How do desert locusts trigger a food crisis? Is it a threat to our country?

: Since the beginning of this year, from Africa to South Asia, the locust plague has been reported from time to time, all parties are also calling for an active response, and achieved some results. India said at the end of February that the locust plague was almost over. But as a new generation of locust swarms matures into the northern hemisphere summer, locust plagues spread even wider than before. What kind of locusts caused the locust plague, how much damage to the local area, and why is it difficult to control?

of humans and locusts has been around for thousands of years, and locusts that have ravaged East Africa, South Asia and other regions are considered to be one of the world's most destructive migratory pests, desert locusts. Desert locusts are generally found mainly in the warmer, arid deserts and semi-desert regions of northern Africa, the Middle East and southwestern Asia.
most of the time, desert locust populations are low density and exist in the dwarves, when the body of the insect appears a protective color - grass brown. And when population density surges, the mutual stimulation between individuals transforms desert locusts into swarms: the body of the insect turns bright yellow, the near-mature worm turns pink, and the abdomen shrinks, the flight capacity increases, and the food intake increases further. The cause of the surge in desert locust populations is linked to climate change. Two tropical cyclones made landfall in the Arabian Peninsula in May and October 2018.
unusually abundant rainfall has increased soil moisture content, making it more suitable for desert locust eggs to hatch, while vegetation has increased significantly and the hatched larvae have sufficient rations to grow. In such favourable climates, the number of locusts in the next generation will increase 20 times that of the previous generation. Desert locusts have bred freely here for at least three generations due to the region's sparse population and regional tensions.
then locusts began to migrate in search of greater living space, with one heading north toward Saudi Arabia and southern Iran and the other heading south-west across the Channel to the Horn of Africa.
2019, another tropical cyclone made landfall in the Arabian Peninsula and eastern Africa. Warm and humid conditions allow the army of locusts to breed further and spread further a day. Experts estimate that the number of desert locusts in Africa reached hundreds of billions in February. The locusts breed locally, and a new plague of locusts re-occurs a few months later. In addition, locusts have been flying all the way to India, Pakistan and other countries, and even spread from the countryside to cities.
The United Nations Food and Agriculture Organization says each desert locust eats the same amount of food every day as its own weight, while a desert locust swarm of about 40 million locusts per square kilometre, that is, a locust swarm can eat 35,000 people a day.
most effective way to combat locust plagues is to continuously "monitor" the trail of locusts and control them as early as possible before they hatch and grow rapidly. Since the introduction of locust surveillance systems in 1960, the frequency of locust plagues around the world has decreased significantly.
most important means of killing locusts is to spray organophosphate pesticides. The use of such pesticides is likely to damage local ecology and may even threaten human health through contaminated food, but the FAO has to admit that this chemical method is still the main means of directly killing locusts.
locusts themselves have natural enemies, such as pink ostrich, which feeds on locusts and can eat 120 to 180 locusts a day. However, the group of desert locusts will mutate, in the body synthetic release of benzene acetylene, in the face of survival pressure, benzoyl benzene will be converted into highly toxic hydrogen cyanic acid, so that birds such as pink ostrich that prey on them are unwell. As a result, their natural enemies rarely actively feed on the desert locusts in which they live. In addition, the ability of swarm desert locusts to fly up to kilometers and move up to 150 kilometers per day makes it difficult to catch them.
in the face of an incomparable number of locusts, both its natural enemies and human chemical means, have a limited effect on reducing the number of desert locusts. Fao predicted last month that spawning locusts, which are now rampant, would lead to a new generation of more locusts hatching, a wave of destruction that would last for a long time.
, will this wave of desert locusts pose a threat to our country? Experts say the odds are slim.
Wang Zhuran, Director of ecological restoration at the State Forestry and Prairie Administration, said: "Desert locusts have not crossed the barrier of the Qinghai-Tibet Plateau into our country, and as things stand, the probability of desert locusts entering our country is very, very low. "
the southern part of Tibet, the western border of Yunnan and Nepal and other desert locust areas adjacent, do not rule out the possibility of a small number of locusts with the monsoon into our country, but the chance of causing significant harm is very small. In recent years, China's locust monitoring and early warning and control capacity has been improved, drug stocks are also relatively adequate, the relevant departments are paying close attention to the dynamics of overseas locust plague, strictly prevent desert locusts invasion of our country.