Thanks for your interest in the International Network on Salt-Affected Soils (INSAS).
Please note that to become INSAS member, your organization/institution should first become a partner of the Global Soil Partnership (GSP).
You can check the list of already registered GSP partners at this link:
http://www.fao.org/global-soil-partnership/partners/gsp-partners/en/At the same link you will find information on how your organization/institution can register as GSP partner.