer textured soils. Manures did not have a significant interaction with application timing. It was apparent that high inorganic nitrogen manures such as liquid hog provided the most nitrogen to a corn crop while solid beef manure provided the lowest. It was found that there was a barley response to residual nitrogen in the following year of application; however, there were no significant effects other than nitrogen rate.

The student's guide is intended for foreign students choosing Soil science subject at UM. It contains the basics of the geological composition of the lithosphere, classification, mineral composition, and recognition of various rocks. Students are guided through the use of proper equipment and methods of sampling, transportation, preservation, and sample preparation prior to further analysis. Field work and laboratory procedures for determining various physical (soil structure, texture, bulk density, porosity, soil moisture, soil colour) and chemical (soil reaction, organic matter content, nitrogen, phosphorus, and potassium content) characteristics of soil quality are described. Finally, it helps students to describe the soil profile with an accurate description of the general soil horizons and the determination of the soil type.

AbstractKubiëna (1938) was the first to introduce the concept of fabric in soil micromorphology, so this term has been used in soil micromorphology for a long time. The term “fabric” was initially applied to rocks by geologists and petrologists. This type of fabric is defined as the “factor of the texture of a crystalline rock which depends on the relative sizes, the shapes, and the arrangement of the component crystals” (Matthews and Boyer 1976). This definition has been adapted for soil micromorphology and its latest definition has been given by Bullock et al. (1985) as: “soil fabric deals with the total organization of a soil, expressed by the spatial arrangement of the soil constituents (solid, liquid, and gaseous), their shape, size, and frequency, considered from a configurational, functional and genetic view-point”. In conclusion, the soil micromorphologist should consider the fabric as an arrangement and∕or organization of soil constituents.

Abstract Climate change and soil fertility decline are threatening food security in southern Africa and efforts have been made to adapt current cropping systems to the needs of smallholder farmers. Conservation Agriculture (CA) based on minimum soil disturbance, crop residue retention and crop diversification has been proposed as a strategy to address the challenges smallholder farmers face. Here we analyse the potential contributions of CA towards adaptation to the effects of climate change by summarizing data on infiltration, soil moisture dynamics and crop productivity under heat and drought stress. The data were taken in the main from CIMMYT's on-farm and on-station trial network. Data show that CA systems maintain 0.7-7.9 times higher water infiltration than the conventional tilled system depending on soil type, which increases soil moisture during the cropping season by 11%-31% between CA treatments and the conventional control treatment. This leads to greater adaptive capacity of CA systems during in-season dry spells and under heat stress. A supporting regional maize productivity assessment, analysing the results of numerous on-farm and on-station experiments, showed that CA systems will outperform conventional tillage practices (CP), especially on light-textured soils, under heat and drought stress. With higher rainfall and low heat stress, this relation was more positive towards CP and on clay soil there was no benefit of practising CA when rainfall was high. The long dry season and limited biomass production of CA systems in southern Africa require complementary good agricultural practices to increase other soil quality parameters (e.g. increased soil carbon) to maintain higher productivity and sustainability over time. This can be addressed by combinations of improved stress-tolerant seed, targeted fertilization, inclusion of tree-based components or green manure cover crops in the farming system, scale-appropriate mechanization and improved weed control strategies.

Soil texture can be defined as the size and proportion of the soil particles—sand, silt, and clay—that are present in a soil. . . . Sand is the largest—from 0.05 to 2mm—and considered coarse texture; consists of angular spheres or cubes. Silt is intermediate—from 0.002 to 0.05mm—and considered medium texture; consists of properties between sand and clay. Clay is the smallest, being less than 0.002mm, and considered fine texture; appears as plate-like or flakes. . . . Any individual soil can be placed on the soil textural diagram when relative amounts of sand, silt, and clay are specified. As a general rule, the type of soil can be determined by feel when squeezed between the fingers. If the soil feels harsh and gritty it would be classified as a sandy soil. One that feels smooth and not sticky or plastic would be a silt soil, and one that is sticky or plastic would be a clay. Another way to distinguish between soils is their ability to form a ribbon. Soils that will not form a ribbon are sands. Those that form a fragile ribbon are loams; those that easily form a thick ribbon are clay loams; and those that easily form a long, thin, flexible ribbon are clays. . . . To be classified a sand, the soil must have more than 45% sand. To be classified a clay, the soil must have more than 20% clay. Loam is a mixture of sand, silt, and clay in about equal proportions. It is considered “ideal” for growing plants. . . . Weight of the soil solids is called “particle density.” For most common mineral soils (soils in which organic matter is usually less than 20%), particle density is about 2.65 g/cm3. Organic soils (where organic matter is greater than 20%) are usually about half as heavy, with particle density between 1.1 to 1.4 g/cm3. This measurement would be an important factor to consider if much material was to be transported for topsoiling.

Minerals and organic matter comprise the solid phase of the soil. The geological origin of the soil minerals, and the input of organic matter from plants and ani­mals, are briefly discussed in section 1.2.1. A basic knowledge of the composition and properties of these materials is fundamental to understanding how a soil in­fluences the growth of grapevines. A striking feature of soil is the size range of the mineral matter, which varies from boulders (>600 mm diameter), to stones and gravel (600 to >2 mm diameter), to particles (<2 mm diameter)—the fine earth fraction. The fine earth fraction is the most important because of the type of miner­als present and their large surface areas. The ratio of surface area to volume de­fines the specific surface area of a particle. The smaller the size of an object, the larger is the ratio of its surface area to volume. This can be demonstrated by con­sidering spherical particles of radius 0.1 mm, 0.01 mm, and 0.001 mm (1 mi­crometer or micron, μm). The specific surface areas of these particles are 30, 300, and 3000 mm2/mm3, respectively. In practice, the specific surface area is mea­sured as the surface area per unit mass, which implies a constant particle density (usually taken as 2.65 Mg/m3). A large specific surface area means that more mol­ecules can be adsorbed on the surface. Representative values for the specific sur­face areas of sand, silt, and clay-size minerals are given in table 2.1. Note the large range in specific surface area, even for the clay minerals, from as little as 5 m2/g for kaolinite to 750 m2/g for Na-montmorillonite. Because specific surface areas are important, we need to know the size distri­bution of particles in the fine earth fraction. This is expressed as the soil’s texture. The types of minerals that make up the individual size fractions are also impor­tant because they too influence the reactivity of the surfaces. Both these topics are discussed here. All soils show a continuous distribution of particle sizes, called a frequency dis­tribution. This distribution relates the number (or mass) of particles of a given size to their actual size, measured by the diameter of an equivalent sphere.

In the natural world, plant species evolve and adapt to specific soil and climatic conditions. The productivity and stability of a natural soil-plant continuum or ecosystem are maintained through diversity, succession, and internal nutrient cycling. Hence, there are no rich soils or poor soils but different soils supporting different ecosystems. From an agricultural viewpoint, however, the term soil fertility may be defined as the capacity of a soil, under a given rainfall or water management regime, to support the growth of common food and fiber crops with minimum or no external inputs for a long period of time without adversely degrading the chemical, physical, and biological properties of the soil. Thus, a naturally fertile or productive soil usually possesses the following features: • good soil tilth or workability • adequate organic matter content in the surface layer • adequate permeability • adequate available water-holding capacity • slightly acidic to neutral pH • loamy-textured topsoil • moderate amounts of smectite and weatherable minerals Worldwide, the most fertile soils are prairie soils derived from glacial till, young alluvial soils in river valleys and deltas and high-base-status volcanic ash soils. These soils are also known as Mollisols, high-base-status Entisols and high-base- status Andisols, respectively, according to the Soil Taxonomy classification. At the other end of the scale are the so-called infertile soils. These are the highly weathered and strongly leached soils or “lateritic soils” of the tropics. Ultisols and Oxisols rich in kaolinite and Fe and Al oxides fall into this category. The soil fertility status of other types of soils falls in between these two groups. In general, parent material and stage of weathering are good indicators of soil fertility. Moderately weathered soils derived from basic parent rocks such as basalts and limestone and recent alluvial deposits are invariably more fertile than those derived from acidic parent rocks such as sandstone, quartzite, and coarse-grained granite. Strongly weathered soils generally have a low fertility because primary minerals containing plant nutrients such as Ca, Mg, and K have long disappeared through dissolution, acidification, and leaching. The dominant clay-size minerals in strongly weathered soils, kaolinite and Fe and Al oxides, possess little capacity to retain these cations.

One of the great challenges of the environmental diagnoses of soils contaminated with hydrocarbons is the optimization of analytical determinations. For this reason, this chapter evaluates the extraction of hydrocarbons by the Soxhlet method through the design of experiments (DOE), variating three different solvents, three soils, and three extraction times. Soil was experimentally contaminated at different concentrations, and hydrocarbons totals relying on conditions organic matter, electrical conductivity, pH and textures, amount of sample, solvents, and NaSO4, were studied. The variables were evaluated by means of an analysis of the Taguchi design and a factorial design, with the results the significant and optimal parameters of the process were determined, which were solvent type and time (10 hours and dielectric constant of 9). Also, the model discards the soil properties. These results will save time and resources, and they reduce errors.

The disturbance regime of an ecosystem consists of a number of different types of disturbance agents operating over a range of spatial and temporal scales (Pickett and White, 1985). Each type of disturbance has its own set of characteristics, including size, frequency of occurrence, intensity, and attributes associated with location, including soil texture, topographic position, and grazing intensity by cattle. These characteristics result in different short-term localized effects on ecosystems as well as long-term broad-scale effects as the disturbances accumulate through time. Disturbance effects occur at multiple levels of organization, from individuals to populations, communities, and the ecosystem. Effects of disturbance can also vary for different types of organisms or processes associated with plants, animals, and soils. Understanding interactions among the characteristics of a disturbance and the properties associated with the response variable is key to understanding and predicting recovery patterns through time and space. Although successional studies have been conducted in grasslands for more than a century, our understanding of the roles of different kinds of disturbances in generating and maintaining patterns in vegetation and in determining species dominance in shortgrass ecosystems has developed only since the 1980s. Referred to as gap dynamics, our current view of the role of disturbance is a dynamic one, in which the recovery of vegetation depends upon interactions among disturbance characteristics and the life history traits of plants. This gap dynamics conceptualization provides an alternative view of vegetation dynamics compared with traditional successional models based on Clements (1916, 1928). Much of the recent work on disturbances in the shortgrass steppe focuses on the relationships between disturbance characteristics and plant life history traits to test the different Clementsian-based models. Most successional studies of shortgrass communities prior to the 1980s focused on recovery after large-scale disturbances and, in particular, cultivation and subsequent abandonment of agricultural 1 elds (Costello, 1944; Judd, 1974; Judd and Jackson, 1939; Savage and Runyon, 1937). The earliest studies were based upon a Clementsian model (Clements, 1916, 1928) that formed the t raditional v iew of succession in these communities (Fig. 6.1). This model predicted that shortgrasses would dominate cover within 25 to 50 years after abandonment.

Soils are weathering products of rocks and minerals. The rocks in Earth’s outer surface can be classified as igneous, sedimentary, or metamorphic rocks. Igneous rocks are formed from molten magma. They are composed of primary minerals, which are minerals that have not been altered chemically since they formed as molten lava solidified. Examples of primary minerals are the light-colored minerals quartz, muscovite, feldspars, and orthoclase, and the dark-colored minerals biotite, augite, and hornblende. In general, dark-colored minerals contain iron (Fe) and magnesium (Mg) and are more easily weathered than light-colored minerals. Coarse-grained igneous rocks, such as granite and diorite, contain mainly lightcolored minerals, while medium-grained igneous rocks such as gabbro, peridotite, and hornblendite are composed of dark-colored primary minerals. Rhyolite and andesite are medium-grained igneous rocks containing light-colored primary minerals. Basalt is dark-colored with an intermediate to fine rock texture, and basaltic volcanic glass has a fine texture. Examples of light-colored igneous rocks with a fine texture are felsite and obsidian. Sedimentary rocks are the most common type of rock, covering about 75% of Earth’s land surface. They are mainly composed of secondary minerals, which are minerals that are recrystallized products of the chemical breakdown and/or alteration of primary minerals. Sedimentary rocks form when weathering products from rocks are cemented or compacted. For example, quartz (SiO2) sand, a weathering product of granite, may become cemented into sandstone. Another common sedimentary rock is limestone. There are two types of limestone, namely, calcite (CaCO3), and dolomite (CaCO3.MgCO3). Clays may become cemented into a sedimentary rock, which is known as shale. A sedimentary rock with several dominant minerals is called a conglomerate, in which small stones with different mineralogy are cemented together. Metamorphic rocks are formed by the metamorphism of igneous or sedimentary rocks. Great pressure and high temperatures, caused by the shifting of continental plates, can compress, distort, and/or partially re-melt the original rocks. Igneous rocks are commonly modified to form schist and gneiss, in which light and dark minerals have been reoriented into bands. Sedimentary rocks, such as limestone and shale, may be metamorphosed to form marble and slate, respectively.

At the Pine Ridge winery in Napa Valley, California, a sign lists six essential steps in wine production. The first step reads . . . Determine the site—prepare the land, terrace the slopes for erosion control, provide drainage and manage soil biodiversity. . . . Determining the site means gathering comprehensive data on the local cli­mate, topography, and geology, as well as the main soil types and their distribu­tion. Traditionally, site determination was done using the knowledge and experi­ence of individuals. Now it is possible to combine an expert’s knowledge with digital data on climate, parent material, topography, and soils in a GIS format to assess the biophysical suitability of land for wine grapes. Viticultural and soil ex­perts together identify the key properties and assign weightings to these proper­ties. An example of an Analytical Hierarchy Process is shown in figure 8.1. In this approach, both objective and subjective data were pooled and evaluated to decide the suitability of land for viticulture in West Gippsland, Victoria. In this region with a relatively uniform, mild climate, soil was given a 70% weighting, and the important soil properties were identified as depth, drainage, sodicity, texture, and pH. But in other areas, with another group of experts, a different set of key prop­erties and weightings may well be identified. For example, a similar approach used in Virginia, in the United States, gave only a 25% weighting to soil and 30% to elevation (which affected temperature, a critical factor governing growth rate and ripening) (Boyer and Wolf 2000). This kind of approach can be refined to indicate site suitability for a partic­ular variety within a region of given macroclimate. For example, Barbeau et al. (1998) assessed the suitability of sites in the Loire Valley, France, for the cultivar Cabernet Franc, using an index of “precocity.” Such an index is related to the ability of the fruit to accumulate sugar and anthocyanins and to attain a favorable acidity.

Изучение гранулометрического состава почв Ханкайского заповедника показало, что профили почв представляют собой многослойные спектры различного литологического сложения. Сложность почвенных профилей по гранулометрическому составу определяется степенью проявления поемного и аллювиального процессов, литологическими особенностями почвообразующего материала. По типу сложения выделено несколько литологических групп. Темно-гумусовые глеевые, аллювиальные луговые глеевые почвы и буроземы глееватые отличаются резкой дифференциацией профиля по гранулометрическому составу на верхнюю легкую и нижнюю глинистую толщу. Для этих почв отмечено наибольшее содержание фракций физической глины и ила по всему почвенному профилю. Буроземы типичные и аллювиальные луговые глееватые, вышедшие из зоны затопления, характеризуются литологически однородным легким составом. В этих почвах выявлено высокое содержание фракций мелкого песка. The soil profiles the Khankaiskiy Nature Reserve represent multilayer spectra of various lithological addition. The complexity of soil profiles in terms of particle-size distribution is determined by the degree of manifestation of soil and alluvial processes, lithological features of soil-forming material. Several lithological groups are distinguished by the type of texture. Dark humus gley, alluvial meadow gley soils and burozem gleyic shrouds are distinguished by a sharp differentiation of the profile by granulometric composition into an upper light and lower clay thickness. The largest content of fractions of physical clay and silt was noted throughout the profiles for these soils. Burozem typical and alluvial meadow gleyic soils that have emerged from the flood zone characterize this with a lithologically homogeneous light composition. A high content of fine sand fractions was revealed in these soils.

Small leaks caused by external pitting corrosion are the leading cause of failure in oil and gas pipelines in many regions of Mexico. Because of this, the need for realistic and reliable pitting corrosion growth models that are capable of accounting for the chemical and physical properties of soils and pipeline coatings is especially great. In this work, maximum pit depths and soil and coating data that were gathered at excavation sites across southern Mexico are used to investigate the impact of soil and pipe characteristics on pitting corrosion in buried pipelines. Soil field-measurements included resistivity, pH, pipe-to-soil potential, humidity, chloride, bicarbonate and sulphate levels, redox potential, soil texture and coating type. Together with the local physical chemistry of the soil and the coating characteristics, the maximum pit depth and pipeline’s age were recorded at more than 250 dig sites. The time dependence of the maximum pit depth was modeled as ymax = β(t−t0)α, with β and α being positive constants, t being the pipe’s age and t0 the pit initiation time. A multivariate regression analysis was conducted with ymax as the dependent variable, while the pipeline’ age and the soil and pipe properties were used as the independent variables. The optimal dependence of β and α on these variables was found and predictive models were proposed to describe the time dependence of the average maximum pit depth and growth rate on soil and pipe properties. Besides the creation of a generic model fitted to all the gathered data, a model was proposed for each one of the three soil types identified in this study: clay, clay-loam and sandy-clay-loam. It is shown that the application of the proposed model allows for prediction of corrosion pit growth more accurately than previous models and that this improvement positively impacts on integrity management plans that address the threat posed by external pitting corrosion.

External pitting corrosion constitutes the degradation mechanism responsible for about 66% of the incidents reported in the last decade for oil and gas pipelines in Mexico. Thus, major efforts are underway to improve the characterization and modeling of pitting corrosion of buried pipelines. Special attention is devoted to estimate the average corrosion rate and corrosion rate variance because they are the key parameters in the estimation of the trend in pipeline reliability. This work presents the results of field and simulation studies in which soil and pipe data were gathered together with the maximum depth of external corrosion pits found at more than 250 excavation sites across southern Mexico. The distributions of parameters such as chloride, bicarbonate and sulfate levels, resistivity, pH, pipe/soil potential, humidity, redox potential, soil texture and coating type have been used to predict the distribution of pitting corrosion rate of pipelines in contact with clay, clay-loam and sandy-clay-loam soils. The time dependence of the pitting corrosion rate was fitted to a power law through a multivariate regression analysis with the maximum pit depth as the dependent variable and the pipeline age and the soil and coating properties as the independent variables. Monte Carlo simulations were conducted in which random values drawn from the distributions fitted to the field data were used to evaluate the power law model proposed for the corrosion rate. For each soil type, the distribution that best fitted the corrosion rate data was found. The results of this study will provide reliability analysts with a more accurate description of the growth rate of external corrosion pits. It is expected that this information will positively impact on integrity management plans addressing the threat posed by this damage mechanism.

Landscape change has been extensively documented throughout rural Europe over the past decades. The dominating tendencies are intensification of agriculture and land marginalization. In territories of former USSR radical land use changes have shattered rural landscape structure throughout the 20th century, which in many cases have led to land marginalization in form of abandonment of agricultural lands and subsequent uncontrolled afforestation. This process is especially evident in mosaic type landscapes – landscapes of small intertwining structure of patches of agricultural land and forests. The paper presents the results of the study based on application of multinomial logistic regression and cross-analysis using binary logistic regression in R of important physical factors of landscape structure such as land quality, soil texture, slope, as well as land use patch size. Additionally certain human induced factors such as distance to closest paved road, cadastral plot size and availability of Single Area Payments are added for more accurate assessment of the driving forces of landscape change and possible vectors for supplementary studies. Data was gathered in intensive field surveys combined with analysis of high quality remotely sensed data. Results show strong interrelationship of several analyzed factors and thus calls for attention to further development of methodology.

It is generally believed that physical and chemical condition of the pipeline environment (such as soil texture, drainage, ground topography, cathodic protection level, pH, etc) in addition to pipeline construction factors (such as pipe vs. ground slope, type and quality of the pipe coating, etc.) affect the incidence and severity of external corrosion and SCC on pipelines. In an attempt to identify locations of highest susceptibility to external corrosion and cracking on a tape coated Enbridge pipeline, and to aid integrity management processes; Enbridge embarked on a project investigating landscape factors which might affect the severity of external corrosion and stress corrosion cracking (SCC) on the pipeline. Results showed that some of the investigated factors had positive correlations with the severity of external corrosion and SCC on the tape coated pipeline. However, despite the positive correlations observed, they were not strong enough to be used as an independent predictive tool.

Agricultural production is one of the main sources of nitrogen and phosphorous inputs to the water bodies. Quantifying nutrient input from agriculture is needed both to develop effective environmental measures and to justify the technologies to be applied with due account for local natural and climatic conditions. Several related national studies have been conducted since 2015. Institute for Engineering and Environmental Problems in Agricultural Production (IEEP) methodology was used for this purpose. It determines the nitrogen and phosphorus content in the arable layer, including N and P amounts applied with mineral and organic fertilisers. Such factors as soil type and texture, the distance to the water bodies and the land use structure are used to estimate the nutrient input to the water bodies. In addition, the consistency of manure handling technologies with Best Available Techniques (BAT) principles is taken into account through introduction of relevant coefficients. Calculation results according to IEEP methodology were used in the follow-up general assessment of the nutrient load on the water bodies from different sources with the use of Institute of Limnology Load Model. Satisfactory correspondence between the assessment results and the values calculated using the monitoring data confirmed the adequacy of the above assessment procedure. Following its outcomes, the nutrient reduction potential of agricultural sources is approximately 10–20 %.

The Textile Industry is one of the most representative industries in the world's industrial structure and has always assumed an important role in the national economy. Globally, and according to a study by Grand View Research, this industry represented 961.5 billion dollars in 2019 (Grand View Research - Global textile market 2020-2027).However, this sector represents the second most polluting industry in the world, and the environmental impacts occur, above all, in terms of water consumption, soil erosion, CO2 emissions and the resulting residues.The textile industry is responsible for the production of 2.1 billion tons of waste, most of which are discarded into the water ecosystem, essentially during the dyeing processes. In fact, dyeing is one of the most polluting processes in the textile industry, representing a high source of pollution of water circuits and environmental ecosystem. According to the World Bank, textile dyeing industries are responsible for 20% of industrial water pollution.This reality acquires even greater proportion when analyzing the quantities of dyes produced. Every year, it is estimated that around 10,000 types of dyes and pigments, and 7x105 tons of synthetic dyes are produced in the market, for this sector. From this production, more than 200,000 tons of dyes are released into industrial effluents during the textile processing phases (dyeing and finishing).To reduce the environmental footprint caused by the textile industry, the replacement of synthetic dyes by others from natural compounds has been the subject of extensive research, through the development of new ways of coloring textile materials.One of the emerging research areas is related to the exploration of obtaining natural dyes, from microorganisms, called Biodyes.The research aims to develop a sustainable dyeing process, through the production of biodyes, from the metabolic study of the production of microorganisms.It is known the potential that exists in the generation of color and a wide spectrum of functionalities, from biotechnology, regarding the metabolic pathway of certain microorganisms, in the specific case from bacteria such as E. Coli. The main advantages of the innovation proposed in the investigation of this research work are compared to synthetic dyes/pigments, its very low environmental impact, in terms of consumption of material and energy resources, environmental pollution and non-toxicity of the resulting effluents. At the same time, the production of dyes from microorganisms, bacteria and/or fungi, has benefits compared to natural alternatives of plant origin due to its independence from seasonal limitations and climatic conditions, as well as the rapid growth of some substances and therefore with much higher biological yields and consequent industrial application.

In recent years, a large number of nano-size semiconductors have been investigated for their potential applications in photovoltaic cells, optical sensor devices, and photocatalysts [1, 2, 3]. Nano-size semiconductor particles have many interesting properties due mainly to their size-dependent electronic and optical properties. Appropriately, many speciality of nanomaterials such as CdS and ZnS semiconductor particles, and other metal oxides such as ZnO and lithium-titanate oxide (LTO) have been prepared. However, most of them were prepared with toxic reactants and/or complex multistep reaction processes. Particularly, it is quite difficult to produce LTO nanoparticles, since it typically requires wearisome conditions such as very high temperature over 1000 °C, long producing times, and so on. To overcome such problems, various core/shell type nanocrystals were prepared through different methods such as the hydrothermal synthetic method, microwave, and sonochemistry. Also many coating methods on inorganic oxide nanoparticles were tried for the preparations of various core-shell type nanocrystals. Sonoluminescence (SL) is a light emission phenomenon associated with the catastrophic collapse of a gas bubble oscillating under an ultrasonic field [4]. Light emission of single bubble sonoluminescence (SBSL) is characterized by picosecond flashes of the broad band spectrum extending to the ultraviolet [5, 6]. The bubble wall acceleration has been found to exceed 1011 g at the moment of bubble collapse. Recently observed results of the peak temperature and pressure from the sonoluminescing gas bubble in sulfuric acid solutions [9] were accurately predicted by the hydrodynamic theory for sonoluminescence phenomena [7, 10, 11, 12], which provides a clue for understanding sonochemical reactions inside the bubble and liquid layer adjacent to the bubble wall. Sonochemistry involves an application of sonoluminescence. The intense local heating and high pressure inside the bubbles and liquid adjacent bubble wall from such collapse can give rise to unusual effects in chemical reactions. The estimated temperature and pressure in the liquid zone around the collapsing bubble with equilibrium radius 5 μm, an average radius of bubbles generated in a sonochemical reactor at a driving frequency of 20 kHz with an input power of 179 W, is about 1000 °C and 500 atm, respectively. At the proper condition, a lot of transient bubbles are generated and collapse synchronistically to emit blue light when high power ultrasound is applied to liquid, and it is called multibubble sonoluminescence (MBSL). Figure 1 shows an experimental apparatus for MBSL with a cylindrical quartz cell, into which a 5 mm diameter titanium horn (Misonix XL2020, USA) is inserted [13]. The MBSL facilitates the transient supercritical state [14].in the liquid layer where rapid chemical reactions can take place. In fact, methylene blue (MB), which is one of a number of typical textile dyestuffs, was degraded very fast at the MBSL condition while MB does not degrade under simple ultrasonic irradiation [13]. MBSL has been proven to be a useful technique to make novel materials with unusual properties. In our study, various metal oxides such as ZnO powder [15], used as a primary reinforcing filler for elastomer, homogeneous Li4Ti5O12 nanoparticles [16], used for electrode materials, and core/shell nanoparticles such as CdS coating on TiO2 nanoparticles [17] and ZnS coating on TiO2 nanoparticles [18], which are very likely to be useful for the development of inorganic dye-sensitized solar cells, were synthesized through a one pot reaction under the MBSL condition. Figure 2 shows the XRD pattern of ZnO nanoparticles synthesized from zinc acetate dehydrate (Zn(CH3CO2)2 · 2H2O, 99.999%, Aldrich) in various alcohol solutions with sodium hydroxide (NaOH, 99.99%, Aldrich) at the MBSL condition. The XRD patterns of all powers indicate hexagonal zincite. The XRD pattern for the ZnO nanoparticles synthesized is similar to the ZnO powder produced by a modified sol-gel process and subsequent heat treatment at about 600 °C [19] as shown in Fig.3. The average particle diameter of ZnO powder is about 7 nm. A simple sonochemical method for producing homogeneous LTO nanoparticles, as shown schematically in Fig. 4. First, LiOH and TiO2 nanoparticles were used to prepare LiOH-coated TiO2 nanoparticles as shown in Fig.5. Second, the resulting nanoparticles were thermally treated at 500 °C for 1 hour to prepare LTO nanoparticles. Figure 6 shows a high resolution transmission electron microscope image of LTO nanoparticles having an average grain size of 30–40 nm. All the nanoparticle synthesized are very pure in phase and quite homogeneous in their size and shape. Recently we succeeded in synthesizing a supported nickel catalyst such as Ni/Al2sO3, MgO/Al2O3 and LaAlO3, which turned out to be effective for methane decomposition [20]. Sonochemistry may provide a new way to more rapidly synthesize many specialty nanoparticles with less waste [21]. This clean technology enables the preparation of new materials such as colloids, amorphous particles [22], and various alloys.

Cette étude porte sur une des innovations contemporaines liées à l’économie de la publication scientifique : les accords dits transformants, un objet relativement circonscrit au sein des relations entre consortiums de bibliothèques et éditeurs scientifiques, et temporellement situé entre 2015 et 2020. Ce type d’accords a pour objectif affiché d’organiser la transition du modèle traditionnel de l’abonnement à des revues (souvent proposées par regroupements thématiques ou collections) vers celui de l’accès ouvert en opérant une réaffectation des budgets qui y sont consacrés. Notre travail d’analyse sociologique constitue une première étude systématique de cet objet, fondée sur la recension de 197 accords. Le corpus ainsi constitué inclut des accords caractérisés par la coprésence d’une composante d’abonnement et d’une composante de publication en accès ouvert, même minimale (« jetons » de publication offerts, réduction sur les APC...). En conséquence, ont été exclus de l’analyse les accords portant uniquement sur du financement centralisé de publication en accès ouvert, que ce soit avec des éditeurs ne proposant que des revues avec paiement par l’auteur (PLOS, Frontiers, MDPI...) ou des éditeurs dont une partie du catalogue est constitué de revues en accès ouvert. L’accord le plus ancien de notre corpus a été signé en 2010, les plus récents en 2020 – les accords ne commençant qu’en 2021, même annoncés au cours de l’étude, n’ont pas été retenus. Plusieurs résultats se dégagent de notre analyse. Tout d’abord, on note une grande diversité des acteurs impliqués avec 22 pays et 39 éditeurs, même si certains consortiums (Pays-Bas, Suède, Autriche, Allemagne) et éditeurs (CUP, Elsevier, RSC, Springer) en ont signé beaucoup plus que d’autres. Ensuite, la durée des accords, comprise entre une et six années, révèle une distribution très inégalitaire, avec plus de la moitié des accords (103) signés pour 3 ans, ainsi qu’une faible proportion pour 4 ans ou plus (22 accords). Enfin, en dépit d’appels répétés à la transparence, moins de la moitié des accords (96) ont un texte accessible au moment de cette étude, sans qu’on puisse observer une tendance récente à une plus grande disponibilité. L’analyse montre également des degrés d’ouverture très variables, allant d’une simple information sur le répertoire ESAC en passant par la mise à disposition d’un format annotable jusqu’à l’attribution d’un DOI et d’une licence de réutilisation (CC-BY), en incluant le détail des sommes monétaires. Parmi les 96 accords disponibles, dont 47 signés en 2020, 62 ont fait l’objet d’une analyse en profondeur. C’est à notre connaissance la première analyse à cette échelle, sur un type de matériel non seulement inédit, mais qui était auparavant soumis à des clauses de confidentialité. Fondée sur une lecture minutieuse, l’étude décrit de manière fine leurs propriétés, depuis la matérialité du document jusqu’aux formules financières, en passant par leur morphologie et l’ensemble des droits et devoirs des parties. Les contenus des accords sont donc analysés comme une collection dont nous cherchons à déterminer les points communs et les variations, à travers des codages explicites sur certaines de leurs caractéristiques. L’étude pointe également des incertitudes, et notamment leur caractère « transitionnel », qui demeure fortement discuté. D’un point de vue morphologique, les accords montrent une grande diversité en matière de taille (de 7 à 488 pages) et de structure. Néanmoins, par définition, ils articulent tous deux objets essentiels : d’une part, les conditions de réalisation d’une lecture d’articles de revues, sous forme d’abonnement, mêlant des préoccupations d’accès et de sécurité ; d’autre part, les modalités de publication en accès ouvert, articulant la gestion d’un nouveau type de workflow à toute une série d’options possibles. Parmi ces options, mentionnons notamment le périmètre des revues considérées (hybrides et/ou accès ouvert), les licences disponibles, le degré d’obligation de cette publication, les auteurs éligibles ou le volume d’articles publiables. L’un des résultats les plus importants de cette analyse approfondie est la mise au jour d’un découplage presque complet, au sein même des accords, entre l’objet abonnement et l’objet publication. Bien entendu, l’abonnement est systématiquement configuré dans un monde fermé, soumis à paiement qui déclenche des séries d’identification des circulations légitimes tant du contenu informationnel que des usagers. Il insiste notamment sur les interdictions de réutilisation ou même de copie des articles scientifiques. À l’opposé, la publication en accès ouvert est attachée à un monde régi par l’accès gratuit au contenu, ce qui induit des préoccupations de gestion du workflow et des modalités d’accessibilité. De plus, les différents éléments constitutifs de ces objets contractuels ne sont pas couplés : d’un côté, les lecteurs sont constitués de l’ensemble des membres des institutions abonnées, de l’autre, seuls les auteurs correspondants (« corresponding authors ») sont concernés ; les listes de revues accessibles à la lecture et celles réservées à la publication en accès ouvert sont le plus souvent distinctes ; les workflows ont des objectifs et des organisations matérielles totalement différentes, etc. L’articulation entre les deux objets contractuels relève uniquement d’une formule de distribution financière qui, outre des combinaisons particulières entre l’un et l’autre, permet d’attribuer des étiquettes distinctes aux accords (offset agreement, publish & read, read & publish, read & free articles, read & discount). Au-delà de cette distribution, l’étude des arrangements financiers montre une gamme de dispositions allant d’une prévisibilité budgétaire totale, donc identique aux accords d’abonnement antérieurs, à une incertitude sur le volume de publication ou sur le montant définitif des sommes échangées. Les modalités concrètes de calcul des montants associés à la publication en accès ouvert sont relativement variées. S’il existe effectivement des formules récurrentes (volume d’articles multiplié par un prix individuel, reprise de la moyenne des sommes totales d’APC des années précédentes...), le calcul des sommes en jeu est toujours le résultat d’une négociation singulière entre un consortium et un éditeur scientifique, et aboutit parfois à des formules originales et complexes. À ce titre, l’espace des possibles en matière de formules financières n’est jamais totalement clos. Par ailleurs, la volonté des consortiums d’opérer une « transformation » de leurs accords vers la publication à coût constant renvoie à des définitions diversifiées du « coût » (inclusion ou non des dépenses d’APC préexistantes) et de la constance (admission ou pas d’une « inflation » à 2 ou 3%). De plus, nous n’avons observé aucune disposition contractuelle permettant d’anticiper les sommes en jeu au-delà de l’horizon temporel de l’accord courant. La grande diversité des accords provient d’une part des conditions initiales des relations entre consortiums et éditeurs scientifiques – les sommes dépensées en abonnement étant le point de départ des nouveaux accords –, d’autre part des objectifs de chaque partie. Même si cette étude excluait volontairement les négociations, les accords portent des traces de ces objectifs. Ainsi, de nombreux accords sont de nature explicitement expérimentale, quand certains visent un contrôle budgétaire strict, ou d’autres ambitionnent, dans la période plus récente, la publication du plus grand nombre possible d’articles en accès ouvert. C’est dans ce dernier cas qu’on touche à l’ambiguïté des attentes générales sur les accords transformants. En effet, pour les consortiums, la dimension « transformante » consiste essentiellement à transférer les sommes traditionnellement allouées à l’abonnement vers la publication en accès ouvert. Mais l’objectif n’est jamais de transformer le modèle économique des revues, c'est-à-dire de faire basculer des revues sous abonnement ou hybrides en revues entièrement en accès ouvert. D’ailleurs, aucune clause ne vise une telle fin – à l’exception du modèle d’accord proposé par l’éditeur ACM. Du côté des éditeurs, et notamment de Springer, le caractère cumulatif des accords nationaux passés vise à projeter un monde de la publication où l’accès ouvert devient de fait quantitativement très dominant, sans pour autant modifier de manière pérenne le modèle économique de leurs revues. Notre étude montre que les accords transformants actuels ne permettent pas d’assurer de manière durable une transition de l’économie de la publication vers l’accès ouvert, dans la mesure où ils n’offrent pas de garantie sur le contrôle des dépenses ni sur la pérennité de l’ouverture des contenus. L’avenir des relations entre consortium et éditeur demeure largement indéterminé.Cette étude porte sur une des innovations contemporaines liées à l’économie de la publication scientifique : les accords dits transformants, un objet relativement circonscrit au sein des relations entre consortiums de bibliothèques et éditeurs scientifiques, et temporellement situé entre 2015 et 2020. Ce type d’accords a pour objectif affiché d’organiser la transition du modèle traditionnel de l’abonnement à des revues (souvent proposées par regroupements thématiques ou collections) vers celui de l’accès ouvert en opérant une réaffectation des budgets qui y sont consacrés. Notre travail d’analyse sociologique constitue une première étude systématique de cet objet, fondée sur la recension de 197 accords. Le corpus ainsi constitué inclut des accords caractérisés par la coprésence d’une composante d’abonnement et d’une composante de publication en accès ouvert, même minimale (« jetons » de publication offerts, réduction sur les APC...). En conséquence, ont été exclus de l’analyse les accords portant uniquement sur du financement centralisé de publication en accès ouvert, que ce soit avec des éditeurs ne proposant que des revues avec paiement par l’auteur (PLOS, Frontiers, MDPI...) ou des éditeurs dont une partie du catalogue est constitué de revues en accès ouvert. L’accord le plus ancien de notre corpus a été signé en 2010, les plus récents en 2020 – les accords ne commençant qu’en 2021, même annoncés au cours de l’étude, n’ont pas été retenus. Plusieurs résultats se dégagent de notre analyse. Tout d’abord, on note une grande diversité des acteurs impliqués avec 22 pays et 39 éditeurs, même si certains consortiums (Pays-Bas, Suède, Autriche, Allemagne) et éditeurs (CUP, Elsevier, RSC, Springer) en ont signé beaucoup plus que d’autres. Ensuite, la durée des accords, comprise entre une et six années, révèle une distribution très inégalitaire, avec plus de la moitié des accords (103) signés pour 3 ans, ainsi qu’une faible proportion pour 4 ans ou plus (22 accords). Enfin, en dépit d’appels répétés à la transparence, moins de la moitié des accords (96) ont un texte accessible au moment de cette étude, sans qu’on puisse observer une tendance récente à une plus grande disponibilité. L’analyse montre également des degrés d’ouverture très variables, allant d’une simple information sur le répertoire ESAC en passant par la mise à disposition d’un format annotable jusqu’à l’attribution d’un DOI et d’une licence de réutilisation (CC-BY), en incluant le détail des sommes monétaires. Parmi les 96 accords disponibles, dont 47 signés en 2020, 62 ont fait l’objet d’une analyse en profondeur. C’est à notre connaissance la première analyse à cette échelle, sur un type de matériel non seulement inédit, mais qui était auparavant soumis à des clauses de confidentialité. Fondée sur une lecture minutieuse, l’étude décrit de manière fine leurs propriétés, depuis la matérialité du document jusqu’aux formules financières, en passant par leur morphologie et l’ensemble des droits et devoirs des parties. Les contenus des accords sont donc analysés comme une collection dont nous cherchons à déterminer les points communs et les variations, à travers des codages explicites sur certaines de leurs caractéristiques. L’étude pointe également des incertitudes, et notamment leur caractère « transitionnel », qui demeure fortement discuté. D’un point de vue morphologique, les accords montrent une grande diversité en matière de taille (de 7 à 488 pages) et de structure. Néanmoins, par définition, ils articulent tous deux objets essentiels : d’une part, les conditions de réalisation d’une lecture d’articles de revues, sous forme d’abonnement, mêlant des préoccupations d’accès et de sécurité ; d’autre part, les modalités de publication en accès ouvert, articulant la gestion d’un nouveau type de workflow à toute une série d’options possibles. Parmi ces options, mentionnons notamment le périmètre des revues considérées (hybrides et/ou accès ouvert), les licences disponibles, le degré d’obligation de cette publication, les auteurs éligibles ou le volume d’articles publiables. L’un des résultats les plus importants de cette analyse approfondie est la mise au jour d’un découplage presque complet, au sein même des accords, entre l’objet abonnement et l’objet publication. Bien entendu, l’abonnement est systématiquement configuré dans un monde fermé, soumis à paiement qui déclenche des séries d’identification des circulations légitimes tant du contenu informationnel que des usagers. Il insiste notamment sur les interdictions de réutilisation ou même de copie des articles scientifiques. À l’opposé, la publication en accès ouvert est attachée à un monde régi par l’accès gratuit au contenu, ce qui induit des préoccupations de gestion du workflow et des modalités d’accessibilité. De plus, les différents éléments constitutifs de ces objets contractuels ne sont pas couplés : d’un côté, les lecteurs sont constitués de l’ensemble des membres des institutions abonnées, de l’autre, seuls les auteurs correspondants (« corresponding authors ») sont concernés ; les listes de revues accessibles à la lecture et celles réservées à la publication en accès ouvert sont le plus souvent distinctes ; les workflows ont des objectifs et des organisations matérielles totalement différentes, etc. L’articulation entre les deux objets contractuels relève uniquement d’une formule de distribution financière qui, outre des combinaisons particulières entre l’un et l’autre, permet d’attribuer des étiquettes distinctes aux accords (offset agreement, publish & read, read & publish, read & free articles, read & discount). Au-delà de cette distribution, l’étude des arrangements financiers montre une gamme de dispositions allant d’une prévisibilité budgétaire totale, donc identique aux accords d’abonnement antérieurs, à une incertitude sur le volume de publication ou sur le montant définitif des sommes échangées. Les modalités concrètes de calcul des montants associés à la publication en accès ouvert sont relativement variées. S’il existe effectivement des formules récurrentes (volume d’articles multiplié par un prix individuel, reprise de la moyenne des sommes totales d’APC des années précédentes...), le calcul des sommes en jeu est toujours le résultat d’une négociation singulière entre un consortium et un éditeur scientifique, et aboutit parfois à des formules originales et complexes. À ce titre, l’espace des possibles en matière de formules financières n’est jamais totalement clos. Par ailleurs, la volonté des consortiums d’opérer une « transformation » de leurs accords vers la publication à coût constant renvoie à des définitions diversifiées du « coût » (inclusion ou non des dépenses d’APC préexistantes) et de la constance (admission ou pas d’une « inflation » à 2 ou 3%). De plus, nous n’avons observé aucune disposition contractuelle permettant d’anticiper les sommes en jeu au-delà de l’horizon temporel de l’accord courant. La grande diversité des accords provient d’une part des conditions initiales des relations entre consortiums et éditeurs scientifiques – les sommes dépensées en abonnement étant le point de départ des nouveaux accords –, d’autre part des objectifs de chaque partie. Même si cette étude excluait volontairement les négociations, les accords portent des traces de ces objectifs. Ainsi, de nombreux accords sont de nature explicitement expérimentale, quand certains visent un contrôle budgétaire strict, ou d’autres ambitionnent, dans la période plus récente, la publication du plus grand nombre possible d’articles en accès ouvert. C’est dans ce dernier cas qu’on touche à l’ambiguïté des attentes générales sur les accords transformants. En effet, pour les consortiums, la dimension « transformante » consiste essentiellement à transférer les sommes traditionnellement allouées à l’abonnement vers la publication en accès ouvert. Mais l’objectif n’est jamais de transformer le modèle économique des revues, c'est-à-dire de faire basculer des revues sous abonnement ou hybrides en revues entièrement en accès ouvert. D’ailleurs, aucune clause ne vise une telle fin – à l’exception du modèle d’accord proposé par l’éditeur ACM. Du côté des éditeurs, et notamment de Springer, le caractère cumulatif des accords nationaux passés vise à projeter un monde de la publication où l’accès ouvert devient de fait quantitativement très dominant, sans pour autant modifier de manière pérenne le modèle économique de leurs revues. Notre étude montre que les accords transformants actuels ne permettent pas d’assurer de manière durable une transition de l’économie de la publication vers l’accès ouvert, dans la mesure où ils n’offrent pas de garantie sur le contrôle des dépenses ni sur la pérennité de l’ouverture des contenus. L’avenir des relations entre consortium et éditeur demeure largement indéterminé.