A survey of flora in the garden infront of admin block of Punjab university was conducted for plant diversity during period of December,2012 to January,2013.All the plants were enlisted and photographed. The information about their general description, habitat, mode of propagation, reproduction and economical uses was searched, collected and discussed. Introduction:
Plant diversity refers to the variety of plants that exist in this world. (Henry,2005)Plants are fundamental to life providing basic and immediate needs of humans for food and shelter and acting as an essential component of biosphere maintaining life on planet. All modern terrestrial plants are the descendants of algae that adapted to a terrestrial habitat roughly 500 million years ago. Compared to water,land is an erratic habitat where temperature and moisture availability may change abruptly and dramatically. There are four major groups that evolved in the following
1. Bryophytes; which include the mosses
2. Seedless vascular plants; which include the ferns
3. Gymnosperms; many of which are also called conifers
4. Angiosperms; the ‘flowering’ plants, which now
Diversity within a population of plants of the same species may be considered a primary level of variation. The factors determining diversity within species are also being better defined by use of DNA analysis method. Plants and plant diversity contribute directly and indirectly to the enrichment of life experiences for humans. The role of plants in the food chain is dominant for all animal life. Plant diversity is a key contributor to environmental sustainability on a global scale. Studies of species richness demonstrate the greater productivity of more diverse plant communities. The mechanisms that promote the coexistence of large numbers of species may include the ability of competitors to thrive at different times and places (Clark and McLauchlan, 2003). The greatest social use of plants probably relates to their use as ornamentals. Ornamental plants often reflect social status or identity. Foods from some plants have a social value extending beyond that contributed by their nutritional values. The following is an excerpt of the ‘Introduction’written by V.H.Heywood and S.D.Davis, which appears in each of three printed volumes of centers of plant diversity. The diversity of plant life is an essential underpinning of most of our terrestrial ecosystems. Humans and most other animals are almost totally dependent on plants, directly or indirectly, as a source of energy through their ability to convert the sun's energy through photosynthesis. Worldwide tens of thousands of species of higher plants, and several hundred lower plants, are currently used by humans for a wide diversity of purposes as food, fuel, fiber, oil, herbs, spices, industrial crops and as forage and fodder for domesticated animals. In the tropics alone it has been estimated that 25,000-30,000 species are in use (Heywood 1992) and up to 25,000 species have been used in traditional medicines. In addition, many thousands of species are grown as ornamentals in parks, public and private gardens, as street trees and for shade and shelter. Another important role of plant life is the provision of ecosystem services the protection of watersheds, stabilization of slopes, improvement of soils, moderation of climate and the provision of a habitat for much of our wild fauna. While it is generally accepted today that the conservation of all biodiversity should be our goal, especially through the preservation and sustainable use of natural habitats, this is an ideal that is unlikely to be...