Prepare: In this discussion post you will be considering the role of land degradation, desertification, and biodiversity loss in an ecosystem. Land degradation can be caused by extreme weather conditions such as drought and coastal surges. However, it is also caused by human activities that degrade the productivity of the soil and impact the production of ecosystem goods and services (Land degradation and desertification, n.d.).  In the past century, the growing pressures of agricultural and livestock production, urbanization, and deforestation have significantly contributed to land degradation and desertification (Land degradation and desertification, n.d.). As you are reading the reports and watching the movie take notes on how these social, economic, and policy factors contribute to land degradation and desertification.

Land degradation and desertification also impacts human health and well-being. The degradation of land puts considerable stress of food-producing systems which often leads to malnutrition. Water scarcity and air pollutants are also associated with land degradation. As you learned in Week Two, the lack of clean water and poor hygiene can cause higher incidences of water- and food-borne diseases (Land degradation and desertification, n.d.). Likewise, in Week One you learned that wind erosion and air pollutants cause higher rates of respiratory diseases in populations. Dryland climates, created through land degradation and desertification, lead to poverty, emigration, and overall reduced human well-being. The migration of populations from dryland areas to more hospitable areas often leads to the spread of infectious diseases.

Land degradation and desertification also contributes to biodiversity loss. Biodiversity is an integral part of functioning ecosystems and affects food production. Biophysical diversity of vegetation ensures sustainable productivity of soils. It is also instrumental in soil conservation and in the regulation of rainfall infiltration, surface run-off, and local climate (Land degradation and desertification, n.d.). A variety of foods is needed to maintain human health. The nutritional composition between foods varies significantly and biodiversity loss affects the micronutrient availability in a person’s diet (Biodiversity, n.d.). In essence, our health is connected to the health of different species and on the natural functioning of its ecosystems (Chivian and Bernstein, pg 5). Enhanced food production including the use of fertilizer and pesticides as well as the introduction of crop varieties and cropping patterns significantly contributes to biodiversity loss (Biodiversity, n.d.).  Biodiversity is also important for medical and pharmacological discoveries. A loss in biodiversity could limit the discovery of new medical treatments and the creation of new drugs (Biodiversity, n.d.).  Traditional medicines are an important part of health care around the world and communities rely on natural resources collected from ecosystems for medicine (Biodiversity, n.d.).

This is a basic summary of the consequences to human health and well-being that result from land degradation, desertification, and biodiversity loss within an ecosystem. You will want to pay close attention to the movie and your readings, however, as you will need to discuss the factors that lead to an ecosystem collapse and the related health consequences in more detail in your discussion post.  

First, read the following required resources:

• World Health Organization (2005). Ecosystems & Human Well-Being: Health Synthesis (Links to an external site.)Links to an external site. (pp. 1-10). Retrieved from http://www.who.int/globalchange/ecosystems/ecosys.pdf?ua=1
• Millennium Ecosystem Assessment. (2005). Ecosystems and Human Well-Being: Desertification Synthesis (Links to an external site.)Links to an external site.(pp.12-21).  Retrieved from Ecosystems and Human Well-Being: Desertification Synthesis (2005) [pdf 3Mb]
• Asfray, A., Giri, C., Govil, K., Hartemink, A., Holmgren, F. Keita-Ouane, F…Zhongze, W. (2007).Land. In United Nations Environment Programme (Publisher), Global Environment Outlook 4: Environment for development (Links to an external site.)Links to an external site.(pp.81-114). Retrieved from http://www.unep.org/geo/geo4/report/03_Land.pdf
• Chivian M.D., Eric M.D.  & Aaron Bernstein M.D., M.P.H. (2010). How Our Health Depends on Biodiversity (Links to an external site.)Links to an external site.. United Nations Environment Programme.  Retrieved from http://www.chgeharvard.org/sites/default/files/resources/182945%20HMS%20Biodiversity%20booklet.pdf

Second, watch the following documentary film:

• Bowie, G. (Writer & Director). (2000). The collapse of the Aral Sea ecosystem (Links to an external site.)Links to an external site. [Video file]. Retrieved from https://fod.infobase.com/OnDemandEmbed.aspx?Token=29877&aid=18596&Plt=FOD&loid=0&w=640&h=480&ref=

Reflect: As you read the reports and watch the film consider the following.

• How would you define land degradation, desertification, biodiversity, and ecosystem collapse?
• What are the primary social, economic, and policy factors that contribute to ecosystem degradation?
• How do these factors put pressure of food systems and the availability of food and water in affected areas?
• How does the loss of biodiversity impact human health?
• How can you incorporate the information you learned about air pollution and changes to the hydrological system from Weeks One and Two into this discussion?

Write:  Social, economic, and policy factors and health consequences of an ecosystem collapse.

From your required resources you have learned that land degradation and desertification is a direct result of many economic and political decisions about the development of certain areas. In the first paragraph of your post consider the social, economic, and political factors that led to collapse of the Aral Sea ecosystem and the resultant effect on human health and well-being within the community shown in the video.

In the second paragraph summarize the ecological (including biodiversity) and health problems within the community that resulted from the collapse of the Aral Sea. In your response you should consider access to food and the availability of health care systems and drugs. Explain the role economics and policy decisions have on the response to the health crisis in this region.

Guided Response: Your initial post should be at least 300 words in length. Support your claims with examples from the required material(s) and/or other scholarly resources, and properly cite any references. Respond to at least two of your classmates’ posts in no less than 100 words by Day 7.