首页
登录
职称英语
There are both great similarities and considerable diversity in the ecosyste
There are both great similarities and considerable diversity in the ecosyste
游客
2025-01-19
31
管理
问题
There are both great similarities and considerable diversity in the ecosystems that evolved on the islands of Oceania in and around the Pacific Ocean. The islands, such as New Zealand, that were originally parts of continents still carry some small plant and animal remnants of their earlier biota (animal and plant life), and they also have been extensively modified by evolution, adaptation, and the arrival of new species. By contrast, the other islands, which emerged via geological processes such as volcanism, possessed no terrestrial life, but over long periods, winds, ocean currents, and the feet, feathers, and digestive tracts of birds brought the seeds of plants and a few species of animals. Only those species with ways of spreading to these islands were able to undertake the long journeys, and the various factors at play resulted in diverse combinations of new colonists on the islands. One estimate is that the distribution of plants was 75 percent by birds, 23 percent by floating, and 2 percent by wind.
The migration of Oceanic biota was generally from west to east, with four major factors influencing their distribution and establishment. The first was the size and fertility of the islands on which they landed, with larger islands able to provide hospitality for a wider range of species. Second, the further east the islands, generally the less the species diversity, largely because of the distance that had to be crossed and because the eastern islands tended to be smaller, more scattered, and remote. This easterly decline in species diversity is well demonstrated by birds and coral fish. It is estimated that there were over 550 species of birds in New Guinea, 127 in the Solomon Islands, 54 in Fiji, and 17 in the Society Islands. From the west across the Pacific, the Bismarck Archipelago and the Solomon Islands have more than 90 families of shore fish (with many species within the families), Fyi has 50 families, and the Society Islands have 30.
Third, the latitude of the islands also influenced the biotic mix, as those islands in relatively cooler latitudes, notably New Zealand, were unsuited to supporting some of the tropical plants with which Pacific islands are generally associated.
Finally, a fourth major factor in species distribution, and indeed in the shaping of Pacific ecosystems, was wind. It takes little experience on Pacific islands to be aware that there are prevailing winds. To the north of the equator these are called north-easterlies, while to the south they are called south-easterlies. Further south, from about 30° south, the winds are generally from the west. As a result on nearly every island of significant size there is an ecological difference between its windward and leeward (away from the wind) sides. Apart from the wind action itself on plants and soils, wind has a major effect on rain distribution. The Big Island of Hawaii is often cited as a prime example; one can leave Kona on the leeward side in brilliant sunshine and drive across to the windward side where the city of Hilo is blanketed in mist and rain. [br] The word remnants in Paragraph 1 is closest in meaning to________.
选项
A、remainders
B、reminders
C、reproductions
D、resemblances
答案
A
解析
题干中remnants意为“遗迹;遗骸”,只有A项remainders(剩余物,残存物)与其意思相近,故正确答案为A项。B项“提醒”、C项“复制;繁衍”、D项“相似”均不符合题意,故都予以排除。
转载请注明原文地址:https://tihaiku.com/zcyy/3918970.html
相关试题推荐
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
Therearebothgreatsimilaritiesandconsiderablediversityintheecosyste
随机试题
WaystoHandleStressThismaycomeasasurprise,bu
Astotheverbtense,whichofthefollowingsentencesisdifferentfromtheoth
向商标局提交的各种证件、证明文件和证据材料是外文的,应当附送中文译文未附送的,视
稳压泵应有手、自动启停功能,启停信号、故障信号应能返馈至消防控制室。
钢筋混凝土受弯构件界限中和轴高度确定的依据是( )。A.平截面假设及纵向受拉钢
用实验法获取数据时,实验组和对照组的产生应当是()。A.随机的 B.配对的
甲公司向乙公司借款,甲公司董事长赵某用自己的一栋写字楼、夫妻共有的一幅古画做抵押
根据《堤防和疏浚工程施工合同范本》,造成工期延误,应由发包人承担责任的情况包括(
在进行分部分项工程项目清单的编制时,清单项目特征主要涉及()。A.项目的自身特
男,40岁。从三楼跌下,左6、7、8肋骨骨折,脾破裂、肠破裂。入院时精神紧张,T
最新回复
(
0
)