科学家报告气候变化对动物和生态系统的影响
2012-12-28 14:25阅读：
华盛顿――为寻求较为凉爽的气候，动植物在向山区高地迁移。一些鱼类的活动范围和数量缩小。其他的物种因无法适应气候变化而数量越来越少，可能走向灭绝。
这些发现来自一项范围广泛的研究――《气候变化对生物多样性、生态系统和生态系统服务功能的影响》（Impacts of Climate
Change on Biodiversity, Ecosystems and Ecosystem
Services）。研究由来自美国地质调查局（U.S. Geological
Survey）、学术界和侧重环保的非政府组织的科学家合作完成。
该科研小组集成了迄今有关候变化如何影响生态系统、这些生态系统为人类或其他生命形式提供的资源或实用功能、以及在这些生态系统内的生命多样性的了解。这份于12月18日发布的报告的结果将被纳入《国家气候评估报告》（National
Climate
Assessment）。根据法律规定，《国家气候评估报告》每四年向总统和国会提交一次。下次报告日期是2013年。
最新研究检视了来自美国全国各地的气候数据。这些数据显示，在降雨量、结冰天数、动物迁徙次数和物种繁殖习性方面发生了许多变化。亚利桑那州立大学坦佩校园（Arizona
State University in Tempe）科学家、该项研究的主要作者之一南希•格林（Nancy
Grimm）指出，这些变化正在“引发贯穿各生态系统的连锁效应。”
报告中的一个关键发现是，“越来越多的证据在显示可直接归因于气候变化的种群数量下降和局部灭绝。”
气候变化可能会打乱将各个生态系统物种交织在一起的生命网中的微妙平衡。温度升高可能使昆虫过早出现，从而使在季节性迁移中以新生幼虫为食物资源的候鸟无以食用。
与那些候鸟一样，我们人类也可能会发现，气候的变化会剥夺我们所依赖的资源。
科学家在一头阿拉斯加白鲸身上安装了一个跟踪装置。水体污染和过度狩猎使得这种生物的生存受到威胁。
全国野生动物保护协会（National Wildlife
Federation）气候学家、该项研究的另一位主笔阿曼达•施陶特（Amanda
Staudt）说：“气候变化对于生态系统的影响对民众和社区会产生重大影响。”“气候条件的改变正在影响生态系统的实用功能，诸如沿海生物栖息地在抑制风暴潮方面所发挥的作用、或是我们的森林提供木材和帮助过滤饮水的能力。”
例如，暴雨频发会把更多的污染物冲向下游，从而改变饮水的质量或带来更大的水源性疾病威胁。
这项研究报告旨在向美国的政策制定者通报国内正在发生的这些变化，然而这并不意味着这些环境变化仅发生在美国。
施陶特在回复一封电子邮件查询时这样写道：“报告中详细介绍的美国的那些类型的气候变化绝对在影响着世界各地的物种和生态系统。”她指出，参与撰写本报告的60多位美国科学家中，有些人曾在其研究中参考了国际上的研究成果。
她引用了国际自然保护联盟（International Union for Conservation of
Nature）的《濒危物种红色名录》（Red List of Threatened
Species），其中确定了4,000多个受到气温升高、干旱加重的威胁和其它因气候变化而变迁栖息地的物种。这项研究表明，在所研究的4,000个物种中，29％受到极端温度的影响，28％受到干旱影响。
这项美国的研究表明，气候变化正在改变着具有重要商业价值的海洋鱼类数量和活动范围。美国地质调查局科学家及报告主要作者米歇尔•施陶丁格（Michelle
Staudinger）说：“这些变化几乎肯定将会继续……从而导致一些本地渔场数目下降或消失，而另一些则可能增长并变得更有价值”――如果捕鱼业能够找到可行方式去适应变化的话。
《气候变化的影响》报告还明确肯定，气候变化是造成美国西部地区毁灭森林的野火和虫害的罪魁祸首。
报告指出，“积雪的巨大变化”、融化时间和土壤冻结频率，也正在给山区和相邻低地的土地和水域生态系统造成严重后果。
报告指出，找到适应方式对于保护多样化的物种和让保护环境者有效管理自然环境至关重要。报告作者之一、全国野生动物联合会负责气候适应研究的主任布鲁斯•斯坦因（Bruce
Stein）说：“自然保护界正在努力探索”如何实现这一目标。
Read more:
http://iipdigital.usembassy.gov/st/chinese/article/2012/12/20121226140387.html#ixzz2GKEOwsau
Scientists Report Climate Impact on Animals,
Ecosystems
Scientists put a tracking device on an Alaskan Beluga whale.
The creatures’ survival is threatened by water pollution and over
hunting.
Washington — Animals and plants are moving up mountainsides seeking
cooler temperatures. Some fish species have smaller ranges and less
abundance. Other species are diminishing in their numbers, unable
to adjust to climate change, with extinction being a possible
outcome.
These findings come from a wide-ranging study —
Impacts of
Climate Change on Biodiversity, Ecosystems and Ecosystem
Services — produced by a collaboration of scientists from the
U.S. Geological Survey (USGS), academia and environmentally
oriented nongovernmental organizations.
The scientific team synthesized current understanding of how
climate change is affecting ecosystems, those resources, or
services, that ecosystems supply to humans or other life forms, and
the diversity of life within those ecosystems. The report, released
December 18, is one resource that will be used in a National
Climate Assessment that is prepared by law for the president and
the U.S. Congress every four years and due in 2013.
Examining climatic data from all over the United States, the report
shows many shifts in rainfall, freeze dates, animal migration times
and species reproduction habits. These changes are “causing
cascading effects that extend through ecosystems,” said Nancy
Grimm, a scientist at Arizona State University in Tempe and a lead
author of the study.
One key finding of the report reveals “increasing evidence of
population declines and localized extinctions that can be directly
attributed to climate change.”
Climate changes may disrupt the delicate balance in the web of life
that binds the species of individual ecosystems. Warmer
temperatures might make insects emerge too early for migrating
birds that rely on the newborn bugs as a food source in their
seasonal travels.
Like those migrating birds, we humans could also find that climate
shifts deprive us of a resource on which we depend.
“The impact of climate change on ecosystems has important
implications for people and communities,” said Amanda Staudt, a
climate scientist at the National Wildlife Federation and another
lead author on the report. “Shifting climate conditions are
affecting ecosystem services, such as the role that coastal
habitats play in dampening storm surge or the ability of our
forests to provide timber and help filter our drinking
water.”
For example, frequent torrents of rain can push more pollutants
downstream, changing the quality of drinking water or posing a
greater threat of waterborne disease.
The purpose of the report is to inform U.S. policymakers on how
these changes are unfolding domestically, but that doesn’t mean
these environmental changes are unique to this country.
“The sorts of climate impacts that the report details for the
United States absolutely are affecting species and ecosystems
around the world,” Staudt wrote in response to an email inquiry.
She said that some of the more than 60 U.S. scientists involved in
this report consulted international studies in their
research.
She cites the International Union for Conservation of Nature's Red
List of Threatened Species, which has identified more than 4,000
species threatened by increased temperatures, harsher droughts and
other climate-related shifts in habitat. The research shows
temperature extremes affecting 29 percent of the 4,000 species
studied and droughts affecting 28 percent.
The U.S. research shows that climate change is shifting the
abundance and geographic range of commercially important ocean
fish. “These changes will almost certainly continue,” said Michelle
Staudinger, a USGS scientist and lead author, “resulting in some
local fisheries declining or disappearing while others may grow and
become more valuable,” if the fishing industry can find an
acceptable way to adapt to change.
Impacts of Climate Change also finds with high certainty
that climate change is a top cause of wildfire and tree insect
outbreaks that are killing forests in the western United
States.
“Profound changes in snowpack,” the timing of melting, and the
frequency of soil freezing are also causing serious consequences
for land and water ecosystems in mountains and adjoining lowlands,
the report finds.
Identifying ways to adapt is vital for the conservation of diverse
species and effective management of natural environments by human
environmental caretakers, the report says. “The conservation
community is grappling” with how to achieve that end, said
contributing author Bruce Stein, director of climate adaptation at
the National Wildlife Federation.
Read more:
http://iipdigital.usembassy.gov/st/english/article/2012/12/20121220140291.html#ixzz2GKETetg7
