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What is primarily examined in the first order of soil survey?
What is primarily examined in the first order of soil survey?
What is NOT a layer in the hierarchy of soil classification as described?
What is NOT a layer in the hierarchy of soil classification as described?
Which of the following is considered in land suitability classes?
Which of the following is considered in land suitability classes?
Which of these properties is NOT part of soil taxonomy based on USDA soil surveys?
Which of these properties is NOT part of soil taxonomy based on USDA soil surveys?
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What is the primary purpose of organizing knowledge about soils?
What is the primary purpose of organizing knowledge about soils?
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Which factor is NOT directly associated with soil formation processes?
Which factor is NOT directly associated with soil formation processes?
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What is the primary component of soil solids?
What is the primary component of soil solids?
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During which stage of soil formation does chemical weathering occur?
During which stage of soil formation does chemical weathering occur?
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Which method is NOT an approach in soil study?
Which method is NOT an approach in soil study?
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What is a pedon in soil science?
What is a pedon in soil science?
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Which soil texture is characterized by the highest bulk density?
Which soil texture is characterized by the highest bulk density?
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Which process is primarily driven by rainfall in soil formation?
Which process is primarily driven by rainfall in soil formation?
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What is the primary reason tropical soils weather faster than other soils?
What is the primary reason tropical soils weather faster than other soils?
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What component contributes most to the soil organic matter (SOM) accumulation in grasslands compared to forests?
What component contributes most to the soil organic matter (SOM) accumulation in grasslands compared to forests?
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Which of the following is not a primary reason for the decline of organic matter (OM) due to cultivation?
Which of the following is not a primary reason for the decline of organic matter (OM) due to cultivation?
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What is the primary focus of soil classification?
What is the primary focus of soil classification?
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Which hierarchy level of soil classification is responsible for addressing moisture and temperature regimes?
Which hierarchy level of soil classification is responsible for addressing moisture and temperature regimes?
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What level of soil survey is best suited for regional planning?
What level of soil survey is best suited for regional planning?
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Which consideration is excluded from land suitability classes?
Which consideration is excluded from land suitability classes?
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What is identified as the basic unit within the soil classification system?
What is identified as the basic unit within the soil classification system?
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Which property is significant in soil taxonomy?
Which property is significant in soil taxonomy?
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Which order of soil survey is primarily applied for urban planning?
Which order of soil survey is primarily applied for urban planning?
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What is the main factor influencing the productivity of a soil type?
What is the main factor influencing the productivity of a soil type?
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Which organisms are essential for reducing sulfate to sulfide?
Which organisms are essential for reducing sulfate to sulfide?
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What is the typical range of cellulose composition in soil organic matter?
What is the typical range of cellulose composition in soil organic matter?
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Which soil component significantly enhances oxidation and microbial activity during cultivation?
Which soil component significantly enhances oxidation and microbial activity during cultivation?
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Which type of mycorrhizae is known for penetrating plant root cells?
Which type of mycorrhizae is known for penetrating plant root cells?
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Which organic component typically has the highest percentage in soil?
Which organic component typically has the highest percentage in soil?
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What is the typical carbon-to-nitrogen (C/N) ratio range for finished compost?
What is the typical carbon-to-nitrogen (C/N) ratio range for finished compost?
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Which process is not directly associated with microbial metabolism of sulfur compounds?
Which process is not directly associated with microbial metabolism of sulfur compounds?
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What amendment is effective in mitigating high soil salinity?
What amendment is effective in mitigating high soil salinity?
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What is the effect of flooding on ferric phosphate in soil?
What is the effect of flooding on ferric phosphate in soil?
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What does the hierarchy of soil classification conclude with at the most granular level?
What does the hierarchy of soil classification conclude with at the most granular level?
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Which of the following factors is NOT listed as a concern for determining land suitability?
Which of the following factors is NOT listed as a concern for determining land suitability?
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Which chemical property of soil is indicated by the given equivalence of 1 cmol to 0.40 g for calcium?
Which chemical property of soil is indicated by the given equivalence of 1 cmol to 0.40 g for calcium?
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What does the term 'great group' refer to in soil classification?
What does the term 'great group' refer to in soil classification?
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Which soil process is primarily associated with the microbial decomposition of organic materials like cellulose and hemicellulose?
Which soil process is primarily associated with the microbial decomposition of organic materials like cellulose and hemicellulose?
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Which factor most substantially affects the moisture content and thus the organic matter accumulation in soils?
Which factor most substantially affects the moisture content and thus the organic matter accumulation in soils?
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What is the main focus of the first order of soil survey?
What is the main focus of the first order of soil survey?
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Which of the following is a part of the soil classification hierarchy?
Which of the following is a part of the soil classification hierarchy?
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Which aspect is considered when assessing land suitability?
Which aspect is considered when assessing land suitability?
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Which property is commonly associated with soil taxonomy under USDA standards?
Which property is commonly associated with soil taxonomy under USDA standards?
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What is an essential purpose of organizing soil knowledge?
What is an essential purpose of organizing soil knowledge?
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Which of the following does not directly relate to soil formation processes?
Which of the following does not directly relate to soil formation processes?
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What is the predominant component of the solid fraction of soil?
What is the predominant component of the solid fraction of soil?
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During which stage does chemical weathering predominantly take place?
During which stage does chemical weathering predominantly take place?
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What type of mycorrhizae penetrate root cells to aid in nutrient absorption?
What type of mycorrhizae penetrate root cells to aid in nutrient absorption?
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What does the cmol value of calcium primarily indicate in soil?
What does the cmol value of calcium primarily indicate in soil?
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How does flooding generally affect ferric phosphate levels in soil?
How does flooding generally affect ferric phosphate levels in soil?
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What primary role do actinomycetes play in soil ecology?
What primary role do actinomycetes play in soil ecology?
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Which fungus is notably responsible for cellulose decomposition?
Which fungus is notably responsible for cellulose decomposition?
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What is the main purpose of composting in soil management?
What is the main purpose of composting in soil management?
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Which order of soil survey is specifically designed for experimental purposes?
Which order of soil survey is specifically designed for experimental purposes?
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What is the primary criterion used to differentiate soil suborders?
What is the primary criterion used to differentiate soil suborders?
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Study Notes
Soil Survey Order
- The first order of soil survey is the most detailed and intensive, typically used for experiments and building sites.
Soil Classification Hierarchy
- The hierarchy includes order, great group, subgroup, family, and series, but not 'type'.
Land Suitability Classes
- Limitations to tillage and plant rooting play a crucial role in assessing land suitability classes.
Soil Taxonomy Based on USDA Soil Surveys
- Soil taxonomy is based on observable properties, properties influencing soil genesis, and general soil properties, not specifically organic carbon content.
Organizing Soil Knowledge
- Understanding the relationships among different soil types is the primary purpose of organizing soil knowledge.
Soil Formation Processes
- Nutrient absorption by plants happens in established soil, but it doesn't directly contribute to its formation.
Soil Solids Composition
- Minerals constitute the majority (45%) of the solid components of soil, while organic matter makes up only 5%.
Chemical Weathering in Soil Formation
- Chemical weathering plays a vital role in soil horizon formation as minerals break down and alter the soil composition.
Soil Study Approaches
- Acid-base chemistry is a specific aspect of soil chemistry, not a broader approach like microbiology, land use, and survey & classification.
Pedon in Soil Science
- A pedon is the smallest unit of soil that can be characterized, measuring between 1 to 10 square meters.
Soil Texture and Bulk Density
- Sand typically has the highest bulk density (1.20 to 1.80 g/cm3) compared to clay and silt.
Rainfall's Impact on Soil Formation
- Rainfall significantly contributes to chemical weathering by facilitating hydrolysis, hydration, and other reactions that alter soil composition.
Tropical Soil Weathering
- Higher temperatures in tropical climates accelerate chemical reactions, leading to faster weathering of soils.
Grasslands vs. Forests: Organic Matter Accumulation
- Faster vegetative matter turnover due to shorter grass life cycles leads to more organic matter accumulation in grasslands compared to forests.
Organic Matter Decline due to Cultivation
- Enhanced oxidation is a primary reason for the decline of organic matter (OM) due to cultivation.
Soil Survey
- First order soil survey is the most detailed and intensive survey, used mainly for experimental purposes and building sites.
- Second order is utilized for detailed urban planning.
- Third order covers an area of 16-252 ha, focusing on general land management purposes.
- Fourth order covers smaller areas, ranging from 0.6-4 ha, suitable for specific land uses like livestock facilities.
- Fifth order is the most exploratory level of the soil survey and covers the largest area, making it appropriate for regional planning.
Soil Classification Hierarchy
- Order is the broadest level of classification, based on basic diagnostic features and differentiating between major soil types.
- Suborder focuses on moisture and temperature regimes, indicating the climate's impact on soil development.
- Great group categorizes soils based on the arrangement and properties of their horizons, highlighting key physical and chemical characteristics.
- Subgroup identifies soils with specific diagnostic features and variations within the great group.
- Family further classifies soils based on texture, mineralogy, and other physical properties for agricultural use and management.
- Series is the most granular level, identifying soils with similar characteristics, location, and potential uses, often including a name like "Waverly silt loam".
Soil Properties and Formation
- Soil solids are primarily composed of minerals, constituting about 45% of soil composition, while organic matter makes up only 5%.
- Chemical weathering plays a crucial role in soil formation, breaking down minerals and releasing nutrients.
- Soil horizon formation is a key process in soil development, resulting in distinct layers with different properties, such as the topsoil, subsoil, and bedrock.
- Climate is a major influence on soil formation processes, impacting weathering rates and organic matter decomposition.
- Living organisms contribute significantly to soil formation through their activities like decomposition, nutrient cycling, and soil structure modification.
Soil Organic Matter
- Cellulose comprises 15-60% of soil organic matter, while hemicellulose and lignin compose smaller proportions.
- Organic matter influences soil structure, water-holding capacity, nutrient availability, and microbial activity, contributing to overall soil health.
Microbial Activity in Soils
- Actinomycetes are microorganisms vital for decomposing complex organic compounds in soils, contributing to nutrient cycling and soil health.
- Mycorrhizal fungi form symbiotic relationships with plant roots, aiding in nutrient uptake, especially phosphorus, enhancing plant growth.
- Endomycorrhizae penetrate plant root cells directly, assisting in nutrient absorption, and promoting plant growth.
- Desulfovibrio and Desulfotomaculum are microorganisms involved in the reduction of sulfate to sulfide, influencing sulfur availability in soil.
Soil Management Practices
- Composting involves decomposing organic waste, leading to the creation of humus-like material, enriching soil fertility and improving soil structure.
- High salinity in soils can be mitigated through proper irrigation, regular drainage, and the application of amendments like organic fertilizers, helping to leach excess salts.
- Flooding typically reduces ferric phosphate availability in soil, impacting its nutrient dynamics.
- Regular drainage is crucial in reducing soil salinity, contributing to better soil health and plant performance.
Key Concepts
- Soil taxonomy is a system of classifying soils based on observable properties, properties affecting genesis, and general soil properties, helping to organize knowledge about soils and understand their relationships.
- Land suitability classes evaluate land for potential uses, considering limitations to tillage, plant rooting, erosion, and wetness, aiding in sustainable land management decisions.
- Exchange capacity signifies the soil's ability to retain nutrients, heavily influenced by the presence of minerals like calcium and its associated cmol value.
- Soil classification helps predict soil behavior, estimate productivity, and categorize soil types, providing valuable information for land management, agriculture, and urban planning.
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Description
Test your knowledge on soil survey orders, classification hierarchies, and land suitability classes. This quiz covers soil taxonomy based on USDA soil surveys and the processes involved in soil formation. Perfect for students and professionals interested in soil science.
