Keywords
Abstract
Tuproq namligi ifloslantiruvchi moddalarning migratsiyasi, tuproqdagi kimyoviy va biologik jarayonlar hamda o‘simliklarning suv bilan ta’minlanishini belgilovchi asosiy omillardan biridir. Ushbu ishda Toshkent shahri Sergeli tumani hududidan 0–20 va 20–40 sm chuqurlikdan olingan 18 ta tuproq namunasining namligi termostat-tortish (gravimetrik) usulida aniqlandi va solishtirma sirt yuzasiga asoslangan adsorbsion model natijalari bilan solishtirildi. Namunalarning namligi 4,78–7,16% oralig‘ida bo‘lib, 0–20 sm qatlamda o‘rtacha 5,67 ± 0,57%, 20–40 sm qatlamda 6,25 ± 0,60% ni tashkil etdi. Chuqur qatlamda namlik 0,58% ga yuqori bo‘ldi (effekt kattaligi d = 0,99), ammo Welch t-testi bo‘yicha farq statistik ahamiyatlilik chegarasida qoldi (p = 0,055). Adsorbsion model bo‘yicha solishtirma sirt yuzasi 70 m²/g bo‘lgan gilli tuproq 4,2–14,0%, 7 m²/g bo‘lgan qumli tuproq esa 0,35–1,05% suvni adsorbsion bog‘lab olishi mumkin. O‘lchangan namlik gilli tuproq uchun 0,68–1,02 nm qalinlikdagi, ya’ni 2–4 molekula qatlamiga teng suv pardasiga mos keladi. Bu natija namunalardagi suvning asosiy qismi tuproq zarralari sirtida bog‘langan holatda bo‘lishi mumkinligini ko‘rsatadi. Taklif etilgan yondashuv gravimetrik o‘lchovlarni tuproq granulometrik tarkibi bilan birgalikda talqin qilish va ekologik monitoringda suvning harakatchan ulushini baholash imkonini beradi.
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