Net Primary Productivity (NPP) Rate in which energy for use by consumers is stored in new biomass of plants – Measured in kilocalories per square meter per year or grams in biomass – NPP is the limit determining the planet’s carrying capacity for all species. – 59% of NPP occurs in land / 41% occurs in ocean

Food Chain Food Chain-Series of organisms in which each eats or decomposes the preceding one – Decomposers complete the cycle of matter by breaking down organic waste, dead animal. Plant litter and garbage. – Whether dead or alive organisms are potential (standard) sources of food for other organisms.

Food Web Complex network of interconnected food chains Food web and chains – One-way flow of energy – Cycling of nutrients through ecosystem

Food Webs Grazing Food Webs – Energy and nutrients move from plants to herbivores – Then through an array of carnivores – Eventually to decomposers (100,000 Units of Energy)

Food Webs Grazing Food Webs – Energy and nutrients move from plants to herbivores – Then through an array of carnivores – Eventually to decomposers (1,000 Units of Energy)

Second Law of Energy Organisms need high quality chemical energy to move, grow and reproduce, and this energy is converted into low-quality heat that flows into environment – Trophic levels or feeding levels- Producer is a first trophic level, primary consumer is second trophic level, secondary consumer is third. – Decomposers process detritus from all trophic levels.

Food Webs Grazing Food Webs – Energy and nutrients move from plants to herbivores – Then through an array of carnivores – Eventually to decomposers (100 Units of Energy)

Food Webs Grazing Food Webs – Energy and nutrients move from plants to herbivores – Then through an array of carnivores – Eventually to decomposers (1 Units of Energy)

Food Webs Grazing Food Webs – Energy and nutrients move from plants to herbivores – Then through an array of carnivores – Eventually to decomposers (10 Units of Energy)

Food Webs Detrital Food Webs – Organic waste material or detritus is the major food source – Energy flows mainly from producers (plants) to decomposers and detritivores.

Pyramid of Energy Flow More steps or trophic levels in food chain or web, greater loss of usable energy as energy flows through trophic levels More trophic levels the Chains or Webs have more energy is consumed after each one. That’s why food chains and webs rarely have more than 4 steps

Distinction between Species Wild species- one that exists as a population of individuals in a natural habitat, ideally similar to the one in which its ancestors evolved Domesticated species- animals such as cows, sheep, food crops, animals in zoos

Living Organisms – Capture and transform matter and energy from their environment to supply their needs for survival, growth, and reproduction – Maintain favorable internal conditions, despite changes in their external environment through homeostasis, if not overstressed

Biomass Dry weight of all organic matter contained in organisms. – Biomass is measured in dry weight Water is not source of energy or nutrient – Biomass of first trophic levels is dry mass of all producers – Useable energy transferred as biomass varies from 5%-20% (10% standard)

Pyramid of Biomass Storage of biomass at various trophic levels of ecosystem

Pyramid of Energy Flow Loss of usable energy as energy flows through trophic levels of food chains and webs Rarely have more than 4 steps

Pyramid of Numbers Number of organisms at each trophic level

Gross Primary Productivity (GPP) Rate in which producers convert solar energy into chemical energy (biomass) in a given amount of time