Howdy! In this mini-lecture we will discuss the distributionof fresh water resources and major types of freshwater ecosystems. The Student Learning Objectives of this mini-lectureare:* Describe the rationing of fresh wateron Earth* Describe the major types of freshwater systems, and* Relate the ecosystem works wetlandsprovide In countless targets it seems that water resourcesare over abundant, nonetheless potable, our drinkable irrigate is quite rare and restraint. The sea on the Earth can be classified aseither fresh water, that is water that is relatively pure and which contains few dissolvedsalts, or ocean water.Ocean sea contains too many salts to drinkor use for agriculture. Merely 2.5% of all the water on Earth is freshwater, and of that only 1% is face freshwater. The vast majority of fresh water( specifically7 9 %) is inaccessible to us because it is tied up in ice caps and glaciers. It’s important to note that all the wateron the Earth is connected in a large hydrologic web. Surface water replenishes groundwater andthe movement of water from creeks, lakes and oceans meant that pollutants, sediment, organisms, scrap, and dissolved essences can be assigned from one liquid root to another. So we see that as with many other elementof the environmental issues, freshwater and marine environments fall within the scope of an interconnectedsystem. Freshwater can either be surface water orgroundwater. 20% of freshwater is groundwater, which iswater beneath the surface of the Earth held in rock and soil pore gaps. Groundwater is held in aquifers, which areporous, sponge-like patterns of boulder, sand, or gravel that hold water.A common error is that aquifers aremassive subterranean ponds. This is very rarely the action. Groundwater is usually held in pore spacesof soil and stone within the aquifer. Meaning you couldn’t depart swim in most aquifers, even if you could physically get to it. The upper seam of an aquifer is called thezone of aeration and is the area where pore openings are partially filled by water. The coating below that is the zone of saturationand is where the hole seats are wholly filled with water. The boundary between these two zones is calledthe water table. Aquifers are recharged when surface waterruns over a recharge area, which is the above ground land area that allows surface waterto infiltrate into the aquifer below. The world’s largest known aquifer is the Ogallalaaquifer, is located within the Great Plateau of the U.S. This aquifer has equipped farmers and rancherswith water for generations, nonetheless unsustainable withdrawals are threatening this aquifer, and many other aquifers. Groundwater can be easily sapped and aquifersrecharge slowly.There are several ramifications to overdrawingan aquifer: 1. Water tables fell, spawning it harder to extractwater from the aquifer; 2. Wetlands dry up; 3. Water becomes rarer and more costly; 4. If the aquifer is in a coastal region saltwater will intrude into the freshwater aquifer; 5. Land will subside or subside; and6. Soil will become compacted, lose porosity, eventually shaping recharge harder. You be remembered that a watershed is an areaof land where all the water that appears in it, or falls within it, drains off into a singularoutlet. In other terms a watershed is the area ofland drained by a flow structure. A river organisation is a river and all of its tributaries. Tributaries are smaller flows or streamsthat spring into the main river. Watersheds are also welcome to now called drainage basin. Remember that everyone lives in a watershed. If you’d like to find out what watershed youlive in you can follow the link I’ve provided in the this week’s folder. We will now consider the major types of freshwatersystems. The first of these systems we will consideris a floodplain.A floodplain is defined as the shore alongsidea flow. Floodplains are at the bottom of depressions andare surrounded by uplands, or territories with higher raising. When the river inundates, it situates silt, gravel, and clay onto the floodplain. This action originates the grime of floodplainsvery fertile. Hence floodplains are commonly usedfor agriculture. Another major type of freshwater system isa riparian area. This is the land along the banks of a riveror stream. Riparian fields are the transitional areasbetween the aquatic organisation of the river and the terrestrial ecosystem on land.Riparian neighborhoods are comprised of the vegetation thatgrows along the banks of the river. As with most transitional zones, or the zonesbetween two different ecosystems, riparian ecosystems are known for being productiveand species-rich. Lake and pond are patently another typeof freshwater system. Pool and ponds are standing water with distinctzones. The nutrient rich boundaries of the ocean form, where the irrigate is shallow enough to allow aquatic weeds to grow is called the littoralzone.This region has a rich diversity of organismsincluding aquatic invertebrates such as insects, snails and crawfish, as well as vertebratessuch as fledglings, fish, turtles and amphibians. The limnetic zone is the open segment of thelake that is shallow enough to allow sunlight to penetrate its part magnitude. The sunlight enables photosynthesis to occurin this zone, which makes this area is teeming with photosynthetic phytoplankton such asalgae, protists, and cyanobacteria.Beneath the limnetic area, is the profundalzone. This sphere of the pool is the open waterof the pool that is too deep to allow light to reach it. For these considerations, the profundal area does nothave photosynthetic creatures and thus the dissolved oxygen levels are lower in thiszone compared to the limnetic area. The benthic region of a pond is the portionthat gives along the very freighter, from the coast to the deepest point. Invertebrates that live in this zone are calledbenthic invertebrates and are often studied to assess the health of the aquatic organization. Ponds and lakes evolve over time as they receivesediment and nutrient inputs. Oligotrophic lakes and ponds have low-toned nutrientcontent and high-pitched oxygen conditions.These reservoirs appear clear and are aid a varietyof organisms. Oligotrophic lakes can be converted into eutrophiclakes, who the hell is lakes with high nutrient and low-toned oxygen cases. The process of eutrophication is natural. For countless lagoons, as they age over centuries, there is a buildup of nutrients, sediment, and flower fabric, which slowly crowd thelake basin. Eventually, the process ends and the basinbecomes colonized by terrestrial vegetation.The timing of natural eutrophication is highlyvariable and depends on the characteristics of the basin, watershed, and climate. However, humans, by altering nutrient inputs, have greatly increased the speed at which eutrophication can be produced. The final type of freshwater system we willexamine a wetland. Wetlands are areas where the soil is saturatedwith shallow, abide ocean. Wetlands have an abundance of botany andare considered to be very diverse and beneficial ecosystems. Wetlands provision valuable environment to aquaticand terrestrial creature, such as migratory birds. Wetland render valuable ecosystems servicessuch as slow-witted runoff, abbreviating flooding, recharging aquifers, and filtering pollutants. Historically, people have drained wetlands, principally for agricultural purposes. For perspective, the Southern U.S. and Canadahave lost over half of their wetlands since European Colonization. One of the main reasons Hurricane Katrinawas so devastating was because Louisiana drained and developed the majority of its coastalwetlands. These wetlands act as a buffer to cyclones, tempering the squall surges that reached the coastal moods. Nonetheless, when the coastal wetlands are removed, the tornado upsurge can reach much further inland and generate significantly more damage than ifthe wetlands had been in place.There are a variety of types of wetlands: Freshwater marshes are usually at mouths of creeks and have shallow water and vegetationthat develops above the surface of the ocean, such as cattails and bulrushes. Large pulls of freshwater marshes spanmuch of the Florida Everglades. Swamps are wetlands in forested provinces, suchas the drenches of Louisiana. Bogs are ponds covered in thick moving matsof botany and may be a transitional stage of aquatic inheritance. Ultimately, vernal funds are seasonal wetlandsthat exist only during moisture portions of the year. As an environmental scientists, if your jobis to evaluate wetlands you must be aware of land that can serve as a wetland, evenif it is only during a portion of the year. You can learn more about wetlands by takingEcosystem Science and Management( ESSM) 440. In this class you’re learn how to delineate, or assess the size and scope of a wetland, and you’ll learn how to realize jurisdictionaldeterminations related to wetlands.This is a highly marketable and useful classif you plan on going into environmental consulting. That concludes the first mini-lecture on thedistribution of fresh water resources and major types of freshwater ecosystems. Please review the weekly summary and completethe activities for this week per the schedule set forth in the outline. Thanks and Gig’ Em ..