Week 2 | Q1: Deforestation in the Ancient World
September 23rd, 2009 at 13:30by Alison Cole
Our first two references deal with the topic of ancient deforestation and its cascading effects on cultural survival. Williams (2000) is a great overview of pre-1500 AD deforestation in North America and Europe and Shaw (2003) covers the possibility of deforestation as a cause for the Maya collapse.
Reading through these papers, in addition to any other resources you find, lets begin a discussion surrounding historical deforestation in the ancient world. Is there physical evidence of this? How are environmental archaeologists determining when and where it happened?
Posted by Alison Jean Cole,
in Additional References, Syllabus Discussion
September 26th, 2009 at 2:24 am
In the article by Lara O’Sullivan is with the School of Humanities, and Andrew Jardine, they highlight the complex interactions between anthropogenic ecological change and mosquito-borne disease patterns. A historical case study of a possible link between deforestation and increase in malaria disease burden show that the experience of Rome is being repeated today. This requires therefore careful management of agricultural clearing and for a multidisciplinary perspective in policy development on the issue, particularly in regions where there are already indications of escalating disease rates.
October 4th, 2009 at 10:55 pm
In a research carried out by Farella et al at the texas A and M University , Departmenst of Physical Sciences , on Deforestation Amazon the concentration and biomarker compositions of sedimentary organic matter as well as fine and coarse suspended particles were analysed to identify the impact of deforestation on the transport of terrigenous organic matter in the Rio Tapajós, a major tributary to the Amazon. Substantial shifts in the concentration and composition of recently deposited sedimentary OM suggest that intensive deforestation over the last few decades has considerably modified the natural inputs of sedimentary materials to the aquatic ecosystems by disrupting the terrigenous fluxes of humus and soil materials from the drainage basin. The observed compositional changes of bulk OM and land derived biomarkers (e.g. lignin) in recent sediments illustrate a sedimentary enrichment in OM from soil horizons that, under normal forest cover, tend to be retained in the drainage basin. The study illustrates the relevance of using OM oxidation products in sediment profiles to evaluate deforestation impacts on aquatic ecosystems and to characterize the nature of eroded soil materials, complementing studies on mineral/metal cycling
The effects of deforestation can be both local and global. In the local forest ecosystem, trees, water, soil, plants, and animals are all dependent on one another to keep healthy. When trees are cut this natural balance is upset and the important functions that trees perform such as holding the soil in place, protecting groundwater, and providing food and shelter for plants and animals cannot take place. Overcutting forests and the disruption of the forest ecosystem are causing erosion of soil, the drop in water tables , loss of biodiversity as plant and animal species become extinct, loss of soil fertility, and the silting up of many water bodies. When the process continues for a long period of time or over a large area there can be total environmental collapse. Parts of the world that are now desert, such as Syria, Iraq, and Lebanon, were once covered with healthy forests.
Globally the effects of deforestation are more difficult to see. Forests play an important part in the greater natural cycles that make and affect the weather and that clean the air in our atmosphere. They keep the hydrological cycle healthy by putting water back into the atmosphere through transpiration , making clouds and rain. They also capture carbon dioxide produced by the burning of fossil fuels from the atmosphere, replacing it with oxygen and thus reducing the risk of global warming. If too many forests are cut these important functions cannot be carried out. The result could be less rain, higher temperatures, and more severe weather patterns in many regions of the world.
Local and global effects of deforestation are beginning to have devastating consequences. Some areas in West Africa, for example, are already feeling the effects of lost precipitation , higher temperatures, and increased desertification . Other areas, like Venezuela, have experienced devastating floods due to treeless slopes being unable to catch the rain from heavy storms, sending it rushing into valleys. All of these problems impact the environment, but they also take a heavy toll on humans.
There are several things that can be done to decrease deforestation and to offset its negative effects. Many communities are trying to reduce the burden placed on forests by instituting recycling programs and by using alternative materials like plastics in place of wood. In business, companies have begun to use wood products that come only from certified renewable forests that are carefully managed to ensure that they are cut in a sustainable way. Alternative methods of agriculture, such as agroforestry and permaculture , promote the use of trees and the diversification of crops to reduce the stress placed on forests by large-scale agriculture. Protecting forests by creating parks and reserves is another strategy to keep forest resources intact. For those areas that are already devastated, great efforts are being made to replant once-forested lands with native species.
Other efforts are aimed at changing our ideas about the value of forests. Economists are now trying to calculate the true value of the forest as an ecosystem and the benefits it gives as a whole, not only the value of cut logs. This reevaluation will help us make more informed choices about how we use forest land. All of these efforts have helped reduce the burden on the forests, but cutting continues unsustainably. Without the cooperation of all humans to create alternative strategies to deforestation, it will continue with terrible results for the health of our planet.
I think this helps in a way
November 15th, 2009 at 1:59 am
Thank for taking the time to share that. Lets hope we can figure a way to change things in this part of the world