Central asia landscapes and ecology

TASHKENT INSTITUTE OF IRRIGATION AND AGRICULTURAL MECHANIZATION ENGINEERS

“EcoGIS” CENTER

CENTRAL ASIA LANDSCAPES AND ECOLOGY

REPORT

Under the theme: WETLANDS ECOSYSTEM

Prepared by: Djalgasbayeva Ayman

Approved by: Khasanov Saidjakhon

TASHKENT-2020

OUTLINE

Introduction

Wetlands ecosystem

Ramsar Convention

Conclusion

List of references

Introduction

Wetlands are parts of our landscape that are defined by the presence of water. More specifically, wetlands are areas where the presence of water determines or influences most, if not all, of an area's biogeochemistry—that is, the biological, physical, and chemical characteristics of a particular site.



Wetlands ecosystem

Many wetlands are transitional zones between upland and aquatic ecosystems, although others are scattered across the landscape in upland depressions that collect water or in zones where groundwater comes to the surface.

The amount of water present in a wetland can vary greatly. Some wetlands are permanently flooded, while others are only seasonally flooded but retain saturated soils throughout much of the unflooded period. Still other wetlands may rarely flood, but saturated soil conditions still are present long enough to support wetland-adapted plants and for hydric soil characteristics to develop. Hydric soils develop when chemical changes take place in the soil due to the low-oxygen conditions associated with prolonged saturation.

Different plant communities may be found in different types of wetlands, with each species adapted to the local hydrology (the quantity, distribution, and movement of water throughout a given area). Wetland plants are often referred to as hydrophytes because they are specially adapted to grow in saturated soils. Many birds, insect, and other wildlife species are completely dependent on wetlands for critical stages in their life cycles, while many other species make use of wetlands for feeding, resting, or other life activities.

Role of salinity

Salinity has a strong influence on wetland water chemistry, particularly in wetlands along the coast. In non-riverine wetlands, natural salinity is regulated by interactions between ground and surface water, which may be influenced by human activity.

Soil

Carbon is the major nutrient cycled within wetlands. Most nutrients, such as sulfur, phosphorus, carbon, and nitrogen are found within the soil of wetlands. Anaerobic and aerobic respiration in the soil influences the nutrient cycling of carbon, hydrogen, oxygen, and nitrogen, and the solubility of phosphorus thus contributing to the chemical variations in its water. Wetlands with low pH and saline conductivity may reflect the presence of acid sulfates and wetlands with average salinity levels can be heavily influenced by calcium or magnesium. Biogeochemical processes in wetlands are determined by soils with low redox potential.

Biota

The biota of a wetland system includes its vegetation zones and structure as well as animal populations. The most important factor affecting the biota is the duration of flooding.  Other important factors include fertility and salinity. In fens, species are highly dependent on water chemistry. The chemistry of water flowing into wetlands depends on the source of water and the geological material in which it flows through has well as the nutrients discharged from organic matter in the soils and plants at higher elevations in slope wetlands. Biota may vary within a wetland due to season or recent flood regimes.

Flora

There are four main groups of hydrophytes that found in wetland systems throughout the world. Submerged water plants. This type of vegetation is found completely underwater. Submerged wetland vegetation can grow in saline and fresh-water conditions. Some species have underwater flowers, while others have long stems to allow the flowers to reach the surface. Submerged species provide a food source for native fauna, habitat for invertebrates, and also possess filtration capabilities. Examples include seagrasses and eelgrass.

Floating water plants. Floating vegetation is usually small although it may take up a large surface area in a wetland system. These hydrophytes have small roots and are only found in slow-moving water with rich-nutrient level water Floating aquatic plants are a food resource for avian species. Examples include water lilies lily pad and duckweed.

Emergent water plants. Emergent water plants can be seen above the surface of the water but whose roots are completely submerged. Many have aerenchym to transmit oxygen from the atmosphere to their roots. Extensive areas of emergent plants are usually termed marsh. Examples include cattails (Typha) and arrow arum (Peltandra virginica).

Surrounding trees and shrubs. Forested wetlands are generally known as swamps. The upper level of these swamps is determined by high water levels, which are negatively affected by dams. Some swamps can be dominated by a single species, such as silver maple swamps around the Great Lakes. Others, like those of the Amazon Basin, have large numbers of different tree species. Examples include cypress (Taxodium) and mangrove.

Fauna

Fish: Fish are more dependent on wetland ecosystems than any other type of habitat. 75% of the United States’ commercial fish and shellfish stocks depend solely on estuaries to survive. Tropical fish species need mangroves for critical hatchery and nursery grounds and the coral reef system for food.

Amphibians: Frogs are the most crucial amphibian species in wetland systems. Frogs need both terrestrial and aquatic habitats in which to reproduce and feed. While tadpoles control algal populations, adult frogs forage on insects. Frogs are used as an indicator of ecosystem health due to their thin skin which absorbs both nutrient and toxins from the surrounding environment resulting in an above average extinction rate in unfavorable and polluted environmental conditions.

Reptiles: Alligators and crocodiles are two common reptilian species. Alligators are found in fresh water along with the fresh water species of the crocodile. The saltwater crocodile is found in estuaries and mangroves and can be seen in the coastline bordering the Great Barrier Reef in Australia. The Florida Everglades is the only place in the world where both crocodiles and alligators co-exist.^[1]Snakes, lizards, goannas, and turtles also can be seen throughout wetlands. Snapping turtles are one of the many kinds of turtles found in wetlands.

Mammals: Multiple small mammals as well as large herbivore and apex species such as the Florida Panther live within and around wetlands. The wetland ecosystem attracts mammals due to its prominent seed sources, invertebrate populations, and numbers of small reptiles and amphibians.

Monotremes: The platypus (Ornithorhynchus anatinus) is found in eastern Australia living in freshwater rivers or lakes, and much like the beaver creates dams, create burrows for shelter and protection. The platypus swims with webbed feet. Platypuses feed on insect larvae, worms, or other freshwater insects hunting mainly by night by the use of their bill. They turn up mud on the bottom of the lake or river, and with the help of the electroreceptors located on the bill, unearth insects and freshwater insects. The platypus stores their findings in special pouches behind their bill and consumes its prey upon returning to the surface.

Insects and invertebrates: These species total more than half of the 100,000 known animal species in wetlands. Insects and invertebrates can be submerged in the water or soil, on the surface, and in the atmosphere.

Algae are diverse water plants that can vary in size, color, and shape. Algae occur naturally in habitats such as inland lakes, inter-tidal zones, and damp soil and provide a dedicated food source for animals, fish, and invertebrates. There are three main groups of algae:

Plankton are algae, which are microscopic, free-floating algae. This algae is so tiny that on average, if fifty of these microscopic algae were lined up end-to-end, it would only measure one millimeter. Plankton are the basis of the food web and are responsible for primary production in the ocean using photosynthesis to make food. Filamentous algae are long strands of algae cells that form floating mats. Chara and Nitella algae are upright algae that look like a submerged plant with roots.