Define ecology, biogeography, ecosystem, and the community. Explain photosynthesis and respiration, and derive net photosynthesis and the world pattern of net primary productivity. Relate abiotic ecosystem components to ecosystem operations, and explain trophic relationships. Solution Ecology :-The prefix \'eco\' has become synonymous with environmentally-friendly living. This green fad, however, has more to do with conservation biology than with ecology, where the prefix is borrowed from.All organisms, no matter their size, their species, or where they live, need to interact with other organisms in their \'neighborhood\' and with their environment in order to survive.Ecologyis the scientific study of the interactions between organisms and their environment. The term comes from the Greek \'study of house\', or the study of the place we live in.The scope of ecology is huge, and it encompasses all organisms living on Earth andtheir physical and chemical surroundings. For this reason, the field is usually divided into different levels of study including: organismal ecology, population ecology, community ecology and ecosystem ecology. Biogeography:-Biogeography is broken into two subcategories:*.Phytogeography, the study of how plants are distributed on the earth*. Zoogeography, the study of how animals are distributed on the earth (including bacteria)Biogeography is very important in understanding how animals and plants have changed the landscape over time. This field utilizes knowledge from the study of rocks or geology, the study of ecosystems or ecology, and the study of the physical planet or physical geography to answer questions about how organisms react to changes in their environment. Ecosystem:-An ecosystem includes all of the living things(plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere). Photosynthesis:-Photosynthesis is the process used by plants, algae and certain bacteria to harness energy from sunlight into chemical energy.There are two types of photosynthetic processes: oxygenic photosynthesis and anoxygenic photosynthesis. Oxygenic photosynthesis is the most common and is seenin plants, algae and cyanobacteria.undefined During oxygenic photosynthesis, light energy transfers electrons from water (H2O) to carbon dioxide (CO2), which produces carbohydrates. In this transfer, the CO2 is \"reduced,\" or receives electrons, and the water becomes \"oxidized,\" or loses electrons. Ultimately, oxygen is produced along with carbohydrates. Respiration:-It may be associated with:*.breathing, which is the process of inhaling and exhaling gases from and into theexternal environment– a function of the lungs and other structures with similar function (e.g.gills)*.cellular respiration, which is the process utilized by cells to obtain energy from theoxidationoforganic compoundsaccompanied by the consumption ofoxygen(when availa.

1. Define ecology, biogeography, ecosystem, and the community. Explain photosynthesis and
respiration, and derive net photosynthesis and the world pattern of net primary productivity.
Relate abiotic ecosystem components to ecosystem operations, and explain trophic relationships.
Solution
Ecology :-The prefix 'eco' has become synonymous with environmentally-friendly living. This
green fad, however, has more to do with conservation biology than with ecology, where the
prefix is borrowed from.All organisms, no matter their size, their species, or where they live,
need to interact with other organisms in their 'neighborhood' and with their environment in
order to survive.Ecologyis the scientific study of the interactions between organisms and their
environment. The term comes from the Greek 'study of house', or the study of the place we live
in.The scope of ecology is huge, and it encompasses all organisms living on Earth andtheir
physical and chemical surroundings. For this reason, the field is usually divided into different
levels of study including: organismal ecology, population ecology, community ecology and
ecosystem ecology.
Biogeography:-Biogeography is broken into two subcategories:*.Phytogeography, the study of
how plants are distributed on the earth*.
Zoogeography, the study of how animals are distributed on the earth (including
bacteria)Biogeography is very important in understanding how animals and plants have changed
the landscape over time. This field utilizes knowledge from the study of rocks or geology, the
study of ecosystems or ecology, and the study of the physical planet or physical geography to
answer questions about how organisms react to changes in their environment.
Ecosystem:-An ecosystem includes all of the living things(plants, animals and organisms) in a
given area, interacting with each other, and also with their non-living environments (weather,
earth, sun, soil, climate, atmosphere).
Photosynthesis:-Photosynthesis is the process used by plants, algae and certain bacteria to
harness energy from sunlight into chemical energy.There are two types of photosynthetic
processes: oxygenic photosynthesis and anoxygenic photosynthesis. Oxygenic photosynthesis is
the most common and is seenin plants, algae and cyanobacteria.undefined During oxygenic
photosynthesis, light energy transfers electrons from water (H2O) to carbon dioxide (CO2),
which produces carbohydrates. In this transfer, the CO2 is "reduced," or receives electrons, and
the water becomes "oxidized," or loses electrons. Ultimately, oxygen is produced along with
carbohydrates.
Respiration:-It may be associated with:*.breathing, which is the process of inhaling and exhaling
gases from and into theexternal environment– a function of the lungs and other structures with

2. similar function (e.g.gills)*.cellular respiration, which is the process utilized by cells to obtain
energy from theoxidationoforganic compoundsaccompanied by the consumption ofoxygen(when
available) and the release ofcarbon dioxide*.anaerobic respiration, a process in whichcellular
respirationoccurs not involving the use of molecularoxygen*.plantrespiration, the
enzymaticoxidationofsubstratesinplants, leading to the release ofcarbon
dioxide*.carbonrespiration – a phrase used in combination withcarbonstorage to calculatethe
amount of carbon (as CO2)fluxoccurringin theatmospherethrough the various processes that add
and subtractatmosphericcarbon
Net photosynthesis:-The difference between the total amount ofphotosynthesisand the sum of the
rates ofrespiration(i.e.photorespiration and dark respiration).
Net primary productivity:-The rate at which an ecosystem accumulates energy or biomass,
excluding the energy it usesfor the process of respiration. This typically corresponds to the rate
of photosynthesis,minus respirationby the photosynthesizers.
Relating abiotic ecosystem components to ecosystem operations:- Anecosystemis defined as any
community of living and non-living things that work together. Ecosystems do not have clear
boundaries, and it may be difficult to see where one ecosystem ends and another begins. In order
to understand what makes each ecosystem unique, we need to look at the biotic and abiotic
factors within them.Biotic factorsare all ofthe living organisms within an ecosystem. These may
be plants, animals, fungi, and any other living things.Abiotic factorsare all of the non-living
things in an ecosystem.Both biotic and abiotic factors are related to each other in an ecosystem,
and if one factor is changed or removed, it can affect the entire ecosystem. Abiotic factors are
especially important because they directly affect how organisms survive.Examples of Abiotic
FactorsAbiotic factors come in all types and can vary among different ecosystems. For example,
abiotic factors found in aquatic systems may be things like water depth, pH, sunlight, turbidity
(amount of water cloudiness), salinity (salt concentration), available nutrients (nitrogen,
phosphorous, etc.), and dissolved oxygen (amount of oxygen dissolved in the water). Abiotic
variables found in terrestrial ecosystems can include things like rain, wind, temperature, altitude,
soil, pollution, nutrients, pH, types of soil, and sunlight.The boundaries of an individual abiotic
factor can be just as unclear as the boundaries of an ecosystem. Climate is an abiotic factor -
think about how many individual abiotic factors make up something as large as a climate.
Natural disasters, such as earthquakes, volcanoes, and forest fires, are also abiotic factors. These
types of abiotic factors certainly have drastic effects on the ecosystems they encounter.
Trophic relationships:-The trophic dynamics of a newly-impounded south east Asian reservoir,
Pasak Jolasid, Thailand, monitored from its creation, were constructed usingecopath, a mass-
balanced model. The trophic levels (TLs) of 36 ecological groups varied between 1.0 and3.2.
The majority of fish biomass was at the second TL, where the fishery is concentrated. Some food

3. resources (benthic organisms and zooplankton) were not fully used, whereas phytoplankton and
benthic algae were important components of the food web, which is based on phytoplankton and
detritus. The implications of these findings are discussed interms of ecological maturity of the
ecosystem and possible fishery management of this multi-purpose reservoir.