Abstract:

Based on the biodiversity characteristics in the Three Rivers Headstream Region, we calculated the irreplaceability values in conservation planning units of the region by using GIS and C-Plan conservation planning software under the framework of systematic conservation planning (SCP) methods, and further calculated the contributions of the existing Nature Reserve in the Three Rivers Headstream, analyzed the complementarity of main protected object between any two subareas and efficiency of each zone, and identified conservation gaps in the study area with the calculated irreplaceability values. The nature reserve contribution assessment showed that the existing two main protected areas covered all the surrogates identified in this study, and protected 80% of the surrogates that the conservation target planned to do. The high irreplaceability areas roughly corresponded to the core zones of the existing nature reserves in their spatial distribution. The contributions of core zones, core zones + buffer zones,and core zones + buffer zones + experiment zones were 61.20%, 77.57% and 91.20%, respectively. Core zones in six subareas of the Three Rivers Headstream Nature Reserve were highly complementary, suggesting that the core zone classification was reasonable and the identification of main protected objects was obvious. GAP analysis indicated that 8.08% of the total targets were not yet fulfilled and 20% of the surrogates were underrepresented, including one ecosystem type and 7 species. The gaps were mainly distributed in Tanggula region characterized by lakes, glaciers, snow mountains and alpine meadows, Yuegai-Bagan region with alpine meadows as main vegetation type, Zeku-Henan alpine shrub and meadow region, and Longbao-Laxiu forest and shrub region.

Key words: biodiversity in Three Rivers Headstream Region, C-Plan, irreplaceability, contributions, conservation gaps