Phases in Cultural and Technical Development of Human Activity - Assignment Example

Question The three main phases in major cultural and technical development are divided into hunting and gathering,plant cultivation, animal keeping and metal working as well as modern urban and industrial society. The first phase of hunting and gathering describes human beings as an evolving species. For instance, human activity and technological advancement have been the oldest records of human development. Pebble tools were crude tools that consisted of a pebble stone chopped into a rough cutting edge on one end and have been discovered in Africa. The first phase is hunting and gathering (Goudie). The Stone Age advanced to be more diverse and altered by progressive use of the tool. Besides, there is certainly a lot of evidence for the use of wood throughout the Paleolithic Age. Wood was used for making ladders, lighting fire, as a pigment (charcoal), drying wood and as digging sticks. One of the distinguishing features of the Paleolithic age was building of shelters and use of clothing which made habitation in unfriendly environment much easier. This became a permanent feature of man during this period. Secondly, one of the features that distinguished the early society that distinguished human from the other surviving non-human primates was their ostensibly omnivorous diet. Furthermore, humans had advanced communication skills by a way of coherent speech. Through communication and usage of words as symbols, hominids cold organize themselves into a culture with an identity. At the early stages of settlement, human beings discovered fire and its usage. Moreover, the early society diffused seeds and nuts onto the vegetation for plantation activities. Interestingly, through hunting and gathering activities, human’s occupation had a dramatic effect on the animal population causing migration and even extinction of some great mammalian species. It can be argued that the low population densities of the hunters, gatherers and scavenger human groups were attributed to the introduction of pastoralism and agriculture (Goudie). The second phase is plant cultivation, animal keeping and metal working. Historically, humans began to domesticate animals and to gather food plants rather than just hunt animals. Although it is now recognized that some hunters and gathers had significant leisure, there is no doubt that through the controlled breeding of animals and plants humans were able to develop a more expandable and a reliable source of food; thereby, creating a solid and secure basis for cultural advancement. It opened doors fro humans to embrace civilization and urban revolution’ of childe (Goudie). In fact, Issac opines that domestication is the single most important intervention man had made in his environment (Goudie). The important developments in agriculture included invention of the plough, irrigation and adoption of riverine system. In terms of importance, irrigation and adoption of riverine agriculture were the most significant advancements. The plough was particularly important in agriculture. It was the first application of animal power to the mechanization of agriculture. In close connection, was the use of the cart that permitted more intensive farming and transportation of farm products. Moreover, the production of textiles from animal fibers enabled foreign exchange with humans in areas where arable farming was not the primary form of land use. Arguably, domestication of animals and cultivation of plants have been the most significant impact of human settlement on the environment. For instance, pastoralism ahs had major effects such as soil erosion that has eliminated hundreds, probably thousands of native prairie herbs and grasses. The extent of the spread of agriculture has transformed land cover on a global scale. Significantly, this may reduce stability in the ecosystem. Additionally, mining of ores and the smelting of metals was a significant technological advancement of humans (Goudie). Lastly, modern urban and industrial society has had an impact on the cultural and technological development of humans. Modern science and modern medicine have compounded these effects, causing an acceleration of population increase even in non-industrial societies. Urbanization has impact a lot, and it is now recognized that large cities have their own environmental problems effects. Moreover, the invention of the steam engine in the last eighteen century and the internal combustion engine in the late nineteenth century massively increased human access to energy and lessened human dependence on animals, water and wind power (Goudie). As civilization took effect, there was a resultant increase in human population, world economy, energy use, fresh water use. Consequently, humans used more energy, more fish reducing the forest and woodland area by about 20%. This accounted for perhaps half the net deforestation in the world’s history. For this reason, people tend to believe that human domination of the planet was detrimental especially with the development of nuclear reactors citing events of Second World War. Furthermore, environmental issues that were once locally defined have become a regional problem. Besides, the expanding population and an increase in per capita consumption have increased the complexity, magnitude, and frequency of environmental impact. Therefore, we can witness pollution and the escalating trajectory of environmental transformation has resulted into global environmental change (Goudie). The contributing factors include cumulative global change and systemic global change. Importantly, the development of technology, has allowed more efficiently use of energy and the ever‐growing demand for Energy is at the cause of many modern environment problems. Although, technological advancement promised to solve dome of these newer ones were created. Question 2 Human activities have resulted in secondary salinization in drylands in a number of ways. In table 4.1 these mechanisms are grouped into five main categories; irrigation salinity; urban salinity; dryland salinity; coastal zone salinity and salinity brought about by interbasin water transfers. Firstly, irrigation salinity has been due to the fact that in recent decades there has been a rapid and significant spread of irrigation across nations the world (Table 4.3). The use of large amounts of irrigation of water results into a rise in groundwater levels. Consequently, high air temperatures lead to rapid evaporation of the water; thereafter, salts build up in the soil (Figure4.1). An example is the extension of irrigation in the Indus valley of Pakistan through large canals resulting into widespread salinization of the soils and waterlogging. Interestingly, the white efflorescence of salt in the irrigation fields had been named ‘a satanic mockery of snow’ (Figure 4.2). The mechanisms of salinization include a vast array of means. Firstly, the application of irrigation water to the soil causes a rise in the water table. It subsequently becomes near enough to the ground surface; therefore, capillary rise and subsequent evaporative concentration occurs. Secondly, many irrigation schemes in areas of high temperatures and high rates of evaporation face the fact that water applied over the soil surface is easily concentrated in terms of any dissolved salts contained therein. Thirdly, the construction of large dams and barrages creates massive water bodies which encourage further evaporation leading to the concentration of the dissolved salts (Goudie). Secondly, vegetation clearance is an important cause of dry land salinity. The clearance of native forest reduces interception and evapotranspiration losses that allow a greater penetration of rain water into deeper soil layers. Consequently, ground water levels rise creating conditions for seepage of saline water into low-lying areas. Thirdly, urban salinity attributed to great growth in urban areas in dry land areas. Urbanization affects the amount of moisture lost by evapotranspiration. Fourthly, interbasin water transfers are a reason for the increase in levels of salinity due to the changing state of water bodies. This is exemplified by the effects of interbasin water transfers is the desiccation of the Owens Lake in California (Goudie). Another example is the diversion of water basins to feed the unquenchable demands of Los Angeles resulting in the lake drying out. This has caused saline dust storms to become an increasingly serious issue. Lastly, coastal zone salinity is due to the spread of saline conditions through the incursion of seawater attributed to over pumping of ground water. Saltwater displaces less saline groundwater by a principle known as Ghyben-Herzbeg (Goudie). Arguably, the cause is not necessarily solely ground water overpumping, but may also be attributed to changes in water levels. Besides, fresh water recharge by the construction of the Aswan High dam is a contributing factor. The Ghyben-Herzberg relationship describes that fact that since freshwater has a lower density than saltwater, a column of seawater can support a column of fresh water with a density approximately 2.5 % higher than it (Goudie) Question 3 Human impact on the environment begins with vegetation, for humankind has possibly had a greater influence on plant life than any of the other life forms of the environment. Salinity is a factor of the natural resources. Therefore, increasing salinity has a whole series of consequences that includes but not limited to a reduction in the availability of potable water, reduction in crop yields and deterioration in soil structure. The death of vegetation in areas of saline patched soils due to both to poor soil structure and toxicity, enables a bare ground that becomes a focal point for potential erosion by wind and water. Furthermore, the most serious impact of salinization is on plant growth. It is attributed to effect on soil structure, but more importantly, through direct toxicity (Goudie) . Additionally, the phenomenon is described as the osmotic movement of the water from the plant cell towards the more concentrated soil solution. The cell dies and the plant succumbs resulting in reduction in crop yields. However, toxicity effect varies with different plants and different salts. For instance, sodium carbonate may damage plants by, by creating highly alkaline soil conditions causing a direct caustic effect, whiles high nitrate promotes undesirable vegetative growth in grapes or sugar beets at the expense of sugar content. Boron is particularly injurious to many crop plants at solution concentrations exceeding 1 or 2ppm. In essence, poor structure and toxicity makes soil almost impermeable to water and unfavorable for root development. Nonetheless, salinization affects vegetation growth through changes in osmotic pressure impeding growth of plants as plants cannot absorb moisture (Goudie). Question 4 Table 4.9, shows that the relative of erosion effects for three main types of environment which include forest or ungrazed thicket, barren soil and crop collected from data from tropical Africa. It is widely known that deforestation and agriculture have an impact on soil erosion. Forests are protective of the direct effects of rainfall and erosion rates on soil. Canopies reduce the impact of raindrops on the soil through reducing their velocity; consequently, their kinetic energy. Generally, canopies decrease the erosion effects of rainfalls by forming humus in forest soils. Therefore, forest soils have high infiltration capacities. Besides, forest soils have the ability to spread large amounts of water through their fabrics. This is achieved by that they having many macrospores found in the roots by roots (Goudie). Moreover, the organic material is an important cementing agent that forms large water-stable soil aggregates. Additionally, earthworms also assist by producing large aggregates. Importantly, deep-rooted trees stabilize steep slopes by buttressing the total shear strength of the soils. Arguably, the rate of soil erosion would be high if the soil is left bare. Nevertheless, the method of plowing, the nature of the crop, the time of planting and size of the fields, will all impact the severity of erosion. Lately, techniques have been introduced which enable rates of erosion on slopes to be determined over a lengthy period of time through dendrochronological techniques. It works by dating the time of root exposure for particular suitable species of tree Rainfall does not necessarily affect soil erosion; however, slope and run off does (Goudie). Additionally, when forests are removed, loss of soil as well as mass movements increases in frequency and amplitude. The type of soil erosion that occurs when forest are removed is equated to surface stripping and mass movements such as debris avalanches, mudflows and landslides. Besides road construction and digging drainage ditches have been shown to accelerate soil erosion while sediment loads increase reservoir pollution. In the tropical and semi arid areas, soil; erosion is particularly serious due to deforestation and agricultural practice (Goudie). Question 5 Through the building of roads, grazing cattle and watering crops, human beings constantly change the environment. The weather has been modified through cloud seeding although there has not been any scientific proof that rain or snow would not have occurred in a natural way. The program indicates how migration in the Sahle changed regional climate. Moreover, it studies the tomorrow-be-damned policy regarding water usage in Arizona and examines the drastic miscarriage of well intentioned interventions in Central Asia where interventions to irrigate the desert resulted into the worst ever climatic disaster recorded in the history of the Soviet Union, in particular, the drying up of the Aral Sea which was arguably one of the world’s fourth lake. The 26 minute program shows how this catastrophe occured and its consequences to the population, the climate and the physical geography of the region (Granada International Media ). In one of the scenes, Airplanes are seen spraying the clouds with microscopic particles of silver iodide in an attempt to induce rain or snowfall aiming to defuse storms and to relieve droughts. In particular, the United States seeded clouds over the region of Ho Chi Minh Trail in an effort to create muddy conditions during the Vietnam War. There have been many questions surrounding the effectiveness and consequences of seeding clouds. Moreover, humans have involuntarily modified weather for a number of years. For instance, building modern cities is reason enough to change the local climates. Cities have changed water runoff; thereby, increasing local temperatures influencing humidity and cloud formation in a manner that intensifies storm systems (Granada International Media ). In a deeper insight, human activities have the potential of discouraging rainfall. During the 1970s and 1980s, a succession of droughts resulted in migrations and overgrazing in the regions of Sahel in Africa. A theory argues that loss of vegetation due to overgrazing contributes to more drought. In comparison, Tucson, Arizona has a similar type of climate as the drought-stricken areas of Africas Sahel region. It is argued that large amounts of water evaporate from golf courses and swimming pools in some desert areas of rich states like in the United States of America (Granada International Media ). Finally, the Soviet Union had developed large scale irrigation projects in an effort to its central Asian republics showcases for agricultural advancement. Consequently, that was the end of the Aral Sea. The death of Aral Sea completely devastated the region’s shipping and fishing industries. Salt storms, threatened regional agriculture and looming climatic disaster set grounds for the collapse of the entire town (Granada International Media ). Salinization results in a reduction in the number of fish and their overall health. Besides, it has altered the weather patterns with preponderance to salt dust storms. As more salt accumulates, there is a reduction in the size of the lake as well a reduction in the depth. Question 6 Land subsidence can only occur under certain geological conditions. For instance, in situations where the deposits involved are majorly composed of soil (sediments) characterized by high initial porosity. Additionally, almost all the subsiding areas are marked by underlying semi-confined/ confined underground water composed of sand/gravel with high permeability and low compressibility. Moreover, they are inter-bedded with layers of clay/silt characterized by low vertical permeability and high compressibility. Nonetheless, ground subsidence can be caused or worsened by humans in a number of ways. Firstly, the transfer of subterranean fluids (such as oil gas, and water) could worsen ground subsidence. Secondly, the removal of solids by underground mining or rather by dissolving solids then removing them in solution is another way of causing ground subsidence. Lastly, disruption of permafrost, compaction or reduction of sediments for purposes of drainage and irrigation is another way. Rarely, subsidence is associated with earthquake activity, or effects on Earth’s crust on large masses of water held behind reservoirs. In essence, liquefaction, formation of sink holes, excessive drainage of aquifers has been attributed to land subsidence. Sink holes could develop after dissolution and collapse in cases where the underlying bedrocks are carbonated. It tales a long period of time with sudden failures attributed to extreme fluctuations of underground soil water levels in periods of prolonged dry and wet seasons. Liquefaction causes compaction and settling of the underground sediments; thereby, lowering the land surface. Therefore, subsidence is a diverse but important aspect of the role played by humans as geomorphologic agents (Goudie). In Mexico City, land subsidence has been associated with excessive drainage of aquifers. Similarly, land subsidence in San Joaquin Valley is associated with pumping of ground water. In Mexico City the aquifers are found 50m below. This is profound in the two very compressible silty-clay beds measuring 25-30m and 5-10m. On the other hand, the aquifers in San Joi Valley are confined or semi-confined below 30-200m. Therefore, withdrawal of water can cause decline in pressure of the aquifer at 10-153m (Goudie). Works cited Goudie, Andrew . The Human Impact on the Natural Environment. London: MIT Press, 2006. Modifying the Weather: The Case of the Man-Made Desert. Dir. Granada International Media. Granada International Media . 2010. Read More