APPLICABILITY OF THE DEVELOPED METHODOLOGY

Super User Blog 24 September 2019 Hits: 1146

The derived methodology on assessing land desertification risk using indicators can be applied in (a) croplands, (b) grazing lands, and (c) forested areas.

In these land uses, the land degradation processes or causes that have been considered in the proposed methodology are: i) Soil erosion by water or tillage, ii) Soil salinization, iii) Water stress, iv) Overgrazing and v) Forest fires. The most important indicators for each land use and land degradation process are shown in Table 1, while Table 2, shows the list of important indicators defined for each land degradation process.

Table 1. Number of candidate indicators used for the analysis and number of effective indicators for each process or cause of land degradation and desertification

a/a	Degradation process	Major land use	Number of candidate indicators	Number of effective indicators
1	Soil erosion by water runoff	Agriculture	49	17
		Pastures and shrubland	49	15
		Forests	49	11
2	Tillage erosion	Agriculture	16	10
3	Soil salinization	Agriculture, natural vegetation	27	9
4	Water stress	Agriculture, natural vegetation	50	12
5	Overgrazing	Natural vegetation, agriculture	44	16
6	Forest fires	Natural vegetation	29	8

Table 2. Important indicators affecting the various processes or causes of land degradation and desertification (symbol • means important indicator)

A/A	Indicators	Land degradation process or cause
		Water erosion			Tillage erosion	Soil salinization		Water stress	Over-grazing	Forest fires
		Cropland	Pastures	Forests	Tillage erosion	Soil salinization		Water stress	Over-grazing	Forest fires
		Indicators related to physical environment
1	Annual rainfall	¨
2	Potential evapotranspiration					¨
3	Aridity index			¨					¨
4	Rainfall seasonality	¨	¨	¨				¨	¨	¨
5	Rainfall erosivity								¨
6	Water quality					¨
7	Water scarcity							¨
8	Flooding frequency					¨
9	Soil drainage					¨			¨
10	Parent material				¨
11	Slope aspect	¨
12	Slope gradient	¨			¨			¨
13	Soil texture		¨
14	Soil depth	¨	¨	¨
15	Organic matter surface horizon	¨			¨
16	Exposure of rock outcrops								¨
17	Fire risk			¨
18	Distance from seashore					¨
		Indicators related to socio-economics
19	Farm size								¨
20	Farm ownership					¨
21	Land fragmentation								¨	¨
22	Population density			¨		¨	¨
23	Old age index									¨
24	Population growth rate									¨
25	Tourism intensity		¨
26	Tourism change						¨
27	Parallel employment	¨
28	Farm subsidies	¨	¨
		Indicators related to land management
29	Major land use				¨					¨
30	Vegetation cover type	¨		¨
31	Plant cover	¨	¨	¨					¨
32	Land use period		¨						¨
33	Land use intensity	¨	¨		¨					¨
34	Mechanization index				¨
35	Tillage operations	¨			¨
36	Tillage direction		¨
37	Tillage depth		¨		¨
38	Grazing control		¨						¨	¨
39	Grazing intensity			¨					¨
40	Deforested area						¨
41	Fire frequency						¨		¨
42	Burned area		¨	¨					¨
43	Fire protection			¨					¨	¨
44	Sustainable farming	¨
45	Soil erosion control						¨		¨
46	Soil water conservation		¨
47	% irrigation of arable land					¨
48	Groundwater exploitation					¨	¨
49	Runoff water storage	¨	¨
50	Terracing	¨			¨
51	Land abandonment	¨		¨			¨		¨
52	Policy implementation	¨	¨		¨		¨
53	Impervious surface area						¨