时间:2018-12-16 作者:英语课 分类:2018年VOA慢速英语(七)月


英语课

Africa's Baobab Trees Are Dying


Baobab trees are not only iconic images of dry, hot areas of Africa. Baobabs are important because they supply water and food for people and animals. They are sometimes called “the tree of life.”


Yet, say researchers, some baobabs are mysteriously dying.


Nine of the 13 oldest trees, aged 1 between 1,000 and 2,500 years, have died in the early part of this century. Researchers reported the finding in the scientific journal Nature Plants.


The sudden collapse 2 is “an event of unprecedented 3 magnitude 4,” the researchers wrote. They believe that never before have so many old trees died in such a short period. These baobabs were found in the southern African countries of Botswana, Namibia, South Africa, Zambia and Zimbabwe.


Researchers do not know for sure why the trees died. But they note that temperatures have risen and rainfall decreased in recent years.


Stephan Woodborne helped to prepare a report on the study. Woodborne is with South Africa’s National Research Foundation. He says the researchers do not think that baobabs across the continent are dying out. Instead, they believe the climate of southern Africa is changing.


Researchers have observed few young trees in the places where the old trees are dying. As a result, Woodborne says, baobab trees will probably stop growing in some places, and may start growing in others. He calls the move a reaction to “climate forcing.”


Historically, baobabs are often found in areas where elephants, rhinoceros 5 and other wildlife live. Elephants help the trees spread when they eat baobab fruit. The seeds often grow in the nutritious 6 elephant dung.


Baobabs take in large amounts of water during the rainy season and store it in their trunks and tree branches. The water gives the trees their wide shape. Large trees can store as much as 140,000 liters. Thirsty elephants tear off the trees’ bark and wood to get to the water inside.


Baobabs are also important to people. Researcher Stephan Woodborne notes that communities have been using the trees for a long time. His group has found many archaeological remains 7 underneath 8 ancient trees from societies that lived hundreds of years ago.


Even today, people gather around the trees for religious events and to communicate with family and friends who have died. People also use the baobab fruit to make drinks and mix with milk to create a kind of yogurt. In addition, the trees offer protection from the sun on hot summer days.


Anna Munzhelele lives near the Limpopo River in South Africa. She said eating baobab fruit makes people strong. “It’s like a type of medicine, we get energy from it,” she said.


I’m Kelly Jean Kelly.


Words in This Story


iconic - adj. widely recognized


unprecedented - adj. not done or experienced before


magnitude - n. the size, extent, or importance of something


dung - n. solid waste from an animal


thirsty - adj. needing water


bark - n. the outer covering of a tree


wood - n. the hard substance that makes up the stems and branches of trees and shrubs



1 aged
adj.年老的,陈年的
  • He had put on weight and aged a little.他胖了,也老点了。
  • He is aged,but his memory is still good.他已年老,然而记忆力还好。
2 collapse
vi.累倒;昏倒;倒塌;塌陷
  • The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
  • The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做了一次彻底的调查分析。
3 unprecedented
adj.无前例的,新奇的
  • The air crash caused an unprecedented number of deaths.这次空难的死亡人数是空前的。
  • A flood of this sort is really unprecedented.这样大的洪水真是十年九不遇。
4 magnitude
n.大小;重大;星等
  • I want to know the magnitude of this equipment.我想知道这个设备的大小。
  • I hadn't realized the magnitude of the problem.我没有认识到这个问题的重要性。
5 rhinoceros
n.犀牛
  • The rhinoceros has one horn on its nose.犀牛鼻子上有一个角。
  • The body of the rhinoceros likes a cattle and the head likes a triangle.犀牛的形体像牛,头呈三角形。
6 nutritious
adj.有营养的,营养价值高的
  • Fresh vegetables are very nutritious.新鲜蔬菜富于营养。
  • Hummingbirds have discovered that nectar and pollen are very nutritious.蜂鸟发现花蜜和花粉是很有营养的。
7 remains
n.剩余物,残留物;遗体,遗迹
  • He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
  • The remains of the meal were fed to the dog.残羹剩饭喂狗了。
8 underneath
adj.在...下面,在...底下;adv.在下面
  • Working underneath the car is always a messy job.在汽车底下工作是件脏活。
  • She wore a coat with a dress underneath.她穿着一件大衣,里面套着一条连衣裙。
学英语单词
-free
Abiturients
absolute indirect addressing
aerial for television transmitter
alternating tension and compression
aneurysmodesis
array for real-time geostrophic oceanography (argo)
avania
Bellergal-S
benzo light blue fr
breast the tape
bulk bread
Cerasus yunnanensis
chimney pot
chuffers
color meter
combined immunodeficiency syndrome
concentrating pan
cow bitten
cranial sympathetic system
cumulative timing
despiseress
directly ionizing radiation
disease natural history
dome cells
Doppler beam sharpening
downfolds
Drachkava
emergent evolution
ends-of
essence of a contract
Evil one,the
exercitives
failure processing
food fishes
footplates
forceless deep pulse
glueings
glutamatergic pathway
gompper
grandpaternity
hard over
helispheric
helpdesk
Hertwig epithelial root sheath
Honda alloy
hutchens
Hydroglimmer
in contact
jarvital
john davyss
kamauu
Kasagi-yama
Lindblad resonance
liquidnesses
logocentricity
macrame
master clutch brake
Matthew Walker knot
medium-frequency oscillator
membranogenesis
metallocenes
myxosporan
osteoblastogenesis
ottaway
overlapped memorys
parthenocissus himalayana (royle) planch.
plate streak
pulse repetition (or recurrence) period
pyre (egypt)
quiescent chamber
rattle-head
reciprocity curve
recommodifies
redruthite
regular solid
reinfections
repetitively
riras
roughing tooth profile
Sarvabad
sclero-ridencleisis
semi-range
sorting inspection
spinulous
stathis
sticta wrightii
stone mulching
subspecialist
temporary removal
thermal receiver
thermochromic display
ticalopride
turkey in the straw
ulex europaeuss
volume quotation system
wave power generating ship
wet willies
white blood cell
worsteds
ziwuliuzhu