白蚁堪称非洲草原生态系统之星
文章来源:未知 文章作者:meng 发布时间:2010-05-26 06:07 字体: [ ]  进入论坛
(单词翻译:双击或拖选)

The majestic1 animals most closely associated with the African savanna2(热带草原) -- fierce(凶猛的,暴躁的) lions, massive elephants, towering giraffes(长颈鹿) -- may be relatively3 minor4 players when it comes to shaping the ecosystem5. The real king of the savanna appears to be the termite6(白蚁) , say ecologists who've found that these humble7 creatures contribute mightily8 to grassland9 productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds11(堆) greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity.

The finding, published this week in the journal PLoS Biology, affirms a counterintuitive(违反直觉的) approach to population ecology: Often it's the small things that matter most.

"It's not always the charismatic(神赐能力的,超凡魅力的) predators12 -- animals like lions and leopards13 -- that exert(运用,发挥) the greatest control on populations," says Robert M. Pringle, a research fellow at Harvard University. "As E.O. Wilson likes to point out, in many respects it's the little things that run the world. In the case of the savanna, it appears these termites14 have tremendous influence and are central to the functioning of this ecosystem."

Prior research on the Kenya dwarf15(侏儒) gecko(壁虎) initially16 drew Pringle's attention to the peculiar17 role of grassy18 termite mounds, which in this part of Kenya are some 10 meters in diameter and spaced some 60 to 100 meters apart. Each mound10 teems19 with millions of termites, who build the mounds over the course of centuries.

After observing unexpectedly high numbers of lizards20 in the vicinity of(在……附近) mounds, Pringle and his colleagues began to quantify ecological21 productivity relative to mound density22. They found that each mound supported dense23 aggregations24(雌虫聚集) of flora25 and fauna26(动植物群) : Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably27(相当地,明显地) with greater distance.

What was observed on the ground was even clearer in satellite imagery. Each mound -- relatively inconspicuous(不显眼的) on the Kenyan grassland -- stood at the center of a burst of floral productivity. More importantly, these bursts were highly organized in relation to one another, evenly dispersed28 as if squares on a checkerboard(棋盘) . The result, says Pringle, is an optimized29 network of plant and animal output closely tied to the ordered distribution of termite mounds.

"In essence, the highly regular spatial30 pattern(空间格局) of fertile mounds generated by termites actually increases overall levels of ecosystem production. And it does so in such a profound way," says Todd M. Palmer, assistant professor of biology at the University of Florida and an affiliate31(隶属的机构) of the Mpala Research Centre in Nanyuki, Kenya. "Seen from above, the grid-work of termite mounds in the savanna is not just a pretty picture. The over-dispersion, or regular distribution of these termite mounds, plays an important role in elevating the services this ecosystem provides."

The mechanism32 through which termite activity is transformed into far-reaching effects on the ecosystem is a complex one. Pringle and Palmer suspect termites import coarse particles into the otherwise fine soil in the vicinity of their mounds. These coarser particles promote water infiltration33(渗透) of the soil, even as they discourage disruptive(破坏的,分裂性的) shrinking and swelling34 of topsoil in response to precipitation(坠落,沉淀) or drought.

The mounds also show elevated levels of nutrients35 such as phosphorus(磷) and nitrogen. All this beneficial soil alteration36 appears to directly and indirectly37 mold ecosystem services far beyond the immediate38 vicinity of the mound.

While further studies will explore the mechanism through which these spatial patterns of termite mounds emerge, Pringle and Palmer suggest that the present work has implications beyond the basic questions of ecology.

"Termites are typically viewed as pests, and as threats to agricultural and livestock39 production," Pringle says. "But productivity -- of both wild and human-dominated landscapes -- may be more intricately(杂乱地) tied to the pattern-generating organisms of the larger natural landscape than is commonly understood."

The findings also have important implications for conservation, Palmer says.

"As we think restoring degraded(退化的,堕落的) ecosystems40, as we think about restoring coral reefs, or restoring plant communities, this over-dispersed pattern is teaching us something," he says. "It's saying we might want to think about doing our coral restoration or plant restoration in a way that takes advantage of this ecosystem productivity enhancing phenomenon."



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1 majestic GAZxK     
adj.雄伟的,壮丽的,庄严的,威严的,崇高的
参考例句:
  • In the distance rose the majestic Alps.远处耸立着雄伟的阿尔卑斯山。
  • He looks majestic in uniform.他穿上军装显得很威风。
2 savanna bYbxZ     
n.大草原
参考例句:
  • The savanna is also the home of meat-eaters--the lion,leopard,and hyena who feed on the grasseaters.大草原也是食肉动物的家乡--狮子、豹、鬣狗--它们都是以草食动物维持生命的。
  • They sped upon velvet wheels across an exhilarant savanna.他们的马车轻捷地穿过一片令人赏心悦目的大草原。
3 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
4 minor e7fzR     
adj.较小(少)的,较次要的;n.辅修学科;vi.辅修
参考例句:
  • The young actor was given a minor part in the new play.年轻的男演员在这出新戏里被分派担任一个小角色。
  • I gave him a minor share of my wealth.我把小部分财产给了他。
5 ecosystem Wq4xz     
n.生态系统
参考例句:
  • This destroyed the ecosystem of the island.这样破坏了岛上的生态系统。
  • We all have an interest in maintaining the integrity of the ecosystem.维持生态系统的完整是我们共同的利益。
6 termite npTwE     
n.白蚁
参考例句:
  • The termite control was also probed into further in this text.本文还进一步探讨了白蚁的防治方法。
  • Termite often destroys wood.白蚁经常破坏树木。
7 humble ddjzU     
adj.谦卑的,恭顺的;地位低下的;v.降低,贬低
参考例句:
  • In my humble opinion,he will win the election.依我拙见,他将在选举中获胜。
  • Defeat and failure make people humble.挫折与失败会使人谦卑。
8 mightily ZoXzT6     
ad.强烈地;非常地
参考例句:
  • He hit the peg mightily on the top with a mallet. 他用木槌猛敲木栓顶。
  • This seemed mightily to relieve him. 干完这件事后,他似乎轻松了许多。
9 grassland 0fCxG     
n.牧场,草地,草原
参考例句:
  • There is a reach of grassland in the distance.远处是连绵一片的草原。
  • The snowstorm swept the vast expanse of grassland.暴风雪袭击了辽阔的草原。
10 mound unCzhy     
n.土墩,堤,小山;v.筑堤,用土堆防卫
参考例句:
  • The explorers climbed a mound to survey the land around them.勘探者爬上土丘去勘测周围的土地。
  • The mound can be used as our screen.这个土丘可做我们的掩蔽物。
11 mounds dd943890a7780b264a2a6c1fa8d084a3     
土堆,土丘( mound的名词复数 ); 一大堆
参考例句:
  • We had mounds of tasteless rice. 我们有成堆成堆的淡而无味的米饭。
  • Ah! and there's the cemetery' - cemetery, he must have meant. 'You see the mounds? 啊,这就是同墓,”——我想他要说的一定是公墓,“看到那些土墩了吗?
12 predators 48b965855934a5395e409c1112d94f63     
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
参考例句:
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
13 leopards 5b82300b95cf3e47ad28dae49f1824d1     
n.豹( leopard的名词复数 );本性难移
参考例句:
  • Lions, tigers and leopards are all cats. 狮、虎和豹都是猫科动物。 来自《简明英汉词典》
  • For example, airlines never ship leopards and canaries on the same flight. 例如,飞机上从来不会同时运送豹和金丝雀。 来自英语晨读30分(初三)
14 termites 8ee357110f82dc8b267190e430924662     
n.白蚁( termite的名词复数 )
参考例句:
  • Termites are principally tropical in distribution. 白蚁主要分布在热带地区。 来自辞典例句
  • This spray will exterminate the termites. 这种喷剂能消灭白蚁。 来自辞典例句
15 dwarf EkjzH     
n.矮子,侏儒,矮小的动植物;vt.使…矮小
参考例句:
  • The dwarf's long arms were not proportional to his height.那侏儒的长臂与他的身高不成比例。
  • The dwarf shrugged his shoulders and shook his head. 矮子耸耸肩膀,摇摇头。
16 initially 273xZ     
adv.最初,开始
参考例句:
  • The ban was initially opposed by the US.这一禁令首先遭到美国的反对。
  • Feathers initially developed from insect scales.羽毛最初由昆虫的翅瓣演化而来。
17 peculiar cinyo     
adj.古怪的,异常的;特殊的,特有的
参考例句:
  • He walks in a peculiar fashion.他走路的样子很奇特。
  • He looked at me with a very peculiar expression.他用一种很奇怪的表情看着我。
18 grassy DfBxH     
adj.盖满草的;长满草的
参考例句:
  • They sat and had their lunch on a grassy hillside.他们坐在长满草的山坡上吃午饭。
  • Cattle move freely across the grassy plain.牛群自由自在地走过草原。
19 teems 61b8eaf2974f281b7d0512335d2dae9b     
v.充满( teem的第三人称单数 );到处都是;(指水、雨等)暴降;倾注
参考例句:
  • The swamp teems with mosquitoes. 这片沼泽地蚊子多极了。 来自《现代英汉综合大词典》
  • That book teems with blunders. 那本书错误不少。 来自辞典例句
20 lizards 9e3fa64f20794483b9c33d06297dcbfb     
n.蜥蜴( lizard的名词复数 )
参考例句:
  • Nothing lives in Pompeii except crickets and beetles and lizards. 在庞培城里除了蟋蟀、甲壳虫和蜥蜴外,没有别的生物。 来自辞典例句
  • Can lizards reproduce their tails? 蜥蜴的尾巴断了以后能再生吗? 来自辞典例句
21 ecological IrRxX     
adj.生态的,生态学的
参考例句:
  • The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
  • Each animal has its ecological niche.每种动物都有自己的生态位.
22 density rOdzZ     
n.密集,密度,浓度
参考例句:
  • The population density of that country is 685 per square mile.那个国家的人口密度为每平方英里685人。
  • The region has a very high population density.该地区的人口密度很高。
23 dense aONzX     
a.密集的,稠密的,浓密的;密度大的
参考例句:
  • The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
  • The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。
24 aggregations 4c4f91ef635e1dd162c5cdd100d293aa     
n.聚集( aggregation的名词复数 );集成;集结;聚集体
参考例句:
  • A pattern of overlapping aggregations is usually found. 通常可发现一种叠聚集现象。 来自辞典例句
  • The atoms of the different chemical elements are different aggregations of atoms of the same kind. 不同化学元素的原子是同类原子的不同聚合物。 来自辞典例句
25 flora 4j7x1     
n.(某一地区的)植物群
参考例句:
  • The subtropical island has a remarkably rich native flora.这个亚热带岛屿有相当丰富的乡土植物种类。
  • All flora need water and light.一切草木都需要水和阳光。
26 fauna 9kExx     
n.(一个地区或时代的)所有动物,动物区系
参考例句:
  • This National Park is an area with unique fauna and flora.该国家公园区域内具有独特的动物种群和植物种群。
  • Fauna is a biological notion means all the animal life in a particular region or period. 动物群是一个生物学的概念,指的是一个特定时期或者地区的所有动物。
27 appreciably hNKyx     
adv.相当大地
参考例句:
  • The index adds appreciably to the usefulness of the book. 索引明显地增加了这本书的实用价值。
  • Otherwise the daily mean is perturbed appreciably by the lunar constituents. 否则,日平均值就会明显地受到太阳分潮的干扰。
28 dispersed b24c637ca8e58669bce3496236c839fa     
adj. 被驱散的, 被分散的, 散布的
参考例句:
  • The clouds dispersed themselves. 云散了。
  • After school the children dispersed to their homes. 放学后,孩子们四散回家了。
29 optimized 81c61ac8ff2adb570ce4c7e7dfed59bd     
adj.最佳化的,(使)最优化的v.使最优化,使尽可能有效( optimize的过去式和过去分词 )
参考例句:
  • We are often asked whether consumer Web sites should be optimized for beginners or intermediates. 我们常常被问到这样的问题:消费类网站究竟应该为新手而优化,还是应该为中间用户而优化? 来自About Face 3交互设计精髓
  • GOOGLE Advertising optimized sequence, greatly increasing the advertising effect. 优化了GOOGLE广告位排列顺序,大大增加了广告效果。 来自互联网
30 spatial gvcww     
adj.空间的,占据空间的
参考例句:
  • This part of brain judges the spatial relationship between objects.大脑的这部分判断物体间的空间关系。
  • They said that time is the feeling of spatial displacement.他们说时间是空间位移的感觉。
31 affiliate TVBzj     
vt.使隶(附)属于;n.附属机构,分公司
参考例句:
  • Our New York company has an affiliate in Los Angeles.我们的纽约公司在洛杉矶有一个下属企业。
  • What is the difference between affiliate and regular membership?固定会员和附属会员之间的区别是什么?
32 mechanism zCWxr     
n.机械装置;机构,结构
参考例句:
  • The bones and muscles are parts of the mechanism of the body.骨骼和肌肉是人体的组成部件。
  • The mechanism of the machine is very complicated.这台机器的结构是非常复杂的。
33 infiltration eb5za     
n.渗透;下渗;渗滤;入渗
参考例句:
  • The police tried to prevent infiltration by drug traffickers. 警方尽力阻止毒品走私分子的潜入。 来自《简明英汉词典》
  • A loss in volume will occur if infiltration takes place. 如果发生了渗润作用,水量就会减少。 来自辞典例句
34 swelling OUzzd     
n.肿胀
参考例句:
  • Use ice to reduce the swelling. 用冰敷消肿。
  • There is a marked swelling of the lymph nodes. 淋巴结处有明显的肿块。
35 nutrients 6a1e1ed248a3ac49744c39cc962fb607     
n.(食品或化学品)营养物,营养品( nutrient的名词复数 )
参考例句:
  • a lack of essential nutrients 基本营养的缺乏
  • Nutrients are absorbed into the bloodstream. 营养素被吸收进血液。 来自《简明英汉词典》
36 alteration rxPzO     
n.变更,改变;蚀变
参考例句:
  • The shirt needs alteration.这件衬衣需要改一改。
  • He easily perceived there was an alteration in my countenance.他立刻看出我的脸色和往常有些不同。
37 indirectly a8UxR     
adv.间接地,不直接了当地
参考例句:
  • I heard the news indirectly.这消息我是间接听来的。
  • They were approached indirectly through an intermediary.通过一位中间人,他们进行了间接接触。
38 immediate aapxh     
adj.立即的;直接的,最接近的;紧靠的
参考例句:
  • His immediate neighbours felt it their duty to call.他的近邻认为他们有责任去拜访。
  • We declared ourselves for the immediate convocation of the meeting.我们主张立即召开这个会议。
39 livestock c0Wx1     
n.家畜,牲畜
参考例句:
  • Both men and livestock are flourishing.人畜两旺。
  • The heavy rains and flooding killed scores of livestock.暴雨和大水淹死了许多牲口。
40 ecosystems 94cb0e40a815bea1157ac8aab9a5380d     
n.生态系统( ecosystem的名词复数 )
参考例句:
  • There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
  • Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样,从雨林到半荒漠等不一而足。 来自辞典例句
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