Columbia subject headings:
Amazon River Region--Environmental conditions.
Ecuador--Environmental conditions.
Environmental indicators--Amazon River Region.
Environmental indicators--Ecuador.
Environmental monitoring--Amazon River Region.
Environmental monitoring--Ecuador.
Environmental protection--Amazon River Region.
Environmental protection--Ecuador.
Petroleum industry and trade--Environmental aspects--Amazon River Region.
Petroleum industry and trade--Environmental aspects--Ecuador.
Harvard subject headings:
Amazon River Region--Environmental conditions.
Ecuador--Environmental conditions.
Environmental indicators--Amazon River Region.
Environmental indicators--Ecuador.
Environmental monitoring--Amazon River Region.
Environmental monitoring--Ecuador.
Environmental protection--Amazon River Region.
Environmental protection--Ecuador.
Petroleum industry and trade--Environmental aspects--Amazon River Region.
Petroleum industry and trade--Environmental aspects--Ecuador.
Princeton subject headings:
Amazon River Region--Environmental conditions.
Ecuador--Environmental conditions.
Environmental indicators--Amazon River Region.
Environmental indicators--Ecuador.
Environmental monitoring--Amazon River Region.
Environmental monitoring--Ecuador.
Environmental protection--Amazon River Region.
Environmental protection--Ecuador.
Petroleum industry and trade--Environmental aspects--Amazon River Region.
Petroleum industry and trade--Environmental aspects--Ecuador.