VIC LEIPZIG AND LOU MURRAY:Conservation is critical to our planet’s survival

hbi-natperspectives07TextTO27E01CNatural Perspectives

The last few columns on global climate change, organic farming and sustainable living have been leading up to today’s column on the importance of conservation.

A couple of months ago, I was asked to give a talk on that topic to staff at the Orange County Conservation Corps. Vic suggested I lead off with pictures of California to show what a beautiful planet we live on. I chose a picture of Bolsa Chica and one of Yosemite. Then I defined conservation for my audience as the preservation, protection, management and restoration of the environment and its natural resources.

We have two basic kinds of natural resources: renewable and nonrenewable. Renewable resources include topsoil, trees, fish, wildlife and fresh water. Nonrenewable resources are those that are limited in supply, such as land, oil, coal, metals and other minerals. Once they’re gone, they’re gone forever.

My basic message was that if we don’t conserve what we have, eventually we will run out. If we use even renewable resources faster than they can be replaced, then we will outstrip the supply. Consequences will be extinction of plant and animal species, and even the collapse of our society if we run out of such basics as water, food or energy.

The most important crisis we are facing in this century is population growth. All other problems — global climate change, pollution, depletion of resources, habitat loss, and extinction of species — can be traced back to the problem of too many people on the planet.

The world’s population is now somewhere between 6.5 and 6.7 billion. If every couple has two children, then population will remain stable. But if every couple has four children, the world population will double in one more generation. Everything that I read about limiting factors suggests that the world cannot sustain that many people.

World population may climb to 12 billion or even higher this century. The more people we have, the less likely it is that Earth will be able to sustain them. All populations that are growing as rapidly as humans are now inevitably collapse because of some limiting factor. For people, it is likely to be fresh water or food.

Most of Earth’s water is either in oceans and too salty to drink, or is tied up in ice at the poles. Less than 1% of Earth’s water is available for our use. There will come a time when there are too many people for the available water supply. Pollution decreases available water even more.

In Southern California, we are dependent upon imported water from the Sierras and Rocky Mountains. At a time when Orange County’s population is growing, we find that our water supply is in danger of shrinking. Global climate change is expected to cause less snow in the mountains. As a consequence, rainwater will run off earlier instead of being stored in the form of snowpack that melts slowly over the spring. The population also is growing in other areas that depend upon the same water supply. More and more people will be competing for less water.

A look at the world’s food supply wasn’t any more comforting. One statistic said humans already use 40% of the sun’s energy that falls on Earth. The sun’s energy grows algae that feed fish in the ocean that we eat. It grows forests that we fell to provide wood. It grows grass and grain for livestock, and it grows the produce that we eat. If we’re really already using 40% of the sun’s energy, then the population can’t grow more than one and a half times larger than it is now. We can’t outstrip the ability of the sun to grow plants on Earth.

There was bad news about the world’s topsoil also. Although topsoil is renewable, it is being stripped away by wind and rain. Farming practices that use chemical fertilizer instead of plowing manure and green waste back into the ground deplete topsoil as well. I found an estimate based on current loss of topsoil that indicated that all of the world’s topsoil will be depleted within 70 years.

The story of the world’s fisheries wasn’t any better. We have already fished out 90% of large predatory fish. Those large fish were the breeding stock for future generations of fish. New England’s cod fisheries collapsed in the 1990s. Scientists now estimate that all of the world’s wild fisheries will have collapsed by 2050.

The world’s oil supply is in equally bad shape. In the last century, we burned up about half the world’s known oil reserves. U.S. oil production peaked in 1972 and is now declining as the last oil is being pumped out of existing wells. Experts estimate that the world’s oil reserves will be gone by 2050 to 2080. Once it is gone, there will be no more.

As our population expands rapidly, resources are being depleted at dizzying speeds. As we burn up all the oil, greenhouse gases (mainly carbon dioxide) accumulate and cause the temperature to rise.

Weather will become unstable; droughts will cause water shortages, fires and crop failures; heat waves will kill thousands of people; coral reefs will die; and coastal flooding will cause ever-increasing damage. Scientists predict that half of the world’s plant and animal species will be threatened with extinction by the end of this century.

We have always counted on technology to save us. But what if replacement technology doesn’t come in time? The solution, at least for now, is conservation. It is critical that we conserve what resources remain.

We are fortunate to live in Huntington Beach — a veritable paradise. But that paradise is supported by imported water, food and energy. Someday, the supply may run out.