Desertification: Causes and Existing Solutions

Abstract

The humanity has always encountered numerous challenges such as famine, epidemic diseases, wars, etc. that provoked serious crises and several times posed a threat of human extinction. During recent centuries it became evident that those problems are of a global character and cannot be solved within a local community; due to the scale of such problems, they can be effectively combated only if the nations unite their forces. Wars and ecology are the worst world’s disasters. Despite all the efforts, ecological condition becomes more severe, and the confrontation between Muslims and the rest of the world also increases.

Introduction

The present project deals with such ecological problem as desertification. The United Nations Convention to Combat Desertification defines it as “land degradation in arid, semi-arid and sub-humid areas resulting from various factors including climatic variations and human activities” (UNCCD Art.1.a). The scale of desertification is really frightening. According to the Worldwatch Institute, the planet loses over 24 tons of fertile topsoil annually (Brady 2). Every year, 12 million hectares of soil are lost at an average rate of 23 hectares a minute (“Background Information on Desertification”).

Common Misconceptions About Desertification

It is worth noting that there are some common misconceptions about desertification. First, the issue of desertification creates in people’s imagination a picture of sand, wind and the burning sun, such as Sahara. Actually, it is the most extreme image of a desert that does not always correspond to the reality. The second idea is that desertification spreads like disease around already existing desert, such as in sub-Saharan Africa. This statement is only partially true since severe deterioration of the soil can occur due to the human activity where there is no desert in the neighborhood (such desert areas as in Spain or Slovakia, for example). Third, people refer desertification to the recent centuries or years. The truth is that it happened more than once in the history of humanity causing migrations of people and downfall of great civilizations (e.g. over 1500 years ago in Mesopotamia) (Dregne 11-12).

Historical Background

The notion of desertification was introduced in 1949 by famous botanist and ecologist Aubreville (Dregne 4). In the 1950s, this problem became a worldwide concern. Attention of the world community was drawn to the problem of desertification for the first time in 1951 by UNESKO with its Major Project on Scientific Research on Arid Lands. It provided reasons for serious consideration of the problem, creation of foundations, institutes and numerous research. A UNO International Conference on Desertification was held in Nairobi, Kenya, in 1977; the result of the conference was the approval of the Plan of Action to Combat Desertification that is implemented within the United Nations Environment Program (Dregne 1-3). In 1994, the United Nations Convention to Combat Desertification was established, which is a “sole legally binding international agreement linking environment and development to sustainable land management” (“Background Information on Desertification”). The concern is strengthened by the fact that more than 50% of the Earth’s ecosystems lie in drylands, that is sub-humid and semi-arid areas. One third of the planet’s population (2.1 billion people, more than 110 countries) lives in dryland, and they will immediately suffer from degradation of land (“Background Information on Desertification “).

Causes of Desertification

The two major causes of desertification are climatic change to the human activity. Whereas climate cannot be immediately affected by the people, the second major cause is subject to closer examination. These practices are always excessive or short-sighted. Human activities that contribute to desertification are the following: overgrazing, overcultivation, deforestation, and poorly drained irrigation systems (Brady 4).Statistics shows that over 70 per cent of the 2.5 billion of agricultural land all over the world are already degraded. Due to overgrazing, vegetation cover of the soil is removed after which it is subject to wind and the sun. Concerning wildlife, dryland ecosystems regenerate after grazing animals migrate to another place. It is different from that when the domestic cattle staying on the same pastureland for a long time or returns after a short period. Huge flocks of animals trample the ground pressing it on the deeper levels, when they remain long at the same place. They also pollute the land by dunging and urinating. After cattle consume perennial plants covering the soil, the annual plants that cannot provide that level of protection instead (Savory 2). Digging water wells for the cattle also accelerates desertification since water supply for vegetation in the area becomes scarce. Most evident effect of overgrazing is observed in Australia, North America, and Africa.

Overcultivation exhausts the soil, which is not able to regenerate under unfavorable weather conditions. Moreover, cultivated soil loses humidity and suffers from erosion much more than in the natural course. In Nigeria, 351,000 hectares of grassland and cropland is converted into desert each year (Brady 2).

Due to deforestation, soil suffers from erosion and run-off. Trees planted instead of the fallen woods can only partially reimburse the loss since they do not fulfill all the functions of the original forests in the ecosystem. Not only tropical woods are being devastated, but the trees are thatched in the whole world mainly for firewood, furniture, and construction poles. Another problem is fires which occur often enough in natural way; moreover, rural farmers burn trees and bushes to clear new areas for agriculture, to drive off wild animals, or to clear grassland for new grass growth. Brady states that an estimated 26 hectares of forests are lost every minute worldwide “due to agricultural pressure, road building, forest fires and illegal logging” (5).

Poorly drained irrigation systems contribute to the increase of salt level due to excessive evaporation of water; salinization also makes soil less fertile. Brady lists a number of indirect causes of desertification. Among them there are loss of traditional knowledge, production of cash crops, poverty, population growth, and even gender bias (5). Thus, desertification is a complex problem with several constituents, and it can be solved only through the complex approach.

Traditionally, nomadic cultures exercised so-called gentle presence following natural cycles and living in symbiosis with the surrounding nature. Since crop farming has been introduced into the area, the pasturelands reduced, and there is less space for migration with flocks. A switch to profitable monoculture, such as peanuts or millet in Nigeria, exhausts soil and reduces biodiversity; it leads to oblivion of traditional crops grown in the area for centuries. Crops grown at the same place for years develop diseases and reduce productivity. Moreover, they demand expansion to the new lands, which leads to deforestation and decrease of pasturelands (“Desertification – a Threat to the Sahel”).

Poverty is a result of deforestation, but is also the reason of such a process. Extreme poverty often does not leave much choice, but the use of immediately extractable natural resources. The meager profit people get from it is just enough to survive. Due to such mode, there is no possibility to cultivate the land.

Population pressure leads to the increased consumption of water, fuel wood, construction wood, and foodstuffs. The population of the Sahel increased from 274 million people in 1968 to 698 million in 1998, whereas urban population grew by 5 and rural population increased only by 2% (Brady 6).

Antropogenic Causes of Desertification

Gender inequality is one of the possible reasons. Men have dominating role in the traditional societies; they are granted access to the land that was earlier used for growing food by the women. Traditional societies do not allow women to play a role other than childbearing. Soil degrades because people exhaust it with their excessive practices; they practice that way of agriculture because they are not informed of the consequences and do not care about the corollary in search of immediate profit; it also happens because the governments do not discourage soil-exhausting practices. The more people farm, the poorer the soil becomes; the poorer the soil is, the more they need to farm to earn for a living.

Regarding the issue of responsibility for desertification, apart from the acts of nature, it is clear that all society layers contribute their share. The governments are responsible through economic policies directed on obtaining quick income from excavation of the natural resources, production of cash crops, etc. Middle income class is usually responsible for devastation of new areas in order to expand arable lands or pasturelands without considering the surrounding places. Poverty-stricken population is immediate contributors into development of the problem by exploiting soil or collecting firewood, especially on the African continent.

Existing Desertification Solutions

Desertification cannot be regarded as a single problem, there are more reasons for such a process, and it causes a range of troubles to biodiversity, eco-safety, poverty eradication, socio-economic stability, and sustainable development.

The threat of desertification is considerable enough to invest time and effort into the studies. Research has been made to study the methods of soil recuperation. Such remedies are mostly symptomatic, providing solution only to a certain cause. It is offered that overgrazing should be solved by herding flocks in traditional manner. Overcultivation is countered by sustainable agriculture, deforestation - by reforestation, irrational use of irrigation systems – by development of efficient water saving techniques. However, it is vital to change the minds of people at the level of individuals, communities and governments because the methods will not be successful if they are introduced from the side.

Planting trees proved to be effective in eliminating deserts and recovering soil fertility. It refers to indigenous plants and trees that have naturally developed mechanisms of withstanding draughts. Trees effectively stop erosion by stabilizing the soil, protect the land from excessive heat and wind, retain moisture and absorb CO2. This method is successfully used around Sahara; China also created its green belt of trees to stop the desert.

Allan Savory disputes some of the existing desertification solutions, such as resting the land by removing or reducing cattle, planting grass and/or trees, developing irrigation techniques, using fire to remove dead material. He claims that they are not effective because they do not tackle the cause. He states that it is a climatic shift that occurred due to land-exhausting practices (“Existing Desertification Solutions”). He suggests holistic approach that means restoration of the ecosystems with the help of cattle imitating movement of the wildlife. The sense is that cattle, provided it does not stay on the same place for a long time, benefits soil since it breaks the soil crust with its hooves (aeration), compacts the upper layer of soil (protection against wind erosion and increase seeds germination), and returns seeds ready for germination into the soil (Savory 2-4).

Sustainable agriculture is a process opposed to overcultivation. Sustainable agriculture is ecology-conscious farming based on the principle of coexistence with the nature. At the practical level, it means transfer to the crops that increase the value of soil (e.g. legumes), planting trees and shrubs to protect soil from erosion (woodlots, windbreaks, shelterbelts), application of methods avoiding erosion (e.g. terraced agriculture), water management (reuse of water, water saving, rainwater harvesting), and sustainable energy use (saving energy, using renewable energy sources). Agroforestry is an aspect of sustainable farming. Brady defines agroforestry as a “practice which integrates high-value multi-purpose trees and shrubs into farming systems” (10). Agroforestry includes alley cropping, riparian buffer strips, windbreaks, and forest farming. In this aspect, sustainable agriculture intervenes with reforestation.

Governments can change their policies encouraging more conscious use of natural resources and introducing programs to support sustainable agriculture, reforestation, irrigation and drainage, etc. They can control large corporations and impose legislative barriers on the practices leading to desertification. Governments can introduce more efficient land management at a legislative level. Nevertheless, introduction of new laws and programs cannot change the mentality of people working on the land. First, educational campaign is necessary to change the consumptive way of thinking. Secondly, actions imposed by government or by any charitable institution, will never bring success, unless they involve participation of the community. People tend to appreciate things created by their efforts, whereas they take for granted things that are delivered without their participation. This is moral effect; practical effect is occurs if people are involved. It means creating jobs and giving opportunity to earn for a living. Thirdly, even well-meant appeals are not likely to change soil and wood exploiting practices applied by the poorest people since they are forced to act in that way by their extreme poverty. Poverty is not a problem that can be solved immediately by any governmental action; therefore, it is necessary to take an action that would mitigate its effect on the surrounding and benefit people’s welfare at the same time.

Prosopis Juliflora as a Multi-Purpose Plant

Desertification, as a complex problem, is difficult and cannot be solved in one project. There is no “universal remedy” able to eliminate it completely. There should be rather a range of measures as complex as the problem itself. Nevertheless, some steps can prove to be effective.

Planting high-value multi-purpose trees and shrubs seems to offer a good though not a cardinal solution to a range of problems. The first and immediate benefit is fixation of soil that enables to arrest erosion and provides the basis for further actions. Second, it solves the problem of firewood for poor the households and keeps them from cutting wood where it damages the environment. Third, arranging such plantations of fuelwood creates job possibilities for the local population.

Considering African circumstances, Prosopis Juliflora (velvet mesquite, a kind of acacia) can be a reasonable solution. It is a perennial non-climbing thorny shrub or tree, up to 12 m tall, with a trunk up to 1.2 m in diameter, native to South America, Mexico, and the Caribbean. It is a multi-purpose plant that can be used for food, forage, wood, environmental purposes (soil fixation). Its great advantage is that it can perfectly grow in semi-arid African conditions due to high tolerance of drought, grazing, heavy soil, sand, saline soils, and weeds. It grows as a weed; thus, it does not need much attention and cultivation. Prosopis bears fruit in 3 to 4 years. Manual harvesting also provides job possibilities. The pods of Prosopis can be used to obtain flour. In its motherland, mesquite pods flour is still produced and highly valued by American Indians. Pods can be made into gruels, sometimes fermented to produce the mesquite wine. The leaves can be used for forage. Prosopis is also a superior honey-plant. The foremost application of the wood is fuel, where Prosopis suits perfectly; moreover, it can be used for furniture, fencepost, pilings, and other wooden items; it can be also applied as a substrate for producing single-cell protein. Toasted seeds are added to coffee. Bark can be used for roofing in Colombia. Gum is required in confectionary and mending pottery. Its juice is popular in the folk medicine as cathartic, cyanogenic, discutient, emetic, poison, stomachic, and vulnerary means. Prosopis makes an excellent fuelwood because it is fast growing, drought resistant, “with a remarkable coppicing power”. It is claimed to be “natural anthracite” due to high heat content, even and slow burning with ability to hold heat well (“Prosopis Juliflora DC”).

The harvest of pods can be estimated at 2,000 to 20,000 kg/ha. Expected wood yields on a 15-year rotation are “75–100 MT/ha, on 10-year rotation, 50–60 MT, suggesting wood yields of 5–7.5 MT/ha/yr over and above the fruit yields” (“Prosopis Juliflora DC”).The price of the wood is nearly $5.00/kg. Mesquite logs, chunks, and chips can be still sold at a better price. Mesquite free pasturelands can produce 1,165 kg/ha forage. As far as its ability to fix nitrogen in the soil is concerned, the Prosopis legumes fix between 155 and 580 kg/ha/yr (“Prosopis Juliflora DC”).

Due the fact that Prosopis is proven to be a highly prospective plant, one should consider its practical implementation. Prosopis can be propagated by seeds (in nature), root suckers, and hardwood cutters. However, “transplanting one-year olds in the rainy season is preferable to direct sowing” (“Prosopis Juliflora DC”).

The feasibility of planting Prosopis is checked by practice since there are plantations in Arizona Desert and in Hawaiian arid areas where the tree has shown good results. Although it is not an African endemic, it is not completely strange to the region because there are other kinds of Mimosaceae growing in Africa.

Advantages of Prosopis as Desertification Solution

Conclusion

Desertification, as a complex problem, is difficult and cannot be solved in one project. There is no «universal remedy» able to eliminate it completely. There should be rather a range of measures as complex as the problem itself. Nevertheless, some steps can prove to be effective, and the use of Prosopis Juliflora can be a reasonable option.