自然教育要反思人与自然的关系

吴雯

在良渚自然学堂里，我们每次安排孩子到农园进行实际观察前，会组织他们讨论：你们觉得什么虫是害虫？孩子们非常天真地以昆虫对自己的好坏来判断，如他们认为菜青虫是害虫，因为它吃菜叶。

我问他们，菜青虫变成美丽的蝴蝶之后，就会帮植物传粉造福人类，它是害虫还是益虫呢？孩子们似乎有点明白了，即便都是从人类的角度来看，有害或有益也不是一成不变的。

有了这样一个思辨的基础，我们进一步带孩子考察发现不同的昆虫有哪些益处和害处。

苍蝇让人恶心，会传播各种疾病。但我用相机拍过上百种不同的苍蝇和它的“亲戚们”，这种广泛存在于自然界的双翅目昆虫，其实也是传粉的主力军。据统计，70%需要动物传粉的植物上，都有花虻的身影，而丽蝇是芒果不可替代的授粉昆虫。孩子们在对传粉昆虫调查时发现，除了蜜蜂、蝴蝶之外，传粉的昆虫多种多样，包括肉眼都看不清的蓟马，无处不在的蚂蚁，各种蜂、蛾子，也包括各种苍蝇。

毛毛虫常被归类为害虫，它们是鳞翅目蝴蝶或者蛾子的幼虫。它们虽然会吃掉农园植物一部分的叶子，但实际上它在整个生态链中它承担着食物提供者的角色。毛毛虫的蛋白质含量很高，是各种鸟类、蛙类的食物来源。尤其是大部分鸟类在繁衍后代的时候，都会以昆虫为主食。就算不使用农药，一般也不会出现某种农业虫害大面积爆发的情况。当孩子观察到菜青虫从卵到幼虫到蛹再到成虫的不同阶段，尤其是发现原来菜青虫是菜粉蝶的幼虫之后，他们再看见毛毛虫就不会一脚踩死，而是希望知道它们长大羽化之后，会成为哪种蝴蝶或者蛾子。

蚜虫一路伴随着植物的演化，发展成庞大的家族，已知种类有四千多种，寄生的植物包含了全部被子植物和松柏纲的所有科。蚜虫是演化得非常成功的一类昆虫：它们成群结队，用腹管吸食植物的汁液；它们繁殖最快，不但一年可以有30个世代，而且还具备孤雌繁殖等绝技；如果食物不够，它们还能长出翅膀，迁飞到其他植株。孩子们考察发现：蚜虫也是其他昆虫重要的食物供应者，会被食蚜蝇、瓢虫、寄生蜂、蟹蛛、草蛉等捕食；大部分蚜虫是單食性，而蚜虫的天敌们可以吃各种蚜虫，这样就不会出现蚜虫大面积爆发的情况。这些深入的观察可以让孩子们思考现代农业方面的问题，也许以后他们就能找到更合理的方式来应对所谓的农业害虫。

孩子们在农园发现，蚜虫有个“好朋友”——蚂蚁，它经常在植物上爬来爬去，原来它是在放牧蚜虫，为了吃蚜虫排出的蜜露。蚂蚁为此会在蚜虫的周围保护它们，与前来吃蚜虫的瓢虫“打架”。孩子们在翻地的时候挖出蚂蚁窝，发现它们是重要的分解者，会把小的果实、昆虫的尸体搬运到巢穴里面享用。孩子们还发现，蚂蚁还是了不起的土壤“工程师”，它们在地下的巢穴具备多个分区。

蛴螬也是常在地下被挖到的一种虫子，它主要吃植物的根，化蛹变成金龟子一类的成虫又会吃植物的叶子，这也是农业害虫。我每次挖到蛴螬都很开心，因为饲养后可以养出漂亮的甲虫。甲虫是生态系统里面的分解者，也给鸟类提供食物，它多样绚丽的外表，还提供了审美的价值。

人们把昆虫分为害虫和益虫，是从农业的需求来划分的。人类以为靠着杀虫剂、除草剂就能摒弃农作物的一切不利因素，却引发了更多的环境问题。其实昆虫在生态中拥有非常重要的功能，它们为植物传粉，它们给其他生物提供食物，有的是重要的分解者，有的是土壤“工程师”，有的是维护生态平衡的天敌昆虫，还有的甚至是我们审美的对象、灵感的源泉。

良渚农园很少使用农药化肥，用堆肥来改良土壤，用多样的植物为昆虫提供食物和栖息地，与昆虫分享植物。这样一个招蜂引蝶的农园，是自然教育、生态教育的良好场所，它能够激励孩子们走进自然，能够启发我们反思人与自然的关系，为我们提供一种超越人类中心主义的生态观。

Nature Education Should Reflect on the Relationship between Man and Nature

WU Wen

中图分类号：G424文献标识码：ADOI：10.16400/j.cnki.kjdk.2021.30.002

WU Wen

Founder of "Secret Land Guardian" of Environmental Protection and Nature Education Communication Organization

Founder of Liangzhu Nature School

Distinguished Expert of Natural Education in "Science and Education Guide"

In Liangzhu nature school， we organize our chil？ dren to discuss： what insects do you think are pests before we arrange them to go to the farm for actual observation？ Children are very naive to judge them？ selves by insects. For example， they think that Pieris rapae is a pest because it eats vegetable leaves.

I asked them， after the cabbage worm becomes a beautiful butterfly， it will help plants pollinate for the benefit of mankind. Is it a pest or a beneficial insect？ Children seem to understand that even from a human point of view， harmful or beneficial is not invariable.

With such a speculative basis， we will further take our children to investigate and discover the ben？ efits and harms of different insects.

Flies are disgusting and can spread all kinds of diseases. But I have photographed hundreds of differ？ ent flies and their "relatives" with my camera. This kind of Diptera Insect， which widely exists in nature， is actually the main force of pollination. According to statistics， 70% of plants that need animal pollina？ tion have the figure of gadfly， and lifly is an irre？ placeable pollination insect of mango. During the in？ vestigation of pollinating insects， children found that there are a variety of pollinating insects except bees and butterflies， including thrips that cannot be seen by the naked eye， ubiquitous ants， all kinds of bees， moths and all kinds of flies.

Caterpillars are often classified as pests. They are the larvae of Lepidoptera butterflies or moths. Al？ though they eat some leaves of farm plants， they actu？ ally play the role of food provider in the whole eco？ logical chain. Caterpillars have high protein content and are the food source of various birds and frogs. In particular， most birds will take insects as their sta？ ple food when they reproduce. Even if pesticides are not used， there will generally be no large-scale out？ break of certain agricultural pests. When children ob？ serve the different stages of Pieris rapae from egg to larva to pupa and then to adult， especially after they find that Pieris rapae is the larva of Pieris rapae， they will not step on the caterpillars again， but want to know what kind of butterfly or moth they will be？ come after they grow up and eclosion.

Along with the evolution of plants， aphids have developed into a huge family. There are more than 4000 known species. Parasitic plants include all an？ giosperms and all families of conifers. Aphids are a class of insects that have evolved very successfully： they flock and suck plant juice with their ventral tubes； They reproduce the fastest. They can not only have 30 generations a year， but also have unique skills such as parthenogenetic reproduction； If there is not enough food， they can grow wings and migrate tootherplants.Thechildren’sinvestigationfound that aphids are also important food suppliers for oth？ er insects， and will be preyed on by aphid flies， la？ dybugs， parasitic wasps， crab spiders and sandflies； Most aphids are monophagous， and their natural ene？ mies can eat all kinds of aphids， so there will be no large-scale outbreak of aphids. These in-depth obser？ vations can make children think about modern agri？ culture， and maybe they can find a more reasonable way to deal with the so-called agricultural pests in the future.

The children found that the aphid has a "good friend" - ant. It often crawls around on plants. It turns out that it is grazing aphids in order to eat the honeydew discharged by aphids. For this reason， ants will protect them around aphids and "fight" with lady？ bugs who come to eat aphids. Children dig out ant nests when turning over the ground and find that theyareimportantdecomposers.Theywillcarry small fruits and insect bodies to the nest for enjoy？ ment.Thechildrenalsofoundthatantsarealso great soil "engineers"， and their underground nests have multiple zones.

Grub is also a kind of insect often dug under？ ground. It mainly eats plant roots， pupates into bee？ tles， and adults will eat plant leaves， which is also anagriculturalpest.Everytimetheauthordigs grubs， she is very happy， because after feeding， the author can raise beautiful beetles. Beetles are decom？ posers in the ecosystem and provide food for birds. Their diverse and gorgeous appearance also provides aesthetic value.

Insects are divided into pests and beneficial in？ sects according to the needs of agriculture. Humans think that relying on pesticides and herbicides can abandonalladversefactorsofcrops，butithas caused more environmental problems. In fact， insects have very important functions in ecology. They polli？ nateplantsandprovidefoodforotherorganisms. Some are important decomposers， some are soil "engi？ neers"， some are natural enemies to maintain ecologi？ cal balance， and some are even the object of our aes？ thetics and the source of inspiration.

Liangzhu agricultural park rarely uses pesticides and chemical fertilizers， uses compost to improve the soil， uses a variety of plants to provide food and hab？ itat for insects， and shares plants with insects. Such an agricultural garden that attracts bees and butter？ flies is a good place for natural education and ecolog？ ical education. It can inspire children to enter na？ ture， inspire us to reflect on the relationship between man and nature， and provide us with an ecological view beyond anthropocentrism.