BiologyBhanu · Class 4-5
Khaane ki kadi se khaane ka jaal: utpaadak, upbhokta, apghatak
Aman ke gaon mein ek saal bahut saare mendak kam ho gaye. Agle saal khet mein keede itne badh gaye ki fasal kha gaye. Aman ne apne papa ka udaas chehra dekha aur socha: mendak aur fasal ka kya rishta?
Socho pehle… phir dekho jawab
Gaon ki krishi didi ne samjhaya: mendak keede khaate the. Mendak kam hue, phir keede badhe, phir keedon ne fasal khaayi, isliye kisaan ka nuksaan. Ek kadi ka ek jeev hilta hai, toh poora jaal hilta hai.
Krishi didi ne zameen pe lakdi se teer banaaye: suraj → ghaas → tidda → mendak → saanp. "Yeh khaane ki kadi (food chain) hai. Har teer ka matlab 'iska khana banta hai'." Aman ne ghaas ki ek patti todi. Didi boli, "Hare paudhe utpaadak (producer) hain — suraj ki roshni, paani aur hawa se khana banate hain. Jo khaate hain, woh upbhokta (consumer): tidda paudhe khaata hai, mendak tidde ko."
Aman ne socha, "Toh bas ek seedhi line hai?" Phir usne khet mein dekha: ek chidiya bhi tidda pakad rahi thi, aur mendak bhi ek nanha keeda pakad raha tha. Didi muskurayi, "Asli jungle ya khet mein ek jeev kai cheezein khaata hai, aur use kai jeev khaate hain. Isliye kadiyan aapas mein jud kar jaal banati hain — khaane ka jaal (food web). Jaal jitna bada, utna majboot: ek jeev kam ho toh doosra raasta bacha rehta hai."
Phir didi ne khet ke kinaare gire patton ka dher hataaya. Neeche ki mitti naram aur kaali thi. "Teesra group sabse chhupa hua hai: apghatak (decomposer) — mitti ke bacteria aur fungus. Yeh gire patte, sadte phal aur chhilkon ko tod kar mitti ko phir se poshak banate hain." Aman hairan hua jab didi ne bataya ki ek bade ped ke neeche ki ek mutthi mitti mein itne apghatak jeev hote hain jitne duniya mein log!
Ab Aman samajh gaya. Usne apne doston ke saath khet ke kinaare ka talaab saaf rakha, taaki mendak laut aayein. "Yeh mere khet ke chaukidaar hain," usne garv se kaha.
Tum Aman hote toh mendakon ko khet ke paas waapas bulaane ke liye aur kya karte?
Humne kya kiya :- Mendak kam hone se fasal tak ki kadi peeche jaakar dekhi aur jaal banaya.
Isse kya hua :- Samjhe ki har jeev ka ek kaam hai — utpaadak, upbhokta ya apghatak — aur jaal mein sab jude hain.
Ghar pe try karo
Ek chaukor kaagaz par beech mein 'suraj' likho. Bade ke saath aangan, park ya khet mein 10 minute mein jo jeev dikhein (ghaas, ped, cheenti, keeda, titli, chidiya, gilahri, gaay) unke naam chaaron taraf likho. Ab teer kheencho: kaun kisko khaata hai. Kitne teer bane? Yahi tumhara khaane ka jaal hai.
Wow!
Ek bade ped ke neeche ki ek mutthi mitti mein itne apghatak jeev hote hain jitne duniya mein log — aur woh har saal poore jungle ke gire patte saaf kar dete hain!
Mummy-Papa ke liye
Aaj bachche ke saath thali ki teen cheezon ki kadi peeche tak banwaaiye (dahi, roti, sabzi) aur poochhiye: 'Sookha patta aur chhilka kis group ka khana hai?'
3 sawaal
- Khaane ki kadi mein utpaadak (producer) kaun hai?
Jawab dekho
Hara paudha. Sirf hare paudhe suraj ki roshni se khana banate hain; baaki sab upbhokta hain.
- Mitti ke bacteria aur fungus kya kaam karte hain?
Jawab dekho
Gire patte aur sadte phal tod kar mitti ko poshak banate hain. Yeh apghatak (decomposer) hain — kadi ko mitti par poora karte hain.
- Khaane ka jaal (food web) kyun zyada majboot hota hai?
Jawab dekho
Ek jeev kam ho toh doosre raaste bache rehte hain. Jaal mein har jeev ke kai khane aur khane wale hote hain, isliye ek kadi tootne par poora jaal nahi tootta.
NCERT se jodo: NCERT Class 4-5 EVS — paudhe, jaanwar aur unka khana; Class 7 Science ka 'paudhon aur jaanwaron mein poshan' wala vichar (idea in words)