Check with your local council about local flood plans or records which detail problem areas. Ask authorities about relocation routes and centres. If your area is flood prone consider alternatives to carpets. Prepare an emergency kit. Prepare a household flood plan. What should you not do during a flood? Drive through floodwaters.
Use electricity in a flooded home. Get in the flood water. Handle wild animals in the flood water. Ignore flood warnings. Neglect to assemble a flood safety kit. Leave utilities on and plugged in when you evacuate. Dress improperly. What should we do after flood? After a Flood. Listen for news reports to learn whether the community's water supply is safe to drink.
Avoid flood waters; water may be contaminated by oil, gasoline, or raw sewage. Avoid moving water. Be aware of areas where flood waters have receded. Stay away from downed power lines, and report them to the power company.
Should you swim in flood water? Don't drive in flooded areas — turn around, don't drown! Floodwater can pose a drowning risk for everyone— regardless of their ability to swim. Swiftly moving shallow water can be deadly, and even shallow standing water can be dangerous for small children.
Always follow warnings about flooded roads. What are the warning signs of a flood? Common warning signs include intense rainfall, dam or levee failure as well as other events such as slow moving tropical storms and early snow melt can all contribute to flooding , whether you live in a flood zone or not.
What are interesting facts about floods? No region is safe from flooding. Flash floods can bring walls of water from 10 to 20 feet high. A car can be taken away in as little as 2 feet of water. To stay safe during a flood, go to the highest ground of floor possible. It is very difficult to link a flood to the cause of tree death years later.
Trees are more likely to be damaged by flooding during the growing season than by flooding during the dormant season. Trees are most susceptible to flood damage in late spring just after the first flush of growth. Tree species begin their spring flush at different times so the timing of a flood influences the species that are likely to be damaged.
If trees are flooded by heavy rain or snow melt in late winter or early spring when the trees and shrubs are not actively growing, and the water recedes before growth begins, flooding usually is not a problem. Most tree species can withstand one to four months of flooding during the dormant season.
When flooding occurs during the growing season, especially during warmer weather, one to two weeks of flooding can cause major, long-term damage to sensitive trees and shrubs, even death with some species. Some species can survive as long as three to five months in flooded situations. A long-duration flood, especially during the growing season, may decrease height and diameter growth of tree species that are intolerant of flooding.
But height and diameter growth may increase for flood tolerant species. Water covering the soil reduces the supply of oxygen to tree roots.
Roots must have oxygen to survive and grow. A well-drained soil for trees and shrubs allows water to drain percolate at a rate of one inch per hour.
To test the drainage rate of your soil, dig a hole 24 inches deep, fill with water, let it drain completely and then fill once again. If the inch deep hole drains within 24 hours, this well-drained soil is considered close to optimum for most landscape trees and shrubs.
A poorly-drained soil will take more than 24 hours to drain a 24 inch deep hole, but there are degrees of poor drainage. A soil that takes hours to drain is not nearly as bad for trees as a soil that percolates at a rate of 24 inches in seven to ten days.
Flooding increases the pH of acid soils and decreases the pH of alkaline soils. Tree species vary in their pH tolerance. Flood waters may contain chemicals from urban areas or agricultural fields that may be harmful to trees when absorbed by their roots. Strong currents, waves or suspended particles may cause soil around the base of trees to be washed away, exposing their roots. Exposed roots can stress trees and make them more vulnerable to being uprooted or broken by wind windthrow or blowdown.
Ice flows and debris carried by rushing waters can remove bark and damage tissues. Such wounds may then be subject to wood stain and decay organisms. Flood waters that cover foliage on lower branches will interfere with photosynthesis and gas exchange, leading to death of those branches. Stem boring insects are the major insect group of concern. The most common stem borers are beetles, either adults or immature larvae depending on the species. Other stem borers which may damage trees are a few moth or woodwasp larvae.
Stem boring insects can be further divided into phloem borers and wood borers. Phloem borers include bark beetles and many of the metallic wood-boring beetles. These two layers are important in food and water transport and, if significantly damaged, can kill trees. Wood borers may spend some time in the phloem layer, but generally tunnel deeper and feed in the wood of tree stems or branches. This tunneling is not usually a serious impediment to tree survival, but it can significantly reduce the quality of any eventual wood products.
Wood borers, however, weaken stems, which may lead to breakage during ice, wind or snow storms. See Flatheaded borers and Emerald ash borer. Numerous small holes in the bark are a common symptom of stem borers. Insect entrance holes may have pitch, sap or sawdust exuding from them.
Exit holes are generally very clean and may be round, oval or D-shaped. Removing the bark will expose larval tunnels on the wood surface. Removing bark on living trees will damage a tree, so do this only on dead trees or low quality trees to test for the presence of stem borers.
Prevent additional wounding or root damage to trees. Wounds create stress and attract many insects. Sanitize areas by removing and destroying large broken limbs and dead trees. This material may act as breeding sites for stem-boring insects which may later infest surrounding live trees. Increase tree vigor through light fertilization treatments and watering if soil conditions become excessively dry during the two or three years following flooding.
Insecticides rarely help control stem borers. They should be used only for high value trees and following the recommendations of a professional entomologist, arborist or forester. Stem borer insecticides are applied to the tree bark as a protectant, application must be made before infestation.
It is unknown whether leaf-feeding caterpillars or sucking insects scales and aphids will become more of a problem following flooding. Plant stress can alter the biochemistry of trees making nutrients and sugars more available to insects feeding on leaves or sap. This could increase survival of these insects and increase their population size. Outbreaks of caterpillars or scales and aphids could further increase stress levels on trees severely weakened by a flood.
Control of these insects should be considered a priority on high value trees for one to three years after a flood. This may require application of insecticides following label directions. There are too many potential insect pests and tree species to list all possible sources of insect damage, but the following tree species are notorious for insect attacks following stressful periods:.
Hickory bark beetle Scolytus quadrispinosus. Several diseases may weaken or kill trees following flooding. Armillaria root rot is also known as shoestring root rot. There are hundreds of species of Armillaria fungi. It can cause wood decay, growth reduction and death to hundreds of tree species, but commonly infects and kills trees already weakened by other factors. Although drought is usually considered the precursor to Armillaria infections, flooding has been implicated in Armillaria root rot infections in oak, chestnut and larch.
Symptoms of Armillaria infection include leaf chlorosis yellow then brown , defoliation, reduced leaf and shoot growth, dieback, and death. On most conifer species, lower stems usually are somewhat enlarged and exude large amounts of resin. Broadleaved trees may develop sunken cankers covered with loose bark or bark infiltrated with gum.
Removing the bark will expose white mycelia fans on the wood surface or black, shoestring-like rhizomorphs attached to roots. Most of the damage caused by a hurricane is obvious—roofs ripped off buildings, homes flooded, downed electrical lines.
But long after the eye of the storm has passed, big storms can continue to spread disaster. Hurricane Irma gained global attention when it wiped out the small island of Barbuda, rendering it uninhabitable for the first time in a decade.
Haiti, which sits roughly miles northwest of Barbuda , missed the worst of the storm. Cholera is an infectious disease, the most notable symptom of which is severe diarrhea. This can lead to dehydration and, if left untreated, death. People catch it by consuming water or food contaminated with the bacterium Vibrio cholera.
Thanks to modern sanitation—treated drinking water and sewage systems—the disease is rare in the United States. These days the few cases that show up within our borders each year are usually brought in by people traveling from other countries.
In countries like Haiti that still struggle to provide this kind of infrastructure, increased rainfall spreads cholera by moving dirty water into once clean rivers and wells. Testing is rare in this region of the world, so a water source that was safe to drink before the hurricane can become dangerous afterwards—and imbibers are none the wiser until someone falls ill.
There are lots of interventions a country can try to implement.
0コメント