大风沙尘天气刚过，春天的烦恼还没结束——你花粉过敏了吗？
每年春天，都有人戴着口罩红着眼，控制不住地打喷嚏、流鼻涕，严重的甚至可能造成哮喘、呼吸困难等……
春季是花粉过敏的高发季节。花粉过敏是由风媒传粉植物引起的，这些植物释放大量花粉，影响到人们的鼻腔、眼结膜和气道。
在北京天坛公园，柏树飘落下大量花粉 图源：新华社 以下同
日益增长的花粉过敏背后，最直接的原因是花粉量的增加。北京协和医院变态（过敏）反应科主任关凯在接受新华网采访时表示，全球“变绿了”，加上随着全球变暖，植被的生长周期变长，花粉季也变长了，这也导致过敏原变得越来越多。
Spring is a peak season for pollen allergies, primarily caused by wind-pollinated plants that release large amounts of pollen, affecting people's nasal passages, eyes and airways. The most direct cause behind the increasing cases of pollen allergies is the rise in pollen levels. Guan Kai, director of the Allergy Department at Peking Union Medical College Hospital, told Xinhua News Agency that the world is "greening", and with global warming, the growth cycles of vegetation have been extended, lengthening the pollen season. Consequently, allergens are becoming more abundant.
花粉季的花粉浓度偏高。花粉浓度是指每1000平方毫米所含有的花粉粒数，一旦空气中主要致敏花粉超过100粒/1000平方毫米，就标志着该地区进入花粉期，超过400粒/1000平方毫米则表明花粉浓度已经偏高了。
以北京为例，每年3月中旬到4月中旬，柏树花粉、榆树花粉等致敏花粉浓度持续处于高峰。“花粉监测预报”公众号显示，预计北京部分地区4月13日花粉浓度等级在3~5级，为中等到很高级别（251~1200粒/1000平方毫米）。
除了主动防护、治疗，科学家们也来帮忙治理过敏原啦！
我们应该如何预防过敏呢？除了减少外出、佩戴防护用品、及时清理、就医等自我防护措施以外，科学家们也正在努力探索研究，以有效治理过敏原。
以圆柏为例，圆柏花粉数量多、颗粒小，集中散布时就像“沙尘暴”一般，是北京花粉致敏的主要成分之一。
Take the example of juniper. Its abundant pollen, though small in size, can spread like a "sandstorm" when released in large quantities. Juniper pollen is one of the main components causing allergic reactions in Beijing this year.
不少受花粉过敏折磨的网友发问：“就不能把北京的圆柏全拔了吗？”
据统计，北京现存古树中有侧柏古树22000株、圆柏6000株。诚然，解决过敏源头是一种思路。但砍伐或大规模改造古柏既不符合法律规定，又会对生态造成严重影响。
既要保护生物多样性，又要兼顾人类自身健康，那我们该如何与圆柏共处？
圆柏花粉治理的思路主要基于花粉源头防治、增加及时沉降及延缓释放时间三个方面。
The strategy for managing juniper pollen focuses on three aspects: controlling the source of pollen, increasing timely pollen deposition and delaying the release time.
源头控制，培育新品种，减少雄花数量
圆柏分雌株和雄株，其中雌株不飞粉，雄株有小孢子叶球结构，是花粉产生的源头。
北京农学院植物科学技术学院秦岭教授团队此前对板栗雄花序调控的研究为治理圆柏花粉提供了新灵感。
“我们基于板栗短雄花序芽变种质的发现，研发出板栗‘促雌减雄’技术，从而培育出了板栗雄花序败育新品种。对于圆柏雄株，我们在雄株小孢子叶球形成的关键期进行抑制，使其数量减少至原来的20%，从根源上减少花粉量。”
Junipers are divided into male and female plants. The female plants do not produce pollen, while the male plants have microsporangiate strobilus structures that are the source of pollen production. Professor Qin Ling's team from the School of Plant Science and Technology at Beijing Agricultural University has conducted research on regulating the catkins of chestnut trees, which has inspired new approaches to managing juniper pollen. "Based on the discovery of short male catkin bud variants in chestnuts, we developed a 'promote-female and reduce-male' technology to cultivate new varieties with sterile male catkins," Qin said. "For male junipers, we can inhibit the formation of microsporangiate strobilus at critical stages, reducing their number to 20 percent of the original, thereby decreasing pollen production at the source."
途中抑制，更高效的花粉固定剂抑制花粉飘散
近日，秦岭教授团队已研发出高分子有机化合物花粉固定剂，将其喷洒在圆柏雄株小孢子叶球表面，形成一层包裹膜，就像为树戴上了“口罩”，能有效遏制柏树花粉飘散。
团队成员、农学院教授邢宇介绍，实验显示，喷花粉固定剂沉降花粉的效果是喷水的17至20倍。
该成果有望明年率先在北京市西城区、东城区、朝阳区等6个区使用。
早期预警，及时采取预防措施
除了源头控制花粉、中途调控减少花粉，还可以在花粉形成后减少其浓度，目前主要的方式就是无污染的喷水方式，适合需要重点保护的圆柏古树。
在北京红领巾公园内，工作人员喷淋开花的柏树
国家自然博物馆联合北京植物学会，与中国科学院华南植物园合作，共同发起“北京圆柏分布调查”公民科学项目，结合信息技术手段发动公众对圆柏进行地面观测，有望实现更早期的精准预警，也为未来花粉过敏原的科学治理提供研究和决策支持。
In addition to controlling pollen at the source and reducing it midway, another effective method is to decrease the pollen concentration after it has formed. The main approach currently is to use non-polluting water spray, which is particularly suitable for protecting ancient juniper trees. The National Museum of Natural History, in collaboration with the Beijing Botanical Society and the South China Botanical Garden of the Chinese Academy of Sciences, has launched a citizen science project called the "Beijing Juniper Distribution Survey". This project utilizes information technology to engage the public in ground observations of junipers. It aims to achieve earlier and more precise pollen warnings and provide research and decision-making support for the scientific management of pollen allergens in the future.
中国科学院华南植物园标本馆工程师徐洲锋表示，通过圆柏植株物候的地面观测，可以捕获更加准确的植物物候信号，汇聚大规模的局地植株物候数据，就有可能更加准确的推测圆柏的传粉时间，从而做到更早期的预警。
国家博物馆副研究员刘晓丽表示，圆柏花粉散播的时间在不同年份虽然差异不是太大，但是对于过敏群体来说，越早的预警受益会越大。如果能够做到未雨绸缪，让过敏的人能够提前做好准备或者能够提取对植株进行一定的处理，比如喷水沉降、定期剪枝、喷洒花粉固定剂等，相信很多人的春天会更好过一些。
Xu Zhoufeng, an engineer at the Herbarium of the South China Botanical Garden of the Chinese Academy of Sciences, said that ground observations of juniper phenology can capture more accurate phenological signals of the plants. By aggregating large-scale local phenological data of junipers, it is possible to more accurately predict the pollination time, thereby providing earlier warnings. Liu Xiaoli, an associate researcher at the National Museum of China, said that although the pollen dispersal times of junipers do not vary significantly from year to year, earlier warnings would greatly benefit allergy sufferers. If we can prepare in advance, allowing individuals to take measures such as using water sprays, regularly pruning, or applying pollen fixatives to plants, many people will have a better time during spring.
记者：闫东洁
China Daily精读计划
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