Journal of Geographical Sciences >
Identifying multispecies dispersal corridor priorities based on circuit theory: A case study in Xishuangbanna, Southwest China
*Corresponding author: Liu Shiliang (1976-), PhD and Professor, E-mail: shiliangliu@bnu.edu.cn
Author: Yin Yijie, (1991-), Master Student, specialized in environmental sciences and landscape ecology. E-mail: yijieyin@126.com
Received date: 2018-05-10
Accepted date: 2019-01-22
Online published: 2019-07-25
Supported by
National Natural Science Foundation of China, No.41571173
National Key Research and Development Project of China, No.2016YFC0502103
Copyright
Ecological corridor networks can efficiently improve regional landscape connectivity. Corridors for multiple faunal species movements are receiving increasing attention and graph theory is considered a promising way to explore landscape connectivity. In Xishuangbanna, the circuit theory was applied to explore the corridor networks for biodiversity for the first time. In addition, disturbances caused by the road network and the protection efficiency of National Nature Reserves and planned area for corridors were evaluated. Results indicated that the regional corridor networks could be estimated using a modified circuit method and Zonation model. Spatially, the key corridors were concentrated in the central-western, southeastern and northern regions. We detected 66 main intersections between key corridors and the road buffer. Of these points, 65% are forest, 23% grassland and 12% farmland. More than half of the area of National Nature Reserves constituted the top 50% of the corridors, and the planned corridor areas could efficiently protect some key corridors. However, these reserves only protected about 17% of regional key corridors, and the corridor conservation area in the western and northern regions were absent. The issues addressed in our study aided in the elucidation of the importance of regional landscape connectivity assessments and operational approaches in conservation planning.
YIN Yijie , LIU Shiliang , SUN Yongxiu , ZHAO Shuang , AN Yi , DONG Shikui , Ana COXIXO . Identifying multispecies dispersal corridor priorities based on circuit theory: A case study in Xishuangbanna, Southwest China[J]. Journal of Geographical Sciences, 2019 , 29(7) : 1228 -1242 . DOI: 10.1007/s11442-019-1655-5
Figure 1 Location of the study area |
Table 1 The assignment of permeability values |
Factors | Variables | Permeability |
---|---|---|
Land use | Cultivated land | 100 |
Forest | 1000 | |
Grassland | 1000 | |
Shrubland | 1000 | |
Wetland | 1000 | |
Water body | 10 | |
Artificial surface | 10 | |
Roads | First level | 10 |
Second level | 100 | |
Third level | 1000 | |
Terrain feature | 0<TRI≤5 | 1000 |
5<TRI≤10 | 100 | |
TRI>10 | 10 |
Figure 2 The appropriate current density map for multiple species in Xishuangbanna |
Figure 3 Locations of local representative species |
Figure 4 The current-specific curve derived from basic Zonation output |
Figure 5 Ranking result of corridors derived from the Zonation analysis (a). The top 20% of the potential corridors which were viewed as key corridors and the block points were marked as green points (b). Those marked with numbers were farmland block points. |
Table 2 Proportions of potential corridors for different ranking levels in each national nature reserve (%) |
Corridor ranks | Mengyang | Mengla | Shangyong | Menglun | Mangao |
---|---|---|---|---|---|
< 50% | 48.3 | 43.5 | 13.8 | 28.3 | 2.3 |
> 50% | 51.7 | 56.5 | 86.2 | 71.7 | 97.7 |
> 80% | 21.3 (6.3) | 19.6 (5.9) | 29.3 (2.6) | 23.1 (0.7) | 46.6 (1.2) |
Percentage of total key corridors | 4.6 | 7.2 | 3.7 | 0.8 | 0.9 |
Note: Numbers in brackets are the proportions of the total key corridors of the whole study area. Other numbers only considered the corridors within each reserve. “> 80%” in this table means the same with “top 20%”. |
Figure 6 The comparison of planned corridor areas and key corridors |
Figure 7 Comparisons of correlation coefficients between the first and second trials with the same number of nodes (a); correlation coefficients between 50 nodes and fewer nodes number (b) |
Figure A1 Top 20% of the potential corridors were extracted and classified into two levels (0.8-0.9 and 0.9-1). The block points were marked as the green points according to following standards (these standards must be satisfied at the same time):All the intersections should locate at top 10% area (0.9-1). There should be at least 5 top 10% grids in a 3 × 3 road grid which surrounds the target intersection. Compared with the situation in the 3 × 3 road grid, it is supposed to increase at least 1 key corridor grid that belongs to top 20% in a 4 × 4 road grid which includes the compared 3 × 3 road grid. Any two intersections are at least 400 m apart. |
Figure A2 Details of the distribution of key corridors (top 20%) in each reserve (Mengyang, Mengla, Shangyong, Menglun, Mangao) were shown respectively. The key corridors distributed evenly within the scope of Mengyang and Mengla nature reserves, while the key corridors exhibited much more clear structures in the other three reserves. These areas recognized as key corridors at the scale of Xishuangbanna play a critical role in biodiversity protection for sub-reserve management. |
Figure A3 Different scenarios - 5 nodes, 10 nodes, 15 nodes, 20 nodes, 25 nodes and 50 nodes - were shown as the order alphabetic characters (from “a” to “f”). (i) and (ii) represent the first trial and the second trial respectively which were under the same nodes number. The differences among these current density maps can be intuitively compared. |
The authors have declared that no competing interests exist.
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