GENVI NOTES 2.2 LAND Degradation PDF

SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology...

SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology MODULE 2 ENVIRONMENTAL ISSUES AND PROBLEMS UNIT 2 Land Degradation Land is the basis for agriculture and other rural and urban land uses, encompassing soils, climate, vegetation, topography, and other natural resources. It is “a delineable area of the earth’s terrestrial surface, encompassing all attributes of the biosphere immediately above or below this surface including those of the near-surface climate, the soil and terrain forms, the surface hydrology (including shallow lakes, rivers, marshes and swamps), the near-surface sedimentary layers and associated groundwater reserve, the plant and animal populations, the human settlement pattern and physical results of past and present human activities”. Land degradation, on the other hand, is the degradation or destruction of the Earth’s surface and soil, directly or indirectly because of human activities. Causes of land degradation include deforestation, desertification, mining, soil salinization, and urban sprawl. Although natural causes may lead to deforestation, our concentration in this unit would be on anthropogenic activities. A. Deforestation Deforestation is the massive removal of a forest or the clearing of vast forest areas either for lumber source, conversion to agricultural lands, or for urbanization. It is the biggest threat to all forests nationwide. According to the International Union for Conservation of Nature (IUCN), forest degradation occurs when forest ecosystems lose their capacity to provide important goods and services to people and nature. Since 1960, over half of tropical rainforests have been destroyed (IUCN). FIG. 2.2.1 Deforestation https://ucsdnews.ucsd.edu/feature/deforestation-drives-disease-climate-change-and-its-happening-at-a- rapid-rate hsbalangay 1  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology Causes of Deforestation Increase in human population has also increased the demand for food supply, available space, and raw materials for almost every human need. Forests were viewed as areas that can provide all these requirements, thus are very much exploited. 1. Agriculture - conversion of forest into lands into agricultural lands for crops and livestock farming to meet the growing food demands of an exponentially increasing global population 2. Urbanization - clearing of forests to give way to settlements and infrastructure projects such as the building of roads, bridges, railways, airports, and power generation and transmission. 3. Timber Extraction - the global demand for timber has supported illegal and unsustainable logging in various forests of the world - aside from using timber for building settlements, they are also exploited for furniture and paper industries, as well as firewood and charcoal businesses. 4. Anthropogenic Climate Change - climate change has brought severe and frequent droughts, hurricanes and tropical storms, heatwaves, and fires that destroyed forests worldwide - although these are natural phenomena, the change in the normal cycle of the climate is due to human activities 5. Social and Political - Lack of discipline and responsible demand on trades on the part of communities - Failure of the government to implement environmental laws due to incompetence or corruption Effects of Deforestation 1. Anthropogenic Climate Change - Loss of the carbon dioxide absorbing capacity of forests leads to the accumulation of this greenhouse gas in the atmosphere - Increase in greenhouse gases leads to global warming that leads to climate change 2. Soil Erosion and Flooding - roots of plants, especially trees, bind soil particles, preventing them from being washed out during a storm or heavy rains - although soil erosion is a natural phenomenon, deforestation accelerates the process, causing the nutrient rich topsoil to be washed out, leaving behind an unfertile land - The trees themselves act as barriers that slows down the rushing of water as it runs off the land - Without these trees, water will simply rush and flood to low lying areas hsbalangay 2  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology 3. Reduced Air Humidity - Without vegetation, the rate of evapotranspiration is greatly decreased, affecting the normal water cycle - Decrease in evapotranspiration decreases the amount of water vapor in the atmosphere, decreasing condensation, and decreasing rainfall 4. Loss of Habitat and Biodiversity - Destruction of the homes of thousands of species that live in the forest - Leads to a decline in both species richness and species diversity - Numerous species are now extinct, and more are in the endangered species list Dealing with Deforestation 1. Reforestation and Afforestation - Reforestation is the process of restoring forests by planting the same tree species that are native to that specific forest - Afforestation involves planting trees in areas that were never forests, converting (not restoring) an area into a forest 2. Forest Landscape Restoration (FLR) - Planting trees is not enough to restore forests, so IUCN has collaborated with FLR enthusiasts to bring people together to identify and implement the most appropriate restoration interventions in a landscape - It includes multiple activities like managing natural regeneration, agroforestry, protect wildlife reserves, mange plantations, erosion control, and improved land management by addresses the underlying drivers of forest loss 3. The Power of the Marketplace - Companies can make an impact by introducing and implementing “zero deforestation” policies that clean up their supply chains - set ambitious targets to maximize the use of recycled wood, pulp, paper and fiber in their products - For the non-recycled products bought, they should ensure that any virgin fiber used has transparent, credible assurances that it was sourced in a legal way that respects principles of environmental and social responsibility 4. Changing the Politics - The National Integrated Protected Areas System Act of 1992 (Republic Act No. 7586) or known as the NIPAS Act states that “to secure for the Filipino people of present and future generations the perpetual existence of all native plants and animals through the establishment of a comprehensive system of integrated protected areas within the classification of national park as provided for in the Constitution” (Section 2, NIPAS Act) - provides the legal framework for the establishment and management of protected areas (PAs) in the Philippines, and that the use and enjoyment of these protected areas must be consistent with the principles of biological diversity and sustainable development hsbalangay 3  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology 5. Standing with Indigenous Peoples - Indigenous peoples call the forests their homes and have shown cultures indicative of sustainable forest management - This shows that they are the best protectors of forests, thus the best way to save forests is to recognize the claims of indigenous peoples to their forest territories B. Desertification Desertification is another form of land degradation that occurs in arid, semi-arid, and dry sub-humid areas. It does NOT mean literally converting a land to a desert, but rather refers to the conversion of a productive land to an unproductive barren land. It is characterized by the loss of soil moisture and nutrient rich topsoil to the point where the land loses its productivity or ability to produce vegetation. FIG. 2.2.2. Desertification https://ourworld.unu.edu/en/desertification-crisis-affecting-168-countries-worldwide-study-shows Causes of Desertification 1. Overgrazing - This is the major cause of desertification worldwide - occurs when too many animals graze for too long, exceeding the ability of a grassland area to support them - overgrazed lands have grasses that were eaten down to its soil level, exposing the topsoil to elements of erosion hsbalangay 4  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology 2. Anthropogenic Climate Change - Severe drought and moisture loss kill vegetation and prevents any other from thriving on an extremely dry land 3. Deforestation - Removal of trees means removal of the forest cover, exposing forest soil to direct sunlight - Increasing soil temperature also increases the rate of evaporation, making the land very dry - Soil erosion due to deforestation removes the nutrient rich topsoil, converting a productive land to a barren land 4. Unsustainable Farming Methods - Failure to employ crop rotation depletes the topsoil of nutrients, degrading the soil - Over tilling the soil dislodges soil particles, making them vulnerable to erosion and eventually lose soil nutrients and ability to store water Overuse of chemical fertilizers and pesticides alters the chemical balance of the soil, making it in hospitable for plant growth 5. Overuse of Groundwater - Excessive pumping of ground water for human consumption dries up the ground water reservoir, depriving vegetation of much needed water supply Effects of Desertification 1. Decrease in Crop Yield - with the much-needed food for the growing population, losing viable agricultural lands to desertification poses as a major problem that could lead to food shortage 2. Loss of Habitat and Biodiversity - desertification makes it impossible for plants and animals to survive and sustain their population - it is the decline in population that makes species vulnerable to extinction 3. Migration and Overpopulation - Loss of both food supply and livelihood drives people to leave and migrate to more productive areas, which in the end will be overpopulated by the influx of migrants Dealing with Desertification 1. Rotational Grazing - Involves dividing an entire Pasteur to sub-pastures or paddocks - Cattle grazing in these paddocks are done so by schedule, allowing time for Pasteur plants to rest, grow, and recover before being grazed again hsbalangay 5  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology FIG. 2.2.3. Conceptual Pathway of FIG 2.2.4. Rotational Grazing Rangeland Desertification https://prairieecologist.com/2017/11/21/open-gate- https://www.researchgate.net/figure/Conceptual- rotational-grazing/ pathway-of-rangeland-desertification-process-from- 2. Better Farming Methods Thurow-1991_fig2_8243584 - Practice of crop rotations, use of organic fertilizers, and improved tilling methods 3. Reforestation - In areas that were subjected to deforestation, reforestation efforts should take precedence 4. Sustainable use of Ground Water - Using just enough water to prevent depletion and allowing ground water to be replenished 5. Decrease Greenhouse Gas emissions - Curb the effects of global warming and climate change by decreasing and managing activities involving greenhouse gas emissions hsbalangay 6  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology C. Other Types of Land Degradation Soil Salinization and Waterlogging Irrigating crops over several seasons causes the accumulation of salts in the upper layers of the soil. Irrigation water contains various dissolved salts picked up as water flows over or through rock and soil. This is called soil salinization. Water logging starts by attempting to wash the salts out of the topsoil by pumping more water. Accumulation of saline water underground, gradually saturates the soil and results to the damage and killing of plants as saline water surrounds the deep root. The hypertonic environment of the roots prevents water from osmotically diffusing into the roots, dehydrating the plant. This then leads to decreased plant growth, reproduction, and eventually death. This problem can be addressed with the use of less water for irrigation, pumping water in unlined ditches, or spraying it across large areas of the fields with the use of use of sprinklers or drip irrigation. Installation of drainage systems can prevent waterlogging. FIG. 2.2.5. Soil Salinization and Waterlogging https://link.springer.com/chapter/10.1007/978-3-319-96190-31 hsbalangay 7  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology Mining This is the process of extracting precious minerals and other geological materials from the earth. Surface mining involves stripping the land of its vegetation and soil, resulting to severe erosion. Mountain top removal for coal mining dumps huge amounts of waste rock and dirt in the valleys below the mountain, destroying forests and streams, contamination the freshwater water supply. Underground mining involves the digging of shafts and tunnels, often with the aid of explosives. This could trigger the formation of sinkholes. FIG. 2.2.6. Types of Mining Methods https://www.nap.edu/read/11977/chapter/6 Mining is one form of land degradation that requires strict monitoring and full compliance with mining laws and regulations. Non-compliance should result to closure of the mining activity and cancellation of all permits. Shut-down mines should also be reclaimed for restoration. Urban Sprawl This refers to the rapid expansion of a city into the countryside around the city. This expansion and growth results in the building of housing or suburbs and associated commercial buildings on the boundary of a larger town. Many of these suburbs are usually built on lands previously used for food production. Urban sprawl leads to loss and fragmentation of habitat due to the building of new settlements and infrastructure projects. Increase in energy demand increases the use of fossil hsbalangay 8  SAINT LOUIS UNIVERSITY SCHOOL OF NURSING, ALLIED HEALTH, AND BIOLOGICAL SCIENCES SAINT Department LOUIS UNIVERSITY of Biology SCHOOL OF NATURAL SCIENCES Department of Biology fuels, that increase greenhouse gases and lead to global warming. Sustainable development should be practiced as communities are built. Management strategies should be put in place to direct urban growth. To reduce the use of automobiles, residential and commercial areas should be built around mass transit networks, called transit villages. Ecovillages can also be developed wherein communities actively participate in re- greening movements and maintain ecological sustainability. FIG. 2.2.7. Urban Sprawl https://www.britannica.com/topic/suburb hsbalangay 9