What are the two biggest direct threats to our natural world? One could debate this question endlessly but here are my personal candidates for two recent developments that are especially environmentally perilous:

1) The G20's stunning plans for infrastructure expansion

Believe it or not, the leaders of the G20 nations -- the world's 20 largest economies -- committed during their recent global summit in Brisbane, Australia to spend an astonishing 60-70 trillion U.S. dollars on new infrastructure projects by the year 2030.

This staggering sum will come from a variety of sources, such as public-private partnerships, pension funds, bilateral aid, and the major development banks. This will be the single biggest financial transaction in human history -- and the environmental impacts will be Earth-shaking.

Expect massive increases in roads, hydroelectric dams, mining projects, gas lines, and power lines, all across the planet. Such projects will open up many of the world's last surviving wild areas and lead to an avalanche of new development pressures.

2) The rise of the Chinese and Brazilian development banks

An equally alarming trend is that the nature of infrastructure funding is changing.

Large funding bodies such as the World Bank and the African, Asian, and Inter-American Development banks -- which, after many years of bearing criticism, have worked to develop and implement some environmental safeguards -- are increasingly being supplanted by the heavily funded and far more aggressive Chinese (AIIB) and Brazilian (BNDES) development banks.

We've previously critiqued BNDES, but the Chinese-dominated Asian Infrastructure Investment Bank is, arguably, even worse.

The Chinese and Brazilian banks are funding massive numbers of developments worldwide, and generally place a much lower priority on environmental concerns than do many other infrastructure funders and donors.

Conservationists and scientists will have to redouble their efforts to meet the challenges posed by these two landmark -- and alarming -- trends.

-Bill Laurance

The world's two most dangerous environmental trends