Khaled Sleem Graduated from the Faculty of agriculture and food sciences as Agriculture engineer in 1995 worked in the agricultural sector for 4 years in the Bekaa Valley, then joined a team of researchers at AUB in March 2002 with whom started a multidisciplinary center whose main interests are studies related to nature conservation, during his long journey he was exposed to many expertise in reforestation, medicinal plants, domestication of wild herbs and trees, essential oil production, Biodiversity (specialized in the Lebanese flora), composting and vermicomposting. With a group of researchers at AUB published two books: Trees of Lebanon, and Plants and people.
In 2011 he started a native trees private nursery (Native nurseries, www.native.com.lb); he helped in many reforestation projects. Last but not least, developed deep interest in the field of sustainable agriculture, mainly agro-ecology a field that involves all aspects of production in a harmony where each element of the farm works for the resilience of the whole.
With nine other nurseries started the Cooperative of Native Tree Producers in Lebanon (CNTPL)
Khaled Sleem is an active member in the Lebanon Reforestation Initiative.