SHS G11 Soil Resources PDF

Soil Resources Earth Science | SHS | Grade 11  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. https://www.sciencefacts.net/soil-horizons.html...

Soil Resources Earth Science | SHS | Grade 11  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. https://www.sciencefacts.net/soil-horizons.html  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 1. O Horizon – Organic Layer - uppermost layer of the soil rich in organic matter, such as the remains of plants and dead animals https://www.sciencefacts.net/soil-horizons.html  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 2. A Horizon – Topsoil - dark brown color as it contains the maximum organic matter of the soil - humus makes the topsoil highly porous https://www.sciencefacts.net/soil-horizons.html  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 3. E Horizon – Eluviation layer - consists of nutrients leached from O and A horizons - Leaching of clay, minerals, and organic matter leaves this layer with a high concentration of sand, slit particles, quartz, and other resistant material https://www.sciencefacts.net/soil-horizons.html  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 4. B Horizon – Subsoil - Mostly found below the topsoil - has less organic content but is rich in minerals that are leached down from the topsoil - holds enough water due to its https://www.sciencefacts.net/soil-horizons.html clayey nature  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 5. C Horizon – Parent rock - regolith or saprolite, lies below the subsoil - upper layers developed from this layer - devoid of any organic matter and https://www.sciencefacts.net/soil-horizons.html is made of broken-up bedrocks  SOIL FORMATION Soil forms through weathering of rocks and organic matter accumulation, influenced by climate, organisms, topography, parent material, and time. Layers: 6. R Horizon – Bedrock - Found beneath all the layers - consists of un-weathered igneous, sedimentary, and metamorphic rocks - highly compact - Granite, basalt, quartzite, sandstone, and https://www.sciencefacts.net/soil-horizons.html limestone  Soil Composition Minerals Water and Air Organic Matter Composed of sand, silt, Essential for soil health, Decomposed plant and and clay, which affecting nutrient animal residues enrich soil influence soil texture availability and microbial fertility and structure. and structure. activity.  Activities That Affects Soil Quality and Quantity HUMAN CAUSES Soil erosion occurs naturally by wind or harsh climatic conditions, but human activities include overgrazing, overcropping and deforestation. Overgrazing occurs when farmers stock too many animals such as sheep, cattle or goats on their land. Activities That Affects Soil Quality and Quantity FARMING Activities That Affects Soil Quality and Quantity FARMING Negative Effects of Farming: * Tillage – all tillage operations, including aeration and sward lifting cause direct damage to soil microfauna and potentially expose them to new predators Activities That Affects Soil Quality and Quantity FARMING Negative Effects of Farming: * Pesticides – are a diverse group of chemicals used to control insects and other organisms harmful to cultivated plants and animals. Activities That Affects Soil Quality and Quantity FARMING Negative Effects of Farming: * Veterinary Medicines – direct application of anti- microbials and nematicide usually used in veterinary medicines to soil has been shown negative impact on soil organisms. Activities That Affects Soil Quality and Quantity FARMING Negative Effects of Farming: Veterinary Medicines – evidence of reduced numbers of activity of dung beetles where veterinary drugs are used regularly, retarded decomposition rates of dung are likely to have impacts on other soil organisms and reduce the positive impact that dung can have in maintain the soil Study: Sommer, C., & Bibby, B. M. (2002, April). The influence of veterinary medicines on the decomposition of... Research Gate. DOI:10.1016/S1164- 5563(02)01138-X Activities That Affects Soil Quality and Quantity FARMING Positive Effects of Farming: Herbicides – have a range of target effects on plant cover which are likely to result in a range of indirect effects on soil organisms. earthworms – benefit more from weedy conditions Activities That Affects Soil Quality and Quantity FARMING Positive Effects of Farming: Lime and minerals – provide stable optimum growing conditions on plants, meet plant nutrient demand, and maintain balanced nutrient budget Balanced fertilization has a positive impact on soil health. Activities That Affects Soil Quality and Quantity FARMING Positive Effects of Farming: Plant growth – direct link to soil organisms; provides energy through root growth and exudation in the soil during growth and the amount and quality of litter or residues returned to the soil Activities That Affects Soil Quality and Quantity FARMING Positive Effects of Farming: Organic manures and other organic fertilizers – provides inputs of organic matter, providing source of energy/food for many soil organisms – leading to the increase in their population Activities That Affects Soil Quality and Quantity FARMING Positive Effects of Farming: Drainage and irrigation – effect is indirect; regulates the seasonal effect of rainfall patterns, which tend to stabilize the soil moisture regime away from extremes Activities That Affects Soil Quality and Quantity CONSTRUCTION OF STRUCTURES Activities That Affects Soil Quality and Quantity CONSTRUCTION OF STRUCTURES Soil quality has been overlooked as crucial component in urban areas, as well as agricultural environment. Causes – rapid degradation of soil soil erosion Sedimentation Construction activities, such as grading and filling, reduce soil quality on construction sites. Activities That Affects Soil Quality and Quantity WASTE DISPOSAL Activities That Affects Soil Quality and Quantity WASTE DISPOSAL In 2023, the projected waste generation in the Philippines reached 60,640 tons per day, indicating an increase from the previous year. Across regions, CALABARZON accounted for the highest volume of projected waste generation in that year, followed by the National Capital Region. https://www.statista.com/statistics/1347560/philippines-projected-daily-waste- generation/#:~:text=In%202023%2C%20the%20projected%20waste,by%20the%20Nationa l%20Capital%20Region. Activities That Affects Soil Quality and Quantity WASTE DISPOSAL Challenges of waste management and recycling industry in the PH: High levels of plastic pollution Lack of proper waste disposal infrastructure Inadequate waste collection services Informal waste sector Lack public awareness; human behavior https://plasticbank.com/blog/top-5-waste-management- challenges-in-the-philippines-and-how-to-solve-them/  Threats to Soil Health Soil Erosion Acidification Organic Carbon Loss of Soil Loss Biodiversity Nutrient Imbalance Soil Sealing Salinization Compaction Contamination Water Loging Threats to Soil Health Soil Erosion - the accelerated removal of topsoil from the land surface through water, wind or tillage (https://www.unccd.int/sites/default/files/2018- 06/17.%20Threats%2Bto%2BSoils__Pierzynski_Brajendra.pdf) - contributes to the decline of soil health by removing essential nutrients and minerals from the soil, making it more difficult for plants to take up the nutrients they need to grow (https://www.holganix.com/blog/top-10-threats-to-soil-health#soil-erosion) Threats to Soil Health Soil Organic Carbon (SOC) Loss - refers to the reduction in the amount of organic carbon in the soil (https://www.holganix.com/blog/top-10-threats-to- soil-health#soil-erosion) - Reasons: Threats to Soil Health Soil Organic Carbon (SOC) Loss SOC loss can occur in variety of reasons: Agricultural practices - tillage, monoculture cropping systems, and the use of synthetic fertilizers can reduce soil organic carbon levels by altering the soil food web and reducing the input of organic matter. Land use change - converting natural ecosystems, such as forests and wetlands, to agricultural or urban use can result in a significant loss of soil organic carbon. Climate change - changes in temperature and precipitation patterns, as well as increased frequency of extreme weather events, can impact the rate of organic matter decomposition and soil organic carbon levels. Threats to Soil Health Soil Organic Carbon (SOC) Loss Negative impacts in soil health: Reduced soil fertility - soil organic carbon is an essential component of soil fertility, providing essential nutrients for plant growth. Decreased water-holding capacity - soil organic carbon contributes to soil water-holding capacity, which is essential for plant growth. Increased greenhouse gas emissions - soil organic carbon is a large pool of carbon, and soil organic carbon loss can result in the release of carbon dioxide (CO2) and other greenhouse gases into the atmosphere, contributing to climate change. Threats to Soil Health Soil Nutrient Imbalance - implies nutrient inputs and losses from the soil system are equal while an imbalance is the net gain or loss of plant nutrients from the zone of soil that is accessible by plant roots (https://www.unccd.int/sites/default/files/2018- 06/17.%20Threats%2Bto%2BSoils__Pierzynski_Brajendra.pdf) Threats to Soil Health Soil Nutrient Imbalance Imbalance leads to various issues: 1. Reduced plant growth - an imbalance of essential nutrients can limit plant growth, as the plant is unable to take up the necessary nutrients for growth. 2. Soil acidification - an imbalance of essential nutrients can also result in soil acidification, which can reduce the availability of essential plant nutrients and reduce soil fertility. Threats to Soil Health Soil Nutrient Imbalance Imbalance leads to various issues: 3. Changes in soil biota - an imbalance of essential nutrients can also affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health. 4. Altered soil chemistry - an imbalance of essential nutrients can also alter soil chemistry, reducing the availability of essential plant nutrients and impacting soil health. Threats to Soil Health Soil Nutrient Imbalance Causes: over-fertilization imbalanced use of fertilizers soil degradation, and loss of soil organic matter Threats to Soil Health Soil Salinization and Sodification - implies the process by which soil becomes increasingly salty, leading to a decline in soil fertility and productivity - occurs when salts in the soil accumulate to levels that are toxic to plants, altering the soil's physical, chemical, and biological properties (https://www.unccd.int/sites/default/files/2018- 06/17.%20Threats%2Bto%2BSoils__Pierzynski_Brajendra.pdf) - Sodification - an accumulation of sodium on clay exchange sites leading to structural decline (https://www.soilscienceaustralia.org.au/about/save-our-soils/sos-salinisation- and-sodification/ Threats to Soil Health Soil Contamination - Introduction of harmful substances into the soil that can harm plants, animals, and humans - Occurs due to various sources ▪ Agricultural practices - the use of pesticides, fertilizers, and other chemicals in agriculture can lead to soil contamination. ▪ Industrial activities - industries such as mining, manufacturing, and waste disposal can release toxic chemicals into the soil. ▪ Natural sources - soil can also become contaminated through natural processes, such as volcanic eruptions or leaching of minerals from rocks. Threats to Soil Health Soil Contamination - Negative Impacts: ▪ Reduced plant growth - contaminated soil can contain harmful chemicals that can harm or kill plants, reducing overall productivity. ▪ Toxicity to animals - contaminated soil can be toxic to animals, including wildlife, domesticated animals, and even humans. Threats to Soil Health Soil Contamination - Negative Impacts: ▪ Health risks to humans - contaminated soil can pose a risk to human health, particularly if the contaminants are ingested or inhaled. ▪ Decreased biodiversity - soil contamination can reduce the diversity of soil organisms and disrupt the soil food web, reducing the overall health of the soil ecosystem. Threats to Soil Health Soil Acidification - the process by which soil pH decreases, becoming more acidic - Soil pH (soil’s alkalinity or acidity); pH range 0-14 - occur naturally over time, but it can also be accelerated by human activities, such as the use of acidifying fertilizers, land use change, and soil degradation Threats to Soil Health Soil Acidification - Effects on soil: ▪ Reduced availability of essential plant nutrients - soil acidification can reduce the availability of essential plant nutrients, such as calcium, magnesium, and phosphorus, which are essential for healthy plant growth. ▪ Altered soil biota - soil acidification can also affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health. Threats to Soil Health Soil Acidification - Effects on soil: - Reduced plant growth - soil acidification can limit plant growth by reducing the availability of essential plant nutrients and altering soil biota. - Increased metal toxicity - soil acidification can also increase the availability of toxic metals, such as aluminum and manganese, which can be toxic to plants and other soil biotas. Threats to Soil Health Loss of Soil Biodiversity - closely tied to the diversity of soil biota, such as microorganisms, insects, and plants - Ways in which loss of soil biodiversity can affect soil health: ▪ Disrupting the soil food web - the loss of biodiversity can disrupt the delicate balance of the soil food web, reducing the ability of soil organisms to carry out important processes, such as nutrient cycling and decomposition. Threats to Soil Health Loss of Soil Biodiversity - Ways in which loss of soil biodiversity can affect soil health: ▪ Decreased nutrient cycling - soil biota plays a critical role in nutrient cycling, breaking down organic matter and making essential nutrients available to plants. Loss of biodiversity can reduce the efficiency of nutrient cycling, reducing soil fertility and overall health. Threats to Soil Health Loss of Soil Biodiversity - Ways in which loss of soil biodiversity can affect soil health: - Increased vulnerability to soil degradation - soil ecosystems with high levels of biodiversity are typically more resilient to degradation and can recover more quickly from disturbances. Loss of biodiversity can make soil ecosystems more vulnerable to degradation and reduce their ability to recover from disturbances. Threats to Soil Health Loss of Soil Biodiversity - Ways in which loss of soil biodiversity can affect soil health: ▪ Decreased soil carbon sequestration - soil biota, such as plants and microorganisms, play a critical role in soil carbon sequestration, which helps to mitigate climate change. Loss of biodiversity can reduce the efficiency of carbon sequestration, increasing the release of greenhouse gases into the atmosphere. Threats to Soil Health Soil Sealing - the process by which the natural properties of the soil are altered through the application of a hard and impermeable surface layer, such as concrete, asphalt, or brick - Negative impacts: ▪ Reduced water infiltration - soil sealing reduces the ability of water to penetrate the soil, leading to increased runoff and reduced groundwater recharge. Threats to Soil Health Soil Sealing - Negative impacts: ▪ Altered soil temperature and moisture - soil sealing can also alter the soil temperature and moisture regime, making it more difficult for plants to grow and for soil biota to survive. ▪ Loss of biodiversity - soil sealing can also lead to the loss of biodiversity, as the hard surface layer eliminates or reduces the area of natural habitats for plants and animals and reduces the area of soil available for growth. Threats to Soil Health Soil Sealing - Negative impacts: ▪ Reduced soil organic matter - soil sealing can also reduce the accumulation of soil organic matter, as the hard surface layer prevents the entry of organic matter into the soil and reduces the decomposition of organic matter by soil biota. ▪ Increased heat island effect - soil sealing can also contribute to the heat island effect, as the hard surface layer absorbs and retains heat, leading to increased temperatures in urban areas and reduced air quality. Threats to Soil Health Soil Compaction - reduces the porosity and pore space of the soil, making it more difficult for roots to penetrate the soil and access essential water and nutrients - can be caused by several factors, including the use of heavy machinery, overgrazing, and urbanization - Negative impacts: ▪ Reduced root growth - compacted soil makes it difficult for plant roots to penetrate and absorb water and nutrients, reducing plant growth and overall Threats to Soil Health Soil Compaction - Negative impacts: ▪ Decreased water infiltration - compacted soil has less pore space, making it more difficult for water to penetrate the soil and be absorbed by plant roots, leading to increased runoff and decreased water retention. ▪ Decreased nutrient availability - soil compaction can reduce the availability of nutrients for plant growth, as roots have more difficulty accessing them. ▪ Increased erosion - compacted soil is more prone to erosion, as it is less able to absorb and retain water. Threats to Soil Health Waterlogging - the situation where the soil remains waterlogged, or flooded, for an extended period of time - occurs when the rate of water entering the soil exceeds the rate at which water can drain out of the soil - can lead to saturation of the soil and a buildup of water in the root zone, reducing the availability of oxygen to the roots of plants and creating a stressful environment for plants to grow in Threats to Soil Health Waterlogging - Negative impacts ▪ Reduced plant growth - water logging can limit plant growth by reducing the availability of oxygen to the roots of plants, leading to root death and reduced plant growth. ▪ Increased soil salinity - water logging can also lead to increased soil salinity, as saltwater may penetrate the soil and become trapped, increasing the concentration of salts in the soil. Threats to Soil Health Waterlogging - Negative impacts ▪ Altered soil biota - water logging can affect the composition of soil biota, such as microorganisms and insects, which can disrupt the delicate balance of the soil food web and reduce soil health. ▪ Soil erosion - water logging can also increase the risk of soil erosion, as the waterlogged soil may become more susceptible to water-related erosion processes, such as overland flow and sheet erosion.