Impacts of Climate and Land-Use Changes on the Hydrological Processes in the Amur River Basin

Abstract

Under the joint effects resulted from different changes of climate and land-use regimes, spatial-temporal variations of hydrological processes took place in certain principles. Identifying the impact of changes in individual land-use types/climatic factors on hydrological processes is significant for water management and sustainability of watersheds. In this study, seven simulation scenarios were developed using the soil and water assessment tool (SWAT) model to distinguish the impacts of climate and land-use changes on the hydrological processes in the Amur River Basin (ARB) for four periods of 1980–1990, 1991–1999, 2000–2006, and 2007–2013, respectively. Based on the multi-period simulation scenario data, partial least squares regression and ridge regression analyses were performed to further evaluate the effects of changes in individual land-use types/climatic factors on hydrologic components. The results suggested that summer precipitation and summer average temperature were the dominant climatic factors, and crops and wetlands were the principal land-use types contributing to the hydrological responses. In addition, the drastic changes in crop and wetland areas and a clear decline in summer precipitation between the periods of 1991–1999 and 2000–2006 may account for the highest-intensity impacts of climate and land-use changes on the runoff at the outlet (−31.38% and 16.17%, respectively) during the four periods.

Spatial–Temporal Vegetation Dynamics and Their Relationships with Climatic, Anthropogenic, and Hydrological Factors in the Amur River Basin

“…The monthly LAI and FVC values were computed using the maximum value composite (MVC) technique [52], which is widely used in compositing NDVI and other vegetation indexes in order to minimize the interference of atmospheric effects, the scan angle, cloud contamination, and solar zenith angle [29,[53][54][55][56][57]. According to characteristics of climate changes during different periods in the ARB that have described in previous studies [61], in addition to the land use/cover transformations reported in the literature [36,40,62], the entire study period was divided into four periods to analyze the spatial-temporal relationships between environmental factors and vegetation dynamics: 1982-1990 (Period 1), 1991-1999 (Period 2), 2000-2006 (Period 3), and 2007-2013 (Period 4). The detailed information of datasets used in this study as representative of environmental factors are presented in Table 2.To investigate the driving factors of climate on vegetation changes, temperature and precipitation data observed from 1982 to 2013 in 193 meteorological stations within the basin were used.…”

“…The combined datasets of Chinese land use maps with global land use maps from the closest dates in the four historical periods were used as inputs for the GTWR model to investigate the anthropogenic driving factors responsible for regional vegetation changes (urbanization and wetland reclamation, etc.). In addition, the hydrological variables simulated by the SWAT model, as presented in our previous study [61], were adopted to analyze the relationship between hydrological variables and vegetation dynamics. Figure 2 shows an overview of the general workflow followed in this study.…”

The Impact of Reforestation Induced Land Cover Change (1990–2017) on Flood Peak Discharge Using HEC-HMS Hydrological Model and Satellite Observations: A Study in Two Mountain Basins, China

“…Some other studies [12,36] observed the same trend related to the conversion of agricultural land into forest cover and grassland in many mountainous regions of China, including the location of the two studied catchments. The increase in forest coverage is likely attributed to the GTGP and NFCP conservation policies implemented in the late 1990s as a way of reducing soil erosion and floods in many regions in China [15,70].…”

Quantifying the Impact of Future Climate Change on Runoff in the Amur River Basin Using a Distributed Hydrological Model and CMIP6 GCM Projections

“…Precipitation and temperature changes in this basin may have a certain influence on the hydrological process. Zhou et al [9] argued that precipitation and temperature in the summer were the main climatic factors affecting the hydrological processes in this basin. Bolgov et al [10] found that the major floods in the Amur River Basin in 2013 were primarily caused by large areas covered by the extreme precipitation and the long durations of extreme events.…”