Ecosystem ecology. Food Chains and Food Webs. Domestication of plants and animals (Тексты для перевода)

 1 Вариант

1.  Read the text and translate the italised extract in written form.

ECOSYSTEM ECOLOGY

Ecosystem ecology, sometimes referred to as system ecology, is concerned with the flow of energy and circulation of matter in a whole ecosystem, that is how the whole system functions. The intimate couplings between the environment and the species: living there will influence the balance of the ecosystem and the living conditions for its members. It is only by knowing how the whole system works that we are able to understand how changes in abiotic factors that is environmental impacts, will affect a community of organisms.

Organisms can use energy in several forms. Depending on the form of "food" they use, the systems contain several categories of plants and animals.

The majority of plants obtain their energy directly from sunlight using green chlorophyll and sometimes additional pigments (like the brown and red algae). Plants are the primary producers of the ecosystem. In their photosynthesis, they convert the energy from sunlight into energy stored in carbohydrates (sugar, starch, cellulose etc.) and other organic compounds. They build biomass in the form of roots, stems and leaves. In addition to sunlight they need water, carbon dioxide from the air and nutrients such as nitrogen, potassium and phosphorus from the ground.

Animals living on plant biomass are called grazers or herbivores. They fill the role of consumers, or primary consumers, in the ecosystem.

Those animals that live by catching other living animals are predators, or carnivores, also called secondary consumers.

Finally, bacteria, and other organisms living on dead organic matter, detritus, are called decomposers. Soil  animals, such as earthworms make up the first stage in the  ecomposition  of detritus, while fungi and bacteria take care of the final decomposition. By decomposing the organic matter they return the nutrients to mineral form and the organically bound  carbon to carbon dioxide. The roots of plants can then again capture the mineral nutrients, and the circulation of chemical matters is closed. The decomposers are in many ways the most important  organisms in the ecosystem. Plant growth in most terrestrial ecosystems is limited by the lack of nitrogen and in  aquatic ecosystem often by lack of phosphorus. If the decomposers did not effectively re-circulate these nutrients, primary production would soon cease. Re-circulation of nutrients and other substances is   thus essential to all ecosystems.

TASK1. GRAMMAR

A. TURN THE FOLLOWING VERBS INTO NOUNS AND TRANSLATE THEM INTO RUSSIAN:

1. to affect;

2. to describe;

3. to protect;

4. to observe;

5. to violate;

B. TURN THE FOLLOWING NOUNS INTO VERBS AND TRANSLATE THEM INTO RUSSIAN:

6. population;

7. eutrophication;

8. addition;

9. gradation;

10. exploitation.

TASK2.

REFER THE MODAL VERBS TO THE PAST AND FUTURE WHERE POSSIBLE:

1. Organisms can use energy in several forms.

2. Animals are able to receive their nitrogen through the food.

3. We may also discuss the whole system involved in material flows.

4. The plants may be unable to take up all nutrients.

5. It should be possible to improve control.

6. A first step must follow and “harvest” the wild herd.

7. The use of natural resources must be balanced.

8. We have to make both continental and global comparisons whenever