Impacts of Climatic Variation and Human Activity on Runoff in Western China

Hydrological cycle is sensitively affected by climatic variation and human activity. Taking the upper- and middle-stream of the Weihe River in western China as an example, using multiple meteorological and hydrological elements, as well as land-use/land-cover change (LUCC) data, we constructed a sensitivity model of runoff to climatic elements and human activities based on the hydro-thermal coupling equilibrium equation, while a cumulative slope was used to establish a comprehensive estimation model for the contributions of climatic variation and human activities to the changes of runoff. The results showed that the above function model established could be well applied to quantitatively study the elasticity of runoff’s response to climatic variation and human activities. It was found that the annual average precipitation, evaporation, wind velocity, sunshine hours, relative humidity and runoff showed decreasing trends and that temperature increased. While in the hydrological cycle, precipitation and relative humidity had a non-linear positive driving effect on runoff, while temperature, evaporation, sunshine hours, wind velocity, and land-use/land-cover change (LUCC) have non-linearly negatively driven the variation of runoff. Moreover, runoff has a strong sensitive response to precipitation, evaporation and LUCC. In areas with strong human activities, the sensitivity of runoff to climatic change was decreasing, and runoff has a greater elastic response to underlying surface parameters. In addition, the analysis showed that the abrupt years of climate and runoff changes in the Weihe River Basin were 1970, 1985 and 1993. Before 1985, the contribution rate of climatic variation to runoff was 68.3%, being greater than that of human activities to runoff, and then the contribution rates of human activities to runoff reached 75.1%. The impact of natural climate on runoff was weakened, and the effect of human activities on runoff reduction increased. Under 30 hypothetical climatic scenarios, the evaluation of runoff in the future showed that the runoff in the Weihe River Basin will be greatly reduced, and the reduction will be more significant during the flood season. Comparing the geographically fragile environments and intense human activities, it was believed that climatic variation had a dramatic effect on driving the water cycle of precipitation and evaporation and affected regional water balance and water distribution, while human activities had driven the hydrological processes of the underlying surface, thus becoming the main factors in the reduction of runoff. This study provided scientific tools for regional climate change and water resources assessment.

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Spatial-Temporal Change of Actual Evapotranspiration and the Causes Based on the Advection–Aridity Model in the Weihe River Basin, China

Water ◽

10.3390/w13030303 ◽

2021 ◽

Vol 13 (3) ◽

pp. 303

Author(s):

Ruirui Xu ◽

Peng Gao ◽

Xingmin Mu ◽

Chaojun Gu

Keyword(s):

Climate Change ◽

Water Resources ◽

Solar Radiation ◽

Vapor Pressure ◽

River Basin ◽

Human Activities ◽

Temporal Change ◽

Hydrological Cycle ◽

Weihe River ◽

Weihe River Basin

Evapotranspiration is a key process between the atmospheric hydrological cycle and the energy cycle, which has a great significance in understanding climate change and the rational use of water resources, especially for the Weihe River basin (WRB) (a basin in China experiencing a shortage of water resources). We investigated the spatial-temporal change of actual evapotranspiration (ETa) based on the daily meteorological variables of 22 meteorological stations and the annual streamflow of three hydrological stations from 1970 to 2018 in the WRB. The contributions of key meteorological variables to ETa changes and the sensitivity coefficient are also quantified. The temporal trends of ETa showed an increasing trend from 1970 to 2018, and the spatial distribution of ETa increased from northwest to southeast in the WRB. Increasing trends were detected in the multi-year average, spring, and winter, but only a few stations passed the significance test. Summer and autumn showed a decreasing trend, but this trend was not significant. Solar radiation is the most sensitive meteorological variable, followed by vapor pressure, wind speed, and mean temperature. Vapor pressure contributes the most to ETa changes, followed by solar radiation. In general, vapor pressure (relative humidity) is the dominant meteorological factor affecting ETa in the WRB. In addition to meteorological factors, the ETa is also affected by combined and complicated factors caused by precipitation and human activities. As an important part of the hydrological cycle, ETa has important research significance for water resources management, economy, agriculture, and ecology and results of this study may be helpful to further clarify the climate change and human activities impacts on the basin hydrological cycle.

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Land Use/Land Cover Change Detection and Urban Sprawl Analysis in the Mount Makiling Forest Reserve Watersheds and Buffer Zone, Philippines

Environments ◽

10.3390/environments6020009 ◽

2019 ◽

Vol 6 (2) ◽

pp. 9

Author(s):

Merlyn Soriano ◽

Noba Hilvano ◽

Ronald Garcia ◽

Aldrin Hao ◽

Aldin Alegre ◽

...

Keyword(s):

Remote Sensing ◽

Land Use ◽

Land Cover ◽

Urban Sprawl ◽

Human Activities ◽

Land Development ◽

Buffer Zone ◽

Land Conversion ◽

Land Use Land Cover ◽

Forest Reserve

Ecologically Valuable Areas play an important role in providing ecosystem services, however, human activities such as land conversion and urban sprawl pose pressures and threats to these areas. The study assessed the land use/land cover and urban sprawl in the Mount Makiling Forest Reserve (MMFR) Watersheds and Buffer Zone from 1992 to 2015 using remote sensing and Geographic Information System (GIS). Results showed that the land use/cover within the MMFR buffer zone has changed from 1992 to 2015 with built-up areas increasing by 117% despite Proclamation 1257, s. 1998 which regulates human activities in the zone. Based on the Shannon entropy analysis the land development in the MMFR buffer zone tends to be dispersed and sprawling. However, when the magnitude of change of urban sprawl in the buffer zone from 2002 to 2015 was calculated, a decrease in the entropy value was observed which implies a compacting pattern as the human settlement in the buffer zone increases over time. Proclamation 1257, s. 1998 needs to be strengthened to protect MMFR and its buffer zone from further encroachment and pressure. Moreover, remote sensing and GIS proved to be useful tools for assessing urban sprawl in ecologically valuable areas such as MMFR.

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Hybrid method for assessing the multi-scale periodic characteristics of the precipitation–runoff relationship: a case study in the Weihe River basin, China

Journal of Water and Climate Change ◽

10.2166/wcc.2016.003 ◽

2016 ◽

Vol 8 (1) ◽

pp. 62-77 ◽

Cited By ~ 6

Author(s):

Aijun Guo ◽

Jianxia Chang ◽

Qiang Huang ◽

Yimin Wang ◽

Dengfeng Liu ◽

...

Keyword(s):

Wavelet Transform ◽

River Basin ◽

Hybrid Method ◽

Hydrological Cycle ◽

Monthly Precipitation ◽

Time Frequency ◽

Multi Scale ◽

Frequency Domains ◽

Weihe River ◽

Weihe River Basin

Fully elucidating the precipitation–runoff relationship (PRR) is of great significance for better water resources planning and management and understanding hydrological cycle processes. For investigating the multi-scale PRR variability in the Weihe River basin in 1960–2010, a new hybrid method is proposed in which ensemble empirical mode decomposition (EEMD) and cross wavelet transform and wavelet transform coherence are used in combination. With the application of mutual information entropy, monthly precipitation and runoff are decomposed into two parts: high- (HFC) and low-frequency components (LFC). The results show that HFCs are characterized by inter- and intra-annual variations in precipitation and runoff, whereas LFCs display approximately two-year periodicity and contain abundant abnormal information of the raw data. Therefore, the PRR between HFCs exhibited significant correlations at the 95% confidence level over the whole time period. However, the correlations of the PRR between LFCs are not significant for many of the time-frequency domains. Additionally, the phase relations are disordered in these time-frequency domains, and no certain trend in phase angle variations can be identified. Through comparative analysis of the anthropogenic activities and climatic events with PRR variations, it can be concluded that the hybrid method can efficiently capture the PRR in various time-frequency domains.

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Multi-criteria potential groundwater contamination and human activities: Araras watershed, Brazil

RBRH ◽

10.1590/2318-0331.0217170052 ◽

2017 ◽

Vol 22 (0) ◽

Cited By ~ 1

Author(s):

Fabíola Geovanna Piga ◽

Nícolas Guerra Rodrigues Tão ◽

Mayara Herrmann Ruggiero ◽

Darlan de Souza Marquezola ◽

Welliton Leandro de Oliveira Boina ◽

...

Keyword(s):

Land Use ◽

Groundwater Contamination ◽

Human Activities ◽

Land Use Land Cover ◽

Surface Water Resources ◽

Contaminant Sources ◽

Potential Groundwater ◽

Water Resources Protection ◽

Clastic Sedimentary ◽

Very High

ABSTRACT Assessment of groundwater contamination potential using geological, hydrological and hydrogeological attributes, is an efficient mechanism of sub-surface water resources protection and conservation. However, usually this method does not take into consideration the potentially polluting human activities, either in punctual or diffuse sources, or because the relative importance of the attributes are not considered. The paper proposes a multi-criteria approach as a way of solving this gap, reducing subjectivity and considering land use/cover due human actions influence in the process. The study was developed in Araras river watershed (Paraná Basin, Brazil) using rock, groundwater, relief, soils, and land use/land cover classification, employing multi-criteria analysis and data of contamination sources. The potential contamination classification showed the predominance (54% of the area) of very high and high potential, especially due to geological environment conditions (exploitation areas and groundwater recharge of the Itararé Aquifer - clastic sedimentary and free flow). The contaminant sources analyzed are located mainly in higher potential contamination areas.

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Quantitative estimation on contributions of climate changes and human activities to decreasing runoff in Weihe River Basin, China

Chinese Geographical Science ◽

10.1007/s11769-015-0734-5 ◽

2015 ◽

Vol 25 (5) ◽

pp. 569-581 ◽

Cited By ~ 7

Author(s):

Shengzhi Huang ◽

Qiang Huang ◽

Yutong Chen

Keyword(s):

River Basin ◽

Human Activities ◽

Climate Changes ◽

Quantitative Estimation ◽

Weihe River ◽

Weihe River Basin

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Variations in the precipitation–runoff relationship of the Weihe River Basin

Hydrology Research ◽

10.2166/nh.2016.032 ◽

2016 ◽

Vol 48 (1) ◽

pp. 295-310 ◽

Cited By ~ 13

Author(s):

Aijun Guo ◽

Jianxia Chang ◽

Dengfeng Liu ◽

Yimin Wang ◽

Qiang Huang ◽

...

Keyword(s):

River Basin ◽

Human Activities ◽

Driving Forces ◽

Potential Evapotranspiration ◽

Annual Runoff ◽

Change Points ◽

Archimedean Copulas ◽

Significance Level ◽

Weihe River ◽

Weihe River Basin

The main goal of this study is to introduce the Archimedean copulas, which overcome the low accuracy and subjective nature of the traditional double mass curve method, to investigate the precipitation–runoff relationship (PRR) and detect change points in the Weihe River Basin (WRB). With the construction of a joint distribution between precipitation and runoff by the Archimedean copulas, a statistical variable considering the distribution parameter was estimated to judge the change point of the PRR. The results show that: (1) annual precipitation and runoff present decreasing trends that are significant and insignificant, respectively, at the 95% significance level, while annual potential evapotranspiration (PET) increases slightly; (2) change points of the PRR occurred in 1971 and 1994; (3) the annual runoff changed more dramatically than precipitation during the periods from 1972 to 1994 and 1995 to 2010 compared with 1960–1971, which indicates that in addition to precipitation, there are some other non-precipitation factors that are responsible for the change in the PRR; and (4) the contributions to runoff from human activities declined from 1972 to 1994 (84.15%) and 1995 to 2010 (57.16%). These results suggest that human activities (e.g., irrigation, reservoirs, water-and-soil conservation) were the primary driving forces leading to changes in the PRR in the WRB.

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Comparative assessment of extreme climate variability and human activities on regional hydrologic droughts in the Weihe River basin, North China

Proceedings of the International Association of Hydrological Sciences ◽

10.5194/piahs-369-141-2015 ◽

2015 ◽

Vol 369 ◽

pp. 141-146

Author(s):

H. Shen ◽

L. Ren ◽

F. Yuan ◽

X. Yang

Keyword(s):

River Basin ◽

Human Activity ◽

Human Activities ◽

Climate Extremes ◽

Hydrologic Model ◽

Climate Indices ◽

Extreme Climate ◽

Runoff Series ◽

Weihe River ◽

Weihe River Basin

Abstract. Drought is a comprehensive phenomenon not only resulting from precipitation deficits and climatic factors, but also being related to terrestrial hydrologic conditions and human activities. This paper investigated the relationships among regional hydrologic drought, climate extremes and human activities in the Weihe River basin, northwest China, where is also called Guanzhong Plain. First, the study period was divided into baseline and variation period according to the runoff trend analysis. Subsequently, the variable infiltration capacity (VIC) macroscale distributed hydrologic model was applied to reconstruct the natural runoff series in variation period. Furthermore, the effects of climate change and human activities on runoff were separated by the modelling results. Finally, standardized runoff index (SRI) and extreme climate indices were generated to quantatively assess the relationships among hydrologic droughts, climate extremes and human activity impacts. The results indicated that human activity impacts is a remarkable source of runoff reduction and represented an in-phase pattern of SRI-based drought severity and warm days. It also showed that the SRI-based floods and droughts characteristics are in good correlation with extreme precipitation.

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Water Sensitive Urban Planning

Earth & Environmental Science Research & Reviews ◽

10.33140/eesrr.03.01.05 ◽

2020 ◽

Vol 3 (1) ◽

Keyword(s):

Land Use ◽

Surface Water ◽

Urban Planning ◽

Land Cover ◽

Urban Areas ◽

Hydrological Cycle ◽

Water Cycle ◽

Water Runoff ◽

Land Use Land Cover ◽

Open Spaces

Extreme weather events responding to imbalances in natural and physical environment systems have been observed recently with floods, droughts, tsunamis etc, mostly in the urban areas of the world. Several studies carried out have modelled surface water runoff from land use and land cover with differential precipitation and found that surface runoff increases with the proportion of built up areas. Despite these facts, some urban catchments still reveal a better natural water cycle though built up is more in them as compared to others having less built up but facing disturbed natural hydrological cycle. Considering this, hypothesis can be made that only built up is not responsible for the runoff generation but some other factor like open spaces, planning, geology plays an important role in the behavior of runoff. The paper attempts to correlate land use, land cover, built up and resulting runoff for urban watersheds. It also finds out correlation between local bye laws and behavior of water cycle over it. Considering runoff modification as prime effect of urbanization to the hydrological cycle in terms of behavior of surface water, the intention of the study is to contribute to a better understanding of the relation of the local hydrological parameters in urban areas to the physical transformation of land covers as impervious built ups and develop an understanding of the resulting effects of components of one system on other. This will help to predict and project the changes in hydrological cycles due to land use /land cover transformation and thus help urban planners in physical planning of new urban areas as well as development of an existing urban area to achieve a maximum sustainability in the city. Hence, water sensitive urban planning with combination of built up, open spaces and geology will help planners to cope with the unwanted increase in runoff leading to flash floods. For this purpose, 19 urban water catchments were studied for their development scenario byelaws, built up, runoff and water tables for past 30 years and above. Observations were used to correlate urban parameters like land cover, runoff, infiltration, and evaporation with hydrological ones and bring a model solution for balanced water cycle achievement during urbanization.

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