Globally, there are no practical methods of controlling trends in any of the 20 areas mentioned.

Optimists and academics may prescribe solutions, but the current situation has been reached by consensual compromise, not by deliberate malice. As pressures build, with apparent climate change, the same process of compromise will determine the priorities of behavioural change required to ameliorate the less pleasant effects.

As always, the rich will sacrifice the wellbeing of the poor to maintain a differential in comfort and lifestyle probably not dissimilar to that existing today. The world has never cared for poor and the currently predicted dilemmas will not alter this attitude.

As a species, we will all sit and watch events unfold; appropriate rhetoric will assist in absolving feelings of responsibility and ensure inaction maintains top priority.

Stephen Davey, Sydney, Australia

Looked at logically, most of these factors seem to cancel each other out.

Worried about a population of 9.5 billion by 2050? Between conflicts, water shortages, food shortages and air pollution, the study projects at least 13 million annual deaths over and above other causes (disease, age, accident, etc.). Factor in the studies showing that countries in the First and Second Worlds are falling below the replacement level in birth/death ratios (2.3 births per death), and somehow I suspect that this prediction is as erroneous as those in Dr. Paul Ehrlich's "The Population Bomb" in 1971.

As for food consumption, how can it go up if the population declines? And regarding insects destroying crops, considering that it was the UN that helped impose a ban on insecticides like DDT, thereby causing insect populations that were once controlled to explode again in the last 30 years, whose fault is that?

All of the above leads me to wonder if the UN itself isn't a threat to our survival.

eon

eon, Lancaster,

I wholeheartedly agree that population must be the target. The population of the western world, which constitutes the greatest threat to the environment due to over-consumption of resources, should be restricted by immediate governmental and UN agreed restriction on births and immigration.

I would also endorse the immediate restriction of the spread of the population of CEO's of global corporations who have no concern for more than the population of their shareholders, to the detriment of the remainder of the world's population.

We could also consider a population cull of corrupt dictators, totalitarian world leaders, and western govermental officials who encourage and support them for their own gain.

CO2 increase is the faeces of our consumptive greed. Are we more intelligent than yeast?

Dr. David Mead

Dr. David Mead, Findhorn, Forres, Moray, Scotland

Population is the key - all the other factors are mere side-effects of population. Fiddling about with environmental legislation and tinkering about at the edges is entirely futile if the population is allowed to increase without constraint. Indeed, as can be seen, if we don't take steps to decrease the population - it'll be forced upon us through starvation, disease and conflict.

John, London, UK,

Unfortunately, probably very few of our leaders have been trained in biology, so the term "carrying capacity" has no meaning to them. In the same way we are subject to the laws of physics, so, too, are we governed by other natural laws.

Just as removing predators from a population of deer will allow their numbers to run amuck (temporarily), technology has allowed us to greatly exceed the normal carrying capacity for our species.

Sadly, we are acting just like deer would: with no foresight nor apparent awareness of the consequences. The crash, when it comes, will be brutal, I am afraid. But, all-in-all, probably not entirely a bad thing.

Bernard, Croydon, UK

Well well, looks like good ol' Malthus was onto something after all...

Seb, London,

Population is clearly not the issue - it shows comparatively one of the smallest increases. The real target should be our consumption and our unfettered consumerist tastes.

Ted, Rome,

Sorry but I am not impressed by these rather vague and questionable statistics, none of which include any error margin on the figures; which used to be a basic requirement of any professionally produced statistic.

When I go out and look around me I see a green flourishing landscape with clear air and sky, and yes I do live adjacent to a city in a technologically advance country.

Wini, South Coast, UK

Immigration from 3rd world to first world that increases first world population. 3rd world population bubble is destroying rainforests and wild life habitats. Let's not forget the hard to understand censoring of comments at Times on Line.

Old Atlantic, Atlantic City, NJ

Free-enterprise CAPITALISM, is THE problem!. Instead of living sustainably, we are living like gluttons - using up the planets natural resources - and are paying the price. Democratic governments support CAPITALISM, allowing anyone to degrade the planet for proft. What shall it profit us if we coninue to live like this? Free-market capitalism must become in harmony with a sustainably clean planet.

Michael, Birmingham, England

"Population - 34 per cent higher than 20 years ago - Could reach 9.7 billion by 2050 "

In reply we would suggest that the population increase will not happen as the parasite Homo Sapiens will activate one of its most powerful evolutionary tactics, and will intelligently adapt; via collective intelligence. Remember that most parasites do not harm their host, and many actually are of benefit... as in a symbiotic relationship.

Humans do not have to harm the earth, they can protect and benefit it. China has already instigated a birth control program, and India is following.

Wini, South Coast, UK

Maybe it's time for the Catholic Church to change its stance on contraception - that could contribute significantly to reducing overpopulation on the planet.

Alex, Georgetown, Grand Cayman, Cayman Islands

Good news for animals.

Subramaniam, Paris,

The politicians of the world cannot point to the basic problem. The unspeakable word is population. It is bleakly obvious that the planet cannot feed the vast mass of humans who live on it. We are having to strip the earth's crust of all its nutrients and burn and pollute the atmosphere at a rate that cannot be sustained for more than a generation. Yet no one speaks out on this.
We should have had the dignity and sense to limit our reproduction somewhere like 50 years ago. But our numbers are increasing now probably faster than ever before. More alarmingly, we're all getting greedier, and we want more cars, more food and a bigger share of a rapidly shrinking planet. One wonders how long it will be before the media starts to serious discuss these bleak facts.

Richard Spivack, London, United Kingdom

Too many people equals increases in: consumption, polution,conflict,inequality etc etc, Oh yes and maybe Global Warming.
Fewer feet equals smaller 'footprint'.

David, Nassau, Bahamas

The population must be the target. This is the real threat to the planet, not C02.
As for the loss of languages this is not a problem more a bonus.

David Thijm, Stourbridge, UK

Thank goodness the UN spent time putting this list together, it keeps them doing anything that might actually help someone.

Victor, Portland, USA