Introduction

DefinitionEnvironmental Science – an interdisciplinary

field that integrates physical and biological sciences, to the study of the environment, and the solution of environmental problems. It provides an integrated, quantitative, and interdisciplinary approach to the study of environmental systems.

EcologyEcology is the study of the relationships

between an organism and its environment. Ecologists might investigate the relationship between a population of organisms and some physical characteristic of their environment, such as concentration of a chemical; or they might investigate the interaction between a two populations of different organisms through some symbiotic or competitive relationship

PopulationA group of individuals of the same species

living in a particular geographic area.

CommunityConsists of all the organisms of all the species

that inhabit a particular area

EcosystemConsists of all the abiotic factors in addition to

the entire community of species that exist in that area

Components of an Ecosystem1. Biotic – the living components; predators,

preys, parasites, competitors2. Abiotic – non living chemical and physical

factors such as temperature, light, water and nutrients. It also includes soil, altitude, climate, latitude

Types of Ecology1. Ecosystem ecology – examines the energy

flow and cycling of chemicals among the various abiotic and biotic components

2. Landscape ecology – deals with the array of ecosystems and their arrangement in a geographic region

3. Population ecology – examines factors that affect population size and composition

Classification of Living ThingsKingdom – the highest rank; either plantae or animaliaPhylum or phyla can be thought of as grouping

organisms based on general specialization of body plan as well as developmental or internal organizations. The best known animal phyla are the Mollusca, Porifera, Cnidaria, Platyhelminthes, 

Nematoda, Annelida, Arthropoda, Echinodermata and Chordata, the phylum to which humans belong, along with all other vertebrate species

Classification of Living ThingsExample: dogKingdom animaliaPhylum chordataClass mammaliaOrder carnivoraFamily canidaeGenus canisSpecies familiarisScientific name: canis familiaris

Hierarchy of LifeAtoms

moleculesorganelles

celltissue

organsorganism

Hierarchy of LifeOrganism

populationcommunity

ecosystembiosphere

BiosphereBiosphere is the sum of all ecosystems

including all living things from plants, animals and all microscopic forms, including bacteria and viruses.

It is referred to as the zone of life on Earth. It includes land, water and air in which organisms survive.

Aquatic BiomesAquatic Biomes may be:1.Marine – with an average salinity of 3%2.Freshwater – with an average salinity of 1%3.Brackish – combination of marine and

freshwater

Terrestrial Biomes