Farmland Loss Linked to Population Growth
"Urban Sprawl's Appetite for Rich Farmland" (March 21) outlines a vital issue, but largely overlooks the fundamental cause of farmland loss - rapid population growth.
The United States adds one citizen every 13 seconds, almost 2.5 million people annually. Increasing population requires increasing food production and drives farmland losses to meet demands for housing, highways, schools, parks, shopping centers, and manufacturing plants.
Since 1945, some 17 percent of the Earth's vegetated surface - an area roughly equal to India and China combined - has been moderately to severely damaged by unsustainable growing, grazing, and forestry practices. During that time, the Earth's population increased from under 2.4 billion to over 5.8 billion. With world carryover grain stocks at historical lows and some 800 million people chronically malnourished, world population is projected to grow annually by 90 million for the next 30 years.
Clearly, if global food security is to be enhanced, farmland must be protected from conversion and unsustainable production practices. But unless population growth is addressed, the future of humanity and of Earth's biota are in serious jeopardy.
Lopez Island, Wash.
Facing the Future: People and the Planet
Global warming: sharing the burden
"On Global Warming, No One Is Off the Hook" (March 24) incorrectly asserts that "US manmade carbon dioxide emissions have significantly declined over the past two decades, and will continue to decline, thanks to more energy-efficient technologies."
According to the Carbon Dioxide Information Analysis Center, US carbon dioxide emissions rose from about 1.25 billion metric tons of carbon in the mid-1970s to 1.35 billion metric tons by the early '90s. Likely, those figures are at least somewhat higher today, driven in part by higher average vehicle weight and more miles traveled per capita.
There have been gains from more efficient technologies. But they have been more than offset by population growth (US population was about 220 million in 1977 and is about 270 million today) and increased per capita use of automobiles, air travel, appliances, computers, housing space, and other things closely linked to carbon-based fuel use.
While the total keeps rising, the ratio of the US contribution to global carbon dioxide emissions indeed has declined. This, however, reflects the world catching up to our high fossil-fuel consumption rates, not technological improvement or consumption reduction on our part.
Takoma Park, Md.
The opinion-page article asks, who gains and who loses if a new treaty imposes timetables on countries to reduce emissions of heat-trapping gases? With the increase in greenhouse gases from fossil fuels largely responsible for our problems today, the answer is that all countries will gain.
But what the article misses is that for many decades, Organization for Economic Development (OECD) countries have based their economic development largely on fossil-fuel energy generation. In 1995, US carbon emissions were estimated at 5.3 tons per capita, while in China they totaled 0.7 tons.
Nobody is asking any country to immediately reduce carbon emissions. But business as usual could have disastrous consequences. It is only reasonable to place stricter targets on richer nations than on developing countries where poverty is still rampant and higher living standards are a must.
Alternatives to today's fossil fuel technologies include a combination of efficiency measures, renewable energy, and cleaner fossil-fuel technologies. Change will not come without an associated cost. But it should be looked upon as inexpensive insurance against possibly devastating climatic changes with great risk to the global environment and future economic progress.
United Nations Development Programme
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