Even before canaries(特高频噪声) were brought into coal mines to alert workers to the presence of poisonous gas, birds were giving us early warning calls signaling the Earth"s deteriorating environmental health. Global bird populations have shrunk by up to 25% since preagricultural(农业社会前的) times. Over the past 300 years, farmland has expanded from six percent of the Earth"s surface to nearly 33%.Today, three quarters of threatened bird species depend on forests as their principal habitat; each year, however, some 13,000,000 hectares of forests are destroyed, an area the size of Greece. Nearly half the woodlands lost are relatively undisturbed primary forests that are home to a number of sensitive birds and other creatures.Direct exploitation, including hunting for food and capture for the pet trade, is the second greatest danger after habitat loss, while next is the intentional or accidental introduction of non-native species. As people travel to all parts of the globe, so too do the pests and pets that prey on, out-compete, or alter the habitat of native wildlife.Pollution poses an additional risk, affecting 12% of the threatened bird species. In addition to direct poisoning from fertilizer and pesticide applications, runoff of chemicals contaminates the wetlands that migrating waterfowl rely on. Persistent organic pollutants accumulate in the food chain and can lead to deformities, reproductive failure, and disease in birds.Worldwide, one-third of plant and animal species could become extinct by 2050 as a result of climate change, a relatively new threat. Global temperature spikes have brought severe alterations to the migration, breeding, and habitat ranges of some birds.In addition to these looming dangers, seven percent of threatened bird species are at risk from incidental mortality. A rapid decline in seabird populations over the last 15 years corresponds with the growth in commercial longline fisheries. In Europe, Central Asia, and Africa, electrocution on power lines has caused the mass mortality of raptors. Moreover, countless birds die each year from collisions with windows, the number-one cause of U.S. avian mortality.If birds disappear, so do the economically valuable services they provide. Preventing the extinction of additional bird populations depends largely on protecting the world"s remaining wild spaces and preserving the health of our natural and altered ecosystems.Reports that the ivory-billed woodpecker, long thought to be extinct, is still with us thrilled bird watchers and others, but this sort of second chance seldom occurs in nature. Even with continued habitat protection, once wildlife populations drop dramatically, a rebound is far from guaranteed. Without stabilizing climate and human numbers, putting fences around all the parks in the world will not lie enough to protect threatened species.Which of the following statement has nothing to do with the drastically declining number of birds?
A.Loss of forests that are home of birds.B.Toxic chemicals that may cause diseases to birds.C.Their habitat area in Greece that has been destroyed.D.Animals from other continents by the process of globalization.
相关标签: 农业社
公共事务是:()
A、人类社会产生之后就有了
B、人类进入农业社会后产生的
C、文字产生之后出现的
D、现代社会产生的
E、工业革命之后产生的
材料一:某教授在谈到东西方文化差异时形象地讲到:西方文化是桥牌文化,而东方的文化是围棋文化、麻将文化。美国人打桥牌强调的是强强联合,日本人下围棋强调的是一致对外,中国打麻将崇尚的是自摸。看住上家,防住下家,自己和不了牌,也休想让别人和。中国文化源于农业社会的生活方式,强调等级与和谐;而希腊文明则对狩猎和捕鱼的依赖较大,强调个人特征。材料二:汉字是中华文化之瑰宝,也是中华民族的灵魂,更是开启数千年华夏文明巍巍大厦的金钥匙。然而信息化时代,电脑、手机等智能化打字功能的普及,造成了国人手写汉字水平明显下降,产生了一批批提笔忘字、频写错字、写不好字、不会写字、不想写字的新型“文盲”。2013年8月2日,《中国汉字听写大会》在央视成功首播后,在全社会迅速掀起了一股手写汉字的热潮。材料三:《孔子家语》:“与善人居,如入兰芷之室,久而不闻其香,则与之化矣。与恶人居,如入鲍鱼之肆,久而不闻其臭,亦与之化矣。”人的文化素养是多方面的,其中具有方向性作用、处于核心地位的是( )。
A、社会科学素养
B、自然科学素养
C、社会公德、职业道德、家庭美德
D、世界观、人生观、价值观
1958年6月12日,《人民日报》报道:河南省遂平县卫星农业社2.9亩小麦试验田亩产达3530斤。这篇浮夸报道的出现反映了“左”倾错误的泛滥。“左”倾错误出现的的原因是①中共八大的指引 ②对我国所处的发展阶段认识不足③对如何建设社会主义缺乏经验 ④忽视了客观的经济规律
A.①②③
B.②③④
C.①②④
D.①③④
()不属于农业社会所出现的技术创新。
A、铁器的出现
B、纺织的出现
C、农业工具的发展
D、陶器的出现
A.状态B.尺度C.标准D.节奏