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The present study attempted to investigate the trends of mean annual temperature, precipitation, and streamflow changes to determine their relationships in the upper Huai river basin. The Mann–Kendall (MK), Sen's slope test estimator, and innovative trend detection (ф) (ITA) methods were used to detect the trends. According to the findings, average annual precipitation shows a descending trend (ф = −0.17) in most stations. An increasing trend was found only in Fuyang station (ф = 1.02). In all stations, the trends of mean annual temperature (ф = 0.36) were abruptly increased. During the past 57 years, the mean air temperature has considerably increased by 12°C/10a. The river streamflow showed a dramatic declining trend in all stations for the duration of the study period (1960–2016) (ф = −4.29). The climate variability in the study region affects the quantity of the streamflow. The river streamflow exhibits decreasing trends from 1965 onwards. The main possible reason for the declining stream flow in the study area is the declining amount of precipitation on some specific months due to the occurrence of climate change. The outcomes of this study could create awareness for the policymakers and members of the scientific community, informing them about the hydroclimatic evolutions across the study basin, and become an inordinate resource for advanced scientific research. [ABSTRACT FROM AUTHOR]

Land cover and vegetation in Lake Baikal basin (LBB) are considered to be highly susceptible to climate change. However, there is less information on the change trends in both climate and land cover in LBB and thus less understanding of the watershed sensitivity and adaptability to climate change. Here we identified the spatial and temporal patterns of changes in climate (from 1979 to 2016), land cover, and vegetation (from 2000 to 2010) in the LBB. During the past 40 years, there was a little increase in precipitation while air temperature has increased by 1.4 °C. During the past 10 years, land cover has changed significantly. Herein grassland, water bodies, permanent snow, and ice decreased by 485.40 km2, 161.55 km2 and 2.83 km2, respectively. However, forest and wetland increased by 111.40 km2 and 202.90 km2, respectively. About 83.67 km2 area of water bodies has been converted into the wetland. Also, there was a significant change in Normalized Difference Vegetation Index (NDVI), the NDVI maximum value was 1 in 2000, decreased to 0.9 in 2010. Evidently, it was in the mountainous areas and in the river basin that the vegetation shifted. Our findings have implications for predicting the safety of water resources and water eco-environment in LBB under global change. [ABSTRACT FROM AUTHOR]

Mongolia's Selenga sub-basin of the Lake Baikal basin is spatially extensive, with pronounced environmental gradients driven primarily by precipitation and air temperature on broad scales. Therefore, it is an ideal region to examine the dynamics of the climate and the hydrological system. This study investigated the annual precipitation, air temperature, and river discharge variability at five selected stations of the sub-basin by using Mann-Kendall (MK), Innovative trend analysis method (ITAM), and Sen's slope estimator test. The result showed that the trend of annual precipitation was slightly increasing in Ulaanbaatar (Z = 0.71), Erdenet (Z = 0.13), and Tsetserleg (Z = 0.26) stations. Whereas Murun (Z = 2.45) and Sukhbaatar (Z = 1.06) stations showed a significant increasing trend. And also, the trend of annual air temperature in Ulaanbaatar (Z = 5.88), Erdenet (Z = 3.87), Tsetserleg (Z = 4.38), Murun (Z = 4.77), and Sukhbaatar (Z = 2.85) was sharply increased. The average air temperature has significantly increased by 1.4 °C in the past 38 years. This is very high in the semi-arid zone of central Asia. The river discharge showed a significantly decreasing trend during the study period years. It has been apparent since 1995. The findings of this paper could help researchers to understand the annual variability of precipitation, air temperature, and river discharge over the study region and, therefore, 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]