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        托??荚囌骖}:2013.3.30托??荚囬喿x機經(jīng)

        字號:


            閱讀:
            第一篇:Agricultural Management in the Late Aztec society
            版本一:
            一個什么地區(qū)的農(nóng)業(yè)問題。講了農(nóng)業(yè)上三個問題,假設(shè)是ABC吧。A是家庭就可以完成。B是灌溉,建設(shè)起來工程大,維護起來很費力,是政府介入的,幾個城市還是分別獨立的不影響。C是既有A的特點又有B的特點(這句話有改寫題,改寫成:C像B一樣建設(shè)和維護起來很麻煩需要政府的力量,也像A一樣后期可以家庭就可以實現(xiàn)不需要政府的力量)。
            版本二:
            第一篇:mesoamerica的農(nóng)業(yè),講那個地方的人農(nóng)業(yè)很密集,但都是各戶耕種就足以自足了,后來又有政府神馬的公眾機構(gòu)涉入,建造和maintain河道(好像是河道)
            Aztec Agriculture
            Farming provided the basis of the Aztec economy. The land around the lakes was fertile but not large enough to produce food for the population, which expanded steadily as the empire grew. To make more land suitable for farming, the Aztec developed irrigation systems, formed terraces on hillsides, and used fertilizer to enrich the soil. Their most important agricultural technique, however, was to reclaim swampy land around the lakes by creating chinampas, or artificial islands that are known popularly as “floating gardens.” To make the chinampas, the Aztec dug canals through the marshy shores and islands, then heaped the mud on huge mats made of woven reeds. They anchored the mats by tying them to posts driven into the lake bed and planting trees at their corners that took root and secured the islands permanently. On these fertile islands they grew corn, squash, vegetables, and flowers.
            Aztec farmers had no plows or work animals. They planted crops in soft soil using pointed sticks. Corn was their principal crop. Women ground the corn into a coarse meal by rubbing it with a grinding stone called a mano against a flat stone called a metate. From the corn meal, the Aztec made flat corn cakes called tortillas, which was their principal food. Other crops included beans, squash, chili peppers, avocados, and tomatoes. The Aztec raised turkeys and dogs, which were eaten by the wealthy; they also raised ducks, geese, and quail.
            Aztec farmers had many uses for the maguey plant (also known as the agave), which grew in the wild to enormous size. The sap was used to make a beerlike drink called pulque, the thorns served as needles, the leaves were used as thatch for the construction of dwellings, and the fibers were twisted into rope or woven into cloth.
            Aztec Society
            Agriculture
            The pre-conquest Aztecs were an empire that prospered agriculturally, and they did so without the wheel or domestic beasts of burden. They had four main methods of agriculture that were quite successful. The earliest, most basic form of agriculture implemented by the Aztecs is known as “rainfall cultivation.” The Aztecs also implemented terrace agriculture in hilly areas, or areas that could not be used for normal farming. Terracing allowed for an increased soil depth and impeded soil erosion. The terraces were built by piling up a wall of stones parallel to the contour of the hillside. Dirt was then filled in, creating viable, flat farmland. There were three types of terrace agriculture, each one used for specific circumstances. The three types were; hillslope contour terraces (steeper slopes), semi-terraces (gentle slopes, walls were made with Maguey plants rather than stones), and cross-channel terraces. Terracing was used mostly in the highlands of the Aztec empire. The Aztecs invented the wheel for the use of their children but not for them.
            In the valleys of the empire, irrigation farming was used. Dams diverted water from natural springs to the fields. This allowed for harvests to be successful on a regular basis. The prosperity of a field was not dependent upon the rain. Irrigation systems had been in place long before the Aztecs. However, they built canal systems that were longer and much more elaborate than any previous irrigation systems. They even managed to divert a large portion of the Cuauhtitlan River to provide irrigation to large areas of fields. The network of canals was a very complex and intricate system.
            In the swampy regions along Lake Xochimilco, the Aztecs implemented yet another method of crop cultivation. They built what are called chinampas. Chinampas are areas of raised land, created from alternating layers of mud from the bottom of the lake, and plant matter/other vegetation. These “raised beds” were between 2 and 4 meters wide, and 20 to 40 meters long. They rose about 1 meter above the surface of the water, and were separated by narrow canals, which allowed farmers to move between them by canoe. The chinampas were extremely fertile pieces of land, and yielded, on average, seven crops annually. In order to plant on them, farmers first created “seedbeds,” or reed rafts, where they planted seeds and allowed them to germinate. Once they had, they were re-planted in the chinampas. This cut the growing time down considerably.
            第二篇:日本氣候
            版本一:
            日本的氣候,受兩氣流的影響,西伯利亞氣流和啥,一冷一暖,有圖。第一段的題問哪個不是西伯利亞冷空氣帶來的影響。
            后面說氣候?qū)r(nóng)業(yè)(冬天冷不好啦夏天多雨好啦),對居住的影響。
            最后一段說two million啥以來,人們居住從south向north了,導(dǎo)致農(nóng)業(yè)產(chǎn)量不太好(這里有題,我貌似選了人們居住從south向north了,where plants 也種的好,差不多意思)
            版本二:
            日本的氣候,還給了圖,先是說西伯利亞冷空氣的影響,后來什么降水和臺風(fēng)還是什么風(fēng)之類的也有影響,再然后講到氣候?qū)θ毡巨r(nóng)業(yè)的影響,南北不一,一邊好一邊不好,具體也忘了那邊好那邊不好了,反正有區(qū)別(這里有題,還不止一道,細節(jié)題和排除題),然后日本人就都挪窩到東北了貌似,因為氣候和其他因素限制農(nóng)業(yè)發(fā)展。
            本篇解析請直接回顧2013年1月26日的閱讀解析的第二篇。
            第三篇:動物選擇棲息地
            版本一:
            第一段集合了好幾個詞匯題。
            動物選擇habitat。第二段有一個人做了一個實驗(有題問為什么提到這個實驗,我選為了挑戰(zhàn)那一段第一句的說法)中間提了光照什么的,也有實驗,結(jié)果鳥兒調(diào)整了自己的。。。(作息??)
            后面還說了遷徙時female鳥不想和male競爭就飛得遠一點(有題為啥female飛得遠)。
            版本二:
            動物選擇棲息地,受多種因素控制,有一種叫photoperoid,指光照時間,講了鳥因光照長短不同而選擇不同棲息地的實驗,還有避免競爭(有題,female不想和male競爭就飛得遠遠兒的),然后還有predator的威脅。就這三個了貌似。
            Habitat Selection
            Charles Darwin visited the Falkland Islands in the South Atlantic during his 1831-1836 globe-girdling expedition in H.M.S. Beagle. He reported: "Two kinds of geese frequent the Falklands. The upland species (Anas magellanica) is common, in pairs and in small flocks, throughout the island.... The rock goose, so called from living exclusively on the sea-beach (Anas antarctica), is common both here and on the west coast of America, as far north as Chile." The names of the geese have since changed (to Chloeophaga picta and C. hybrida, respectively), but these, two closely related species each live, as Darwin described, in a different range of habitats.
            Ornithologists are interested in answering two major questions about habitat selection -- what determines the range of habitats in which a species occurs, and how does each individual determine when it's in an appropriate habitat? The first question is evolutionary: how has natural selection shaped habitat choices? The second is behavioral: what cues does a bird use in "choosing" its home? We put choosing in quotes to emphasize the presumed absence of conscious choice. Indeed, some ecologists employ the term "habitat use rather than "habitat selection" to avoid the connotation of birds making deliberate decisions among habitat alternatives.
            Birds are nearly ideal subjects for studies of habitat selection, because they are highly mobile, often migrating thousands of miles (and in the process passing over an enormous range of environments), and yet ordinarily forage, breed, and winter in very specific habitats. Indeed, the lives of small migrant songbirds are replete with habitat choices -- where to feed, where to seek a mate, where to build a nest, where to stop to replenish depleted stores of fat when migrating, and so on. Choices can be so finely tuned that often the two sexes of a species use habitats differently. In grassland, male Henslow's Sparrows forage farther from the nest than females; in woodlands, female Red-eyed Vireos seek their food closer to the height of their nest (10-30 feet), and males forage closer to the height of their song perches (20-60 feet).
            Many studies have demonstrated the special habitat requirements of different species. Belted Kingfishers choose nesting sites at those points along streams where particular kinds of riffles shelter fish. Broad-tailed Hummingbirds in the Colorado Rockies select nest sites under a canopy of conifer branches; the nighttime microclimate is warmer there, and the chance of daytime overheating is less. Red-cockaded Woodpeckers settle in woodlands offering the tall, old pines infected with heartwood fungus that their clans require for nests. Spotted Owls may require a habitat that includes cool spots in deep canyons in which to roost, and Ferruginous Hawks select open country with low cover and suitable perch sites.
            Some groups of birds are much more habitat-specific than others. Our wood warblers (tribe Parulini) are generally much more tied to certain habitats, and tend to restrict the height at which they forage much more closely than do many Old World warblers (family Sylviidae). In most cases the latter do not show the sort of specialization that restricts the Pine Warbler largely to pine and cedar groves, and separates and Ovenbird and Black-and-white Warbler (which occur in a wide variety of vegetation types) by foraging preference. The former searches the ground and the latter gleans tree trunks and limbs. The behavioral differences between the superficially similar New World and Old World warblers indicate that evolution has, to a degree, genetically programmed habitat choice.
            But the habitat preferences that evolution has programmed into a species are not cast in concrete. Local populations may respond either genetically or behaviorally to special conditions by changing the habitats they occupy. For instance, in a classic study ornithologist Kenneth Crowell compared the ecology of Northern Cardinals, Gray Catbirds, and White-eyed Vireos in eastern North America and on the island of Bermuda. On the mainland all three species prefer forest edge sites, and the catbird and vireo tend to select habitats near water. On Bermuda, which is largely dry and devoid of forest, dense populations of all three species are found in areas of scrub.
            Similarly, ecologist Martin Cody found that when drought greatly reduced the availability of insects in an Arizona pine-oak woodland, the density of birds was also greatly reduced and the composition of the bird community altered. Those species typical of more moist, higher elevation habitats as well as pine-oak woodland (such as Painted Redstarts, Western Wood-Pewees, and Pygmy Nuthatches), departed. In contrast, species normally found in drier, lower elevation habitats such as mesquite scrub (including Ash-throated Flycatchers, Lucy's Warblers, and House Finches), chose to move into the now more and woodland.
            Avian habitat selection is a vast topic in part because both amateur and professional students of birds have accumulated an enormous body of information on which birds live where, and how they operate in their environments. But detailed observations can still add to our understanding of habitat selection -- especially observations of bird behavior made when habitats are being altered either by "natural experiments" such as droughts and insect outbreaks or by human activities.