Introduction
Over the past century, mankind has been forced to recognize and appreciate the delicate balance that exists between him and the environment. During this period, there have been environmental changes, which have had detrimental effects such as desertification, floods and droughts in different regions across the world. However, Spoolman and Miller (2011) assert that environmental changes (such as the ice age among others) have been in existence for thousands of years. As a result, mankind should adapt himself to these changes in order to cope effectively. According to the authors, human factors have contributed significantly to environmental changes (Spoolman & Miller, 2011). The author explains that as a result of rapid civilization and industrialization, mankind has played an active role in the degradation of his environment. Through various human activities over the years, there has been a significant increase in soil, water, air and noise pollution. These forms of pollution have to a large extent contributed to the aforementioned environmental changes such as desertification.
Desertification has been documented as being a major threat to the survival and livelihoods of millions of people who rely on the advantages drylands ecosystems have to offer (Veron, Paruelo & Oesterheld, 2006). With this in mind, it would be a worthwhile endeavor to explore various aspects of desertification in order to better understand this evident phenomenon. Therefore, this paper shall set out to analyze desertification in regard to its causes and effects on the ecosystem. Recommendations on how this life-threatening occurrence can be minimized or solved shall also be offered. These objectives shall be achieved through a literature review of credible documented evidence regarding desertification.
Desertification: An integrated overview
Sivakumar (2007) states that over the years, various environmental specialists have come up with different definitions for desertification. The author attributes this to the fact that these specialists defined desertification in accordance to how they viewed it and understood the concept (Sivakumar, 2007). However, the key aspects considered while defining it have been combined to come up with a more suitable definition. Veron, Paruelo and Oesterheld (2006, p.4) define desertification as “land degradation that mainly occurs in dry sub-humid, arid and semiarid areas, emanating from a host of factors that include climatic changes and human activities”. From this definition, it is evident that human activities play a central role in the continuous expansion of desertification in most regions of the world. This is further supported by Hardy (2003) who states human activities such as industrialization are the core cause of global climatic changes.
According to Millennium Ecosystem Assessment (2005), almost all the continents across the world have been affected by desertification with Antarctica being the exception. To further shed some light on the severity of desertification, Millennium Ecosystem Assessment (2005) posted the results of a survey they conducted in 2000, which showed that 41% of the total earth’s surface is made up of drylands. In addition, the results indicated that this vast area was occupied by an approximated two billion people around the world (Millennium Ecosystem Assessment, 2005). These statistics showed that one third of the world’s population was at risk of experiencing desertification and its negative effects on the ecosystems that these people relied upon for sustenance. However, this environmental issue cannot be solved effectively if the causes and effects are not well understood.
Causes of Desertification
From the definition provided earlier, it is evident that there are various direct and indirect factors that cause desertification. Indirect factors include population pressure, social, economical, globalization and procedural factors. On the other hand, direct factors include forms of land use and climatic processes (Millennium Ecosystem Assessment, 2005). Imeson (2012) asserts that indirect factors such as population pressure and globalization have led to a situation whereby land users overexploit natural resources such as wood, water, minerals and soil unsustainably. These natural resources play a pivotal role in enriching the soil and without them; the quality and productivity of land would degrade leading to desertification. Due to rapid population growth on a global scale, the demand for the basic needs has been on the rise (Imeson, 2012). To satisfy this demand, land users have increased pressure on their lands in unmanageable ways. This in turn lowers the productivity of the land, worsens the environmental degradation process and causes desertification (Imeson, 2012).
On the same note, socioeconomic and policy factors have been identified by Millennium Ecosystem Assessment (2005) as contributors to desertification. According to the assessment, desertification has been partly caused by policies implemented to replace pastoralism with active cultivation in rangelands (Millennium Ecosystem Assessment, 2005). 65% of drylands are rangelands, which adequately support pastoralism as compared to crop production (Millennium Ecosystem Assessment, 2005). As such, implementing policies that promote active cultivation or inhibit the ability of nomads to move freely across rangelands has been cited as a possible contributor to desertification (Geist & Lambin, 2004). This is attributed to the fact that such policies limit the occupants’ ability to change their economic activities when faced with climatic changes such as droughts. As such, these lands are subjected to overgrazing and excessive cultivation practices, which contribute to desertification (Stanley, 2009).
As mentioned earlier, globalization also contributes to desertification. In a bid to create a global community, governments and international policy makes have in the recent past implemented policies that promote international trade, exportation and macroeconomic reforms. As a result, land owners have resulted to unsustainable use of their lands in a bid to meet the increased demand locally and internationally. This has contributed to desertification in the sense that land users overexploit their land resources in order to get as much as they can without giving the land ample time to recover efficiently (Geist & Lambin, 2006). The agricultural sector in some countries has enjoyed great financial benefits from selling their produces in international markets. This has mainly been attributed to the removal of international trade barriers. However, removing such barriers without regulating local policies may invariably hearten unmanageable agronomic practices, which contribute to desertification (Millennium Ecosystem Assessment, 2005; Behnke, 2008).
Unsustainable agricultural practices include overgrazing, irrigation and deforestation. According to Stanley (2009, p. 27), overgrazing refers to “having more grazing animals on land than the carrying capacity of that land.” Carrying capacity in this definition refers to the number of animals a given piece of land can efficiently sustain without degrading the environment. In other words, overgrazing refers to the process through which animals are left to graze on available vegetation excessively until the grass cover is depleted. As a result of such practices, land is left bare and soil patches are unprotected. Considering that soil depends on such vegetation covers for nutrients (matter), overgrazing exposes the soil to direct sunlight, soil erosion and the land cannot quickly replenish the nutrients it requires to support germination of plants, leading to desertification (Geist, 2005).
Deforestation on the other hand refers to excessive felling of trees to a point where it affects the climatic conditions of a given region (Sivakumar, 2007). Forests play a significant role in the creation of perennial rainfall. However, recent statistics indicate that an estimated 20% of the world’s forest cover is remaining intact (Geist and Lambin, 2006). Deforestation has been attributed to mankind’s need to find more land for development, agriculture and occupation (Geist & Lambin, 2006). As a result of this, land is exposed to stress associated with such activities, it cannot get the nutrients it requires to support plant life (tree leaves provide enriched nutrients to the soil) and it lacks adequate rain water needed to support natural vegetation (Park, 2001). As a result, the land begins to degrade leading to desertification.
In regard to irrigation in the drylands, it is an established fact that irrigation provides farmers with an avenue through which they can effectively cultivate and practice agriculture in regions that lack sufficient water (Behnke, 2008). As such, irrigation has been cited as a modernized way of improving land productivity (Millennium Ecosystem Assessment, 2005). However, due to increased demand of food across the world, farmers in drylands redirect fresh water from rivers and underground aquifers to their vast farms in order to produce food crops all year long (Helmut & Eric, 2004). Due to this high demand for fresh water, rivers cannot deliver water into various parts of the drylands and underground aquifers are being depleted at an alarming rate (Koohafkan, 1996). Water supports life, as such; inadequate water in various parts of the drylands means that natural foliage cannot grow, thereby degrading the quality of land, which leads to desertification. In addition, various forms of irrigation such as flood and splash irrigation have been attributed to soil erosion, which degrades land by carrying away the fertile layer (top layer) of soil that is needed to support plant life (Meadows & Hoffman, 2002).
Discussion
From the above literature review, it is evident that desertification poses a serious threat to the survival of human, plant and animal life. Point worth noting is that this process of land degradation has been taking place for years and it is getting worse each day. However, there have been efforts made by concerned parties to minimize and reverse the process of desertification (Millennium Ecosystem Assessment, 2005). Despite these efforts, desertification still affects many people leaving them in poverty and affecting their well-being. With these undertones, the question that is left begging is; what can be done? The truth is that policy implementation, land use reforms and protection of natural resources do not account for ignorance among indigenous populations that predominantly occupy the drylands (Davis, 2005). As such, proposed solutions should focus on creating awareness among such inhabitants.
Proposed solutions to Desertification
Throughout this discussion, it has been established that desertification is a dangerous occurrence that needs to be addressed. However, research and policy implementation may prove to be useless if the people who are directly affected by desertification do not understand the factors that contribute to its occurrence. As such, the first viable solution would be to launch consistent awareness campaigns that seek to educate inhabitants of drylands on factors regarding to the causes, effects and solutions for desertification. Ci and Yang (2010) state that educating drylands occupants on the dangers of desertification and viable farming methods have greatly contributed to the reversal and minimization of desertification in Central Asia. This trend should therefore be encouraged to other parts of the world that stand the risk of desertification.
Secondly, policy reforms in regard to international trade, land tenancy and agricultural policies may go a long way in averting further effects of desertification (Ci & Yang, 2010). Support by government in the provision of agricultural technology and infrastructure may help farmers in drylands to adopt sustainable agricultural practices. For example, the government can ensure that farmers have access to fertilizers, seeds and machinery (Ci & Yang, 2010). These resources help maintain the fertility of the soil and assist farmers to practice crop rotation and drip irrigation, which gives the soil the necessary nutrients it requires to support growth (Imeson, 2012). In addition, regulating national and international trade barriers will relieve land pressure that results from high demand for food crops (Millennium Ecosystem Assessment, 2005). If executed properly, these factors will give drylands an opportunity to replenish themselves, thereby decreasing and reversing desertification (Davis, 2005).
On the same note, implementing policies that prevent unsustainable use of natural resources may facilitate the campaign against desertification. Such policies include protection of forests, natural habitats and agricultural land (Millennium Ecosystem Assessment, 2005). The establishment of these policies ensures that natural resources play their role in supporting the ecosystem. For example, protecting forests and natural habitats ensures that land has enough cover to protect it from soil erosion, all the while giving it adequate time to enrich itself with matter (nutrients) emanating from this cover. In addition, this vegetative cover enables the soil to maintain water moisture from rain for long durations, thereby minimizing and reversing desertification (Geist & Lambin, 2006). This is very important because it ensures continuous growth of plants despite exposure of land to practices such as grazing and farming.
Afforestation (process of planting new trees to restore forest cover), mixed cropping and shift cultivation are among the land use practices that may help deter desertification (Klappa, 2005). According to the author, these land use practices gives used land adequate time to recover its natural vegetation and the soil to replenish lost nutrients, thereby minimizing and reversing desertification (Klappa, 2005). If the few recommendations stated above are effectively implemented, the world will be a step closer to restoring all lands affected by desertification.
Conclusion
The effects of desertification on our ecosystems are far reaching and cannot be ignored. This paper set out to explore various aspects of this occurrence. To that end, a detailed analysis of the possible causes and effects of desertification have been offered and recommendations as to how best the issue can be resolved give. It has been established that human activities play a pivotal role in the occurrence of desertification. As such, we owe it to ourselves to work together with governments and other concerned parties as hey try to find a lasting solution to this problem. It should be noted that desertification not only affects the inhabitants of drylands, but also has far reaching health, social and economic effects on other people (Hassan et al, 2005). As such, it should not be viewed as a problem to drylands occupants, but instead, it should be viewed and approached as a universal disaster in the making.
References
Behnke, R. (2008).The Socio-Economic Causes and Consequences of Desertification in Central Asia. New York City: Springer.
Ci, L., & Yang, X. (2010). Desertification and Its Control in China. New York City: Springer.
Davis, D. K. (2005). Indigenous knowledge and the desertification debate: Problematising expert knowledge in North Africa. Geoforum, 36(4), 509-524.
Geist, H. (2005). The causes and progression of desertification. Farnham: Ashgate Publishing, Ltd.
Geist, H. J., & Lambin, E. F. (2004). Dynamic causal patterns of desertification. Bioscience, 54 (9), pp. 817-829.
Geist, H. J., & Lambin, E. F. (2006). Land-use and land-cover change: local processes and global impacts. New York: Springer.
Hassan, R. M., et al. (2005). Ecosystems and human well-being: current state and trends: findings of the Condition and Trends Working Group of the Millennium Ecosystem Assessment. London: Island Press.
Hardy, J. T. (2003). Climate change: causes, effects, and solutions. Boston: John Wiley and Sons.
Helmut, J., & Eric, L. (2004). Dynamic Causal Patterns of Desertification. BioScience, 54 (9), 817-829.
Imeson, A. (2012). Desertification, Land Degradation and Sustainability. Boston: John Wiley & Sons.
Klappa, S. (2005). Fallow farming: exploring subsistence in Krisa, far northwest Papua New Guinea and beyond. Chicago: University of Kent.
Meadows, M., & Hoffman, T. (2002). The nature, extent and causes of land degradation in South Africa: legacy of the past, lessons for the future? Area, 34 (4), 428-437.
Millennium Ecosystem Assessment, 2005. Ecosystems and Human Well-being: Desertification Synthesis. World Resources Institute, Washington, DC.
Park, C. (2001). The environment: principles and applications. London: Routledge.
Sivakumar, M. K. (2007). Interactions between climate and desertification. Agricultural and Forest Meteorology, 142 (2–4), 143-155.
Spoolman, S., & Miller, G. (2011). Living in the Environment: Principles, Connections, and Solutions. New York: Cengage Learning.
Stanley, J. (2009). Hill Country Landowner’s Guide. Texas: Texas A&M University Press.
Veron, S. R., Paruelo, J. M., & Oesterheld, M. (2006). Assessing desertification. Journal of Arid Environments, 66(4), 751-763.