Table 6 Number and paper references devoted to various subjects in the selected papers

24

[5, 7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29]

Region, city, village

1

22

[30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50]

Science and technology

2

12

[51,52,53,54,55,56,57,58,59,60,61,62]

Industry

3

11

[63,64,65,66,67,68,69,70,71,72,73]

Economic development

4

9

[74,75,76,77,78,79,80,81,82]

Energy

5

8

[83,84,85,86,87,88,89,90,91]

Environment and climate change

6

4

[92,93,94,95]

Water

7

4

[96,97,98,99]

Terrorism

8

3

[100,101,102]

Food

9

3

[103,104,105,106]

Land use

10

2

[107, 108]

Crisis management

11

9

...

Others

12