Science High Flyer

  Climate change is due to the green house effect, the process by which absorption and emission of infrared radiation by gases in the atmosphere warm the earth’s lower atmosphere and surface. Atmospheric gases such as water vapour, CO 2 , O 3 and CH 4   act like the glass roof of a greenhouse trapping heat which results in the warming of the planet. That is why it is seen to be analogous to that which occurs within green houses. Man’s actions such as the burning of fossil fuels, farming activities and land use changes have all resulted in an increase in these natural gasses. The earth’s surfaces and lower atmosphere are thus warming rapidly. The phenomenon of ‘Global Warming’ was discovered by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896. The physical aspects of global warming, i.e. how and why it occurs and the climate models that are used to predict future changes in the global climate will be dealt with in detail in the nex...

  What is chemical ecology? From studies of the environment’s effect on species (e.g. animal and plants) or the adaptation of species to the environment, evolves a branch of science defied as ecology. Natural products play a fundamental role in the coexistence of species in the ecosystem. Therefore as a result a new branch of biology was developed known as the chemical ecology or ecological chemistry. Chemical ecology describes relationships or interactions between species, which can be related to an effect of naturally produced compounds. Adaptation to the environment Temperature To tolerate low temperatures, it has been found that insects and plants synthesize glycol as antifreeze substances. It is a metabolic adjustment developed by them to freezing (e.g. the green algae Dunaliella parva is reported to accumulate as much as 70% glycol by dry weight). It seems that they have exploited this method long before we applied it to our automobile engines. Increased concentrations...

  Land is one of the most important natural resources on Earth. It refers to the Earth’s terrestrial surface consisting of forests, deserts, human settlement areas and agricultural lands. Land is essential for the provision of food, water and energy for many living systems and is critical to human activity. Land is used spatially (water reservoirs) and temporally (shifting cultivation, dumping grounds) for many purposes. Agriculture and Forestry The two dominant land use activities are agriculture and forestry. Agro-ecosystems cover more than a quarter of the global land area. Agricultural land use depends on the types of crops and agronomics systems which can vary from intensively managed monocultures, to more organic systems involving annual and perennial crops. Over most of the history, including much of the 20 th century, agricultural output has increased primarily bringing more land into production through conversion of forests and natural grasslands. Extractive purposes ...