Population Matters

Environment & resources

Environment & resources


Humanity relies on ecosystems and biodiversity for its well-being in many acknowledged and some unacknowledged ways. Yet we are systematically reducing the quantity and variety of the natural world through development, pollution — including climate change — and resource exploitation. We must preserve nature through limiting our consumption and population to sustainable levels.

We rely on the world’s ecosystems and rich biodiversity for everything we need to exist, from the regulation of our atmosphere and the pollination of plants to the creation of important new medicines and crops.


The value of biodiversity lies in both the range of species and the genetic differences within species.

We are reducing this crucial diversity through development, exploitation and pollution; our numbers and activity increasingly encroach on the natural world. Our impact on biodiversity takes many forms, and population growth significantly contributes to virtually all of them.

Climate change, itself arguably caused by human activity, particularly in the industrialized world, is also playing a part in the rapid decline of global biodiversity.

We are putting already limited space and amenities under yet more pressure.

In summary, the more of us there are, the greater is our impact on the environment.


The enormous population growth of the last two hundred years has been based on humanity’s success in exploiting resources and using them to increase the production of food and other goods. Yet extraction costs are rising as more accessible reserves are exhausted, and climate change may mean that some resources cannot be used safely.

Historical usage

Historically the size of human communities has depended on their ability to harness resources. Population growth was relatively slow until the 18th century, when a step-change in agricultural productivity helped world population to rise dramatically.

Factory workers

The industrial revolution initiated a huge increase in global trade while public health improved tremendously — both changes enabled population to increase.

In the 20th century, increased agricultural productivity achieved through the Green Revolution allowed population numbers to double between 1950 and 1990. Nevertheless, our dependence on natural resources remains absolute. Numbers are now projected to rise from seven billion today to between eight and eleven billion by 2050. It is unlikely that an equivalent increase in food production can be repeated without the use of significantly more energy, water and fertiliser, inputs which are themselves limited and may also be vulnerable to climate change.


Industrialisation and rising standards of living are also increasing each person’s consumption of water, energy and materials as well as food. Our lifestyles and the technology we use are driving overconsumption, leading to serious consequences as resources run low.

In the short term, living standards are affected adversely by rising prices for resources of all kinds. In the longer term, resources may be increasingly unaffordable for some individuals who previously had a good standard of living.

Read more about the earth’s carrying capacity, biocapacity and humanity’s ecological footprint.

Next: Biodiversity