Yes the weaker it is the more easy it is to prey on
Answer:
A biological community in which association takes place between the organisms and their physical surroundings is termed as an ecosystem. It can also be defined as an association between the nonliving and living components found within the environment. A particular geographical region, which is specified for the species thriving within it is known as a biome.
A branch of science, which deals with the natural procedures that comprise fire within an ecosystem and the ecological influences it imparts, the association between the biotic and the abiotic constituents of an ecosystem with the fire, and the role played by fire within an ecosystem is termed as a fire ecology.
Different kinds of ecosystems like savanna, prairie, coniferous forests and chaparral have originated by the contribution of the fire, which plays an essential role in the renewal and vitality of the habitat. Different kind of plant species needs the assistance of fire to establish, to reproduce, or to germinate. In case, if the suppression of wildfire takes place, it will eventually result in the eradication of various plant species and the animals that rely upon them.
DDT stands for dichloro-diphenyl-trichloroethane. The first kind of synthetic/artificial insecticides came into use in the 1940s. The earlier usage of DDT include: a) Killing of malarial vectors, b) Combatting Typhus and other insect borne human diseases, c) As a pest control in crops d) as a pest control in garden, live stock production and even at homes.
The negative impact of DDT could be felt for the first time when the pests that were earlier killed by use of DDT have now become pesticides resistant. In the 1950s in USA, the regulatory measures were adopted to reduce the usage of DDTs as its effects as a pesticides were no more long significant and also it was creating detrimental physical and psychological impacts on the human and environment.
It was in 1972 that the U.S. Environmental Protection Agency cancelled the order for banning the usage of DDT based on the adverse impact it produced on the environment, human and other life forms. Since then continuous studies are being conducted to analyse the impact of DDTs. In some later years it was established that DDT is the cause of producing tumors in liver.
Some of the common negative impacts produced by DDT as per the U.S. Department of Agriculture :
a) The non destructive nature – DDT can not be destroyed and thus it remains persistent in the atmosphere
b) It attacks the tissues of living organisms especially the animals and humans ( fatty tissue)
c) It can penetrate the atmosphere to deeper extent.
Now as per the current stuation, The use of DDT is controlled and other alternatives of pest control organisms is being deduced. As per the treaty of Stockholm Convention on POPs (Persistent organic pollutants) , usage of DDT for malarial control is justified but it puts a restrictive use of DDT as pesticides in other areas.