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The agricultural frontier in the Semi-arid Pampas Region of Argentina has expanded into marginal environments, resulting in the current reactivation of wind erosion hotspots and desertification processes. Zoning based on soil quality indicators (SQI) reveals differences in soil degradation. The aim of this study was to define zones based on the susceptibility of sandy soils to wind erosion in a 1,4 million hectare plain in the Pampa Medanosa at the south of Cordoba province, Argentina. Soil quality indicators related to wind erosion (erodible fraction (FE), organic carbon (CO) and clay and silt contents, and dry structural stability) were analyzed in samples from 0-5 cm depth at 283 sites. Spatial principal component analysis (PCA) and cluster analysis were performed to group sites with similar characteristics and define subregions based on erosion susceptibility. Four subregions (SR) with different susceptibility were identified: SR-I, with the highest potential wind erosion rate (EEP) (65 t. ha-1. year-1), the lowest CO values (10.95 g.kg-1), and the highest FE, 41%, which is above the permissible threshold (40%); SR-II, the largest in extension, with an EEP of 51 t. ha-1. year-1, showed a FE of 36% and 12.47 g.kg-1 of CO; SR-III, with an EEP of 35 t. ha-1. year-1, 31% FE, and 13 g.kg-1 of CO; SR-VI, with an EEP of 20 t. ha-1. year-1, 30% more CO than SR-I, 14.26 g.kg-1, and a FE of 27%. The results have allowed understanding that the Pampa Medanosa is a heterogeneous region where it is necessary to implement wind erosion mitigation techniques and respect the soil's potential use in each subregion to achieve sustainable agricultural production systems. [ABSTRACT FROM AUTHOR]

The central objective lies in synthesizing the use of cc and land by tourists and service providers. The methodology used was analytical of the information obtained in the cabinet and enriched with field work on the island of La Roqueta in Acapulco de Juárez, Guerrero, Mexico during the Easter and summer vacation periods from 2020 to August 2022. Between the results are: a) the seawater, being crystalline, warm, with little waves, makes free diving (snorkeling) and autonomous diving (scuba) possible and b) the ground that has contact with the seawater has fine-textured sand, beige color, average height of three meters where swimming activities, walks, among others, take place. The conclusions are: 1) extensive use of seawater for intensive tourist use and 2) the sandy soil supports four on-site restaurants. [ABSTRACT FROM AUTHOR]

Background and aims: Lupinus aureonitens is an endemic species of the Argentine Pampas, rare with isolated populations. Its geographic distribution is not well known, especially the location of type localities, which determines the establishment of conservation status. The objective of this work is to analyze and update the geographic distribution of the Pampas lupine by mean of historical and current sources, identify the human activities that affect it, and discuss categories of threat. M&M: Occurrence sites were compiled and analyzed from herbarium materials, historical and current bibliography, databases, and field trips. The location of the type localities was studied using old maps. Threats to the conservation of the species were listed. Results: Its presence is confirmed and updated in Buenos Aires, Córdoba, Santa Fe and La Pampa political provinces, in sandy or rocky soils of the Pampa Interior and Pampa Austral vegetation units. Conclusions: The environments in which the species is recorded are relictual landforms. The main threat to the conservation of the species is habitat fragmentation or habitat loss. With the current data it is not prudent to apply the evaluation criteria according to IUCN. The proposal to consider the species as Least Concern should be rejected, and it should be included in the Data Deficient category. For now, it is necessary to accompany future studies with in situ and ex situ conservation measures. [ABSTRACT FROM AUTHOR]

Background and aims: The functioning of arid zone ecosystems depends on the fraction of precipitation that enters the soil and can be absorbed by vegetation. Vegetation affects infiltration by modifying droplet size, altering soil structure and changing microtopography. The objective of this study was to evaluate infiltration parameters in two soil-vegetation complexes in the central Monte region of San Juan. M&M: Visual interpretation of satellite images and fieldwork identified and characterized soil-vegetation complexes (SVCs). Bare soil and covered soil were the two surface conditions defined for each SVCs. A simple ring and variable load infiltrometer performed the infiltration tests. The samples taken from the soil determined texture, organic matter content, apparent density, available nitrogen, and salinity, among others. Results and Conclusions: Two SVCs were recognized: one dominated by Prosopis flexuosa and the other by Larrea divaricata. In the first complex, the soil presented a sandy clay loam texture, while in the second the texture was sandy loam. In both SVC, mean infiltration speed (p=0.03), basic (p=0.02) and initial infiltration (p=0.02) were statistically different between bare soil and covered soil. In addition, mean infiltration rate was 2.48 times higher in the complex dominated by carob trees compared to bare soil. These results suggest that the presence of vegetation favors the infiltration and entry of water into the soil. These data could be used as inputs for the elaboration or adjustment of hydrological models of the Monte. [ABSTRACT FROM AUTHOR]

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The amount and quality of carbon from forest litter present in the soil will depend on several factors, including species composition, management practices, plantation age, climatic conditions and soil texture, among several other factors. The aims of this research were to: i) quantify the labile organic carbon content in soils with Eucalyptus grandis plantations of the Mesopotamian region in Argentina and evaluate its relationship with the amount and type of litter; and ii) identify management, edaphic and environmental factors that may influence its variation. The study was performed on young and middle age plantations having soils with sandy and clayey texture located in the Gualeguaychú district, Entre Ríos, Argentina. To quantify the labile carbon in the soil, the soluble organic carbon was extracted with a 0.5M potassium sulfate solution. Soluble organic carbon concentration did not differ according to the age of the stands, with average values of 45.6 mg kg-1 in clay soils, and of 32.8 mg kg-1 in sandy soils, showing a positive association with clay content. The highest soluble organic carbon values were recorded during the summer months, and were positively related to the increases in the water-saturated pore space and the soil biological activity. We also verified a linear and positive relationship between the amount of initial fine litter and the increase of soluble organic carbon in the soil (R² = 0.41). The reported results provide explicit ranges of variability for total organic carbon, soluble organic carbon and carbon fluxes at local level; thereby contributing to further characterize carbon modeling in forest systems. [ABSTRACT FROM AUTHOR]

Copyright of Investigación Agraria is the property of Investigacion Agraria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

One of the factors that substantially modifies the value of the apparent density is the content of water present in the soil at the time of taking the sample for its determination, due to changes in the equivalent diameter of the pores. This measurement allows knowing the ease of penetration of the roots into the soil, the total porosity of the soil, estimating the mass of the topsoil and calculating the sheets of water for irrigation. The value of apparent density is a good index of the degree of compaction or reduction of the pore space, and therefore, of the soil aeration; proving to be a good indicator of soil quality. In the present work the transformations that the apparent density of the soil undergoes in the face of changes in the water content in the soil matrix are exposed, according to the quality of the predominant clay of some Cuban soils. The functional relationships found showed that the Soils of the Groupings: Ferralitic, Vertisuelo and Brown Sialitic, according to the current Classification in Cuba, undergo notable changes in Apparent Density in the event of humidity changes, not so in soils of the Sandy Group. The objective of this work was to provide a tool to alleviate the inconveniences of the modifications suffered by the Apparent Density with humidity, according to the quality of the clay present in its mineralogy. The results showed that of the studied soils, the clayey ones, showed modifications of the values of Apparent Density due to the increase of humidity, not so the sandy ones, which can avoid errors in the calculation of the irrigation sheets to be applied. [ABSTRACT FROM AUTHOR]

The construction of earth dams has placed the stability of slopes in a plane of engineering importance of the first order, both for the economic aspect and for the undesirable consequences due to their failures. The objective of this research is to perform an analysis to define the dependence of the hydraulic conductivity curve on the degree of soil compaction. The case study is a 22 m high earth dam with a drainage prism, considering the principles of partially saturated soil mechanics for the final stages of construction and operation of the same, with three floors in the curtain of type CH and three sandy soils in the foundation. The SIGMA/W, SEEP/W and SLOPE/W tools of the GeoStudio 2012 program are used for the execution of the models. The main results obtained show that the variation in stability increases when the degree of compaction and the corresponding suction oscillate between 80 and 95% of the Standard Proctor test, for which it is concluded that it is more effective to use characteristic curves obtained for compaction degrees equal to or greater than 95%. [ABSTRACT FROM AUTHOR]

Butia lallemantii is endemic from sandy soils in the state of Rio Grande do Sul (RS). Sandblasted soils stand out for fragile characteristics of low fertility, water availability and intense sand displacement. However, studies on planting techniques, use of fertilizers and alternative products that may favor the establishment of plants in these soils are lacking. Therefore, the objective of the study was to evaluate the survival and leaf appearance of the B. lallemantii plants established by the revegetation method in sandy soil, with the increase of mineral fertilizer and hydroretentor polymer, as well as monitoring the movement of sand particles. The plants were collected in Alegrete / RS, classified in stipe diameter and kept in substrate (soil, animal waste and rice husk, 1:1:1) for eight months. In field plantation, the doses of NPK and hydrogel were randomly placed between five graded rules in the soil, for periodic sand displacement readings. Survival, appearance of live leaves and sand displacement were evaluated monthly, with a randomized block design (100 seedlings/block). Results showed higher survival and presence of living leaves in the plants of block one, and average displacement of sand in the spring period. Therefore, plants of larger stipe diameter class show higher potential for survival and larger number of live leaves, in addition, sand displacement mainly happens during spring. [ABSTRACT FROM AUTHOR]

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of DYNA - Ingeniería e Industria is the property of Publicaciones Dyna SL and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Moringa oleifera Lamark, is native to the Himalayan region, has high protein content and other nutritional characteristics particular to animal nutrition, but has limitations in terms of survival under water stress conditions both by absence or excess of water during the nursery phase, associated among others by the presence of soil phytopathogens. The objective of this study was to evaluate three types of substrates of different textural characteristics: sandy, loamy sand and a compost-sandy soil mix, as well as three frequencies of irrigation: daily and at intervals of two and three days, in the production of aerial and root biomass of moringa cv. Super Genius, with three repetitions in a randomized block design with 3x3 factorial arrangement. The experimental plot consisted of four plants. The substrate mixed compost - sandy soil in similar proportions presented higher aerial and root biomass. The frequency of daily irrigation for the mixed substrate was the appropriate strategy for the cultivation of moringa seedlings, while the increase in the interval between irrigations caused a decrease in the weight of the root system. The roots of seedlings from compost-sandy soil mix substrate presented a star-shaped radical system, while in the sandy loam and sandy soils, the roots of the seedlings had a globular shape. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes cause serious agricultural losses worldwide. Although the damage and the population densities of these parasites are higher in sandy soils, there is little information on how the texture and soil hydrodynamics affect the movement of the nematode. Whereas the movement of plant-parasitic nematodes in soil is affected by the environment, soil texture is highly relevant to the nematode mobility and efficiency in infection. Therefore, this study aimed to evaluate the influence of water flux density on plant-parasitic nematode mobility. Evaluations were performed in the Laboratory of Nematology of the Federal Rural University of Pernambuco (UFRPE) and in the Soil Physics Laboratory and Water Quality, Department of Biosystems Engineering, Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), using soil columns (11.0 cm long acrylic cylinder with 1.95 cm internal diameter and 3.0 cm2 cross section) with a peristaltic pump, under saturation and stationary flow regime. The experimental design was completely randomized in a factorial 3 (species of nematode: Meloidogyne enterolobii, M. incognita, Pratylenchus coffeae) × 2 (nematode condition: alive, dead) × 3 (soil types: Latossol, Nitosol, and washed sand) × 3 (soil density: bulk density, density 0.1 g cm3 above and below the true density of each soil) × 4 (flow rate: 5, 15, 25 and 40 ml min-1) crossed and nested arrangement with three replications. The increase in flow rate from 5 to 40 ml min-1 increased the amount of leached nematodes, although fewer M. incognita juveniles were leached than P. coffeae. Nematode mobility increased as the sand level increased or the soil density decreased. In contrast, in clay soils with density ranging from 1.1 to 1.3 (g cm-3) the dynamics of nematodes was almost nil. [ABSTRACT FROM AUTHOR]

The objective of this investigation was to define the zoning of soil liquefaction potential for the Guillermón Moncada Popular Council in the municipality of Santiago de Cuba. The engineering and geological conditions and seismic peculiarities favoring a seism to take place were assessed. The safety factor was re-calculated after determining possible maximum intensity values based on seismic magnitudes that can trigger the soil of the investigated area to liquefy. A scheme of the area's soil susceptibility to liquefaction was obtained. Based on this result, it was concluded that the sectors that are most likely to experience soil liquefaction if an earthquake of magnitudes ranging between 7,75 and 8 occurs are located towards the center-east of the Popular Council with sandy-clayey soils being predominant. This information is very useful for the location and planning of engineering construction works in the area. [ABSTRACT FROM AUTHOR]

Copyright of Revista CienciaUAT is the property of Universidad Autonoma de Tamaulipas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Soil contamination due to involuntary leakage of different products, is a permanent threat caused by economic and social development of communities. In particular, oil spills are common during the oil production process as well as during marketing, transport and storage of collection and distribution sites. There arises the initiative of evaluating changes in the mechanical properties of soils affected by spills of oil industry. For this study were selected the oil as a contaminant, and a sandy soil matrix, such as porous medium saturated with water that was pumped upflow at a rate of 12 ml min-1. We proceeded to sampling at defined time intervals, using 30 cm3 containers, samples whose fat and oil content were determined. Then soil samples were subjected to mechanical characterization and the results compared with the behavior of the soil sample unaffected by the oil spill. It is concluded that the specific gravity, the percentage of absorption and capacity of polluted sandy soil compaction, down with respect to values of undisturbed soil, while there was a slight increase in cutting resistance. [ABSTRACT FROM AUTHOR]

The influence of initial planting density (DPI) on the dynamic modulus of elasticity (MOEd) was examinated at a 28 years old Pinus radiata D. Don spacing experiment with four treatments (2500, 1667, 833 and 625 stem ⋅ ha-1 growing on sandy soil, in the Biobio Region, Chile. The MOEd acoustic technology was determined using the method of time of flying (Tv) for standing trees and the resonance method (Res) for two logs of 5 m long, extracted from the tree base to the top of each tree. MOEd was not significantly influenced by DPI in high initial stocking treatments (2500, 1667 an 833 stem ⋅ ha-1), both standing trees and logs level. In contrast, the lowest initial stocking treatment (625 stem ⋅ ha-1) had the highest MOEd significantly different in standing trees and the first the log, and similar between the first and second log. [ABSTRACT FROM AUTHOR]

In this work is described a rare species belonging to the genre Smardaea Svrček 1969, found in Oriñon (Cantabria) in sandy soil. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería de Recursos Naturales y del Ambiente is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerous studies conducted on coarse-textured soils show, significant and positive wheat yield responses when soil nitrogen (N) availability is increased, and occasional positive yield responses to sulfur (S) additions. However, the available information is not consistent for the diagnosis and analysis of the marginal contribution of S on wheat grain responses in combination with N fertilization. Thus, the objective of this study was to quantify the yield response of dryland wheat crops to N and NS fertilization and to determine the relationship between yield response and several soil properties in sandy soils. The study consisted in 34 field experiments within the semiarid and subhumid sandy pampas region (Argentina) managed under no-tillage practices. Three treatments were evaluated: i) control (without fertilization), ii) 140 kg of N ha-1 [N-NO3 soil (0-40 cm) + N fertilizer], iii) 140 kg of N ha-1 [N-NO3 soil (0- 40 cm) + N fertilizer] + 12 kg of S ha-1. A positive response to N fertilization was observed in every experimental site. Mean grain yield response to the application of N was 949 kg ha-1. Although the mean grain yield response to S fertilization was 232 kg ha-1, only 38% of the sites (13 sites) showed a significant response to this treatment. Crop response to S fertilization was not related to soil organic matter (p = 0.61), sand content (p = 0.90), soil extractable S-S042-(p = 0.29), nor soil N-N03-(p = 0.47) levels. Furthermore, it decreased with increasing maximum grain yields and it was positively related to crop responses to N fertilization. We conclude that in coarse textured soils with significant N limitations, wheat responses to S fertilization are greater and more common in low productivity sites. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Hidráulica en México is the property of Instituto Mexicano de Tecnologia del Agua (IMTA) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective was to achieve Indexes of Cut adjusted to the soils of the regions in study and to relate the same ones with simple determinations of laboratory like sedimentation volume. It was observed in the region a great disparity of methods to use for the calculation of the plane project to obtain and the application of values of relationship cut/fill without local validation. The work was carried out in Mendoza's county, 22 parcels were raised in the areas irrigated by the rivers Mendoza and Tunuyán. The averages values obtained of expansion relationship, according to the each soil, were: sandy 1.04; loam 1.4; clay 1.71; sandy loam 1.29; silt clay loam 1.71; clay loam 1.64 and silt loam 1.34. [ABSTRACT FROM AUTHOR]

This study was realized to evaluate the evaporation on different type of soil mositened with magnetized water. Five tests were realized, a sandy and clay soil were moistened with distilled water, tap water and a 0,026 M NaCl solution. Magnetic treatment of water took place by circulation into a device with 6 magnets for different times, 30, 60 and 120 minutes. The evaporation on both sandy and clay soil moistened with distiled water subjected to magnetic treatment for 60 minutes is significantly less than the control; the same effect is observed when the test is realized using tap water. [ABSTRACT FROM AUTHOR]