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of food, which is necessary for a population to demonstrate high growth and repro-
duction. The animal also must find favourable temperatures and oxygen conditions,
while avoiding predators, diseases and parasites.
As we examine environments from small ponds through rivers, lakes and
oceans, understanding the factors controlling fish production become progressively
more difficult. In small ponds, food availability often controls fish production, but the
factors that control the survival of young oceanic fishes and their ultimate productivi-
ty is one of the greatest challenges to the fisheries scientist. Only certain fishes, shell-
fishes and algae have the characteristics necessary for harvesting by humans. They
must be abundant and, at some time during their adult life, should be concentrated in
a predicable area so they are accessible to fishing gear. A species value as human
food depends on its acceptability in our diet, nutritional quality and accessibility. Or-
ganisms that are highly valued by one society may be ignored or considered repug-
nant by another. Many species having no value as human food are fished for reduc-
tion to fish meal used in livestock and aquaculture feeds. These species constitute
some of our largest fisheries in terms of catch weight. Ecology is best studied within
the context of ecosystems, rather than considering only the species of interest. An
ecosystem includes includes all of the interacting organisms and physical-chemical
components. Within an ecosystem, the flow of chemical elements, such as carbon,
oxygen, nitrogen and phosphorus, and the flow of energy from sunlight through pho-
tosynthesis into organic material and its utilization by respiration are linked.
Write a summary of the text in Russian
TEXT 8
CONSERVING BIODIVERSITY IN THE BERING SEA
Several years ago World Wildlife Fund (WWF) worked with scientists around the
world to identify the most critical areas for preserving biological diversity. As a result
of this work these experts identified over 200 areas which we call ecoregions. In
theory, if we, the international conservation community, could preserve the biodiver-
sity in these ecoregions, we would be protecting most of the diversity of life on the
planet.
Of these Global 200 ecoregions, 61 were marine. And one of these marine eco-
regions was the Bering Sea. Why did the international group of experts consider the
Bering Sea to be such a globally important area? Primarily because the Bering Sea is
one of the most productive northern marine ecosystems in the world. As many of you
know, the sea is home to …. More than 450 species of fish, mollusks and crusta-
ceans;
…. Some 50 species seabirds, and million of birds which migrate annually from all
over the world to nest in various coastal and marine habitats.
…. Some 25 marine mammals, many of which occur in high concentrations through-
24
of food, which is necessary for a population to demonstrate high growth and repro-
duction. The animal also must find favourable temperatures and oxygen conditions,
while avoiding predators, diseases and parasites.
As we examine environments from small ponds through rivers, lakes and
oceans, understanding the factors controlling fish production become progressively
more difficult. In small ponds, food availability often controls fish production, but the
factors that control the survival of young oceanic fishes and their ultimate productivi-
ty is one of the greatest challenges to the fisheries scientist. Only certain fishes, shell-
fishes and algae have the characteristics necessary for harvesting by humans. They
must be abundant and, at some time during their adult life, should be concentrated in
a predicable area so they are accessible to fishing gear. A species value as human
food depends on its acceptability in our diet, nutritional quality and accessibility. Or-
ganisms that are highly valued by one society may be ignored or considered repug-
nant by another. Many species having no value as human food are fished for reduc-
tion to fish meal used in livestock and aquaculture feeds. These species constitute
some of our largest fisheries in terms of catch weight. Ecology is best studied within
the context of ecosystems, rather than considering only the species of interest. An
ecosystem includes includes all of the interacting organisms and physical-chemical
components. Within an ecosystem, the flow of chemical elements, such as carbon,
oxygen, nitrogen and phosphorus, and the flow of energy from sunlight through pho-
tosynthesis into organic material and its utilization by respiration are linked.
Write a summary of the text in Russian
TEXT 8
CONSERVING BIODIVERSITY IN THE BERING SEA
Several years ago World Wildlife Fund (WWF) worked with scientists around the
world to identify the most critical areas for preserving biological diversity. As a result
of this work these experts identified over 200 areas which we call ecoregions. In
theory, if we, the international conservation community, could preserve the biodiver-
sity in these ecoregions, we would be protecting most of the diversity of life on the
planet.
Of these Global 200 ecoregions, 61 were marine. And one of these marine eco-
regions was the Bering Sea. Why did the international group of experts consider the
Bering Sea to be such a globally important area? Primarily because the Bering Sea is
one of the most productive northern marine ecosystems in the world. As many of you
know, the sea is home to …. More than 450 species of fish, mollusks and crusta-
ceans;
…. Some 50 species seabirds, and million of birds which migrate annually from all
over the world to nest in various coastal and marine habitats.
…. Some 25 marine mammals, many of which occur in high concentrations through-
24
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