1 / 17

Desertification

Desertification . Rachel Vincent, Adam Ali, Yuna Farah Ecosystems Ecology Spring 2014. What IS Desertification?. “Conversion of productive, arable areas to non-productive” Change in… Soil Properties Vegetation Climate Results in…

davin
Download Presentation

Desertification

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Desertification Rachel Vincent, Adam Ali, Yuna Farah Ecosystems Ecology Spring 2014

  2. What IS Desertification? “Conversion of productive, arable areas to non-productive” Change in… Soil Properties Vegetation Climate Results in… Loss of ecosystem services  food security, carbon sequestration, supply of forage, fibers & wood, maintenance of biodiversity Stress in human societies

  3. What’s the Nature of Desertification? • Occurs mainly in arid, semi-arid and sub-humid areas • Drylandsare very vulnerable to changes • A form of land degradation • Reduction of biological or economic productivity of dry lands • Consequences = loss of soil fertility • Degrades dry but productive land so that it can no longer sustain life • Affects large dryland areas  1/3 of world population resides in drylands • If disturbances (climatic change or human causes) are severe enough, land productivity might not reversible

  4. Causes of Desertification • Human Causes • Contribute the most • Overgrazing • Over-cultivation • Tillage • Irrigation • Inefficient irrigation • Over-irrigation • Deforestation • Population • Growth & migration • Climatic Causes • Aridification fertile regions becoming increasingly dry • Precipitation  limited rainfall • Water scarcity • Increases in drought • Anthropogenic increase in greenhouse gases • Affect precipitation pattern

  5. Why is this important to people? Increase of bare soil General decrease in ecosystem services & productivity Shifts in types of vegetation

  6. What are the Causes of Desertification? Poor land management Anthropogenic forces  migration & conflicts Climate change

  7. Desertification has resulted in… • Agricultural declines • Famines • Loss of income • US loses $42 billion yearly • Reduction in resilience • Due to climactic variability

  8. How does this problem alter the flow of energy, water, and nutrients throughout the system? • Less vegetation > more erosion/ dust emissions • High levels of dust in the atmosphere can lead to cooling • Dust emissions reduce precipitation and impede plant growth • Less vegetation > less evapotranspiration > less precipitation recycling • Less vegetation > less transpiration from plants, same amount of evaporation (unproductive) and can lead to salt accumulation

  9. How does this problem alter the flow of energy, water, and nutrients throughout the system? • Increased run-off and evaporation > less water for infiltration and transpiration • Loss of vegetation > change in atmospheric CO2 • Increased albedo from vegetation loss • Surface temperature increase from decrease soil moisture • High temp/low precipitation leads to low soil organic matter • Soil degradation > infertile soil

  10. How to Address and Remediate Desertification Identification Mitigation Control Reversal

  11. Identification Biophysical Land cover change Biodiversity Soil fertility Economic Market efficiency Decreasing crop yields Social Increasing migration from rural to urban areas Declining health Political Declining state power Immigration-related issues

  12. Mitigation • “The success of biophysical remediation and mitigation measures depends on the the existence of favorable societal conditions…Local and ‘stakeholder involvement’ appear to be crucial” • COLLECTIVE ACTION!

  13. Control Importance of identification and monitoring Soil, wind, water erosion control Ex: mulching crop residues, create vegetation shelterbelts controls wind erosion Manage grazing and livestock mobility  maintains biodiversity

  14. Reversal IMPOSSIBLE TO REVERSE BUT… Improve agriculture & promote sustainability of resources Soil erosion control Salinity remediation Manage grazing/livestock Biodiversity among crops Improve & introduce better manmade systems/management

  15. References • Bakr, Noura, David C. Weindorf, Mohamen H. Bahnassy, Mohamend M, El-Badawi. “Multi-temporal assessment of land sensitivity to desertification in a fragile agro-ecosystem: Environmental indicators.” Ecological Indicators 15 (2012): 271-280. Print Verón, S.R., J.M. Paruelo, M. Oesterheld. “Assessing desertification.” Journal of Arid Environments 66 (2006): 752-763. Print. • D’Odorico, Paolo, AbinashBhattachan, Kyle F. Davis, Sujith Ravi, and Christiane W. Runyan. "Global Desertification: Drivers and Feedbacks." Advances in Water Resources 51 (2013): 326-44. Print. • Jiang, Zhongcheng, YanqingLian, and Xiaoqun Qin. "Rocky Desertification in Southwest China: Impacts, Causes, and Restoration." Earth-Science Reviews 132 (2014): 1-12. Print. • King, Caroline, and David S.g. Thomas. "Monitoring Environmental Change and Degradation in the Irrigated Oases of the Northern Sahara." Journal of Arid Environments 103 (2014): 36-45. Print. • Sivakumar, M.V.K. “Interactions between climate and desertification.” Agricultural and Forest Meterology 142 (2007): 143-155. Print • Zhao, Ha-Lin, Jin Li, Ren-Tao Liu, Rui-Lian Zhou, HaoQu, and Cheng-Chen Pan. "Effects of Desertification on Temporal and Spatial Distribution of Soil Macro-arthropods in Horqin Sandy Grassland, Inner Mongolia." Geoderma 223-225 (2014): 62-67. Print.

More Related