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Soil map

A soil map is a geographical representation that delineates the spatial distribution of soil types and key properties, such as texture, pH, organic matter content, and horizon depths, across a defined area.^[1] These maps result from systematic soil surveys, which involve examining, describing, classifying, and mapping soils to create practical delineations known as map units—areas dominated by one or more major soil components that share similar management needs.^[2]^[3] Unlike maps focused on a single property, soil maps integrate multiple attributes to support informed decision-making in land use.^[3] Soil mapping originated in the late 19th century, with the United States establishing a national program in 1899 under the U.S. Department of Agriculture (USDA), following initial surveys authorized in 1896.^[3] Early efforts, led by figures like Milton Whitney, produced the first nationwide soil map in 1909 and introduced the soil series concept in 1903 to standardize comparisons across regions.^[3] Internationally, the Food and Agriculture Organization (FAO) and UNESCO initiated the Soil Map of the World project in 1961, completing it in the 1980s to provide a standardized global soil inventory.^[4] Over time, advancements such as aerial photography in the 1930s, the adoption of Soil Taxonomy in 1975 for quantitative classification, digital techniques since the 1990s, and the GlobalSoilMap.net project since the 2000s for global digital soil mapping have transformed soil surveys into geospatial databases accessible via tools like the USDA's Web Soil Survey.^[2]^[3] Organizations like the FAO continue to promote standardized mapping to address global agricultural needs.^[1] The importance of soil maps lies in their role as foundational tools for sustainable land management, enabling assessments of soil productivity, crop suitability, and environmental risks.^[1] In agriculture, they guide precision farming, nutrient management, and irrigation by revealing variations in soil drainage, rooting depth, and fertility.^[2] For conservation and planning, maps inform erosion control, forestry practices, urban development, and recreation site design, such as parks or golf courses, while supporting policy decisions on biodiversity and water resource allocation.^[5]^[1] Modern digital soil mapping enhances accuracy and scalability, integrating remote sensing and modeling to predict soil behaviors under changing climates, exemplified by the 2025 release of a 90-meter resolution global soil properties map.^[3]^[6]

Definition and History

Definition

A soil map is a spatial representation of soil types, properties, or distributions across a geographic area, typically employing colors, symbols, or layered visualizations to delineate soil units based on key criteria such as texture, fertility, depth, drainage, and chemical composition.^[7] This cartographic tool integrates field observations and analytical data to portray the spatial variability of soils, enabling users to understand how soil characteristics influence landscape functions.^[5] Soil maps serve as foundational documents in pedology, the scientific study of soils, by providing a systematic depiction of soil resources rather than mere topographic or vegetative overlays.^[8] Essential components of a soil map include a legend that decodes symbols, colors, and patterns to represent specific soil attributes; the map scale, which determines the level of detail—for instance, a 1:50,000 scale is commonly used for regional assessments to balance resolution and coverage; clearly defined boundaries of soil polygons that outline homogeneous areas; and supplementary materials such as soil profiles describing vertical layers or data tables summarizing properties like pH and organic matter content.^[9]^[10] These elements ensure the map's interpretability and utility across scales from local plots to national extents.^[11] The core objectives of soil maps are to visualize inherent soil variability, facilitating informed decision-making in land use planning, natural resource management, and environmental research by predicting soil responses to various uses or stressors.^[12] For example, they guide the allocation of agricultural practices or conservation measures by highlighting areas of high fertility versus erosion-prone zones.^[5] This visualization supports sustainable development by linking soil data to broader ecological and economic contexts. Fundamental terminology in soil mapping encompasses the soil series, a conceptual grouping of soils with similar profiles and properties serving as the basic taxonomic unit in many systems; mapping units, which aggregate one or more soil series into practical delineations for cartographic representation, such as consociations or complexes; and the pedon, a three-dimensional soil body that represents the smallest volume of soil with inherent genetic homogeneity, typically 1–2 meters deep and laterally extensive enough to include horizon variations.^[13]^[11] These terms underpin the precision of soil maps, often drawing from established classification frameworks to standardize units across regions.^[14]

Historical Development

In the 19th century, systematic soil science emerged in Europe, particularly through the work of Russian scientist Vasily Dokuchaev in the 1880s. Dokuchaev established soil as an independent natural body, distinct from mere geological sediment, by integrating factors such as climate, organisms, relief, parent material, and time into a holistic model of soil formation.^[15] His studies of Russian chernozem soils and development of the first comprehensive soil map of European Russia marked a shift toward scientific pedology, influencing global approaches to soil classification.^[15] Key milestones in the early 20th century included the launch of the U.S. Soil Survey by the United States Department of Agriculture (USDA) in 1899, which initiated systematic field-based mapping to support agricultural planning.^[16] Under the leadership of Milton Whitney, the first chief of the Division of Soils, the survey introduced the soil series concept in 1903 to standardize soil descriptions and produced the first nationwide soil map in 1909.^[3] Influential figures advanced theoretical frameworks during this period; American pedologist Curtis Fletcher Marbut introduced the zonal soil concept in the 1920s, classifying soils into broad geographic zones based on climate and vegetation influences, as detailed in his 1927 scheme for soil classification.^[16] Building on this, Hans Jenny formalized the state factor equation in 1941 as a conceptual model for soil formation: S = f(cl, o, r, p, t), where S represents soil properties, cl is climate, o is organisms, r is relief (topography), p is parent material, and t is time; this equation describes soil as a function of these interacting state factors without implying causal processes or quantitative derivations.^[17] Standardized systems proliferated in the mid-20th century, with the USDA's Soil Taxonomy published in 1975 to provide a hierarchical classification for interpreting soil surveys based on diagnostic horizons and properties.^[18] Internationally, the Food and Agriculture Organization (FAO) of the United Nations initiated the World Soil Map project in 1961, releasing the first sheets in 1971 and the complete legend in 1974 at a 1:5,000,000 scale, fostering global soil correlation and resource assessment.^[19] The transition to digital methods began in the post-1980s era with the integration of geographic information systems (GIS), enabling data-driven mapping of soil properties beyond traditional zonal classifications.^[20]

Types of Soil Maps

Categorical Maps

Categorical soil maps divide landscapes into discrete polygons representing areas of similar soil classes, based on dominant properties such as texture, depth, and drainage, to facilitate broad-scale land use planning and resource management.^[11] These maps emphasize qualitative groupings rather than continuous variations, allowing users to identify general soil suitability for agriculture, forestry, or conservation without detailed quantitative measurements.^[21] The foundation of categorical soil maps lies in standardized classification systems that define soil classes for consistent mapping legends. In the United States, the USDA Soil Taxonomy organizes soils into 12 orders—such as Alfisols, characterized by clay-rich subsoils in humid regions, and Mollisols, known for their fertile, dark topsoils in grasslands—providing a hierarchical framework from orders to series that directly informs map unit delineations.^[22] Internationally, the FAO World Reference Base for Soil Resources (WRB) establishes 32 reference soil groups, including Acrisols with low-activity clays and Andosols formed from volcanic materials, serving as the basis for global soil map legends by grouping soils with shared diagnostic horizons and properties.^[23] These systems ensure that map legends are reproducible and comparable across regions, enabling the aggregation of finer soil data into broader categories for thematic applications. Design principles for categorical soil maps prioritize polygon-based representations, where boundaries delineate areas dominated by one or more soil components, often at scales like 1:250,000 for reconnaissance-level surveys that balance detail with practicality over large areas.^[11] Within these polygons, inclusions—minor soil areas or miscellaneous features too small to map separately at the chosen scale—are noted but not delineated as separate units, typically comprising less than 15-25% of the map unit to maintain focus on the dominant class; exclusions of highly dissimilar areas are similarly handled to avoid fragmentation.^[11] Prominent examples include the U.S. Web Soil Survey, which provides access to national categorical soil maps through the Soil Survey Geographic (SSURGO) database, displaying polygon-based units derived from USDA Soil Taxonomy for detailed county-level planning.^[24] On a global scale, the FAO/UNESCO Soil Map of the World, published in 1974 at 1:5,000,000, utilized an early version of the FAO legend to classify continental regions into broad soil associations, supporting international assessments of soil resources.^[4]

Thematic and Quantitative Maps

Thematic and quantitative soil maps depict specific soil attributes or continuous variables, such as pH levels, organic matter content, or erosion risk, rather than broad categorical classifications, enabling targeted analysis for precision agriculture and environmental assessment.^[25] These maps emphasize measurable properties to highlight spatial variability, supporting decisions on soil fertility management or contamination mitigation, and differ from categorical maps by representing data as gradients instead of discrete polygons.^[26] Their primary purpose is to provide quantifiable insights into soil health, facilitating the integration of multiple properties for comprehensive evaluations at local to regional scales.^[27] Representation methods for these maps include choropleth techniques, which use color gradients to visualize quantitative data like soil pH or nutrient concentrations across defined areas, allowing users to discern patterns of variation effectively.^[25] Isoline or isarithmic methods draw contour lines connecting points of equal value, such as soil depth or moisture levels, to illustrate continuous changes in the landscape.^[28] Multi-layer overlays in geographic information systems (GIS) combine these visualizations, stacking raster or vector layers to analyze interactions between properties like organic matter and cation exchange capacity (CEC).^[25] Common scales range from 1:10,000 for detailed farm-level planning to broader 1:50,000 for regional overviews, ensuring resolution matches the analytical needs.^[29] Data sources for thematic and quantitative soil maps primarily involve laboratory analyses of soil samples, integrating properties such as CEC—measured in centimoles of charge per kilogram (cmol/kg)—with field observations to create nutrient or contamination risk maps.^[30] For instance, soil nutrient maps derive from lab-tested samples of phosphorus or potassium levels, while contamination risk maps incorporate heavy metal concentrations from georeferenced sites.^[31] These sources are often combined with environmental covariates like terrain data to enhance accuracy, drawing from databases such as the USDA's Soil Survey Geographic Database (SSURGO).^[25] Specialized types include predictive soil maps generated via models like the SCORPAN framework, which forecast properties such as soil moisture indices based on factors including relief and climate, outputting continuous surfaces for dynamic assessments.^[25] These maps typically employ raster formats for grid-based representations of variability, though vector formats may delineate boundaries for integrated analyses, as seen in high-resolution predictions of volumetric soil moisture content.^[32] Such approaches enable proactive mapping of erosion-prone areas or moisture deficits without exhaustive field sampling.^[33]

Mapping Methods

Traditional Field-Based Methods

Traditional field-based methods for soil mapping emphasize direct, manual observation and sampling on the ground, forming the cornerstone of soil surveys through much of the 20th century and remaining dominant until the emergence of digital and predictive techniques in the 1990s.^[34] These approaches, often termed conventional or conventional soil survey, involve soil scientists physically traversing landscapes to identify soil variations, excavate profiles, and collect samples for classification and mapping.^[35] Ground-truthing through these methods ensures that maps reflect actual soil properties, such as texture, depth, and drainage, by relying on expert interpretation of landscape features and soil morphology.^[11] Key steps in traditional field-based mapping begin with traverse surveys, where surveyors walk systematic transects across the terrain—typically perpendicular to drainage patterns or along contours—to observe geomorphic features, vegetation, and erosion indicators that signal soil changes.^[35] These traverses guide the placement of observation points, with sampling intensity adjusted based on terrain complexity; for instance, in detailed surveys, points may be spaced every 100 meters along transects to capture variability. Following initial observations, soil pits are dug using shovels or backhoes to expose complete vertical profiles, allowing detailed description of horizons, including their thickness, color, texture determined by hand-feel methods, structure, and boundaries.^[35] Auger sampling complements this by extracting cylindrical cores at predetermined depths and intervals from the surface to the parent material or bedrock, facilitating rapid assessment in areas unsuitable for pits, such as steep slopes or rocky outcrops.^[11] Essential tools include hand augers for shallow sampling up to 2 meters, soil corers or push tubes for undisturbed cores, and spades for pit excavation, often paired with basic aids like Munsell color charts for visual assessment and pocket knives for texture evaluation.^[35] Protocols follow standardized guidelines, such as those in the USDA's Field Book for Describing and Sampling Soils (Version 4.0, 2024 edition), which provide codes and criteria for recording soil properties, including horizon nomenclature (e.g., A, Bt, C horizons) and physical attributes like consistence and moisture regime.^[36] Soils are classified on-site using keys aligned with Soil Taxonomy, focusing on diagnostic horizons and features.^[35] Map units are then delineated as polygons representing similar soils, with boundaries drawn based on observed transitions; a common criterion requires map unit purity of 80-85%, meaning no more than 15-20% dissimilar inclusions within the unit.^[35] Accuracy in these methods hinges on the soil scientist's expertise in interpreting field data and drawing boundaries, as automated tools are absent, leading to subjective elements in delineation.^[37] Validation typically involves cross-checking with additional samples or historical data, but error rates arise from intra-unit variability, sampling density limitations, and landscape heterogeneity not fully captured in traverses.^[38] Despite these challenges, such methods provide robust, verifiable data essential for establishing baseline soil maps.^[35]

Modern Digital and Remote Sensing Methods

Since the early 2000s, digital soil mapping has shifted toward data-driven approaches that leverage computational models and ancillary spatial data to produce soil maps more efficiently than traditional methods, with significant reductions in the need for extensive field surveys.^[39] This evolution has been driven by advances in computing power, the availability of high-resolution environmental covariates, and global initiatives like the GlobalSoilMap project launched in 2006, enabling scalable predictions of soil properties across landscapes.^[25] By integrating quantitative models, these techniques minimize subjective interpretations while providing maps with associated uncertainty estimates, supporting applications from local to global scales.^[25] Digital techniques in soil mapping primarily rely on geographic information systems (GIS) software, such as ArcGIS, to overlay and analyze spatial data layers for creating and updating soil maps.^[40] A core component is digital soil mapping (DSM), which employs machine learning algorithms like random forests to predict soil properties from environmental covariates, including elevation derived from digital elevation models (DEMs) and vegetation indices such as the normalized difference vegetation index (NDVI).^[41] These models train on legacy soil data points to infer continuous distributions of attributes like texture or organic carbon, often achieving prediction accuracies of 70-90% depending on the covariate set and region.^[25] Remote sensing plays a pivotal role by providing non-invasive data for soil characterization over large areas. Satellite imagery from platforms like Landsat and Sentinel-2 enables spectral analysis to infer soil color, moisture content, and organic matter through reflectance in visible and near-infrared bands.^[42] Hyperspectral sensors, such as those on satellites or airborne systems, detect mineral compositions by capturing hundreds of narrow spectral bands, allowing differentiation of soil types based on unique absorption features.^[43] Additionally, drone-based light detection and ranging (LiDAR) systems generate high-resolution topographic data, revealing micro-relief patterns that influence soil formation and distribution.^[44] These methods are integrated through predictive frameworks like the scorpan model, which conceptually represents soil properties (s) as a function (f) of climate (c), organisms (o), relief (r), parent material (p), age (a), and spatial position (n).^[45] In practice, this involves calibrating machine learning models with scorpan-derived covariates to extrapolate soil data spatially, ensuring predictions account for environmental correlations while incorporating spatial autocorrelation for realism.^[25] A prominent example is SoilGrids, launched by ISRIC in 2016, which provides global soil property maps at 250-meter resolution using machine learning on over 230,000 soil profiles and environmental covariates, offering predictions for attributes like pH and bulk density with quantified spatial uncertainty. An update, SoilGrids 2.0, was released in 2020 with enhanced predictions and additional coarser resolutions.^[46]^[47]

Applications

Agricultural Uses

Soil maps play a crucial role in precision agriculture by enabling site-specific management practices that optimize resource use and minimize environmental impact. Farmers utilize these maps to assess spatial variability in soil nutrients such as nitrogen (N), phosphorus (P), and potassium (K), allowing for variable-rate fertilizer application tailored to specific field zones. For instance, digital soil mapping integrated with global positioning systems (GPS) and yield monitors helps apply fertilizers only where deficiencies exist, reducing overuse and costs by 2-5% while maintaining crop health.^[48] This approach, supported by frameworks like the USDA's Soil Survey Geographic (SSURGO) database, enhances nutrient management efficiency and has been widely adopted in regions with intensive farming, such as the Midwest United States.^[49] In crop suitability assessments, soil maps identify optimal land for specific crops by correlating soil properties like texture, pH, and depth with agronomic requirements. The USDA's soil taxonomy, for example, highlights loamy soils as ideal for wheat production due to their balanced water retention and drainage, guiding farmers in selecting varieties and planting locations to maximize establishment and growth. Similarly, drainage maps derived from soil surveys inform irrigation planning, preventing waterlogging in poorly drained clays or supplementing arid sandy soils, as seen in California's Central Valley where such mappings support almond and grape cultivation. These applications ensure higher adaptation rates and reduce crop failure risks in diverse agroecological zones. Soil maps also contribute to yield optimization through erosion risk evaluation and targeted conservation practices. By delineating slopes, soil erodibility (K-factor), and runoff potential, maps guide the implementation of contour farming and terracing to mitigate soil loss, preserving topsoil fertility essential for sustained productivity. In India, the National Bureau of Soil Survey and Land Use Planning (NBSS&LUP) has zoned soils for rice cultivation, identifying alluvial and lateritic variants suitable for high-yield paddies in states like Punjab and West Bengal, leading to improved water and fertilizer distribution.^[50] Such zoning has supported national food security efforts by aligning cropping patterns with soil capabilities. Economically, the integration of soil maps into farming practices has demonstrated significant yield improvements, with studies reporting up to 10% increases in output from informed decision-making.^[51] For example, during the 2010s, the European Union's Common Agricultural Policy (CAP) incorporated soil mapping for subsidized precision farming, resulting in enhanced productivity across member states like France and Germany, where variable inputs based on soil data reduced operational costs and boosted net farm incomes.^[52] These gains underscore the value of soil maps in promoting sustainable intensification and economic resilience in agriculture.

Environmental and Land Management Uses

Soil maps play a crucial role in environmental conservation by identifying areas suitable for habitat restoration and assessing biodiversity. For instance, the Natural Resources Conservation Service (NRCS) utilizes soil surveys to map hydric soils—those formed under saturated conditions—which are essential for delineating wetlands and guiding restoration efforts. These maps help prioritize sites where hydrology can be restored cost-effectively, as hydric soils indicate former wetland areas even if altered by human activity.^[53]^[54] In biodiversity assessments, soil type mappings link edaphic characteristics to floral communities, serving as indicators for plant diversity across ecoregions and informing conservation strategies to protect soil-dependent ecosystems.^[55]^[56] In land use planning, soil maps inform zoning decisions to mitigate risks associated with development on unsuitable terrains. They highlight expansive clay soils, which swell and shrink with moisture changes, posing hazards to infrastructure; planners avoid such areas for building to prevent structural damage.^[57]^[58] Additionally, maps of soil permeability assess flood vulnerability by showing infiltration rates, enabling the identification of high-risk zones where low-permeability soils exacerbate runoff and inundation during heavy rains.^[59]^[60] For pollution management, thematic soil maps track contaminants such as heavy metals in industrial zones, revealing spatial distributions to target monitoring and intervention. In areas affected by mining or manufacturing, these maps quantify concentrations of elements like cadmium, lead, and zinc, aiding in risk assessment across large scales.^[61]^[62] Remediation planning relies on maps of soil pH and organic matter content, as these properties influence contaminant mobility and bioavailability; for example, acidic soils may enhance metal leaching, guiding lime amendments or organic additions to stabilize pollutants.^[63]^[64] Policy frameworks underscore the integration of soil maps in sustainable land management. The European Union's 2006 Thematic Strategy for Soil Protection proposed standardized mapping to address degradation threats, promoting cross-border data for erosion control and organic carbon preservation, though full legislative adoption faced delays.^[65]^[66] Globally, carbon stock mappings, such as the FAO's Global Soil Organic Carbon map, support climate adaptation by estimating sequestration potential and identifying restoration sites to enhance soil resilience against warming.^[67]^[68]

Challenges and Advances

Current Limitations

Despite significant advancements, soil mapping continues to face substantial accuracy gaps, particularly in delineating spatial boundaries and predicting properties in complex landscapes. Legacy soil maps often exhibit error rates ranging from 58% to 87% when compared to field validations for topsoil texture, with allocation errors in boundary placement contributing approximately 45% to overall disagreement. ^[38] These uncertainties are exacerbated in heterogeneous terrains such as mountainous regions, where topographic variability, steep gradients, and microclimatic differences lead to high spatial heterogeneity in soil properties, complicating predictive models and reducing mapping precision. ^[69] Global data coverage remains incomplete, especially in developing regions, hindering comprehensive soil management. For instance, only about 49% of African countries have conducted digital soil mapping studies, with most limited to local scales and relying on legacy datasets over 40 years old, resulting in sparse and clustered sampling that fails to capture detailed continental variability. ^[70] Outdated surveys in these areas, such as those in parts of sub-Saharan Africa and Southeast Asia, often stem from mid-20th-century efforts with low resolution and positional inaccuracies, leaving vast regions unmapped or inadequately updated. ^[70] Accessibility poses further barriers due to the resource-intensive nature of soil mapping. Traditional field-based surveys can cost around 8-10 USD per square kilometer at medium scales (e.g., 1:200,000), but expenses escalate significantly for detailed work in remote or challenging areas, limiting adoption by under-resourced institutions. ^[71] Additionally, many digital soil mapping tools and datasets are proprietary, restricting open access and collaboration, particularly in low-income settings where free alternatives are essential for equitable data sharing. ^[72] Environmental factors, including climate change, introduce dynamic challenges that outpace current mapping capabilities. Anthropogenic climate change has driven desertification across over 5 million square kilometers of drylands since the 1980s, rapidly altering soil properties such as organic matter and fertility through reduced water availability and vegetation loss in affected areas, while remapping cycles—often spanning decades—fail to keep up with these shifts. ^[73]

Emerging Technologies and Future Directions

Advancements in artificial intelligence and machine learning are revolutionizing digital soil mapping (DSM) by enabling hyper-local predictions with unprecedented accuracy and resolution. Neural networks, integrated with platforms like Google Earth Engine, facilitate the processing of vast multispectral and environmental datasets to generate soil property maps at resolutions as fine as 30 meters globally. ^[74] For instance, convolutional neural networks have been employed in multi-scale frameworks to predict root-zone soil moisture and other attributes by fusing active and passive remote sensing data, achieving improved spatial detail for precision agriculture. ^[75] These techniques extend beyond traditional random forest or decision tree models, offering enhanced generalization for underrepresented regions through transfer learning and ensemble methods. Sensor technologies are evolving to support real-time soil data collection, complementing satellite-based mapping with ground-level precision. Portable spectrometers, leveraging hyperspectral imaging, allow for on-site analysis of soil composition, including moisture and organic content, by inverting spectral signatures against reference libraries. Meanwhile, Internet of Things (IoT) soil probes enable continuous monitoring of parameters like pH and nutrient levels, transmitting data via wireless networks for integration into dynamic mapping systems. Satellite constellations under the Copernicus program provide annual updates on soil moisture through gridded products derived from radar and microwave observations, covering surface layers up to 1 meter depth with near-real-time availability. ^[76] These advancements facilitate seamless fusion of in-situ and remote data, enhancing the temporal resolution of soil maps. Global initiatives are driving collaborative efforts to standardize and democratize soil mapping, particularly for carbon sequestration. The 4 per 1000 Initiative, launched in 2015 and active through the 2020s, promotes soil carbon mapping to support agricultural practices that increase organic matter by 0.4% annually, aiding climate mitigation and food security. ^[77] Complementing this, open-source platforms like OpenLandMap deliver free, high-resolution global soil datasets at 30-meter scales, aggregating legacy profiles and predictive models for properties such as organic carbon and bulk density. ^[74] These resources empower researchers and policymakers in under-resourced areas to access verifiable soil information without proprietary barriers. Looking ahead, integrating soil mapping with climate models promises predictive capabilities for long-term land health. By coupling DSM outputs with general circulation models, forecasts of soil degradation—such as erosion rates increasing 13–22.5% in the EU and UK by 2050 due to intensified rainfall—enable proactive interventions like targeted restoration. ^[78] Similarly, projections of soil organic matter under nature-inclusive scenarios highlight pathways to maintain carbon stocks amid land-use shifts. However, these developments raise ethical concerns, particularly in crowdsourced mapping, where data privacy must be safeguarded through anonymization and consent protocols to protect landowner rights and prevent misuse of geolocated soil profiles. Frameworks emphasizing transparent data stewardship are essential to ensure equitable benefits from participatory soil monitoring.

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Jan 11, 2023 · Total disagreement among the map and field data ranges from 58% to 87%. When considering only those maps produced through the linking of ...
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Digital soil mapping: A brief history and some lessons - ScienceDirect
Feb 15, 2016 · In this paper, we define what constitutes digital soil mapping, sketch a brief history of it, and discuss some lessons.
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Digital Soil Mapping (DSM) | ArcGIS Hub Home
Digital Soil Mapping (DSM). Digital Soil Mapping is a technique that combines expert opinion with statistical modeling, and geospatial layers with field ...Missing: machine learning
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Digital mapping of soil texture classes for efficient land management ...
Jun 23, 2022 · The random forest algorithm is the most popular machine learning algorithm for regression and classification of soil texture. The random forest ...
[43]
Prediction of soil texture using remote sensing data. A systematic ...
Reviewed studies reported the prediction of soil texture using variable satellite images including the Landsat 5, 7, and 8, Sentinel 1 and 2, Moderate ...Missing: drones | Show results with:drones
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A review: soil properties mapping estimation using remote and ...
Sep 13, 2024 · This review paper aims to review the status of current mapping methods and provide deeper and more detailed insight into techniques in contemporary systematic ...
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[PDF] UAV hyperspectral and lidar data and their fusion for arid and semi ...
Abstract. Unmanned aerial vehicles (UAVs) provide a new research tool to obtain high spatial and temporal resolution imagery at a reduced cost.
[46]
On digital soil mapping - ScienceDirect
The generic framework, which we call the scorpan-SSPFe (soil spatial prediction function with spatially autocorrelated errors) method, is particularly relevant ...
[47]
Global gridded soil information based on machine learning
This paper describes the technical development and accuracy assessment of the most recent and improved version of the SoilGrids system at 250m resolution ...
[48]
Hydric Soils - Natural Resources Conservation Service
NRCS delivers science-based soil information to help farmers ... Choose a state and soil survey area to get a hydric soils report from Soil Data Access.
[49]
[PDF] Hydric Soils of Problematic Conditions and Altered Materials
It has been demonstrated that restoring hydrology to former wetlands that have hydric soils is a much more cost-effective and predictably successful venture ...<|separator|>
[50]
Soil indicators of plant diversity for global ecoregions
Environmental indicators have been developed widely to promote biodiversity conservation, ecological restoration, and nature resource management from local ...
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Linking soil biodiversity and vegetation: Implications for a changing ...
Mar 1, 2011 · Soil biota are intimately tied to plant communities through herbivory and symbiosis and indirectly by the decomposition of dead organic plant material.Soil Animal Diversity · Distribution Of Soil Animals · Soil Animals And Nutrient...
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Expansive Soil and Rock - Colorado Geological Survey
Expansive or swelling soils are one of the most prevalent causes of damage to buildings and construction in the US.Missing: zoning | Show results with:zoning
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Expansive soils (shrink swell clays) - NC DEQ
Where do they occur? Expansive soils can occur in almost any location in the Mountains, Piedmont, and Coastal Plain of North Carolina.Missing: zoning | Show results with:zoning
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Soil permeability classification. | Download Scientific Diagram
Flood risk mapping has witnessed the extensive use of multicriteria decision-making techniques such as weighted sum (Enomah et al., 2023) and analytical ...
[55]
GIS-based mapping of flood hazard areas and soil erosion using ...
Apr 3, 2025 · This study aimed to create a GIS-based flood hazard map and estimate annual soil loss using the Universal Soil Loss Equation (USLE)
[56]
Toxic metals abound in soils worldwide, new global map reveals
Apr 17, 2025 · Researchers have created the first global map of toxic metals in soils, showing that vast swaths of land are contaminated from a combination of factors.
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Heavy metals concentration in soils across the conterminous USA
Apr 1, 2024 · This study aimed to predict and map the distribution of Cd, Cu, Ni, Pb, and Zn across the conterminous USA using point observations, environmental variables,Heavy Metals Concentration... · 2. Materials And Methods · 4. Discussion
[58]
Maps of heavy metals in the soils of the European Union and ...
Sep 15, 2016 · Detailed and up-to-date maps of heavy metals (As, Cd, Cr, Cu, Hg, Pb, Zn, Sb, Co and Ni) in the topsoil of the European Union were produced.
[59]
Mapping of heavy metal pollution density and source distribution of ...
Dec 2, 2024 · Accurate mapping of the spatial distribution of heavy metals in soil is the primary stage in risk assessment and remediation of contaminated ...
[60]
https://geoscienceletters.springeropen.com/articles/10.1186/s40562-025-00382-w
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EU Soils Thematic Strategy
This soil thematic strategy seeks to: establish common principles for the protection and sustainable use of soils; prevent threats to soils, and mitigate the ...
[62]
Global Soil Organic Carbon map (GSOCmap)
The GSOCmap provides users with very useful information to monitor the soil condition, identify degraded areas, set restoration targets, explore SOC ...
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FAO Maps Carbon Stocks in Soil | UNFCCC
Dec 7, 2017 · The map shows that globally, the first 30 cm of soil contains around 680 billion tonnes of carbon - almost double the amount present in our atmosphere.
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A Methodological Study on Improving the Accuracy of Soil Organic ...
The study area is primarily mountainous, with large undulations and complex terrain, resulting in differences in soil water and heat conditions and vegetation ...
[65]
Applications and challenges of digital soil mapping in Africa
This review aims to investigate the current state of DSM in Africa, identify challenges specific to implementing DSM in Africa and the ways it has been solved ...
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5 Statistical theory for predictive soil mapping
... map soil at 1:200,000 scale globally would cost about 8 USD per square-kilometer using conventional soil mapping methods. A scale of 1:200,000 corresponds ...
[67]
Free, open, quantitative and adaptable digital soil map data and ...
Jun 27, 2020 · The DSM incorporates queries and spatial analyses tools to generate thematic maps of basic soil properties within the context of Nigeria such as ...
[68]
Anthropogenic climate change has driven over 5 million km2 of ...
Jul 31, 2020 · Anthropogenic climate change has degraded 12.6% (5.43 million km 2 ) of drylands, contributing to desertification and affecting 213 million people.