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Objectives: The Greenland ice sheet is one of the main contributors to the global sea level rise, and the mass loss caused by its surface melting and meltwater runoff accounts for about 60% of the total mass loss of the ice sheet, so it is of great significance to study the surface melting of the Greenland ice sheet. Methods: Based on the 37 GHz vertical polarization passive microwave data of special sensor microwave imager sounder, the advanced diurnal amplitude variations (ADAV) method is proposed to detect the surface melting of the Greenland ice sheet. Results: Compared with the air temperature data of automatic weather stations, the average accuracy of the detection results of the ADAV method using dynamic threshold is better than that of the traditional diurnal amplitude variations method using a fixed threshold, and the passive microwave data time has no obvious influence on the detection accuracy. Conclusions: The freezethaw analysis of the Greenland ice sheet based on this method found that in 2019, the area with the most melting days on the ice sheet melted up to 165 d. The melting area reached the maximum on July 31st, accounting for 67% of the total ice sheet area. Three melting peaks arose in summer, and there were sever winter melting events on the south coast. The ADAV method and its application to high spatial resolution passive microwave data have promoted the development of refining ice sheet freezing and thawing observations. [ABSTRACT FROM AUTHOR]

[Objective The aims of this study are to analyze the response of farmland surface runoff and sediment loss to rainfall patterns under different planting modes, to explore the laws of farmland surface runoff and sediment transport in the Poyang Lake plain area under new circumstances, and to provide scientific basis for preventing and controlling farmland surface soil erosion, [Methods] 64 rainfall events were classified using K-means clustering method, and combined with monitoring data such as runoff and sediment production in runoff plots, the impact of surface runoff and sediment losses in different rainfall types of farmlands under three planting modes were analyzed. Results] (1) The duration, rainfall and maximum rainfall intensity of 30 minutes were taken as the rainfall characteristic indicators. The rainfall could be divided into 4 types (type A: 'medium duration, small rainfall and light rainfall intensity', type B: 'short duration, small rainfall and medium rainfall intensity', type C: 'long duration, heavy rainfall and medium rainfall intensity', and type D: short duration, medium rainfall and heavy rainfall intensity'). (2) The variation of runoff and rainfall of each planting mode was basically the same, and the runoff was also more when the rainfall was larger. In each month dry farming mode produced the most runoff, (3) No matter what type of rainfall, the runoff and sediment losses of dry farming mode were the highest. Under the types A and C. the runoff and sediment yields of water farming mode were the lowest. Under the type B. the runoff reduction effect of water and dry rotation mode was the best. (4) There were significant differences in the total runoff and sediment loss under different planting modes, and the performance followed the order: dry farming mode paddy upland rotation mode paddy farming mode. [Conclusion In conclusion. compared with the dry farming model, the water farming model has certain advantages in reducing runoff and sediment, especially when dealing with type A and type C. the effect of runoff and sediment reduction is more obvious. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to assess the accuracy of soil erodibility K calculated by different methods in the key soil loss areas of Anhui Province, and to refine each calculation method based on the measured erodibility K. [Methods] The Nomo equation, modified Nomo equation, EPIC model, DG model and Torri model were utilized to estimate the soil erodibility K values. Based on monitoring data from runoff plots in Huoshan County, Guangde County, Yuexi County and She County, the actual erodibility factor K values were obtained to evaluate the effectiveness of each method. [Results] The soil erodibility K values in Huoshan County, Guangde County, Yuexi County and She County were 0.033~0.035, 0.018, 0.021 and 0.041 (thm² h)/(hm² MJ mm), respectively. The differences in soil erodibility K values derived from different methods were significant, with all methods greatly overestimating the K values. The overall ranking of the methods in terms of soil erodibility followed the order: K Torri> K Noma> KM-Nomo >K DG> K Epic. The methods of calculating K values for each were improved, in which the improved Nomo equation and the modified Nomo equation showed superior performance. [Conclusion] The improved Nomo equation and modified Nomo equation are recommended to apply in the key soil loss areas of Anhui Province. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the influence of slope, rainfall pattern and sugarcane growth period on soil erosion and nutrient loss on slope surface, and to provide theoretical basis for the mechanism improvement and prevention of soil erosion in sugarcane planting area of lateritic soil. [Methods] In-situ observation method in runoff area was used to explore the characteristics of soil erosion and loss of nitrogen nutrients (nitrate nitrogen and ammonium nitrogen) at different slopes (5° and 10°) under different rain types and sugarcane growth period. [Results] (1) The runoff in each growth period decreased in the order; extension period tillering periodseedling period mature period, and the nitrogen loss in tillering period was significantly higher than that in the other three periods (2.6~905.2 times). The sediment yield and their nitrogen nutrient loss followed the order: tillering stage extension period seedling period maturity period, the sediment yield of sugarcane in the tillering stage was significantly higher than that in other periods (2.9~71.4 times), and the difference was more obvious under the 10° slope. (2) Type B (medium rainfall depth, short duration, strong rainfall intensity) and type C (great rainfall depth, short duration, extremely strong rainfall intensity) were the main rainfall pattern that caused soil erosion and the nitrogen nutrient loss in sugarcane in the research area, contributing more than 70% of the slope runoff, sediment yield and nitrogen loss. In different slope treatments, there were significant differences in the sediment amount under type C, sediment ammonium nitrogen loss under type A and runoff ammonium loss under type B. (3) Rain pattern and sugarcane growth period had significant effects on runoff, sediment and those nitrogen loss on sugarcane slope (p<0.01), and the effect was higher than that of slope, interaction between slope and rain pattern, interaction between slope and growth period. Compared with runoff and those nitrogen loss, slope and its interaction with rain pattern and growth period showed more prominent effects on erosion sediment and nitrogen loss. [Conclusion] The slope had a more significant influence on the sediment and nitrogen nutrient loss process of sugarcane slope. The soil erosion and nitrogen nutrient loss were greatest in the tillering period, mainly contributed by type B and type C. [ABSTRACT FROM AUTHOR]

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The inland river basin in Hexi, Gansu Province, is extremely short of water resources. There are certain differences in the changes of mountain runoff between the central and western and eastern water systems in the basin. Studying the changes in mountain runoff and the contribution rates of different factors is of great significance for ensuring the sustainable development and utilization of regional water resources. Based on the data of mountain runoff and precipitation and temperature in the main runoff producing areas from 1956 to 2021, various trends and mutation tests, cumulative slope change rate methods, and combined with the characteristics of runoff supply, the changes in mountain runoff and their responses to changes in precipitation and temperature in the three major water systems were analyzed. The results show that: 1 the average annual mountain runoff of the Shiyang River system was 1.36 billion m³, showing a non-significant decreasing trend over the years and a non-significant increasing trend in precipitation, The significant increase in temperature leads to an increase in evaporation, resulting in a decrease in runoff; 2 The average annual runoff from the Heihe River system has increased from 3.062 billion m³ before the mutation point in 2006 to 3.56 billion m³ after the mutation point. The contribution rate of precipitation to runoff changes is 16.7%, and the temperature has significantly increased, enhancing the impact on runoff changes; 3 The average annual runoff from the Shule River system has increased from 1.422 billion m3 before the mutation point in 1998 to 17.93 m3 after the mutation point. The impact of precipitation and temperature on runoff changes is similar, with contribution rates of 30.4% and 30.2%, respectively. There are certain differences in run-off supply characteristics and climate conditions among the three major inland river systems in Hexi, resulting in inconsistent responses of runoff to different driving factors. [ABSTRACT FROM AUTHOR]

Copyright of Acta Scientiarum Naturalium Universitatis Pekinensis is the property of Editorial Office of Acta Scientiarum Naturalium Universitatis Pekinensis and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of South-Central Minzu University (Natural Science Edition) is the property of Journal of South-Central Minzu University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Glacial lake area change is an indicator of global climate change. The topography of Tianshan Mountains is complex, and the glacial lakes are widely distributed, so their variation characteristics and response mechanism to climate change need to be further explored. Based on the Google Earth Engine (GEE) platform, this paper studied the changes of glacial lakes in the Tianshan Mountains in the past 20 years, and analyzed the driving forces in combination with precipitation and temperature. The results showed that: (1) There were 1532 glacial lakes in Tianshan Mountains in 2020, with an area of 164.02 km². The distribution of glacial lakes in the Tianshan Mountains was characterized by more in the west and less in the east, and glacial lake area with an annual average growth rate of 3.47% and 0.63% in the east and west, respectively. (2) The glacial lakes at lower altitudes (<3600 m) in the study area generally showed an expanding trend, and the glacial lakes with an area <0.1 km2 showed a more obvious change. (3) The results of the geographic detector showed that temperature and glaciers were the main driving factors affecting the change of the glacial lakes in Tianshan Mountains. From 2000 to 2020, the precipitation in the eastern Tianshan Mountains increased significantly, while the temperature showed an insignificant trend of decrease. The glacial lake area in this region continued to expand under the stable and sufficient glacial meltwater and runoff recharge. Research results can provide scientific basis for the rational development of water resources and the risk assessment of glacial lake outburst disaster in the Tianshan Mountains. [ABSTRACT FROM AUTHOR]

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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

【Objective】 Drainage modulus is an important parameter for designing drainage systems in farmland. Taking Suibin county in Sanjiang Plain as an example, this paper analyzes its runoff and drainage modulus. 【Method】 The study site was an area prone to waterlogging. We first calculated the runoff (RO) using historical data on precipitation, pumping stations and land usage, and then estimated it using the runoff generation method (RGM) and the SCS-CN method (RSCS). The drainage modulus associated with each runoff was calculated using both empirical formulae (QE) and the average draining method (QA). The runoff and drainage modulus calculated by different methods were tested against measured data in the field. 【Result】 In the same year and under the same rainfall return period, the measured runoff increased with rainfall duration, while under the same rainfall duration and the same rainfall return period, it decreased with passage of years. The runoff and drainage modulus calculated from different methods differed from the experimentally measured data. For heavy rainfalls, the runoff estimated from different methods was ranked in the order of RGM>RSCS>RO, while for other rainfalls, it was ranked in the order of RSCSQE, whereas for rainfalls lasting 3 days, QA

[Objective] In order to clarify the law of sediment yield and sediment loss of different land use types under different rainfall types, and to evaluate the benefit of sediment reduction of different land use types under different rainfall types. [Methods] Based on the monitoring data of runoff and soil loss under natural rainfall conditions over 2015—2016 in 31 runoff plots located in the Loess Plateau of China the characteristics of sediment yield and loss in different land use types, including farmlands, abandoned lands, artificial grasslands, natural grasslands, shrublands and artificial forest lands were discussed. The efficiency of runoff and sediment reduction for each land use type under different rainfall types was determined. [Results] The runoff and soil loss of abandoned lands were the largest (30 mm, 86 t/hm2) and artificial forest lands were the smallest (8 mm, 24 t/hm2) under the annual rainfall scale, and there was no significant difference between other land use types. Through the application of duster analysis a total of 120 rainfall events were categorized into three distinct rainfall types based on criteria that included amount, duration, and maximum intensity of rainfall in a 30-minute period. That is, Rainfall Type I: characterised by moderate rainfall duration (749 min), moderate rainfall volume (35.4 mm), and moderate rainfall intensity (16.9 mm/h); Rainfall Type II: comprising short-duration rainfall (222 min), moderate rainfall volume (25.2 mm), and intense rainfall intensity (23.8 mm/h); Rainfall Type III: involving a long duration of rainfall (1 451 min), substantial rainfall volume (40.6 mm), but low intensity of rainfall (11.5 mm/h). When considering the impact of these types of rainfall within the given scale, the study observed the following trends, for the runoff coefficient, exhibiting Rainfall Type II > Rainfall Type III > Rainfall Type I, while for soil loss, exhibiting Rainfall Type II > Rainfall Type I > Rainfall Type III. The runoff coefficient of Rainfall Type I was significantly higher than that of other land use types, reaching 17.7%, which was 2.36 times that of artificial forest land. There were no significant difference in runoff coefficient under Rainfall Type II, and the average runoff coefficient was 19.9%. The runoff coefficient of abandoned lands, artificial grasslands, natural grasslands, and farmlands (average of 14.3%) was significantly higher than that of shrublands and artificial forest lands (averaging at 9.0%). The soil loss of famlands, artificial grasslands, shmblands and artificial forest lands under Rainfall Type II (3.94, 0.87, 1.06, 1.08 t/hm2) > Rainfall Type I (1.60, 0.60, 0.59, 0.63 t/hm2) > Rainfall Type III (0.09, 0.20, 0.06, 0.04 t/hm2). [Conclusion] In the Loess Plateau, the artificial forest land was the first choice to control soil and water loss effectively under the condition of medium-low rainfall intensity and medium-long duration rainfall, and the soil and water conservation effect of shrubland and grassland was better under short-duration heavy rainfall.

Qinghai Lake is not only the largest lake in China but also an important part of the national ecological security strategy.Under the background of global warming， the water level of Qinghai Lake changes rapidly， which has great effects on the surrounding traffic facilities， residents' safety and the development of animal husbandry， etc.Therefore， it is necessary to study the water level evolution characteristics of Qinghai Lake and its water balance under climate change.Based on the hydrological data of Buha River hydrology station and Xiashe hydrology station， meteorological data of Gangcha meteorological station and CMFD， and water balance equation， this paper first analyzes the inter-annual and intra-year water level evolution characteristics of Qinghai Lake from 1956 to 2020， and the water balance components， such as runoff into the lake （Rs）， precipitation （P） and evaporation （E）.The second reveals that the changes in water level values calculated in the same months are synchronized with the changes in Rs， P， and E.Finally， the ridge regression method is employed to quantitatively calculate the contribution rates of Rs， P， and E to the water level change of Qinghai Lake based on calculations made for December.The results show that the annual average water level declined at a rate of 0.8 m·（10a）-1 from 1956 to 2004， of which the main reason for the decrease between 1979 and 2004 was that E exceeded the sum of P and Rs.However， from 2004 to 2020， the water level increased at a rate of 1.9 m·（10a）-1， of which the main reason for the increase between 2004 and 2018 was the increase of P and Rs.Qinghai Lake exhibits evident intra-annual variations， with the water level starting to rise in May and reaching its peak in September， which aligns with the monthly variations of Rs， P， and E.Furthermore， the impact of the current year's P， Rs， and E changes on the annual water level change for the same months of September to December is greater than that of the previous year.Specifically， the contributions of the current year's P， Rs， and E changes to the water level change calculated based on December data are 10%， 70%， and 20%， respectively.

With the global climate change intensified, Chinese regional water resources shortage is becoming increasingly serious. Using adequate method to study the varied pattern on runoff is particularly important for water resources planning and management. Based on the time series of mountain runoff from 1956 to 2018 in Shiyang River Basin, the periodic change, abrupt change and trend change of mountain runoff series in Shiyang River Basin were analyzed by using extreme-point symmetric mode decomposition (ESMD) method, and the Morlet wavelet analysis method, Mann-Kendall test method and R/S analysis method were used for comparative verification analysis. The results show that the ESMD method can analyze and process runoff data efficiently. The runoff series of Shiyang River has periodic changes of 3.0 years, 7.3 years, 12.6 years, and the time of mutation is different under different time scales, and the time of abrupt change in different time scales is also different. And forecast shows that the runoff in Shiyang River Basin will continue to increase in short term, but it will inevitably decrease in the long term. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the scale effect in the process of runoff and sediment movement on the slope, to clarify the scale effect influence mechanism of runoff and sediment movement in the hilly and gully region of the Loess Plateau, so as to provide scientific support for the study of runoff and sediment transfer mechanism and the comprehensive management of runoff and sediment in the Yellow River Basin. [Methods] Based on the runoff and sediment data of four runoff fields in Zizhou runoff test station of the Yellow River, the scale transfer effect of runoff and sediment yield on slope was revealed by comparing and analyzing the runoff and sediment yield processes of different slope lengths under rainfall events. The concept of scale transfer efficiency was proposed to characterize the runoff and sediment transfer relationship between the upper and lower levels, and to further explore the influencing factors on runoff and sediment transfer efficiency. [Results] (1) The characteristics of different rainfall types had different effects on the runoff and sediment yield on the slope. The rainfall duration mainly affected the runoff and sediment yield on the slope, and the average rainfall intensity mainly affected the starting time of runoff and sediment yield on the slope. (2) Under the event of rainfall, the runoff transfer of different slope lengths was an ideal equilibrium transfer mechanism, and with the increase of slope length, the transfer capacity of runoff showed a decreasing trend. Under the condition of 40~60m slope length, the transfer of sediment was a non- equilibrium transfer process. With the increase of slope length, the transfer capacity of sediment increased first and then decreased. (3) The influencing factors on flow-sediment transfer efficiency on different scale slopes were different. Runoff depth, average rainfall intensity and surface soil moisture content after rain were the main factors affecting the transfer efficiency of flow-sediment scale. [Conclusion] The runoff and sediment yield capacity of the slope in the loess hilly and gully region is affected by rainfall characteristics and slope length. There is a significant scale effect of damage or gain in the transmission of runoff and sediment along the way. The efficiency of water and sediment transport is regulated by multiple factors such as rainfall intensity, runoff and soil moisture. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to investigate the spatial and temporal changes of runoff and sediment load in the Kuye River Basin, to quantify the contribution of climate change and human activities to variation of runoff and sediment load, and to provide scientific basis for the rational use of water resources and the optimal allocation of soil and water conservation measures in the Kuye River Basin. [Methods] Based on the runoff, sediment load and rainfall data of Xinmiao, Wangdaohengta, Shenmu and Wenjiachuan hydrological stations in Kuye River Basin from 1960 to 2020, the spatial and temporal variation characteristics of runoff and sediment load were analyzed by the linear trend method, Mann-Kendall trend test and Pettitt mutation test, and the double mass curve was used to quantitatively analyze the contribution rate of climate change and human activities to runoff and sediment load variation in different periods. [Results] Annual runoff and sediment load in the Kuye River Basin showed a significant decreasing trend from 1960 to 2020 (p<0.01). The runoff reduction rates of Xinmiao, Wangdaohengta, Shenmu and Wenjiachuan hydrological stations were 2.4 million m³/a, 3.4 million m³/a, 8.1 million m³/a, 10.6 million m³/a, the reduction rates of sediment load were 0.438 million t/a, 0.693 million t/a, 1.603 million t/a and 2.721 million t/a, respectively. The annual runoff and sediment load of each hydrological station changed abruptly both in 1979 and 1996, so the runoff and sediment load sequences could be divided into the reference period (1960-1979, P1) and the change period (1980-1996, P2;1997-2020, P3). During the study period, the average annual runoff depth and sediment load modulus of different sub-basins showed a decreasing trend, but there were differences in space. [Conclusion] The increasing human activities (water conservancy and soil conservation measures, coal mining, etc.) are the dominant factors on variation of runoff and sediment load in the Kuye River Basin. Compared with the base period, the runoff and sediment load of each hydrological station decreased in both P2 and P3 periods, and reduction was more intense in P3 period. In the P2 and P3 periods, the contribution of human activities to the reduction of runoff sediment transport was higher than that of rainfall changes. [ABSTRACT FROM AUTHOR]

[Objective] This study aims to explore the variation characteristics of streamflow components and baseflow index (BFI) in the Tuweihe River Basin, to clarify the impact of environmental factors on their variations, to identify the dominant factors, and to provide scientific basis for watershed water resources management. [Methods] Tuweihe River Basin in the middle reaches of the Yellow River was taken as the study area. The changes of surface runoff, baseflow and baseflow index (BFI) during the period 1958-2017 were analyzed. The correlation analysis and elasticity coefficient methods were employed to qualitatively and quantitively analyze the influence of environmental factors on them. [Results] The surface runoff and baseflow significantly decreased at a rate of 4.55 and 9.73 mm/decade (p<0.01), respectively, while the BFI showed a significant upward trend (p<0.05). Surface runoff (or baseflow, BFI) was highly sensitive to the changes in potential evapotranspiration, normalized difference vegetation index (NDVI), and volumetric soil water. The changes in NDVI and potential evapotranspiration contributed to the majority of the changes in surface runoff (-34% and -29%), baseflow (-39% and -29%), and BFI (33% and 31%). [Conclusion] The direct and potential hydrological effects of vegetation restoration play an important role in reducing the streamflow components. The changes of streamflow components as well as their relations to environmental changes provide a theoretical basis for the sustainability of water resources and vegetation. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to explore the change characteristics and driving factors of runoff and sediment load in the Weihe River Basin, and to provide scientific basis for water resource management and ecological environment construction in the Weihe River Basin. [Methods] Based on the measured precipitation, runoff and sediment load data of Huaxian and Zhuangtou hydrological stations in the Weihe River Basin from 1957 to 2019, the trend and the change-point year of annual precipitation, runoff and sediment load were analyzed by modern mathematical statistical. The contribution rates of runoff and sediment load reduction in Weihe River Basin were calculated. The main influencing factors of human activities on runoff and sediment load changes in the Weihe River were discussed. [Results] There was a strong decreasing trend in runoff and sediment load of Weihe River Basin from 1957 to 2019 (p<0.01), and the annual precipitation fluctuated randomly and had no obvious change trend. Abrupt year analyses showed that more rapid declines for runoff began in 1990 (p<0.01), and sediment load began in 1996 (p<0.01). The contribution rates of precipitation to the reduction of runoff and sediment load were 19% and 17%, respectively. The contribution rates of runoff and sediment load reduction caused by human activities were 81% and 83%, respectively. [Conclusion] Human activities are the main reason for the significant reduction of runoff and sediment load in the Weihe River Basin. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to analyze the runoff and sediment under different land use types and slopes in the loess hilly area of western Henan, and to provide scientific basis for quantitative evaluation of soil erosion and comprehensive prevention of soil erosion. [Methods] Based on the observation data of 12 runoff plots from 2011 to 2020 at the monitoring site of soil and water conservation in Hugou small watershed, Songxian County, Henan Province, the pattern of runoff and sediment under different land use was revealed. Correlation analysis was used to detect the relationship between rainfall characteristics, slope, land use, runoff and sediment yield. [Results (1) Compared with bare land plot, grassland plot had the greatest effect on runoff and sediment reduction. The average annual runoff reduction effect of grassland was 78.6%~85.9%, and the maximum sediment reduction effect was 100%. The runoff reduction effect of forestland was 32.9%~51.3%, and the sediment reduction effect was 55.3%~78.9%. (2) Runoff and sediment in each runoff plot and the slope were closely related. There was no significant difference between the runoff and sediment on the slopes of 10° and 15°, however, it increased significantly on the slope of 25°. In addition, with the increase of slope gradient, the soil and water conservation effect of forestland and grassland also reduced. (3) The correlation between runoff depth and maximum 30-minute rainfall intensity (130) and soil loss and rainfall erosivity were the most significant. [Conclusion] In areas where runoff and sediment localization observation is lacking in the loess hilly region of western Henan Province, rainfall process information can be used to estimate the runoff and soil loss under certain slope and vegetation conditions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Soil & Water Conservation (1009-2242) is the property of Institute of Soil & Water Conservation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Elucidating the impact of climate change on watershed hydrological model parameters is a fundamental scientific issue for analyzing parameter transferability and estimating future water balance components. Based on meteorological data from three global climate models (CNRM, IPSL and MRI) under the CMIP6 framework, the HBV hydrological model was used to simulate monthly runoff changes in the Ganjiang River basin from 2015 to 2100. The sensitivity and uncertainty of typical parameters controlling runoff simulation processes under climate change were quantified and evaluated. The major findings of this research are as follows: ① In scenarios where future precipitation either increases or decreases, the sensitivity of model parameters is generally higher relative to the stable precipitation scenario, with the soil module parameters (which calculate soil evapotranspiration and water content) being most sensitive. ② The amount and intra- annual distribution of precipitation could influence parameters′ sensitivity. ③ If future climate change would significantly alter the proportions of runoff components (fast and slow flow), particularly under future scenarios of increased precipitation, more attention should be paid to the response module parameters. [ABSTRACT FROM AUTHOR]

Tributary- mouth channels of mountain rivers are affected by the game between the tributary and main stream, the water and sediment characteristics of which are characterized by both natural rivers and the reach affected by backwater from the main stream. Analyzing the water and sediment conditions of the tributary and main stream, the confluence characteristics, the backwater effects is of great significance for studying the tributary- mouth channel regulation. Taking mouth of Minjiang River as an example, a joint distribution function model of daily mean discharge during the recession period of Jinsha River and Minjiang River was constructed based on the Copula function theory and a function for the low water tributary- mouth channel formation was established using measured hydrologic and sediment data of Jinsha River and Minjiang River during 1960—2020. A quantitative method for determining the shoal-regulation stage of tributary-mouth channel was proposed. The study produced some important results: ① The annual runoff and sediment runoff showed significant decreasing trends, whereas the runoff during the dry season showed significant increasing trends in the Lower Minjiang River affected both by the large- scale development and construction of reservoirs in the upper reaches and human activities. ② The backwater effect of the Jinsha River on the mouth of Minjiang River was generally stronger during the flood season than that during the dry season which provided favorable conditions for scouring the channel during the period from the end of the flood season to the dry season and maintaining the mouth channel depth of Minjiang River. ③ The backwater height at mouth of Minjiang River increased with the increase of the confluence ratio, and there was a significant positive linear correlation between them. ④ The regulation stage should follow the principle of being 1. 5 meters above the designed minimum navigable stage in the fluctuant backwater zone upstream of Yangjiaoshi, and should gradually increase from 1. 5 to 2. 0 meters above the designed minimum navigable stage in the reach between Yangjiaoshi and Yangjiatan. [ABSTRACT FROM AUTHOR]

Under the action of rainfall and slope runoff, the exposed slopes are prone to erosion and collapse, which are put forward higher requirements for the mechanical and water stability of slope protection substrate. Based on the introduction of GFS functional materials such as guar gum, wood fiber and super absorbent polymer (SAP), the mechanical strength and water stability of the ecological substrate under different proportions were compared through direct shear test, disintegration test, penetration test, planting test and slope model erosion test. Meanwhile, the response surface methodology and microscopic test were used to explore the influence degree of different additive materials on the performance of substrate. The results show that ① there are optimal contents of functional materials to enhance the mechanical strength and water stability of substrate; the optimal contents are 1.0% guar gum, 1.5% wood fiber and 0.1% SAP. ② The guar gum and wood fiber enhance the shear strength of substrate, SAP improves the soil and water retention capacity ofsubstrate, the shear strength of substrate first increases and then decreases with the increase of guar gum and wood fiber contents. ③ The rational addition of functional materials significantly improve the water stability of substrate; guar gum in combination with an appropriate amount of wood fiber effectively inhibits the disintegration of substrate; SAP increases the effective moisture content of substrate and reduces its saturated permeability coefficient. ④ The influence degree of functional materials on the cohesion, disintegration resistance and permeability of substrate is consistent, which are guar gum, wood fiber, and SAP in the descending order. [ABSTRACT FROM AUTHOR]

The runoff volume capture ratio is the primary indicator of sponge city planning. The design rainfall corresponding to the runoff volume capture ratio is very important for the sponge city planning. Based on the 30-year hydrological rainfall data of 39 cities (include Shennongjia Forestry District) in Hubei Province, the relationship between the design rainfall and the runoff volume capture ratio in Hubei Province was analyzed, and the annual runoff volume capture target and the regional division for total rainfall runoff volume capture target of cities were formed, which filled the gap in the annual total runoff control index of cities in Hubei. The relevant value suggestions will contribute to the planning and construction of sponge cities in the Province. The results showed that the runoff volume capture ratio was divided into three zones, corresponding to Zone II (80%≤α≤85%), Zone III (75%≤α≤85%) and Zone IV (70%≤α≤85%) respectively, and the design rainfall ranges were Zone II (10 mm≤H≤28.3 mm), Zone III (12.7 mm≤H≤39.5 mm), Zone IV (14.3 mm≤H≤49.0 mm) respectively. Shennongjia, Danjiangkou, Shiyan etc. are in Zone II, and 17 areas such as Xiangyang, Lichuan, Xuan' en etc. are in Zone III, Suizhou, Tianmen, Xianning, Huangshi, Xiaogan, Xiantao, Huanggang, Ezhou, Wuhan and other regions are in Zone IV. [ABSTRACT FROM AUTHOR]

The project titled"Scientific Investigation of Water Resources Development Potential and Utilization Pathways on the northern Slope of the Kunlun Mountains"was initiated in October 2021 as part of the initial set of projects for the Third Xinjiang Scientific Expedition. This study integrates multi- source remote sensing data and field research conducted from 2022 to 2023 to examine hydrological changes, water resources dynamics, and water resource utilization patterns on the northern slope of the Kunlun Mountains. The findings reveal the following: (1) A temperature increase of 0.14 °C·(10a)-1 and precipitation increase of 6.53 mm·(10a)-1 from 1990 to 2020 was observed on the northern slope of the Kunlun Mountains. (2) Glacier variations have remained relatively stable, with a slight expansion observed in snow cover area and depth. (3) Permanent water bodies have experienced a significant growth rate of 79.89%, while seasonal water bodies have expanded by an impressive margin of 144.49%. (4) Ayakkum Lake and Akikkule Lake, two major lakes within the Kumukuli Basin, witnessed increases in their water areas by approximately 68.91% and 58.22%, respectively, and several rivers within this basin exhibit potential for further development regarding water resources utilization. (5) Terrestrial water storage on the northern slope of the Kunlun Mountains generally exhibits an increasing trend, particularly more pronounced from west to east. (6) Average annual runoff of Hotan River, Keriya River, and Qarqan River, the main rivers on the northern slope of the Kunlun Mountains, increased by 20.24%, 27.85%, and 45.17%, respectively, during the period of 2010--2023 when compared with the period of 1957--2023. (7) Based on simulations considering different climate change scenarios, it is predicted that major river runoff will continue to increase throughout the middle-to-later stages of the 21st century, alongside regional augmentation in available water resources. The conditions of water resources on the northern slope of the Kunlun Mountains can provide favorable water resources for the green development of the region. [ABSTRACT FROM AUTHOR]

Lake-terminating glaciers are widely distributed in the Himalayas, and their rapid melting and terminal calving are the most significant triggering and influencing factors of glacial lake outburst floods in the region. In recent years, the lake- terminating glaciers have experienced continuous and accelerating mass loss. From 1975 to 2000, the mass loss of lake- terminating glaciers was -0.33 ± 0.07 m w.e. ·a-1. In the past 10 years, it has reached -0.56±0.08 m w.e.·a-1, and its average mass loss rate was -0.45±0.08 m w.e.·a-1. The mass loss rate of lake-terminating glaciers is significantly higher than that of others, and terminal melting and calving are the primary reasons. The subaqueous mass loss of lake- terminating glaciers terminus cannot be accurately estimated. The plume model is widely used to simulate the melting of tidewater glaciers, providing a feasible method for determining the lake-ice mass/heat exchange process at the lake-terminating glaciers terminus. The amount of subglacial meltwater runoff, the cross-section shape of the glacier terminal, and the temperature and density of lake water significantly affect the estimation results of the plume model. Evaluating the underwater melting characteristics of glacier terminals based on the plume model will lay the foundation for accurately estimating future glacier mass changes. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The aims of this study are to examine the influence of forest vegetation changes on water-sediment dynamics, and to provide a scientific basis for formulating and adjusting ecological environment development policies in the Yellow River Basin. [Methods] Based on the runoff and sediment discharge data from the Dacun hydrological station in the Shiwangchuan River Basin from 1959 to 2018, as well as precipitation data within the basin, the hydrological changes over a span of 60 years were analyzed. By combining NDVI data from 1985 to 2018 and land use data from five periods, the vegetation underlying surface driving effects on water-sediment changes in the watershed were analyzed and discussed. [Results] The runoff and sediment discharge in the Shiwangchuan River Basin had shown a significant decreasing trend over the past 60 years（p＜0.01）, with abrupt changes occurring in 1988 and 1983, respectively. However, there had been no significant trends in land use and precipitation within the watershed during this period. The NDVI during the growing season showed little variation before 2000 but exhibited a significant increasing trend after 2000. [Conclusion] Before 2000, the implementation of various soil and water conservation measures was the main reason for the decrease of runoff and sediment transport in the basin; After entering the 21st century, the improvement of vegetation quality in the basin has further reduced runoff and sediment transport. [ABSTRACT FROM AUTHOR]

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Copyright of Arid Zone Research / Ganhanqu Yanjiu is the property of Arid Zone Research Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] Simulating the change of runoff and sediment changes in the watershed under the influence of land use and climate in the future is conducive to making suitable management plans. [Methods] Based on land use and meteorological data, combined with CMIP6 climate model data, PLUS model and SWAT model, the temporal and spatial changes of land use and runoff and sediment under different climate scenarios in 2030 were quantitatively simulated. [Results] (1) The SWAT model exhibited good accuracy in monthly scale in simulation of Minjiang River Basin, in which the R2 and NSE (Nash-Sutcliffe Efficiency) ranged from 0.80 to 0.95 and 0.75 to 0.91, respectively. The R2 and NSE ranged from 0.75 to 0.98 and 0.64 to 0.94 respectively. (2) Using the land use data of 2020 to evaluate the accuracy of the PLUS model, the Kappa coefficient was 0.77, and the simulated construction land and cultivated land in the Minjiang River Basin in 2030 would increase by 325.64 km2 and 1 157.51 km2, respectively. (3) Under the SSP2-4.5 and SSP5-8.5 scenarios, the average precipitation in 2025—2035 would increase by 0.15% and 2.18%, and the average annual temperature would increase by 0.23 and 0.62 ℃, respectively. (4) In the low carbon and high carbon scenarios, only land use change led to an increase of 0.08% and 0.07% in annual mean runoff, and an increase of 0.24% and decreased of 0.05% in annual mean sediment transport, respectively, compared with the baseline period. Compared with the baseline period, the mean annual runoff decreased by 4.76% and 4.11%, and the mean annual sediment transport increased by 18.12% and 0.13%, respectively. The combined effects of land use and climate resulted in a decrease of 4.57% and 3.93% in annual average runoff and an increase of 18.28% and 0.33% in annual average sediment transport compared with the base period, respectively. (5) Under the scenario of future climate and land use comprehensive change, the areas with higher and larger increase in surface runoff and sediment yield were concentrated in the northwestern of the basin centered on Shaowu City in Nanping and the southwest of the basin centered on Jiangle County in Sanming. [Conclusion] These research results provide some reference for the reasonable development and construction of Minjiang River basin in the future.

[Objective] To explore the effects of degradable mulch film mulching on runoff and loss of dissolved nitrogen and phosphorus. [Methods] Polyethylene film mulching (PF) with a thickness of 0.003 mm, degradable film mulching with a thickness of 0.006 mm (BF1), 0.008 mm (BF2), 0.010 mm (BF3) and 0.012 mm (BF4), and no mulch (CK) were set up. In in-situ runoff plots, using mulching on ridge tillage peanut planting as the study object, the runoff and concentration of ammonium nitrogen (NH4+—N), nitrate nitrogen (NO3-—N), and available phosphorus (PO43-—P) in runoff under natural rainfall conditions were measured, and the runoff and nutrient loss characteristics under different thickness of degradable mulch film were analyzed. [Results] (1) The degradation time of degradable film increased with the increase of film thickness. (2) The order of cumulative runoff was BF1

Underlying surface has led to the complex hydrological response of watersheds in small mountainous areas. Among them, the slope can be the basic unit of hydrological response. It is of great significance to explore the hydrodynamic features of runoff under different conditions of underlying surface on mountainous slopes. In this study, the underlying surface of the slope was selected in the typical mountain areas, the Guanshan River watershed. Multiple simulated rainfall experiments were conducted in the laboratory. A systematic investigation was made to clarify the runoff and erosion hydrodynamic features of the soil slope under different slope gradients, soil thickness distribution, and soil base permeability. The results showed that: 1) The Reynolds number, shear stress, and runoff power increased with the increase of rainfall intensity, whereas, the DarcyWeisbach resistance coefficient decreased. The rain intensity initiated a significant increase in the mean values of Reynolds number and runoff power (P<0.05). The mean values of Reynolds number and runoff power at the rain intensity of 60, 90, and 120 mm/h increased by 130%-435%, compared with the mean values of 30 mm/h. Slope gradients shared significant positive effects on the mean shear stress and mean runoff power (P<0.05). The mean shear stress for the 15 and 25 slope gradients treatments increased 135% and 187%, respectively, compared with the 5 slope gradients treatment; The mean runoff power increased 224% and 357%, respectively. The thickness of the soil layer had significant effects on the mean Darcy-Weisbach resistance coefficient, mean Reynolds number and mean runoff power under a permeable soil base. The permeability of the soil base also exhibited a significant effect on the mean Reynolds number and the mean shear stress, when the thickness of the soil layer was thin at the top. The hydrodynamic features depended mainly on the rainfall intensity. The variance contributions to the Reynolds number reached 83.11%. The dominant influencing factors on shear stress and runoff power were the rainfall intensity and slope gradients. The sum of both variance contributions to shear stress and runoff power reached 67.64%, and 80.58%, respectively. Slope and soil thickness were the main influencing factors on the hydrodynamic parameters under a single rainfall intensity, followed by the interactions between soil thickness and slope gradients. The bottom permeability and soil thickness also presented some influence on the hydrodynamic parameters. Therefore, it is very necessary to consider the soil bottom permeability, soil thickness, and their interaction on hydrodynamic features, rainfall intensity, and slope gradients. The findings can provide some theoretical support to determine the influence of runoff and sediment yields on the complex slope surface. Some parameters can also be offered to simulate the hydrological process in small mountainous watersheds. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Slope has an important effect on the runoff production process. Slope correction of runoff curve number in the SCS-CN runoff production model is important to improve the model prediction accuracy, In order to conduct an investigation of the effect of average watershed slope in the runoff production process, in this paper, based on Huang's slope modification formula, the first 40 out of 70 rainfall runoff measurements in the study area from 1955 to 1981 were used as the validation data, and a1 and a2 parameters in Huang's slope modification formula were re-determined, so as to propose the slope modification formula of the CN value for the study area under three different antecedent moisture conditions, and then the SCS-WJG method, which is of good applicability to the region, was established and compared to the SCS-CN look-up table method, and the SCS-Huang method, which is a direct transfer of the Huang's slope modification formula. The conclusion is as follows: the λ-value of the initial rainfall loss rate determined using the ergodic method is 0.09, so the standard value of 0.2 is not applicable to the study area. After comparing the size of the CN values obtained by the three methods, it is found that the CN value obtained by the SCS-Huang method is the largest, followed by the SCS-CN look-up table method, and the smallest is obtained by the SCS-WJG method, so the CN value obtained by the SCS-WJG method is more suitable for the study area as shown in the simulation results. Comparison of the SCS-CN lookup table method and the SCS-Huang method reveals that the NSE of the SCS-Huang method is lower and the RMSE is higher; therefore, it is necessary to propose a slope correction formula for the CN value applicable to the study area and establish the SCS-WJG method. When λ = 0.09, the NSE of the SCS-CN lookup table method, and the SCS-Huang method are -2.85 and -3.25, respectively, while the NSE of the SCS-WJG method is increased to 0.86, and the RMSE of the SCS-WJG method is reduced by 77%, and 78%, respectively, compared with the first two methods. The simulation accuracy of the SCS-WJG method is significantly better than that of the remaining two methods, indicating that the SCS-WJG method has good regional applicability and can provide a reference for the simulation of runoff production in small watersheds. [ABSTRACT FROM AUTHOR]

Based on the hydrometeorological data in half a month during the flood and dry seasons at four buoy stations in the inner Lingdingyang estuary, the tidal dynamics, runoff dynamics and other powers on average velocity during a tidal cycle had been discussed by introducing the algorithm of main tidal flux section and the binary linear regression method. It showed that average water depth velocity in half a month during the flood and dry seasons in the inner Lingdingyang waters is between 25-45 cm/s, with little difference between flood and dry seasons except at the West beach waters, where the average water depth velocity in the flood season is significantly greater than that in the dry season.. The coefficient a, which represented the contribution on velocities by tidal dynamic, was always positive, indicating that it is the main driving force for the reciprocating movement of the Lingdingyang estuary. The coefficient b representing runoff dynamic was negative at rising the tide stage and positive at the ebb tide stage during the flood season, showed that freshwater discharged into the Lingdingyang estuary by the east four mouths possessed a large initial momentum which strengthened the power of ebb current; while was negative irrespective of rising or falling current during dry season, showing that runoff dynamic was weak and diluted flux mainly moved with tidal current. The coefficient c by other dynamics during the flood and dry seasons was mainly related to density baroclinic gradient force caused by monsoon and salt water intrusion, and there was a good linear negative correlation with the coefficient b by flux of freshwater, more obvious during flood season. Applying incipient velocity of suspended sediment in the Lingdingyang estuary, combined with the fitting formula of average velocity at a tidal cycle obtained by the binary linear regression method, the concept of critical runoff was put forward, and the reason of the phenomenon of "beach scour channel siltation" existed in the Lingdingyang estuary was explained. The Lingdingyang estuary was in the state of sedimentation as a whole during the dry season with more significant during the rising tidal ohase. [ABSTRACT FROM AUTHOR]

[Objective] The aims of this study are to accurately predict the peak flow at small watershed scale, and to provide support for hydrological application and soil and water conservation assessment. [Methods] The data of 215 rainfall events from 2013 to 2021 were used to analyze effect factors of the peak flow in Liujiagou small watershed, Wanzhou County, Chongqing. The Pearson correlation analysis was performed between peak flow rate and effect factors, including runoff depth, runoff coefficient, rainfall depth, maximum 30-minute rainfall intensity(I30), and average rainfall intensity. A new peak flow rate equation was developed based on linear regression and nonlinear regression analysis to predict the peak flow rate for small watersheds in Chongqing. The first data set, including 172 storms, was used to develop a new formula for predicting peak flow rate. A second set of data, including 43 storm events, was used to test the new equation. [Results] The peak flow rate was significantly correlated with rainfall, I30, runoff depth, and runoff coefficient at the 0.01 confidence level. The model efficiency was 0.85 and 0.82 when 172 and 43 rainfall events were used, respectively. [Conclusion] The new equation can provide good accuracy in the small watershed in Chongqing. The new equation will be helpful for the decision-making of soil and water conservation measures, the design of soil and water conservation engineering facilities and the evaluation of soil erosion in Chongqing and even the small watersheds in southwest China. [ABSTRACT FROM AUTHOR]

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Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Influenced by the distribution of karst landforms and karst development, the process of rainfall runoff in karst regions is complicated. Runoff simulation can help identify the main factors influencing runoff in karst areas. In this study, based on the karst landform characteristics of the small watershed of the Mudong River in Huixian Karst Wetland in the Lijiang River basin, parallel staggered time model of double tanks was established and an artificial neural network was built by using Microsoft Excel for parameter optimization. The relative error, the Nash-Sutcliffe efficiency coefficient and the correlation coefficient were used to evaluate the simulation effects during calibration and validation based on the measured discharges in the small watersheds. The mean annual relative error of the regularization rate was 7.5%, the Nash-Sutcliffe coefficient was 0.63 and the correlation coefficient was 0.72. During the validation period, the mean annual relative error was 10.5%, the Nash-Sutcliffe coefficient was 0.56 and the correlation coefficient was 0.63, indicating that the model was able to achieve good simulation results in the study area. Through the parameter sensitivity analysis of the runoff simulation of the Tank model in the small watershed of Mudong River, the results show that the karst geomorphological characteristics such as surface infiltration performance, the existence of karst fast flow and slow flow, and karst base flow mainly affect the runoff distribution and production flow in the karst small watershed. [ABSTRACT FROM AUTHOR]

A vegetation buffer strip is an important spatial barrier in rivers and lakes. It is used to alleviate the direct interference of human activities on rivers and lakes and block agricultural nonpoint source pollution. Eight buffer strips were designed in a small watershed Dingyuan in Zhangshan to systematically study the effect of interception provided by different types of buffer strips on pollutants such as N and P in farmland. Combined with natural rainfall methods, the reduction effects of different buffer strips on surface runoff and its main pollutants such as total N (TN), total P (TP), and chemical oxygen demand (COD) were observed for two years. The results showed that forest land and 3° and 8° cross-ridge tillage buffer had the highest runoff interception efficiency, with interception rates of 62.4%, 52.0%, and 60.6% for TN, TP, and COD, respectively. The runoff increased first and then decreased with the increase of rainfall intensity. Compared with the 8° slope treatment, the sediment reduction rates of the cultivated land buffer zone in the downhill (3°) treatment for vertical ridge and cross-ridge were 53.3% and 50.9%. The nutrient loss of rainfall runoff on the slope was mainly composed of N and organic matter, the average interception rate of NH+4-N in the runoff was as high as 95.2%. All buffer strips had good retention effect on TP in the runoff, and the loss of CODMn on the slope of 3° and 8° cross-ridge cultivation was the lowest, and the interception rate reached 53.0% and 58.6%. Our results indicated that the presence of high coverage vegetation and developed roots in the forest buffer strip can effectively slow down the erosion caused by rainfall on the surface and reduce runoff and nutrient loss. The implementation of cross-ridge cultivation in rural hilly and mountainous areas in the south is also an effective measure to retain runoff and reduce the risk of nonpoint source pollution. [ABSTRACT FROM AUTHOR]