Download or read book The Literature of Soil Science written by Peter McDonald and published by Cornell University Press. This book was released on 1994 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of 14 discussions of the past and present literature about soil science. The topics include a historical survey, bibliometrics, introduction into developing countries, societies and their publishing influence, information systems, core monographs, primary journals, maps, and other aspec
Download or read book Sugar written by and published by . This book was released on 1928 with total page 590 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book General Technical Report RM written by and published by . This book was released on 1992 with total page 236 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The role of physical and biological soil crusts on the water balance in semiarid ecosystems written by Sonia Chamizo de la Piedra and published by Universidad Almería. This book was released on 2014-11-06 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt: In arid and semiarid areas, the interplant spaces are usually covered by physical and biological soil crusts. These crusts, though representing an almost negligible portion of the soil profile, have a number of crucial roles. Soil crusts form the boundary between soil and atmosphere and therefore control gas, water and nutrient exchange into and through soils. Concretely, in the last decade, the study of biological soil crusts (BSCs) (complex communities of cyanobacteria, algae, fungi, lichens, mosses and other microorganisms in intimate association with soil particles) has drawn the attention of a growing number of researchers due to the key role they play in numerous processes in the ecosystems where they appear. Unlike physical crusts, BSCs protect soils against erosion by water and wind, and increase soil fertility by fixing atmospheric C and N, synthesising polysaccharides and reducing nutrient losses by runoff and erosion. Through their influence on numerous properties that affect how water moves though soils such as roughness, porosity, hydrophobicity, cracking, and albedo, BSCs play a key role in water processes, such as infiltration and runoff, evaporation and soil moisture. It is widely known the role of physical crusts in decreasing soil porosity and hydraulic conductivity, thus decreasing infiltration. However, there is controversy regarding the role of BSCs in infiltration and runoff processes. Some studies indicate that BSCs increase infiltration, and consequently, decrease runoff, whereas others have reported that they decrease infiltration and increase runoff or that they have no effect on either of them. In addition, the influence of BSCs on other soil water balance components such as evaporation and soil moisture has hardly been studied and the scarce existing studies also show contradicting results. With the aim of enlightening the role that BSCs play in the water balance in semiarid areas, in this thesis it has been analysed the influence of different soil crust types, physical crusts and various developmental stages of BSCs, on key soil water balance components such as infiltration-runoff, evaporation and soil moisture, at plot scale. Furthermore, to better understand how these crusts affect hydrological processes, the influence of the type of crust and developmental stage of the crust on different properties that affect water movement and retention in soils has been analysed. Last, spectral characteristics of the different crust types, as well as of vegetation, have been examined with the aim of developing a spectral classification system for differentiation of these common ground covers in semiarid areas that allows their mapping and the modelling of the effects of the crusted areas on hydrological and erosion processes on larger spatial scales (hillslope and catchment). To conduct this research, two areas where BSCs are widespread and that represent key spatial distributions of BSCs in semiarid ecosystems were chosen in the province of Almeria (SE Spain): El Cautivo (in the Tabernas Desert), a badlands catchment with silty-loam textured soils, and Las Amoladeras (in the Cabo de Gata-Níjar Natural Park), a flat area with sandy-loam textured soils. Our results show that BSCs increase aggregate stability, water retention capacity, and organic carbon and total nitrogen content compared to physical crusts and, within BSCs, these properties increase in the crust and the underlying soil as the crust is more developed (in terms of greater biomass and later-successional species composition). The increase in soil properties with the presence of BSCs is especially noticeable in the top layer of soil (0.01 m) and decreases with depth (0.01-0.05 m) (Chapter I). Through their effect increasing surface roughness and physico-chemical soil properties, BSCs increase infiltration and decrease runoff compared to physical crusts. In general, infiltration increases with greater BSC development (Chapter II). However, there are exceptions to this general pattern that are conditioned by other factors such as the spatial scale under study or the type of rainfall. At small plot sizes (0.25 m2) and after 1h-high intensity simulated rainfall (50 mmh-1), we found that well-developed BSCs such as lichens, generate higher runoff rates than less developed BSCs as cyanobacteria, and similar runoff rates to physical crusts (Chapter II). Thus, at microplot scales and under extreme events, the effect of well-developed BSCs in enhancing infiltration due to their greater roughness can be overcome by their ability to clog soil pores when wet, thus increasing runoff. However, when the influence of BSCs on infiltration and runoff is analysed under natural rain events and at larger spatial scales (1-10 m2), we found that, in low intensity rainfalls, runoff decreases with the cover of well-developed BSCs (lichens) and this effect is higher as the plot size increases (Chapter III). Such decrease in runoff with the presence of well-developed BSCs is due to the microtopography that these crusts confer to soils. Under high intensity rainfalls, BSC cover has no significant effect on runoff yield and the main factor acting to determine runoff generation is rainfall intensity (Chapter III). The removal of the crust initially causes infiltration to increase. But this effect diminishes over time as raindrop impact reseals the surface and a new physical crust is formed that increases runoff (Chapter II). Moreover, crust disturbance by trampling but, especially by removal, causes a dramatic increase in erosion (Chapter II). Erosion also depends on the type of BSC. Well-developed crusts as lichens and mosses generate lower erosion rates than less developed crusts as cyanobacteria. Regarding the influence of BSCs on soil evaporation, under saturation conditions and warm ambient temperatures, soil water loss is quick in all types of surfaces and no significant differences are found in soils with or without BSCs (Chapter V). However, during long cold wet periods, soil water loss is faster in soils devoid of BSCs than in those covered by them. Thus, BSC-crusted soils maintain more soil moisture at the upper soil layer (0.03 m) than adjacent soils where the BSC has been removed, during wet periods. At deeper soil (0.10 m), soil moisture is similar in both BSC-crusted and uncrusted soils. The removal of the BSC causes a higher decrease in soil moisture in fine-textured soils (Cautivo), where the presence of BSCs has a stronger influence on increasing porosity and infiltration, than in coarse-textured soils (Las Amoladeras). During dry soil periods, soil moisture is similar in soils with or without BSCs (Chapter V). Last, a quantitative analysis of spectral characteristics of vegetation, physical crusts and BSC developmental stages has demonstrated the possibility of classifying these common ground covers in semiarid areas based on distinctive spectral features (Chapter VI). The application of the classification system developed to multi and hiperspectral provides the possibility for future mapping of spatial distribution and temporal dynamics of BSCs, which is crucial to incorporating the effects of crusted surfaces in current hydrological and erosion models. Summarizing, compared to physical crusts, the presence of BSCs increase physico-chemical properties of underlying soils, especially in the first centimeters of soil, and this enhancement is greater as the BSC is more developed. Due to this increase in soil properties and the higher roughness that BSCs provide to soils, BSCs increase water input by increasing infiltration and soil moisture, and soil moisture, and reduce water output by reducing soil evaporation. Hence, compared to physical crusts, the presence of BSCs and, especially the presence of well-developed BSCs, have an overall positive effect on the local water balance in semiarid ecosystems, in addition to having a major role in protecting soils from erosion.
Download or read book Geotechnical Engineering in the XXI Century Lessons learned and future challenges written by N.P. López-Acosta and published by IOS Press. This book was released on 2019-11-26 with total page 3006 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE) was held in Mexico in 1959. Every 4 years since then, PCSMGE has brought together the geotechnical engineering community from all over the world to discuss the problems, solutions and future challenges facing this engineering sector. Sixty years after the first conference, the 2019 edition returns to Mexico. This book, Geotechnical Engineering in the XXI Century: Lessons learned and future challenges, presents the proceedings of the XVI Pan-American Conference on Soil Mechanics and Geotechnical Engineering (XVI PCSMGE), held in Cancun, Mexico, from 17 – 20 November 2019. Of the 393 full papers submitted, 335 were accepted for publication after peer review. They are included here organized into 19 technical sessions, and cover a wide range of themes related to geotechnical engineering in the 21st century. Topics covered include: laboratory and in-situ testing; analytical and physical modeling in geotechnics; numerical modeling in geotechnics; unsaturated soils; soft soils; foundations and retaining structures; excavations and tunnels; offshore geotechnics; transportation in geotechnics; natural hazards; embankments and tailings dams; soils dynamics and earthquake engineering; ground improvement; sustainability and geo-environment; preservation of historic sites; forensics engineering; rock mechanics; education; and energy geotechnics. Providing a state-of-the-art overview of research into innovative and challenging applications in the field, the book will be of interest to all those working in soil mechanics and geotechnical engineering. In this proceedings, 58% of the contributions are in English, and 42% of the contributions are in Spanish or Portuguese.
Download or read book Soil Survey written by United States. Soil Conservation Service and published by . This book was released on 1942 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book section II Astronomy meteorology and seismology R S Woodward chairman written by and published by . This book was released on 1917 with total page 886 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astronomy Meteorology and Seismology written by and published by . This book was released on 1917 with total page 878 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Second Pan American Scientific Congress written by and published by . This book was released on 1917 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the Second Pan American Scientific Congress Washington U S A Monday December 27 1915 to Saturday January 8 1916 written by and published by . This book was released on 1917 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings of the second Pan American Scientific Congress Washington U S A Monday December 27 1915 to Saturday January 8 1916 1915 1916 v 2 written by and published by . This book was released on 1917 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Water Works Engineering written by and published by . This book was released on 1927 with total page 1416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Impact of Agriculture on Soil Degradation I written by Paulo Pereira and published by Springer Nature. This book was released on 2023-05-11 with total page 399 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first of two volumes that together provide a global overview of the impact of agriculture on soil degradation, tracing the most critical drivers like the use and abuse of agrochemicals, mechanization, overgrazing, irrigation, slash and burn agriculture, and the use of plastics. This book covers the main effects of agriculture practices on soil degradation in several countries from Africa, America, Asia, and Oceania, and it elucidates the impact of chemical agents on soil quality, namely, the use of fertilizers, herbicides, pesticides, soil acidification and microplastics pollution. In these continents, a large number of the population depend on agriculture, which sets an enormous pressure on the ecosystems. Divided into 13 chapters, the book offers authoritative contributions about the fundamental soil degradation problems in countries such as Argentina, Australia, Peru and Bolivia, Brazil, Chile, China, Colombia, India, Israel, Kenya, Mexico, South Africa, the United States of America. As soil degradation issues are often linked with biodiversity loss and poverty, readers will also find in this book an important discussion of the different social, economic, political, and environmental aspects contributing to soil quality and sustainable management. Given the breadth and depth of its coverage, the book offers an invaluable source of information for researchers, students, environmental managers and policymakers alike.
Download or read book Sustainable Agriculture written by Eric Lichtfouse and published by Springer Science & Business Media. This book was released on 2009-11-11 with total page 897 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainability rests on the principle that we must meet the needs of the present without compromising the ability of future generations to meet their own needs. Starving people in poor nations, obesity in rich nations, increasing food prices, on-going climate changes, increasing fuel and transportation costs, flaws of the global market, worldwide pesticide pollution, pest adaptation and resistance, loss of soil fertility and organic carbon, soil erosion, decreasing biodiversity, desertification, and so on. Despite unprecedented advances in sciences allowing to visit planets and disclose subatomic particles, serious terrestrial issues about food show clearly that conventional agriculture is not suited any longer to feed humans and to preserve ecosystems. Sustainable agriculture is an alternative for solving fundamental and applied issues related to food production in an ecological way. While conventional agriculture is driven almost solely by productivity and profit, sustainable agriculture integrates biological, chemical, physical, ecological, economic and social sciences in a comprehensive way to develop new farming practices that are safe and do not degrade our environment. In that respect, sustainable agriculture is not a classical and narrow science. Instead of solving problems using the classical painkiller approach that treats only negative impacts, sustainable agriculture treats problem sources. As most actual society issues are now intertwined, global, and fast-developing, sustainable agriculture will bring solutions to build a safer world. This book gathers review articles that analyze current agricultural issues and knowledge, then propose alternative solutions. It will therefore help all scientists, decision-makers, professors, farmers and politicians who wish to build a safe agriculture, energy and food system for future generations.
Download or read book Banana Root System towards a better understanding for its productive management written by David W. Turner and published by Bioversity International. This book was released on 2005 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Banana root deterioration and impacts on production; Root anatomy and morphology; Root physiology; Soils and root development; Pathogen: root system interactions.
