This page has only limited features, please log in for full access.
Multi-time scale surface water extent (SWE) dynamics are very important to understand climate change impacts on water resources. With Landsat 5/7/8 images and Google Earth Engine (GEE), an improved threshold-based water extraction algorithm and a novel surface water gaps (SWGs) interpolation method based on historical water frequency were applied to build surface water area (SWA, namely SWE without ice) and water body area (WBA, namely SWE with ice) monthly (January 2001–December 2019) and annual (1986–2019) time series in the upper reaches of the Yellow River (UYR). The Mann-Kendall test was used to analyse SWE trends, and the ridge regression was performed to figure out the relative contributions of meteorological factors to SWE dynamics. The pixels with modified normalized difference water index (MNDWI) higher than normalized difference vegetation index (NDVI) or enhanced vegetation index (EVI) were identified as SWE. The mean relative error (MRE) of the SWGs interpolation results was below 10%. At the annual scale, the average SWA and number of lakes over 1 ha showed significant upward trends of 4.4 km2 yr−1 and 7.53 yr−1, respectively. The monthly WBA increased in summer and autumn while decreased in spring and winter. The maximum freezing and thawing ratios were 53.74% in December and 37.32% in May, respectively. Attribution analysis showed that precipitation and wind speed were the foremost factors dominating the dynamics of annual SWA and monthly WBA, respectively. Our findings confirmed that climatic changes have altered the dynamics of water bodies in the UYR.
Haowei Zhou; Suxia Liu; Shi Hu; Xingguo Mo. Retrieving dynamics of the surface water extent in the upper reach of Yellow River. Science of The Total Environment 2021, 800, 149348 .
AMA StyleHaowei Zhou, Suxia Liu, Shi Hu, Xingguo Mo. Retrieving dynamics of the surface water extent in the upper reach of Yellow River. Science of The Total Environment. 2021; 800 ():149348.
Chicago/Turabian StyleHaowei Zhou; Suxia Liu; Shi Hu; Xingguo Mo. 2021. "Retrieving dynamics of the surface water extent in the upper reach of Yellow River." Science of The Total Environment 800, no. : 149348.
Accurately simulating the soil nitrogen (N) cycle is crucial for assessing food security and resource utilization efficiency. The accuracy of model predictions relies heavily on model parameterization. The sensitivity and uncertainty of the simulations of soil N cycle of winter wheat-summer maize rotation system in the North China Plain (NCP) to the parameters were analyzed. First, the N module in the Vegetation Interface Processes (VIP) model was expanded to capture the dynamics of soil N cycle calibrated with field measurements in three ecological stations from 2000 to 2015. Second, the Morris and Sobol′ algorithms were adopted to identify the sensitive parameters that impact soil nitrate stock, denitrification rate, and ammonia volatilization rate. Finally, the shuffled complex evolution developed at the University of Arizona (SCE-UA) algorithm was used to optimize the selected sensitive parameters to improve prediction accuracy. The results showed that the sensitive parameters related to soil nitrate stock included the potential nitrification rate, Michaelis constant, microbial C/N ratio, and slow humus C/N ratio, the sensitive parameters related to denitrification rate were the potential denitrification rate, Michaelis constant, and N2 O production rate, and the sensitive parameters related to ammonia volatilization rate included the coefficient of ammonia volatilization exchange and potential nitrification rate. Based on the optimized parameters, prediction efficiency was notably increased with the highest coefficient of determination being approximately 0.8. Moreover, the average relative interval length at the 95% confidence level for soil nitrate stock, denitrification rate, and ammonia volatilization rate were 11.92, 0.008, and 4.26, respectively, and the percentages of coverage of the measured values in the 95% confidence interval were 68%, 86%, and 92%, respectively. By identifying sensitive parameters related to soil N, the expanded VIP model optimized by the SCE-UA algorithm can effectively simulate the dynamics of soil nitrate stock, denitrification rate, and ammonia volatilization rate in the NCP.
Lihong He; Xingguo Mo; Shi Hu; Suxia Liu. Global sensitivity and uncertainty analysis of the VIP ecosystem model with an expanded soil nitrogen module for winter wheat-summer maize rotation system in the North China Plain. Pedosphere 2021, 31, 822 -838.
AMA StyleLihong He, Xingguo Mo, Shi Hu, Suxia Liu. Global sensitivity and uncertainty analysis of the VIP ecosystem model with an expanded soil nitrogen module for winter wheat-summer maize rotation system in the North China Plain. Pedosphere. 2021; 31 (5):822-838.
Chicago/Turabian StyleLihong He; Xingguo Mo; Shi Hu; Suxia Liu. 2021. "Global sensitivity and uncertainty analysis of the VIP ecosystem model with an expanded soil nitrogen module for winter wheat-summer maize rotation system in the North China Plain." Pedosphere 31, no. 5: 822-838.
Degradation of grassland over the Tibetan Plateau (TP) has become increasingly intense, producing a wide impact on the local and downstream environment and society. There is a pressing demand to explore contributions of climate change or human activity. Based on the simulations at 1-km spatial resolution during 2001–2017 from the VIP distributed eco-hydrological model, the trends of grass growth (expressed as gross primary productivity (GPP)), water consumption (expressed as evapotranspiration (ET)), and water use efficiency (WUE) were studied to identify the drivers by using the ridge regressions. The results show that 18.75% and 12.43% of grassland showed upward and downward ET trends, respectively. Elevated atmospheric CO2 concentration (eCO2), increasing precipitation (PRE), leaf area index (LAI), and wind speed (U) collectively dominated the uptrend of ET, and their contributions were 62%, 17%, 9%, and 9%, respectively. eCO2 and the diminished PRE and LAI were the principal causes of the decrease of ET. Their contributions were −42%, −9% and −7%, respectively. 81.13% of the grassland showed an uptrend in GPP, while only 0.04% showed downward tendencies. Rising air temperature (Ta) and eCO2 have jointly promoted GPP, with their contributions being 36% and 58%, respectively. The water vapor pressure (EA), U, and PRE reduction and warmer Ta caused a decrease in GPP, and their contributions were −25%, −23%, −9%, and −25%, respectively. 36.60% of the grassland showed a positive WUE trend, while only 3.98% showed a downtrend. The contribution of human activities is relatively small compared to that of climate change. Clarifying the contributions to ET, GPP, and WUE in grassland will support the policy-making for ecological management and environmental protection over the plateau.
Wen Liu; Xingguo Mo; Suxia Liu; Zhonghui Lin; Changhe Lv. Attributing the changes of grass growth, water consumed and water use efficiency over the Tibetan Plateau. Journal of Hydrology 2021, 598, 126464 .
AMA StyleWen Liu, Xingguo Mo, Suxia Liu, Zhonghui Lin, Changhe Lv. Attributing the changes of grass growth, water consumed and water use efficiency over the Tibetan Plateau. Journal of Hydrology. 2021; 598 ():126464.
Chicago/Turabian StyleWen Liu; Xingguo Mo; Suxia Liu; Zhonghui Lin; Changhe Lv. 2021. "Attributing the changes of grass growth, water consumed and water use efficiency over the Tibetan Plateau." Journal of Hydrology 598, no. : 126464.
Secular polar drift underwent a directional change in the 1990s, but the underlying mechanism remains unclear. In this study, polar motion observations are compared with geophysical excitations from the atmosphere, oceans, solid Earth, and terrestrial water storage (TWS) during the period of 1981‐2020 to determine major drivers. When contributions from the atmosphere, oceans, and solid Earth are removed, the residual dominates the change in the 1990s. The contribution of TWS to the residual is quantified by comparing the hydrological excitations from modeled TWS changes in two different scenarios. One scenario assumes that the TWS change is stationary over the entire study period, and another scenario corrects the stationary result with actual glacier mass change. The accelerated ice melting over major glacial areas drives the polar drift towards 26° E for 3.28 mas/yr after the 1990s. The findings offer a clue for studying past climate‐driven polar motion.
S. Deng; S. Liu; X. Mo; L. Jiang; P. Bauer‐Gottwein. Polar Drift in the 1990s Explained by Terrestrial Water Storage Changes. Geophysical Research Letters 2021, 48, 1 .
AMA StyleS. Deng, S. Liu, X. Mo, L. Jiang, P. Bauer‐Gottwein. Polar Drift in the 1990s Explained by Terrestrial Water Storage Changes. Geophysical Research Letters. 2021; 48 (7):1.
Chicago/Turabian StyleS. Deng; S. Liu; X. Mo; L. Jiang; P. Bauer‐Gottwein. 2021. "Polar Drift in the 1990s Explained by Terrestrial Water Storage Changes." Geophysical Research Letters 48, no. 7: 1.
Studies of evapotranspiration on remote tropical coral islands are important to explore and sustain scarce freshwater resources. However, there is a significant knowledge gap between research to evaluate evapotranspiration based on remote sensing methods and the influences of different land use types on water dynamics on reclaimed coral islands. This study applied the remote-sensing-based Vegetation Interfaces Processes (VIP-RS) model to estimate actual evapotranspiration (ETa ) on Zhaoshu Island, Yongxing Island, and Yongshu Island in the South China Sea from 2016 to 2019. The results showed that the average annual ETa of Zhaoshu Island, Yongxing Island, and Yongshu Island was 685 mm, 530 mm, and 210 mm, respectively. Annual transpiration (Ec ) and soil evaporation (Es ) exhibited similar patterns on the natural islands; however, Es controlled the water consumption on the reclaimed islands. Water dynamics exhibited seasonal fluctuations due to the uneven distribution of precipitation (PRP). However, ETa of the natural islands was higher than PRP in the dry season, indicating vegetation has to absorb water from the groundwater to sustain growth. The results also agreed with the analysis of dominant driving factors based on partial correlation analysis, which demonstrated that the Normalized Difference Vegetation Index (NDVI) is the most important factor that influences ETa , while relative humidity (RH) controlled the bare land or sparsely vegetated areas on the reclaimed islands. The setting of different land use types showed that vegetation and built-up or hardened roads took control of evapotranspiration and rainwater collection, respectively, which play important roles in water dynamics on corals islands. The evaluation of ETa based on a remote-sensing-based model overcame the difficulty in fieldwork observation, which improves the certainty and accuracy at a spatial scale. In addition, it gave us a new reference to protect and manage scarce freshwater resources properly.
Shengsheng Han; Suxia Liu; Shi Hu; Xianfang Song; Xingguo Mo. Evapotranspiration on Natural and Reclaimed Coral Islands in the South China Sea. Remote Sensing 2021, 13, 1110 .
AMA StyleShengsheng Han, Suxia Liu, Shi Hu, Xianfang Song, Xingguo Mo. Evapotranspiration on Natural and Reclaimed Coral Islands in the South China Sea. Remote Sensing. 2021; 13 (6):1110.
Chicago/Turabian StyleShengsheng Han; Suxia Liu; Shi Hu; Xianfang Song; Xingguo Mo. 2021. "Evapotranspiration on Natural and Reclaimed Coral Islands in the South China Sea." Remote Sensing 13, no. 6: 1110.
The Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) produces high-resolution precipitation estimates and serves as an invaluable data source for data-scarce and ungauged basins. This study comprehensively evaluates two near-real time products (IMERG-E and IMERG-L) and a post-real time dataset (IMERG-F) of IMERG V06B from 2014 to 2019 on basin and grid scales in the Yellow River source region, a data-sparse basin in the northeastern Tibetan Plateau. Results show that the three IMERG products can well depict the spatial distribution of precipitation in the study area. Compared with IMERG-E and IMERG-L, the gauge-adjusted IMERG-F shows better agreement and event detection on both basin and grid scale, yet is limited in improving data accuracy. The near-real time products, IMERG-E and IMERG-L, underestimate precipitation across the basin (~−37.82% and ~−38.55%, respectively). At the same time, post-real time product exhibits negative errors in drier areas and positive errors in wetter regions that are roughly separated by the basin's 3900 m contour. The correlation, error metrics, and detecting ability of the three products upgrade from northwest to southeast as the climate becomes wet. Temporal properties exhibit dependence on meteorological conditions. Specifically, the performance in the wet season is superior to that in the dry season. For instance, the normalized root mean square error for IMERG-F was reduced by 55.10% from dry season to wet season. IMERG products' capability to detect precipitation is affected by temporal scale, intensity, and phase. The reliability of these satellite precipitation products increases when the time interval extends from daily to monthly. IMERG can better estimate moderate precipitation, especially in the range of 5–10 mm/d. The products generally perform worse for solid precipitation than for liquid one. However, interactions of precipitation phases and intensities lead to a decrease in accuracy for light precipitation (<5 mm/d) but an increase for moderate events (≥5 mm/d) when the phase transforms from solid to liquid. Uncertainty of reference data results in an underestimation of product quality. These findings provide a useful reference for the application of IMERG products in cold mountainous areas and reveal the needs for an exhaustive calibration, especially for solid precipitation.
Chengcheng Meng; Xingguo Mo; Suxia Liu; Shi Hu. Extensive evaluation of IMERG precipitation for both liquid and solid in Yellow River source region. Atmospheric Research 2021, 256, 105570 .
AMA StyleChengcheng Meng, Xingguo Mo, Suxia Liu, Shi Hu. Extensive evaluation of IMERG precipitation for both liquid and solid in Yellow River source region. Atmospheric Research. 2021; 256 ():105570.
Chicago/Turabian StyleChengcheng Meng; Xingguo Mo; Suxia Liu; Shi Hu. 2021. "Extensive evaluation of IMERG precipitation for both liquid and solid in Yellow River source region." Atmospheric Research 256, no. : 105570.
Using the Global Land Surface Satellite (GLASS) leaf area index (LAI), the actual evapotranspiration (ETa) and available water resources in the Mekong River Basin were estimated with the Remote Sensing-Based Vegetation Interface Processes Model (VIP-RS). The relative contributions of climate variables and vegetation greening to ETa were estimated with numerical experiments. The results show that the average ETa in the entire basin increased at a rate of 1.16 mm year−2 from 1980 to 2012 (36.7% of the area met the 95% significance level). Vegetation greening contributed 54.1% of the annual ETa trend, slightly higher than that of climate change. The contributions of air temperature, precipitation and the LAI were positive, whereas contributions of solar radiation and vapor pressure were negative. The effects of water supply and energy availability were equivalent on the variation of ETa throughout most of the basin, except the upper reach and downstream Mekong Delta. In the upper reach, climate warming played a critical role in the ETa variability, while the warming effect was offset by reduced solar radiation in the Mekong Delta (an energy-limited region). For the entire basin, the available water resources showed an increasing trend due to intensified precipitation; however, in downstream areas, additional pressure on available water resources is exerted due to cropland expansion with enhanced agricultural water consumption. The results provide scientific basis for practices of integrated catchment management and water resources allocation.
Shi Hu; Xingguo Mo. Attribution of Long-Term Evapotranspiration Trends in the Mekong River Basin with a Remote Sensing-Based Process Model. Remote Sensing 2021, 13, 303 .
AMA StyleShi Hu, Xingguo Mo. Attribution of Long-Term Evapotranspiration Trends in the Mekong River Basin with a Remote Sensing-Based Process Model. Remote Sensing. 2021; 13 (2):303.
Chicago/Turabian StyleShi Hu; Xingguo Mo. 2021. "Attribution of Long-Term Evapotranspiration Trends in the Mekong River Basin with a Remote Sensing-Based Process Model." Remote Sensing 13, no. 2: 303.
With the developments of population and economy, it is necessary to assess the increasing impacts of human activities on evapotranspiration (ET) for sustainable water resources management. The discrepancies between the GRACE-based ET (ETGRACE) by water balance method and the simulated ET (ETVIP) using VIP-RS (Remote Sensing based Vegetation Interface Processes) model were applied to quantify the human-induced ET (HET) in the Ziya-Daqing Basins (ZDB) and Gangnan Reservoir Basin (GRB) in the period 2006–2015. It was found that uncertainty of ET GRACE mainly came from terrestrial water storage changes; ET VIP was noticeably lower than ET GRACE by 13.5% and 18.5% in the ZDB and GRB, respectively; and HET had increased significantly in September, since 2013 and 2014 in the ZDB and GRB, respectively. The increase of HET in the ZDB was attributed to the increases in GDP and domestic water consumption, while that in the GRB was caused by the increases in groundwater resources.
Yi Liu; Xingguo Mo; Shi Hu; Xuejuan Chen; Suxia Liu. Assessment of human-induced evapotranspiration with GRACE satellites in the Ziya-Daqing Basins, China. Hydrological Sciences Journal 2020, 65, 2577 -2589.
AMA StyleYi Liu, Xingguo Mo, Shi Hu, Xuejuan Chen, Suxia Liu. Assessment of human-induced evapotranspiration with GRACE satellites in the Ziya-Daqing Basins, China. Hydrological Sciences Journal. 2020; 65 (15):2577-2589.
Chicago/Turabian StyleYi Liu; Xingguo Mo; Shi Hu; Xuejuan Chen; Suxia Liu. 2020. "Assessment of human-induced evapotranspiration with GRACE satellites in the Ziya-Daqing Basins, China." Hydrological Sciences Journal 65, no. 15: 2577-2589.
During water stress, crops undertake adjustments in functional, structural, and biochemical traits. Hyperspectral data and machine learning techniques (PLS-R) can be used to assess water stress responses in plant physiology. In this study, we investigated the potential of hyperspectral optical (VNIR) measurements supplemented with thermal remote sensing and canopy height (hc) to detect changes in leaf physiology of soybean (C3) and maize (C4) plants under three levels of soil moisture in controlled environmental conditions. We measured canopy evapotranspiration (ET), leaf transpiration (Tr), leaf stomatal conductance (gs), leaf photosynthesis (A), leaf chlorophyll content and morphological properties (hc and LAI), as well as vegetation cover reflectance and radiometric temperature (TL,Rad). Our results showed that water stress caused significant ET decreases in both crops. This reduction was linked to tighter stomatal control for soybean plants, whereas LAI changes were the primary control on maize ET. Spectral vegetation indices (VIs) and TL,Rad were able to track these different responses to drought, but only after controlling for confounding changes in phenology. PLS-R modeling of gs, Tr, and A using hyperspectral data was more accurate when pooling data from both crops together rather than individually. Nonetheless, separated PLS-R crop models are useful to identify the most relevant variables in each crop such as TL,Rad for soybean and hc for maize under our experimental conditions. Interestingly, the most important spectral bands sensitive to drought, derived from PLS-R analysis, were not exactly centered at the same wavelengths of the studied VIs sensitive to drought, highlighting the benefit of having contiguous narrow spectral bands to predict leaf physiology and suggesting different wavelength combinations based on crop type. Our results are only a first but a promising step towards larger scale remote sensing applications (e.g., airborne and satellite). PLS-R estimates of leaf physiology could help to parameterize canopy level GPP or ET models and to identify different photosynthetic paths or the degree of stomatal closure in response to drought.
Verónica Sobejano-Paz; Teis Mikkelsen; Andreas Baum; Xingguo Mo; Suxia Liu; Christian Köppl; Mark Johnson; Lorant Gulyas; Mónica García. Hyperspectral and Thermal Sensing of Stomatal Conductance, Transpiration, and Photosynthesis for Soybean and Maize under Drought. Remote Sensing 2020, 12, 3182 .
AMA StyleVerónica Sobejano-Paz, Teis Mikkelsen, Andreas Baum, Xingguo Mo, Suxia Liu, Christian Köppl, Mark Johnson, Lorant Gulyas, Mónica García. Hyperspectral and Thermal Sensing of Stomatal Conductance, Transpiration, and Photosynthesis for Soybean and Maize under Drought. Remote Sensing. 2020; 12 (19):3182.
Chicago/Turabian StyleVerónica Sobejano-Paz; Teis Mikkelsen; Andreas Baum; Xingguo Mo; Suxia Liu; Christian Köppl; Mark Johnson; Lorant Gulyas; Mónica García. 2020. "Hyperspectral and Thermal Sensing of Stomatal Conductance, Transpiration, and Photosynthesis for Soybean and Maize under Drought." Remote Sensing 12, no. 19: 3182.
Extensive lake shrinkages have been observed in the semiarid Mongolian Plateau over the past several decades, causing a great challenge to the local socio‐economic sustainability and ecological security. However, issue on the dominant drivers of this water loss has not been well addressed. In this work, variations in water area and water level of the Lake Dalinor during the period 1984‐2018 were tracked using the satellite altimetry and Landsat images. Dominant drivers for the derived variations were then investigated based on the SPEI analysis and the VIP model. Results showed that both the water area and water level displayed a two‐stage variation with a slightly increasing trend before 2000 and a drastic decline since 2000 (p<0.01). The SPEI analysis revealed a close relationship between water level variations and the cumulative water anomalies at seasonal and annual scales. The model‐based attribution analysis suggested that climate change and anthropogenic impacts contributed 76.5% and 23.5% of the observed declining trend, respectively. Climate warming and drying dominated the water level decline since 2000, while the large‐scale conversion from the natural grassland to the seeded pasture might have accelerated this water loss process. This study confirmed the prominent impacts of climate warming and drying on the lake desiccation in the semiarid Mongolian Plateau, and highlighted the gradually intensifying impacts of human activities such as grassland conversion on the lake water budget.
Meng Bai; Xingguo Mo; Suxia Liu; Shi Hu. Detection and attribution of lake water loss in the semi‐arid Mongolian Plateau—A case study in the Lake Dalinor. Ecohydrology 2020, 14, 1 .
AMA StyleMeng Bai, Xingguo Mo, Suxia Liu, Shi Hu. Detection and attribution of lake water loss in the semi‐arid Mongolian Plateau—A case study in the Lake Dalinor. Ecohydrology. 2020; 14 (1):1.
Chicago/Turabian StyleMeng Bai; Xingguo Mo; Suxia Liu; Shi Hu. 2020. "Detection and attribution of lake water loss in the semi‐arid Mongolian Plateau—A case study in the Lake Dalinor." Ecohydrology 14, no. 1: 1.
Agricultural water optimization at the basin scale is critical for sustainable irrigated agriculture and water resources management. Crop water production function (CWPF) and surface water are key components of agricultural water optimization. CWPF relates closely to crop yield/growth-related parameters, and surface water of sub-basins is often different and impacted by water withdrawals. However, CWPF accounting for the crop yield-related parameter and natural runoff of sub-basins were scarcely involved in agricultural water optimization at the basin scale. To fill this gap, CWPFs of different water units were estimated using a distributed ecohydrological model involving the spatial heterogeneity of crop photosynthetic capacity parameter, and the natural runoff of sub-basins is reproduced by this model. Integrating these functions and variables, and taking the agricultural benefit of the whole basin as the main objective, an agricultural water optimization model at the basin scale (AWOMB) was developed and applied to a mountain-plain basin in North China. The results showed that agricultural water optimization in a representative year would lead to 0.4% increase of crop production for the whole basin at the expense of certain urban ecological water and equity of agricultural water. In this scenario, the river ecological water requirements in all sub-basins would be satisfied. Assuming the domestic, industrial and river ecological water demand being fully satisfied in 2020s, water deficits will be 8% and 26% for the whole basin under the normal and dry year scenarios, respectively. Correspondingly, increments of 2% and 7% crop production are predicted in these two scenarios by agricultural water optimization. It is demonstrated that water resources management and agricultural production are effectively improved by coupling a distributed ecohydrological model and water resources optimization in the study basin. This research provides a methodology for integrative catchment water resources management.
Farong Huang; Xingguo Mo; Shi Hu; Lanhai Li. Agricultural water optimization coupling with a distributed ecohydrological model in a mountain-plain basin. Journal of Hydrology 2020, 590, 125336 .
AMA StyleFarong Huang, Xingguo Mo, Shi Hu, Lanhai Li. Agricultural water optimization coupling with a distributed ecohydrological model in a mountain-plain basin. Journal of Hydrology. 2020; 590 ():125336.
Chicago/Turabian StyleFarong Huang; Xingguo Mo; Shi Hu; Lanhai Li. 2020. "Agricultural water optimization coupling with a distributed ecohydrological model in a mountain-plain basin." Journal of Hydrology 590, no. : 125336.
Evapotranspiration (ETa) and gross primary productivity (GPP) are two of the key flux indices in a basin system. This study investigated the evolutions of ETa and GPP and the contributions of climate variables and vegetation index over multiple land cover types, simulated by the VIP model (Vegetation Interfaces Processes, RS version) with Terra-Modis 250 m Normalized Difference Vegetation Index (NDVI) dataset in the Ziya-Daqing basins (ZDB), China, during 2001–2015. The nonparametric Mann-Kendall test was used to analyze the changes in ETa and GPP. Contributions to the variations of ETa and GPP were explored using a differential equation method. The analyses revealed that ETa and GPP were high in the eastern plain, and spatial distributions were mainly associated with distributions of the major land-cover types. ETa and GPP showed positive trends in the western Taihang Mountains and negative trends in the eastern plain region. The annual ETa and GPP increased from 2001 to 2015 in most land-use types except cropland and urban. The decreases in ETa and GPP were primarily attributed to solar dimming in cropland and urban. The increases in ETa and GPP mainly occurred in the natural land-cover types (e.g., mixed forest and grassland) as a tradeoff between the positive effect of greening and the negative effect of declined radiation. In ZDB, the contributions of net radiation, air temperature, wind speed, and leaf area index to the change in ETa were − 0.681%, − 0.379%, − 0.032%, and 1.442%, respectively. The contributions of net short-wave radiation, air temperature, relative humidity, and fraction of photosynthetically active radiation to the change in GPP were − 2.411%, 0.085%, − 0.020%, and 10.224%, respectively. Thus, the “greening” was the major reason for ETa and GPP increases in natural vegetations, whereas solar dimming was the major reason for ETa and GPP decreases in cropland.
Yi Liu; Xingguo Mo; Shi Hu; Xuejuan Chen; Suxia Liu. Attribution analyses of evapotranspiration and gross primary productivity changes in Ziya-Daqing basins, China during 2001–2015. Theoretical and Applied Climatology 2019, 139, 1175 -1189.
AMA StyleYi Liu, Xingguo Mo, Shi Hu, Xuejuan Chen, Suxia Liu. Attribution analyses of evapotranspiration and gross primary productivity changes in Ziya-Daqing basins, China during 2001–2015. Theoretical and Applied Climatology. 2019; 139 (3-4):1175-1189.
Chicago/Turabian StyleYi Liu; Xingguo Mo; Shi Hu; Xuejuan Chen; Suxia Liu. 2019. "Attribution analyses of evapotranspiration and gross primary productivity changes in Ziya-Daqing basins, China during 2001–2015." Theoretical and Applied Climatology 139, no. 3-4: 1175-1189.
Identifying the factors driving yield gaps between the attainable and actual yields achieved by farmers is essential for agricultural improvement and water resource management. In this study, the process-based VIP (Vegetation Interface Processes) eco-hydrological model was used to estimate the yield gap of spring maize in the Hutuo River Basin (HRB), North China. To describe the realistic crop growth and attainable yield pattern, the field-sampled grain yield and aboveground biomass were used to design a scheme to retrieve the intrinsic quantum efficiency (εact) for leaf photosynthesis of C4 crop, including the statistical relationships between the intrinsic quantum efficiency, vegetation index and grain yield. The actual yields were predicted with the retrieved intrinsic quantum efficiency pattern, while the attainable yields were predicted with the average of the top 5% intrinsic quantum efficiencies. The simulated actual yields are consistent with the census data at the county level (R2 of 0.37 to 0.74 and relative RMSE of 16–29%). The average yield gap in the basin is 5246 kg ha−1, being 55% of the attainable yield. It is revealed that soil organic matter (SOM) content and depth of soil layer are the principal limiting factors in more than 80% of farmland and results in 70% of the yield gap, while the effects of SOM content is dominant in flat piedmont. Water stress is also a critical factor limiting crop yield, especially for hilly farmlands with slopes greater than 8°. Improving fertilizer management and irrigation techniques in the HRB is therefore the primary task to narrow yield gaps attributable to basin management.
Shi Hu; Xingguo Mo; Farong Huang. Retrieval of photosynthetic capability for yield gap attribution in maize via model-data fusion. Agricultural Water Management 2019, 226, 105783 .
AMA StyleShi Hu, Xingguo Mo, Farong Huang. Retrieval of photosynthetic capability for yield gap attribution in maize via model-data fusion. Agricultural Water Management. 2019; 226 ():105783.
Chicago/Turabian StyleShi Hu; Xingguo Mo; Farong Huang. 2019. "Retrieval of photosynthetic capability for yield gap attribution in maize via model-data fusion." Agricultural Water Management 226, no. : 105783.
Drought is one of the most damaging and complicated disasters in the world. Timely monitoring of droughts over agro-ecosystem is important for reducing yield loss. The potential of satellite-borne solar-induced chlorophyll fluorescence (SIF) for drought detection and assessment were explored in this study. As denoted by the significant negative anomalies of standardized precipitation evapotranspiration index (SPEI), precipitation (PPT), soil moisture (SM) and positive anomalies of land surface temperature (LST) and air temperature difference (DT), a severe drought event was detected at summer maize growth period in 2014 over the North China Plain. In the duration of this drought, the anomalies of SIF and SIFyield (SIF normalized by absorbed photosynthetically active radiation) were negative. The regional averaged SIF and SIFyield declined 9.0% and 9.3% in July, and 11.9% and 12.5% in August, respectively, higher than those of normalized difference vegetation index (NDVI) (4.8% in July and 3.5% in August) and land surface water index (LSWI) (8.2% in July and 4.9% in August). In addition, the linear relationship between gross primary productivity (GPP) and SIF (R2 = 0.85) was more significant than that between GPP and NDVI (R2 = 0.60). The GPP estimated by SIF decreased by 10.6% in counties with severe drought in 2014, which was consistent with the yield reduction (9.1%) estimated by county statistical yield data. It is concluded that satellite SIF is more reliable and effective for regional drought monitoring and assessment, which can help policy-makers or farmers implement appropriate measures to mitigate the drought disasters.
Xuejuan Chen; Xingguo Mo; Yucui Zhang; Zhigang Sun; Yi Liu; Shi Hu; Suxia Liu. Drought detection and assessment with solar-induced chlorophyll fluorescence in summer maize growth period over North China Plain. Ecological Indicators 2019, 104, 347 -356.
AMA StyleXuejuan Chen, Xingguo Mo, Yucui Zhang, Zhigang Sun, Yi Liu, Shi Hu, Suxia Liu. Drought detection and assessment with solar-induced chlorophyll fluorescence in summer maize growth period over North China Plain. Ecological Indicators. 2019; 104 ():347-356.
Chicago/Turabian StyleXuejuan Chen; Xingguo Mo; Yucui Zhang; Zhigang Sun; Yi Liu; Shi Hu; Suxia Liu. 2019. "Drought detection and assessment with solar-induced chlorophyll fluorescence in summer maize growth period over North China Plain." Ecological Indicators 104, no. : 347-356.
Attributing vegetation changes provide fundamental information for ecosystem management, especially in mountainous areas which has vulnerable ecosystems. Based on the Normalized Difference Vegetation Index (NDVI) data, the spatial-temporal change of vegetation was detected in Taihang Mountain (THM) from 2000 to 2014. The topographical factors were introduced to interpret the response of vegetation variation to climate change and human activities. Results showed that the avegaged NDVI during growing season showed a single-peak curve distribution, with the largest value (0.628) among 1600–1800 m. A significant greening trend was detected in THM, with the largest increasing rate (0.0078 yr-1) among the elevation of 1600–1800 m and slope gradient between 3~5°. The partial correlation and multiple correlation analyses indicated that vegetation variation in more than 81.8% pixels of the THM was mainly impacted by human activities. In the low elevation zones less than 1000 m, increasing precipitation is the principle factor promoting vegetation restoration, whereas in the high elevation zones of THM, temperature is the restricted factors impacting vegetation variation. Considering the dramatic climate change in the future, further studies should be conducted to explore inherent mechanism of vegetation growth to dynamic environment changes.
Shi Hu; Fei-Yu Wang; Che-Sheng Zhan; Ru-Xin Zhao; Xiong-Guo Mo; Liang-Mei-Zi Liu. Detecting and attributing vegetation changes in Taihang Mountain, China. Journal of Mountain Science 2019, 16, 337 -350.
AMA StyleShi Hu, Fei-Yu Wang, Che-Sheng Zhan, Ru-Xin Zhao, Xiong-Guo Mo, Liang-Mei-Zi Liu. Detecting and attributing vegetation changes in Taihang Mountain, China. Journal of Mountain Science. 2019; 16 (2):337-350.
Chicago/Turabian StyleShi Hu; Fei-Yu Wang; Che-Sheng Zhan; Ru-Xin Zhao; Xiong-Guo Mo; Liang-Mei-Zi Liu. 2019. "Detecting and attributing vegetation changes in Taihang Mountain, China." Journal of Mountain Science 16, no. 2: 337-350.
Significant increases in vegetation cover on the Loess Plateau since the early 2000s have been well documented. However, the relevant hydrological effects are still unclear. Here, we investigated the changes in actual evapotranspiration (ETa) from 2000 to 2016 and related them to climate change and vegetation greening in Yanhe River basin (YRB), a typical hilly-gully basin on the Loess Plateau, by using the remote-sensing based VIP model. Results showed that the annual ETa in the YRB increased significantly with a trend of 3.45 mm yr−1 (p < 0.005) and changes of ETa in summer months dominated the annual trend. Partial correlation analysis suggested that vegetation greening was the dominant driving factor of ETa inter-annual variations in 56% area of YRB. Model simulation experiments illustrated that relative contributions of NDVI, precipitation, and potential evapotranspiration (ETp) to the ETa trend were 93.0%, 18.1%, and −7.4%, respectively. Vegetation greening, which is closely related to the Grain for Green (GFG) afforestation, was the main driver to the long-term tendency of water consumption in the YRB. This study highlights potential water demanding conflicts between the socio-economic system and the natural ecosystem on the Loess Plateau due to the rapid vegetation expansion in this water-limited area.
Meng Bai; Xingguo Mo; Suxia Liu; Shi Hu. Contributions of climate change and vegetation greening to evapotranspiration trend in a typical hilly-gully basin on the Loess Plateau, China. Science of The Total Environment 2018, 657, 325 -339.
AMA StyleMeng Bai, Xingguo Mo, Suxia Liu, Shi Hu. Contributions of climate change and vegetation greening to evapotranspiration trend in a typical hilly-gully basin on the Loess Plateau, China. Science of The Total Environment. 2018; 657 ():325-339.
Chicago/Turabian StyleMeng Bai; Xingguo Mo; Suxia Liu; Shi Hu. 2018. "Contributions of climate change and vegetation greening to evapotranspiration trend in a typical hilly-gully basin on the Loess Plateau, China." Science of The Total Environment 657, no. : 325-339.
A hydroeconomic optimization modelling framework for joint water allocation and water quality management is presented in this study. Water resources planning is often limited to water quantity, even though water quantity and quality are interdependent. Including water quality in a hydroeconomic optimization model increases complexity and uncertainty. In this study, the problem is addressed with a multi-reservoir, multi-temporal, multi-objective linear optimization model with fixed but spatially variable water quality. Model complexity is kept at a manageable level, leading to limited demand for computational resources, despite a high spatial resolution and representation of both surface water and groundwater resources. The model is applied to Haihe River basin, a water-scarce and highly polluted river basin in China. Economic trade-offs between limiting groundwater overdraft and sub-basin specific costs as well as maps of water availability shadow prices are presented. Adding water quality to the model framework impacts water availability shadow prices, which can influence model-based decision support. If groundwater abstractions are limited to sustainable levels, Haihe River basin will benefit from increasing inter-basins transfers and groundwater recharge to the shallow plain area aquifer. A scenario analysis showed that managed aquifer recharge in the plain area is also a feasible adaptation strategy.
Grith Martinsen; Suxia Liu; Xingguo Mo; Peter Bauer-Gottwein. Joint optimization of water allocation and water quality management in Haihe River basin. Science of The Total Environment 2018, 654, 72 -84.
AMA StyleGrith Martinsen, Suxia Liu, Xingguo Mo, Peter Bauer-Gottwein. Joint optimization of water allocation and water quality management in Haihe River basin. Science of The Total Environment. 2018; 654 ():72-84.
Chicago/Turabian StyleGrith Martinsen; Suxia Liu; Xingguo Mo; Peter Bauer-Gottwein. 2018. "Joint optimization of water allocation and water quality management in Haihe River basin." Science of The Total Environment 654, no. : 72-84.
兴国 莫; Mo Xing-Guo; 实 胡; 洪健 卢; 忠辉 林; 苏峡 刘; Hu Shi; Lu Hong-Jian; Lin Zhong-Hui; Liu Su-Xia. GCM预测情景下中国21世纪干旱演变趋势分析. JOURNAL OF NATURAL RESOURCES 2018, 33, 1244 -1256.
AMA Style兴国 莫, Mo Xing-Guo, 实 胡, 洪健 卢, 忠辉 林, 苏峡 刘, Hu Shi, Lu Hong-Jian, Lin Zhong-Hui, Liu Su-Xia. GCM预测情景下中国21世纪干旱演变趋势分析. JOURNAL OF NATURAL RESOURCES. 2018; 33 (7):1244-1256.
Chicago/Turabian Style兴国 莫; Mo Xing-Guo; 实 胡; 洪健 卢; 忠辉 林; 苏峡 刘; Hu Shi; Lu Hong-Jian; Lin Zhong-Hui; Liu Su-Xia. 2018. "GCM预测情景下中国21世纪干旱演变趋势分析." JOURNAL OF NATURAL RESOURCES 33, no. 7: 1244-1256.
Accurately estimating regional water and vegetation carbon fixation and understanding their co-variation mechanisms will benefit regional water resources and ecosystem management. The process-based VIP (Vegetation Interface Processes) model was employed to simulate the spatiotemporal variations of evapotranspiration (ET) and vegetation gross primary production (GPP) over the landmass of China, by integrating the 8-day Terra-Modis leaf area index dataset from 2000 to 2013. It is found that there are remarkable spatial variations in annual ET and GPP across the country, top values being around 1200 mm for ET and 3000 gC m-2 for GPP mostly occurred in the southern rainforests. Average annual ET and GPP are weakly increasing, in which about one third is significant. At annual scale, variability of ET follows precipitation variations, while variability of GPP follows variations of both precipitation and leaf area index (LAI). At monthly scale, variations of ET and GPP are more correlated with net radiation than precipitation. It is revealed that the climatic factors dominating water and carbon fluxes are different over the typical climate zones. The increasing GPP and water use efficiency (WUE) are benefitting the regional vegetation recovery and carbon fixation, however more water consumption may exaggerate the ecosystem vulnerability in water-limited zones.
Xingguo Mo; Suxia Liu; Xuejuan Chen; Shi Hu. Variability, tendencies, and climate controls of terrestrial evapotranspiration and gross primary productivity in the recent decade over China. Ecohydrology 2018, 11, e1951 .
AMA StyleXingguo Mo, Suxia Liu, Xuejuan Chen, Shi Hu. Variability, tendencies, and climate controls of terrestrial evapotranspiration and gross primary productivity in the recent decade over China. Ecohydrology. 2018; 11 (4):e1951.
Chicago/Turabian StyleXingguo Mo; Suxia Liu; Xuejuan Chen; Shi Hu. 2018. "Variability, tendencies, and climate controls of terrestrial evapotranspiration and gross primary productivity in the recent decade over China." Ecohydrology 11, no. 4: e1951.
Quantifying the contributions of climate change and human activities to ecosystem evapotranspiration (ET) and gross primary productivity (GPP) changes is important for adaptation assessment and sustainable development. Spatiotemporal patterns of ET and GPP were estimated from 2000 to 2014 over North China Plain (NCP) with a physical and remote sensing-based model. The contributions of climate change and human activities to ET and GPP trends were separated and quantified by the first difference de-trending method and multivariate regression. Results showed that annual ET and GPP increased weakly, with climate change and human activities contributing 0.188 mm yr–2 and 0.466 mm yr–2 to ET trend of 0.654 mm yr–2, and–1.321 g C m–2 yr–2 and 7.542 g C m–2 yr–2 to GPP trend of 6.221 g C m–2 yr–2, respectively. In cropland, the increasing trends mainly occurred in wheat growing stage; the contributions of climate change to wheat and maize were both negative. Precipitation and sunshine duration were the major climatic factors regulating ET and GPP trends. It is concluded that human activities are the main drivers to the long term tendencies of water consumption and gross primary productivity in the NCP.
Xuejuan Chen; Xingguo Mo; Shi Hu; Suxia Liu. Contributions of climate change and human activities to ET and GPP trends over North China Plain from 2000 to 2014. Journal of Geographical Sciences 2017, 27, 661 -680.
AMA StyleXuejuan Chen, Xingguo Mo, Shi Hu, Suxia Liu. Contributions of climate change and human activities to ET and GPP trends over North China Plain from 2000 to 2014. Journal of Geographical Sciences. 2017; 27 (6):661-680.
Chicago/Turabian StyleXuejuan Chen; Xingguo Mo; Shi Hu; Suxia Liu. 2017. "Contributions of climate change and human activities to ET and GPP trends over North China Plain from 2000 to 2014." Journal of Geographical Sciences 27, no. 6: 661-680.