Spatiotemporal dynamic of environmental indices of watershed sustainability in connection with land-use change

Figures & data

Figure 1. General view, elevation distribution (m), and location of the Shazand Watershed in Markazi Province, Iran.

Table 1. The characteristics of the Landsat image used in the present study

Landsat images	Date	Path/Row	The wavelength of emitted radiance (μm)
Landsat 5 Thematic Mapper (TM)	14. 07. 1986	165/36 165/37	11.45 μm
Landsat 5 Thematic Mapper (TM)	12. 07. 1998
Landsat 7 Enhanced Thematic Mapper Plus (ETM+)	26. 07. 2008
Landsat 8 Operational Land Imager (OLI)	13. 07. 2016		10.895 μm, band 10 12 μm, band 11

Table 2. Land-use distribution (km²) from 1986 to 2016 for the Shazand Watershed, Iran

Node year	Rangeland	Dry farming	Irrigation farming	Orchard	Residential	Outcrops	Bareland	Sparse forest
1986	51.29	31.44	5.13	0.11	1.40	8.10	1.89	0.01
1998	40.37	31.74	12.23	2.61	2.85	8.10	2.09	0.01
2008	39.32	27.70	11.81	5.34	4.88	8.10	2.84	0.01
2016	38.31	25.38	11.81	7.79	5.16	8.10	3.44	0.01

Figure 2. Land-use maps in study years in the Shazand Watershed, Iran.

Table 3. Mean values of study indices of NI, NDWI, NDBI, and LST in node years in the Shazand Watershed, Iran

Year	NDVI	NDWI	NDBI	LST (^◦C)
1986	0.187	0.005	−0.005	38.82
1998	0.176	0.001	−0.001	40.41
2008	0.170	0.002	−0.002	42.21
2016	0.195	0.030	−0.030	38.41

Figure 3. Spatiotemporal distribution of NDVI in study years in the Shazand Watershed, Iran.

Figure 4. Spatiotemporal distribution of NDBI in study years in the Shazand Watershed, Iran.

Figure 5. Spatiotemporal distribution of NDWI in study years in the Shazand Watershed, Iran.

Figure 6. Spatiotemporal distribution of LST (^◦C) in study years in the Shazand Watershed, Iran.

Table 4. Estimated LST (°C) and corresponding ground-based data for study stations in the Shazand Watershed, Iran

Station	Variable	1986	1998	2008	2016
Arak	Measured LST Retrieved LST Difference Accuracy (%)	41.10 37.81 3.29 91.99	43.00 40.19 2.81 93.46	42.60 38.76 3.84 90.98	42.50 39.68 2.82 93.36
Shazand	Measured LST Retrieved LST Difference Accuracy (%)	----	----	----	35.20 31.79 3.41 90.31

Table 5. Relationships between LST and NDVI, NDBI, and NDWI in 1986, 1998, 2008, and 2016 based on 10,000 random points

2016	2008	1998	1986
LST = −18.5NDVI+40.9	LST = −19.3NDVI+41.2	LST = −17.5NDVI+40.8	LST = −18.02NDVI+39.4	NDVI
R^2 = 0.85	R^2 = 0.93	R^2 = 0.89	R^2 = 0.91
LST = 25.0NDBI+39.2	LST = 27.0NDBI+42.3	LST = 26.3NDBI+40.4	LST = 24.0NDBI+38.9	NDBI
R^2 = 0.93	R^2 = 0.92	R^2 = 0.82	R^2 = 0.62
LST = −25.0NDWI+39.2	LST = −27.0NDWI+42.3	LST = −26.3NDWI+40.4	LST = −24.0NDWI+38.9	NDWI
R^2 = 0.93	R^2 = 0.92	R^2 = 0. 82	R^2 = 0. 62

Table 6. LSTs (^◦C) in different land-uses and study years in the Shazand Watershed, Iran

Land-use/cover	1986	1998	2008	2016
Rangeland	39.78	41.09	42.68	39.73
Dry farming	39.68	42.61	44.40	40.19
Irrigation farming	30.55	35.55	39.30	33.11
Orchard	28.25	36.26	41.69	37.14
Outcrops	35.18	37.71	37.89	36.62
Bareland	37.85	40.04	40.45	38.24
Residential	37.20	38.82	41.73	36.83
Sparse forest	40.50	42.48	43.02	39.65

Figure 7. The average rainfall of the stations located in the watershed for the period 1986–2016.

Figure 8. Variations of LST, NDVI, NDBI, and NDWI along with the transect AB (Figure 6, bottom-right) for 2016 in the Shazand Watershed, Iran.

Figure 9. Variations of LST, NDVI, NDBI, and NDWI along the transect CD (Figure 6, bottom-right) for 2016 in the Shazand Watershed, Iran.

Figure 10. Variations of LST, NDVI, NDBI, and NDWI along the transect EF (Figure 6, bottom-right) for 2016 in the Shazand Watershed, Iran.