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M.Sc., BOTANY ECOLOGY and TOXICOLOGY (MBO 33) STUDY MATERIALS

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M.Sc., BOTANY ECOLOGY and TOXICOLOGY (MBO 33) STUDY MATERIALS M.Sc., BOTANY ECOLOGY AND TOXICOLOGY (MBO 33) STUDY MATERIALS What is Ecology? Ecology is a branch of biology concerned with understanding how organisms relate with each other and their environment. This branch of biology mainly deals with the relationships between the organisms, their relationships among each other, their relationships towards the shared resources, their relationships with the space they share, and even their relationships with the non-living aspects in the environment. In understanding the given relationship, ecology encompasses aspects such as population growth, competition, symbiotic ecologic relationships (mutualism), trophic relations (energy transfer from one section of the food chain to the next), biodiversity, migration and physical environment interactions. Because ecology includes all the living organisms on earth and their physical as well as chemical surroundings, it is divided into several categories which bring about different types of ecology as discussed below: An example of ecology is the study of wetlands. Ecology is defined as the branch of science that studies how people or organisms relate to each other and their environment. An example of ecology is studying the food chain in a wetlands area. Level of Ecology The four main levels of study in ecology are the organism, population, community, and ecosystem. Branches of Ecology 1.Terrestrial Ecology Terrestrial ecology is a branch of ecology that deals with the study of land organisms and how they interact with each other and adapt to their environment. Aside from that, the diversity and distribution of different organisms in various terrestrial habitats are also being focused on. Terrestrial ecology has a wide variety of applications like resources management, and in the long run, be effective for conservation measures. Additionally, soil properties like moisture, pH, nutrient and chemical content, and soil type may be studied. 2.Aquatic Ecology Basically the opposite of terrestrial ecology, aquatic ecology deals with the study of the ecosystems found in bodies of water, be it the marine, freshwater, or the estuarine. Aquatic ecology focuses on the interactions among living organisms in a particular aquatic habitat which can directly affect various factors in the ecosystem. Such factors include competition for food and predation, temperature, nutrient concentration, and oxygen demand. 3.Microbial Ecology Microbial ecology focuses on the study of how communities of microorganisms establish themselves on abiotic substrates and how such organizations enable them to interact with each other. The scope of microbial ecology is quite huge as it can cover the vast micro-flora in animal guts, the seemingly simple yet actually genotypically complicated bacterial communities called the biofilms, and the complex relationship between prokaryotes and eukaryotes that somehow led to their divergence. 4.Systems Ecology Systems ecology is a branch of ecology that tackles various abiotic factors like energy budget allocation and physical processes such as carbon cycle and biogeochemical cycles. This branch of ecology is distinctive because it integrates other scientific disciplines like applied mathematics and computer systems to study and predict structures and function in a given ecosystem. 5.Taxonomic Ecology Basically, taxonomic ecology is a new concept in this field. The use of taxonomic data is highly important as it improves the study of the ecosystems by helping identify key organisms present in that area. Aside from that, this branch of ecology helps in the easier classification of organisms, whether each act accordingly or antagonistically with each other in the community level. 6.Evolutionary Ecology Evolutionary ecology merges the two scientific studies of evolution and ecology and focuses on the the physical and genetic changes that occurred among organisms and how such modifications were affected by ecological factors. Basically, it also considers the effect of forces like competition, predation, parasitism, and mutualism in the evolution of individual species, in a population, or in the entire community. 7.Population Ecology As its name suggests, population ecology deals with the study of population structures and dynamics, rather than looking at the individual behavioral patterns of living organisms. Population ecology studies the various factors that affect population size, density, dispersion modes, and growth rate and mortality rate. 8.Community Ecology It deals with how community structure is modified by interactions among living organisms. Ecology community is made up of two or more populations of different species living in a particular geographic area. 9.Behavioral Ecology The next branch of ecology, behavioral ecology, integrates the study of the interaction between survival value to the behavior of organisms and their offspring. Interestingly, it somehow related to evolutionary as it examines how an organism changes its behavior to ensure survival and perpetuation. At present, this branch of ecology attempts to find the link between an animal’s behavior to its environmental adaptation and reproductive success. 10.Conservation Ecology Conservation ecology, as its name suggests, studies the management of biodiversity through conservation and restoration methods. This branch of ecology had just recently evolved to address the decreasing biodiversity and deteriorating natural resources in the planet. This branch is interdisciplinary and utilizes principles from genetics, biogeography, population biology, environmental ethics, and law to help in ensuring the conservation of species and their habitats. 11.Applied Ecology Bringing together all the concepts and principles of ecology, applied ecology aims to apply these significant knowledge, findings, and technological advances to understand real world situations and to address practical human problems. Applied ecology includes applications like management of wildlife and natural resources, epidemiology, and even natural disaster risk reduction and management. The scope of applied ecology is huge and encompasses the fields of biotechnology, ecology, to study how anthropogenic activities affect not only micro-systems but the biosphere as well. 12. Global Ecology (Biosphere) The global ecology is principally important in understanding all the ecosystems affecting the entire globe. This includes all the different biomes, with considerations of aspects such as climate and other environmental geography. It means, global ecology takes into account the whole world’s biosphere while considering all living organisms from the microscopic to higher lifeforms, the environments they leave in, the interactions that they have with each other, the influences that their environments have on these interactions and vice versa, and finally, how they are all interconnected under the common ground that they all share a single planet – the Earth. 13.Landscape Ecology It deals with the exchange of energy, materials, organisms, and other products of ecosystems. Landscape ecology throws light on the role of human impacts on the landscape structures and functions. 14.Ecosystem Ecology It deals with the entire ecosystem, including the study of living and non-living components and their relationship with the environment. This science research how ecosystems work, their interactions, etc. 15.Molecular Ecology The study of ecology focuses on the production of proteins and how these proteins affect the organisms and their environment. This happens at the molecular level. DNA forms the proteins that interact with each other and the environment. These interactions give rise to some complex organisms. 16.Organismal Ecology Organismal ecology is the study of an individual organism’s behaviour, morphology, physiology, etc. in response to environmental challenges. It looks at how individual organisms interact with biotic and abiotic components. Ecologists research how organisms are adapted to these non-living and living components of their surroundings. Individual species are related to various adaptations like physiological adaptation, morphological adaptation, and behavioural adaptation. Importance of Ecology The study of ecology is important in ensuring people understand the impact of their actions on the life of the planet as well as on each other. Here are the reasons why ecology is important: 1. It helps in environmental conservation Ecology allows us to understand the effects our actions have on our environment. With this information, it helps guide conservation efforts by first showing the primary means by which the problems we experience within our environment begin and by following this identification process, it shows us where our efforts would have the biggest effect. Ecology also shows individuals the extent of the damage we cause to the environment and provides predictive models on how bad the damage can get. These indicators instil a sense of urgency among the population, pushing people to actively take part in conservation efforts and ensure the longevity of the planet. 2. Ensures proper resource allocation Ecology equally allows us to see the purpose of each organism in the web of connectivity that makes up the ecosystem. With this knowledge, we are able to ascertain which resources are essential for the survival of the different organisms. This is very fundamental when it comes to assessing the needs of human beings who have the biggest effect on the ecosystem. An example is human dependency
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