Human impact

Given the scale of human activity, the impact on the ecosystem is now global in scope and takes many forms. The plight of the polar bears is but one of many environmental issues being raised in multiple and comprehensive reports into global warming. The general conclusion is that mankind is probably to blame for climate change, which will also lead to more droughts, torrential rains, shrinking Arctic ice and glaciers and rising sea levels over the coming centuries.

We have already touched upon how technology developments have transform the nature of human society throughout history, although the scale of this  particular aspect only really started to have a global impact as the industrial revolution progressed into the 20th century. While many will consider technology has improved the human condition, it has also led to widespread pollution as industry has attempted to exploit and control the resources of natural world in pursuit of economic growth. From the historical perspective, the first human impact on the environment was only in terms of basic  survival needs, e.g. food and water, which has now developed into today’s worldwide agriculture industry, dependent on mechanisation, irrigation, pesticides and most importantly energy.

Agricultural Industry

One of the most obvious impacts of agriculture, on an industrial scale, is deforestation in order to clear land for both animal pasture or crops. However, it has been estimated that ‘only’ 5% of deforestation has been for animal, another 19% linked to the timber industry, a surprising 22% linked to palm oil   plantations, while the remaining 54% can be attributed to what amounts to ‘ slash-and-burn’   farming clearances.

While it is difficult not to assume that this level of deforestation does not have some overall environmental cost to the ecosystem, as a whole, much of this cleared land has also increased the demand for fresh water and  the need for large-scale irrigation projects, which then create knock-on problems, e.g.

  • Depletion of underground aquifers
  • Increased soil salinity and build up of toxic salts.
  • Over-irrigation often leads to other forms of water pollution.
  • High water runoff can cause flooding and soil erosion.

However, adding to this toxic mix are ‘pollutants ’ in the form of a wide range of agricultural chemicals, which in many cases are over-used causing soil contamination and the pollution of groundwater . Additionally, pesticides that are considered vital for crop yields have been shown to leave trace residues in foods and proven toxic to bees with a corresponding reduction in the pollination of some crops.

Fishing Industry

Today, there is a recognised disconnect between how many fish are available to be caught and humanity’s desire to catch them as a vital food source. In 2006, the journal Science published a four-year study in which it predicted that, at projected rates, the world would run out of wild-caught seafood by 2048.

This decline was attributed to both overfishing and pollution plus ‘other environmental factors’ that affect the ocean’s ecosystem. As might be expected, such claims are often simply dismissed as being fundamentally flawed.

Other Environmental Factors

The term ‘other environmental factors’ used above might appear a bit nebulous given the gravity of some of the predictions. While the following summary will hardly be exhaustive, it may provide an outline of some of the factors that may become increasing detrimental to global food production. Clearly, we might introduce the issue of climate change  as being one potential danger to maintaining global food production.

For global warming  may not only change the temperature, but rainfall and glacial run-off, which may then collectively alter the biocapacity of planet Earth to produce enough food, not just for the human population, but the domesticated animals on which humanity also depends. Likewise, rising  levels of carbon dioxide could have unpredictable effects on crop yields. Of course, when viewing the Earth’s ecosystem in terms of its numerous feedback mechanisms, it might be realised that the huge expansion of the agricultural industry has itself been a source of climate change. For it has been showed that the scale of the agricultural industry now produces significant amounts of greenhouse gases, such as carbon dioxide and methane, plus by altering the Earth’s surface profile, it can also change amount of the heat and light absorbed.

So what else might need to be taken in consideration?

As summarised above, large-scale agriculture irrigation can change both the quantity and quality of soil and water. For example, many irrigation schemes draw water from  rivers, which can then dramatically change the downstream environment. When irrigation depends on extracting groundwater, the level of the water descends, which can result in the losted freshwater being replaced by salinated or polluted run-off water. However, it is technology that often helps aggravate all these problems through the use of high-powered water pumps, dams and pipelines, which has only helped to increased the depletion of fresh water resources, such as aquifers, lakes, and rivers. It has been estimated that humanity now acquires more than 50% of the planet’s fresh water for use in irrigation. The net result is putting severe pressure on the ecosystem, both local and global, plus contributing to the extinction of many aquatic species.

So is technology the solution or part of the problem?

It might be argued that if all the technology was switched off over night, the ‘bottom 10% of humanity’ might survive, while virtually all development countries would fall into chaos. While this might appear to support the previous over-consumption arguments, it hardly seem to  be a ‘preferred’ solution. For technology has come to underpin our modern world with myriads of computer systems, mechanised machinery and power plants. However, this said, it also has to be recognised that the industrialization of agriculture over the last 200 years has resulted in a massive loss of top soil, which has taken thousands of years to form. In the US, 90% of the cropland is losing topsoil at a rate faster than it can be created, while globally about 30% of arable land has been lost through erosion.

But will/can technology deliver sustainable energy?

While there is now much talk of green-sources of energy, the fact remains that most of today’s global energy supply is still dependent on fossil fuel resources, which contribute to global warming and climate change. In the short-term, effort is going into energy conservation, either by reduced consumption or efficiency gains in products and equipment requiring energy. While, in the context of this discussion, you might wish to believe that energy conservation is being pursued purely for the future welfare of the planet, in many cases, it is the pursuit of financial savings and increased profits that is providing the biggest motivation. Of course, this may be a little too cynical, as many are pursuing the goal of ‘sustainable energy’ that may meet the needs of the present without necessarily compromising the environment for future generations. Current lines of research include hydroelectricity, solar energy, wind energy, wave power, geothermal energy, bio-energy, and tidal power plus further energy efficiencies. However, we possibly need to temper this optimism with the next question:

How long before sustainable energy arrives?

A Forbes’ article has suggested that it might take 20-30 years to generate 70-80% of our energy in a sustainable manner, but possible 80 years to get the last 20-30%. However, this article is assuming a mixture of sources, e.g. solar panels, wind-turbines, fuel cells, bio-fuel, where the infrastructure is primarily being upgraded in developed countries. Of course, even upgrading the infrastructure of a national power distribution system, inclusive of the adoption of electric cars, will undoubtedly cost billions, if not trillions, such that we can only hope that investors and the economy will be able to fund such large-scale projects in the timeframe suggested. So, it would seem that the discussion of how humanity might impact the ecosystem can lead to a seemingly endless list of issues, e.g. resource mining, transport, roads, aviation, shipping and even wars. Therefore, ‘upgrading’ the world to support possibly 10 billion people by 2050, while also pursuing the goal of ecological sustainability as resources become increasingly scarce and more expensive to extract within a possibly weakening global economy and a backdrop of conflicting interests associated with today’s global demographics may prove to be more than a challenge.