Campus landscape
By Adegbenga Sefiu Kaka
Being an address delivered by Senator Adegbenga Sefiu Kaka at the tree planting programme tagged: "FUTA Greening 2013" held at the Federal University of Technology, Akure, Ondo State, Nigeria.
The importance of green vegetation in our environment is multi-dimensional and its benefits are unquantifiable. In many cases, people do not understand the importance of vegetation until they are gone, when their water supplies disappear or their soil erodes quickly or the local climate changes.
Vegetation in our environment provides benefits such as erosion control, flood prevention, mitigation of droughts, moderation of weather extremes and their impacts, maintenance of biodiversity, filtration of pollutants from water (mitigation of the effects of salinity) and air (removal of carbon dioxide from the atmosphere), preservation of soils and renewal of nutrients, production of food and fibre for human use, provision of shade and aesthetic appeal, opportunities for recreation, etc.
Aesthetic Benefits
This is one benefit which readily comes to mind; a beautifully landscaped environment is a well suited place for living, learning, meditation, therapy, recreation, and overall human health and well-being. Campuses all over the world, including our Obafemi Awolowo University, prides in the beauty of its environment. Carefully landscaped and ‘manicured’ lawns and gardens, and trees properly situated maintained and trimmed makes for a qualitative learning environment.
Health and Social benefits
Tending the garden or gardening is a way to exercise; workers with a view of natural elements, such as trees and flowers, have been found to experience less job pressure, were more satisfied with their jobs and reported fewer ailments and headaches than those who had no outside view. Playtime and recreation in outdoor green spaces can have a positive impact on children and adults.
There are also food, medicinal, and social products which are fundamental to developing and maintaining human health and well-being that are directly produced from grasses, shrubs, and trees planted in our surroundings, for example, lemon grass, Apples from Apple trees, Ewuro (Vernonia amygdalina), Dongoyaro leaves (Azadirachta indica), fibre from palm trees, to mention but a few. Mango trees while providing shades and aesthetic benefits also produces fruits for human consumption.
Environmental Benefits
Erosion Control: The roots of plants (grass, shrubs and trees) serve as an extensive net that holds the soil in place, thereby preventing excessive erosion of the soil and its nutrients. The roots also absorb water from the soil, allowing the trees to act as natural storage tanks of freshwater, and slowing the loss of rainwater from the ecosystem through runoff. Some of the water absorbed by trees is released into the air as water vapour through the leaves; this restores moisture to the atmosphere and helps maintain the water cycle in the local environment.
Moreover, by controlling the flow of surface water and reducing the runoff of soil, plants can also help mitigate the effects of extreme weather events. This reduces the occurrence of floods and mudslides, particularly in areas susceptible to disasters, such as coastal areas and mountainous regions. Plants can also reduce the risk of droughts by retaining water in the local environment and cooling local temperatures by shading the soil.
Pollution Control: Trees, shrubs, turf, and groundcovers trap and filter dust and other pollutants out of rainwater. Plants benefit from the nutrients in this particulate matter and prevent it from becoming a source of water pollution. Planting landscape buffers can reduce the flow of sediments and pollutants into nearby bodies of water. As surface water runoff moves through the vegetation buffer, sediments and pollutants are filtered out. In general, the wider the plant buffer, the greater the pollutant removing capacity.
By absorbing minerals and chemicals through their roots, trees can remove pollution from the soil and from the freshwater that runs through it, such as streams used for drinking water. Trees can therefore serve as a natural water purification system, cleaning the water of the ecosystem and providing safe water for human consumption.
Plants improve air quality. “One tree can remove 12kg of carbon dioxide from the atmosphere annually, equalling 17,700km of car emissions. Landscape plants, including shrubs and turf, remove smoke, dust, and other pollutants from the air. One study showed that 1 acre of trees has the ability to remove 13 tons of particles and gases annually.” An average tree absorbs 12kg of carbon dioxide from the air each year and releases enough oxygen each day to supply a family of four.
By the process of photosynthesis, trees capture and store carbon dioxide from the atmosphere, helping to reduce quantities of this greenhouse gas and mitigating the effects of climate change.
It has been proven that plants help to remove organic volatile compounds from indoor air. "Low levels of chemicals such as carbon monoxide and formaldehyde can be removed from indoor environments by plant leaves alone, while higher concentrations of numerous toxic chemicals can be removed by filtering indoor air through the plant roots surrounded by activated carbon. The carbon absorbs large quantities of toxic chemicals and retains them until the plant roots and associated microorganisms degrade and assimilate these chemicals."
Plants are useful in moderating the temperature effects of solar and infrared radiation, thus increasing environmental comfort levels. This is highly noticeable in suburban and rural areas. Plants regulate local temperature by providing shade, cooling both the soil and the air below the upper branches. Perhaps most importantly plants provide natural habitat for other life forms, as a home and a food source. In these and many other ways, plants stabilise and maintain the soil, biodiversity, and climate of the environment.
Properly selected and placed plantings absorb sound waves, and can significantly reduce unwanted ‘noise pollution’.
Economic Benefits
Employment: Landscape Architects and Horticulturists, individuals, as well as businesses are involved in the intensive cultivation of plants and ornamentals for the beautification of buildings, structures, and facilities. This provides employment for plant breeders, horticulturists, gardeners, landscapers, labourers, gardening machinery and tools manufacturers. There are also related services like plant conservation, landscape restoration, landscape and garden design/construction/maintenance, horticultural therapy, and much more which provides employment for people.
All of these benefits – aesthetics, socio-economic, erosion control, maintenance of the water cycle, temperature regulation, habitat for biodiversity, water purification, climate regulation, mitigation of extreme weather events, and enrichment of the soil - demonstrate the value of keeping and maintaining grass, shrubs and trees in our environment.
Perhaps the Nigeria paradox of enormous landscape, staggering revenue from crude oil, about the cheapest labour (skilled and unskilled) in the world and yet convulsive unemployment situation, can be better resolved by encouraging all and sundry to go green for various benefits highlighted above.
It is on this note that I humbly and gratefully accepted to be the FUTA-GREEN AMBASSADOR for the year 2013 to the glory of God and benefit of mankind.
* Kaka represents Ogun East Senatorial District in Nigeria's Upper Legislative Chamber - The Senate.