根據聯合國今天發表的報告: 為了拯救地球免於飢餓、家庭取暖燃料匱乏、及氣候變遷所帶來最嚴重的影響，全球改採純素飲食(vegan)至關重要。

聯合國環境規劃署(UNPE)，永續資源管理跨國專家委員會發表報告：全球的人口預估將於2050年前成長為91億，而嗜食大量肉類奶類的西方飲食，是無法讓地球永續生存的飲食習慣。

這項報告表示："人口增加帶來越來越多的肉食消費，而農牧業對環境帶來的衝擊，預料將大幅地增加。不像石化燃料，農牧業不容易有替代方案：人都得吃東西。所以，如果要減輕農牧業對環境帶來的衝擊，唯一可行的辦法，只有靠全世界大規模的飲食改變，不吃動物產品。"

愛德格•赫衛區教授是這份報告的主要作者，他表示：生產動物性產品對環境造成的傷害，比生產建築材料，像砂子、水泥、塑膠跟金屬等都來的大。生產生質物還有穀物來餵養動物，跟燃燒石化燃料一樣危害劇烈。

聯合國報告的這項建議，也呼應了去年史登爵士所提出的忠告，史登爵士是前英國工黨的氣候變遷經濟顧問。他呼籲大家蔬食是對地球比較友善的飲食，聯合國跨政府氣候變遷小組的主席，帕卓理博士也大聲疾呼，要採行一週一素來抑制排碳。

委員會的專家分別將產品、資源、經濟活動、交通運輸等對環境造成的衝擊，排序其嚴重性，其中，農牧業跟燃燒石化燃料的危害一樣大，因為這兩項的消耗都伴隨著經濟成長而快速增加。

委員會的另一位主席，也是環境科學家的魏茨澤克說：越來越富裕的生活誘使人類吃更多的肉、乳製品。豢養的家畜消耗了世界大部分的穀物糧食、淡水資源、也用了大量的化學肥料、以及殺蟲劑。

經濟成長必須 "扣除" 能源以及農業部門，因為在國民所得加倍的同時，這兩種產業造成的環境衝擊也會上升約80%。

聯合國副秘書長，同時也是聯合國環境規劃署執行長的Achim Steiner說 "世界人口不斷增加、所得不斷提高、資源消耗越來越大、我們還得持續努力消弭貧窮。在這種世界局勢之下，各國政府的最大挑戰，就是得將經濟成長扣除環境破壞所帶來的成本。"

委員會也引用了包括千禧年生態系統評估 (Millennium Ecosystem Assessment) 在內的各種報告，列舉以下各項環境議題，供各國政府施政的優先重點。氣候變遷、棲地變遷、肥料裡過度添加氮磷元素、漁業濫捕、林業以及其他資源的過度開採、物種入侵、不安全的飲水及衛生問題、鉛暴露、城市空氣污染、職業場所污染。

報告指出，農業生產，特別是肉類及乳製品，消耗全世界70%的淡水資源、38％的土地資源、排放全球19％的溫室氣體。這項報告於禮拜六，在聯合國世界環境日同時發表。

去年聯合國糧農組織(FAO)預估，為了餵養不斷增加的世界人口，全球糧食生產必須在2050年之前提高70%。委員會還表示，農業生產效率的提升，完全不足以應付預期的人口成長。

任職於挪威科學與科技大學，主持工業生態研究所的Hertwich教授表示，大部分的人口成長將集中於開發中國家，他們不能再跟隨西方國家的發展模式，不斷增加消費。他還說：他們不應再跟隨我們的模式，而我們得發展新的科技，例如再生能源、或是新的灌溉方法。

A global shift towards a vegan diet is vital to save the world from hunger, fuel poverty and the worst impacts of climate change, a UN report said today.

As the global population surges towards a predicted 9.1 billion people by 2050, western tastes for diets rich in meat and dairy products are unsustainable, says the report from United Nations Environment Programme's (UNEP) international panel of sustainable resource management.

It says: "Impacts from agriculture are expected to increase substantially due to population growth increasing consumption of animal products. Unlike fossil fuels, it is difficult to look for alternatives: people have to eat. A substantial reduction of impacts would only be possible with a substantial worldwide diet change, away from animal products."

Professor Edgar Hertwich, the lead author of the report, said: "Animal products cause more damage than [producing] construction minerals such as sand or cement, plastics or metals. Biomass and crops for animals are as damaging as [burning] fossil fuels."

The recommendation follows advice last year that a vegetarian diet was better for the planet from Lord Nicholas Stern, former adviser to the Labour government on the economics of climate change. Dr Rajendra Pachauri, chair of the UN's Intergovernmental Panel on Climate Change (IPCC), has also urged people to observe one meat-free day a week to curb carbon emissions.

The panel of experts ranked products, resources, economic activities and transport according to their environmental impacts. Agriculture was on a par with fossil fuel consumption because both rise rapidly with increased economic growth, they said.

Ernst von Weizsaecker, an environmental scientist who co-chaired the panel, said: "Rising affluence is triggering a shift in diets towards meat and dairy products - livestock now consumes much of the world's crops and by inference a great deal of freshwater, fertilisers and pesticides."

Both energy and agriculture need to be "decoupled" from economic growth because environmental impacts rise roughly 80% with a doubling of income, the report found.
Achim Steiner, the UN under-secretary general and executive director of the UNEP, said: "Decoupling growth from environmental degradation is the number one challenge facing governments in a world of rising numbers of people, rising incomes, rising consumption demands and the persistent challenge of poverty alleviation."

The panel, which drew on numerous studies including the Millennium ecosystem assessment, cites the following pressures on the environment as priorities for governments around the world: climate change, habitat change, wasteful use of nitrogen and phosphorus in fertilisers, over-exploitation of fisheries, forests and other resources, invasive species, unsafe drinking water and sanitation, lead exposure, urban air pollution and occupational exposure to particulate matter.

Agriculture, particularly meat and dairy products, accounts for 70% of global freshwater consumption, 38% of the total land use and 19% of the world's greenhouse gas emissions, says the report, which has been launched to coincide with UN World Environment day on Saturday.

Last year the UN's Food and Agriculture Organisation said that food production would have to increase globally by 70% by 2050 to feed the world's surging population. The panel says that efficiency gains in agriculture will be overwhelmed by the expected population growth.

Prof Hertwich, who is also the director of the industrial ecology programme at the Norwegian University of Science and Technology, said that developing countries – where much of this population growth will take place – must not follow the western world's pattern of increasing consumption: "Developing countries should not follow our model. But it's up to us to develop the technologies in, say, renewable energy or irrigation methods."

原文引自：
http://www.guardian.co.uk/environment/2010/jun/02/un-report-meat-free-diet