大自然的“過濾器”正在消亡，沒有人知道原因

大自然的“過濾器”正在消亡，沒有人知道原因

The shells lie open at the bottom of the river, shimmering in the refracted sunlight. Their insides, pearl white and picked clean of flesh, flicker against the dark riverbed like a beacon, alerting the world above to a problem below.

貝殼在河底張開，在折射的陽光下閃閃發(fā)光。它們的身體，潔白如珠，剔得干干凈凈，像燈塔一樣在黑暗的河床上閃爍，提醒著上面的世界注意下面的問題。

"That's what we look for in die-offs," says biologist Jordan Richard, standing knee-deep in the slow-flowing waters of the Clinch River in southwest Virginia. He points at a faint shape submerged about 10 feet upstream. "I can tell from here that's a shell, it's dead and it died recently. The algae development is really light."

生物學(xué)家喬丹·理查德站在弗吉尼亞州西南部克林奇河齊膝深的緩流水域中說:“這就是我們在動物死亡中尋找的東西。”他指著上游大約10英尺處一個模糊的物體。“我從這里就能看出那是只雉雞殼，它死了，最近才死的。藻類的生長真的很緩慢。”

In recent years, though, biologists and fishermen noticed something was wrong. On sections of the Clinch and other waterways in the Pacific Northwest and Midwest, dead mussels were turning up on shores and could be seen glinting from the river bottom.

然而，近年來，生物學(xué)家和漁民發(fā)現(xiàn)了一些問題。在太平洋西北部和中西部的克林奇河和其他水道的一些河段，可以看到死貽貝在河底閃閃發(fā)光。

On the Clinch River alone, hundreds of thousands are believed to have perished, a mass mortality event that has baffled scientists and alarmed ecologists.

據(jù)信，僅在克林奇河就有數(shù)十萬貝殼死亡。這一大規(guī)模死亡事件令科學(xué)家困惑，也令生態(tài)學(xué)家感到恐慌。

Freshwater mussels, like pollinators and trees, are critical to their larger ecosystems and the world around them. They create habitat for other species, like freshwater coral reefs, and help maintain the structure and rigidity of the waterways they call home. They scoop up algae and nutrients, processing and concentrating them for others to eat.

淡水貽貝，像傳粉者和樹木一樣，對它們更大的生態(tài)系統(tǒng)和周圍的世界至關(guān)重要。它們?yōu)榈汉鹘傅绕渌锓N創(chuàng)造了棲息地，并幫助維持它們稱之為家的水道的結(jié)構(gòu)和硬度。它們把海藻和營養(yǎng)物質(zhì)撈起來，加工并濃縮起來供其他動物食用。

But perhaps most importantly, these soft-bodied invertebrates improve the water quality around them (check out this video.) They filter out sediment and agricultural runoff, limiting the size and impacts of dead zones. They reduce fecal bacteria from water, lowering the risk of E. coli.

但也許最重要的是，這些軟體無脊椎動物改善了它們周圍的水質(zhì)。它們過濾掉了沉積物和農(nóng)業(yè)排水，限制了死亡區(qū)的面積和影響。它們減少了水中的糞便細(xì)菌，降低了大腸桿菌的風(fēng)險。

They sequester carbon, phosphorous and heavy metals. There's even evidence they can remove man-made contaminantsfrom water such as pharmaceuticals, flame retardants and personal care products.

它們能隔絕碳、磷和重金屬。甚至有證據(jù)表明，它們可以清除水中的人造污染物，如藥品、阻燃劑和個人護(hù)理產(chǎn)品。

A single freshwater mussel can filter more than 15 gallons of water in a day.

一個淡水貽貝一天可以過濾超過15加侖的水。

They're like nature's "filter," says Emilie Blevins, a conservation biologist with the Xerces Society for Invertebrate Conservation, an Oregon-based nonprofit that's monitoring and studying the recent die-offs.

它們就像大自然的“過濾器”，埃米利·布萊文斯是Xerces無脊椎動物保護(hù)協(xié)會的一名保護(hù)生物學(xué)家，Xerces協(xié)會位于俄勒岡州，是一家監(jiān)測和研究最近物種滅絕的非盈利組織。

"The loss is really huge and it's happening really quickly," Blevins says. "It's a major concern for the future and for the future of our fresh water."

“損失是巨大的，而且發(fā)生得非常快，”布萊文斯說。“這是對未來和我們的淡水的未來的主要擔(dān)憂。”

Freshwater mussels are one of most imperiled species on the planet. Nearly three-quarters of North America's roughly 300 native mussel species are endangered, at risk, or of concern. Dozens are already extinct. Humans are the primary cause.

淡水貽貝是地球上最瀕危的物種之一。北美約300種本地貽貝中，有近四分之三瀕臨滅絕或受到威脅。數(shù)十種已經(jīng)滅絕。人類是主要原因。

For decades, freshwater mussels were overharvested for their shells. Before the era of plastic, they were collected and cultivated by the millions to satisfy a commercial demand.

幾十年來，淡水貽貝因其外殼而被過度捕撈。在塑料時代之前，它們被數(shù)以百萬計的人收集和種植，以滿足商業(yè)需求。

A recent report by the United Nations found that human practices have put roughly 1 million species at risk of extinction, many within decades.

聯(lián)合國最近的一份報告發(fā)現(xiàn)，人類的行為已經(jīng)讓大約100萬個物種面臨滅絕的危險，其中許多物種會在幾十年內(nèi)滅絕。

"The essential, interconnected web of life on Earth is getting smaller and increasingly frayed," wrote Josef Settele, a German biologist and co-chair of the report. "This loss is a direct result of human activity and constitutes a direct threat to human well-being in all regions of the world."

“地球上必不可少的、相互聯(lián)系的生命網(wǎng)絡(luò)正在變得越來越小，而且越來越脆弱，”該報告的聯(lián)合主席、德國生物學(xué)家約瑟夫·塞特爾寫道。“這種損失是人類活動的直接結(jié)果，并對世界所有區(qū)域的人類福祉構(gòu)成直接威脅。”

Nature is so complex. Biology is so complex. We do not understand how important some things are until they're gone.

大自然是如此復(fù)雜。生物學(xué)是如此復(fù)雜。有些東西只有消失了，我們才知道它有多重要。