5 ways that humans impact ecosystems

Excluding the beaver, no other animal on the planet alters its environment as much as humans. As a result, the impact of the actions of humans is widespread even if the effects are not overtly noticeable. Some ways that we affect our ecosystems include:

  • Habitat Fragmentation: This occurs when an organism’s favored environment is disrupted and made discontinuous. This, in turn, separates the population which can result in decreased genetic variability and overall population numbers if the male:female sex ratio is disproportionate.
  • Land-Use Changes: This is the changing of the Earth by humans to harvest resources and re-purpose the area.
  • Habitat Destruction: The removal of resources and changes to the land causing it no longer capable of sustaining the ecological communities that naturally occur in a given space. This often results in the loss of biodiversity and sometimes species extinction.
  • The Introduction of Non-Native species: Occurs due to travel [individual or economically motivated]. These species often have no natural predators in a new system, so they are more easily able to integrate themselves into a biological community.  This often results in the displacement of native species.
  • Pollution: The manipulation of resources, burning of fossil fuels, waste production, nutrient over-enrichment and the introduction of harmful chemicals results in changes in the environment making it inhospitable to the natural inhabitants.

Ellis, E. (2013). Land-use and land-cover change. Retrieved from http://www.eoearth.org/view/article/154143

an introduction to integrated pest management (IPM)

Integrated pest management (IPM) is a long-term pest prevention program that focuses on ecosystem-based strategies for the control of pest related issues. This is accomplished through a combination of techniques including biological control, habitat manipulation, modification of cultural practices and the use of resistant cultivars. The use of chemical pesticides is then restricted to applications only after strict monitoring that is based on established guidelines indicates that stronger measures are required for pest management. In the event that chemical agents are required, they are applied in a targeted manner intended to minimize risks to the environment, other organisms (especially beneficial and non-target organisms) and to human health.

The 8 principles of IPM are as followed:

  1. In an effort to prevent and/or combat pests, the following intelligent production practices shall be used: crop rotation, sustainable cultivation techniques, resistant/tolerant cultivars and certified seed production systems, balanced fertilization, irrigation and drainage techniques, proper hygiene measures and the protection and proliferation of beneficial organism.
  2. The use of biological, physical and non-chemical control methods must be preferred to chemical options as long as the non-chemical options provide acceptable pest control.
  3. In the event that pesticides must be applied, they shall be target-specific and strategically applied in an effort to reduce negative health outcomes.
  4. Pesticides shall be used only on an as-needed basis and the frequency and intensity of use  should be minimized in order to reduce the risk of resistance populations.
  5. In cases where pest resistance has been established and repeat pesticide application is necessary, anti-resistance strategies should be integrated into control efforts.  
  6. Record keeping is essential and should be based on detailed records in order to determine the efficacy of pest control programs – especially in the case of chemical inputs.
  7. Monitoring efforts are essential in order to track pest presence.  This can be accomplished via observations, forecasting and early diagnosis systems and information, as well as information from professionally qualified .  
  8. The information garnered by monitoring efforts shall be used to determine when and which plant protection measures will be taken.  There should be scientifically supported threshold values upon which to base decision making.  Said values should be adapted to local conditions including climate, crop type and topographical qualities.





the greenhouse effect

The term greenhouse effect has some pretty negative connotations.  On the one side, there are those who hate all the tree-hugging hippies who are against progress and technology, and think that global warming is a giant scam developed by Al Gore in order to ruin the United States’ economy and turn the country into a communist paradise.  On the other side, there are those that think that the evil meat-eating fascists are trying to destroy the planet and the only way to stop them is by buying all the coolest, newest, greenest, most environmentally-friendly items.

Photo Credit: wunderground.com

However, truth be told, if it were not for greenhouse gases trapping heat in the atmosphere, the world would be a very cold place.  In fact, greenhouse gases are what keeps the earth warm through a process called the greenhouse effect.

The earth gets energy from the sun in the form of sunlight.  The earth’s surface absorbs some of this energy and heats up.  This is why the surface of a road can feel hot even after the sun has gone down.  The earth cools down by giving off a different form of energy called infrared radiation.  Before this radiation can escape to outer space, greenhouse gases in the atmosphere absorb some of it, which in turn makes the atmosphere warmer.

However, it does not have to be quite so warm here on planet earth and it is best to mitigate the environmental effects of human activities when possible.  In order to do this, the discussion needs to shift to other types of greenhouse gases because CO2 is relatively harmless when compared with many others.  Furthermore, CO2 gases can be dramatically reduced simply by planting a whole lot more plants and not destroying the ones that already exist and/or ending the world’s love affair with fossil fuels.

Greenhouse Gas Production by Sector             Photo Credit: epa.gov

A few of the other types of much more concerning greenhouse gases include:

  1. Methane: produced via:
  • livestock production – sheep and cows produce methane as a byproduct of their digestion process and methane as released as manure decomposes
  • trash decomposition in landfills
  • sourcing and transport of natural gas – natural gas is mostly methane and can easily leak through pipes
  • coal mining – pockets of methane are released as the earth is mined

Methane stays in the atmosphere for 12 years and traps 20 times more heat than CO2.

2. Nitrous Oxide: produced via:

  • farming – the introduction of synthetic nitrogen which is oxidised by plants
  • the burning of fossil fuels
  • some manufacturing and industrial processes

Nitrous oxide stays in the atmosphere for 114 years and traps 298 times more heat than CO2.

3. Fluorinated gases: produced via:

  • leaking coolants – produced by certain devices, such as refrigerators and air conditioners
  • manufacturing and industry – computer chip production is a major contributor

The length of time that these gases stay in the atmosphere varies, but ranges from several to thousands of years.  The heat-trapping properties also vary but range from a few hundred to 23,000 times that of CO2.  It is expected that fluorinated gas production will increase dramatically faster than any other greenhouse gases.

So, the greenhouse effect is a cause for concern, but it also a fundamental component of our existence.  As such, it is best when we stop focusing on how to stop this process and start focusing on how we as humans can make more conscientious decisions in order to preserve this special place we live and let mother nature do her job.

eutrophication, choking the life out of a body of water near you?

Eutrophication is a process caused by excess phosphates and nitrogen which creates algae blooms. Fast-growing algae die each year and sink to the bottom of the floor of a given body of water. Here it turns into an incredibly rich mud where bacterial decayers thrive. Due to their unnatural quantities and massive appetites, the oxygen in the water is too rapidly consumed which effectively kills the other living organisms in the water and creates an inhospitable environment for potential inhabitants. This process results in the premature death of a body of water [a process that normally takes 150 years can occur within approximately a year].  Locations that have become eutrophic are denoted as “dead zones”.


The majority of damage from eutrophication in the United States is caused runoff from lawn fertilizer, although commercial fertilizers contribute significantly to the problem.  In the United States, it is estimated that 70 million tons of pesticides, fertilizers, and herbicides are applied annually to lawns in the United States. This is 10 times the amount used by farmers. Other sources include runoff from cities, sewage and even N and P used inland that is transported by the wind to varying water sources.

To add insult to injury, according to the website beyondpesticides.org:

“Of the 30 commonly used lawn pesticides, 17 are linked with cancer or carcinogenicity, 11 are linked with birth defects, 19 with reproductive effects, 24 with liver or kidney damage, 14 with neurotoxicity and 18 with disruption of the endocrine (hormonal) system.  Of those same 30 lawn pesticides, 17 are detected in groundwater, 23 have the ability to leach into drinking water sources, 24 are toxic to fish and other aquatic organisms vital to our ecosystem, 11 are toxic to bees and 16 are toxic to birds.”


There are several potential solutions to the issue of eutrophication.

The easiest would be to stop applying chemical fertilizers to lawns. However, a well-groomed lawn is often considered a status symbol and point of pride for many. This suggests that the use of fertilizers will continue, possibly even increase.

In turn, a myriad of varying solutions is required.  These options include increasing the presence of riparian buffer zones, restoring wetlands, reducing the density of livestock, treating sewer water and water from urban run-off, reducing the amount of N and P produced by vehicles and power plants and improving the efficiency of fertilizer application with targeted applications.


Without action, coastal waters will become unsuitable for aquaculture production, tourist destinations will lose their appeal when people cannot swim, fish or boat, biodiversity will be further reduced and aquatic and coastal ecosystems will become dramatically altered which reduces their effectiveness as water purifiers and storm barriers.





an alternative to the GDP: the genuine progress indicator (GPI)

The Genuine Progress Indicator [GPI] is a GDP alternative that places value on the overall well-being of the world, rather than only the money we spend and goods we consume, by using 26 indicators to consolidate “critical economic, environmental, and social factors into a single framework in order to give a more accurate picture of the progress – and the setbacks – we have made.” This allows the clearly negative qualities associated with growth to be subtracted from the positive attributes. In turn, a clearer picture of the impacts of policy decisions made is developed providing an opportunity to cultivate a path towards a more sustainable future.

Of the 26 indicators used for computing the GPI, 7 are economic: personal consumption expenditures, income inequality, adjusted personal consumption, cost of consumer durables, adjusted personal consumption, value of consumer durables, cost of underemployment, and net capital investment; 9 are environmental: cost of water pollution, cost of air pollution, cost of noise pollution, loss of wetlands, loss of farmland, loss of primary forests and damage from logging roads, carbon emission damage, cost of ozone depletion, and depletion of natural resources; and 9 are social: value of housework and parenting, cost of family changes, cost of crime, cost of household pollution abatement, value of volunteer work, loss of leisure time, value of higher education, value of highways and streets, costs of commuting, and cost of automobile accidents.


question: what are the causes of air pollution in china? how serious is this problem, and how does it impact other countries?

There are a variety of reasons for air pollution in China. Demand for cheap goods throughout the world prompt huge manufacturing efforts that are poorly regulated. A lack of enforceable energy and environmental standards enable production systems to exploit resources with few or no repercussions. An expanding middle class is also contributing to the increases in demand for transportation and electricity. Both produce a significant amount of air pollution, especially since electricity supplies in China are primarily dependent on some of the dirtiest sources of energy like coal.

Such a problem is incredibly serious. Citizens are subjected to terrible environmental conditions that are likely to cause various health ailments. The pollution also travels to the United States which contributes to already poor environmental conditions. For example, in California residents are subjected to at least one additional day of air conditions that exceed the federal limits for air pollution because of the influx of nitrogen oxides and carbon monoxide emitted by China and on other days at least one-quarter of sulfate pollution on the west cause is a result of exported goods from China. China also produces black carbon which is a known cause of asthma, emphysema, heart and lung disease, and various cancers. This type of pollution is not removed from the environment with rain.

air pollution by concentrated animal feeding operations

The article Air Pollution by Concentrated Animal Feeding Operations by P. Patel and T.J. Centner is justification for the regulation of concentrated animal feeding operations (CAFOS). Reasons include the health and environmental implications of CAFOS, a current lack of regulation and measurable standards and the currently unsuccessful legislation and guidelines. Two major points of the article are that there are too many exceptions and the current efforts are not addressing the root cause of the problems.

Chemicals emitted byCAFOs include ammonia, hydrogen sulfide, particulate matter and other hazardous air pollutants. CAFOs are not required to report hazardous air pollutants and are exempt from the Clean Air Act and The Comprehensive Environmental Response Compensation and Liability Act (ERLA) and the federal Emergency Planning and Right to Know Act (EPCRA).

A serious limitation to regulation is the lack of clear definitions for the health effects of CAFOS, such as headaches, nausea, anger, depression and other psychological ailments. This also prevents the EPA from imposing the already subjective levies to many delinquents. Other problems include too many exemptions and a lack of legislation/efforts to address the cause of the issues.  Pork producers are identified as the biggest environmental offenders.

Patel, P., Centner, T. J. (2010) Air pollution by concentrated animal feeding operations. Desalination & Water Treatment. 19(1-3) 12-16.