Wetlands

Wetlands

1. i) Research on the internet about characteristics of Wetlands

An area is categorized as a wetland if at least 12 inches of the soil surface is saturated with water for a period exceeding 15 days. The wetlands are characterized by hydric soils. The soil grain spaces within the hydrologic soils are filled with water. The soil color in the wetlands is characterized by a darkish brown appearance which indicates the presence of organic materials. These soils contain different minerals and are referred to Gleysols (Holland et al, 2017). Due to prolonged soil saturation by the groundwater in the presence of organic materials, wetlands have reduced iron minerals that are partly leached out of the soil. The leached iron forms an olive, blue or grey coloured subsoil horizon that can be seen in most wetlands. Sometimes, soil in the wetlands might have a rotten egg smell due to the presence of Sulphur. The wetlands characteristics may vary due to differences of climatic conditions, topography, vegetation and soils from one region to another. For example, coastal or tidal wetlands have different characteristic from inland or non-tidal wetlands. Coastal wetlands are characterized by low vegetation as the soils. The salty water in coastal wetlands makes it difficult for most plant and animal species to survive even when the surface is well saturated with water all year round. The inland wetlands are different as the soil, and water quality allows for the growth of different plant and animal species even if the species can vary from one region to another.

1. ii) Research on the internet about characteristics of Raingardens

Rain gardens are characterized by residential development and commercial industrial development. The soil characteristics in a rain garden are typically hydrologic soils due to the characteristics of holding rainwater for long periods of time. The spaces in the soil grains are separated by water for certain periods of time depending on the type and purpose of the rain garden. The rain gardens are best suited in areas where the infiltration is at least o.5 inches/hour for moderate permeability and controlled infiltration (Autixier et al, 2016). The rain gardens depend on deep-rooted vegetation that opens up the subsoils to improve penetration.

1. i) Outline the importance of wetlands environment to the natural and human environment, providing examples.

Wetlands act as barriers to waves actions protecting human settlements from floods. Wetlands like rain gardens provide water treatment quality by absorbing water pollutants. For example, industries use wetlands to improve water quality. In Australia, wetlands have been used as fish nurseries that are critical to the countries commercial industry. To the natural environment, wetlands provide an habitant to animals and plants that are adapted to live in hydrologic soils. These plants and animals cannot be found anywhere else and depend on the wetlands for their survival. An example of animals adapted to wetlands is muskrat and wood ducks that can only survive on inland wetlands.

1. ii) Define the term ‘wetlands’ & describe the characteristics which make it a place a ‘true wetland’?

Wetlands are areas that have free water which is present on the surface for at least the major part of a vegetation growth season. The water in the wetlands covers the soil or can be present on the surface or near the surface all year round, including the major growing season. A true wetland is made of a distinct ecology of vegetation adapted to wetlands, distinct surface water hydrology, animal species that are only adapted to wetland areas and climatic conditions. In this case, the primary characteristics that define a true wetland are the vegetation characteristics that are only adapted to those areas and the animal species that are adapted to the unique wetlands hydrologic soils.

iii) Define the term ‘rain garden’ & describe the characteristics that could make it a rain garden?

A rain garden is a relatively shallow depression that is constructed in the ground to act as an infiltration point for rainwater coming from the roof or other clean surfaces. The rain garden is characterized by hydrologic soils. They are made of a variety of trees, shrubs and vegetation that are adapted to hydrologic soils. The rain gardens can be classified into three categories depending on the soil water infiltration rate. Infiltration rain gardens have an infiltration rate of 0.5 inches/hour. Partial infiltration rain gardens have an infiltration rate of less than 0.5 and a filtration rain garden does not hold water but provides water treatment quality only.

4. What defines a place to be a true wetland or a rain garden?

True wetlands are defined by the characteristics of the soil and the vegetation. For an area to be categorized as a true wetland, the top 12 inches of soil must be saturated with water for not less than a period of 15 days. Wetland and rain garden ecology characterize these areas by their surface water soil hydrology, the vegetation, terrain characteristics and the existing climatic conditions. The water hydrology in a rain garden or a wetland determines the type of vegetation or animal species that can live or be adapted to the wetlands (Holland et al, 2017). For wetlands and rain gardens, long periods of water saturation create the conditions that favour vegetation growth and promotes the hydrologic soil characteristics of wetlands and rain gardens.

References

Autixier, L., Mailhot, A., Bolduc, S., Madoux-Humery, A. S., Galarneau, M., Prévost, M., & Dorner, S. (2014). Evaluating rain gardens as a method to reduce the impact of sewer overflows in sources of drinking water. Science of the total environment, 499, 238-247. Holland, M. M., Whigham, D. F., & Gopal, B. (1990). The characteristics of wetland ecotones. The ecology and management of aquatic-terrestrial ecotones, 171-198. 

Holland, M. M., Whigham, D. F., & Gopal, B. (2017). The characteristics of wetland ecotones. The ecology and management of aquatic-terrestrial ecotones, 171-198.