秋千影/譯

The worlds most important crop is fuelling climate change and diabetes.全球最重要的糧食作物正在加重氣候變化及糖尿病病情。

The green revolution was one of the greatest feats of human ingenuity. By promoting higher-yielding varieties of wheat and， especially， rice， plantbreeders in India， Mexico and the Philippines helped India avoid a famine. From 1965 to 1995 Asias rice yields doubled and its poverty almost halved， even as its population soared.

綠色革命是人類智慧之偉績。通過推廣高產(chǎn)的小麥和水稻品種（后者尤為重要），印度、墨西哥和菲律賓的育種專家?guī)椭《缺苊饬思Z荒。1965年至1995年，盡管亞洲人口激增，但水稻產(chǎn)量翻倍，同時，貧困人口幾近減半。

Asias vast rice market is a legacy of that triumph. The starchy grain is the main source of sustenance for over half the worlds population. Asians produce over 90% of rice and get more than a quarter of their calories from it. And demand for the crop is projected to soar， on the back of population growth in Asia and Africa， another big rice consumer. By one estimate， the world will need to produce almost a third more rice by 2050. Yet that looks increasingly hard—and in some ways undesirable.

這一成就造就了亞洲龐大的大米市場，而這一淀粉糧食是世界上過半人口的生存之源。亞洲人生產(chǎn)超過90%的大米，也從大米獲取超過四分之一的熱量。非洲是大米的另一大消費(fèi)市場，由于亞非的人口增長，對大米的需求預(yù)計會猛增。有人預(yù)測，到2050年，世界需要增產(chǎn)三分之一的水稻，但做到這一點(diǎn)看似越來越難，從某些方面講，還會招致禍患。

Rice production is spluttering. Yields have increased by less than 1% a year over the past decade， much less than in the previous one. The greatest slowdowns were in South-East Asia， where Indonesia and the Philippines—together， home to 400m people—are already big importers. This has many explanations. Urbanisation and industrialisation have made labour and farmland scarcer. Excessive use of pesticides， fertiliser and irrigation have poisoned and depleted soils and groundwater. But the biggest reason may be global warming.

大米生產(chǎn)陷入窘境，過去的十年里，每年的產(chǎn)量增長不到1%，遠(yuǎn)遠(yuǎn)落后于上個十年。東南亞降幅最大，印度尼西亞和菲律賓兩國人口達(dá)4億，目前已需要大量進(jìn)口大米。這個現(xiàn)象原因很多：城市化和工業(yè)化導(dǎo)致勞動力減少、農(nóng)業(yè)用地稀缺；過度使用農(nóng)藥、化肥、灌溉導(dǎo)致土壤貧瘠和地下水枯竭；而最重要的原因或是全球變暖。

Rice is particularly susceptible to extreme conditions and is often grown in places where they are increasingly evident. Patchy monsoon rains and drought last year in India， the worlds biggest rice exporter， led to a reduced harvest and an export ban. Devastating floods in Pakistan， the fourth-biggest exporter， wiped out 15% of its rice harvest. Rising sea-levels are causing salt to seep into the Mekong Delta， Vietnams “rice bowl”.

水稻極易受極端天氣的影響，但其種植區(qū)的極端天氣卻越來越明顯。印度是世界最大的大米出口國，去年因為降雨稀少和干旱，導(dǎo)致產(chǎn)量減少，實行了出口限制。巴基斯坦是第四大大米出口國，但因洪水肆虐，水稻減產(chǎn)15%。在越南的“糧倉”湄公河三角洲，海水上漲，肥沃土壤遭鹽堿侵蝕。

It gets worse. Rice is not merely a casualty of climate change， but also a contributor to it. By starving soils of oxygen， paddy cultivation encourages methane-emitting bacteria. It is a bigger source of greenhouse gas than any foodstuff except beef. Its emissions footprint is similar to that of aviation. If you count the conversion of forestland for rice paddy—the fate of much of Madagascars rainforest—that footprint is even bigger.

更糟糕的是，水稻不僅受害于氣候變化，而且會加劇氣候變化。水稻種植會通過消耗土壤中的氧氣，滋生排放甲烷的微生物。在食物中，水稻產(chǎn)生的溫室效應(yīng)僅次于牛肉。其碳排放足跡類似于航空業(yè)的碳排放。如果把毀林造田考慮在內(nèi)，比如馬達(dá)加斯加大片雨林的命運(yùn)，其足跡更甚。

This amounts to an insidious feedback loop1 and， in all， a far more complicated set of problems than the food insecurity that spurred the green revolution. Indeed， eating too much rice turns out to be bad for people as well as the climate. White rice is more fattening than bread or maize， and is not especially nutritious. In South Asia rice-heavy diets have been linked to high rates of diabetes and persistent malnutrition.

由此導(dǎo)致的具有潛在危害的反作用最終會引發(fā)一系列問題，這些問題遠(yuǎn)比激發(fā)了綠色革命的糧食危機(jī)更為復(fù)雜。消費(fèi)太多大米最終的確會給人類和氣候造成危害。相較于面包和玉米，白米更容易使人發(fā)胖，而且不是很有營養(yǎng)。在南亞地區(qū)，以米為主的餐飲習(xí)慣與糖尿病高發(fā)和長期營養(yǎng)不良密切相關(guān)。

Policymakers need to increase rice yields， then， but more selectively than in the 1960s. In the places most suitable for rice cultivation， such as hot and sticky South-East Asia， faster adoption of new technologies， such as flood resistant and more nutritious seeds， could provide a big productivity boost. In tandem with improved practices， such as direct seeding of paddy， they could also shorten the growing cycle and reduce the amount of water required， mitigating environmental harm. Farmers have been slow to adopt such improvements， partly because of overgenerous subsidies that shield them from the rice crisis. A better approach would make state support contingent on best practice. By encouraging crop insurance—a good idea in itself—governments could also help reassure farmers as they switch from old ways to new.

因此，雖然決策者需要增加水稻產(chǎn)量，但與20世紀(jì)60年代相比，應(yīng)該更加有所選擇。像東南亞這種悶熱的最適合水稻種植的地區(qū)，應(yīng)該盡快采用新技術(shù)，比如推廣既具抗洪能力又更有營養(yǎng)的稻種，以確保增產(chǎn)。除了采用稻種直接種植等改良作法，同時可以縮短生長周期，從而減少水的需求量，減少對環(huán)境的危害。農(nóng)人一直懶于采用改良做法，部分原因在于過度慷慨的補(bǔ)貼讓他們對水稻危機(jī)缺乏切身感受。國家須改進(jìn)策略，基于種植方法來發(fā)放補(bǔ)貼。各國政府還可以通過提供作物保險——這本身是個好點(diǎn)子——讓農(nóng)人在更新技術(shù)時感到安心。

Governments need to nudge producers and consumers away from rice. India and Indonesia are promoting millet， which is more nutritious and uses a lot less water. Scrapping subsidies that favour rice over other crops would make such efforts more effective. India， for example， procures rice from farmers， often at above-market rates， then distributes it as food aid. It should make its interventions more crop-agnostic， by replacing subsidies and free rice with income support for farmers and cash transfers for the poor. That would encourage farmers to choose the best crop for their local conditions—much of Indias agricultural north-west would switch from rice to wheat overnight. Poor Indians would be free to choose a more balanced diet. Thereby， it would correct a market skewed towards en-vironmental damage and poor health.

各國政府應(yīng)該推動種植者和消費(fèi)者逐漸擺脫對稻米的依賴。印度和印度尼西亞正在推廣粟類作物，因為這類作物更有營養(yǎng)，且用水少得多。如能廢除水稻優(yōu)于其他作物的種植補(bǔ)貼，成效將更加顯著。比如，印度政府從稻民手中通常以高于市場的價格購得大米，然后以食物援助的形式發(fā)放下去。政府的干預(yù)措施應(yīng)該減少針對特定作物，停止發(fā)放補(bǔ)貼和免費(fèi)大米，轉(zhuǎn)而給農(nóng)人提供收入支持，給貧困人口提供現(xiàn)金支持，以此鼓勵農(nóng)人因地制宜地選擇作物——這樣的話，印度西北部農(nóng)業(yè)區(qū)的大部分地區(qū)會在一夜之間由水稻改種小麥。印度的窮人將自主選擇更均衡的飲食。如此一來，傾向于破壞環(huán)境、危害健康的市場將得以改觀。

Bringing about such change in Asia and beyond will be far harder than promoting new wonder seeds was. Farmers are almost everywhere a powerful consti-tuency. Yet policymakers should get used to blending complicated economic and technological fixes in this way. Increasingly， it is what fighting climate change will entail. Sorting out the mounting crisis in the worlds most important foodstuff would be a good place to begin.

在亞洲及其他地區(qū)，推行這樣的改良遠(yuǎn)遠(yuǎn)難于推廣神奇稻種。在任何地區(qū)，農(nóng)民總是最強(qiáng)有力的選民群體。但是，決策者應(yīng)該習(xí)慣于用這種方式將復(fù)雜的經(jīng)濟(jì)與技術(shù)改進(jìn)融為一體。這越來越成為對抗氣候變化的必由之路。解決全世界最重要的糧食領(lǐng)域日益嚴(yán)重的危機(jī)將是首要抓手。