MAHSULNOKII BIOLOGI, mafhumi ekologi va umumibiologiest, ki tajdidi (az nav barqaror kardani) biomassahoi nabotot, mikroorganizmho va hayvonoti ba ekosistema dokhilshavandaro ifoda mekunad; ba manoi mahdudash — tajdidi hayvonoti vahshi va nabototi khudruest, ki inson istifoda mebarad. Mahsulnokii biologi dar har yak mavridi judogona az rui surati tajdidi populyasiyahoi namudhoi nabotot va hayvonot amri voqe megardad, ki on ba surati muayyan surat megirad. In surat bo buzurgii muayyan — mahsuloti yaksola (yo mahsulote, ki bo digar vohidhoi vaqt chen shudaast), bo vohidi masohat (baroi makhluqote, ki dar khushki va qari ob zindagi mekunand) yo vohidi hajm (baroi organizmhoe, ki dar ob va daruni khok maskunand), ifoda karda meshavad.