Man not only destroys the habitat, but by changing the landscape, he creates a new one. For some species this becomes a blessing
Not all animals are as unlucky as beavers. Once inhabiting vast territories, at the beginning of this millennium they are practically not found in Germany. Not only did the person change the world around us and thereby deprived the beavers of their habitat - 80% of the floodplains have disappeared, the rivers are becoming increasingly polluted - people are also driving out what they consider to be annoying rodents. For some time they practically disappeared from view altogether. But other species would have no chance of surviving without humans.
Biologists from the University of Frankfurt have been conducting research on species diversity in the Rhine-Main region for many years. “Many species exist precisely because humans interfere with nature,” explains Rüdger Wittig, professor of ecology and geobotany at the University of Frankfurt. “Without humans, Europe would be almost entirely covered in forests. Thanks to our intervention, clearings, pastures, fields and arable lands appeared - new habitats, thanks to which the diversity of species has increased significantly.
Two destructive mechanisms
Agriculture has led to an increase in species diversity. "At the border areas there is just the most large number species,” explains the ecologist. – In a clearing, for example, you can find both those species that need a forest to live, and those that live in clearings. This also includes some animals and plants that have adapted to living in these border areas."
Many such border areas have been eliminated because agriculture covers more and more territories. As a result, the number of species in turn decreases. Some species are also affected by the use of fertilizers and weed killers. “The use of fertilizers increases the yield,” explains Wittig. “But species that previously grew in border areas, such as cornflower, poppy and chamomile, disappear. A decrease in plant diversity also leads to a decrease in animal diversity.”
Station Paradise
The number of species and habitats are constantly changing, especially in cities. This is evidenced by the observations of scientists from the University of Frankfurt. "At train stations and in areas of old industrial enterprises you can find many species," notes Wittig. A shrub called David's buddleia, introduced from East Asia (another name is "autumn lilac." - Editor's note), has spread throughout the Rhine-Main region. "This shrub has benefited from human activity , explains the ecologist. “It grows where people have settled before - it needs a lot of light.” In abandoned areas railway biologists also discover wall lizards, the number of which is growing over time. But if these territories remain abandoned for many decades, then white acacias and birches displace the original vegetation along with lizards.
Plants (Latin Plantae or Vegetabilia) are studied by the science of botany; in the 21st century, scientists count more than 320 thousand species of plants, most of which are flowering plants (about 280 thousand species), the number of plants increases every year, new species are constantly being discovered.
What would our planet be like without plants?
The role of plants both in nature and in life and economic activity it is difficult to overestimate a person. Thanks to the process of photosynthesis occurring in the green leaves of plants with the participation sunlight Oxygen is formed, which is vital for all inhabitants of the earth's surface. Plants are the richest source of vitamins and minerals, an indispensable element of trophic food chains, and a producer of various organic substances in nature from inorganic raw materials. If there were no plants in nature, then there would be no animals, no man himself, and the planet itself would look like a lifeless desert, there would not even be soil on it and no landscape diversity created precisely by plant groups. A person must appreciate and understand the role of plants in his life, because without them he simply would not exist; by planting and caring for the small sprouts of green life, we become cleaner and kinder, we become familiar with the mysteries of nature and the universe.
Photosynthesis as a great cosmic process that makes our planet habitable
One of the most important functions of green plants is the production of oxygen through the process of photosynthesis. The leaves of green plants contain the pigment chlorophyll, which, under the influence of sunlight, divides the water drawn from the soil by the roots into hydrogen and oxygen (the process of photolysis). Also, carbon dioxide absorbed by plants in the presence of chlorophyll and without the necessary participation of sunlight reacts with water, forming glucose and oxygen (the process of carbon dioxide reduction). By combining the resulting glucose with sulfur, nitrogen and phosphorus compounds obtained from the soil, plants generate proteins, fats, starch, various vitamins and other complex compounds necessary for their further life.
What other benefits do plants provide to nature?
The rate of photosynthesis depends on the intensity of light, the concentration of oxygen and carbon dioxide, temperature environment. The resulting O2 is partially released into the atmosphere, and partially goes into the respiration of the plants themselves. Every year, plants release up to 510 tons of oxygen into the atmosphere; they maintain its constant gas balance to a state suitable for breathing. Rising to the upper layers of the atmosphere, oxygen turns into ozone and becomes part of the ozone layer, which protects our planet from the harmful UV radiation of the Sun.
Every year, plants produce up to 170 billion tons of organic matter, most of which is produced by terrestrial plants. With the help of plants, the upper fertile layer of the Earth, called soil, is formed; they provide it with a constant circulation of minerals, which is so necessary for its fertility.
Plants, due to the fact that they return 90% of the moisture that land evaporates into the atmosphere, significantly soften the Earth’s climate and form temperature regime planets. By absorbing carbon dioxide they reduce the so-called greenhouse effect, although man, as a result of his economic activities (burning fuel and cutting down large areas of humid equatorial forests), is trying to reduce all the efforts of the “lungs of the planet” to zero.
Vegetation, covering the ground with a dense carpet, protects it from drying out, creates a milder, humid climate, roots keep the soil from weathering and erosion, and prevent the appearance of ravines and landslides. Plants release specific substances, phytoncides, into the air, which are destructive to pathogenic bacteria and are the first important step in the trophic food chain.
Man and plants
Plants play a huge role in human life, because in addition to the fact that they are sources of oxygen necessary for breathing, they are used by humans as food (cereals, vegetables, grains and legumes, tree fruits, essential oil crops, sugar plants), and medicines are made from them , clothes, houses, they serve as raw materials for industrial production paper, paint, rubber and other various useful substances.
Plants are an irreplaceable source of vitamins and minerals, the deficiency of which can lead to the development of serious diseases in humans. In livestock farming, feed crops are used as food for animals; in large cities they absorb excess carbon dioxide, serve for sanitary and hygienic purposes, absorbing harmful substances from the air, ionizing it and moisturizing it.
The lesson summary is compiled in accordance with the requirements of the Federal State Educational Standard. In this lesson, students are expected to use computer equipment and electronic folders with materials on the subject. Students independently gain knowledge on the topic using a variety of information both electronically and in paper form, draw conclusions, and use the acquired knowledge to solve lesson problems and environmental problems.
Download:
Preview:
Polyakova Marina Nikolaevna,
teacher of biology and chemistry MBOU Secondary School No. 130, Ussuriysk, Primorsky Territory
Topic: “Current state and protection of vegetation”
Form of organization of educational activities:
- Frontal;
- Individual.
Teaching methods:visual and illustrative, partially search, group, discussion
Objective of the lesson: promote environmental education of students when studying biological resources and the need for their rational use.
Tasks:
- Deepen your understanding of the role of plants in nature and human life;
- Form the concepts of “biological resources”, “reserve”;
- Show examples negative impact people on living nature, examples of rational use of biological resources;
- To develop the ability to predict the use of vegetation as a result of human economic activity;
- Promote student involvement in research activities on a practical subject.
Equipment: atlases Primorsky Krai, Red Book of the Russian Federation, Red BookPrimorsky Krai and Ussuriysk region, booklets about rare and endangered plant species of the Primorsky Territory,DVD player, multimedia projector, student presentations, information sheets, task cards, electronic folders with lesson material, teacher presentation.
I. Preparatory stage:
- Two students are cookingpresentations on the topics "on the topics “Human influence on wildlife”, “Plant protection in Russia”;
- One student carries out project work on the topic “Rare and endangered plant species of the Primorsky Territory” using the example of the Far Eastern Lily; the results are presented in the form of a presentation, an XL test, or a booklet.
- Students in the class are invited to supplement the electronic folder of materials with articles on this topic.
II. Lesson progress (synopsis - diagram).
No. | Seminar questions | Time | Teacher activities | Student activities | Slide no. |
Organizational moment. | Lesson topic message, general education, lesson outline | Write down the topic of the lesson in a notebook and get acquainted with the seminar program. | №1 |
||
Updating knowledge. Epigraph of the lesson. | The teacher tells the students the epigraph of the lesson: “Of all the “machines” that work for us, the forest is one of the most durable, but also the most difficult to repair.” L. Leonov | Students listen to the epigraph and discuss it. | №2 |
||
Statement of the lesson problem | The teacher poses a problem to the students that needs to be solved in class.: There was an alley of linden trees on the street. One day a bulldozer appeared and moved towards the trees. The first to see him were old women sitting on a bench and asked the bulldozer driver what he was going to do. He replied that pipes would be laid here and therefore the trees needed to be uprooted. And he got behind the wheel again. Then the women positioned themselves right on the ground in front of the trees. The guy was confused... and turned back. An engineer from the construction trust arrived. And it turned out that it was quite possible to lay a trench several meters to the side without touching the trees. Could there not have been a conflict? How might events develop? What decision did the construction trust workers need to make in order to solve their problem and not cause damage? green spaces cities? | Students listen to a problem and make preliminary, written sketches of its solution. | №3 |
||
Lesson Plan | The teacher introduces students to a lesson plan that will help solve the lesson problem. Plan: 1 The role of plant resources in the life of the biosphere and in human life. 2 Causes and consequences of forest loss. Fighting forest fires. 3 Protection and restoration of forests. Rational forest management 4 Reasons for disappearance rare species plants. Protected plants of the native land. | Students listen to the lesson plan | №4 |
||
The stage of learning new knowledge and ways of doing things Work in small groups. | The teacher gives tasks to students in groups to work with electronic folders and student presentations. 1st group: Group 2: Group 3: Group 4: Group 5: | Students work with electronic folders and presentations, complete tasks given to groups, and prepare information sheets (Appendix No. 1) Sample answers: 1st group: Creation of biological products, due to which all other organisms exist; Constantly replenishing oxygen reserves and maintaining carbon dioxide levels; Maintaining the water cycle in nature; Soil protection from erosion; Maintaining a certain microclimate. Group 2: Providing food; Security various industries economic activities (wood, raw materials for the textile industry, medicinal plants); Sanitary value (dust retention); Recreational value (rest, treatment, satisfaction of cognitive interests, sports activities, tourism). Group 3: Forests are cut down in order to expand cultivated areas for the construction of industrial facilities, cities, and transport communications; The wood is high quality building material; Furniture, paper, pencils, matches, etc. are made from various types of trees; Wood is used as fuel; Forests are shrinking and degrading due to air pollution; Forest fires. Group 4: Water is not retained by the litter, roots and flows down the slopes; The top layer of soil is washed away; Gullies are formed; River mouths are flooded and shallow, fresh water supplies are decreasing; Yields in adjacent fields are decreasing, etc. Group 5: The practice of cutting down certain tree species and plant collections for pharmaceutical production and collections; Chemical pollution; Conversion of land for agricultural needs and many other methods leading to a decrease in the populations of certain plants, etc. | |||
The stage of consolidation and application of what has been learned Summing up the results of group work. | The teacher organizes a summary of the work in groups and participates in the discussion of issues. | Individual presentations by students with answers to group assignments. Participants in other groups fill out their information sheets. | |||
Defense of the project “Protected Plants of the Native Land” | The teacher invites the students to listen to a story about project work schoolgirls on the topic “Protected plants of their native land” | Speeches by the student with a message about her project work and its product. Demonstration of project products (booklet, presentation, test) (Appendix No. 2) | №5 |
||
VIII | Solving a lesson problem. | Introductory speech by the teacher, participation in the discussion. | Students speak, participate in discussions, record their conclusions. | №6 |
|
Stage summing up results and reflection Summary of the seminar. | The teacher, together with the students, draws a conclusion about the wealth of biological resources in Russia, their vulnerability and protection, about the students’ capabilities in organizing and carrying out environmental protection measures; Grading for the lesson. The teacher assigns homework: Creative (booklet, rules of behavior in the forest, prevention of forest fires, protection of rare plant species of the native land) Solving individual environmental problems (Appendix No. 4) Creation of an electronic folder on the topic “Rational use and protection of animals” | Or students draw their own conclusions. (Appendix No. 3) | № 7-8 |
||
Reflection. | Let's remember what new concepts we met today. Which concept is the easiest? What question stood out to you the most? What new did you learn today? What question might be difficult for you? |
Conclusion: They are different:
Useful, dangerous,
Beautiful, fragrant,
With leaves, prickly.
The medicine is replaced
And they are a delicacy
And they will give us tea,
And they will even build a house,
They are creatures of the earth,
We call them PLANTS.
Appendix No. 1
“Current state and protection of vegetation”
Information sheet
Quests | Answer |
1st group: Describe the role of vegetation in the life of the biosphere | |
Group 2: Describe the role of plant resources in human life. | |
Group 3: Indicate the main reasons for the decline in the world's forest resources. Fighting forest fires. | |
Group 4: Indicate the consequences of deforestation along river banks, in adjacent areas and within the city. Forest protection and restoration. | |
Group 5: Indicate the reasons for the disappearance of rare plant species. The role of nature reserves and national parks in the protection of rare and endangered plant species. The role of schoolchildren in protecting the forest. |
Appendix No. 3 Solving the problem
This story presents typical positions in the relationship between man and nature. One of the parties is the construction trust represented by an engineer and a bulldozer operator. The other is grandmothers, residents of this area. For an engineer, a street is just another object, a place of work, and most importantly, not a street, but a pipeline. For a bulldozer driver it’s even simpler: “They told me to do it, but what do I have to do, my job is to do it.” For both, the street is alien, both are indifferent to how their actions will respond. And for women, the street is “ours”; we lived on it, and we will continue to live on it. What about its decoration, its freshness - but under the knife of a bulldozer?
The difference in positions comes from the rootedness of some in this world and the indifference of others to it. It’s good that the conflict stopped one, made the other think, and led to a change in the decision made from a narrowly professional point of view. Could there not have been a conflict? Certainly! For example, women, sitting on a bench, would look at the uprooting of trees and condemn the bulldozer driver, but would not take any action: “Our business is our side, we are small people, the authorities know better.” And the alley would disappear, just as entire green areas, gardens and parks disappear in our cities as a result of the same “strong-willed” decisions. They are based on the narrow-mindedness of irresponsible leaders of various ranks and levels and equally irresponsible day laborers.
But there might not have been a conflict at all if the bulldozer driver, having arrived at the scene, wondered whether it was necessary to destroy the alley! Maybe they didn’t think about it when signing his outfit and we need to look for another solution. Or if an engineer who was drawing up a detailed design for laying a pipeline route (water supply, telephone or electric cable) walked along the future route, looked for himself, thought about it and found an economic direction for work without damaging the alley.
What was missing was just a little: human interest and professional responsibility. There was not enough sense of ownership or a sense of patriotism - love for one’s city, care for it...
(V. Ivanov “Conflict of values and solving environmental problems”, - M.: Znanie. 1991. No. 8.)
Appendix No. 4 Environmental challenges
Problem No. 489 Mudflow - a dangerous natural phenomenon, which is a rapid mud flow in the mountains caused by snowmelt or heavy rains. These flows can cause enormous destruction and loss of life. Explain why mudflows are practically absent in places where the population in the mountains is low. Why is the probability of mudflows very high in places where forests are cut down in the mountains and (or) domestic animals are grazed?
Problem No. 491 Explain why in national parks and in protected areas, visitors are only allowed to walk along paths and paths. Why is this requirement especially strict in hilly and mountainous areas?
Problem No. 494 Explain why spruce is very sensitive even to runaway ground fires when moss, pine needles and grass burn on the ground?
Problem No. 495 Small-leaved linden lives in the forest for up to 300 - 400 years, in urban conditions - up to 150 years. The branches of pines growing in the city die off at the tops. Answer what is the reason for the poor development of trees in the city.
Problem No. 500* Thanks to humans, many plant species moved from one continent to another and successfully reproduced there. What properties are usually characteristic of such migrants? Which communities are easier to move into, and which are more difficult, and why? What consequences might such an introduction have for native species?
Problem No. 502* Describe how plant populations have changed since beautiful flowers may arise as a result of intensive collection of flowering specimens for bouquets.
Problem No. 503** The famous French researcher of the African Sahara, Henri Lot, describes the transformation of the flourishing region of Nigeria Air into a lifeless desert in just a few months: “In 1973, a tragedy broke out. The rainy season started too early and ended suddenly. Since February, the pastures of the northern zones of Air were completely devastated (until this year a lot of people and domestic animals lived here), and the herds had to be driven south, to more favorable places that could not withstand such an influx of livestock. The nomads found themselves in complete hopeless situation, nothing could save them from the impending disaster. As a last source of food for goats, the top branches of acacia trees were cut down, devastating entire valleys, inexorably accelerating the death of trees and thereby contributing to the onset of the desert... hence the conclusion: it is not the desert that is advancing, but the nomads, by destroying vegetation, contribute to its onset.”
What measures do you think need to be taken in drylands to avoid increasing desertification? For example, the Sahara is advancing to the south of the continent along its entire front at an average speed of 48 km per year.
Competition between different plant species affects the characteristics of the existence of multispecies crops, for example, between weeds and cultivated flora
These competitive relationships are much more complex than those that arise within a species. This is due to the fact that species differ from each other not only in morpho-physiological characteristics, but also in competitive, as well as environmental requirements for various environmental factors, resistance to pathogens and agricultural pests, and so on. By changing the habitat, it is possible to achieve a change in the nature of relationships between species. Experiments conducted in the southern regions of Tajikistan on blue millet and alfalfa crops made it possible to calculate that without applying fertilizers, millet is capable of increasing only 20 g of dry mass at a time when alfalfa had an indicator 7 times higher. Under conditions of nitrogen mineral nutrition for millet, its accumulation of biomass increased to 160 g. At the same hour, the intensity of the increase in dry mass of alfalfa dropped to 100 g.
Plants and their competitive ability - what else you need to remember
In phytoassociations where dominance is clearly expressed in more than one species, the ability to maintain competitive positions is very low in both old and young individuals. This can be justified by the high mortality of plant organisms in senile or senile groups and among growing specimens (in the juvenile group). Through experiments, again on Tajik lands with blue millet, it was possible to establish that after sowing it in a mixture of various cereal and legumes By the end of 3-4 years it is completely knocked out of the sowing. In the grass cover, even without the addition of mineral nutrition, it can persist for up to 8 years.
Multiple cuts of vegetative areas of plants, their frequency and periodicity, also have an effect on the resistance of plants. As a rule, the more often this happens, especially for those whose reproduction occurs primarily by seeds, the less ability it has to compete. this plant. After all, as the people say, “A holy place is never empty!” The same principle applies in this situation. Plants that reproduce by vegetative parts of the body do not fall under it.
Weeds entering cultivated crops demonstrate fairly good inclinations to compete, due to their higher ecological valence to environmental conditions. Therefore, exceptionally competent agricultural techniques can effectively overcome this problem. And they must be built taking into account the characteristics of the biology of certain species against which these measures are being undertaken.
It is believed that the best time to start them is the harvesting period, i.e. with summer-autumn soil cultivation for future crops. Then it will be effective to introduce herbicides into the soil to help fight weeds. It is advisable to implement these procedures annually until the weeds are completely eradicated from your land.
To date, created modern methods to eradicate pests and weeds, the systematicity and appropriateness of which affects the quality result of their implementation. They are usually grouped into three groups:
- agrotechnical;
- chemical;
- biological.
It must be said that only comprehensive and systematic approach to this problem can provide a positive outcome. Just as it is not guaranteed to use the same approaches over a long period of time. In the latter case, it can lead to even more undesirable consequences than before.
Allelopathy or chemical control between plants
In multispecies, complex crops, chemical interactions occur between plant individuals. They manifest themselves through the influence of substances released by plants into the soil, which concentrate in it and lead to soil fatigue. In addition, it is possible that these secretory products act directly, aimed at suppressing nearby flora. Due to the high chemical activity of plant communities, a new term even appeared - allelopathic soil fatigue, which means the process of accumulation chemical compounds biological origin to highly toxic concentrations that can cause negative impact on the vital activity of neighboring individuals, as well as cause unidirectional growth of phytopathogenic microflora.
Such a chemical effect can be produced by substances that are quite mobile in the soil solution, for example, phenolic compounds. But besides the harm they can cause, it acts as a kind of chemical weapon for nearby vegetative weeds. It has been established that barley crops are less susceptible to attacks individual species weeds thanks to the secretions of the alkaloid gromina, to which the latter turn out to be very sensitive.
But not all agricultural plants are so chemically active. Other representatives that are distinguished by this property include buckwheat, hemp, and rye. Back in the middle of the last century, it was proven that growing alfalfa in the same field for several years leads to the accumulation of saponins in the soil - complex nitrogen-free substances with good surface-active properties. They, in turn, have an inhibitory effect on the germination of, for example, cotton seeds.
But we also cannot overdo this property of our cultivated varieties. It is recommended to alternate crops from year to year to avoid severe soil fatigue. Lupine can often cause it.
Growing wheat in monoculture entails saturation of the soil with phenols. Crops such as grapes, potatoes, corn, rice, tobacco do not have the ability to greatly tire the soil, so cultivating them as a monoculture is allowed.
However, it is not only the cultivated flora that is chemically active against its biological rivals. The opposite option is also possible, when wild species use the same remedy to combat them. A striking example of such an effect is the allelopathic activity of wheatgrass, white goosefoot or quinoa and crabgrass on corn.
Horse sorrel has a negative effect on many agricultural plants, the phenols of which can inhibit the growth of sorghum and corn. It is noteworthy that in this way it also eliminates its competitors for habitat. The same fire or shepherd's purse cannot withstand this pressure and usually gives up its place to it.
Salad mustard is not inferior to it in its activity. And it was noticed a long time ago useful property onions growing between rows of potatoes or tomatoes, protect them from late blight attacks. Cabbage planted between the rows of grapes can significantly suppress them.
It is interesting how India is fighting the problem of cotton root rot. This is facilitated by planting beans in row spacing, which significantly reduces the percentage of affected individuals among this crop.
Nowadays, many years of testing have accumulated a lot of data on how plants, by concentrating certain compounds in themselves, are able to influence their own kind and other weed species, influence their growth, the absorption of nitrogen by bacteria, and the germination of seeds. Few people have heard and tested from their own experience the old-fashioned way of dealing with attacks Colorado potato beetles for potatoes. To do this, you absolutely need to sow tansy in its row spacing, which can significantly help in this problem.
Buckwheat and oats, with their secretion products, can reduce the intensity of germination of white pigweed. Wormwood secretions are dangerous for cucumbers. Thus, in agrophytocenoses, the composition of which was created artificially by human hands, the consequences of allelopathic relationships are very unpredictable.
Animals and plant allelopathy - benefit or harm?
Speaking about the influence of chemical substances of plant origin, one cannot fail to take into account their impact on both animals and humans. Many people have seen coriander bloom in June-July. The beauty is indescribable, and also a lot of benefits for the development of beekeeping. But you shouldn’t succumb to this beauty and spend hours of your leisure time next to him if you don’t want to suffer from headaches and other more unpleasant problems.
Other representatives of the plant kingdom, which at first glance are cute to the eye, act in the same way - wild rosemary, magnolia blossom, eucalyptus leaves and even the well-known lilies of the valley from the front garden next to the house.
An equally strong toxic effect can cause to the human body poisonous sumac, puffy lobelia, even leading to skin burns, irritation, and loss of consciousness. But not all plants negatively affect humans with their chemical secretions. For example, pine or Chinese lemongrass, on the contrary, create a very positive effect.
Allelopathic activity of plants in relation to various types animals are very selective. There are known cases of the stupefying effect of wild rosemary on dogs. Valerian, black root, coriander, and bird cherry serve as powerful repellers for house mice. Even snakes can succumb to chemical attacks from plants such as rue, common peony, and warthog.
Tomatoes have a detrimental effect on aphids, a pest fruit trees and grapes. In addition, aphids are afraid of nasturtium, black nightshade, chamomile, and wild hemp. bed bug does not tolerate the presence of wild rosemary, bugs, milkweed and horseradish. A widely known grain pest, the granary weevil is wary of close exposure to black elderberry and garlic. To everyone who suffers from mosquito bites, it is advised to keep eucalyptus leaves or bird cherry blossoms nearby. Pennyroyal and chamomile have a depressing effect even on the human flea, whose bites can leave stings on the body and transmit the causative agent of the plague.
Almost everyone knows the winter armyworm, which today is considered one of the most common pests of many cultivated crops, does not tolerate the presence of garlic. Bird cherry has the same effect on it, which in turn has the same effect on ordinary housefly. In general, planting bird cherry trees in front of human homes can not only positively transform landscape composition, but also help get rid of annoying synanthropic insects.
The following information will be of interest to those who like to collect in their wardrobes natural fur coats. As in natural conditions, extracts of real lavender, lemon leaves, cypress grass, and shag are successfully used against fur moths. That's why many modern drugs, directed against this delicate pest, are made with a pronounced lavender aroma.
People involved in the professional cultivation of plums, apples and pears could not help but encounter in their activities another well-known agricultural pest - the apple codling moth. Although it may be that they never saw her in person due to her predominantly nocturnal lifestyle, they still had to deal with the unpleasant results of the labors of her larvae. A plant from the Cabbage family, horseradish, wonderfully uses its allelopathic abilities against it.
It’s hard not to remember the pest of cultivated cruciferous plants - cabbage whites. This diurnal butterfly causes considerable losses to the harvest of ordinary white cabbage and cauliflower, and the main peak of its activity occurs in the second half of summer. Among the plants that can chemically suppress its spread and development are rosemary and mint. Therefore, a few mint bushes near the cabbage beds will be more appropriate than ever.
Which gardener has not encountered the problem of garden ants? There probably won't be any. The garden ant sometimes poses a much more serious danger than it seems to us at first glance. Let's return again to competition. We're talking about ants. Often these unwanted guests of our garden occupy the ecological niches of other more desirable inhabitants. In addition, their activity gives rise to another equally serious problem associated with aphids. They, like no one else, carry both the aphids themselves and their eggs from plant to plant, and there are even cases when they drove away from them potential predators comparable in size to them. Not bad, you'll agree. But even against them in nature there is a powerful counteraction from plant nature. It consists of secretions from sage grandiflora, juniper, and rowan. Of course, it is difficult to plant dozens or even hundreds of seedlings of these ant antagonists around the perimeter of your garden plots, but you can still experiment.
The following information will be especially relevant to lovers of indoor flora, which often fall prey to a pest invisible to the naked eye - the spider mite, the size of which is often a fraction of a millimeter. Very often it becomes a faithful companion of rosaries, from which it is not so easy to remove it. Deformed buds, their falling and drying out - this is what awaits the queen of flowers if proper measures are not taken in time. But even in this case, there will be a strong counterbalance to it. An ordinary person copes well with this role. onions. Next to it, any flower plant can be completely safe.
Plant secretions and their mutual influence
Naturally, biologically active substances released by plants will influence each other in different ways. To date, many interesting dependencies of this process have been established.
It is known that another winter crop, rye, has a depressing effect on winter wheat. Oats are able to inhibit peas and lupine. But the oats themselves are subject to negative influence from legume forage plants clover and vetch. Lupine and chickpeas can have a depressing effect on the nation's favorite potato. In addition, chickpeas, a leguminous crop known as “chickpeas,” besides potatoes, negatively affect the growth of cucumbers and tomatoes, eggplants, melons and watermelons, sunflowers, corn and pumpkins. Agree, this is quite a list for one plant.
A common product on our tables, beans, have a direct allelopathic effect on spring wheat, which, in turn, has a similar effect on mustard, flax, hemp and anise. It is advised not to create adjacent crops for sunflower, corn and buckwheat, since these three plants mutually suppress each other with their chemical nature. Although in preparing salads we combine tomatoes and cucumbers in one plate, their natural cooperation is impossible. The secret is that tomatoes are the main antagonists of cucumbers. Onions and beans, tomatoes and turnips act as the same chemical antagonists.
But, since there are negative examples of allelopathy between plants, there must also be positive ones. The most favorable relationship options are between spring wheat and chickpeas, beans and Sudanese, sunflower, tomatoes, potatoes, melons; peas and potatoes. In turn, the latter has a positive effect on barley. Quite good positive results of chemical connections are established between spring wheat and melons, cucumbers, and soybeans. Corn demonstrates a harmonious relationship with chickpeas and beans.
The knowledge that we have regarding allelopathic relationships within agricultural agrocenoses is of considerable value today. The features of allelopathic opposition between cultivated crops and weeds deserve special attention. This provides the basis for further developments of the now popular biological methods protection of agricultural flora, which uses phytogenic secretions, as well as hormones of harmful insects, sexual attractants and a number of other natural substances that can influence pests.
Many have become convinced that adding medicinal plants to the main crop, as well as plants of the Cruciferous family - radish, cabbage, can help in eradicating weeds and insect pests. In addition, they have an antimycotic preventive effect and contribute to soil enrichment.
Pure crops are less productive in terms of yield obtained. Mixed, combined several crops show higher productivity and persistence. But their creation is fraught with a significant problem from which no one is immune - the chemical incompatibility of species that are different in nature.
If you look at the phenomenon of allelopathy from a different angle, then this is nothing more than one of the means of information transfer in the plant environment. Only this information is not verbal-sound, but chemical. This area of knowledge hides many more questions, the answers to which have not yet been established. The influence has not been fully studied environmental factors on the activity and chemical characteristics of these secretions. There are no clear ideas about the size ranges of the ecological valency of each type of organism that is subject to chemical attacks from its neighbors in the field or bed. One thing is clear that productivity, stability and allelopathy are indivisible concepts, the effect of which is only the work of human hands. Proper use the positive and negative effects of plants on each other, the far-sighted organization of crop rotation and neighboring plants can significantly reduce the need for the use of both protective and other agrochemicals.
§ 37-38. Use and protection of subsoil.Soil resources and their useand security
Explain why environmentalists believe that the collection of scrap metal and waste paper is an important environmental activity.
List the non-renewable mineral resources, the reserves of which in the first half of the 21st century. will be more than half exhausted.
How should you plow the soil (or form beds) on a slope to prevent soil erosion? Choose the correct answer:
B) across the slope;
B) along the diagonal of the slope.
Justify your chosen answer.
481 . Choose the correct statement. Soil erosion can be reduced by:
A) planting protective strips;
B) plowing across the slope;
IN) constant maintenance vegetation cover;
D) all of the above factors.
482 . From the list below, select measures that will help stop the erosion process:
transition to low-waste technologies;
organization of nature reserves and reserves;
moldboard-free and flat-cut plowing;
plowing across slopes;
regulation of snowmelt;
combating water and air pollution;
creation of field protection, water regulating and ravine strips;
tillage with soil rotation;
plowing soil;
use of heavy equipment when cultivating soil;
construction of anti-erosion ponds on the tops of ravines accumulating runoff;
construction earthworks;
construction of drainage canals.
484 . Answer the questions:
A. What protects soil from wind erosion? What is the role of perennial grasses in protecting soil from erosion?
485 . According to the FAO (Food and Agriculture Organization of the United Nations), humanity loses (due to leaching, salinization, pollution, etc.) 5-7 million tons of soil per year. If you do not take into account the renewal of soil and the plowing of new territories, calculate how long it will take, under current management, for humanity to lose all the soil cultivated today (about 150 million tons).
486 . Around the world, about 25 thousand tons of soil are washed away every year. In areas where lands are located on steep slopes and are subject to unreasonable exploitation, water erosion, in addition to a sharp decrease in fertility, can lead to dramatic results. Describe which ones.
487 . Use specific examples to prove the connection between the food problem and the problem of soil degradation.
§ 39. Current state"and vegetation protection
488 . Explain why on rivers along which forests have been cut down, the water level is not constant: if there is little precipitation, the level drops significantly; if it rains, water may overflow the banks and flood settlements, fields, etc. Why do floods on forest rivers rarely happen?
489 . Mudflow is a dangerous natural phenomenon; it is a rapid mud flow in the mountains caused by snowmelt or heavy rains. These flows can cause enormous destruction and loss of life. Explain why mudflows are practically absent in places where the population in the mountains is low. Why is the probability of mudflows very high in places where forests are cut down in the mountains and (or) domestic animals are grazed?
Explain why in the spring it takes longer for snow to melt in the forest than on the field. What does this mean for plants; for the hydraulic regime of fields, forests, rivers?
Explain why in national parks and protected areas visitors are only allowed to walk on paths or paths. Why is this requirement especially strict in hilly and mountainous areas?
Choose the correct statement. The Red Book of Russia contains:
B) lily of the valley;
B) lady's slipper;
D) chamomile;
D) St. John's wort.
Name the plant species protected in your area.
Explain why spruce is very sensitive even to runaway ground fires, when moss, pine needles and grass burn on the ground.
Small-leaved linden lives in the forest for up to 300-400 years, in urban conditions - up to 150 years. The branches of pines growing in the city die off at the tops. Answer what is the reason for the poor development of trees in the city.
Environmentalists believe that in the northern regions, forests can only be cut in winter and immediately transported through deep snow. Explain why.
498 . Which reserve can rightfully claim the title of “pioneer of the reserve business in Russia”, since it was in it that 200 years ago S.P. Krasheninnikov, who first described the fir grove in the area of the current lands of the reserve, reported that “... this forest is preserved as a reserve ...? Choose the correct answer:
A) Central Forest Reserve;
B) Belovezhskaya Pushcha;
B) Astrakhan Nature Reserve;
D) Kronotsky Nature Reserve;
D) Barguzinsky reserve.
499 . Explain the meaning of the statement: “One person leaves a trace in the forest, a hundred - a path, a thousand - a desert.”
500 . Thanks to humans, many plant species moved from one continent to another and successfully reproduced there. What properties are usually characteristic of such migrants? Which communities are easier to move into, and which are more difficult, and why? What consequences might such an introduction have for native species?
501 . For centuries in Russia they have been harvesting willow twigs, birch bark, birch sap, birch brooms, willow bark, linden bast, resin (pine resin). Describe the harm these fisheries cause to nature. Indicate the degree of damage to nature caused by fishing. Distribute the crafts according to the degree of harm caused.
502 . Describe the changes in populations of plants with beautiful flowers that may occur as a result of intensive collection of flowering specimens for bouquets.
503 . The famous French researcher of the African Sahara, Henri Lot, describes the transformation of the flourishing region of Niger Air into a lifeless desert in just a few months: “In 1973, a tragedy unfolded. The rainy season started too early and ended suddenly. Since February, the pastures of the northern zones of Air were completely devastated (until this year a lot of people and domestic animals lived here), and the herds had to be driven south, to more favorable places that could not withstand such an influx of livestock. The nomads found themselves in a completely hopeless situation, nothing could save them from the disaster that lay in wait: As a last source of food for the goats, the top branches of acacia trees were cut down, devastating entire valleys, inexorably accelerating the death of trees and thereby contributing to the onset of the desert... Hence the conclusion: It is not the desert that is advancing, but the nomads, by destroying vegetation, contributing to its advance.” What measures do you think need to be taken in drylands to avoid increasing desertification? For example, the Sahara is advancing to the south of the continent along its entire front at an average speed of 48 km per year.
§ 40. Rational useand animal protection
504 . Choose the correct statement. In the Red Book of Russia is:
A) pine marten; d) Amur tiger;
B) ordinary hedgehog; d) brown hare,
c) sable;
Name the species of animals that are protected in your area.
Choose the correct statement. The following is prohibited in nature reserves:
B) pick mushrooms;
C) collect insects for scientific purposes;
D) catch animals for banding.
507. Select from the list the names of animals that were on the verge of extinction, and then saved to humans and became commercial animals;
A) wild boar;
D) sable;
D) European river beaver;
E) stone marten;
G) Przewalski's horse:
H) ermine.
508. Which of the following ways to increase the number of game animals is the most effective? Choose the correct answer.
A) introduction of laws restricting fishing;
B) artificial breeding;
C) improvement of habitat conditions and environmental capacity.
509. Among the listed animals there are those that have already disappeared due to the fault of man (A), those on the verge of extinction (B) and those saved by man from extinction (C).
Using the list provided, fill out the table.
Saiga, dodo (wingless pigeon), kulan, Przewalski's horse, tarpan, bison, bison, Steller's cow, polar bear, Indian rhinoceros, Asian cobra, moose, blue whale, gray whale, sperm whale, gyrfalcon, sea otter , goitered gazelle, tur (wild bull), passenger pigeon, beaver, sable, Amur tiger, elephant tortoise, quagga (zebra), golden eagle, muskrat, snow leopard, small swan, otter, red-breasted goose, Siberian crane, cheetah, bustard. Moa (giant ostrich).
The role of humans in the fate of some animal species
510. Before the advent of man, the steppes were inhabited by a large number of herbivores. On the North American prairies, 75 million bison and 40 million pronghorn antelope grazed, not counting rodents. Eurasian grass bushes eagerly devoured tens of millions of aurochs, wild horses and kulans, 10 million saigas, 5 million gazelles, 20 million marmots, countless hordes of small rodents and large steppe birds: bustards and little bustards. Explain the reasons why the vast majority of these huge herds disappeared from the face of the planet.
511 . In the Russian colloquial language there is a verb “turnut”. To which animal do we owe the appearance of this word in our everyday life?
512 . Indicate the main attractions - the original “emblems” of the following nature reserves: Altaisky, Askania-Nova, Astrakhansky, Barguzinsky, Belovezhskaya Pushcha, Berezinsky, Voronezhsky, Ilmensky, Kandalaksha, Wrangel Island, Sikhote-Alinsky, Khopersky. Main attractions: a storehouse of minerals, lotus, river beaver, sable, eider, Ussuri tiger, bison, polar bear, muskrat, Przewalski's horse.
Sample: Astrakhan Nature Reserve - lotus.