Complex sentence: In the Elburz Range forest steppe ecoregion, the higher elevations are arid with few trees; but in the northern slopes, the Caspian Hyrcanian mixed forests ecoregion is lush and forested.
Split into simpler sentences: In the Elburz Range forest steppe ecoregion, the higher elevations are arid with few trees. But in the northern slopes, the Caspian Hyrcanian mixed forests ecoregion is lush and forested.