Americanscientistsaythattheybelievetreescanwarneachotherofdangerreleasingchemicalsintotheair.__1__ ThetheorywasannouncedbytheNationalScience__2__ FoundationistheresultofstudiescarriedoutbyscientistinthestatesofWashingtonandNewHampshire. Thescientistssaidtheyfoundthatwhentreesareagainstattackbydiseaseorinsects, nearby__3__ treestakethesameoffensiveactionsasthetrees__4__ beingattacked. Andtheysaiditappearsthatthetreesbeingattackedmayproduceandsendoutchemicalstowarntheothertrees. AUnitedNations'reportsaysAsiancountriesarefacedmajorenviron-__5__ mentalproblems. ThereportreleasedinBangkoksaidthatpartsofChina, India, Iran, Afghanistanand Pakistanwerethreatenedbyman-madeandnatural__6__ eventsthatturnproductivelandintodeserts. IsaidthemostseriousthreatagainsttheareaistherapidexpansionofAsia'srainforests, orwoods, especially__7__ inMalaysia, thePhilippineandThailand. Thereportsaidthereductioninwoodsareashavealreadyledto __8__ increasedflooding, watershortagesinthedryseasonsandthelossoffarmlands. AtopUNofficialsaidthatasmuchas 70% ofthewoodsinAsiawouldbegonein__9__ 20 yearsunlessactionsaretakennowtosaveit.__10__