quarta-feira, 8 de julho de 2009

Conservar nascente em pequenas bacias hidrográficas

Nascentes são manifestações superficiais de água armazenada em reservatórios subterrâneos, conhecidos como aquíferos ou lençóis, e que dão origem a pequenos cursos d’água. Estes pequenos constituem os córregos que se ajuntam para formar riachos e ribeirões e que voltam a se juntar para formar os rios. É assim que surge tanto um pequeno ribeirão, quanto os rios Amazonas e São Francisco, e tantos outros.

Mas nem todas as manifestações superficiais dos lençóis subterrâneos chegam a formar cursos d’água, pois podem ficar simplesmente formando poças e constituindo as conhecidas fontes. Já os lençóis são abastecidos pela parte da água das chuvas que penetra no solo e desce pelo perfil do mesmo até encontrar uma camada impermeável (rochosa, por exemplo). Com a impossibilidade de continuar descendo, ela se acumula, preenchendo os poros, encharcando ou saturando o solo logo acima da referida camada impermeável. Esse volume de solo saturado constitui o lençol ou aquífero.

A conservação de nascentes é, portanto, uma tecnologia que precisa estar baseada em fundamentos hidrológicos. Sobre tais fundamentos, que variam com a variação dos ecossistemas, é que são estabelecidas as tecnologias de manejo. Toda a parte do ciclo hidrológico envolvida na conservação de nascentes ocorre numa área da superfície que se enquadra na definição de bacia hidrográfica. Pode ser pequena, uma simples grota, e aí está o segredo de tudo, pois a hidrologia de pequenas bacias tem peculiaridades que a difere daquela usada nos estudos de grandes rios, para construção de hidrelétricas, por exemplo.

Artigo do Professor Osvaldo Ferreira Valente. Engenheiro florestal, especialista em hidrologia e manejo de pequenas bacias hidrográficas e professor titular da Universidade Federal de Viçosa (UFV) / ovalente@tdnet.com.br. Do jornal O ECO http://www.oeco.com.br/

8 comentários:

Anônimo disse...

[u][b]Xrumer[/b][/u]

[b]Xrumer SEO Professionals

As Xrumer experts, we possess been using [url=http://www.xrumer-seo.com]Xrumer[/url] for a wish immediately for the time being and grasp how to harness the massive power of Xrumer and turn it into a Bills machine.

We also yield the cheapest prices on the market. Diverse competitors desire expect 2x or temperate 3x and a end of the term 5x what we pervade you. But we believe in providing great mending at a low affordable rate. The large incidental of purchasing Xrumer blasts is because it is a cheaper surrogate to buying Xrumer. So we aim to support that thought in recollection and afford you with the cheapest rate possible.

Not solitary do we have the best prices but our turnaround time for your Xrumer posting is super fast. We intention have your posting done in the forefront you know it.

We also produce you with a ample log of successful posts on contrasting forums. So that you can get the idea for yourself the power of Xrumer and how we have harnessed it to help your site.[/b]


[b]Search Engine Optimization

Using Xrumer you can trust to see thousands upon thousands of backlinks over the extent of your site. Myriad of the forums that your Site you intent be posted on bear great PageRank. Having your join on these sites can truly help build up some cover quality recoil from links and really riding-boot your Alexa Rating and Google PageRank rating through the roof.

This is making your position more and more popular. And with this inflate in regard as grammatically as PageRank you can envisage to lead your area absolutely downright gamy in those Search Motor Results.
Transport

The amount of transportation that can be obtained by harnessing the power of Xrumer is enormous. You are publishing your locality to tens of thousands of forums. With our higher packages you may even be publishing your locale to HUNDREDS of THOUSANDS of forums. Create 1 post on a in demand forum drive almost always get 1000 or so views, with say 100 of those people visiting your site. Now create tens of thousands of posts on fashionable forums all getting 1000 views each. Your see trade ordain function through the roof.

These are all targeted visitors that are interested or bizarre nearly your site. Deem how innumerable sales or leads you can fulfil with this considerable gang of targeted visitors. You are truly stumbling upon a goldmine friendly to be picked and profited from.

Reminisce over, Above is Money.
[/b]

GO YOUR CHEAP DEFAME TODAY:


http://www.xrumer-seo.com

Anônimo disse...

Away with aside Our Ward Prices at www.Pharmashack.com, The Election [b][url=http://www.pharmashack.com]Online Chemist's boutique [/url][/b] To [url=http://www.pharmashack.com]Buy Viagra[/url] Online ! You Can also Espy In the chips Deals When You [url=http://www.pharmashack.com/en/item/cialis.html]Buy Cialis[/url] and When You You [url=http://www.pharmashack.com/en/item/levitra.html]Buy Levitra[/url] Online. We Also Be subjected to a Vast Generic [url=http://www.pharmashack.com/en/item/phentermine.html]Phentermine[/url] In subordinate of Your Regimen ! We Snake moderate up Sphere signpost [url=http://www.pharmashack.com/en/item/viagra.html]Viagra[/url] and Also [url=http://www.pharmashack.com/en/item/generic_viagra.html]Generic Viagra[/url] !

Anônimo disse...

Predilection casinos? wrench this nippy [url=http://www.realcazinoz.com]casino[/url] captain and convey mad up online casino games like slots, blackjack, roulette, baccarat and more at www.realcazinoz.com .
you can also ascendancy up our untrained [url=http://freecasinogames2010.webs.com]casino[/url] orientate at http://freecasinogames2010.webs.com and be beneficiary to in crap tangled dough !
another swaggerer [url=http://www.ttittancasino.com]casino spiele[/url] more is www.ttittancasino.com , because german gamblers, submit c be communicated nearby manumitted online casino bonus.

Anônimo disse...

Someone deleted several links from storewith and hotfile servers.

From now, we will use www.tinyurlalternative.com as our main [url=http://www.tinyurlalternative.com]url shortener[/url], so every url will be there and visible for everyone.

You can choose from several great [url=http://kfc.ms]short url[/url] address like:

kfc.ms easysharelink.info jumpme.info megauploadlink.info megavideolink.info mygamelink.info myrapidsharelink.info mytorrentlink.info myurlshortener.com mywarezlink.info urlredirect.info urlshrinker.info weblinkshortener.com youtubelink.info and many others.

They maintain above 60 other ready domains and the [url=http://myurlshortener.com]url shortener[/url] service work well for free without any registration needed.

So we think it is good idea and suggest you to use [url=http://urlredirect.info]url redirect[/url] service too!

Thank you.

Anônimo disse...

You could easily be making money online in the underground world of [URL=http://www.www.blackhatmoneymaker.com]blackhat community[/URL], It's not a big surprise if you haven’t heard of it before. Blackhat marketing uses alternative or not-so-known avenues to generate an income online.

Anônimo disse...

http://www.pornvideoonline.info

http://www.pornvideodownload.info/

www.pornvideotorrent.info

http://www.gaypornonline.info

http://www.teenpornonline.info

http://www.freepornvideosonline.info/

http://www.bestpornvideo.info/

[url=http://www.pornvideoonline.info]Porn video online[/url]
[url=http://www.pornvideodownload.info]Porn video download[/url]
[url=http://www.pornvideotorrent.info]Porn video torrent[/url]
[url=http://www.gaypornonline.info]Gay porn online[/url]
[url=http://www.teenpornonline.info]Teen porn online[/url]
[url=http://www.freepornvideosonline.info]Free porn videos online[/url]
[url=http://www.bestpornvideo.info]Best porn video[/url]

Anônimo disse...

http://site.ru - [url=http://site.ru]site[/url] site
site

Anônimo disse...

The stuff іs suppoѕed to be an antidοte to "Erectile Dysfunction in Men. Well, as I sit in front of the tube on any given night to get my N. Unlike Viagra, it can help you get erections even when you have other health problems such as heart diseases, kidney or liver problems.

Stop by my site :: cialis alcohol