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It reads something like this: In order to find a population that I was fairly confident met my definition of sustainability, I had to look well back in history - in fact back into Paleolithic times.

The sustainability conditions I chose were: I also assumed the populace would each use about as much energy as a typical hunter-gatherer: There are about million square kilometers, or 60 million square miles of land on Planet Earth.

However, two thirds of that area is covered by snow, mountains or deserts, or has little or no topsoil. This leaves about 50 million square kilometers 20 million square miles that is habitable by humans without high levels of technology.

A typical population density for a non-energy-assisted society of hunter-forager-gardeners is between 1 person per square mile and 1 person per square kilometer. Because humans living this way had settled the entire planet by the time agriculture was invented 10, years ago, this number pegs a reasonable upper boundary for a sustainable world population in the range of 20 to 50 million people.

I settled on the average of these two numbers, 35 million people. That was because it matches known hunter-forager population densities, and because those densities were maintained with virtually zero population growth less than 0. If we were to spread our current population of 7 billion evenly over 50 million square kilometers, we would have an average density of per square kilometer.

Based just on that number, and without even considering our modern energy-driven activities, our current population is at least times too big to be sustainable. As I said above, we also need to take the population's standard of living into account. Our use of technological energy gives each of us the average planetary impact of about 20 hunter-foragers.

What would the sustainable population be if each person kept their current lifestyle, which is given as an average current Thermodynamic Footprint TF of 20? We decided above that the maximum hunter-forager population we could accept as sustainable would be 35 million people, each with a Thermodynamic Footprint of 1. First, we set I the allowable total impact for our sustainable population to 35, representing those 35 million hunter-foragers.

Next, we set AT to be the TF representing the desired average lifestyle for our population. In this case that number is We can now solve the equation for P. This number tells us that if we want to keep the average level of per-capita consumption we enjoy in in today's world, we would enter an overshoot situation above a global population of about 1. By this measure our current population of 7 billion is about 4, times too big and active for long-term sustainability.

For the sake of comparison, it is estimated that the historical world population just after the dawn of agriculture in 8, BC was about five million, and in Year 1 was about million. We crossed the upper threshold of planetary sustainability in about BC, and have been in deepening overshoot for the last 4, years. The Ecological Assessments As a species, human beings share much in common with other large mammals. We breathe, eat, move around to find food and mates, socialize, reproduce and die like all other mammalian species.

Our intellect and culture, those qualities that make us uniquely human, are recent additions to our essential primate nature, at least in evolutionary terms.

Consequently it makes sense to compare our species' performance to that of other, similar species - species that we know for sure are sustainable.

I was fortunate to find the work of American marine biologist Dr. Fowler, who has a deep interest in sustainability and the ecological conundrum posed by human beings. The following three assessments are drawn from Dr. First assessment In , Dr. Fowler and Larry Hobbs co-wrote a paper titled, "Is humanity sustainable?

In it, they compared a variety of ecological measures across 31 species including humans. The measures included biomass consumption, energy consumption, CO2 production, geographical range size, and population size. When it came to population size, Fowler and Hobbs found that there are over two orders of magnitude more humans than one would expect based on a comparison to other species - times more, in fact. Similarly, our CO2 emissions outdid other species by a factor of Based on this research, Dr.

Fowler concluded that there are about times too many humans on the planet. This brings up an estimate for a sustainable population of 35 million people. This is the same as the upper bound established above by examining hunter-gatherer population densities. Second assessment In , five years after the publication cited above, Dr. Fowler wrote another paper entitled "Maximizing biodiversity, information and sustainability.

In other words, what is the largest human population that would not reduce planetary biodiversity? This is, of course, a very stringent test, and one that we probably failed early in our history by extirpating mega-fauna in the wake of our migrations across a number of continents.

In this paper, Dr. Fowler compared 96 different species, and again analyzed them in terms of population, CO2 emissions and consumption patterns. This time, when the strict test of biodiversity retention was applied, the results were truly shocking, even to me.

According to this measure, humans have overpopulated the Earth by almost times. In order to preserve maximum biodiversity on Earth, the human population may be no more than 10 million people - each with the consumption of a Paleolithic hunter-forager. Third assessment After this article was initially written, Dr. Fowler forwarded me a copy of an appendix to his book, "Systemic Management: In it he describes yet one more technique for comparing humans with other mammalian species, this time in terms of observed population densities, total population sizes and ranges.

After carefully comparing us to various species of both herbivores and carnivores of similar body size, he draws this devastating conclusion: It puts a sustainable human population at about 7 million.

Conclusions As you can see, the estimates for a sustainable human population vary widely - by a factor of from the highest to the lowest. The Ecological Footprint doesn't really seem intended as a measure of sustainability. Its main value is to give people with no exposure to ecology some sense that we are indeed over-exploiting our planet.

It also has the psychological advantage of feeling achievable with just a little work. As a measure of sustainability, it is not helpful.

As I said above, the number suggested by the Thermodynamic Footprint or Fossil Fuel analysis isn't very helpful either - even a population of one billion people without fossil fuels had already gone into overshoot.

That leaves us with four estimates: The central number of 35 million people is confirmed by two analyses using different data and assumptions. My conclusion is that this is probably the absolutely largest human population that could be considered sustainable.

The realistic but similarly unachievable number is probably more in line with the bottom two estimates, somewhere below 10 million. I think the lowest two estimates Fowler , and Fowler are as unrealistically high as all the others in this case, primarily because human intelligence and problem-solving ability makes our destructive impact on biodiversity a foregone conclusion.

After all, we drove other species to extinction 40, years ago, when our total population was estimated to be under 1 million. So, what can we do with this information? It's obvious that we will not and probably cannot voluntarily reduce our population by Even an involuntary reduction of this magnitude would involve enormous suffering and a very uncertain outcome. It's close enough to zero that if Mother Nature blinked, we'd be gone. In fact, the analysis suggests that Homo sapiens is an inherently unsustainable species.

This outcome seems virtually guaranteed by our neocortex, by the very intelligence that has enabled our rise to unprecedented dominance over our planet's biosphere. Is intelligence an evolutionary blind alley? From the singular perspective of our own species, it quite probably is. If we are to find some greater meaning or deeper future for intelligence in the universe, we may be forced to look beyond ourselves and adopt a cosmic, rather than a human, perspective.

Discussion How do we get out of this jam? How might we get from where we are today to a sustainable world population of 35 million or so? We should probably discard the notion of "managing" such a population decline. People seem virtually incapable of taking these kinds of decisions in large social groups. We can decide to stop reproducing, but only as individuals or perhaps small groups. Without the essential broad social support, such personal choices will make precious little difference to the final outcome.

Politicians will by and large not even propose an idea like "managed population decline" - not if they want to gain or remain in power, at any rate. China's brave experiment with one-child families notwithstanding, any global population decline will be purely involuntary.

A world population decline would will be triggered and fed by our civilization's encounter with limits. These limits may show up in any area: In , shortly after I grasped the concept and implications of Peak Oil, I wrote my first web article on population decline: The Elephant in the Room. In it I sketched out the picture of a monolithic population collapse: As time has passed I've become less confident in this particular dystopian vision.

It now seems to me that human beings may be just a bit tougher than that. We would fight like demons to stop the slide, though we would potentially do a lot more damage to the environment in the process. We would try with all our might to cling to civilization and rebuild our former glory. Different physical, environmental and social situations around the world would result in a great diversity in regional outcomes. To put it plainly, a simple "slide to oblivion" is not in the cards for any species that could recover from the giant Toba volcanic eruption in just 75, years.

Still, there are those physical limits I mentioned above. They are looming ever closer, and it seems a foregone conclusion that we will begin to encounter them for real within the next decade or two. In order to draw a slightly more realistic picture of what might happen at that point, I created the following thought experiment on involuntary population decline.

It's based on the idea that our population will not simply crash, but will oscillate tumble down a series of stair-steps: I started the scenario with a world population of 8 billion people in I assumed each full cycle of decline and partial recovery would take six generations, or years.

It would take three generations years to complete each decline and then three more in recovery, for a total cycle time of years. In ten full cycles - 2, years - we would be back to a sustainable population of about million. The biggest drop would be in the first years, from to when we would lose a net 53 million people per year. Even that is only a loss of 0. As a scenario it seems a lot more likely than a single monolithic crash from here to under a billion people.

Here's what it looks like: It's important to remember that this scenario is not a prediction. It's an attempt to portray a potential path down the population hill that seems a bit more probable than a simple, "Crash! With climate change getting ready to push humanity down the stairs, and the strong possibility that the overall global temperature will rise by 5 or 6 degrees Celsius even before the end of that first decline cycle, our prospects do not look even this "good" from where I stand.

Rest assured, I'm not trying to present 35 million people as some kind of "population target". It's just part of my attempt to frame what we're doing to the planet, in terms of what some of us see as the planetary ecosphere's level of tolerance for our abuse.

The other potential implicit in this analysis is that if we did drop from 8 to under 1 billion, we could then enter a population free-fall. As a result, we might keep falling until we hit the bottom of Olduvai Gorge again.

My numbers are an attempt to define how many people might stagger away from such a crash landing. Some people seem to believe that such an event could be manageable.

I don't share that belief for a moment. These calculations are my way of getting that message out. I figure if I'm going to draw a line in the sand, I'm going to do it on behalf of all life, not just our way of life.

What can we do? To be absolutely clear, after ten years of investigating what I affectionately call "The Global Clusterfuck", I do not think it can be prevented, mitigated or managed in any way.

If and when it happens, it will follow its own dynamic, and the force of events could easily make the Japanese and Andaman tsunamis seem like pleasant days at the beach. The most effective preparations that we can make will all be done by individuals and small groups. It will be up to each of us to decide what our skills, resources and motivations call us to do. It will be different for each of us - even for people in the same neighborhood, let alone people on opposite sides of the world.

I've been saying for a couple of years that each of us will each do whatever we think is appropriate to the circumstances, in whatever part of the world we can influence.

The outcome of our actions is ultimately unforeseeable, because it depends on how the efforts of all 7 billion of us converge, co-operate and compete. The end result will be quite different from place to place - climate change impacts will vary, resources vary, social structures vary, values and belief systems are different all over the world. The best we can do is to do our best.

Here is my advice: Stay awake to what's happening around us. Don't get hung up by other people's "shoulds and shouldn'ts". Occasionally re-examine our personal values. If they aren't in alignment with what we think the world needs, change them. Others are as much victims of the times as we are - even the CEOs and politicians. Blame, anger and outrage is pointless. It wastes precious energy that we will need for more useful work. Laugh a lot, at everything - including ourselves.

Hold all the world's various beliefs and "isms" lightly, including our own. Love everything just as deeply as you can. That's what I think might be helpful. If we get all that personal stuff right, then doing the physical stuff about food, water, housing,transportation, energy, politics and the rest of it will come easy - or at least a bit easier. And we will have a lot more fun doing it. I wish you all the best of luck! Global population is as of now projected to reach 9. These staggering levels of growth in humans leads to the question of whether the resources of our ecosystems are enough.

British journalist Vivien Cummings analyzes how many people can live on Earth without depleting the planet. The first half of the article pushes for the notion that consumption levels are the key, not population by itself.

The Western World has for example a much higher emission of CO2 per capita than poorer nations. If countries with excessive population growth levels could be swayed to keep their "footprints" small, we could sustain a large number of people in the world.

But experience and history shows that they will seek more material goods as they become more affluent. Especially people living in the cities will you see strong effects like pollution, emissions, smog and similar as they experience urban population growth. Also wealthier countries have the greatest footprint per household. Will Steffen from the Australian National University suggests that, if fertility rates were further reduced, the world could be stabilized at a number around 9 billion and then slowly fall, but this is very hard to achieve.

Corey Bradshaw of the University of Adelaide in Australia concluded in a study, that if two billion people died tomorrow - or if every government adopted controversial fertility policies such as China's one-child policy - there would still be as many if not more people on the planet by as there are today. The UNFPA calculates that million women in the poorest countries did not want their last child, but did not have the means to prevent the pregnancy.

If these women's needs were met, it would have a significant impact on global population trends. Creating a sustainable population is as much about boosting women's rights as it is about reducing consumption of resources. Cummings points out the responsibility incurred on Western nations to change their consumption patterns; in face of growing population numbers we can't expect to keep on our way of life.

Unless we slow the destruction of Earth's declining supply of plant life, civilization like it is now may become completely unsustainable, according to John Schramski, lead author of a study published by researchers at the University of Georgia's College of Engineering in the Proceedings of the National Academy of Sciences.

Large animals -- including elephants, rhinoceroses, polar bears and others -- face the highest rate of decline. After billions of years simple organisms evolved the ability to transform the sun's light into energy, eventually leading to an explosion of plant and animal life that bathed the planet with lush forests and extraordinarily diverse ecosystems. This stored energy is needed to maintain Earth's complex food webs and biogeochemical balances.

The study's calculations are grounded in the fundamental principles of thermodynamics, a branch of physics concerned with the relationship between heat and mechanical energy. Chemical energy is stored in plants, or biomass, which is used for food and fuel. If biomass drops below sustainable thresholds, the population will decline drastically, and people will be forced to return to life as hunter-gatherers or simple horticulturalists.

Thermodynamic laws are 'absolute and incontrovertible; we have a limited amount of biomass energy available on the planet, and once it's exhausted, there is absolutely nothing to replace it.

Virtually every country in the Mediterranean region consumes more ecological resources than local ecosystems can replenish. To cover the widening gap between supply and demand, the region is increasingly relying on global resources, which are also becoming increasingly limited. Nations in the region now need to factor in the resource constraints of their trade partners and recognize the risk it poses to their own economic prosperity.

The average Food Footprint of a Mediterranean resident is approximately 0. On a scale of zero to one, the U. Development Programme defines 0. Since , most of the Mediterranean countries have moved beyond that threshold. This composition poses a specific challenge because food consumption can only be shifted increased or decreased to a small extent, given that food is one of the key basic human needs. The reasons for the Mediterranean region's relatively high food Footprint include water scarcity, low agricultural productivity, growing dependence on imported food, and a transition away from the traditional environmentally friendly and healthy Mediterranean diet.

Instead of consuming cereals, vegetables and oil typical of the Mediterranean diet-which have a low Footprint-countries are consuming more meat and dairy, which have higher Footprints. In this newly released interview, Rex Weyler shares his observations of "what can happen as a civilization grows out of control.

Weyler does express some hope for the future, as well, and outlines changes needed to bring human civilization back to living within ecological limits. This is the ninth in our series of podcasts and radio programs. We post a new podcast episode every Thursday. Click here to play this audio interview. Instead of problems in the subprime housing market, as economists claim, the Great Recession was a resource depletion problem masquerading as a financial crisis.

The depleted resource was oil: Many chose to put food on the table and gas in their tanks instead of paying their too-large mortgages.

The world's economic and environmental fates have become forever interconnected. Natural resources are not unlimited, We can clear-cut only so many forests, pump only so much oil out of the ground and drain only so much water out of aquifers before our behavior becomes unsustainable.

GDP - or gross domestic product - measures a nation's flow of income, but it's a flawed yardstick and leads to some perverse accounting. For example, GDP grew when agricultural runoff caused toxic algal blooms in Lake Erie last year due to spending on bottled water and the goods and services needed to repair the damage.

This would suggest that polluting one of our Great Lakes benefits our economic health. When we become singularly focused on growing GDP, we're left with no incentive to sustainably manage our natural resources. We need to look to the future beyond short-term growth. What we use today is gone forever, making the problem worse and leaving it for our children to solve.

In the author's new book "Beyond GDP: National Accounting in the Age of Resource Depletion," we need to stop thinking of the economy as an "engine" that can stall, and start thinking of it as a metabolism or an organism that does not consume more energy than it acquires.

Using the metabolism metaphor, we ought to develop a new system of national accounting that includes raw materials flowing into the economy, burning of fossil fuels for energy and disposal of waste wherever possible.

In the early s, the U. Congress expressly forbade the collection of such data in Meanwhile, the Organisation for Economic Co-operation and Development and even emerging economies have moved ahead without the United States.

Economic-environment accounts are now common outside U. The Bureau of Economic Analysis ought to seek authorization to restart its program. If we as a society can begin collecting relevant data, perhaps we can begin to use the analytical tools, metrics and knowledge to go beyond GDP and make wise choices for the future.

Our deepest hope is to make a positive contribution in that direction. In Nigeria, the chairman of the National Population Commission, NPC, Eze Duruiheoma, warned that the country's economy was incapable of supporting the nation's population annual exponential growth rate of 3. The current challenges such as militancy in the Niger Delta, Boko Haram, conflicts between farmers, and other security implications were manifestations of Nigeria's population, he said.

He said the youth population poses security challenges of unemployment, social vices and the breakdown of family values. Additional challenges are rural-urban migration, declining availability of arable land, and decay in social infrastructure.

According to a report by the Global Footprint Network, the population of the United States is using twice the renewable natural resources and services that can be regenerated within its borders. Alaska, Texas, and Michigan are the most resource-abundant states based on biocapacity, a measure of bioproductive land. California, Texas, and Florida have the highest ecological deficits -- when demand for resources exceeds what nature can regenerate biocapacity within the state borders.

An ecological deficit is possible because states can import goods, overuse their resources for instance by overfishing and overharvesting forests , and emit more carbon dioxide into the atmosphere than can be absorbed by their own forests. But doing so requires decision-makers to make strategic investments in infrastructure and our natural capital and set policies aimed at conserving our planet's resources.

In the book Limits to Growth, commissioned by a think tank called the Club of Rome, predicted the collapse of our civilization some time this century. Research from the University of Melbourne has found the book's forecasts to be accurate, which, if things continue to follow the books track, we can expect the early stages of global collapse to start appearing soon.

Researchers working out of the Massachusetts Institute of Technology, including husband-and-wife team Donella and Dennis Meadows, built a computer model to track the world's economy and environment. Called World3, this computer model was cutting edge.

Industrialization, population, food, resource depletion, and pollution were tracked. If humanity followed the "business-as-usual" scenario, failing to take serious action on environmental and resource issues, the model predicted "overshoot and collapse" - in the economy, environment and population.

Click on the headline above to see the graphs which show that, up to , the data is strikingly similar to the book's forecasts. The graphs show that resources are being used up at a rapid rate, pollution is rising, industrial output and food per capita is rising. The population is rising quickly. To feed the continued growth in industrial output there must be ever-increasing use of resources. But resources become more expensive to obtain as they are used up.

As more and more capital goes towards resource extraction, industrial output per capita starts to fall - in the book, from about As pollution mounts and industrial input into agriculture falls, food production per capita falls. Health and education services are cut back, and that combines to bring about a rise in the death rate from about Global population begins to fall from about , by about half a billion people per decade.

Living conditions fall to levels similar to the early s. The Global Financial Crisis of and ongoing economic malaise may be a harbinger of the fallout from resource constraints. The pursuit of material wealth contributed to unsustainable levels of debt, with suddenly higher prices for food and oil contributing to defaults.

Peak oil could be the catalyst for global collapse. Even the conservative International Energy Agency has warned about peak oil. If these resources soak up too much capital to extract, the fallout would be widespread. The University of Melbourne research has not found proof of collapse as of But in Limits to Growth those effects only start to bite around Things could change the future: But it seems unlikely that the quest for ever-increasing growth can continue unchecked to without causing serious negative effects.

It may be too late to convince the world's politicians and wealthy elites to chart a different course. So to the rest of us, maybe it's time to think about how we protect ourselves as we head into an uncertain future.

August 19th was Earth Overshoot Day. It is the approximate date that humanity's annual demand on nature exceeds what the Earth can renew this year. In less than 8 months, we have demanded an amount of ecological resources and services equivalent to what Earth can regenerate for all of Ecological deficit spending is made possible by depleting stocks of fish, trees and other resources, and accumulating waste such as carbon dioxide in the atmosphere and oceans.

It would take more than 1. It is possible to turn the tide. Global Footprint Network and its partners are supporting governments, financial institutions, and other organizations around the globe in making decisions aligned with ecological reality. See how many Chinas it takes to support China. How many United States to support the United States, etc. California's, population grew by more than 4. The addition of 2,, immigrants between and represents The primary consumer of water in California is agriculture and industry.

Much agricultural water is wasted. Higher prices encourage investments in irrigation systems and a change in crop selection. Farmers use more water than they would if market forces were allowed to guide the use of water. On a national level, we are using LESS water today than we did 20 years ago. While the population of the U. Even a slight increase in the price of water or energy results in pressure to conserve water.

The primary consumers are irrigation and industry, both have curtailed their water usage. Increased consumption is evident in the public supply and livestock. Population growth across the nation needs to be brought under control. Arizona's population growth rate compares to Pakistan, Tanzania, and Honduras while Colorado's is similar to that of Ghana, El Salvador, and the Philippines. Many of the scientists and speakers said Meadows was right about Limits to Growth in their presentations -- indeed, his model appeared to be ahead of schedule.

Meadows hates to give dates, but when pressed, did say that although he thought the most likely time-frame for collapse back in based on various model projections, the exponential use of resources and population growth appeared to have moved the time-frame forward to around At the "Limits to Growth" conference in he said the time-frame appears to be Dennis Meadows is a co-author of The Limits to Growth.

In , the team of 66 scientists he assembled for the original Limits to Growth study concluded the most probable result will be a rather sudden and uncontrollable decline in both population and industrial capacity. He has retired from Club of Rome discussions, and has found more cheerful uses for his time.

But he seemed happy with the outcome, saying that this is the first time he faced an audience that did not need convincing. Instead, he took the time to add some details that I think are crucially important, among them the fact that his WORLD3 model is only accurate until the peaks are reached.

Once the peaks occur between and all bets are off: It's because people don't care about climate change. Despite myriad conferences and commissions on sustainable development since then, the world opted for overshoot. The two-leggeds hairless apes did what they always have done. They dominated and subdued Earth. Faced with unequivocable evidence of an approaching existential threat, they equivocated and then attempted to muddle through. Global civilization will only be the first of many casualties of the climate the Mother Nature now has coming our way at a rate of change exceeding any comparable shift in the past 3 million years, save perhaps the meteors or supervolcanoes that scattered our ancestors into barely enough breeding pairs to be able to revive.

This change will be longer lived and more profound than many of those phenomena. We have fundamentally altered the nitrogen, carbon and potassium cycles of the planet. It may never go back to an ecosystem in which bipedal mammals with bicameral brains were possible. Or, not for millions of years". Last, senior writer at The Weekly Standard, insists that America is heading over a demographic cliff because we're not making enough babies. We added more than million in the last 40 years, and in the next 40 to 50 years, according to the U.

Census Bureau, we will add another million, most of it directly and indirectly from immigration. Our current population of million runs a substantial ecological deficit that is pushing us ever deeper into ecological debt, according to the Global Footprint Network, which says: But we only have one planet at our disposal.

Part of caring for our planet is having the collective wisdom to live within limits, including limiting the size of our families and population. We are busily sawing off the limb upon which the entire human enterprise rests-degrading and squandering the "natural capital" that makes sustainable economic prosperity possible.

Last quotes Julian Simon who said that " Human ingenuity, it turns out, is the most precious resource. Commodity prices did fall from to , but in the s prices for almost all raw materials have increased sharply. Americans mistook temporary abundance of nonrenewable natural resources like the fossil fuels and metals as permanent sufficiency. It's a miscalculation with monumental consequences. We have fewer wetlands, fewer free-flowing rivers, less available surface and groundwater, less open space, fewer remaining fossil fuels and high grade metal and mineral ores, fewer arable soils, fewer healthy and more diseased forests, more wildfires and droughts, record temperatures, fewer fish, less de facto wilderness, more threatened and endangered species, more harmful invasive species, higher carbon dioxide emissions, and more crowded parks and beaches than ever before.

The climate is becoming more erratic; sea level is rising, and the oceans are becoming more polluted and acidic. Julian Simon once bragged: Physicist Al Bartlett calculated that after just 17, years only 0. However, more seniors living longer lives has also added to our population. Furthermore, Americans can do the world a big favor by consuming less. Before making the policy of precaution, categorical evidence is needed.

When the potential menace of "activities" is regarded as a critical and "irreversible" endangerment, these "activities" should be forbidden. For example, since explosives and toxicants will have serious consequences to endanger human and natural environment, the South Africa Marine Living Resources Act promulgated a series of policies on completely forbidding to "catch fish" by using explosives and toxicants.

According to Cooney, there are 4 methods to manage the precaution of biodiversity in natural resources management;.

In order to have a sustainable environment, understanding and using appropriate management strategies is important. In terms of understanding, Young [50] emphasises some important points of land management:. The ecological principles relate to time, place, species, disturbance and the landscape and they interact in many ways. It is suggested that land managers could follow these guidelines:.

From Wikipedia, the free encyclopedia. This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. June Learn how and when to remove this template message. Agriculture Agroecology Biodiversity Bioregion Conservation biology Conservation ethic Conservation movement Conservation reliant species Deep ecology Earth Science Ecology Ecology movement Ecosystem Environmental movement Environmental organizations Environmental protection Environmental resources management Forestry Global warming Green party Green politics Habitat conservation Holistic management List of environmental issues List of environmental organizations Natural capital Natural environment Natural resource Nature Progressivism Recycling Renewable energy Renewable resource Stewardship Sustainable agriculture Sustainable management.

Archived from the original PDF on 8 February Retrieved 27 October Topics in the History of Natural Resource Management: Academy of Management Review. Working Paper, University of Toronto, pp.

Sustainability Research Institute, University of Leeds, pp. Institutional incentives and sustainable development: Society and Natural Resources, Community natural resource management: Histories and politics of community-based natural resource management. Community-based Natural Resource Management in Botswana. The Geographical Journal, Vol , No. Devolution and community-based natural resource management: Proceedings of the National Academy of Sciences.

Assessing the need to manage conflict in community-based natural resource projects PDF. Archived from the original on 28 September Archived from the original PDF on 17 February The diffusion of innovative biodiversity conservation policies and practices". The Journal of Wildlife Management.

The question of scale in integrated natural resource management. Conservation Ecology 5 2: Archived from the original PDF on 21 June Biology Chemistry green Ecological economics Environmental design Environmental economics Environmental engineering Environmental health epidemiology Environmental studies Environmental toxicology Geodesy Physics Sustainability science Systems ecology Urban ecology. Energy conservation Environmental technology Natural resource management Pollution control Recycling Remediation Renewable energy Road ecology Sewage treatment Urban metabolism Water purification Waste management.

Human impact on the environment Sustainability. Ecological anthropology Ecological economics Environmental anthropology Environmental economics Environmental communication Environmental history Environmental politics Environmental psychology Environmental sociology Human ecology Human geography Political ecology Regional science. It provides easy-to-use access to various open tenders.

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