Water cycle aur groundwater

Sooraj paani ko chalata hai

Dhoop waale din geele kapde jaldi sookhte hain, kyunki Sooraj ki garmi evaporation tez kar deti hai. Yahi garmi samudron, nadiyon aur jheelon ka paani lagaataar bhaap banaati hai. Prakriti mein paani teen roop mein hai: samudron aur nadiyon mein liquid, pahaadon aur dhruvon par barf ke roop mein thos, aur hawa mein bhaap ke roop mein gas. Garmi mein kuch barf pighal kar nadiyon ke roop mein behti hai; sardi ki nayi barf uski bharpaai karti hai.

Water cycle

• Evaporation: samudron, nadiyon aur jheelon ka paani Sooraj se garam hokar bhaap bankar uthta hai.
• Transpiration: ped aur paudhe bhi bhaap chhodte hain.
• Condensation: upar uthti bhaap thandi hokar chhoti boondein banti hai, jinse baadal bante hain.
• Precipitation: baadal paani ko baarish, barf ya ole ke roop mein neeche laate hain.
• Wapas: baarish ka paani taalaabon, nadiyon aur samudron mein behta hai, ya zameen mein risata hai.

Ye lagaataar chakkar water cycle hai. Ye paani ko samudron se zameen tak aur wapas le jaata hai, nadiyon, jheelon aur zameen ko bharta hai, aur Dharti par paani ki kul maatra ek jaisi rehti hai. Bahut pehle, 6th century CE mein, Ujjaini ke khagolshaastri aur ganitagya Varahamihira ne apni kitaab Brihatsamhita mein baadal, hawa, taaron aur Chaand ko dekh kar mausam ki baarish ka andaaza lagaane ke tareeke bataaye.

Paani zameen mein kaise risata hai

Activity 7.5 mein plastic ki teen kati, ulti botlon mein clay, ret aur gravel bhar kar tulna ki jaati hai. Har botal mein utna hi paani daala jaata hai, aur 10 minute mein tapakne waala paani jama kiya jaata hai.

Botal	Paani kitni tezi se risata hai
Gravel	tez
Ret	dheere
Clay	sabse dheere

Gravel ke tukdon ke beech chaudi, khuli aur judi jagah hoti hai, isliye paani aasaani se nikal jaata hai; clay ke kanon ke beech sirf bahut chhoti daraarein hoti hain. Zameen ki satah ke paani ka mitti aur chattaanon se risna infiltration hai.

Groundwater aur aquifers

Neeche risa paani mitti ke kanon ke beech ki jagah mein aur chattaanon ki daraaron mein jama hota hai. Ye groundwater hai. Jo parat ise rakhti hai wo aquifer hai. Kuen, handpump aur borewell aquifers tak pahunch kar paani nikaalte hain, jo kuch metre se lekar saikdon metre neeche tak ho sakta hai.

Groundwater bachaana

Groundwater asimit nahi hai. Badhti aabaadi zyaada se zyaada paani nikaalti hai, shaharon mein kam ped aur zyaada concrete hone se kam baarish ka paani zameen mein risata hai, aur isliye groundwater ka star gir raha hai. Rainwater harvesting baarish ke paani ko behne dene ki jagah jama karti hai, aur recharge pits use wapas zameen mein risne dete hain.

Ladakh mein vasant mein nadiyan aksar sookh jaati hain, kyunki tab Sooraj itna tez nahi hota ki pahaadon ki barf pighla sake. Sardi mein log nadi ka paani pipe se neeche laakar jamaane waali thandi hawa mein phuhaar maarte hain, jahan wo parat dar parat jamkar ek ooncha cone banata hai, jise ice stupa kehte hain. Ye vasant mein dheere pighalta hai aur poori garmi kheti ke liye paani deta hai.

Ye kyun zaroori hai

Water cycle ki wajah se hi baarish aati rehti hai aur kuen hamesha ke liye nahi sookhte. Paani kaise chalta hai aur zameen kitni dheere bharti hai, ye jaankar hum paani soch-samajhkar use kar sakte hain, chaahe school mein baarish ka paani jama karke ya ghar mein paani barbaad na karke.

Thos, liquid aur gas mein garmi kaise chalti hai, ye padho conduction, convection aur radiation mein. Textbook ke sawaalon ke jawab Chapter 7 ke NCERT solutions mein hain; poore chapter ke liye Chapter 7 ke notes.