Meteorological Drought, Hydrological Drought, and NDVI in the Heihe River Basin, Northwest China: Evolution and Propagation

Figure 13

Heat maps showing PC between SDI-1 lagged by 0–6 months and SPI accumulation periods of 1–48 months for different timescales at different periods in the UHRB (Ylx) and MHRB (Zyx). (a) (1965–1979, PC ≥ 0.15 or ≤ ‒0.16, p < 0.05), (b) (1980–2012, PC ≥ 0.14, p<0.01), and (c) (1965–2012, PC ≥ 0.11, p <0.01) in the UHRB (Ylx) and (d) (1965–1984, PC ≥ 0.16 or ≤‒0.11, p < 0.05), (e) (1985–2012, PC ≥ 0.12, p < 0.01), and (f) (1965–2012, PC ≥ 0.10, p < 0.05) in the MHRB (Zyx).

(a)

(b)

(c)

(d)

(e)

(f)