Ecology Ecological basics of the environmentalism • Ecology – • Environmental studies – • Environmentalism – env. activism - Ecological basics of the environmentalism • Ecology – the science of the relationships between organisms and their environment in which they live and organisms with each other - non-evaluative, exclusively descriptive - sometimes are environmental studies called ecology (in general) • Environmental studies - addresses the humans’ relationship to the environment - includes both descriptive and normative components - takes evaluation opinions (good X bad) • Environmentalism – env. activism - social movement (ideology) which aims to promote the conclusions of environmental studies in society Ecosystem • dynamic circulation system of living organisms and their environment, where an exchange of matter, energy and information takes place • Ecosystems represent the quality from which human society arose and on which it is existentially dependent • human - an integral part of many ecosystems Ecosystem • dynamic circulation system of living organisms and their environment, where an exchange of matter, energy and information takes place • Ecosystems represent the quality from which human society arose and on which it is existentially dependent • human - an integral part of many ecosystems • humans influence ecosystems and vice versa Ecological stability • the ability of an ecosystem to compensate the changes caused by external factors and to preserve its natural functions and properties • the greater the diversity of the ecosystem = the greater the stability - e.g. monoculture X mixed culture (forest) – pests (e.g. bark beetle) • resistence – • resilience – Ecological stability • the ability of an ecosystem to compensate the changes caused by external factors and to preserve its natural functions and properties • the greater the diversity of the ecosystem = the greater the stability - e.g. monoculture X mixed culture (forest) – pests (e.g. bark beetle) • resistence – the ability of the ecosystem to resist to disruptions • resilience – the ability of the ecosystem to return to its original state after a disruption • both properties act more/less together, but their capacities are limited Homeostasis • state of a dynamic functional balance → from individuals to the biosphere • the basic premise of the effort of all organisms → to perform life functions as long as possible • positive x negative feedback The principle of feedbacks Homeostasis • state of a dynamic functional balance → from individuals to the biosphere • the basic premise of the effort of all organisms → to perform life functions as long as possible • a prerequisite for homeostasis are sets of functional negative feedbacks that keep the system in a steady state A B Y X Y X • positive x negative feedback The principle of feedbacks Feedbacks in ecosystems or society A negative feedback • compensatory homeostatic mechanism - at all levels of the ecosystem (individuals, populations, food chains, ecosystems) E.g: Stabilization of predator and prey populations Feedbacks in ecosystems or society A negative feedback • compensatory homeostatic mechanism - at all levels of the ecosystem (individuals, populations, food chains, ecosystems) E.g: Stabilization of predator and prey populations - Maintaining a stable blood sugar level (enzyme activity, blood pressure, etc.) - In society: Economical sanctions for pollution, punishments in general Feedbacks in ecosystems https://web.microsoftstream.com/video/320fc566-e6b9-4789- 9277-51fd7849a7bf?search=river Feedbacks in ecosystems or society Positive feedback - mostly fatal in ecosystems - but! creation of a new eco-system E.g: Extinction of plant and animal species (reduction of biodiversity) - causes instability in the number of more resistant species - temperature fluctuations (extinction of plants) and environmental degradation, etc. Feedbacks in ecosystems or society Positive feedback - mostly fatal in ecosystems - but! creation of a new eco-system E.g: Extinction of plant and animal species (reduction of biodiversity) - causes instability in the number of more resistant species - temperature fluctuations (extinction of plants) and environmental degradation, etc. E.g: Rewards and compliments E.g: The relationship of the human population, food production and technologies: E.g.: Green Revolution - technol. innovation → increas in agric. production → increase in population → increase in number of potential investors → more technol. innovation → increase in agri. production → increase in population ... Feedbacks in ecosystems or society Positive feedback - mostly fatal in ecosystems - but! creation of a new eco-system E.g: Extinction of plant and animal species (reduction of biodiversity) - causes instability in the number of more resistant species - temperature fluctuations (extinction of plants) and environmental degradation, etc. E.g: Rewards and compliments E.g: The relationship of the human population, food production and technologies: E.g.: Green Revolution - technol. innovation → increas in agric. production → increase in population → increase in number of potential investors → more technol. innovation → increase in agri. production → increase in population ... Carrying capacity, growth curves of populations • CC – a property of the environment indicating how large a population can live in this environment in the long term without disturbing it Carrying capacity Carrying capacity, growth curves of populations • CC – a property of the environment indicating how large a population can live in this environment in the long term without disturbing it GC type S – logistic growth – population growth and stabilization at the CC - negative feedback between population and environment characteristics • limiting factors: eg. population density, availability of resources, predators • establishing a dynamic balance Ex. population of predators and prey, number of trees in a certain area, etc Carrying capacity Grey heron GC type J - exponential growth - CC overshoot, followed by a collapse Carrying capacity Carrying capacity, growth curves of populations GC type J - exponential growth - CC overshoot, followed by a collapse • in the case of the source of new E resources and materials, the collapse of the population may be followed by the growth again • not common in ecosystems, usually present a limmiting factor Eg: increases in cyanobacterial bloom, lemmings‘ population… • also applies to the human population, thanks to the increase in NCPs by increasingly advanced technologies dependent on the growing consumption of E, raw materials = offensive adaptation Carrying capacity Carrying capacity, growth curves of populations Food chains in ecosystems I. Grazing – prey chain • plants - 1st order consumers (herbivores) - 2nd order consumers (carnivores and omnivores). • body size increases and the number of individuals in the population decreases II. Detritic chain • dropping of dead biomass (eg leaves) - decomposition by decomposers (eg. earthworms) up to fungi and bacteria (soil, water) Food chains in ecosystems I. Grazing – prey chain • plants - 1st order consumers (herbivores) - 2nd order consumers (carnivores and omnivores). • body size increases and the number of individuals in the population decreases II. Detritic chain • dropping of dead biomass (eg leaves) - decomposition by decomposers (eg. earthworms) up to fungi and bacteria (soil, water) Food pyramide - organism at a higher level of the pyramids feed on the organisms below • is given in abundance to biomass, energy flow • upwards - large energy losses in the order of 1000: 100: 10: 1 Evolution of ecosystems succession - community development by systematic species replacement • studied eg in lava fields (primary x secondary succession) lichens, mosses → annual plants → perennials → shrubs → trees Colonization strategy • r-strategists - typical of the early stages of succession, fast life strategies - emphasis on the number and mobility of offspring; competitiveness lagged behind Evolution of ecosystems succession - community development by systematic species replacement • studied eg in lava fields (primary x secondary succession) lichens, mosses → annual plants → perennials → shrubs → trees Colonization strategy • r-strategists - typical of the early stages of succession, fast life strategies - emphasis on the number and mobility of offspring; competitiveness lagged behind • K-strategists - typical of late stages of ecosystems - emphasis on the quality and competitiveness of offspring, often long-lasting As the environment gets better, individuals start investing more in their family and romantic relationships, and become less impulsive and less aggressive. Ecosystemsandwell-being Ecosystems and well-being Ecosystems and well-being Ecosystems and well-being Ecosystems and well-being Importance of ecosystems • ecosystems → productive engines of the Earth - life