Az rastanihoe, ki to alhol shinos shudaed, luchtukhmon bo doshtani tukhm farq mekunand. Inchunin, luchtukhmon az ushnaho, chilband va sarakhsho bo on farq mekunand, ki dar onho baroi bordor shudani hujayratukhm qatrai ob hamchun omili muhim digar zaruriyat nadorad. In holat ba rastanihoi luchtukhm imkon dod, ki dar min- taqahoi …

Archa rastanii (darakhti) hameshasabz buda, ba sinfi suzanbargon dokhil meshavad. Helhoi on asosan darakht yo buttashakl buda, bazan khobravanda meshavand. SHaklhoi darakhtii on 10-12 m va hatto to 20-30 m ba bolo qad mekashand. Barghoi aksari rastanihoi javoni archa dar solhoi avvali sabzishashon suzanmonand buda, bad shakli pulakcharo megirand. Dar …

Darakhti archa ba monandi digar rastanihoi suzanbarg asosan tavassuti tukhmash afzoish mekunad. Tukhmi archa dar pulakchahoi chalguzaash ba tavri kushod (yane luch) joygir ast. Az in ru, archa va digar rastanihoi suzanbargro rastanihoi luchtukhm nom mebarand. Archa rastanii dukhonagi, bazan yakkhonagi meboshad. Pulakchahoi khurd (mikrosporofill) dar chalguzai (mardonai) khurdi tukhmshakl …

Taqriban 300 million sol muqaddam dar hama joi sathi Zamin tamomi sol havoi garmu serrutubat hukmron bud. Bar asari boridani boronhoi garmu omadani sel daryoho serob shuda, kulho va botloqzaminho paydo shudand. Tumani tirai bukhori ob aksar vaqt oftobro panah mekard. CHunin sharoit boisi nashunamoi boavji nabototi nazdisohili va botloqi, …

CHilband yo chilbugum giyohi bisyorsola buda, chun sarakhsshaklon rastanihoi khele qadima ba khisob meravand. Onho takriban 32 namudro tashkil doda, dar bisyor mamlakathoi jahon, ba juz Avstraliya va Zelandiyai Nav, meruyand. Dar Tojikiston du namudi on chilbandi sahroi va shokhronda mesabzad. Balandii poyai chilbaclindho az 80 to 100 sm buda, …

Sarakhsho ba guruhi rastanihoi qadimtarin dokhil meshavand. Onho dar rui Zamin vase pahn gardidaand. Dah hazor kheli onho malum ast. Dar sharoithoi gunoguni zist, dar biyobon va botloqzorho, kulho, maydonhoi kishti sholi, obhoi nisbatan shur, dar joyhoi sernamu soyai darakhtoni beshazor sukunat dorand. Sarakhsho dar mintaqahoi kuhsor, dar joyhoi sernamu …

Ushnai torfi yo sfagnum chun digar namudi ushnaho boshandagoni botloqzorho meboshad. On taqriban 300 khelro darbar megirad. Ushnai torfiro bo iborai digar ushnai safed ham meguyand, chunki dar holati khushk budanash rangi zardu safed yo bo purragi safedro dorad. Dar botloqzorhoi sernam sfagnum pushishi qolinmonandi yaklukhtro paydo mekunad. Dar on …