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Land-use/land-cover change and climate change have changed the spatial–temporal distribution of water resources. The Huai River Basin shows the spatial and temporal changes of climate from 1960 to 2016 and land-use/land-cover changes from 1995 to 2014. Thus, this study aims to investigate climate change, land use, and vegetation evolution in the Upper Huai River Basin. The Mann–Kendall test (MK), Innovative Trend Analysis Method (ITAM), and Sen's slope estimator test were used to detect climate change trends. The land-use/land-cover change was also examined using a transformation matrix and Normalized Difference Vegetation Index (NDVI). The results of this study revealed that precipitation has shown a slightly decreasing trend during the past 56 years. However, the air temperature has increased by 1.2 °C. The artificial and natural vegetation and wetland were decreased by 12,097 km2, 3207 km2, and 641 km2, respectively. On the other hand, resident construction land and artificial water bodies increased by 2277 km2 and 3691 km2, respectively. This indicates that the land cover has significantly changed during the past 30 years. The findings of this study will have implications for predicting the water resources safety and eco-environment of The Huai River Basin. The spatial distribution showed an uneven change in the Huai River Basin. Together, we suggested that the variability of water resources availability in the Huai River Basin was mainly attributed to climate variability, while land use change plays a key role in the sub-basins, which experienced dramatic changes in land use. [ABSTRACT FROM AUTHOR]

The Abbay River Basin, which originates in Ethiopia, is a major tributary and main source of the Nile River Basin. Land cover and vegetation in the Abbay River Basin is highly susceptible to climate change. This study was conducted to investigate the trends of climate change for a period of thirty-six years (1980–2016) within selected stations of the basin by using the innovative trend analysis method, Mann–Kendall test, and Sen's slope estimator test to investigate the mean annual precipitation and temperature variables. Changes in land cover and vegetation in the Abbay River Basin were studied for a period of thirteen years (2001–2013) by using remote sensing, GIS analysis, land cover classification, and vegetation detection methods to assess the land cover and vegetation in the basin. In addition, Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Transformation Matrix were employed to analyze the spatial and temporal patterns of land cover and vegetation impacted by changes in climate. The result reflects that the trend of average annual temperature was remarkably increased (Φ = 0.12, Z = 0.75) in the 36-year period, and the temperature was increased by 0.5°C, although precipitation had slightly decreased during the same period. In the thirteen years' period, forest land and water resource decreased by 3429.62 km2 and 81.45 km2, respectively. In contrast, an increment was observed in grassland (2779.33 km2), cultivated land (535.34 km2), bare land (43.08 km2), urban land (0.65 km2), and wetland (152.66 km2) in the same period. In the study, it was also observed a decrease of an NDVI value by 0.1 was observed in 2013 in the southern part of the basin. The findings of the present study illustrate a significant change in eco-hydrological conditions in the ARB with an adverse impact on the environment. Hydroclimatic changes caused the increase in temperature and decreasing trend in precipitation which significantly impacted the land cover and vegetation in the basin. The changes in land cover were mostly caused by global and local climate influence which mainly affects the hydroclimate and eco-hydrology systems of the basin. The result is consistent with that of the previous studies conducted elsewhere. The findings of this paper could help researchers to understand the eco-hydrological condition of the study basin and become a foundation for further studies. [ABSTRACT FROM AUTHOR]

The upper part of the Huai River basin is spatially extensive, with pronounced environmental gradients driven primarily by precipitation and temperature on broad scales. Therefore, it is an ideal region in which to examine the climate dynamics of the region. This study investigates the annual precipitation and temperature time serious variability, at six designated representative stations, by using the innovative trend analysis method (ITA), Mann-Kendall (MK) and Sen’s slope test estimator. The result showed that the trend of annual precipitation was slightly decreasing in Xiangcheng (Z = -2.04), Zhumadian ( Z= -0.43), Gushi (Z = 0.26), Xinyang (Z = -2.22), and Xichong (Z = -0.59) stations. Increasing trend was observed only in Fuyang station (Z = -0.97). Summer is characterized by high temperature and its major rain season in the study area, which contributes about 49.3% of total rainfall. In all stations the trend of annual temperature in Xiangcheng (Z = 6.72), Zhumadian (Z = 7.04), Gushi (Z = 6.96), Fuyang (Z = 7.07), Xinyang (Z = 7.04) and Xichong (Z = 2.85) sharply increased. The average air temperature has significantly increased by 1.2ºC during the past 56 years. The ITA was found to be reliable and consistent as MK and Sen’s slope test estimators for the study region. Furthermore, ITA can present the data in graphical format for better understanding of the results through detecting a sub trend series. Therefore, this study can be an inordinate resource to other researchers for studying climate variability and their impacts to eco-hydrology using the ITA method. [ABSTRACT FROM AUTHOR]