又到一年飛絮季 北京繪“楊柳地圖” 力爭到2020年改善

又到了每年的飛絮季節，出趟門，像是在大雪天裏行走。尤其是對過敏性鼻炎患者來說，在漫天飛絮中一邊擦鼻涕，一邊打噴嚏，畫面簡直不要太美。

爲了應對這一狀況，北京市已經繪製了在春天造成大範圍飛絮的楊柳樹雌株分佈地圖，力爭到2020年使楊柳飛絮明顯改善。

Beijing has mapped its female poplar and willow trees to try to contain catkins that descend on the city each spring.

北京已經繪製了楊柳樹雌株的分佈地圖，試圖控制在每年春天都出現的柳樹和楊樹飛絮。

catkin['kætkɪn]：n. [植]柔荑花序（如柳絮等）

The Chinese capital has been blanketed by catkins each spring for decades.

幾十年來，北京每年春天都深受楊柳飛絮的困擾。

很多網友紛紛在網上吐槽，春天有一種痛，叫會呼吸的痛……

The trees were planted in the 1960s and 1970s as a cheap, easy-to-maintain and quick-growing way to make Beijing greener.

這些樹木是在上世紀六七十年代種植的，因爲這種綠化樹木對北京來說價格便宜、易於維護而又生長快速。

Female trees look very similar to the males. The capital’s parks authority began a survey in 2017 to find out where female willows and poplars were planted so it could neutralize the catkins and go some way to sparing citizens weeks of sneezing and watery eyes as pollen spread, Beijing Youth Daily reported on Monday.

雌株從外觀看起來與雄株非常相似。據《北京青年報》本週一報道，北京市公園管理部門2017年開始進行調查，以確定楊柳樹雌株都分佈在哪裏，這樣就可以控制飛絮，從而在一定程度上讓市民免受數週花粉傳播導致的打噴嚏和流眼淚等症狀困擾。

neutralize['nju:trəlaiz]：vt.中和；使無效

Aerial photography was used, with urban areas inside the Fifth Ring Road – where most of the city’s population lives – divided into 2,866 grids, each of 250,000 square meters, Qin Yongsheng, an official with the Beijing Gardening and Greening Bureau, said.

北京市林業工作總站副站長秦永勝說，調查人員採用航拍技術，把五環內城區劃分成2866張航片網格圖。每個網格的範圍是25萬平方米。北京市絕大多數市民都生活在五環內。

Three hundred students from Beijing Forestry University trained to identify the female varieties plotted the trees’ locations by species and growth, and marked them for follow-up action if required.

北京林業大學的300名經過培訓的學生擔任了此次的調查人員，他們按照種類和生長速度確定楊柳樹雌株的分佈，並標記位置，爲後續行動做準備。

The survey found there were 284,000 female willows and poplars inside the Fifth Ring Road, with nearly 38 percent in the Chaoyang district. In some areas, there were about 10,000 such trees within one grid, with the highest densities found in the southwest of the city, between the Fourth and Fifth ring roads.

調查發現，北京五環內共有楊柳樹雌株28.4萬株，其中近38%在朝陽區。在一些地區，一個網格內大約有1萬株雌株，密度最高的是在北京西南四環和五環之間。

Up to 60 percent of the poplar trees are growing well, and that means they produce catkins.

其中多達60%的楊樹生長態勢良好，也就意味着它們能產生很多楊絮。

“The higher the density, the more serious the catkin phenomenon,” Qin was quoted as saying.

“密度越高，飛絮現象就越嚴重，”秦永勝說。

The parks authority tried using inhibitors to curb budding last year but it did not work well, it said. Other measures have been introduced this year.

公園管理部門曾在去年嘗試使用抑制劑阻止雌株發芽，但沒有奏效。工作人員在今年還採取了其他措施。

inhibitor [ɪn'hɪbɪtə]：n. [助劑]抑制劑，抗化劑

圖片來源：新浪微博 “We have trimmed some branches. We will also use high-pressure water guns to take down the seeds and sweep them away,” Wang Xiaoping, another bureau official, was quoted as saying. “We aim to significantly improve the catkin situation by 2020.”

據報道，北京市園林綠化局副巡視員王小平說：“園林工人已經對楊樹和柳樹的枝條進行修剪，還用高壓噴霧車對着樹冠沖洗，沖走楊柳絮，力爭到2020年使楊柳飛絮明顯改善。”

除此以外，還可以對柳樹採用高位嫁接（top grafting），將雌株變成雄株，以變性來達到絕育目的，相當於給柳樹做了絕育手術（sterilization surgery）。

既然楊柳絮這麼惱人，能不能把楊樹柳樹都砍了呢？

Beijing has banned the planting of female poplars and has decided to increase the diversity of trees used in landscaping, but it has ruled out felling poplars and willows as they are a big part of the capital’s streetscapes and have adapted well to the environment.

北京已禁止種植雌株楊樹，並決定增加園林綠化樹木的多樣性。但由於楊樹和柳樹是北京街景很重要的一部分，且對環境適應良好，北京已排除了砍伐楊樹和柳樹的可能性。

中國工程院院士、著名林學家沈國舫表示，楊柳樹的生態作用遠遠大於飛絮的影響，治理楊柳飛絮千萬不能一砍了之。目前北京楊柳樹品種數量很多，且大都已經形成大樹，如果大量伐除這些樹木，不僅會引起城市環境質量和景觀的下降（damage environmental quality and urban landscape），還會造成更爲嚴重的生態損失（ecological loss）。

除了具有良好的景觀效果，楊柳樹還具有釋氧固碳（oxygen releasing and carbon fixation），降溫增溼（cooling and humidification）、減菌殺菌（reducing and killing bacteria），吸收有毒有害物質等顯著的生態功能。據介紹，楊樹和柳樹具有顯著的抗大氣污染的能力，對有害氣體（hazardous gas）、顆粒物（particles）及重金屬（heavy metal）的抗性和吸收吸附能力極強，是城市園林綠化的優良抗污樹種（pollution-resistant tree species），在抗大氣污染的某些能力方面優於國槐和側柏。

The government will also start a citywide inspection of the fire risks that come with catkins.

政府還將開展全市範圍的楊柳絮火災風險大檢查。

High-pressure water jets will be used to reduce floating catkins, and officials have asked the urban cleaning department to clear away the debris in a timely manner.

工作人員將使用高壓水槍減少飛絮，政府已要求環衛部門及時清理地面毛絮。

Cao Xiaojia, a doctor specializing in skin diseases at Chinese People's Liberation Army 306 Hospital in Beijing, said willow seeds are a common allergen in spring, with patients displaying symptoms such as red and itchy skin.

北京市解放軍第306醫院的皮膚病醫生曹曉佳說，在春天，柳絮是常見的過敏原，很多病人表現出皮膚髮紅瘙癢等症狀。

allergen ['ælədʒ(ə)n]：n. [醫]過敏原

"Those who are sensitive should take precautions such as wearing a mask when going out and avoiding eating spicy food," she said.

她說：“對其敏感的人們要採取防範措施，比如外出戴口罩，避免吃辛辣食物。”