Decline of the Aral Sea

THE CASE OF THE ARAL SEA

The Case of the Aral Sea

Literature Analysis/Article Summary

In the article “Examining long-term natural vegetation dynamics in the Aral Sea Basin applying the linear spectral mixture model”, authors Su et al. (2021) sought to analyze the causes of changes in vegetation cover in Aral Sea using ecological dynamics which are major contributors of social and economic development in the region. To analyze the said changes, the authors conducted a study between the years 2000 and 2018. Three steps were deployed. The first step involved the use of LSMM method to differentiate between natural and cultivated vegetation. In the second step, the authors monitored the long-term and large scale cover of the land cover. The third stage involved elimination of interference on vegetation coverage from cultivated land. To analyze the changes in vegetative cover as well as their characteristics, the authors used the Mann-Kendall trend test, Sen Trend analysis, and trend line analysis. In addition, the authors explored the factors that led to change using multi-source data.

From the study, the authors found that the Aral Sea basin had lower vegetative cover which only accounted for approximately 6.26% of the overall drainage. The results also showed that the vegetative cover and water bodies in the area had significantly increased from the year 2000. The authors also found that the desert area of the Aral Sea accounted for 62.85% of the overall basin while the water body area of the said sea accounted for only 5.15%. To a large extent, the desert was degrading - which made the temperatures in the area to be high, and the waters to evaporate quickly, effectively limiting crop growth.

One of the factors that contributed to lower vegetative cover was climate variability. According to Su et al. (2021), Aral Sea is located in a semi-arid area. For this reason, there were climatic changes in the Aral region which affected the physiology and composition of vegetative cover in the area. For instance, precipitation rate in the area was high and for this reason, only a small percentage of crops were rain-fed. Apart from climatic factors, the authors also found that human activities also contributed to degradation of the Aral Sea. Agriculture was one of the human activities that the authors found to be contributing to low vegetative cover as well as human production activities, migration, population distribution, and population coverage. With regard to agriculture, the authors found that as the irrigated farmland expanded, the natural vegetation degraded. As a consequence, the Aral Sea dried leading to migration of people to Uzbekistan and Kazakhstan.

The article relates to ecological principles and sustainable practices given that while examining the dynamics in vegetation, the piece also shows how the said principles and practices were ignored. For instance, the article discusses how the flow of energy was ignored when the vegetative cover in the area decreased. The cycling of matter and population dynamics principles were also not taken into consideration. It is important to note that human activities contributed to the growth of industries. This resulted in economic growth as well as population growth which further led to decline of vegetative cover. It is also important to note that sustainable practices were not practiced. This is more so the case given that water conservation methods were not used in the area. In essence, Su et al. (2021) suggest that unreasonable irrigation of farmland was practiced and a third of river water was also used for cultivating land.

Case Study Final Report

Introduction

The Aral Sea - which is located in Central Asia - was the fourth largest lake in the world. According to Glantz (2007), the said lake was fed by river Syrdarya and river Amudarya. However, between 1960 and 1970, the two rivers that fed the said lake were diverted. As a consequence, volume of water at Aral Sea declined at a faster rate creating massive environmental problems in the Aral Sea area. As Crighton et al. (2017) found out, the environmental problems that were caused by degradation of Aral Sea significantly heightened health problems among the people living in the Aral Sea area. While degradation of the Aral Sea has largely impacted the lives of people in the area, there would be need to come up with ways of managing the said sea so as to address the ecological principles that were ignored during the degradation of the Aral Sea. Therefore, this case study aims to determine the activities that led to degradation of the Aral Sea as well as how the people in the area were impacted by the said degradation. In addition, the case study report would also address the tipping point in degradation of the Aral Sea, what has been done to restore the ecosystem, and what can be done to address the ecological principles that were ignored during degradation of the said sea. Towards the end, the study would also provide suggestions for restoration of the Aral Sea.

Human Activities that led to Degradation

It is important to note that human activities largely contributed to degradation of the Aral Sea. Su et al. (2021) found that large scale irrigation of agricultural land was one of the reasons the Aral Sea degraded. Various authors further agree with Su et al. (2021) that intensive agricultural farming was a major contributor to degradation. For instance, Glantz (2007) points out that the soils in Central Asia were perfect for the production of cotton. In addition, the climate in the area was also warm making it suitable for cotton farming. According to Clighton et al. (2017), the Aral Sea was fed by two rivers, i.e. Syrdayar and Amudayar - which were seen as crucial sources of water for cotton farming. Further, the authors suggest that the area had a huge exploitable population to work in the cotton farms. The Soviet government which was in power at the time was interested in the acquisition of self-sustainability in cotton production (Clighton et al., 2017). To achieve the said goal, the Soviet government imposed modern methods of cotton farming – resulting in the diversion of large amounts of water from the Aral Sea to expand irrigation canals. Essentially, the two rivers that fed the Aral Sea were diverted for cotton irrigation. The said diversion of water from the two rivers led to high levels of evaporation and accelerated decline of water levels at Aral Sea, i.e. owing to reduced inflow of freshwater (Aladin et al., 2019). As more water was being used for irrigation, the water became saline and the salts from the lake were transported by wind, exposing the sea bed of the Aral Sea. Apart from degradation of the Aral Sea owing to diversion of water from the said sea, it is also important to note that people actively used pesticides and herbicides for cotton farming (Glantz, 2007). The massive use of pesticides increased the levels of toxicity in the Aral Sea.

Su et al. (2021) points out that the effects of human activities on vegetation in Aral Sea was more direct and rapid. For instance, human activities led to economic development in the Aral Sea area. As a result, the total population in the area also increased rapidly. Based on available statistics, the authors found that human activities contributed to choice of technologies used in the Aral Sea area. For instance, the authors suggest that there was a growth in power industries, non-ferrous metallurgical industries, and petrochemical industries. However traditional industries such wood and light industries experienced reduced growth. The rapid use of technologies owing to industrialization further affected the vegetation in the Aral Sea area. Human activities that led to degradation of the Aral Sea happen to also have a global affluence. This is more so the case given that a decline in vegetation cover in the Aral Sea did not only affect the Aral area, but also affected the economic activities and ecological environment of the areas neighboring the Aral Sea. In essence, vegetation cover impacts various essential aspects which are inclusive of, but they are not limited to; water resources, water balance, water vapor transport, and atmospheric circulation. Therefore, the rapid degradation of the Aral owing to irrigation led to a reduction of water sources in other regions in ways that could impact global climate change (Su et al, 2021).

While degrading the Aral Sea, various ecological principles were ignored. For instance, the movement of energy in the said ecosystem was ignored. In essence, the Aral Sea was a freshwater ecosystem and, thus, supported various prokaryotes, protists, fungi, plants, and animals. Therefore, when the Aral Sea was degraded, the said organisms were also affected as fauna and marine species were destroyed (Aladin et al., 2019). In addition, since each organism requires energy, the persistent biomagnification owing to increased use of pesticides and herbicides increased toxicity leading to poisoning. Another ecological principle that was ignored during degradation was the fresh water cycle and supply of fresh water. In essence, the decrease in water levels in Aral Sea affected the water cycle. This is more so the case given that there the rate of evaporation from the lake decreased, as did the process of condensation and precipitation. According to Su et al. (2021), the decrease of vegetation cover led to hydrological changes whereby it not only impacted the regional water resources, but also impacted water balance, water vapor transport, atmospheric circulation, and precipitation. The population dynamics in the Aral Sea area were affected. This is more so the case given that as the vegetation cover decreased, the rate of migration and population distribution was also affected (Su et al., 2021).

Natural Changes that Exacerbated the Degradation.

The two natural changes that exacerbated the degradation of Aral Sea were changes in temperature and precipitation - whereby precipitation was the major natural factor (Su et al., 2021). According to the authors, temperature affected the vegetation growth cycle while precipitation affected the physiological changes as well as the composition of vegetation. With regard to temperature, it is important to note that the Aral area was warming owing to high temperatures in the area. This is more so the case given that the Aral Sea basin happens to be in a semi-arid region. However, temperatures would significantly drop during winters leading to changes in vegetation cover in the Aral Sea. On the other hand, Su et al. (2021) also found that the precipitation in the Aral Sea would slightly increase. In particular, the trend of precipitation in Kazakhstan was increasing. For this reason, crops in the Aral Sea area that were fed by rain accounted for only 10.12% of the entire cultivated land.

Effects of Degradation to Ecosystem

As the ecosystem in Aral Sea was affected, the people living in the Aral Sea area were also impacted. With regard to the ecosystem itself, Clighton et al. (2011) suggest that the Aral Sea disappeared owing to environmental mismanagement. In addition, the toxic agricultural chemicals also contaminated the water, soils, and the air in the region. On the other hand, the population in the Aral region experienced various health problems as a consequence of the turn of events. For instance, Clighton et al. (2011) found that people living in Aral region experienced birth defects, respiratory illnesses such as tuberculosis, cancers, diarrheas, renal tubular dysfunction, and anemia. One of the major health problems in the Aral area was anemia which was linked to diminished diet and high poverty levels owing to decline in agriculture and collapse of fishing industry. Further, Clighton et al. (2011) suggest that poisoning as a consequence of increased susceptibility to heavy metals also increased the risk of anemia owing to contaminated environment. Cases of diarrhea especially among children were also high. The said cases were also associated with drinking of contaminated water and poor sanitation in the Aral Sea area. Essentially, the high levels of salinity in the Aral Sea bed led to saline water which was consumed by people living in the region. With the said health problems in Aral Sea area, the mortality rate -especially among infants - increased rapidly (Clighton et al., 2011).

Tipping Point to the Ecosystem Degradation

The critical point for the degradation of the Aral Sea was observed when the Aral farmland was abandoned. According to Su et al. (2021), the Aral Sea region became dry owing to reduced water and vegetative cover. As a consequence, people who were living in the said region migrated to Uzbekistan and Kazakhstan which had better water supply and more vegetative cover than the Aral Sea.

Restoration of the Aral Sea

Despite the degradation of the Aral Sea, it would be prudent to note that some actions have in the past been taken to partially restore the said sea. For instance, attempts were made to preserve waters from Syrdayar whereby, using the local sand, a dam was built even though there was limited funding (Aladin et al., 2019). However, the said dam was destroyed after the sand was washed away by water owing to increased water pressure. Thereafter, the World Bank donated funds in 2005 for construction of a proper dam and since then, salinity levels decreased due to freshwater from Syrdayar River. In addition, trials were also made during this time to increase the productivity of fish in the region by introducing certain invertebrates and commercial fish species. However, Aladin et al. (2019) points out that the said plan was not successful given that the waters in the region were saline and, thus, could not be tolerated by the said species. Presently, there are plans to construct a dam at the belt of Bolshoy Sarycheganak Bay which will spill water into Small Aral. In addition, a channel would also be constructed from Aklak structure which will divert water from Sry Darya into the said bay.