FOR most people, ''refugees'' means tattered masses fleeing war, religious persecution, repressive government, or some combination of these horrors. From Afghanistan to Rwanda to Guatemala they now total about 22 million people around the world, about twice as many as a decade ago.
But there is another category of persons forced to leave home that may be reaching even more staggering proportions, and it's just now getting the kind of attention it should.
These are ''environmental refugees,'' those uprooted because of soil erosion, deforestation, water shortages, desertification, and other conditions tied to land and its resources. And according to a new study by Norman Myers of Oxford and Cornell universities, the rapidly increasing number of these refugees - now 25 million, or more than the other traditional categories combined - could double over the next 15 years.
Dr. Myers's work is sponsored by the Climate Institute and supported by private foundations, the United Nations, and government agencies in the United States, Great Britain, and Sweden. It comes at a time when the better-off world seems to be suffering from a two-pronged attack of ''compassion fatigue'' and immigrant bashing. But to ignore or deny the troubling situation detailed here will only make matters worse.
The figures are numbing: Some 135 million people live in areas threatened with desertification, and 550 million face chronic water shortages. Of the 1.3 billion people who constitute the poorest in the world (average income of no more than $1 a day), some 70 percent live on marginal land unable to sustain agriculture.
And yet right up until they finally are forced to leave, these potential refugees continue to impact the landscape - with little alternative, since they have been bypassed by national or international development efforts and in essence have become marginalized themselves.
In a paper on refugees and migrants published last month, Hal Kane of the Worldwatch Institute writes on how this creates a cycle of poverty and environmental degradation: ''Felled trees ... no longer anchor soil, which washes away and clogs rivers, and the disrupted flows of water cause further soil erosion and disrupt harvests of fish. In rural areas where people directly depend on the soil and water and forests for sustenance, poverty is essentially an environmental trend.''
''These people are usually cash poor, yet so long as they are natural-resource rich, they can remain home and prosper,'' Mr. Kane continues. ''But when people flee poverty they are often fleeing environmental impoverishment - after the topsoil blew away or the well ran dry - in places without a rural economy that can offer them alternative sources of livelihood.''
As with the other things that drive people to become refugees, a worn-out environment usually comes in combination with some other problem. Like overpopulation, which continues to cause abuse of resources despite declining birth rates in some parts of the developing world. Or ethnic strife, which itself can be generated by diminishing resources.
Although solutions may not be easy, they are basic. Like expanding international population programs and redirecting foreign aid to the 1.3 billion poorest of the poor (who today receive far less than half of total aid).
Of course, leaders in developing countries themselves have an important role to play. But it's not something that can be dismissed by those of us fortunate enough to be able to stay put if we want to (and who have our own problems of overconsumption and the promotion of environmentally damaging development abroad to face up to).
Either we or our offspring will have to address the plight of environmental refugees.
The better-off world seems to be suffering from 'compassion fatigue' and immigrant bashing. But to ignore the situation makes matters worse.