Self Evaluation Quiz - Water Quality And Analyses

Explanation
The water cycle is driven by the earth's gravity and the sun. The sun provides energy to heat the Earth's surface, causing water to evaporate from oceans, lakes, and rivers. This water vapor rises into the atmosphere. Gravity then plays a crucial role in the water cycle by pulling the water vapor back down to the Earth as precipitation, such as rain or snow. This process of evaporation, condensation, and precipitation is continuously occurring due to the combined influence of gravity and the sun's energy, ensuring the continuous circulation of water on Earth.

Explanation
Green water refers to soil moisture in the unsaturated soil layer that is available to plants. This moisture is absorbed by plant roots and used for photosynthesis and growth. It is called green water because it is essential for the growth and productivity of vegetation, contributing to the greenness of plants. Green water is different from blue water, which refers to water in rivers, lakes, and aquifers, and underground water, which is water stored below the Earth's surface. Crop moisture is not a commonly used term and does not accurately describe soil moisture available to plants.

Explanation
Approximately 97% of the total amount of water on Earth is found in the oceans and other saline water bodies. This is because the oceans cover a vast majority of the Earth's surface and contain a significant amount of water. The remaining 3% is freshwater, which is found in lakes, rivers, ice caps, and underground sources.

Explanation
Water with a dissolved salt content of 45ppt is classified as saline water. Saline water contains a higher concentration of salt compared to fresh water and brackish water. This level of salt content makes it unsuitable for drinking and irrigation purposes. Saline water is commonly found in oceans, seas, and saltwater lakes.

Explanation
Surface water is generally softer compared to other sources such as groundwater. This is because surface water is constantly moving and flowing, which helps to naturally remove minerals and impurities that can make water hard. Hard water contains high levels of calcium and magnesium, which can cause scale buildup in pipes and appliances. Softer water is preferable for many uses, as it reduces the need for water softening treatments and extends the lifespan of plumbing systems and appliances.

Explanation
The statement "The total amount of earth's water varies with time" is false. The total amount of water on Earth remains relatively constant over time due to the water cycle, where water is continuously recycled through processes such as evaporation, condensation, and precipitation. While the distribution of water may change in different forms (solid, liquid, gas) and locations (oceans, ice caps, underground reservoirs), the overall amount of water on Earth remains relatively stable.

Explanation
Groundwater is generally preferable to surface water in terms of quality because it is naturally filtered as it passes through layers of soil and rock. This filtration process helps remove impurities and contaminants, resulting in cleaner and purer water. Surface water, on the other hand, is more susceptible to pollution from various sources such as industrial runoff, agricultural activities, and urban development. Therefore, in terms of overall quality, groundwater is considered a better option for drinking and other purposes.

Explanation
The geology of the underlying bedrock can indeed affect the quality of groundwater. Different types of bedrock can have varying levels of permeability, which can impact the movement and filtration of water through the ground. For example, porous bedrock like sandstone or limestone can allow water to flow more easily and may result in higher-quality groundwater. On the other hand, impermeable bedrock like clay or shale can hinder the movement of water and may lead to lower-quality groundwater. Therefore, the geology of the underlying bedrock is an important factor to consider when assessing the quality of groundwater.

Explanation
The presence of organics in water can actually affect the dissolved oxygen levels. Organic matter can decompose, consuming oxygen in the process. This can lead to lower dissolved oxygen levels in the water, which can negatively impact aquatic life. Therefore, the statement that the presence of organics in water does not affect the dissolved oxygen is false.

Explanation
Changes in temperature can indeed have a significant impact on the quality of a water body. Temperature affects various factors such as dissolved oxygen levels, nutrient availability, and the growth and reproduction of aquatic organisms. For example, warm water holds less dissolved oxygen, which can lead to oxygen depletion and harm aquatic life. Temperature changes can also disrupt the balance of ecosystems, causing shifts in species composition and potentially leading to the proliferation of harmful algal blooms. Therefore, it is true that the changes in temperature with the local environment of a water body can affect its quality.