Tag: wildlife
Questions Related to wildlife
An American plant, which had become a troublesome waterweed in India is
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Typha latifolia
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Trapa bispinosa
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Cyperus rotundus
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Eichhornia crassipes
Eichhornia crassipes also known with the common name of water hyacinth is a free-floating aquatic plant native to America. It is often considered a highly problematic invasive species outside its native range. E. crassipes reproduces both vegetatively and sexually, but the vegetative reproduction is responsible for the plant’s rapid spread and colonization of water bodies. It occurs through the formation of stolons, which produce daughter plants. This is generally very rapid, if the temperature is high and nutrients are available, it often invades bodies of water that have been impacted by human activities as they often receive large amounts of nutrients. One plant can multiply to cover one acre in a single growing season forming a dense strand. So, with the combination of its free-floating habit, rapid vegetative propagation, and ability to survive on mud during periods of low water levels, E. crassipes has been able to naturalize in a wide variety of aquatic habitats.
Weeds affect the crop plants by
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Killing of plants in field before they grow
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Dominating the plants to grow
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Competing for various resources of crops causing low availability of nutrients
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All of the above
Weeds are nothing but unwanted crops that grow along with the main crop. Thus, they compete with the main crop for sunlight, water, nutrients, and space and thus reduce the resources available to them. In this way, they hamper the growth of the main crop.
................. helps in weed control.
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Mono cropping
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Multi cropping
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Both A and B
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Crop rotation
- Rotating crops with ones that kill weeds by choking them out, such as hemp and other crops, can be a very effective method of weed control.
- It is a way to avoid the use of herbicides and to gain the benefits of crop rotation.
Weeds compete in which of the following with crop plants.
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Sunlight
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Space
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Nutrients
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All of the above
The unwanted plants which grow in field along with the crop plants are termed as weed. They are harmful for the crops as they compete for nutrients, space and sunlight with them.
___________ is an example of weeds.
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Wild oats
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Mango
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Lemon grass
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Oak
The unwanted plants which grow in field along with the crop plants are termed as weed. They are harmful for the crops as they compete for nutrients with them.
Troublesome American water weed found in India is
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Eichhornia
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Trapa
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Cyperus
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Typha
The Eichhornia , commonly known as common water hyacinth, is an aquatic plant native to the Amazon basin, and is often a highly problematic invasive species outside its native range . It grows at an alarming rate and spreads on the surface of the water body. This cut out of the light and it also causes an increase in the oxygen demand. Thus, causing the death of fishes and other aquatic organisms.
Congress grass is
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Cynodon dactylon
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Digitaria purpurea
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Cymbopogon citratus
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Parthenium hysterophorus
Congress grass is the common name for Parthenium hysterophorus . It is a species of flowering plant in the aster family, Asteraceae.
Which one is a troublesome weed of agricultural fields?
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Chenopodium album
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Cyperus rotundus
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Parthenium hysterophorus
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Eichhornia crassipes
Parthenium hysterophorus is commonly called as congress grass or gajar ghass .It is a species of flowering plant in the aster family, Asteraceae. It is native to the American tropics. This weed is equally dangerous for all flora and fauna. It is highly dangerous for humans. It utilizes most of the nutritious substances from soils, thus converting fertile ground into unfertile ones.
Agent Orange consisted of
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2,4 - D
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2,4,5-T
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Dioxin as contaminant
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All the above
- Agent Orange refers to a herbicide mixture which was used by the U.S. military during the Vietnam War and it contained a dangerous chemical contaminant called dioxin.
- The active ingredient of Agent Orange was an equal mixture of two phenoxy herbicides – 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5 trichlorophenoxyacetic acid (2,4,5-T) and it also contained traces of the dioxin 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).
- So the correct option is ' All of the above'.
Temperate forests occur in India in
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Indo-Gangetic plains
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Himalayas
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Eastern India
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Southern Peninsula