Yaduwar muhali

A cikin ilimin muhalli, kalmar **yawan aiki** ranar nufin yawan ƙarni na biomass a cikin tsarin halittu, yawanci ana bayyana shi a cikin raka'a na taro a kowane girma (ɗaya) a kowane raka'a ta lokaci, kamar grams a kowace murabba'in mita a kowace rana (g m-2 d-1). Rukunin taro na iya danganta da busassun abu ko kuma tarin carbon da aka samar. Ayyukan autotrophs, kamar shuke-shuke, ana kiransu yawan aiki na farko, yayin da yawan aiki na heterotrophs, irin su Dabbobi, ana kiransa yawan aiki na biyu.

Ayyukan da ke cikin yanayin halittu suna rinjayar abubuwa da yawa, gami da wadatar abinci mai gina jiki, zafin jiki, da wadatar ruwa. Fahimtar yawan amfanin muhalli yana da mahimmanci saboda yana ba da fahimta game da yadda tsarin halittu ke aiki da kuma yadda zasu iya tallafawa rayuwa.

## Aikin farko
Samar da farko shine kira na kayan kwayoyin halitta daga kwayoyin inorganic. Samar da farko a mafi yawan yanayin halittu ya mamaye tsarin photosynthesis, wanda kwayoyin ke hada kwayoyin halitta daga Hasken rana, H2O, da CO<sub>2</sub>.  Ayyukan farko na ruwa suna nufin samar da kwayoyin halitta, kamar su phytoplankton, tsire-tsire na ruwa, da algae, a cikin yanayin halittu na ruwa, wanda ya haɗa da teku, tabkuna, da koguna. Amfanin farko na ƙasa yana nufin samar da kwayoyin halitta wanda ke faruwa a cikin yanayin halittu na ƙasa kamar gandun daji, wuraren ciyawa, da wuraren da ke da ruwa.

An raba samar da firamare zuwa Net Primary Production (NPP) da Gross Primary Producation (GPP). Girman samar da farko yana auna duk carbon da aka daidaita a cikin kwayoyin halitta ta masu samar da farko. Net primary samar da auna kwayoyin kwayoyin halitta ta hanyar masu samar da farko. Har ila yau, samar da farko na yanar gizo yana auna adadin carbon da aka daidaita a cikin kwayoyin halitta ta hanyar masu samar da farko, amma ba ya haɗa da kwayoyin halitta waɗanda waɗannan kwayoyin suka sake karyawa don matakai na halitta kamar numfashi na salula. Tsarin da aka yi amfani da shi don lissafin NPP shine samar da farko = samar da farko - numfashi.. 

### Masu samarwa da farko

Kwayoyin da suka dogara da makamashi mai haske don gyara carbon, don haka shiga cikin samar da farko, ana kiransu photoautotrophs.

Photoautotrophs ya wanzu a fadin itacen rayuwa. Yawancin ƙwayoyin cuta an san su da photoautotrophic kamar cyanobacteria  da wasu Pseudomonadota (tsohon proteobacteria).  Kwayoyin eukaryotic sun sami damar shiga cikin photosynthesis ta hanyar ci gaban plastids da aka samo daga dangantakar endosymbiotic. Archaeplastida, wanda ya haɗa da ja algae, kore algae, da tsire-tsire, sun samo asali ne daga chloroplasts wanda ya samo asali ne kawai daga tsohuwar dangantakar endosymbiotic tare da Alphaproteobacteria .  Ayyukan shuke-shuke, yayin da suke photoautotrophs, sun dogara da dalilai kamar salinity da abiotic stressors daga mahalli da ke kewaye. Sauran kwayoyin eukaryotic photoautotrophic suna cikin SAR clade (Comprising Stramenopila, Alveolata, da Rhizaria). Kwayoyin da ke cikin SAR clade waɗanda suka haɓaka plastids sun yi hakan ta hanyar dangantaka ta biyu ko ta uku tare da algae mai kore da / ko ja algae. Ƙungiyar SAR ta haɗa da masu samar da ruwa da ruwa kamar Kelp, Diatoms, da Dinoflagellate.
## Manazarta