This year's weather is really too abnormal, originally June to October is the Flood Season of the Yangtze River, 80% of the precipitation throughout the year is concentrated in this period, especially in July and August is the main flood season of the Yangtze River, in previous years, the main problem facing the Yangtze River Basin is flood control, but this year it has become drought resistance.
This year, the precipitation in the Yangtze River Basin is scarce, and the precipitation since July is the lowest in the same period of history since 1961, 4.5% less than the same period in previous years, the number of high temperature days in most areas is more than 20 days, and the number of high temperature days in the middle and lower reaches is more than 30 days; in some areas, there are more than 20 days of less rain, and more than 40 consecutive days of less rain in some parts of Hunan.
But on the other hand, this year, the Yangtze River Basin has abnormally high temperatures, the maximum temperature in the local area has even reached 45 ° C, affected by high temperatures, the evaporation of rivers and lakes is large, so that the water level of many rivers and lakes in the Yangtze River Basin has declined, and the area of Dongting Lake has shrunk.
The water surface of Dongting Lake has shrunk, resulting in the place that should have been the lake area becoming a "grassland".
The change of the water level of Dongting Lake also affects the local animals and plants, and the change of the lake area to grassland provides convenience for a small animal, which is a mouse.
There is a kind of mouse living in the Dongting Lake area: the oriental vole (in addition to the oriental vole there are other mice), compared to the general mouse, its tail is relatively short, the general mouse tail and body length is almost the same, but the tail of the oriental vole is shorter than 1/2 of the body, they are fat, usually live in the middle and lower reaches of the Yangtze River, Dongting Lake area is one of their main habitats.
Oriental voles like to live in low-lying, soft soil, lush grass environment, of which the lake beach grassland is their best habitat, where they feed on the reeds in the lake beach, moss grass, etc., but this does not mean that they do not eat other vegetation, researchers found that the oriental voles feed both selectively and mobilely, that is, to see what to eat.
The decline in the water level of Dongting Lake has led to the transformation of the lake area into grassland, which is a good thing for the oriental voles, and it simply provides convenience for their survival and reproduction.
Oriental voles have a very strong reproductive ability, 1 year can breed 2-4 litters, each litter of 4-11 cubs, cubs can be sexually matured after 2 months of birth, into the production army. A pair of oriental voles can produce 100-200 offspring per year.
Because the rate of reproduction is very fast, as long as you give the oriental voles some time, their populations can grow exponentially and eventually explode. The Dongting Lake area will become a paradise for rats.
At this time, the rats have not yet shown a destructive side, after all, they eat grass in the Dongting Lake area, and the real harm is that when the dry season is over and the flood season comes, there may be a rat infestation in Dongting Lake at this time.
Let me say more here that if the water level of Dongting Lake suddenly rises when the flood season comes, there will generally be no rat infestation, because many rats will be flooded before they can escape and cannot be disturbed.
Most of the formation of rat infestations is due to drought in the previous year, which makes the Dongting Lake area become grassland, leaving sufficient food sources and activity space for oriental voles, so that the survival rate of young people increases and the population grows explosively; In the coming year, the lake rises, but the rate of rise is slow, at which time the oriental voles will be driven by the flood to the outside of the lake area, the density will increase, and the number will increase.
At this time, the living space of the rats is reduced, the rats are hungry, and the hungry rats may break through the Dongting Lake area, jump over the embankment, come to the human living area, destroy the farmland, and eat indiscriminately.
In 2007, Dongting Lake was drought for 9 consecutive months, giving the Oriental voles sufficient activity space and breeding time, and the rate of rising water level during the flood season was relatively slow, although it flooded the homes of the Oriental voles, but also left sufficient migration time for the Oriental voles, resulting in a serious infestation of dongting lake rats.
In the place where the rat infestation was most serious, a rat-proof embankment was built along the Dongting Lake embankment, and a 30-60 cm anti-rat ditch was dug under the embankment, resulting in too many rats, rats quickly filled the anti-rat ditch, and there were still a large number of rats breaking through the siege, endangering farmland and buildings. At that time, the residents of the Odori Lake area hunted about 10 tons of rats every day, which can be said to be very serious.
The 2007 Dongting Lake rat infestation also sounded the alarm for the Dongting Lake drought, the drought will certainly provide ample food sources and habitat for rats, if the drought continues until next year, and the water level slowly rises during the flood season in the coming year, the Dongting Lake rat infestation may make a comeback.
How can I prevent rat infestation?
Since the water level of Dongting Lake has dropped, which has facilitated the breeding of rats, what are the ways to prevent rat infestation?
On the one hand, it is necessary to protect the natural enemies of mice, and there are actually many natural enemies of rats, such as: king snakes, water snakes, black-browed snakes and other snakes, there are also owls, falcons and other birds of prey, as well as cats, mink, weasels and other small beasts of prey.
It's just that the natural enemies of rats do not reproduce as fast as rats, and when rats suddenly erupt, natural enemies are often too late to be eliminated, and a new batch of rats begins to participate in breeding.
On the other hand, it is necessary to do a good job of prevention in advance, and the residents of Dongting Lake will often build anti-rat walls and install electronic rat exterminators in advance before the rat outbreak.
Also, the current market of potent rat poison has been banned, for example: rat poison is strong, this is mainly because most of the potent rat poison in the rat body has residues, rats eat rat poison will soon die, but the rats for food cats, dogs, birds of prey will also die because of eating highly toxic rats, in 2007, in order to deal with rats, Binhu Village put a large number of potent poison, resulting in more than 1,000 cats left in the village.
The current rat poison is a chronic poison with less ecological impact, the rat will not die immediately after eating, it will take effect after 3-5 days, and the remains of the dead rats will not cause secondary poisoning even if they are eaten by predators.
In addition, if you can, you can make the water of Dongting Lake rise overnight, which is the best way to kill rats, so that the rats have no time to escape, and a large number of rats are buried in the lake, becoming food for fish, and avoiding rat infestation.
In any case, Dongting Lake entered the dry season in advance, which has a great impact on the local ecology, in addition to preventing various losses caused by drought, it is also necessary to be vigilant against rats and avoid the occurrence of rat infestations.
#When will the sustained high temperature in the south alleviate the ##鄱阳湖, Dongting Lake "thin into lightning" ##洞庭湖 #