文档介绍：一、自然、生态、(1)Environmental/water/air/noisepollution         (2)Resourcesexhaustion(3)Wildlifeextinction(4)Endangeredspecies(5)Naturalhabitat(6)Reserveareas(7)Sand/duststorm                            (8)Clear-cutting/deforestation(9)Overfishing(10)Overgrazing(11)Soilerosion                              (12)Waterandsoilconservation(13)Desertification                            (14)Naturaldisaster(15)Floodthreat                              (16)Firehazard(17)Storm/tempest                            (18)Blizzard(19)Drought                                 (20)Famine(21)Disruptionofecologicalbalance(thebalanceofecosystem)(22)Eruptionofvolcanoes                    (23)Earthquake(24)Avalanche                                (25)Landslide(26)Hurricane                                (27)Shortageofwaterresources(28)Shortageoffreshwater                  (29)Harmfulchemicals(30)Poisonous/toxicgases                    (31)Carbonmonoxide(32)Urbansmog                              (33)Industrialwaste(34)Hazardousnuclearwaste                (35)Radioactivepollutants(36)Wastegassentofffromautomobiles     (37)Caremissionstandard(38)Non-biodegradablematerial                 (39)Throw-awaylunchbox(40)Recyclableproduct                        (41)Renewableresources(42)Conservenaturalresources                  (43)Plasticbags(44)Greenhouseeffect                         (45)Globalwarming(46)Acidrain