Strategies for Setting Conservation Target in Human Dominated Landcover Areas for Systematic Conservation Planning at the Regional Scale

Non-natural areas as well as natural areas at the regional scale can be important when species migrate to find new habitats as a result of climate change. It is necessary that areas dominated by agricultural and urban land cover should be considered as areas for conservation practices, such as the protected areas based on the systematic conservation planning (SCP). The selection of conservation targets is a necessary step for SCP. Researchers have assigned target species based on the degree to which they are endangered (Variable), while others have considered all species equally (Uniform). In natural areas, the conservation network results differ depending on the conservation target selected. However, the effects of different target types and values are not known for areas dominated by anthropogenic land cover. Therefore, we investigated the effect of different conservation targets in areas dominated by urban, agriculture, and forest land cover.

In each type of land cover, a total of twenty conservation target scenarios were created (ten for each of the two types of conservation targets) by the target values. In the uniform scenario, the same target was allocated to all species (from 10% to 100%), whereas in the variable scenario, targets were assigned according to the degree of the IUCN Red List (from 0.9-10% to 9-100%). Prioritization was implemented using MARXAN 100 times. We compared the sum of the number of planning units that were not selected at all (No_PUs) and those that were selected more than 90 times (90_PUs) among the scenarios.

In all three landscapes, the uniform scenarios increased the sum of No_PUs and 90_PUs when conservation target was increased, whereas the variable scenarios decreased those. Variable targets were effective to draw more diverse conservation networks. However, the average of the sum of No_PUs and 90_PUs was different depending on the dominating land cover, the order was agriculture (93%) > urban (87%) > forest (81%). This means that the proposed conservation networks in agriculture and urban had the more certainty than forest and were less sensitive with conservation targets. Therefore, in areas affected by human activities SCP can derive more obvious conservation plans, while in natural areas can draw more diverse conservation plans, which help to persuade diverse stakeholders.