Com base nos conhecimentos construídos ao longo de sua formação, redija um texto dissertativo-argumentativo em norma padrão da língua portuguesa sobre o tema “Filosofia”. Selecione, organize e relacione, de forma coerente e coesa, argumentos e fatos para defesa de seu ponto de vista. (faz sobre ética, pfv)

development:   floodplain development often directly impacts wetlands by removing vegetation (increasing bank erosion),   and filling or draining wetlands for building sites.   floodplain development sometimes indirectly impacts riparian wetlands through the installation of artificial stream stabilizing devices like rip-rap and bulk-heads that attempt to stop the natural meandering process which creates new wetlands and replenishes existing ones.    

road building:   most river valleys have roads and/or railroads.   these structures squeeze rivers and streams by narrowing the floodplain.   this destabilizes the river which   has less room to meander and therefore has an excess of energy.   the roads and railroads also affect drainage from uplands onto the floodplains, and many are built on top of areas that once were wetlands.   such roads often create long, low-quality wetlands upslope of the road by interrupting surface and groundwater flows.   these wetlands can attract wildlife dangerously close to roads.   wetland loss caused by roads is mitigated through the restoration of other impacted wetlands although the replacement wetlands are not always of the same type and quality as those lost. see montana department of transportation's off-site wetland mitigation reserves map.

grazing: overgrazing harms wetlands through soil compaction, removal of vegetation, and stream bank destabilization.   wetlands offer some of the best forage for livestock as well as a water source and cover, so livestock tends to spend a disproportionately large time in wetlands.   there are many grazing strategies that discourage cattle from using wetlands. click on rwrp's web site for a discussion of these strategies.

agriculture:   wetlands often have fairly flat areas of rich organic soil that is highly productive agricultural land if drained.   for this reason many wetlands have been drained and converted to agricultural lands.  

mining: historic mining has had a major impact on wetlands of the clark fork basin, particularly along the upper river where mine wastes have been deposited in the floodplain, creating the country’s largest superfund site. view the superfund site.  

the epa also list the following as major human causes of wetland loss:   logging,   runoff, air and water pollution, introducing nonnative species. see examples of nonnative species here.

the following lists specific damaging actions commonly taken in wetlands.

dumping:   dumping fill material buries hydric soils and effectively lowers the water table so hydrophytic (water loving) plants cannot compete with upland plants.  

            dredging:   the removal of material from a wetland or river bed.   dredging of streams lowers the surrounding water table and dries up adjacent wetlands.

            draining:   water is drained from wetlands by cutting ditches into the ground which collect and transport water out of the wetland.   this lowers the water table and dries out the wetland.    

            diverting flow:   water is diverted around wetlands, lowering the water table.  

            devegetation:   vegetation plays an important role in wetland ecology by removing water through evapotranspiration, altering water and soil chemistry, providing habitat for wildlife, and reducing erosion.   removal of vegetation can drastically and sometimes irreversibly alter wetland function.

            damming flow:   many ponds and reservoirs are constructed on wetlands.   a flooded wetland cannot provide the same habitats and functions.  

            development of springs:   pumping large quantities of water from springs lowers nearby groundwater and can result in the loss of wetland vegetation.   compaction of springs by cattle can cause springs to cease to flow.

explanation:

the article must be ratified by three-fourths (38) of states within a proscribed deadline.

source:

clearcutting reproduces a new even-aged stand by completely removing the mature stand.

clearcutting as a silvicultural treatment has several characteristics:

it causes a sudden environmental change

it removes the seed source from the regeneration area

the configuration of the clearcut may affect seed dispersal

it begins a new rotation

it will eliminate some pests that require forest cover

overall, it temporarily removes the forest cover, transforming the forest community and environment.

clearcutting followed by artificial (seeded or planted) regeneration has several advantages:

we can avoid delay in restocking the site

we can introduce a selected species, seed source, and genotype

we can control arrangement and spacing

we can achieve uniformity in the new stand

we can overcome the problems associated with securing sufficient natural regeneration.

the shelterwood method involves the removal of most of the mature stand at the end of the rotation, but a portion of the mature stand is left standing.   the shelterwood method serves three basic purposes:

to prepare the stand for production of abundant seed

to modify the environment in a way that promotes germination and survival of the selected species

to build up the amount and size of advance regeneration to ensure the prompt restocking of the new stand following overstory removal.

the shelterwood method involves a sequence of 3 cuttings:

preparatory cuttings: make the seed trees more vigorous and set the stage for regeneration. see our thinning page for more information.

establishment/seed cuttings: open up enough vacant growing space to allow establishment of the new regeneration.

removal cuttings: uncover the new crop to allow it to fill the growing space.

the residual trees in the shelterwood must:

be sturdy and windfirm

be able to survive exposure

flower and reproduce seed

be the best trees of the mature stand

keep in mind that the shelter trees must not occupy the entire site.   a void must be created in order to make room for the new regeneration. the amount of shelter to leave will depend on the following factors:

species characteristics (seeding and shelter requirements)

the number of cuttings in the cutting sequence (1, 2, or 3)

landowner objectives

the size of the area to be regenerated

the final removal harvest level required to be profitable

the shelter must be removed before it impedes the growth of the new stand or threatens its survival.

answer; the above statement is (false);