2008年9月10日 星期三

6.2 what roles do species play in a community?

Niches can be occupied by native and nonnative species
different ecological roles or niches that native, nonnative, indicator, keystone, and foundation species.
most introduced species of crops and animals are beneficial to us.
1957 wild African bees(killer bees)

villain壞人,惡棍
allergic過敏的
flee逃,逃走

Indicator species are biological smoke alarms
provide early warnings of harmful environmental change
trout species in water
birds
butterflies
amphibians

trout
鱒魚
fragmentation
分裂;破碎
introduction引進,傳入
vulnerable
易受傷的
amphibian兩棲(類)的

Case study- why are amphibians vanishing?
amphibians- frogs, toads, and salamanders
indicator species
no single cause has been found to explain the amphibian declines
1.prolonged drought
2.pollution
3.viral, and fungal diseases
4.ultraviolet radiation
5.climate change(global warming)
6.overhunting
7.nonnative predators and competitors
如果多數兩棲類物種消失我們為何要關注?
1.environmental health is deterioration
2.improtant ecological roles (food chain)
3.genetic storehouse of pharmaceutical products

toad
蟾蜍,癩蛤蟆
salamander蠑螈
tadpole蝌蚪
block阻擋,妨礙,阻止
permeable
有滲透性的;可穿過的
readily
很快地,立即
draining排出(液體)
prolonged特別長的
breeding
生育,生殖;繁殖
viral病毒
fungal真菌的
embryo胚胎
parasite寄生蟲
deteriorating惡化
reptile
爬蟲類
pharmaceutical製藥的
secretion分泌物
painkiller鎮痛劑
antibiotic抗生素
larvae幼蟲;幼體

Keystone species play important roles in communities
eliminating a keystone species may dramatically alter the sturcture and function of community.
critcial ecological roles
bees, butterflies, hummingbirds蜂鳥, bat, dung beetle
top predator keystone species(wolf, leopard, lion, alligator)
ecological services

science focus-why should we protect sharks?
370 shark species
feeding at the tops of food webs, remove injured and sick animals form the ocean.
人類對鯊魚得誤解
valuable fins 魚刺可治百病
high levels of toxic mercury
livers, meat, hides, and jaws
cancer, immune system
especially vulnerable to overfishing
least protected animals on earth
that sharks may not need us, but we and other species need them

keystone species關鍵物種

wedge-shape楔形物
archway拱門
teeming
充滿的
dying垂死的
whale shark鯨鯊
basking shark姥鯊
megamouth shark巨口鯊
hack
劈,砍
ingredient
(烹調的)原料
fetch售得,賣得
dorsal背部的;背側的
mercury水銀,汞
liver肝臟
hide獸皮;皮革
deployed展開
immune免疫
aquarium水族館
outcry
強烈的抗議
dung糞;糞肥
churn攪拌
aerate使通氣

Foundation species also play important ecological roles
shaping communities by creating and enhancing the habits in ways that benefit other species.
elephants
bat and bird
beraver

forage草料
antelope羚羊
regenerate
重建;再生
beaver海狸,河狸
felling砍伐,砍倒
lodge巢穴


6.1 How does species diversity affect the sustainability of a community?

what is species diversity?
what is community? collection of populations of different species.
community characteristic
species and its interaction (feeding relationship)
species diversity- species richness and species evenness
niche structure-how many ecological nithes, how they resemble or different from one another, and how the species occupying different niches interact.
the most species-rich environments are
tropical rain forests,
coral reefs,
the ocean bottom zone, and
large tropical lakes.


Sustainability involves resisting or responding to changing environmental conditions
永續與穩定的三個面向
1.inertia or persistence 惰性
2.constancy恆定性
3.resilience回復
science focus
tropical rain forests vs. grasslands


species-rich communities tend to be productive and sustainable
theory and hypotheses
a species-rich community better able to recover or bounce back?
how much species diversity species richness is needed, still uncertain.
ecological roles play(6.2)

feeding relationship
攝食關係
species diversity
species richness種的數目或豐富度
species evenness種的均勻度
nitch structure
resemble像,類似
severe
嚴重的;劇烈的
three aspects of stablility or sustainablility in living system
inertia
慣性;慣量;惰性
constancy恆久不變
resilience恢復力
bounce
彈回
drought乾旱

chapter6-Community and population ecology

群落與種群生態學
core case study-
why should we care about the america alligator?
大沼澤國家公園地圖
1950年代開始大量捕殺為了肉exotic meat與皮supple belley skin, 1960s near extinction.
Alligator plays a number of roles in the ecosystems
niche- subtropical wetland communities
dig depressions or gator hole 可以儲水與食物給許多生物
nesting mounds
keep areas of open water, free of invading vegetation.
eat lagre numbers of gar, a predatory fish
keysotne species(幫助維持社群得結構、功能、永續)
1967列入enangered species list
世界自然保護聯盟瀕危物種紅色名錄
1977重新分類為threatened species
alligator farms


outlived比...活得長
exotic奇特的
supple柔軟的
belly腹部
out of hatred憎惡
Florida Everglades沼澤地
gator=alligator
nest巢;窩 mound土墩;土石堆
heron鷺,蒼鷺
egret白鷺
gar長嘴硬鱗魚
game fish 供垂釣的魚
bass鱸魚
bream太陽魚
shrub矮樹;灌木
keystone species關鍵物種
retriever一種獵犬
rogue兇猛的
filing a request
hide獸皮;皮革
highlight使顯著,使突出