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Changes in potential evapotranspiration and surface runoff in 1981–2010 and the driving factors in Upper Heihe River Basin in Northwest China 
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下载免费PDF全文 Changes in potential evapotranspiration and surface runoff can have profound implications for hydrological processes in arid and semiarid regions. In this study, we investigated the response of hydrological processes to climate change in Upper Heihe River Basin in Northwest China for the period from 1981 to 2010. We used agronomic, climatic and hydrological data to drive the Soil and Water Assessment Tool model for changes in potential evapotranspiration (ET0) and surface runoff and the driving factors in the study area. The results showed that increasing autumn temperature increased snow melt, resulting in increased surface runoff, especially in September and October. The spatial distribution of annual runoff was different from that of seasonal runoff, with the highest runoff in Yeniugou River, followed by Babaohe River and then the tributaries in the northern of the basin. There was no evaporation paradox at annual and seasonal time scales, and annual ET0 was driven mainly by wind speed. ET0 was driven by relative humidity in spring, sunshine hour duration in autumn and both sunshine hour duration and relative humility in summer. Surface runoff was controlled by temperature in spring and winter and by precipitation in summer (flood season). Although surface runoff increased in autumn with increasing temperature, it depended on rainfall in September and on temperature in October and November. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Precipitation runoff is a critical hillslope hydrological process for downslope streamflow and piedmont/floodplain recharge. Shimen hillslope micro‐catchment is strategically located in the central foothill region of Taihang Mountains, where runoff is crucial for water availability in the piedmont corridors and floodplains of north China. This study analyzes precipitation‐runoff processes in the Shimen hillslope micro‐catchment for 2006–2008 using locally designed runoff collection systems. The study shows that slope length is a critical factor, next only to precipitation, in terms of runoff yield. Regression analysis also shows that runoff is related positively to precipitation, and negatively to slope length. Soil mantle in the study area is generally thin and is therefore not as critical a runoff factor as slope length. The study shows a significant difference between overland and subsurface runoff. However, that between the 0–10 and 10–20 cm subsurfaces is insignificant. Runoff hardly occurs under light rains (<10 mm), but is clearly noticeable under moderate‐to‐rainstorm events. In the hillslope catchment, vertical infiltration (accounting for 42–84% of the precipitation) dominates runoff processes in subsurface soils and weathered granite gneiss bedrock. A weak lateral flow (at even the soil/bedrock interface) and the generally small runoff suggest strong infiltration loss via deep percolation. This is critical for groundwater recharge in the downslope piedmont corridors and floodplains. This may enhance water availability, ease water shortage, avert further environmental degradation, and reduce the risk of drought/flood in the event of extreme weather conditions in the catchment and the wider north China Plain. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Juana P Moiwo 《东北亚地学研究》2006,9(1):80-93
IntroductionNever before hasit beensotrue than now,thatlandis ali mitedresource.Population growth and as-sociated human activities,especially agricultureacross the world have not only led to land degrada-tion,but soil loss at rates that have pushed arablesoils to frontier thresholds.In the absence of arablesoil,the human environment would cease to groworeven demise(Ramet al.,2006).Studies haveshownthat in many regions of the world,runoff andsoil erosion differ withland-use type.Judson(1965)re… 相似文献
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全球变化下地表反照率研究进展 总被引：12，自引：0，他引：12
地表反照率表征地球表面对太阳辐射的反射能力,决定着地表与大气之间辐射能量的分配过程,是影响地球气候系统的关键变量。在全球变化日益突出的今天,地表反照率与全球变化的相互影响机制已经成为地球科学研究领域的热点问题之一。地表反照率的细微变化,会影响到地气系统的能量收支平衡,进而引起区域以至全球气候变化。详细介绍地表反照率影响... 相似文献
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Water storage depletion is an increasing hydrological threat to agricultural production and social stability across the globe. It is fast approaching threshold levels especially in arid/semiarid regions with low precipitation and excessive evapotranspiration (ET). This study analyses water storage dynamics in the North China Region (NCR) – an important grain‐production base in China. It uses monthly Gravity Recovery and Climate Experiment (GRACE), Global Land Data Assimilation System (GLDAS) and field‐measured precipitation data products for 2002–2009. The datasets are analysed in a basin‐scale water balance equation to determine the state of storage in the NCR study area. Based on the validated satellite‐based data products with field‐measured values, average error/bias in the datasets is <10%. The analysis also shows favourable agreements among the GRACE‐derived and flux‐based storage changes at various temporal scales. Whereas the amplitudes and phases of the precipitation and ET fluxes are largely stable for 2002–2009, those of GLDAS runoff and GRACE total water storage anomaly apparently narrow out. The linear trends in the monthly, seasonal and annual storage changes are negative for the study period, suggesting storage loss. There is an apparent seasonality of storage change in the study area; with summer storage gain, winter storage loss and an overall storage loss that is on the average of 16.8 mm/yr. Storage loss is most severe in the central floodplain region (the main irrigated production zone) of the study area. Storage depletion in this important agro‐based semi‐arid region could have negative implications for the millions of people in the region and beyond in terms of water supply, crop production, food security and social stability. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Dr Juana Paul Moiwo Prof Yonghui Yang Shumin Han Wenxi Lu Nana Yan Bingfang Wu 《水文研究》2011,25(14):2275-2287
Soil moisture is a consideration for soil conservation, agricultural production and climate modelling. This article presents a simple method for estimating soil moisture storage under water stress and storage depletion conditions. The method is driven by the common agro‐hydrologic variables of precipitation (PPT), irrigation (IRR) and evapotranspiration (ET). The proposed method is successfully tested for the 152 000 km2 floodplain region of Hai River Basin using 48 consecutive months (2003–2006) of data. Soil moisture data from global land data assimilation system/Noah land surface model are validated with ground‐truth data from 102 soil moisture monitoring sites. The validated soil moisture is used in combination with in situ groundwater data to quantify total water storage change (TWSC) in the region. The estimated storage change is in turn compared with gravity recovery and climate experiment‐derived TWSC for the study area. The soil moisture and TWSC terms show favourable agreements, with discrepancies of < 10% on the average. While there is no consistent seasonal trend in soil moisture, TWSC shows a strong seasonality. It is low in spring and high in summer. This trend corresponds with the IRR–PPT season in the study area. Change in groundwater and total water storage indicates storage depletion in the basin. Storage depletion in the region is driven mainly by groundwater IRR and ET loss. Despite the low PPT and high ET, there is narrowing seasonal trend in soil moisture. This is achieved at the expense of groundwater storage. IRR pumping has induced extensive groundwater depletion in the basin. It is therefore vital to develop cultivation strategies that aim at limiting IRR pumping and ET loss. Water management practices that not only reduce waste but also ensure high productivity and ecological sustainability could also mitigate storage depletion in the region. These measures could reduce further not only the seasonal trend in soil moisture but also that in groundwater storage. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Moiwo Juana Paul 《中国地理科学(英文版)》2006,16(3):229-235
The impact of land-use on distributed groundwater recharge and discharge in the western Jilin (WJ) was analyzed in this study.
WJ is a transitional, semi-arid zone with a fragile, hydrological closed ecosystem in the Songhua River Basin (SRB). The research
tool includes a seamlessly linked MODFLOW, WetSpass, the Seepage packages, and ArcGIS. The model calibration showed good agreement
between simulated water table elevation and measured water table depths, while predicted groundwater discharge zones showed
strong correlations with field occurrences of drainage systems and wetlands. Simulated averages for distributed recharge,
water table elevation and groundwater drawdown were 377.42mm/yr, 194.43m, and 0.18m respectively. Forest vegetation showed
the highest recharge, followed by agricultural farmlands, while open-water and other drainage systems constituted groundwater
exit zones. When present land-use conditions were compared with the hypothetical natural pre-development scenario, an overall
loss of groundwater recharge (24.09mm/yr) was observed, which for the project area is 18.05 × 108m3. Groundwater abstraction seemed to be the cause of water table drawdown, especially in the immediate vicinities of the supply
wells. An important issue of the findings was the ability of the hypothetical forest vegetation to protect, and hence sustain
aquifer reserves and dependent ecosystems. The profound data capture capability of ArcGIS makes it particularly useful in
spatio-temporal hydroecological modeling.
Biography: Moiwo Juana PAUL (1967–), male, a native of Sierra Leone of West Africa, Ph.D. candidate, specialized in wetland
ecology. 相似文献
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