Article

Soil Maps of the United States of America

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Abstract

National soil maps provide an important archive depicting soil science theory and ideas behind the application of soils information at the time the maps were created. A look at soil maps of the United States produced since the beginning of the twentieth century shows a move from a geologic-based concept of soils to a pedologic concept of soils. These maps also show changes from property-based systems to process-based, and then back to property-based, and ideas on diagnostic mapping of soil properties changed over time. The national soil mapping program in the USA was established in 1899. The earliest nation-wide soil map was published by M. Whitney in 1909 consisting of soil provinces that were largely based on geology. In 1912 G.N. Coffey published the first country-wide map based on soil properties; the map showed 22 soil units belonging to 5 divisions based on parent material, color and drainage. The next national map was produced by C.F. Marbut, H.H. Bennett, J.E. Lapham, and M.H. Lapham in 1913 and showed 13 broad physiographic units that were further subdivided into soil series, soil classes and soil types. In 1935 Marbut drafted a series of maps based on soil properties, but these maps were replaced as official U.S. soil maps in 1938 with the work of M. Baldwin, C.E. Kellogg, and J. Thorp. Modern soil maps appeared in the 1960s with the 7th Approximation and followed with the 1975 and 1999 editions of Agriculture Handbook number 436, Soil Taxonomy.

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... Geologists were typically hired to conduct the soil mapping because academic programs to train soil mappers did not exist, but geologists were trained in field mapping skills (Coffey, 1911;Lapham, 1949). Not surprisingly, these early USA maps were strongly influenced by geology (Brevik and Hartemink, 2013). National soil survey programs also began in several other countries during the 20th Century, including Russia in 1908, Canada in 1914, Australia and Great Britain in the 1920s, and China in 1931(Simonson, 1989, Mexico in 1926 (Gonzalez et al., 2010), Sri Lanka in 1930 (Mapa, 2006), Poland in 1935 (Bialousz et al., 2005), The Netherlands in 1945 (Hartemink and Sonneveld, 2013), Ghana in 1946 (Effland et al., 2006), Malaysia in 1955 (Paramananthan et al., 2006) and Spain in the first decades of the 20th Century (Bellinfante et al., 2013;Guerra Delgado et al., 1968). ...
... Beyond improvements to the fundamentals of soil mapping, new geospatial technologies provide opportunities to analyze and communicate information about the soil landscape in new ways (Goodchild, 1988(Goodchild, , 1992. Soil mapping has always had a close relationship with the development of soil knowledge (Simonson, 1991;Brevik and Hartemink, 2013;Miller and Schaetzl, this issue). Efforts to map soil provide data and raise new questions about the spatial distribution and environmental context of soils, which informs research on soil formation processes (Jenny, 1941;Hole and Campbell, 1985;Schad et al., 2001). ...
... For these reasons, soil classification systems underwent considerable change through the 20th century. The National Cooperative Soil Survey (NCSS) in the USA has used at least four formally adopted soil classification systems since nationallycoordinated soil survey efforts began in 1899 (Table 2), and others that were not formally adopted have been proposed (Brevik and Hartemink, 2013). Other countries have evolved through multiple philosophies of soil classification over the last several decades as well, including Australia, Austria, Brazil, Canada, China, Cuba, France, Germany, Hungary, Japan, New Zealand, Romania, Russia/USSR, and Switzerland (Krasilnikov et al., 2009). ...
Article
Soil mapping, classification, and pedologic modeling have been important drivers in the advancement of our understanding of soil from the earliest days of the scientific study of soils. Soil maps were desirable for purposes of land valuation for taxation, agronomic planning, and even in military operations. Soil mapping required classification systems that would allow communication of mapped information, classification systems required understanding of the soil system, and gaining that understanding included the creation of soil models. Therefore, advancement in one of these highly interrelated areas tended to lead to corresponding advances in the others, and these relationships persist into the modern era. Although many advances in our understanding of the soil system have been made since the late 1800s, when soil science blossomed into a scientific discipline in its own right, there are still many unanswered questions and additional needs in soil mapping, classification, and pedo-logic modeling. New technologies including GPS, GIS, remote sensing, on-site geophysical instrumentation (EMI, GPR, PXRF, etc.), and the development of statistical and geostatistical techniques have greatly increased our ability to collect, analyze, and predict spatial information related to soils, but linking all of this new information to soil properties and processes can still be a challenge and enhanced pedologic models are needed. The expansion of the use of soil knowledge to address issues beyond agronomic production, such as land use planning, environmental concerns, food security, energy security, water security, and human health, to name a few, requires new ways to communicate what we know about the soils we map as well as bringing forth research questions that were not widely considered in earlier soils studies. At present this information is communicated using dozens of national soil classification systems as well as WRB, but a more universal soil classification system would facilitate international communication of soils information. There are still many significant needs in the area of soil mapping, classification, and pedologic modeling going into the future.
... Geologists were typically hired to conduct the soil mapping because academic programs to train soil mappers did not exist, but geologists were trained in field mapping skills (Coffey, 1911;Lapham, 1949). Not surprisingly, these early USA maps were strongly influenced by geology (Brevik and Hartemink, 2013). National soil survey programs also began in several other countries during the 20th Century, including Russia in 1908, Canada in 1914, Australia and Great Britain in the 1920s, and China in 1931(Simonson, 1989, Mexico in 1926 (Gonzalez et al., 2010), Sri Lanka in 1930 (Mapa, 2006), Poland in 1935 (Bialousz et al., 2005), The Netherlands in 1945 (Hartemink and Sonneveld, 2013), Ghana in 1946 (Effland et al., 2006), Malaysia in 1955 (Paramananthan et al., 2006) and Spain in the first decades of the 20th Century (Bellinfante et al., 2013;Guerra Delgado et al., 1968). ...
... Beyond improvements to the fundamentals of soil mapping, new geospatial technologies provide opportunities to analyze and communicate information about the soil landscape in new ways (Goodchild, 1988(Goodchild, , 1992. Soil mapping has always had a close relationship with the development of soil knowledge (Simonson, 1991;Brevik and Hartemink, 2013;Miller and Schaetzl, 2015-this issue). Efforts to map soil provide data and raise new questions about the spatial distribution and environmental context of soils, which informs research on soil formation processes (Jenny, 1941;Hole and Campbell, 1985;Schad et al., 2001). ...
... For these reasons, soil classification systems underwent considerable change through the 20th century. The National Cooperative Soil Survey (NCSS) in the USA has used at least four formally adopted soil classification systems since nationallycoordinated soil survey efforts began in 1899 (Table 2), and others that were not formally adopted have been proposed (Brevik and Hartemink, 2013). Other countries have evolved through multiple philosophies of soil classification over the last several decades as well, including Australia, Austria, Brazil, Canada, China, Cuba, France, Germany, Hungary, Japan, New Zealand, Romania, Russia/USSR, and Switzerland (Krasilnikov et al., 2009). ...
Article
Conventional soil mapping is costly and time consuming. Therefore, the development of quick, cheap, but accurate methods is required. Several studies highlight the importance of developing regional soil spectral libraries for digital soil mapping, but few studies report on the use of these libraries to aid digital mapping of soil types. This study aims to produce a digital soil map using as training set Visible and Near Infra-Red (Vis-NIR) spectra from local soil samples, a regional spectral library and terrain attributes. The soils were sampled in 162 locations on a 270-ha farm in the municipality of Piracicaba, São Paulo, Brazil. Spectra from topsoil and subsoil were measured in laboratory (400-2500 nm) and arranged as multi-depth spectra. Information was summarized by principal component analysis. Regression tree models were calibrated to predict principal components (PC) scores based on terrain attributes. After calibration, the models were applied to the entire study site, resulting in PC score maps. Fuzzy c-means and PC maps were used to define the soil mapping units (MU). Based on fuzzy centroids, representative samples (RS) were defined to the MU. Munsell soil color and soil order were predicted from soil spectra and used to characterize the MU. The regression tree model had a good fit for PC1, with an r2 of 0.92, and a satisfactory r2 for PC3, PC4, and PC5, respectively 0.58, 0.66 and 0.53. The fuzzy clustering defined seven MU. The R2 for Munsell color predictions were 0.94 (hue), 0.96 (value) and 0.73 (chroma). Soil order had good agreement in validation, with kappa coefficient of 0.41. The methodology indicates the potential of Vis-NIR spectra to improve soil mapping campaigns and consequently provides a product similar to a conventional soil map.
... Therefore, Whitney's influence slowed the adoption of soil ideas based on the new Russian concepts within the USA. The idea favored by Whitney of soils as a fairly simple product of rock weathering, and thus being largely geological in nature, persisted in the USA for many years into the 20th Century (Brevik and Hartemink, 2013). ...
... Whitney's (1909) soil classification system (table fromBrevik and Hartemink, 2013).Examples are given here to demonstrate how the system worked. Soil series with a small number of soil types have been chosen to keep the table small. ...
Article
Interest in understanding America’s soils goes back to prehistory with the Native Americans. Following European settlement, notable individuals such as Thomas Jefferson and Lewis and Clark made observations of the soil resource. Moving into the 1800s, state geological surveys became involved in soil work and E.W. Hilgard started to formulate ideas similar to those that would eventually lead to V.V. Dokuchaev being recognized as the father of modern soil science. However, Hilgard’s advanced ideas on soil genesis were not accepted by the wider American soil science community at the time. Moving into the 1900s, the National Cooperative Soil Survey, the first nationally organized detailed soil survey in the world, was founded under the direction of M. Whitney. Initial soil classification ideas were heavily based in geology, but over time Russian ideas of soil genesis and classification moved into the American soil science community, mainly due to the influence of C.F. Marbut. Early American efforts at the scientific study of soil erosion and soil fertility were also begun in the 1910s and university programs to educate soil scientists started. Soil erosion studies took on high priority in the 1930s as the USA was impacted by the Dust Bowl. Soil Taxonomy, one of the most widely utilized soil classification systems in the world, was developed from the 1950s through the 1970s under the guidance of G.D. Smith and with the administrative support of C.E. Kellogg. American soil scientists, such as H. Jenny, R.W. Simonson, D.L. Johnson, and D. Watson-Stegner, developed influential models of soil genesis during the 20th Century, and the use of soil information moved beyond agriculture to include issues such as land-use planning, soil geomorphology, and the interactions between soils and human health.
... Soil maps were desirable for purposes of land valuation for taxation, agronomic planning (Brevik and Hartemink, 2010;Miller and Schaetzl, 2014), and in military operations (Lark, 2008;Brevik et al., 2015a). Soil mapping required classification systems that would allow accurate and succinct communication of mapped information (Brevik and Hartemink, 2013), classification systems required understanding of the soil system (Marbut, 1922), and gaining that understanding included the creation of soil models (Wilding, 1994). Therefore, advancement in one of these highly interrelated areas tended to lead to corresponding advances in the others, and these relationships persist into the modern era. ...
... The earliest models of soil formation were probably those that viewed soils as a function of the geologic material they formed in (Brevik and Hartemink, 2013), but a major milestone in the development of soil science as an independent, scientific field of study was the development of Dokuchaev's functional-factoral model, which became a major driving force in the mapping and classification of soils internationally within 50 years of its introduction (Brevik et al., 2015b). Other major milestones in the development of pedogenic models include Jenny's (1941) casting of the five soil forming factors into state factors in a theoretically solvable equation, Simonson's (1959) process-systems model, Runge's (1973) energy transfer model, andJohnson andWatson-Stegner's (1987) evolutionary model. ...
... While the concept of the soil series has changed over the years, the term soil series has been the longestlived term in U.S. soil classification. It has appeared in every official classification system used by the U.S. soil survey (Brevik and Hartemink, 2013). The first classification system was put together by Milton Whitney in 1909 and had soil series at its second lowest level, with soil type at the lowest level. ...
... When Soil Taxonomy was released in 1975, soil series became the most detailed (lowest) level of the classification system, and the only term maintained throughout all U.S. classifications to date. While the number of recognized soil series have increased steadily throughout the history of U.S. soil survey, there was a rapid increase in the recognition of new soil series following the introduction of Soil Taxonomy (Brevik and Hartemink, 2013). ...
Conference Paper
Full-text available
Organized national soil survey began in the United States in 1899, with soil types as the units being mapped. The soil series concept was introduced into the U.S. soil survey in 1903 as a way to relate soils being mapped in one area to the soils of other areas. The original concept of a soil series was all soil types formed in the same parent materials that were of the same geologic age. However, within about 15 years soil series became the primary units being mapped in U.S. soil survey. Soil types became subdivisions of soil series, with the subdivisions based on changes in texture. As the soil series became the primary mapping unit the concept of what a soil series was also changed. Instead of being based on parent materials and geologic age, the soil series of the 1920s was based on the morphology and composition of the soil profile. Another major change in the concept of soil series occurred when U.S. Soil Taxonomy was released in 1975. Under Soil Taxonomy, the soil series subdivisions were based on the uses the soils might be put to, particularly their agricultural uses (Simonson, 1997). While the concept of the soil series has changed over the years, the term soil series has been the longest-lived term in U.S. soil classification. It has appeared in every official classification system used by the U.S. soil survey (Brevik and Hartemink, 2013). The first classification system was put together by Milton Whitney in 1909 and had soil series at its second lowest level, with soil type at the lowest level. The second classification system used by the U.S. soil survey was developed by C. in 1913. It had soil series at the second highest level, with soil classes and soil types at more detailed levels. This was followed by another system in 1938 developed by M. Baldwin, C.E. Kellogg, and J. Thorp. In this system soil series were again at the second lowest level with soil types at the lowest level. The soil type concept was dropped and replaced by the soil phase in the 1950s in a modification of the 1938 Baldwin et al. classification (Simonson, 1997). When Soil Taxonomy was released in 1975, soil series became the most detailed (lowest) level of the classification system, and the only term maintained throughout all U.S. classifications to date. While the number of recognized soil series have increased steadily throughout the history of U.S. soil survey, there was a rapid increase in the recognition of new soil series following the introduction of Soil Taxonomy (Brevik and Hartemink, 2013).
... Solving the problems of modern soil mapping remains an important and urgent task (Adhikari et al., 2014;Brevik et al., 2016;Nachtergaele et al., 2000). Without this it is impossible to achieve progress in theoretical and applied soil science (Brevik and Hartemink, 2013;Jafari et al., 2013;Ma et al., 2019;Miller and Schaetzl, 2015;Rozanov, 1977;Rozova, 1986;Savin et al., 2019;Simonson, 1991). At the same time, it is widely believed that the current situation in soil mapping could be improved by means of new technologies, tools and methods. ...
... Currently, the scientific purposes of soil mapping play a secondary role compared to practical (applied) ones. Research is not aimed at creating maps, which can become an important driving force in our understanding of soils (Brevik et al., 2016;Brevik and Hartemink, 2013;Hartemink et al., 2013;Miller and Schaetzl, 2015;Simonson, 1991), but at creating maps for practical purposes and, above all, to ensure sustainable use, inventory and accounting of soils and other natural resources (Arrouays et al., 2017;Baruck et al., 2016;Pereira et al., 2017). However, Rozanov (1977) notes that soil geography has two main scientific tasks: firstly, displaying the soil cover on the map, and secondly, its explanation, that is, a theoretical justification for the origin and current state of the soil cover. ...
Article
The article analyzes the problems of modern soil mapping and offers a new, interdisciplinary approach to overcoming them. Among these problems, the most noticeable are the following: harmonization and thematic content of soil maps, multiscale soil mapping, and global soil map. It is shown that the main reasons of problems in modern soil mapping are the recognition of the priority of the practical purposes of soil mapping over the scientific ones, the lack of understanding of the relationship between soil mapping and the conceptual soil classification, the neglect or misuse of the systems approach and contemporary theories of classification, the lack of a universal soil classification system, and an orientation toward new technological advances. It is emphasized that hopes for a successful solution to the problems of soil mapping using the latest technologies, tools and methods are largely unjustified, since, first of all, a consistent theory of soil mapping is necessary.The theoretical foundations and technology for multiscale soil-landscape mapping in a GIS environment are described. Multiscale soil-landscape maps are defined as a system of interconnected maps of all scale ranges, which have a single classification basis and coordinated thematic content. They contain integrated information about soils and landscape systems, which are landscapes, considered from the point of view of the systems approach, and display soils mainly as derived landscape system elements. Another distinctive feature of multiscale soil-landscape maps is that they reflect the relationship between soil properties, on the one hand, and properties of the basic landscape system elements (parent rocks, air, water, and organisms), on the other. The advantages of multiscale soil-landscape mapping in comparison with traditional and digital are shown. From a practical point of view, multiscale soil-landscape maps are considered as the basis for making scientifically sound decisions on sustainable nature management at all levels - from global to local.
... The Russian V.V. Dokuchaev and American C.F. Marbut made great contributions to our understanding of how soils were formed (Simonson, 1989). That understanding formed an important base for the development of soil mapping in Russia and the USA (Brevik and Hartemink, 2013;Hartemink et al., 2013). As will be discussed in the next section, the agricultural chemists and agricultural geologists worked with different definitions of the soil. ...
... The classification scheme of Morton (1843) had several classes, some based on soil texture, others on the diluvium and alluvium, and parent rock. Also the early soil maps had sand and clay as a diagnostic criteria for distinguishing mapping units, for example, the first state soil maps in USA (Brevik and Hartemink, 2013). The soil mapping and classification systems in the 1800s largely followed how the soils were defined and perceived. ...
Article
The soil is defined differently by soil scientists, and its definition has changed over time. This paper reviews how the definition of the soil has changed since the early 1800s by selecting and listing 81 definitions given in a wide range of soil science books, handbooks, glossaries and dictionaries. Initial definitions of the soil were based on developments in agricultural chemistry or geology. The soil was seen as a production factor (medium) for agriculture that needed to be understood before it could be improved, or the soil was defined as disintegrated rocks mixed with organic matter. Definitions were rudimentary reflecting the overall level of understanding. Soil variation was not well understood. Overarching soil definitions appeared in the late 1800s following some major shifts in the understanding and knowledge about soils. The definition of the soil was particularly relevant for soil survey and in soil classification, because it affected how soils were viewed in the field and represented in a two dimensional way (soil maps). Both the World Reference Base (WRB) and Soil Taxonomy have defined the soil, but standard field books describing soils often lack a definition. Most of the definitions in dictionaries and glossaries are detailed stressing the organic and inorganic part of the soil as well the origin, complexity, and some of its functions. Current soil definitions have a more environmental outlook reflecting the broadening of the soil science discipline but definitions will change following scientific advances and discovery. Soils are defined differently by subdisciplines. Considerable research is conducted nowadays outside soil science departments and research centres, and for some researchers the soil may solely be a medium – just as it was in the mid-1800s. The effect of increased specialisation and expansion in soil science causes the detail of the investigation to prevail over the idea of soil as a complex dynamic system that is part of a much wider Earth system. This review ends with a proposal for a scientific definition of soil, and a definition for lay persons and the general public.
... The Russian V.V. Dokuchaev and American C.F. Marbut made great contributions to our understanding of how soils were formed (Simonson, 1989). That understanding formed an important base for the development of soil mapping in Russia and the USA (Brevik and Hartemink, 2013;Hartemink et al., 2013). As will be discussed in the next section, the agricultural chemists and agricultural geologists worked with different definitions of the soil. ...
... The classification scheme of Morton (1843) had several classes, some based on soil texture, others on the diluvium and alluvium, and parent rock. Also the early soil maps had sand and clay as a diagnostic criteria for distinguishing mapping units, for example, the first state soil maps in USA (Brevik and Hartemink, 2013). The soil mapping and classification systems in the 1800s largely followed how the soils were defined and perceived. ...
Data
The soil is defined differently by soil scientists, and its definition has changed over time. This paper reviews how the definition of the soil has changed since the early 1800s by selecting and listing 81 definitions given in a wide range of soil science books, handbooks, glossaries, and dictionaries. Initial definitions of the soil were based on developments in agricultural chemistry or geology. The soil was seen as a production factor (medium) for agriculture that needed to be understood before it could be improved, or the soil was defined as disintegrated rocks mixed with organic matter. Definitions were rudimentary reflecting the overall level of understanding. Soil variation was not well understood. Overarching soil definitions appeared in the late 1800s following some major shifts in the understanding and knowledge about soils. The definition of the soil was particularly relevant for soil survey and in soil classification because it affected how soils were viewed in the field and represented in a two dimensional way (soil maps). Both the World Reference Base (WRB) and Soil Taxonomy have defined the soil, but standard field books describing soils often lack a definition. Most of the definitions in dictionaries and glossaries are detailed stressing the organic and inorganic part of the soil as well the origin, complexity, and some of its functions. Current soil definitions have a more environmental outlook reflecting the broadening of the soil science discipline but definitions will change following scientific advances and discovery. Soils are defined differently by subdisciplines. considerable research is conducted nowadays outside soil science departments and research centres, and for some researchers the soil may solely be a medium—just as it was in the mid-1800s. The effect of increased specialisation and expansion in soil science causes the detail of the investigation to prevail over the idea of soil as a complex dynamic system that is part of a much wider Earth system. This review ends with a proposal for a scientific definition of soil, and a definition for lay persons and the general public.
... Maps have been fundamental in the advancement for our scientific knowledge about soils and to communicate information in an understandable manner (Brevik and Hartemink, 2013). Despite the great advances observed since the end of the 19th century, the emergence of new technologies (e.g., geographic information systems (GIS), global positioning systems (GPS), remote and proximal sensing, data loggers, and geophysical instrumentation) and the development of statistical and geostatistical methods increased our capacity to collect, analyze, and predict soil information with a better accuracy substantially Brevik et al., 2016a). ...
... They are not concerned about the pedogenesis, and they are typically concerned about relatively small, local areas. On the other hand, scientists have also focused on the deep soil layers (Birmingham, 2003;Zuniga et al., 2013;Juilleret et al., 2016) and are typically interested in classification over much larger areas (Brevik and Hartemink, 2013). In some cases these comparisons are absolutely impossible since scientific taxonomies are based on soil genesis (French classification), laboratory criteria, and in several cases considered artificial as is the case with the FAO, WRB, and USDA classifications, since not all natural units are classified and similar types of soils can be classified incorrectly (Niemeijer and Mazzucato, 2003). ...
Chapter
Soil mapping is very important for the correct implementation of sustainable land use management. In recent decades, soil mapping methods and data availability have increased exponentially, improving the quality of the maps produced. Despite these advances, local knowledge is a great source of information, refined for centuries and useful for soil mapping and the implementation of a sustainable land management. Local wisdom and experience should be an important aspect of soil mapping because farmers will be one of the major end-users of the maps produced and they should account for the farmers’ reality. However, several problems have been identified in the spatial correlation between folk and scientific classification related to different cultural variables that influence local soil classification.
... In this work Shaler recognized that soil degradation was a problem that threatened human civilization and that tillage was a major cause of that degradation. In his writing Shaler clearly showed an appreciation for the importance of organisms in the creation of soils, but he also displayed the geologically-focused concept of soils that was common in the United States at the time (Simonson 1986;Brevik and Hartemink 2013) in his subdivisions of types of soils (e.g. cliff talus soils, glaciated soils, volcanic soils) and in his discussion of the influence of underlying rocks on soil properties in the section of the work titled "Inheritance". ...
... Men trained by these geology programs who went on to make significant contributions to soil science included Mark Baldwin, Hugh Hammond Bennett, George Nelson Coffey, Williamson E. Hearn, Francis Hole, Ralph McCracken, Thomas D. Rice and James Thorp (Brevik 2010). The U.S. Cooperative Soil Survey used classification systems with a heavy emphasis on geology through the first four decades of its existence (Brevik and Hartemink 2013). G. N. Coffey (Figure 4), trained by the geology program at the University of North Carolina, made an attempt to introduce Russian ideas concerning soils into the U. S. soil survey program starting in about 1908 (Brevik 1999). ...
Article
Despite the historical origins of soil science as a geological science, scholarship in the history of soil science remains an outlier with respect to the presently structured history of geological sciences community. The history-oriented activities of the Soil Science Society of America, the European Geosciences Union, and the International Union of Soil Sciences show active efforts to document and extend knowledge of soil science history. An overview of pedology and its numerous links to geomorphology and other geological specialties is presented. Geologists were involved in early soil mapping, soil degradation studies, creation of soil classification systems, and development of the soil geomorphology subfield, each case demonstrating strong historical ties between geology and soil science. Areas of common interest between soil science and geology offer new opportunities for integration and cooperation in Earth science history going forward.
... Soil maps date back to the early 1900s and primarily depicted the spatial distribution of various soils to aid understanding of this valuable natural resource (Brevik and Hartemink 2013;Hartemink et al. 2013). The value of soil maps has not changed significantly over the years. ...
Article
Full-text available
Although valuable for discovering geographical relationships and spatial statistics, bivariate maps or colour schemes are rarely employed in soil-related studies. For high-resolution mapping of the spatial relationships and patterns between the carbon-to-nitrogen (CN) ratio and its uncertainty throughout the Czech Republic, we assessed the application of a bivariate colour scheme. A random forest (RF) model was used to forecast CN ratio levels derived from the LUCAS topsoil dataset (n = 440 topsoil samples) using a stack of 22 environmental covariates. Of these covariates, Landsat 8 predictors (i.e. b6—SWIR 1 and b2—BLUE) had the highest relative value in the RF model. Additionally, partial dependence plots (PDPs) revealed that the aforementioned predictors had a comparable marginal impact on the CN model prediction. The 30 m × 30 m pixels CN ratio and uncertainty maps (at 0–20 cm) were able to distinguish the level contents evenly across the entire country while displaying distinct spatial features for each map. The uncertainty map and CN ratio prediction were both utilized to logically construct a bivariate colour scheme at 60 m × 60 m pixels, which enabled a once-off visualization of the two maps. The approach was deemed promising and proved generalizable for large-scale geographical evaluations in the focus area. Based on the output of the bivariate map visual, the spatial relationships and patterns between the CN ratio prediction and its uncertainty could be studied.
... 189 190 Soil mapping and soil classification are mutually dependent activities (McCracken and Helms, 1994), 191 therefore the quality of soil classification systems are closely related to the quality of soil mapping and 192 vice versa (Cline, 1977). For this reason, it is important that soil mapping and soil classification be 193 studied jointly when evaluating our understanding of soils (Brevik and Hartemink, 2013). Ideas about soil 194 classification changed considerably over the 20 th century in several countries, and dozens of countries 195 have their own classification systems. ...
Chapter
Basic soil management goes back to the earliest days of agricultural practices, approximately 9,000 BCE. Through time humans developed soil management techniques of ever increasing complexity, including plows, contour tillage, terracing, and irrigation. Spatial soil patterns were being recognized as early as 3,000 BCE, but the first soil maps didn’t appear until the 1700s and the first soil models finally arrived in the 1880s. The beginning of the 20th century saw an increase in standardization in many soil science methods and wide-spread soil mapping in many parts of the world, particularly in developed countries. However, the classification systems used, mapping scale, and national coverage varied considerably from country to country. Major advances were made in pedologic modeling starting in the 1940s, and in erosion modeling starting in the 1950s. In the 1970s and 1980s advances in computing power, remote and proximal sensing, geographic information systems (GIS), global positioning systems (GPS), and statistics and spatial statistics among other numerical techniques significantly enhanced our ability to map and model soils. These types of advances positioned soil science to make meaningful contributions to sustainable land use management as we moved into the 21st century.
... Nevertheless, the methodology of upscaling, that is, generalizing soil information collected at a large scale in a smaller scale map, can pursue diverse purposes and methodologies and therefore depict different images of the soil cover. For instance, generalized soil maps may be compiled to highlight either soil properties or processes (Brevik and Hartemink, 2013). ...
Article
Full-text available
Most small-scale soil maps report dominant typological units and allow only a partial appraisal of pedodiversity since territories with similar dominant soils can actually possess different pedodiversity. This is particularly true at the national scale, where a great wealth of soil information collected at more detailed scales is generalized.A methodology was set up, which aimed at preserving pedodiversity in upscaling soil maps by using geomatic techniques and the World Reference Base for soil resources (WRB). The main source of information was the soil system geodatabase of Italy, storing information of soil typological units and soilscapes at the 1:500,000 reference scale. Qualitative aggregation of soil taxa followed upscaling rules aimed at (i) maintaining the information about pedogenetic processes and (ii) grouping soilscapes showing recurrent patterns of soil forming processes. The upscaling methodology can be summarized in seven steps as follows: (1) soil forming processes selection, retrieved from soil typological units stored in the national database; (2) upscaling soil systems and creation of broad soil regions at 1:5,000,000 reference scale; (3) semantic upscaling of typological units to form taxa showing different soil forming processes; (4) ranking and associating soil forming processes; (5) geography upscaling of soil systems geometry to form polygons at 1:1,000,000 reference scale, called subregions; (6) ranking subregions according to their extension; (7) naming subregions by ranking the taxa according to the number of soil typological units.The soil subregion map reported 47 map unit and 148 taxa, belonging to 22 reference soil group of WRB and showing from one to four qualifiers. Each map unit had from 2 to 18 taxa, for a total of 317 occurrences. Thirty taxa had 3 or more occurrences, while the remaining took place in one or two subregions only. Diversity indices scored a very high Shannon's H'=5.35 on an H max =5.76 for the whole country. The value of the Evenness index (E) was 0.93. The map of Shannon's H highlighted that the highest pedodiversity in Italy is preserved in the northernmost part of the Alps, in the coastal plains of Central and Southern Italy, and in some hilly lands of Central Italy. On the other hand, large plains of Northern Italy and mountainous areas of the Central and Southern Italy keep low pedodiversity. The comparison of the results with studies on vegetation diversity and land degradation and desertification suggested the existence of linkages between pedodiversity, biodiversity, and the current and past management of agricultural and forest ecosystems.
... Eagle's world was also without boundaries, spanning the continent and the globe. Eagle was unburdened by Turtle's taxonomic and class-based conventions, so Turtle's discussions with Eagle were like turning back the pages of time (Brevik and Hartemink, 2013). Eagle asked many questions related to the extent of certain soils, the relationship of soils mapped in association with each other, and the use of soil survey information for revealing patterns in how the "skin" of the earth functions. ...
... Note the sudden increase in the number of soil series as Soil Taxonomy was adopted in the mid-1960s. Figure originally published in Brevik and Hartemink (2013), courtesy of Dylan Beaudette, USDA-NRCS, California Soil Resource Lab. ...
... The first attempts at soil mapping occurred in Europe in the early 1700s (Brevik et al., 2016a), while the first modern soil map was produced in 1883 (Brevik and Miller, 2015). The study of these early maps is important as they serve as primary sources that allow us to understand the past status of our knowledge of various environmental subjects and how that knowledge has evolved over time (Edney, 2005;Brevik and Hartemink, 2013). ...
... In this context, the production of soils maps based on soil-forming processes (Brevik & Hartemink, 2013;Ubalde, Sort, & Poch, 2011) can easily take into account soil factors relevant to irrigation system design and improvement. Describing and naming soils according to standard and widely accepted criteria, for example, Soil Taxonomy (Soil Survey Staff, 1999) enables the sharing of experience and the information exchange needed when dealing with new irrigation technologies. ...
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Irrigation is needed for profitable agriculture in the central Ebro valley, one of the driest regions in Europe. In this region, aridity and outcrops of saliferous strata induce soil salinity in some irrigated districts. We present a soil map of two municipalities (about 32 km²) coping with soil salinity and currently changing their irrigation from flood to pressurized systems. The 1:25,000 scale map displays 27 Soil Series following the Soil Taxonomy approach and records local pedodiversity for the first time. The scale of the map and its delineation on orthophotographs enables users to locate each agricultural plot (typical size ∼1 ha) and to assign the soil information relevant for irrigation, and then a Soil Phase for salinity. Saline soils occur in irrigated areas totaling 24% of the total surface of the two municipalities studied. The salinity mapping plus other soil features used for map unit definition (texture, stoniness, and available water holding capacity), allow recommendations about the design of irrigation system enhancements.
... The idea of zonal soils has been long-discredited due to over simplicity. For example, the United States can be represented by Pedalfers in the humid east and Pedocals in the arid west with a division roughly along the Mississippi River (Brevik and Hartemink, 2013). This was incorrect because Pedocals were not characterized by climate but limestone which was also found in the east of the U.S. (Paton and Humphreys, 2007). ...
... The first attempts at soil mapping occurred in Europe in the early 1700s (Brevik et al., 2016a), while the first modern soil map was produced in 1883 (Brevik and Miller, 2015). The study of these early maps is important as they serve as primary sources that allow us to understand the past status of our knowledge of various environmental subjects and how that knowledge has evolved over time (Edney, 2005;Brevik and Hartemink, 2013). ...
... With large databases being available, there are plenty of observations on soil erosion in some areas, while data on others is scarce (Brevik et al., 2013). To understand the patterns of sediment delivery at the hillslope scale, one needs information on the spatial distribution and magnitudes of erosion and deposition (Royall, 2001). ...
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Magnetic measurements of soils are an effective research tool in assessing soil erosion. This approach is based on detecting layers showing different magnetic properties in vertical soil profiles and lateral catenas. The objective of this research is to compile data on magnetic susceptibility (MS) of soils in Eastern Ukraine to assess the soil erosion rates. The chernozems of Tcherkascy Tishki (Kharkov Region, Ukraine) have undergone a field crop rotation without proper soil conservation technologies being applied. We conducted an intrinsic element grouping of the magnetic susceptibility values and demonstrated that they can be used as MS cartograms in soil erosion mapping. The study showed a strong correlation between the MS values and the erosion index. MS and the erosion index were found to correlate with the humus content. Magnetic mineralogical analyses suggest the presence of highly magnetic minerals (magnetite and maghemite) as well as weakly magnetic goethite, ferrihydrite, and hematite. Stable pseudosingle-domain (PSD), single-domain (SD), and superparamagnetic (SP) grains of pedogenic origin dominate in the studied chernozems. Being an effective, quick and low cost alternative, magnetic methods can be successfully used in the soil erosion investigations.
... The technologies of digital soil mapping have been developed in many countries-Australia [70], America [49], the Netherlands [60], Denmark [39,57], France [42], Russia [4,8,12,20,28], and others-for several decades. They are also applied at the global level [41,42]. ...
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The main trends in the development of soil mapping methods are discussed, and the major problems are identified. By the present time, the transition from the paper-based soil maps to digital soil-geographical databases has already been completed. The digital mapping of soils and their properties is now accepted as the main method at all the levels of generalization. The approaches of digital soil mapping, as well as of the traditional one, are based on the ideas of V.V. Dokuchaev about the dependence of soils on soil-forming factors. However, in digital soil mapping, new achievements of mathematical statistics and mathematical modeling are being widely applied. This provides for a greater objectivity and reproducibility of the digital soil maps in comparison with the traditional soil maps. At the same time, all unsolved problems of soil cartography related to the lack of field observation data, scale, soil taxonomy, spatial microheterogeneity, and mapping of individual soil properties are preserved. Partially, these problems can be solved by using remote sensing data. When the soil geographical information is used to assess the quality of soil resources, the interpretation of remote sensing data for mapping purposes seems to be more preferable in comparison with the methods of digital soil mapping. Full text is available via link: https://rdcu.be/bO80g
... Classification simplifies the complexity and continuum that exist in soils. The process of classification systematically utilizes knowledge of pedogenesis to arrange soils on the basis of their characteristics (Brevik and Hartemink, 2013), enclosing more similar (homogeneous) units while separating dissimilar (heterogeneous) ones to facilitate sustainable utilization and management. USDA keys to soil taxonomy hierarchically grouped soils into six taxonomic categories with series at the lowest level (Guo et al., 2003). ...
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Variability in soil properties is a critical element for agronomic and environmental decision making processes. This study therefore assessed the extent of spatial dependence and spatial structure of particlesize distribution in 0.49 hectares of land and their implications on pedogenesis and management of basement complex soils of southwestern Nigeria. A total of forty-nine (49) surface soil (0 – 15 cm) samples were collected at 10 m2 rigid grid (node) intervals in a plot under fallow at University of Ibadan Teaching and Research Farm, Ibadan. Classical statistics (including statistics of dispersion, test of normality andcorrelation analysis) and geostatistics were adopted in evaluation of spatial variability of soil particle size distribution. The results of coefficient of variation indicated that sand, and coarse sand contents were leastvariable (<15%), silt and silt + clay were moderately variable (>15<35%), whereas clay, fine sand contents and silt clay ratio were highly variable (>35%). Spatial dependence of the soil separates indicated that clayand coarse sand had 16.6% and 24.6%, respectively and were strongly spatially dependent. Moderately spatially dependent soil properties included silt (46.5%), fine sand (59.7%), silt + clay (54.4%) and SCR(52.9%), while total sand (93.6%) was weak. The Pearson correlation coefficients of the semivariances indicated significant relationships between sand and silt + clay (r = -0.99, p<0.01), and silt and silt clay ratio (r = 0.77, p<0.01). It was observed that clay, sand and silt + clay bear similar distribution in the field as shown by the prediction contour maps. These variables could receive similar treatment in precision farming, enhance knowledge of pedogenesis and sustainable environmental management.
... Classification simplifies the complexity and continuum that exist in soils. The process of classification systematically utilizes knowledge of pedogenesis to arrange soils on the basis of their characteristics (Brevik and Hartemink, 2013), enclosing more similar (homogeneous) units while separating dissimilar (heterogeneous) ones to facilitate sustainable utilization and management. USDA keys to soil taxonomy hierarchically grouped soils into six taxonomic categories with series at the lowest level (Guo et al., 2003). ...
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The study classified the coastal plain sands of south-eastern Nigeria at the series level and modeled the classification using digital terrain attributes. The study utilized 72 secondary and 12 primary profile pits data generated from 24 and 4 locations (at 3 per location) for classification/modelling and validation respectively. The three profile pits per location represents the three topographic positions of upper, middle and lower slopes. Digital elevation model was also utilized for the generation of terrain attributes. Soil morphological characteristics were coded for suitability in statistical analysis. Hierarchical clustering was utilized in the grouping of the soil into 17 homogeneous groups referred to as soil series. Regression kriging was used to model the predicted soil series within the area covered by coastal plain sands in Akwa Ibom State. The variables that could be used in the modelling of the different classified soil series include Sand Content, aspect, flow accumulation, compound topographic index (CTI), elevation, hill shade, slope, curvature, flow direction, stream power index (SPI), profile curvature, tangential curvature (R2 = 0.21).Out of the 17 soil series classified, 14 was successfully mapped using digital technique. It was observed that 66.7% of the classified soil series were accurately predicted using digital mapping technique. The classifications carried out numerically made use of morphological discrete variables whereas digital used empirically determined continuous variables which could be more accurate. Therefore it could be inferred that the digitally produced soil classification is more accurate and 14 soil series could be identified and mapped in the study area. Key words: pedogenesis, digital soil mapping, soil series, hierarchical clusters, regression kriging
... Soil series is also a useful taxonomic category to describe pedodiversity regarding ES/ED at more detailed scales (e.g., farm and field), and this category is closely allied to interpretive uses (e.g., suitabilities and limitations for crop production and construction) ( Table 7). Soil series consist of pedons that are grouped together based on similarity in pedogenesis, soil chemistry, and physical properties [38]. The number of soil series within the soil extent can describe its diversity (Table 7). ...
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Soil ecosystem services (ES) (e.g., provisioning, regulation/maintenance, and cultural) and ecosystem disservices (ED) are dependent on soil diversity/pedodiversity (variability of soils), which needs to be accounted for in the economic analysis and business decision-making. The concept of pedodiversity (biotic + abiotic) is highly complex and can be broadly interpreted because it is formed from the interaction of atmospheric diversity (abiotic + biotic), biodiversity (biotic), hydrodiversity (abiotic + biotic), and lithodiversity (abiotic) within ecospheres and the anthroposphere. Pedodiversity is influenced by intrinsic (within the soil) and extrinsic (outside soil) factors, which are also relevant to ES/ED. Pedodiversity concepts and measures may need to be adapted to the ES framework and business applications. Currently, there are four main approaches to analyze pedodiversity: taxonomic (diversity of soil classes), genetic (diversity of genetic horizons), parametric (diversity of soil properties), and functional (soil behavior under different uses). The objective of this article is to illustrate the application of pedodiversity concepts and measures to value ES/ED with examples based on the contiguous United States (U.S.), its administrative units, and the systems of soil classification (e.g., U.S. Department of Agriculture (USDA) Soil Taxonomy, Soil Survey Geographic (SSURGO) Database). This study is based on a combination of original research and literature review examples. Taxonomic pedodiversity in the contiguous U.S. exhibits high soil diversity, with 11 soil orders, 65 suborders, 317 great groups, 2026 subgroups, and 19,602 series. The ranking of “soil order abundance” (area of each soil order within the U.S.) expressed as the proportion of the total area is: (1) Mollisols (27%), (2) Alfisols (17%), (3) Entisols (14%), (4) Inceptisols and Aridisols (11% each), (5) Spodosols (3%), (6) Vertisols (2%), and (7) Histosols and Andisols (1% each). Taxonomic, genetic, parametric, and functional pedodiversity are an essential context for analyzing, interpreting, and reporting ES/ED within the ES framework. Although each approach can be used separately, three of these approaches (genetic, parametric, and functional) fall within the “umbrella” of taxonomic pedodiversity, which separates soils based on properties important to potential use. Extrinsic factors play a major role in pedodiversity and should be accounted for in ES/ED valuation based on various databases (e.g., National Atmospheric Deposition Program (NADP) databases). Pedodiversity is crucial in identifying soil capacity (pedocapacity) and “hotspots” of ES/ED as part of business decision-making to provide more sustainable use of soil resources. Pedodiversity is not a static construct but is highly dynamic, and various human activities (e.g., agriculture, urbanization) can lead to soil degradation and even soil extinction.
... Famous early soil researchers who were trained as geologists include F.A. Fallou, V.V. Dokuchaev (Krupenikov, 1992), C.F. Marbut (Tandarich and Sprecher, 1994), C.R. Darwin (Herbert, 2005), T.C. Chamberlain (Hartemink et al., 2012), and J. van Baren (Hartemink and Sonneveld, 2013). Because geologists were the primary scientists mapping landscape features, many early soil maps were basically surficial geology maps, and early soil classification systems and map units were based on the underlying geology rather than the properties of the soil (Brevik and Hartemink, 2013; Miller and Schaetzl, 2014). ...
Article
The first soil maps were made by geologists and many early soil maps were surficial geology maps. After soil science became established as a scientific discipline, there has been a continued interplay between geologists and soil scientists, both fields benefiting from advancements made by the other. In the 1940s and 1950s, researchers began to use soil information or soil maps to assist in the improvement or construction of various types of geologic maps. There is strong agreement between preliminary geology maps created from soil maps and traditional geology maps. This is primarily due to the influence of parent material on soil formation, and may also be due in part to the importance placed on parent material in some soil classification systems. Despite the results obtained when using soil maps to create surficial geology maps, there is a need for more quantitative studies to assess the degree of compliment between soil-based maps and traditional geology maps, expansion of the technique into a wider range of geologic and climatic environments, and more research in locations that use classification systems other than Soil Taxonomy.
Article
The historical development of state general soil maps is examined over the time intervals of pre-1927, 1927–1960, 1960–1999, and post-1999, which correspond to major periods in the development of soil classification schemes in the USA. Eleven states developed general soil maps prior to the development of the country's first soil classification scheme in 1927, and these were created for agriculture and based primarily on soil-physiographic provinces. Twenty states prepared general soil maps during the period in which zonal soil classification schemes were employed (1927–1960). Although physiography continued to be a primary basis of soil mapping, soil associations were used in 56% of the maps. The time period between the publication of the Seventh Approximation (1960) and the second edition of Soil Taxonomy (1999) was the “golden era” for general soil maps, with 46 states (92%) making them available to the public in hardcopy format, primarily as soil series-association maps. There was a dramatic reduction in the generation of state soil maps from 1999 to 2014 (to 22 states), largely because of the digital age. Individuals with GIS expertise were encouraged to develop their own maps using STATSGO and SSURGO databases. Initiated in 2005 the Web Soil Survey has enabled the public to produce maps for areas of less than 40,500 ha. The level of detail in state soil maps has increased over time, but soil-series association maps remain a popular venue. General maps using Soil Taxonomy provide valuable information regarding the nature, properties, and soil-forming factors and processes of soils, as well as their geographic distribution. General state maps remain important as a natural resource data layer and for instructional purposes.
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Soil maps depict the distribution of soils on the earth's surface and have an important role in aggregating our knowledge of soil resources. The maps are based on geographic rules of spatial arrangement of soils and at each scale show soil distribution patterns. Here we review how world soil maps have evolved from the early 1900s to the present. The first world soil map was published in 1906 by K.D. Glinka and included 18 soil classes that more or less corresponded to the climatic zones of the Earth. This first map was followed by a number of world soil maps at various scales developed in different countries. With increasing informa-tion following extensive soil surveys in all parts of the world, world soil maps have become more precise, less schematic and eventually have led to the FAO–UNESCO soil maps. Over time, world soil maps show an in-creasing complexity of the depicted soil pattern but most of the maps were concept-dependent rather than data-derived and are influenced by the underlying systems of soil classification. In recent years, a project in soil mapping was developed that is based on the mapping of key soil properties rather than soil classes (GlobalSoilMap project). In the future, world soil maps should include both soil classes and soil properties and be accompanied by a set of interpretative tools. Published by Elsevier B.V.
Article
The Seventh Approximation emerged in 1960, and the first edition of Soil Taxonomy was published in 1975. Through the years, as intended in its original architecture, revisions have been made at all levels in the system. This has resulted in the addition of two new orders and a multitude of classes at other categorical levels. Four distinct and contrasting periods can be identified and described with regard to the magnitude of changes in taxa at various levels. The most dramatic changes occurred between the mid-1980s and publication of the second edition of Soil Taxonomy, when numerous international committees that had been charged with investigating particular taxonomic questions were completing and publishing their final reports and findings. Not surprisingly, most of these revisions resulted in the addition of taxonomic classes, although occasionally (especially in the 1998 Keys to Soil Taxonomy) there were notable reductions in the number of classes within certain orders. This review documents the nature and magnitude of changes that have occurred in the development of the US soil taxonomy during its 54-yr history to provide a context within which to better understand how the current state of our soil classification system has evolved.
Article
We review historical soil maps from a geographical perspective, in contrast to the more traditional temporal-historical perspective. Our geographical approach examines and compares soil maps based on their scale and classification system. To analyze the connection between scale in historical soil maps and their associated classification systems, we place soil maps into three categories of cartographic scale. We then examine how categories of cartographic scale correspond to the selection of environmental soil predictors used to initially create the maps, as reflected by the maps' legend. Previous analyses of soil mapping from the temporal perspective have concluded that soil classification systems have co-evolved with gains in soil knowledge. We conclude that paradigm shifts in soil mapping and classification can be better explained by not only their correlation to historical improvements in scientific understanding, but also by differences in purpose for mapping, and due to advancements in geographic technology. We observe that, throughout history, small cartographic scale maps have tended to emphasize climate-vegetation zonation. Medium cartographic scale maps have put more emphasis on parent material as a variable to explain soil distributions. And finally, soil maps at large cartographic scales have relied more on topography as a predictive factor. Importantly, a key characteristic of modern soil classification systems is their multi-scale approach, which incorporates these phenomena scales within their classification hierarchies. Although most modern soil classification systems are based on soil properties, the soil map remains a model, the purpose of which is to predict the spatial distributions of those properties. Hence, multi-scale classification systems still tend to be organized, at least in part, by this observed spatial hierarchy. Although the hierarchy observed in this study is generally known in pedology today, it also represents a new view on the evolution of soil science. Increased recognition of this hierarchy may also help to more holistically combine soil formation factors with soil geography and pattern, particularly in the context of digital soil mapping.
Chapter
A large part of scientific knowledge about soils has come from orderly and refined laboratory analysis and interpretation, the development and testing of sound theory, the adoption and modification of practices and procedures from the other sciences, and countless soil surveys across all parts of the globe. Some knowledge was gained by chance, but most was won through systematic studies.
Article
This is a book about soils of the United States. Soils are a critical and often unappreciated resource because they are belowfoot and mostly out of sight. This book brings to you a comprehensive overview of the diversity, beauty, and vital importance of soils to ecosystems, agriculture , forestry, and urban infrastructure. It is intended to be a reference and learning tool that will enhance your knowledge, understanding, and appreciation of the soil resources in the USA. Soil supports all terrestrial life forms, and performs functions critical to the well-being of the global population including nutrient and water storage and supply for plant growth, partitioning of precipitation into ground and surface waters, disposal and renovation of anthropogenic wastes, habitat for soil organisms, and support for roads, buildings, and other infrastructure. Soils are a major reservoir of global carbon and can, with proper management, serve as a sink for atmospheric carbon to reduce greenhouse gasses. Soils are relatively resilient, but are subject to degradation if managed improperly. Only by understanding the properties of and processes occurring in the soil, can the soil resource be conserved and sustained for continued support of the Earth’s population.
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В съществуващите научни изследвания са останали неосмислени теми и въпроси от гледище на правната наука. Това е най-вече вярно за юридическите аспекти на депортацията на вардарските, беломорските и пиротски евреи, за които, доколкото изобщо има анализи, те не са правни, често са вътрешно противоречиви и недостатъчно обосновани. Затова може да бъде подкрепен изводът на Надя Данова, че правните аспекти на този проблем са само „частично осветлени“ . Стремежът да се даде отговор, макар и частичен, на необходимостта от допълнителни правни изследвания на тази проблематика е в основата на този труд. Задачата на изследовател, избрал да проучва сложни обществени процеси и явления през призмата на тясната си научна специалност, рискува неуспех или в по-добрия случай повърхностно наблюдение. Особено в правните изследвания, старателното проучване на нормативни актове, съдебни решения и административна практика често създава строго фактографски проучвания, детайлно описващи документи и факти, но без аналитични изводи и дълбочина. Така се постига единствено “фрагментирана историческа истина” . Да се обхванат обаче всички политически, обществени, дипломатически и други предпоставки, повлияли на волята на законодателя и предопределили правоприлагането в определен исторически период, е непосилна задача. Действително, сложни обществени явления е невъзможно да бъдат обяснени само с един или два фактора. И все пак, струва ми се, юристът, без да подценява комплексните причини зад обществените процеси и ролята на историческите случайности, трябва да ги остави настрана в достатъчна степен, за да може да представи в разбираем вид правния анализ на изучаваните от него явления. Именно поради неизбежното ограничение на научната дисциплина редица фактори, повлияли при вземане на законодателните и управленски решения на властите в Царство България, които са обект на изследване от други науки – историография, социология, политология, теория на международните отношения, тук са само маркирани. От друга страна, в стремеж да не се свежда изследването до инвентаризация на нормите и правоприлагането, е използван правно-исторически метод, който не е затворен само в правните актове, а разчита на плурализъм на източниците и бриколажни, разнородни перспективи . По тази причина, редом с нормативните актове, съдебните решения и административната практика, в това съчинение са търсени и по-общи източници на интелектуалната и социална история като трудове на учени от периода, политически изказвания, мемоари на съвременници и др.
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Introducción La medición de la cultura organizacional responde a la necesidad de identificar aquellos aspectos que la dirección requiere afianzar para obtener mejores resultados de gestión. El propósito de esta investigación fue diseñar y validar la Escala de Diagnóstico de la Cultura Organizacional (EDCO) para organizaciones mexicanas de tamaño mediano. Método Se realizó el diseño a partir de la revisión teórica, se validó mediante un panel Delphi con ocho expertos y una prueba piloto en 261 trabajadores pertenecientes a cinco empresas medianas. Resultados Se analizó la comprensibilidad, validez del contenido y de constructo. La validación por los expertos se consideró adecuada y en la prueba piloto, la escala obtuvo un alfa de Cronbach de 0.961. El análisis factorial exploratorio permitió identificar siete factores que explican el 52.1% de la varianza. Los factores finales son identidad, normas, involucramiento con el propósito, creación de cambio, enfoque al cliente, trabajo en equipo y búsqueda del bienestar social. Discusión o Conclusión Se confirma que la versión final del instrumento presenta una alta confiabilidad y validez, se puede utilizar para valorar la cultura organizacional desde la percepción de los trabajadores, identificando aquellos aspectos a mejorar mediante procesos de intervención organizacional, así como aquellas prácticas que permean positivamente en los propósitos de las organizaciones mexicanas.
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El suelo es un cuerpo natural muy importante para el desarrollo de cultivos y especies vegetales, debido a que provee el soporte a las raíces de las plantas, además aporta nutrientes para su desarrollo y producción, dependiendo del tipo de suelo y sus propiedades. Conocer y cuantificar los suelos es necesario para planear las actividades agrícolas, pecuarias, forestales, urbanas, mineras y de conservación. Los objetivos del presente trabajo fueron: 1) actualizar la cartografía edafológica 1:50 000 por municipio del Estado de México; y 2) cuantificar la superficie de los suelos y conocer su ubicación para identificar áreas de reconversión productiva. La cartografía se generó con la digitalización de las cartas edafológicas escala 1:50 000, con un sistema de información geográfica (SIG), se generó su base de datos: suelos primarios, suelos secundarios, fase física, fase química y textura; esta base de datos se actualizó a la versión de suelos 2015 de la WRB. Los suelos con mayor superficie y más productivos son: Andosoles con 479 908 ha, Feozems con 472 718 ha, Vertisoles con 241 485 ha y Cambisoles con 196 047 ha. Estos predominan en los municipios de Aculco, Toluca, Acambay, Jilotepec, Axapusco, Ixtlahuaca y Almoloya de Juárez.
Article
Rapid cropland reformation is occurring in the cold region of China (hereafter referred to as Cold China), affecting national crop structure production. In addition, different agricultural systems, including state and private farms, exist in Cold China. To date, the different effects of cropland reformation on grain production in state and private farms are lacking. Focusing on this issue and using synergistic methodology, results revealed that the transformation from upland crops to paddy field was principal land change across Cold China from 1990-2015. This transformation increased grain production by 434.0×10⁴ t, accounting for over 14.0% of the total grain production increase in Cold China (i.e., from 748.0×10⁴ t in 1990 to 3785.1×10⁴ t in 2015) in the study period, showing positive feedback on grain security. Between two agricultural systems, more intensive transformation area (10993.3 km² vs. 4673.5 km²) and a larger contribution to grain production increase (11.1% vs. 3.2%) occurred on state compared with private farms. Crop structure also evolved differently in the two agricultural systems. Dominant crop changed from soybean (1990-2000) to rice paddy (2000-2015) on state farms but from soybean (1990-2005) to corn (2005-2015) on private farms, indicating state farms focused on human dietary supply and private farms mainly served industrial needs. This study showed cropland reformation in response to global food trade increased grain production in Cold China. State farms were more efficient in such reformation; more market-oriented policies should be designed to encourage the reformation on private farms. This study provided a new reference for other regions/countries’ investigation on cropland and food structural security in different agricultural systems.
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The first half of the twentieth century was turbulent. There was panic in the early 1900s with a stock market crash, followed by the First World War in 1914, and the revolution in Russia in 1917.
Article
The early 1900s were a time of rapid growth in American soil science. Edward Elway Free is not well known but produced some excellent work during this time. Free majored in Chemistry at Cornell University and graduated in 1906. He worked as a chemist with the University of Arizona from 1906-1907, as a physical scientist with the Bureau of Soils from 1907-1912, and as a private consultant in chemistry and physics after 1912. In 1917 Free earned a Ph.D. from Johns Hopkins University. He continued to run his consulting company until his death on November 24, 1939. Publication trends over Free’s career include publications in chemistry (1908-1910), eolian processes and soil physics (1909-1912), and economic resources (1912-1917). After 1917 his agriculturally related publications were in soil aeration and weather and climate.
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A broad interpretation and survey to pedological concepts of soils as developed over the years and the relationship between these concepts and classification. The role of these concepts in soil survey is also explored. -K.Clayton
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Several discontinuous, fragmented strandlines exist along what formerly was the western shoreline of glacial Lake Agassiz in Grand Forks County, North Dakota. Their fragmented nature makes mapping and correlation of these strandlines difficult. We have attempted to better define one of these strandlines, the Norcross, through the use of soil maps in the Soil Survey of Grand Forks County. Preliminary results of this study indicate that combinirig information from geological and soil maps could provide a means to bet-ter define poorly preserved landforms. Fieldwork is now needed to further support or refute these preliminary results. As topography and parent material are two of the soil-forming factors, soil scientists also stand to benefit from accurate geological maps. Given that each profession has the potential to benefit from the improved mapping of the other, it seems reasonable to suggest that there should be ongoing cooperation between parties mapping the geology and the soils in a common area. Lake Agassiz began to form against the retreating Red River Lobe of the Laurentide Ice Sheet about 11 700 years before the present (YBP) (Teller, 1990; Fenton et al., 1983), in a depression caused by the weight of the ice (Brevik, 1994, unpublished data). As the lake level fluctuated as a result of advances and retreats ofthe ice sheet, downcutting, and postglacial rebound, several strandlines (including beaches) were formed along Lake Agassiz's shores (Fig. 1). The pre-served sections of the strandlines tend to be slightly higher than the surrounding landscape (Brevik, 1997), usually about 5 to 25 ft (Bluemle, 1991), and in Grand Forks County trend to the north-northwest (Hansen and Kume, 1970). Many of these strandlines occur as discontinuous segments, often less than 3 mi long, and because of this it is difficult to trace and correlate them (Bluemle, 1991). One of these poorly preserved, fragmented strandlines is the Norcross. Grand Forks County, North Dakota, was chosen as our study area (Fig. 2). This county is ideal for this study for a number of reasons: (i) strandlines are eas-ily distinguishable from other landforms on soil maps; (ii) several strandlines have been clearly mapped by the North Dakota Geological Survey here, making it easy to locate and differentiate a number of strandlines; and (iii) several of the strandlines in the county are highly fragmented (Bluernle, 1991; Hansen and Kume, 1970).
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recently published a paper documenting the accomplishments of George Nelson Coffey (Brevik, 1999). Some of the information I found on Coffey during my research was not presented in my original paper for a variety of reasons. Since the publication of my first article, I have also established contacts with a number of people that have resulted in my acquiring additional information and/or insights on Coffey. This is not intended to be a complete recount of Coffey's work in soils; information from Brevik (1999) will be duplicated here only as needed to establish historical timelines and provide continuity. The reader is referred to Brevik (1999) fora more complete discussion of Coffey and his work. George Nelson Coffey (Fig. 1) was born on 17 Jan. 1875 in Patterson, NC to Elijah and Mary Ann (Nelson) Coffey (Marquis, 1924), the fourth offivechil-dren {Ancestry. com, 2001). He received a Bachelor of Philosophy degree from the University of North Carolina (UNC) cum laude in 1900, concentrating on geology and chemistry (Brevik, 1999). Coffey proceeded from UNC to the Bureau of Soils, arriving in time for the Bureau's second season of fieldwork (Brevik, 1999). Coffey worked his way up through the ranks at the Bureau, serv-ing as a Field Assistant from 1900 to 1904, then in charge of soil classification from 1905 to 1909, and finally serving as the head of the Bureau of Soils Great Plains Division from 1909 to 1911 (Brevik, 1999). Coffey authored or coauthored a number of publications during his 11 yr with the Bureau of Soils, including at least 17 soil surveys (Holman et al., 1939). Some of these soil surveys were particularly good works for their time. Roy Simonson wrote to me that he first became interested in Coffey when working in Ames, lAin the early 1940s. Dr. Simonson was working on a soil survey of Tama County with Andy Aandahl, and after completing their own work they decided to compare their general map to the previous Tama County soil survey (Ely et al., 1905). Dr. Simonson wrote, "After seeing what had been done in 1904, I con-cluded that one or the other of the three men who made that survey was ahead of his time" (written communication, 29 Feb. 2000). Further investigation by Dr. Simonson turned up no additional works by Griffin, only other soil surveys by Ely, but a number of scientific papers in the case of Coffey, including his now famous Bulletin 85. Although it cannot be said with certainty that the items found to be outstanding by Dr. Simonson in the first Tama County survey were due to Coffey's influence, that is one likely explanation. While the degree of influence Coffey may have had over individual soil surveys is uncertain, without question Coffey produced a number of outstanding scientific papers during his time at the Bureau of Soils. Several of these, includ-ing Bulletin 85 (Coffey, 1912), are discussed in Brevik (1999) and won't be dis-cussed here. However, one paper written by Coffey during his time at the Bureau of Soils deserves more attention than it has been given. The paper was based on
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Legacy soil maps are an important input in digital soil mapping. This paper traces how reconnaissance soil maps in Wisconsin evolved between the 1880s and the present with some discussion on future directions. The first soil map in the USA was made in Wisconsin by the geologist T.C. Chamberlin in 1882. The second soil map of Wisconsin was made by A.R. Whitson in 1927, and the third by F.D. Hole in 1976. Soil texture and physiography were the major diagnostic mapping criteria. As more detailed county soil surveys were completed and knowledge of the soils increased, a higher level of detail can be observed on statewide soil maps. The detailed county soil maps were digitized in the 1990s and early 2000s and have been used in a wide range of studies and applications (e.g. agriculture, forestry, landscape architecture, and human health). In the 1990s, soil scientists transitioned from mapping on paper copy aerial photos to digital procedures. This change coincided with the development of digital soil mapping, and the introduction of several new observational techniques (GPR, EMI, and cone penetrometer). These modeling and observational tools continue to be used to evaluate small areas, but have not yet become widely used for current soil mapping activities.
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George Nelson Coffey joined the Bureau of Soils in 1900, the second year of its existence, and worked in the program for about 11 years. During those years he worked on soil surveys in many parts of the United States. Those surveys exposed him to a wide variety of soils. Because of his experience and knowledge, he was chosen to supervise soil classification and correlation after five years with the Bureau. During the time that he was in charge of soil classification and correlation, Coffey became acquainted with earlier soil studies such as those of E. W. Hilgard in Mississippi, T. C. Chamberlain in Wisconsin, and the Dokuchaiev school in Russia. From those sources and his own field experience, Coffey developed and promoted his ideas of soil genesis and classification. Coffey’s ideas were in marked contrast to the prevailing idea in this country that soils were simply a function of the underlying rocks. Coffey presented his ideas in journal articles for several years, culminating with the publication of USDA Bureau of Soils Bulletin No. 85 in 1912. Bulletin 85 is now recognized as a classic, but like Coffey’s journal articles, it fell on deaf ears in 1912. Coffey left the soil survey program before Bulletin 85 was published and worked at the Ohio Agricultural Station where he worked on soil mapping, an erosion study, and fertilizer trials. Later, Coffey moved on to the University of Illinois. By 1922 Coffey left soil science as a career but retained his interest in soils and geology. After leaving the soil survey program Coffey’s publications on soil genesis and classification were largely forgotten.
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The development of soil classification and mapping by the USDA Soil Survey up to 1935 is considered. This involved the initial development of a scheme by Whitney based on soil productivity as reflected in the geology cum geomorphology. The thrust of this development was opposed by a very different Russian zonalistic approach, which was much more environmental in character. It was first advanced in the USDA by Coffey, but this was firmly rejected by Whitney. It was next proposed by Marbut, who in addition made use of Glinka's work, but made no references to Coffey's previous efforts. This was highly successful, for it not only took over the USDA system completely, but was expanded to form a global system of soil classification. However, the speed with which this occurred was such that numerous flaws and gaps had been created, which needed to be dealt with and this is considered in Part II.
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IntroductionDevelopment of Soil InterpretationsSoil Interpretations-Mixed ReceptionsInterpretations TodayFederal and State ProgramsState and Local PlanningNatural Resource ManagementHistoric Site IdentificationReal Estate and InsuranceEngineering and ConstructionMilitaryHazardous Waste, Brownfields, and RemediationResearch and InvestigationsLooking AheadReferences
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Modern soil taxonomic systems, including Soil Taxonomy ST and the World Reference Base Ž . WRB for Soil Resources, classify soils using diagnostic horizons, properties, and materials. Although these systems are based on genetic principles, the approaches used have de-emphasized the role of soil processes in soil taxonomic systems. Meanwhile, a consideration of soil processes is important for understanding the genetic underpinnings of modern soil taxonomic systems and developing quantitative models of pedogenic systems. Seventeen generalized soil-forming pro-cesses are identified, briefly discussed, and linked to soil taxa and diagnostic horizons, properties, and materials in ST and the WRB. The processes are illustrated in simple diagrams and include: Ž . Ž . Ž . Ž . 1 argilluviation, 2 biological enrichment of base cations, 3 andisolization, 4 paludization, Ž . Ž . Ž . Ž . Ž . 5 gleization, 6 melanization, 7 ferrallitization, 8 podzolization, 9 base cation leaching, Ž . Ž . Ž . Ž . Ž . Ž . 10 vertization, 11 cryoturbation, 12 salinization, 13 calcification, 14 , solonization, 15 Ž . Ž . solodization, 16 silicification, and 17 anthrosolization. The implications of soil-forming processes on present and future soil classification systems and pedogenic models are discussed. q 2000 Elsevier Science B.V. All rights reserved.
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Several discontinuous, segmented strandlines that mark the former shores of Lake Agassiz can be found in eastern North Dakota. These strandlines are difficult to map and correlate because of their segmented nature. Better mapping would benefit researchers working on a number of problems involving Lake Agassiz including dating the strandlines, reconstructing the lake''s history, and calculation of asthenosphere viscosity beneath the Lake Agassiz basin. Elongated soil delineations representing beach-indicative soils with a north-northwest trend and extending from currently mapped areas of the Herman strandline were identified on Grand Forks County soil maps. This information was combined with the geologic map of Grand Forks County in an attempt to better define the location of the Herman strandline in the southern part of the county. This approach worked well, and it is recommended that similar studies be attempted on other Lake Agassiz strandlines in North Dakota and the surrounding area.
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Soils knowledge dates to the earliest known practice of agriculture about 11,000 BP. Civilizations all around the world showed various levels of soil knowledge by the 4th century AD, including irrigation, the use of terraces to control erosion, various ways of improving soil fertility, and ways to create productive artificial soils. Early soils knowledge was largely based on observations of nature; experiments to test theories were not conducted. Many famous scientists, for example, Francis Bacon, Robert Boyle, Charles Darwin, and Leonardo da Vinci worked on soils issues. Soil science did not become a true science, however, until the 19th century with the development of genetic soil science, led by Vasilii V. Dokuchaev. In the 20th century, soil science moved beyond its agricultural roots and soil information is now used in residential development, the planning of highways, building foundations, septic systems, wildlife management, environmental management, and many other applications in addition to agriculture.
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Soil maps can be used to generate maps showing the areal distribution of bedrock. This technique is especially useful in heavily vegetated areas where weathering is intense and outcrops sparse. Broad lithologic categories that are readily distinguished include: diabase/basalt, sandstone, shale, limestone, conglomerate, and hornfels. Using soil maps is not a substitute for field work, but is a valuable tool to aid in making geologic maps. Soil maps can also be used to produce derivative maps showing slope steepness and landslide distribution.
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11. the growth of soil series mapped in the usa. note the sudden increase in the number of soil series as soil taxonomy was adopted. Figure courtesy of dylan Beaudette, usda-nrcs, california soil resource lab
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Fig. 11. the growth of soil series mapped in the usa. note the sudden increase in the number of soil series as soil taxonomy was adopted. Figure courtesy of dylan Beaudette, usda-nrcs, california soil resource lab.
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