PhD Theses (SACON)

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Author: search.filters.author.Azeez, P AEnd date: 2009

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    A study of the ecology of select species of weeds in different vegetation types of Nilgiri Biosphere Reserve
    (SACON, 2000) Mahajan, Maya V; Azeez, P A
    Invasion by weedy species of plants has serious impact on natural and managed ecosystems. Weedy species invade agricultural lands, fallow lands, roadsides, disturbed forests and plantations. Invasion by such species modifies the ecosystem structure and function. Invading species may dominate and displace the native vegetation and cause extinction of certain native species, leading to alteration in the original biodiversity of an area. In recent years, biological invasion is being recognised as a serious threat to biodiversity conservation (Pimm and Gulpin 1989, Vitousek et al. 1996). In contrast to studies in agricultural fields, not much attention is given to plant invasion in natural ecosystems. Nevertheless, the colonisation of natural forest ecosystem by weedy species is growing as a threat. In recognition of the threats posed by plant invasions in natural vegetation and realising the scarcity of ecological information on various colonising plant species
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    Air Quality of Coimbatore with Emphasis on Respirable Suspended Particulate Matter
    (SACON, 2002) Mohanraj, R; Azeez, P A
    Particulate matter (PM), a complex mixture of organic and inorganic substances is an ubiquitous air pollutant, contributed by both natural and anthropogenic sources. Ever since the advent of industrial era, anthropogenic sources of PM have been increasing rapidly. Increasing amounts of such potentially harmful particles being emitted into the atmosphere on a global scale has resulted in damage to the health and environment. Recently it is also reported that soot particles have a heating effect to the atmosphere. Such heating effect can have wide implications on various systems of earth including climate. PM in the atmosphere is categorized according to size because of different health impacts from particles of different diameters. PM with diameters of less than 50 pm are generally classified as Total suspended Particulate Matter (TSPM). Particles that are greater than 50 pm in diameter do not remain in the atmosphere for appreciable lengths of time and present no health risk. Particulates with a diameter less than 10 pm defined as PM 10 or Respirable Suspended Particulate Matter (RSPM), enter the respiratory system and may become lodged in the alveoli resulting in wide range health effects including cancer and heart failures. PM 10 has the potential to travel long distances and cause cumulative effects. Other hazardous air pollutants may adhere to these particles, increasing their toxicity. These particles on wet and dry deposition are known to pollute local, regional and global land and water resources.