PDF superior Evolution of annual soil water surplus in Pampean Region (Argentina)

Evolution of annual soil water surplus in Pampean Region (Argentina)

Evolution of annual soil water surplus in Pampean Region (Argentina)

Floods are a constant in the central eastern region of Argentina as well as droughts. Almost every year, one of these two extreme hydrologic events takes place and sometimes, both of them. The temporal evolution of soil water surplus, during sixty years, is studied in nine meteorological stations. These are located in important areas whose land uses have economic and social impact. They are localized in the provinces of Córdoba, Santa Fe, Entre Ríos province, La Pampa and Buenos Aires. Daily meteorological data were provided by the National Meteorological Service and the period considered was 1951-2010. Soil water balance was performed according the model used Forte Lay et al. which is based on Thornthwaite-Mather method and the normal daily mean reference evapotranspiration was estimated by the Penman-Monteith formula. In the present paper the parameter soil water surplus is used as an index of flood risk. Makesens methodology was used for the statistical analysis; this is based in non parametric test Mann-Kendall for the trend study and the non parametric method Sen for the magnitude. All the analyzed stations showed different evolution of soil water surplus and have experienced flood risk in some moment of the studied period.
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21 Lee mas

Nitrogen fertilization strategies to increase yield and protein of wheat in the pampean semiarid region

Nitrogen fertilization strategies to increase yield and protein of wheat in the pampean semiarid region

The objective of this work was to evaluate the influence of nitrogen fertilization on the expression of yield and grain protein content in wheat in different environments of the semiarid Pampa region. The field experiments were carried out in Embajador Martini, Macachín and Anguil. The treatments were: control (0N), fertilization at seeding with 40 kg N.ha ­1 (40+0) and 80 kg N.ha ­1 (80+0), delayed fertilization with 40 kg N.ha ­1 (between Z3.9 and Z5.0) (0+40) and divided fertilization (40+40). The treatments were arranged in a completely randomized block design with four replicates. Five filed experiments were carried out in each site and yield, grain protein content, water use efficiency and nitrogen use efficiency were determined. The sites with IMO> 4,5% had more response to yields in comparation with control, than the sites with IMO>4,5%. The soils with >50% A+L had grater soil potential fertility, and there were significant differences between the control and 80 kg.ha ­1 at seeding o divided fertilization. Instead, the soils with <50% A+L did not show significant differences in the yields between treatments. The lowest yields in these soils were translated in higher protein grain content, reaching 11%. More soil nitrogen content increases the grain nitrogen content but decreases nutrient use efficiency. Although, rainfalls are the main restriction of this region, with a good water availability, the wheat productivity is limited by low nitrogen content.
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10 Lee mas

Contribution of macroporosity to water flux of a soil under different tillage systems

Contribution of macroporosity to water flux of a soil under different tillage systems

On the studied plots (36º 42' S and 59º 50' W), the treatments below and the same 2-yr crop sequence of maize (first year)-wheat and short-season soybean (second year) had been applied over 10 years. The climate in the region is temperate (temperatures rarely below 0 °C) and the approximate annual rainfall 1,000 mm. The experiment was arranged in a complete randomized block design with three treatments: a) conventional tillage (CT), in which the soil was moldboard-plowed to a depth of 0.19 m and disk- and tooth-harrowed to 0.10 m each year, b) chisel plow (CP) in which the soil was chiseled to a depth of 0.30 m (distance between chisel shanks: 0.35 m) and disk- and tooth-harrowed to 0.10 m each year, and (c) no tillage (NT), in which only a narrow (0.05 m) strip of the soil was drilled to sow crop seeds. There were three plots of (30 x 70 m) per treatment.
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8 Lee mas

WHO Global water, sanitation and hygiene  Annual report 2018

WHO Global water, sanitation and hygiene Annual report 2018

WHO supported development of a software tool, the WASH Accounts Production Tool (WAPT), to facilitate compilation and analyses of data and generation of WASH accounts indicators and tables by countries. The WAPT is available in English, French, Portuguese and Russian and was launched in February 2018 at a TrackFin workshop in Kenya implemented in partnership with USAID’s WASH-FIN and AMCOW. This workshop brought together government officials from nine countries that are implementing TrackFin and partners at national, regional and global levels that are supporting the process to share results and experiences. This was followed by a WAPT training workshop in May in Senegal for four francophone countries to build capacity around TrackFin methodology and the WAPT, and to generate national WASH accounts and key indicators using the WAPT. In August, WHO established an online TrackFin Community of Practice platform for posting country WASH accounts and documents and providing a discussion forum for methodological and other issues.
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52 Lee mas

Effects of soil management in vineyard on soil physical and chemical characteristics

Effects of soil management in vineyard on soil physical and chemical characteristics

Variations in soil organic matter content depend on the equilibrium between the amount of organic matter provided and its mineralization rate. In this study, organic matter contribution was the highest in CT and the lowest in HT. On the other hand, biomass management generated by each treatment also had effects over the soil organic matter content. Likewise, by incorporating the biomass generated for adventitious plants in the TT scenario, the soil organic matter is preserved at similar level to AGT treatment. The aerial biomass generated by AGT was six times greater than that generated by TT (Table 6). However, since this treatment did not involve tillage, mainly the underground part of the cover crop (approximately 25% of the aerial part) was truly incorporated into the soil (Fig. 2) while in TT all the biomass generated by the adventitious plants was incorporated into the soil. This way, the real amount of biomass incorporated into the soil was very similar in both treatments.
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8 Lee mas

Assessing soil water repellency of a sandy field with visible near infrared spectroscopy

Assessing soil water repellency of a sandy field with visible near infrared spectroscopy

The shapes of the WR regression coefficient curves are for the most part similar (Figure 5). Nevertheless, distinct differences in the regions that can be assigned mainly to OM can be observed for both coefficients. Signals related to iron oxides are present in the visible part of the spectrum (around 620 nm), with a higher intensity for the soils dried at 105°C. A broad band near 853 nm related to C–H bonds is also visible. Lower values of the regression coefficient in this region for the soils dried at 105°C indicate a lower content of molecules containing C–H bonds. The wide band in the region 1000– 1490 nm is also present in the coefficients from both models, with more pronounced intensities for the soils dried at 60°C. This region reflects the presence of multiple OM compo- nents such as macromolecules of cellulose, wax, lignin and
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11 Lee mas

Features of the annual evolution of CO2 and CH4 in the atmosphere of a Mediterranean climate site studied using a nonparametric and a harmonic function

Features of the annual evolution of CO2 and CH4 in the atmosphere of a Mediterranean climate site studied using a nonparametric and a harmonic function

Table 3 presents the main details at different places where this evolution was observed. Although measurement conditions are very varied, the yearly pattern involves one maximum and one minimum, with noticeable features being the months these values were attained and the range between them. At most of the sites, maximum values occurred in March e April. Singular cases were Hegyh ats al (Hungary) and Cabaw (The Netherlands), which dis- played maxima in December and January, respectively. Moreover, both places present the greatest ranges, above 20 ppm. Minima were mainly observed in August, with noticeable exceptions being Mauna Loa (Hawaii), whose minimum was in October, and Cape Rama (India), in November. Excluding the analysis of Tian et al. (2014), which involves different sites, the lowest range was observed at Mauna Loa, with only 6 ppm.
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9 Lee mas

Management of radioactivity in drinking-water

Management of radioactivity in drinking-water

The OIL5 and OIL6 values for drinking-water are derived on the basis of a generic dose criterion of 10 mSv in the first year after the emergency, assuming that no protective actions are taken, and that all drinking-water is contaminated at the OIL activity concentration throughout the year and using the most restrictive age group and consumption rates. The OIL values are therefore very conservative as activity concentrations in drinking-water after a nuclear or radiological emergency will reduce rapidly after the initial contamination event and will not remain at a constant level for the whole year. Ten mSv is 10% of the generic criterion of 100 mSv in the first year for implementing early protective actions and other response actions during emergency situations (IAEA, 2015). The use of 10 mSv ensures that the dose from all exposure pathways will not exceed the 100 mSv criterion. Further details on the OILs and their use are provided in Question 2.3.1 and 2.4.1. Based on the above-mentioned international standards, individual countries may develop their own national criteria, taking into account the criteria provided in these international standards as well as local prevailing circumstances (e.g. environmental, demographic, social, political, economic and other factors). The aim of giving consideration to all these
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124 Lee mas

Quality assessment of irrigation water related to soil salinization in Tierra Nueva, San Luis Potosí, Mexico

Quality assessment of irrigation water related to soil salinization in Tierra Nueva, San Luis Potosí, Mexico

Thirteen municipalities located in the southeastern part of the San Luis Potosí state are catalogued as high vulnerable to climate change. According to the report of Centro de Ciencias de la Atmósfera de la UNAM (Fernández-Eguiarte et al., 2015), Tierra Nueva has medium climatic exposition, low climatic sensitivity to climate change, high adaptive capacity to climate change, and low vulnerability to climate change. These is good for the region in terms of exposition to this phenomena, however, long-term monitoring should be addressed in this zone. The authors consider that the results presented in this paper can be taken into account to include the Santa María del Río aquifer in the Comisión Nacional del Agua national inventory of aquifers with marine intrusions or under phenomena of soil salinization and saline groundwater (CONAGUA, 2013).
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15 Lee mas

Evolution of the big deals use in the public universities of the Castile and Leon region, Spain

Evolution of the big deals use in the public universities of the Castile and Leon region, Spain

However, download statistics as a measure of journal use should be analyzed with some caution (Boots et al., 2007). These measurements only tell us if an article has been downloaded, but do not tell us if it was read, if it was of interest, or if it was useful for teaching or research. Nevertheless, its usefulness as a starting point for the evaluation of collections is widely recognized and is considered the most reliable information on the use of electronic journals (Blecic et al., 2013). In the abundant bibliography published on the evolution of article downloads, a continued growth in the use of elec- tronic journals has been observed (Boukacem-Zeghmouri; Schöpfel, 2008; Boukacem-Zeghmouri et al., 2016; Gorraiz; Gumpenberger; Schlögl, 2014; Rodríguez-Bravo; Alvite-Díez, 2011; Rodríguez-Bravo; Alvite-Díez; Barrionuevo-Almu- zara, 2012; Rodríguez-Bravo et al., 2008; 2012; Tripathi; Kumar, 2014; Tetteh, 2018). This has been driven by the adop- tion of the big deal license model, which allows researchers to have access to huge amounts of scientific articles that would be difficult to obtain otherwise. An increase in downloads should be valued positively, since there are studies that have shown a correlation between the number of downloads and the productivity of researchers (Jung et al., 2015; Rafi; JianMing; Ahmad, 2019).
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17 Lee mas

Evolution of neurocontrollers in changing environments

Evolution of neurocontrollers in changing environments

EA have been used to evolve a population of controllers. At the end of the evolutionary process, the best controller is selected, ”frozen” and put to work. Again the controller is fixed, and cannot cope with changing environments. The usual approach to solve the problem is to restart the evolutionary process, in order to get an adapted controller. Restarting from a random population is an approach that can be useful in the third adapting situation (see section 1), but it is a wastefull for drifting systems. In order to allow the EA to restart from a better position, a memory must be added. Usually, the memory does not store a complete population, but just numerical information on the best and/or the worst decisions that have been done in the past. In some cases is the operator rates, the number of violated constraints in the individuals, individuals that represents populations (virtual liders [15]), etc. Experiments were also carried by storing complete populations in order to study the readaptation capabilities faced to important environmental changes. The conclusion is that the evolutionary process must be started from early populations, since in other case, the convergence produced on them makes impossible for the EA to get good solutions [13].
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12 Lee mas

Chaetophractus vellerosus (Mammalia: Dasypodidae) in the Ensenadan (Early - Middle Pleistocene) of the southeastern Pampean region (Argentina) . Paleozoogeographical and paleoclimatic aspects

Chaetophractus vellerosus (Mammalia: Dasypodidae) in the Ensenadan (Early - Middle Pleistocene) of the southeastern Pampean region (Argentina) . Paleozoogeographical and paleoclimatic aspects

disjunct distribution (a continuous main area comprising the Gran Chaco and central Argentina, and a secondary area in the coastal region of Buenos Aires Province) attributed to a wider [r]

15 Lee mas

Assessment of Soil Quality in AndosolsUsing Silvopastoral Systems

Assessment of Soil Quality in AndosolsUsing Silvopastoral Systems

One of the most interesting findings was the bioavailability of P, whose values significantly increased (p <0.05) from medium to high in no less than one year of running the measurements in the soil (Table 2). These results could be explained by the ability of A. acuminata to colonize the roots with ecto-mycorrhizal and arbuscular mycorrhizal fungi which had an impact on some soil parameters such as pH, water holding capacity, available phosphorus, organic matter and total nitrogen [27]. Besides, a great variation of richness and composition in ecto-mycorrhizal associated with A. acuminata, depended on their geographical location [28]. On the other hand, the study on nutrient and mass litter in the top soil of ten tropical tree species suggested that the soil P associated with trees was on average twice that of the grasses [29]. These results were consistent with high levels of litter production in the SPS in which the P return through the litter was 1–3 kg ha −1 yr −1 , while in grasses, it was only 0.2–0.8 kg ha −1 yr −1 [20]. An implication of this study is the
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8 Lee mas

A new large didelphid of the genus Thylophorops (Mammalia: Didelphimorphia: Didelphidae), from the late Tertiary of the Pampean Region (Argentina)

A new large didelphid of the genus Thylophorops (Mammalia: Didelphimorphia: Didelphidae), from the late Tertiary of the Pampean Region (Argentina)

For comparative purposes we extended our calculations to the remaining species of Thylophorops: T. chapalmalensis (Fig. 5) and T. perplanus (Fig. 6), as well as to two species of Hyperdidelphys, another large, extinct didelphid. The molar locus used is the m3 with the exception of T. perplanus, in which the analyzed molar values are those of the m2. Table 1 summarizes the equations, associated coefficients, and estimated body masses for selected large didelphids. Estimations were obtained both from molar length and molar area. Because of the lack of published data on measurements of individual molars for D. virginiana, the largest liv- ing opossum, this species was not added to the pooled sample. Weight measurements for this species in Table 1 were taken from Gardner (1982).
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12 Lee mas

Implementation of the Heated Pulsed Theory using actively heated fiber optics: measurements of soil volumetric water content and soil volumetric heat capacity

Implementation of the Heated Pulsed Theory using actively heated fiber optics: measurements of soil volumetric water content and soil volumetric heat capacity

Connectors are critical elements in DTS systems due to the fact that they are the first element to transmit and receive the light pulse and the backscattered light. Connectors must be checked periodically in order to ensure perfect working conditions. They must be free of any contamination and held in good physical contact in order to assure that intensity is purely a function of the cable optics rather than the connector conditions. According to Berdinskikh et al. (2003), a 1-micrometer dust particle on a single-mode fiber core can lead to 0.05 dB loss in the light signal. Unfortunately, even under ideal conditions with a clean connector, under changing thermal conditions the plastics employed in these connectors can subtly deform, leading to slight changes in optical transmission efficiency. For this reason, if connectors are employed, it is essential to also install reference baths beyond the connector (i.e., on the cable for which precise temperature measurements are required) to correct for any errors due to changing optical efficiency of the connector. Fusion splices are a preferred approach to joining fiber optics, and are frequent required in DTS installations to solve critical fiber damages, fiber breaks or when the circumstances require it (see APPENDIX.I). Splices are delicate operations which require a splice suited to the specific fiber employed, and skillful operators to prepare the fiber and carry out the protection of the splice once completed. Basically, it takes 3 steps: (1) preparation of the cable (stripping, cleaning and cleaving), (2) alignment and fusion and, finally, (3) protection.
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117 Lee mas

Macroecology and evolution of migration in fishes

Macroecology and evolution of migration in fishes

Historical constraints and environmental conditions affect the emergence and evolution of life history traits that allow species to persist in ecological systems. One of these attributes, migratory strategies, has been the focus of several studies but as yet we lack a consensus on what constitute the main drivers of changes in these strategies. Fishes are particularly suitable for these kinds of studies, given their diversity of migratory strategies (e.g. diadromy, oceanodromy, potamodromy). For these groups, different hypotheses have been proposed in order to explain the spatial variation in the incidence of strategies: productivity, kinetic energy, environmental heterogeneity, and genetic predisposition. The objective of this work is to analyze fish migrations from a macroecological perspective to estimate the extent to which different environmental variables and historic biogeographic factors influence fish migratory life histories. Using data from public domain museum records, global repositories, and global measures of temperature, productivity, precipitation and heterogeneity, we spatially analyzed the distribution of migratory fish using 1799 species and compared it to 1602 non-migratory fishes. After analyzing the individual roles of productivity and temperature in shaping biodiversity, we conducted path analyses, including phylogenetic structure (PCPS). Results show that the different migratory strategies are not evenly distributed around the globe and that phylogeny is a relevant variable in shaping the current patterns. Productivity is positively related to species richness, except for anadromy and potamodromy, where we observed a unimodal curve, suggesting a dominant influence of competitive exclusion. Temperature significantly drives migratory species richness (except for anadromy), but in an indirect way. Overall, migratory fish richness can be explained by the interaction of multiple variables, such as productivity, temperature, environmental heterogeneity, and the role of phylogeny, but these variables interact differentially in each strategy. The role of environmental heterogeneity, measured as temperature seasonality and annual range is strongest for anadromous species, which helps explain their skewed distribution towards higher latitudes and why the kinetic-energy hypothesis fails in explaining their richness patterns.
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184 Lee mas

Environmental services of water resources, as part of the Ocaña region city proposal

Environmental services of water resources, as part of the Ocaña region city proposal

The article establishes a conceptual framework of the Ocaña region city, taking as axis the environmental services of the water resource; in this sense, a reflection is made around the city region and environmental services, and subsequently a cartographic delimitation is made of what could be a proposal of the Ocaña Region city based on water resources through the basins where it is supplied. As a main result, a delimitation was designed on how Ocaña should be understood from the water supply and responsibilities regarding its use with the other municipalities, due to this, the Algodonal River is taken as the main water source of the city and as references, the municipalities with which the city is related, with a view to contributing to a proposal of the Ocaña region city. It was possible to identify the relations of the city of Ocaña with the water environmental services of the region, highlighting on the one hand its relationship with other municipalities, strategic ecosystems and water basins. Cartographically delimited a proposal of city region starting from the ordering of the basin of the cotton river, dividing it into high, medium and low basin. It is concluded that the city of Ocaña has been built from its environmental relations with the region and that this leads to the need to plan a new city model, based on the recognition and responsibility of this within a proposal of the city region.
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7 Lee mas

Experimental study of a photovoltaic direct current water pumping system for irrigation in rural isolated Region of Arequipa, Peru

Experimental study of a photovoltaic direct current water pumping system for irrigation in rural isolated Region of Arequipa, Peru

agriculture, one of the main activities of isolated rural zones. This situation creates a necessity for the optimization of irrigation sys- tems, which would increase the yield in the process of planting and harvesting, and the income of the population [3]. Moreover, the lack of governmental support for the development of solutions generates uncertainty and causes migration from the countryside to the city. To face these social, economic, and environmental issues, photovoltaic systems adapted to the climatic characteristics of the region are an economic, reliable, and eco-friendly alterna- tive [4,5]. For example, these systems can contribute to the expan- sion of the electrical power grid in the distant regions [6], which would allow the development of different economic activities, such as agricultural irrigation or cattle raising [7], at lower costs [8].The use of photovoltaic energy brings with it economic, social, and environmental benefits, providing the population with access to telecommunication systems in rural zones [9], and thus improv- ing the business opportunities and prospects that can contribute to the development of the region. On the other hand, the principal disadvantage of the use of photovoltaic energies is the initial investment cost, which is, however, recoverable over time [10]. Moreover, the price of photovoltaic panels decreases continu- ously, making its use in different applications feasible. Today, monocrystalline silicon cell panels, for power generation and brushless motors, for water pumping, represent the most efficient and cost effective technology [11–17]. Some research projects have been undertaken specifically in isolated communities. In 2010, Gonzales conducted a project—Photovoltaic, Pumping- System Prototype for Cooperation Projects towards Development with Appropriate Technologies [18]—in which the author pro- vided information regarding the installation of a particular water- pumping prototype whose energy is derived from photovoltaic panels, which feed the motor. He performed multiple simulation runs, changing parameters such as the need for maintenance of the system, so that its functioning could be optimized. The author concluded that the technology could be implemented in develop- ing countries with a low quality of life, which was also affirmed by Sagahon [19]. In 2013, Perez presented a project—Water- Pumping Systems Utilizing Photovoltaic, Solar Energy [20]—for which the author performed an economic study regarding the utili- zation of photovoltaic energy for the pumping of water and addressing subjects as the necessary investment and the subse- quent returns on investment of this kind of projects. The author proposed that legislation was updated so that private individuals could opt for this type of technology for the generation of electri- cal power. Cuadros et al. [21] presented a procedure for the sim- plified dimensioning and measurement of photovoltaic pumping systems, which he calls photo-irrigation.
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11 Lee mas

Remediation of Water Contamination in Colombia: Nanotechnology for Water Treatment

Remediation of Water Contamination in Colombia: Nanotechnology for Water Treatment

technology that uses composite nanotparticles which emit silver ions that destroy bacteria and other contaminants from water. Researchers at the Indian Institute of Technology Madras in Chennai, India, have developed this purification device that filters microbes, bacteria and viruses, and chemicals such as arsenic, lead and pesticides from water (Chow, 2013 ) (see figure 19). According to the developers, the filtration process takes approximately an hour, and current prototype containers hold up to ten litres of water. They are currently trialling the devices in rural communities of India and claim this would shortly be commercially scalable and could cost as little as $2.50 per year to deliver safe water for a family.
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68 Lee mas

Intra-annual patterns of tracheid size in the Mediterranean tree Juniperus thurifera as an indicator of seasonal water stress

Intra-annual patterns of tracheid size in the Mediterranean tree Juniperus thurifera as an indicator of seasonal water stress

thurifera trees growing under differing water conditions with the aim (¿) to recognize intra- annual wood cell dimension patterns, (ii) to assess whether ring width and cell anatomical[r]

15 Lee mas

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