CHAPTER ONE
INTRODUCTION
The conservation of biodiversity is one aspect of environment, which has recently received global attention. Biodiversity refers to the variety and variability among living organisms and the ecological complexes in which they occur (Board on Science and Technology for International Development (BOSTID), 2002. It is a term used to describe the degree of nature’s variety including both the number and frequency of ecosystems, species or genes in a given assemblage. It is essentially synonymous with life on the earth. It is usually considered at three different levels: genetic diversity, specie diversity and ecosystem diversity. Genetic diversity is the sum total of genetic characteristics of individual plants,animals and other living organisms inhabiting the earth. Such characteristics may include rapid growth, high yields, diseases and pests resistance, and environmental adaptation.Specie diversity refers to the variety of living organisms on earth, while ecosystem diversity refers to the variety of habitats, biotic communities and ecological processes in the biosphere as well as the tremendous diversity within ecosystems in terms of habitat differences and the variety of ecological processes.
The concept of agricultural biodiversity or agro-biodiversity as it is sometimes referred could be identified within a macro concept of biodiversity. Agricultural biodiversity is restricted to plants and animals used in commerce or having potential use (Srivastava, Smith and Ferno,2001). It is the diversity of genetic resources (varieties, breeds, species, cultivated, reared or wild) used directly for food and agriculture; the diversity of species that support production(soil biota, pollinators, predators, etc.) and those in the wider environment that support agro-ecosystems (agricultural, pastoral. forest and aquatic), as well as the diversity of agro-ecosystems themselves (Food and Agriculture Organization, 2008).Agro-ecosystems are those ecosystems that are used for agriculture, and comprise poly-cultures, mono-cultures and mixed systems including crop-livestock systems (rice-fish), agro-forestry agro-silvo pastoral systems, aquaculture as well as range lands, pastures and fallow lands (Pimbert, 2009).Agricultural biodiversity is of immense benefit to humanity. Man depends on various livestock and crop species for food, fuel, fibre, medicine, drugs and raw materials for a host of manufacturing technologies and purposes. The productivity of agricultural system is as a result of a continuous alteration of once wild plant and animal germ plasms. Also genetic engineering especially in. the pharmaceutical and food processing industries uses a genetic resources from sources worldwide. Besides these direct values, agricultural bio-diversities arc important parts of the processes that regulate the earth’s atmospheric,climatic, hydro-logic and biochemical cycles
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