A swath of Amazon rain forest the size of England has been placed under government protection in a region known for violent conflicts among loggers, ranchers and environmentalists.

The protected territory covers 150,000 square kilometers, or 57,915 square miles, of the so-called Guayana Shield region, an area of Amazon forest stretching across international borders that contains more than 25 percent of the world's remaining humid tropical forests and the largest remaining unpolluted fresh water reserves in the American tropics.

The protected areas will link to existing reserves to form a vast preservation corridor eventually stretching into neighboring Guyana, Suriname and French Guiana. While the entire Guayana Shield corridor is not protected, portions of it in each country now are.

The Washington-based environmental group Conservation International put up $1 million to facilitate the expansion, which preserves much of the largely untouched north of the jungle. Still, it is not clear how much the new reserves will do to stall destruction in the Amazon, since most of the deforestation is taking place along the southern border of the rain forest.