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Most previous studies focused on farmers' awareness of soil and water conservation and technology, but ignored the importance of public awareness of soil and water conservation. In this study, a survey was conducted in 10 provinces with varying degrees of soil and water loss in China, and 1021 valid samples were obtained. Data were analyzed in SPSS 24.0 with independent sample t-tests, correlation analysis and regression analysis. The final results are as follows: in terms of soil and water loss, compared to those in the less serious region, participants in the serious region had a higher score on knowledge and perceived importance, and a more positive evaluation of future development of SWC and stronger intention to act as a supporter for SWC. However, there were no significant differences in evaluation of the major of SWC between less serious and serious regions. In addition, participants' knowledge had a positive impact on behavioral intention. The perceived importance, major recognition and participants' evaluation of future development mediated the relationship between participants' knowledge about water loss and soil erosion and their behavior intention. For informatization in SWC, there were no differences between the serious region and less serious region regarding participants' evaluation of intuitiveness, accuracy, affordability, and easiness. Furthermore, participants in the less serious region had a more positive evaluation for timeliness of informatization of soil and water conservation than those in the serious region. [ABSTRACT FROM AUTHOR]

There is a lack of information available on the in situ extreme rainfall storms-induced hydrological and sedimentological dynamics of conservation tillage-based agro-geotextiles (AGTs) system. In the present field study on a conservation tilled maize crop planted on 4% natural runoff gauging plots (100 × 20 m2), we investigated the effect of indigenously prepared need-based AGTs from giant-reed (Arundo donax) and maize (Zea mays L.) stover; synthetically prepared coir-geo-textile; vegetative barriers of cowpea (Vigna unguiculata) and grass-weed and only conservation tilled maize crop as a control treatment. Surface runoff and soil erosion processes from 36 runoff causing events in relation to the maize growing stages under different treatments were analyzed. During five extreme rainfall events (>100 mm), which occurred in the most sensitive period of soil erosion, AGT prepared from Arundo donax maintained the highest runoff reduction effectiveness ∼29–75% and erosion reduction effectiveness∼24–94%. Overall, the AGTs system lost only 6–8% of rainfall as runoff and 1–4 t ha−1 yr−1 of soil from all the storms in comparison with the only conservation tilled maize fields which lost 24% of rainfall as runoff and 17.3 t ha−1 yr−1 of soil. The same treatment also maintained the lowest peak intensity of runoff water i.e., 0.018 cm h−1; and longest time to attain the peak intensity of runoff water i.e., 0.795 min. Minimum rainfall required to initiate runoff (0.1 mm) was 18.5 mm in only conservation tilled maize while it was 40.5 mm in AGT prepared from Arundo donax. Key findings from this study indicate that in the context of frequently occurring of extreme rainfall events in the future climate change scenario, indigenously prepared need-based AGTs from locally available perennial grass like Arundo donax or other similar vegetation can successfully replace a conventional system of permanent vegetative barriers and synthetic coir-geo-textiles on sloping arable croplands of Indian Himalayan Region (IHR) and other similar locations of the world. [Display omitted] • Six storms of more than 100 mm shared 34% of the total rainfall (2472 mm). • Highest sediment concentration in runoff was recorded in first runoff causing event. • Highest soil loss was recorded in V 0 –V 7 stages of maize. • Agro-geotextiles (AGT) of Arundo donax reduced runoff 29–75% during extreme events. • Studied AGTs offer a practical alternative to the permanent vegetative barriers. [ABSTRACT FROM AUTHOR]

With the increase of investment in soil and water conservation in China, its implementation has attracted much attention. There have been studies on soil erosion control and economic loss in previous studies, but the performance of soil and water conservation has rarely been evaluated by stochastic frontier function model. Based on the stochastic frontier function model and considering the change of local environmental managers, this study combined with the data of soil and water statistics to conduct time series analysis, and found that the environmental management under the pressure of promotion will improve the efficiency of water and land resources management. [ABSTRACT FROM AUTHOR]

The magnitude and variation of the sediment loads transported by rivers have important implications for the functioning of river systems and changes in the sediment loads of rivers are driven by numerous factors. In this paper, the key drivers of changes in the sediment loads of the major rivers of China are identified by reviewing recent studies of changes in their sediment loads. Except for the Songhua River, which presents no clear tendency of change in runoff or sediment load, nearly all the major rivers of China are characterized by an apparent decline in annual sediment load. The total annual sediment load of major Chinese rivers transported to the coast decreased from 2.03 billion t/yr during the period 1955–1968 to 0.50 billion t/yr during the period 1997–2010. The primary drivers of changes in the sediment loads of the rivers are dam construction, implementation of soil and water conservation measures, catchment disturbance, agricultural practices, sand mining and climate change. Examples drawn from Chinese rivers are used to demonstrate the importance of these drivers. Construction of a large number of reservoirs in the Yangtze River basin represents the primary driver for the reduced sediment load of the Yangtze River. The implementation of soil and water conservation programmes is one of the key drivers for the sharp decline in the sediment load of the Yellow River. Catchment disturbance explains why the reduction of the sediment load of the Lancang-Mekong River at the Chiang Saen gauging station was much less than that at the Gajiu gauging station upstream. A reduction in sediment load resulting from the expansion of agricultural production may be the main driver for the reduced sediment load of the Huaihe River. The decrease in the sediment load of the Pearl River has been influenced by sand mining activities. Climate change is one of the key drivers responsible for the greatly reduced sediment load of the rivers in the Haihe River Basin. [ABSTRACT FROM AUTHOR]

Aiming at soil and water conservation and geological relic landscape based on GIS, it can effectively enhance the real-time and sharing of soil and water conservation data, and present the content of soil and water conservation data in a more intuitive and reasonable way. An open source geospatial database based on the combination of PostgreSQL and PostGIS from the perspective of visualization of soil and water conservation big data. With the support of D3 for geographic operation and visualization, a complex composite map is realized, which fully reflects the spatial characteristics of soil and water conservation data and the accuracy of comprehensive results. It has been proved that the application of spatial operation methods provided by PostGIS in visualization of soil and water conservation transfers a large number of complex operations such as calculation and transformation to the database layer, which reduces the complexity of the system, reduces the dependence of the system on various commercial or open source geographic service tools, and ensures the lightweight of the system itself. [ABSTRACT FROM AUTHOR]

Developing and adopting strategies that preserve soil health from degradation due to drastic changes in climate is critical for securing sustainable viticulture. For example, healthy soils promote water infiltration, nutrient cycling, and retention functions that support grape production. However, little research has evaluated drivers of growers' decision-making processes and actions towards soil management practices that impact soil health in vineyards. The objective of this study was to assess wine grape growers' perceptions and attitudes of soil health to identify grower's most important soil health functions and definition, and to understand how these might influence behavior related to soil management practices. Therefore, we conducted semi-structured interviews with 16 wine grape growers understand current barriers, motivations, and opportunities for adopting and/or maintaining practices for building soil health in vineyards. Most growers described healthy vineyard soils as balanced, biodiverse, self-sustaining, and resilient systems that provide nutrient, and water cycling functions and support high-quality wine grape production. Three categories of growers emerged based on soil health attitudes including Early Adopter (n = 3), Early Majority (n = 4) and Late Majority (n = 9) groups. The main barriers for adoption and maintenance of soil health practices were high costs, potential economic risks, and lack of information on how these practices influence grape production especially for the Late Majority group. Most growers were willing to adopt more soil heath practices if additional specific, practical information could be provided on outcomes of soil health practices for wine grape production systems—especially economic benefits. The outcomes of this study guide future soil health research and outreach activities to better support growers in building and protecting vineyard soil health while achieving viticultural goals. • Semi-structured interviews were conducted to assess wine grape growers' perceptions and attitudes towards soil health. • Healthy soils were perceived as balanced, self-sustaining, and resilient systems supporting high-quality grape production. • Three grower categories emerged based on soil health attitudes: Early Adopter, Early Majority, and Late Majority groups. • High costs, economic risks, and lack of information were the main challenges for the adoption of soil health practices. [ABSTRACT FROM AUTHOR]

Plant available soil moisture and its spatial variability is among the most important limiting factors for crop and livestock productivity in semi-arid Ethiopia. The objectives of this study were therefore: 1) to measure the effects of land use and slope gradient on spatial variability of topsoil moisture content. 2) to analyze the variability of topsoil moisture content and crop responses under different soil and water conservation (SWC) structures and 3) to analyze whether topsoil moisture content, grain and biomass yields vary in relation to SWC structures. In total, 21 large runoff plots (600–1000 m2) were installed and treated with stone bunds, trenches, stone bunds with trenches and a control plot at each site. Plot sites were located on gentle (5%), medium (12%) and steep (16%) slopes of cropland and rangeland. Topsoil (0–15 cm) moisture content for plots were monitored daily using soil moisture probes (Theta-Probes) and weekly using manual sampling over two growing seasons. Crop performance was monitored during two growing seasons and grain and biomass yield were measured at harvest. Results show that average gravimetric moisture content of the topsoil during growing seasons is remarkably higher for cropland (33–25 g/100 g) compared to rangelands (24–20 g/100 g). This is due to tillage-induced runoff retention and infiltration. Soil moisture content decreases with increasing slope gradients, owing to increased drainage. Considering the effects of SWC structures, average topsoil moisture contents at accumulation and erosion zones are generally higher as compared to middle zone between two successive SWC structures. Average seasonal volumetric soil moisture content of 38.2 (cm3/100 cm3) in 2011 and 39.4 (cm3/100 cm3) in 2012 for accumulation zone of plots with stone bunds with trenchers are significantly higher than at other sampling locations. Crop growth performance, grain and biomass yield varied among plots and depended on slope gradients and SWC structures. Grain yields of wheat in 2011 and barley in 2012 were significantly higher for plots with SWC structures as compared to control plots and are highly correlated to topsoil moisture content (r = 0.64; p < 0.04 in 2011 and r = 0.59, p < 0.01 in 2012). Even when taking into account the cropland area occupied by SWC structures, grain yield increased by (4.2%−33%) for plots with SWC structures as compared to control plots. Overall, our results show that implemented measures may not only reduce runoff and soil loss, but also increase crop productivity by enhancing soil moisture and thus can significantly contribute to sustainability of agro-ecosystems in semi-arid environments. • Spatial distribution of topsoil moisture is related to land use and slope gradient. • Topsoil moisture content varies within plot due to water conservation structures. • Soil moisture content is significantly higher for treated compared to control plots. • Grain yield for both wheat and barley significantly correlated to topsoil moisture. • Soil and water conservation structures increased grain yield by (4.2 - 33%). [ABSTRACT FROM AUTHOR]

Abstract Soil erosion by water is a critical issue in the red soil regions of Southern China. Particularly, Changting County experiences severe erosion due to unreasonable human activities, high rainfall intensities, steep slopes, erodible parent material, and poor vegetation cover. In this study, a quantitative soil loss analysis and qualitative social surveys (data from 1999 to 2015) are integrated to identify the erosion vulnerable areas in Zhuxi watershed of Southern China. Using Zhuxi watershed as an example in the investigation of soil erosion problems, analytic hierarchy and entropy value methods are adopted to evaluate soil erosion vulnerability and determine the proportions of factors in an index system. The vulnerability of soil erosion is evaluated from the human–nature system coupling perspective, considering socio-economic factors, which are synthetically analyzed and evaluated for soil erosion exposure, sensitivity, and adaptive capacity. Results show that (1) vulnerability is low in the east and west and highest in the middle of the Zhuxi watershed. The vulnerability of low, mild, and moderate soil erosions show a patchy distribution, wide range of intensity, and severe soil erosion fragility. (2) The degree of soil erosion vulnerability gradually decreased from 1999 to 2015. Low levels of vulnerability were distributed from fragmentation to concentrated distribution, while high vulnerabilities presented the opposite trend. However, the high levels of soil erosion showed a gradual decrease in vulnerability from 1999 to 2015. This study provides important theoretical and practical information for constructing a safe soil erosion control and management system and accelerating the sustainable development of social economy in the watershed. Graphical abstract Spatial distribution of erosion evolution vulnerability grade in Zhuxi watershed from 1999 to 2015. Unlabelled Image Highlights • Soil erosion vulnerability is mainly used to predict the potential impacts and trends of soil erosion. • Soil erosion vulnerability is high in the middle part of the Zhuxi watershed and low in its eastern and western parts. • The vulnerability of soil erosion gradually decreased in 1999–2015. • The result is beneficial to identify and reduce the vulnerable areas of soil erosion. [ABSTRACT FROM AUTHOR]

Abstract The future trend of water and sediment variation is closely related to the governance of the Yellow River. The increasingly frequent occurrence of extreme rainfall events has rendered the future water and sediment situation of the Yellow River uncertain. Understanding the characteristics of flood and sediment yield of the river basin under extreme rainfall conditions at different times is a prerequisite and foundation for accurate prediction of water and sediment situation in the Yellow River in the future period. We here used the July 26 extraordinary rainstorm event in 2017 in the Wuding River as a starting point for revealing the law of flood and sediment yields changes under extreme rainfall conditions around the year 2000. The results indicated that, during the period from 1960 to 2016, the average proportion of extreme rainfall depth in the middle Yellow River region over the total precipitation depth increased by 5.1%. Areas where extreme rainfall events frequently occur showed a trend of developing from localized regions in the Toudaoguai–Longmen reach to the majority of the middle reaches. There were obvious changes in the rainfall-flood and rainfall-sediment relations under extreme rainfall conditions. Compared with historical extreme rainfall events, the decline in flood and sediment yield in the river basin after 2000 under similar rainfall and intensity conditions was obvious. Among these results, flood decreased by 30.4–78.2%, sediment yield was decreased by 53.0–88.2% and sediment content in flood was decreased by >47.2% on average when compared with the same rainfall conditions in the previous century. Comparative watershed studies showed that, during extreme rainfall events, areas under soil and water loss management programs suffer 57.2% and 75.7% less flood runoff modulus and sediment transport modulus, respectively, than non-managed areas. This indicates that soil and water loss management is the major driving factor for changes in rainfall-flood and rainfall-sediment relations under extreme rainfall conditions. This study highlights the importance of soil and water loss management in the flood control and sediment reduction. We concluded that, with the implementation of soil and water conservation measures, the probability of large flood and sediment events will greatly decrease and the amount of sediment entering the Yellow River under extreme rainfall will further decrease in the next 30 years. Highlights • Frequency of extreme rainstorm events in the Yellow River increased significantly. • Rainstorm-sediment relations exhibited obvious changes after 2000. • Soil and water loess management plays a key role in reducing sediment. • The probability of large flood and sediment events will greatly decrease. [ABSTRACT FROM AUTHOR]

Highlights • Choice experiment on farmers' preferences for payment for ecosystem services. • High willingness to accept PES contracts among farmers in Eastern Uganda. • Preference heterogeneity related to farm size, poverty and food security. • Land-constrained farmers very reluctant to adopt strict river bank demarcation. • Targeting and individual compensation increases cost-effectiveness in PES schemes. Abstract Payments for ecosystem services (PES) is a market based policy tool that is increasingly being recommended for effective and sustainable management of watersheds, especially for Sub-Saharan Africa, where soil and watershed degradation are currently very severe. The design of PES projects is challenging and insights in the local context are indispensable. Using a choice experiment, this study investigates the perspective of farmers on the design of a PES program in the Mount Elgon region in Uganda. We use mixed logit and latent class models to reveal and explain preference heterogeneity for PES attributes. We calculate willingness to accept values and perform a cost analysis to identify the most cost-efficient PES programs. Our results point to a strong willingness of farmers to participate in a PES contract. The majority of farmers are willing to adopt different conservation measures, even in absence of a compensation; a minority of farmers are strongly averse to buffer strips along the river and do require a significant compensation. We find that farmers have strong preferences for individual over communal compensation, and that additional in-kind rewards in the form of labour assistance or tools increase the willingness to accept a contract. The findings imply that PES is a promising avenue for improved watershed conservation in the Mount Elgon region; and that individual compensation, differentiation and specific targeting of such programs may benefit their cost effectiveness. [ABSTRACT FROM AUTHOR]

Abstract The interactions between precipitation, runoff and sedimentation could reveal information about the processes of runoff and sediment production and the environmental evolution mechanisms of basins. Based on the hydrometeorological data collected over a long-term time series (1955–2012) which has been divided into five periods (P1 (1956–1969), P2 (1970–1979), P3 (1980–1989), P4 (1990–1999) and P5 (2000−2012)), changes and implications of the relationships between precipitation, runoff and sediment load (precipitation-runoff-sediment relationships) were studied in the Wuding River basin, China. Conclusions are as follows. (1) There is no obvious change occurs on the distribution of annual precipitation during 1955 to 2012. However, the annual runoff and sediment load are significantly decreased by 51.9% and 86.4%, respectively, from P1 to P5. (2) Under the same precipitation conditions, the runoff and sediment present overall decreasing trends. Decrease in the runoff was greater than that in the sediment load. The incoming sediment coefficient (ISC) reduced by 69.2%, indicating that the sediment transport ability per unit runoff was weakened. The significant reduction of ISC along with the decrease of the runoff amount caused the sediment brought into the Yellow River (STWY) decreased from P1 to P5. (3) Soil conservation measures played a critical role for the changes in precipitation-runoff-sediment relationships. Due to the rapid increases in the available storage of check dams in P2 and P5 and the areas of forest and grassland in P2, relationships among the precipitation, runoff and sediment has drastically changed. Decrease of the effects on sediment interception in check dams caused the sediment increased from P3 to P4. (4) Decreases of runoff and sediment load, and changes in their relationships would continue with the sustainable management of slopes and gullies. The potentially detrimental changes in the storage of check dams and those in runoff and sediment influenced by extreme weather conditions should be monitored and managed. Highlights • The annual runoff and sediment load have shown significant decreases (P < 0.05). • Human activities are the main driving factor of the changes in these relationships. • The decreasing effects of intercepting sediment led to the sediment increase in P4. • The STWY decreased because of the decreases in the ISC and runoff amount. • Changes in runoff and sediment under extreme weather should be considered. [ABSTRACT FROM AUTHOR]

• InVEST models would be more appropriate to address the fragile ecology issues. • Generalised Estimation Equations are used to modeling roadside ecological risks. • Road attributes and natural factors jointly influence ecosystem services. • Road grade, structure, rainfall, and topography are critical for ecosystem services. • Bridges or tunnels are recommended for ecologically sensitive areas. To explore the cumulative ecological effects of roads in ecologically fragile areas, the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) tool was applied to assess the spatiotemporal changes in habitat quality, water yield, and soil erosion in road-effect zones of the Western Sichuan Plateau, China. Then, generalized estimating equations were formulated to analyze the impact of synergies among road attributes, climate, topography, land cover, and other factors on ecosystem service changes. The results showed that the habitat quality within the road-effect zones was mostly affected by road grade and structure, and water yield and soil erosion were attributed to the factors of road structure, rainfall, and topography. Roadbed sections had the greatest negative impact on ecosystem services, followed by bridge sections and tunnel sections. Overall, the results of this study address habitat encroachment and soil and water loss in ecologically fragile areas, contributing to knowledge on green infrastructure planning. [ABSTRACT FROM AUTHOR]

• The SES framework and the ES evaluation methods are jointly employed. • Farmers creatively utilize traditional knowledge and develop nature-based solutions. • Landscape restructuring lays a foundation for soil and water conservation. • Stone terraced fields have a higher capacity for soil and water conservation. • Traditional knowledge correlates and interacts across scales. To explore how traditional knowledge acts in the soil and water conservation in mountain agricultural systems, this study selects the Shexian Dryland Stone Terraced System (SDSTS) as the study area and employs the social-ecological system (SES) framework and ecosystem service (ES) evaluation methods in a joint way. Results of the action mechanism analysis show that local farmers, as the main actors, fully utilize a variety of traditional knowledge, which constitutes a set of action situations at both the field and landscape scales. This has not only improved the soil and water conservation capacity of the SDSTS, but also met the livelihood need of the local people. Evaluation of the action outcomes further displays that the stone terraced fields have a higher capacity for soil and water conservation than other land use types and they also show a superior performance in food production. This has led to the highest comprehensive benefit per unit area found in the stone terraced fields (1.69 × 104 dollars·ha−1), much higher than forests (3.48 × 103 dollars·ha−1) and the grasslands (2.58 × 103 dollars·ha−1) on slopes. The traditional knowledge is proven extremely important for the SDSTS to achieve sustainable development and effective measures are thus needed to promote its inheritance and development. The combination of these two methods makes up for the shortcomings of the current traditional knowledge research, which mainly focuses on qualitative description and is lack of systematic explanation of mechanisms. The con-joint use of them also provides theoretical reference and technical support for more case studies of traditional knowledge in the future. [ABSTRACT FROM AUTHOR]

Soil erosion is a significant problem in rain-fed areas in India. This study attempts to evaluate the causal effects of on-farm soil and water conservation (SWC) measures on farm profit and yield. The study uses the inverse-probability-weighted regression adjustment (IPWRA) method to assess the causal impact of SWC measures on agriculture output while controlling socioeconomic, institutional, and village-level characteristics. The results suggest a significant difference in overall agricultural profit, crop-wise profit, and crop-wise yields among the adopters and non-adopters of the SWC measures. The study highlights that there is a complementarity between the causal impact of community-level SWC measures and individual SWC measures on agricultural outcomes. Further, the neighbor's adoption of SWC measures plays a pivotal role on farmer's agricultural profits. The study highlights that farmer's profit for rainfed crops such as maize further increases if their adjacent neighbors also undertake SWC measures. Such complementary effects, however, are not observed in case of irrigated crops such as paddy. • This study measures the impact of soil and water conservation (SWC) measures on agricultural outcomes. • SWC measures undertaken by the neighbors have significant positive spill over effects. • Community level conservation measures complement farmer's own SWC measures. • The SWC practices are more suitable and have significant impact on rainfed crops. [ABSTRACT FROM AUTHOR]

• Stone terrace walls regulate fluvial processes and decrease hydraulic connectivity. • A. ramosus clones are strongly spatially associated with stone terrace walls. • Highest frequency of A. ramosus clones is in the terrace walls' upstream side. • Terrace walls provide better habitat conditions compared to inter-wall spaces. Ancient stone terrace walls aimed at harvesting water runoff and facilitating crop production are widespread across the drylands of the Middle East and beyond. In addition to retaining the scarce water resource, the terrace walls also conserve soil and thicken its profile along ephemeral stream channels (wadis) by decreasing fluvial connectivity and mitigating erosional processes. In this study, we created hydrological models for three wadis with ancient stone terrace walls in the arid northern Negev of Israel, where the predominant geophyte species is Asphodelus ramosus L. A two-dimensional (2D) rain-on-grid (RoG) approach with a resolution of 2 m was used to simulate the rain events with return periods of 10, 20, 50, and 99 % (10-y, 5-y, 2-y, and yearly, respectively) based on the Intensity-Duration-Frequency rain curves for the region. To evaluate the effect of stone terrace walls on fluvial hydrology and geomorphology, the ground level was artificially elevated by 20 cm at the wall locations in a digital terrain model (DTM), using the built-in HEC-RAS 2D terrain modification tool. Our results showed that the terraced wadis have a high capacity to mitigate runoff loss, but a lesser capacity to delay the peak flow. Yet, for all rainstorm return periods, peak flow mitigation was positively related to the number of terrace walls along the stream channel. Field surveys in two of the studied wadis demonstrated that the A. ramosus clones were found in proximity to the stone terrace walls, presumably due to the greater soil–water content there. The results thus suggest that the terrace walls provide improved habitat conditions for these geophytes, supporting their growth and regulating their distribution along the wadi beds. [ABSTRACT FROM AUTHOR]

• Terrace changes and its ESs across diverse landforms for an extended duration were explored. • 81.34 % of Gansu's counties feature terraced fields, mainly in hilly and gully areas. • Terraces change were characterized by significant spatiotemporal heterogeneity. • Terraces conserved 1.82 × 109 t soil and 2.36 × 1010 m3 water. • Terraces increased ESV by 815.10 million $, mainly in regulating services. The exploration of terrace change and its associated ecosystem services (ESs) provides invaluable insights into the intricate interplay between engineering initiatives and environmental conditions. This understanding is crucial in designing strategic plans for environmental management. However, how terraced fields area change and influence ESs over an extended period at a regional scale remain relatively unknown. To bridge this knowledge gap, this study focused on terraces in Gansu Province (a typical inland mountain province), Northwestern China, by dividing the study area into seven regions, the quality and value benefits of unit area, the overall and cumulative of terraces were calculated for each region in Gansu province based on remote-sensing data, meteorological data, terraced area and benefits data. In this regard, the distribution, spatiotemporal changes and ESs associated with terraced fields in Gansu were examined from 1990 to 2020. The results show that: (i) terraces with the area of 2.20 × 104 km2 accounts for 81.34 % of counties(districts) of Gansu province in 2020, mainly located in the loess hilly and gully region (82.72 %). (ii) From 1990 to 2020, the terrace area in Gansu expanded from 8.13 × 103 to 2.20 × 104 km2, peaking at 636.73 km2/yr during 1990–2000, with notable spatial heterogeneity. (iii) In terms of ESs' quality benefits, soil conservation benefits of terraces were the most significant, reaching 91.30–98.32 % per unit area, the cumulative benefits (1990–2020) were 1.82 × 109 t, followed by water conservation benefits (42.12–89.20 % and 2.36 × 1010 m3). (iv) Terraces expansion have increased the ecosystem service value by 815.10 million Dollar ($), with regulating services and habitat services accounting for 34.92 % and 31.92 %, respectively. These results indicate that the enormous potential value of terraces in ecological environment governance and ecological economic benefits, and provide a scientific support for understanding terraces and leveraging their ecosystem functions, while also offering valuable insights for the conservation of global mountain ecosystems and the improvement of human well-being. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil and Water Conservation Practices (SWCPs) reduce short-term soil loss. • The long-term effect of many SWCPs is questionable, especially in humid regions. • Forestation is effective; gully sediment losses negate upstream SWCP benefits. • Watershed simulations of SWCP overestimate the decrease in offsite soil loss. • SWCPs should also be evaluated by long-term experiments in catchments. Soil and water conservation have been traditionally part of farming practices for thousands of years. Despite massive efforts to implement modern soil and water conservation practices (SWCPs) in the Ethiopian Highlands, soil erosion increased after the 1970s when social and political events led to a remarkable change in land use. This review aims to critically analyze the impact of conservation practices on soil loss and crop yield and highlight research and modeling gaps. In doing so, 120 published articles on experimental and simulated soil losses in the Ethiopian Highlands were retrieved from the refereed literature. We found that most published experimental studies evaluating SWCPs lasted less than five years in areas of less than 100 ha. Most modeling studies were over short periods, too; some models simulated soil loss over large areas. The literature analysis for these short-term experimental studies showed that SWCP decreased soil loss on individual sites and increased crop yield in semi-arid regions. Simulated sediment concentration increased as a function of watershed size, while observed soil losses did not follow this trend. Moreover, the decrease in soil loss due to the soil and water conservation practices on small plots was also greatly overestimated. Consequently, past research and current modeling techniques are inconclusive on the effectiveness of SWCPs in large catchments over periods exceeding five years and those with active gullies. Additional long-term experimental studies in catchments are required to evaluate whether SWCPs can decrease sediment loads. [ABSTRACT FROM AUTHOR]

Soil erosion and accompanying sediment issues have a significant impact on environmental sustainability. However, there is not currently a clear understanding of the relationship between soil erosion and sediment sources at the catchment scale, which has led some researchers to regard areas with severe soil erosion as the main sediment source. This view does not apply in all circumstances. • This paper uses 137Cs to study the average annual erosion rate of different land use types. The results show that the erosion rates of woodland, sparse woodland and farmland areas were 400, 1756, and 2771 t·km−2·a−1, respectively, multiplied by the corresponding area. Surface soil erosion levels in the catchments of the three types accounted for 11%, 26% and 25%, respectively, and the total accounted for 62% when the gully bank accounted for 38%. • Fingerprinting technique results show that the relative source contributions of woodland, farmland, sparse woodland and gully bank areas to sediment at the small catchment outlet were 4%, 10%, 48% and 38%, respectively. The results reveal that the detachment process of soil and the transport process of sediment with runoff were internally related and independent of each other. • By comparing on-site erosion rates with downstream source contributions, we have a clearer understanding of soil erosion and subsequent sediment transport process in the agroforestry catchment in mountainous areas. We emphasize the importance of governance and management in areas with severe soil erosion, mainly targeting types such as hillslope framland. In addition, sparse woodland and gully banks should be given more attention, as they account for a large proportion of sediment in the downstream catchment. • Soil erosion using 137Cs based on multiple reference inventories. • Combine on-site erosion by 137Cs with sediment sources by fingerprinting. • Clearer understanding of soil erosion and sediment transport process. [ABSTRACT FROM AUTHOR]

Watershed management initiatives are designed to conserve essential soil, water, and vegetation resources while ensuring production and agricultural sustainability. As a result, assessing watershed management projects is a must for future executive planning and natural resource management. However, there has yet to be a quantitative performance evaluation of alternative watershed management techniques on the watershed's overall health. The current study used the pressure-state response (PSR) conceptual framework to assess watershed health in the current scenario and identify the related functional criteria and indicators at the sub-watershed level. Field surveys and reviews of available information were used to identify and characterize current watershed concerns and challenges. The PSR framework was used to assess the impact of conventional watershed management measures and a problem-oriented adaptive management strategy on watershed health in the Mikhsaz Watershed in northern Iran. The influence of changes in the contribution of the study criteria to the health and corresponding scenarios on modifying the watershed health was evaluated. A health index score of 0.68 revealed a healthy class in the current circumstances. The health index was somewhat enhanced after adding the typical or conventional measurements in the research area (i.e., 0.69). Adaptive management techniques in response to the identified issues improved the watershed's health index by 7.2% (i.e., 0.74) in a more efficient, technically acceptable, and ecologically benign manner. As a result, the adaptive management measure increased economic productivity by 61% compared to the conventional measures. The study's findings call for a global revival in watershed management policy, focusing on developing nations. [Display omitted] • The pressure-state-response framework (PSRF) was employed at the watershed scale. • The watershed health (WH) was assessed using PSRF under various policy scenarios. • The effect of conventional and adaptive management approaches on WH was compared. • Scenarios performance on WH was assessed in the Mikhsaz Watershed, Iran. • Adaptive management was economically (≈7%) and technically (≈61%) outperformed. [ABSTRACT FROM AUTHOR]

Abstract We assess whether a Payments for Ecosystem Services (PES) programme met its objectives of reducing soil erosion and yielding water in an environmental protected area, the Guariroba River Basin, Midwestern Brazil. We measured rainfall and water discharge throughout 2012 and 2016. During the same period, soil and water conservation practices were performed in the basin, such as: building level terraces and riparian vegetation recovery. We separated streamflow into baseflow and direct runoff, then we evaluted the baseflow index that indicated that groundwater significantly contributes to total flow. Therefore, to investigate the effects on streamflow, we performed a trend analysis in the baseflow time series using the Mann-Kendall test. In addition, we analysed the efficiency of soil erosion regulation practices over time, considering the total payment and the trends found in the baseflow. Whereas precipitation records present a decreasing trend (1 mm month−1), baseflow tends to increase by 0.018 m3 s−1 in the same period. Our findings show that soil conservation practices performed in the basin increase baseflow and also provide a better resilience to endure extreme events such as drought based on an increase in forest areas and soil conservation practices such as level terrace. Graphical abstract Unlabelled Image Highlights • We assessed the effects of Payment for Ecosystem Services on water provisioning and sediment transport using observed data. • Baseflow tends to increase by 0.018 m3 s−1 in five years; • Soil conservation practices reduced soil erosion by a quarter. [ABSTRACT FROM AUTHOR]

Highlights • We quantified the soil erosion change in a spatially explicit manner. • We investigated the driving forces of soil erosion change. • The hydrological effects of soil and water conservation were assessed. • The limitations and sustainability of soil and water conservation were discussed. Abstract Land degradation is a global environmental problem that threatens human safety and socioeconomic development. In order to alleviate severe soil erosion, China has implemented historically unprecedented large-scale afforestation. In this study, we selected the most severely eroded Loess Plateau as a case, to assess the effectiveness of soil and water conservation (SWC) efforts based on the Revised Universal Soil Loss Equation. In addition, the underlying drivers for soil erosion changes and hydrological effects of SWC were investigated, and finally the potential policy implications of our findings were discussed. The soil erosion intensity from 2000 to 2015 was weakened largely due to favorable climate conditions and SWC efforts, which promoted vegetation restoration and enhanced soil retention. However, there was a significant trade-off between water provision and soil retention functions. The excessively artificial afforestation reduced sediment yield but depleted surface runoff. Furthermore, artificial afforestation and increasing irrigation water consumption overused groundwater resources and finally lowered groundwater table. The SWC efforts characterized by artificial afforestation induced soil moisture declining, particularly for the conversion type of farmland to forest/shrub. Our results suggested that afforestation might be a poor choice in arid and semiarid regions, because it did not consider local precipitation conditions, and have exacerbated water shortages and offset SWC efforts. Therefore, the future ecological restoration efforts should be transformed from simple species-based measures to optimal plant species combinations to minimize the tradeoff between water yield and soil retention. The strategies for ecological restoration of drylands should also account for water balance to ensure effectiveness and sustainability. [ABSTRACT FROM AUTHOR]

Highlights • Decreases to labour availability lead to the use of fewer physical SWC techniques. • Remittances from migrants affect farm-level crop planting decisions. • Crop rotational composition determines the use of industrialized farming techniques. • The effects of out-migration in this community may be leading to land degradation. • Responses to out-migrations are likely to be specific to socio-ecological contexts. Abstract Rural-urban migrations are one of the most conspicuous patterns in global population shifts in recent decades and can have considerable impacts on land-use and management in the rural migrant-sending communities. To better understand these impacts, we employed household surveys and semi-structured interviews to generate a small, but detailed and relatively complete set of data (43 out of a total of 57 households) from a rural indigenous Kichwa community in the Andean highlands of Ecuador. We conducted linear regression analyses (LR) between migration-related attributes of each household and farm management variables in order to provide greater insight into the complex relationships and impacts of rural out-migration on farm and land management. Our findings indicated that reduced household labour availability was associated with a decrease in the use of physical soil and water conservation (SWC) techniques (p = <0.01), while remittances received from rural out-migrations were associated with an increase in the use of pesticides and chemical fertilizers (p = <0.01). The results of the LRs were used to develop a Structural Equation Model (SEM) to elucidate the direct and indirect effects between increased access to financial resources (as a result of temporary out-migrations) and the use of agro-chemicals and mechanized tillage (industrialized farming techniques). Our analysis suggests that temporary out-migrations were indirectly related to the use of industrialized farming techniques through their effects on household financial resources and subsequent farm-level decisions to increase the proportion of potato cash crops. As a consequence, it is probable that the effects of out-migration, at least in this case-study, are negatively affecting the agroecosystems of the landscape. However, the results of the SEM suggest that this response may be specific to this particular socio-ecological context. Rural development policies, programmes and projects must therefore explicitly recognise and better understand these broader socio-ecological contexts and their effects on farm-level decisions in view of rural out-migration in order to develop more effective intervention strategies. [ABSTRACT FROM AUTHOR]

Developing countries with an increasing population like Ethiopia experience degradation of land and water resources. To tackle this problem soil and water conservation (SWC) has been practiced and recently promoted by the Ethiopian government. However, the effectiveness of SWC practices on runoff and soil erosion have not been studied in detail for their long- and short-term effects. An integrated measurement and modeling study was conducted from 2012 to 2014 in the Gumara-Maksegnit sub watershed to assess the impacts of SWC structures on runoff and sediment yield using the Geospatial Interface for the Water Erosion Prediction Project (GeoWEPP) model. The study was conducted in two adjacent, smaller watersheds where SWC structures were constructed in one of the watersheds (treated sub watershed), while the other one was a control watershed without SWC structures (untreated sub watershed). The treated sub watershed has an area of 27.1 ha and the untreated sub watershed has an area of 31.7 ha. Runoff and sediment yield were compared based on the observations and GeoWEPP model simulations. The GeoWEPP model simulation results predicted the daily runoff satisfactorily for both sub watersheds (R 2  = 0.68 and NSE = 0.43 for untreated and R 2  = 0.61 and NSE = 0.84 for treated sub watershed). Similarly, the model prediction showed satisfactory results in sediment yield (R 2  = 0.61 and NSE = 0.59 for untreated and R 2  = 0.57 and NSE = 0.81 for treated sub watershed). SWC structures reduced slope gradient and changed flow accumulation. The observation and simulation study concluded that the treated sub watershed surface runoff was reduced by about 19% as compared to the untreated sub watershed. Similarly, the model estimated that SWC structures constructed in the treated sub watershed reduced the total area that generates soil loss above the set target limit of 10 t ha −1  y −1 from 49% to 38% of the watershed area. SWC has led to a significant reduction in sediment yield by 28 to 38% in these highland watersheds of Ethiopia. The results confirmed that SWC structures have a significant impact to prevent land degradation in the Ethiopian highlands. [ABSTRACT FROM AUTHOR]

Gully erosion is an important process of land degradation in mountainous regions, and is known to be one of the major sediment sources in eroded catchments. Recent studies have suggested that living and dead vegetation can be effective for ecosystem restoration, and large-scale restoration projects have been implemented in the tropical Andes in recent decades. However, few quantitative studies exist on the effectiveness of gully restoration to reduce sediment production and mobilization. In this study, sediment mobilization and transport was studied in five micro-catchments (<1 km 2 ) with different soil and water conservation treatments. The techniques that were used for soil and water conservation involve vegetation restoration on the hillslopes and check dams in active gully channels. To characterize the routing of sediment within the micro-catchments, we measured erosion and sediment deposition within the gully channels. Sediment yield was estimated from measurements of sediment accumulation in sediment traps that were constructed at the outlet of the micro-catchments. Flow barriers are shown to be very effective in stabilizing active gully systems in badlands through significant reduction (of >70%) of the amount of sediment exported from the micro-catchments. The construction of wooden barriers (or so-called check dams) in active gully channels enhances sediment deposition in the gully bed. The latter is strongly dependent on the rainfall intensity, as well as gully channel slope and vegetation cover. The experimental data suggest that there exists a threshold value of rainfall intensity (I 30 max) of about 23 mm h −1 , above which all sections of the gully system are actively contributing water and sediment to the river network. Also, forestation of active gully systems with rapidly growing exotic species such as Eucalyptus has a positive effect on the stabilization and restoration of the badlands, and effectively reduces the sediment export. [ABSTRACT FROM AUTHOR]

Erosion is severe in major agricultural sectors and areas of concentrated intense rainfall, such as southern Brazil, Argentina, India, eastern China, the Midwestern United States, Ethiopia, and Mediterranean Europe. To meet the world's food needs while protecting the environment, a more environmentally friendly agricultural model is needed. How much the adoption of introduced SWCP can contribute to food security is so, a puzzle that needs to be investigated today. Therefore, this research was conducted to evaluate the impact of soil and water conservation practices (SWCP) on food consumption score (FCS), and food intake in kilocalories at the household level by using 89 adopters and 161 non-adopter households. Cross-sectional data were produced from 250 samples by utilizing, a multistage sampling techniques. The causal effect of generated SWCP adoption data, were analyzed by propensity score matching model (PSM). Results gained by PSM show adoptions of introduced SWCP have an additional kilocalorie of 854.78. Concerning FCS, adopter households can obtain 7.28 scores of food frequency than their comparable groups. Since our study was limited to using analysis at the individual level and other food security indicators rather than calorie intake and FCS. Further study should be recommended concerning the impact of SWC on food security at the individual level by using multiple food security measure indicators. • The impact of introduced soil and water conservation measures on food consumption and caloric intake is overlooked in developing countries. • However, it improves soil fertility, which in turn increases crop production, contributing to household food consumption. • Participation in soil and water conservation activities is influenced by various socioeconomic characteristics. • The current study shows that participation in the program is likely to increase food intake frequency by 7.28 points and food intake by 854.78 Kcl for the participant groups. • Therefore, it is advisable to invest more in soil and water conservation to ensure food security in developing countries. [ABSTRACT FROM AUTHOR]

• A Soil-Water Conservation parameterization scheme was developed based on the GBEHM. • It revealed the spatiotemporal hydrological changes in the YRB during 1982–2019. • Impacts of the climate change and SWC measure on the runoff change were quantified. Intensive Soil and Water Conservation (SWC) has been conducted in the Yellow River basin (YRB) since the 1950s, which has greatly altered the eco-hydrological processes and particularly led to the runoff reduction. However, previous hydrological models performed in the YRB rarely simulated the SWC explicitly to quantify its spatiotemporal impacts. This study developed a SWC parameterization scheme based on the distributed physically-based model named Geomorphology-Based Ecohydrological Model (GBEHM). The hillslope SWC (HSWC) was parameterized as an additional surface storage capacity and simulated together with hillslope hydrological processes. The check dams along the river networks (i.e., river-networks SWC, RSWC) were parameterized as reservoirs and simulated together with the flow routing. The enhanced model (GBEHM-SWC) was first calibrated and validated using natural streamflow and remote sensing-based evapotranspiration. Then it was applied to analyze the hydrological changes from 1982 to 2019 in the YRB. Our simulation showed that, compared with the first period (1982–2000), the climatic factors (especially an increase of annual precipitation by 27.3 mm) would cause an increase of annual natural runoff by 2.9 mm (2.17 billion m3) in the second period (2001–2019). But in fact, the observed annual natural runoff decreased by 4.3 mm in the second period, which was caused by the reduction effects of the HSWC and RSWC by 3.8 and 3.7 mm (2.84 and 2.74 billion m3), respectively. Regarding the spatial distribution, the simulated natural runoff increased above Lanzhou and decreased on the Loess Plateau. The SWC impacts showed high spatial heterogeneity over the YRB, which offered useful information to evaluate the SWC measures. [ABSTRACT FROM AUTHOR]

Prolonged soil drying and severe moisture stress during the dry season, and soil saturation and erosion during the short rainy season are critical problems in the Ethiopian highlands. Large-scale implementation of bund structures has been used as soil and water conservation (SWC) measures to fight these problems and establish a sustainable land management (SLM) system. However, many SWC measures are implemented with design flaws or without proper design and maintenance, and do not match conservation requirements. The quality of implementation and effects of these bund structures on soil physical properties is not yet documented. Therefore, in this study, field investigations and laboratory analysis were carried out to evaluate the variation in bund structure design and its impact on soil-water retention, bulk density, porosity and soil depth. Results show that the dimensions and stability of bund structures, and consequently, the impacts of bunds varied widely. The widths and heights of bunds, and slope gradients were significantly correlated with infiltration rate and soil water content. Soil water content was 24% higher compared to that on untreated farms. Bunds with larger dimensions of top width (> 85 cm) and height (> 75 cm) showed 17 and 18% higher soil water content compared to fields with bunds having lower dimensions. In addition, results exhibited that the porosity and soil depth were significantly affected by the dimensions of bund structures and increased with increasing widths and heights of bunds. A 14% increase in porosity; a 41% increase in infiltration rate; and a 18% decrease in bulk density was found in soils of treated farms compared to those of untreated farm plots. Differences in particle size distribution and soil erodibility among widths of the bunds were low. It can be concluded that bund structure design varied substantially throughout the study area, which impacted soil water storage and soil physical properties. Bund structure design should be adapted to local biophysical settings at catchment level to enhance on- and offsite impacts. [ABSTRACT FROM AUTHOR]

Land degradation is a serious global problem because it leads to losses in food production and thus jeopardizes food security worldwide, particularly in developing countries. Despite numerous efforts to introduce sustainable land management (SLM) strategies and practices, their adoption by the primary target group, small-scale farmers in developing countries, has been [s]low. This study assesses the problem for the case of Ethiopia. The aim was to analyze the underlying factors that affect the adoption of SLM technologies in the Upper Blue Nile Basin. A detailed survey of 300 households and 1010 farm plots was conducted. Data were analyzed by using both descriptive and econometric analyses. Results show that farmers’ adoption of interrelated SLM measures depended on a number of socio-economic and farm-related factors in combination with the characteristics of the technologies themselves. For example, plot size and the availability of labor, as well as the gender of the household head, affected which SLM technologies were adopted by certain types of households. The adoption of SLM measures depended on the adaptive economic capacity of the farmers, which can be quite diverse even within a small region and can differ from the adoption potential in other regions. Our results suggest that SLM policies and programs have to be individually designed for specific target groups within specific regions, which in turn means that “one size fits all” and “across the board” strategies – which are quite common in the field of SLM – should be abandoned by development agencies and policymakers. [ABSTRACT FROM AUTHOR]

Surface hydrology can significantly influence biological soil crusts through altering runoff behavior. Hence, micro-organisms enrichment of degraded soil crust may be a novel and practical strategy to improve soil quality and surface runoff behavior. This study evaluated the impact of inoculating (i) bacteria, (ii) cyanobacteria and (iii) bacteria + cyanobacteria on soils, with the hypothesis this would improve runoff properties. Accordingly, we assessed the influence of microbial enrichment after inoculating the native cyanobacteria ( Nostoc , Oscillatoria and Lyngbya ) and bacteria ( Azotobacter and Bacillus ) on runoff onto a degraded soil under laboratory conditions. The cyanobacteria and bacteria were isolated from the studied soil, purified and proliferated in the laboratory, and then inoculated in individual or combined treatments onto soils placed into small experimental boxes. After 15, 30 or 60 days, the treatments were subjected to a simulated rainfall. We observed a significant ( p < 0.01) decrease in both coefficient and peak of runoff in the bacteria, cyanobacteria, and bacteria + cyanobacteria inoculated boxes relative to the control boxes. There was also a significant ( p < 0.01) delay in runoff start time (38–205%) and time to peak runoff (48–52%), and decrease in coefficient (74–96%) and peak of runoff (48–86%) in the bacteria, cyanobacteria, and bacteria + cyanobacterial-treated boxes compared to the control boxes. The most effective treatment was the inoculation of cyanobacteria after 60 days ( p < 0.01). In this treatment, the runoff coefficient was reduced 96%, the peak reduced 83%, the start time delayed 168% and time to peak reduced by 34% compared to the control. While these results need verification in the field, they suggest that inoculation of native micro-organisms particularly cyanobacteria, can be practically used to restore local hydrological cycles in the soil. [ABSTRACT FROM AUTHOR]

Research to measure soil erosion rates in the United States from natural rainfall runoff plots began in the early 1900′s. In Brazil, the first experimental study at the plot-scale was conducted in the 1940′s; however, the monitoring process and the creation of new experimental field plots have not continued through the years in either country, and are relatively rare in other parts of the world. To better understand runoff and soil erosion rates in Brazil, we review the plot-scale studies that have been conducted across the country. We also evaluated trends, challenges, and perspectives of plot-scale studies in Brazil. Runoff and soil loss records under natural rainfall were compiled from peer-reviewed journals, books, M.Sc. theses, and Ph.D. dissertations, and we organized a database containing the following information: geographic coordinates, region, rainfall, runoff, soil erosion, length of record (plot-years), land cover, tillage system, slope length, and slope gradient. We found mean values of observed annual soil loss ranging from 0.1 t ha y − 1 (grassland and pasture in the southern region) to as great as 136.0 t ha y − 1 (tilled fallow plots, without plant cover, in the northeastern region). Our findings indicated that the southern and southeastern regions of Brazil have the greatest number of runoff and soil loss monitoring sites and length of records (plot-years), corresponding to 67% and 88% of the totals, respectively. In addition, the number of plot-years of data collected has decreased 86% in the last 15 years. However, the number of published documents has increased 10 times in the same period. Around 50% of the experimental studies have 2 years or less of monitored data. In order to reduce the variability of the observed data, develop models, and support decisions, it is important to increase the monitoring period of the experimental sites. Moreover, efforts should continue to allow field observations in all regions of Brazil where data is scarce, in particular paying special attention to the central-western region, where crop production is the main land-use, and along the largest Brazilian agricultural expansion frontier (northern region). [ABSTRACT FROM AUTHOR]

Check dams are one of the most important engineering measures for controlling soil and water loss from watersheds and can play a key role in reducing sediment loads in rivers. In addition, the associated sediment deposits can in some circumstances provide a valuable source of information on changing rates of sediment production from the upstream watershed through time. A sediment profile with a depth of 11.325 m was examined within the deposits associated with a check dam at the outlet of the Nianyangou catchment, in the northern Loess Plateau, China, with a drainage area of 0.181 km 2 . The profile contained evidence of a total of 75 clearly identifiable flood event couplets, which corresponded to storm events occurring during the period 1960–1990. The variability of the grain size composition (clay content) of the sediment and its 137 Cs activity and organic matter (SOM) content down the profile was used to identify individual flood event couplets and the record of event rainfall (particularly extreme storm events) was used to establish a chronology for the individual flood event couplets. Based on the reservoir capacity curve and information on couplet thickness and sediment bulk density, the sediment yield associated with each flood couplet has been calculated. Using these data, annual sediment yields were estimated to range between zero in 1965 to 9750 t in 1984. The period from 1960 to 1990 was divided into three distinct phases based on evidence for changing rates of sediment production within the watershed above the check dam provided by a double mass plot of cumulative sediment yield versus cumulative precipitation. These phases represent the periods: 1960 to 1964, 1965 to 1983 and 1984 to 1990, which were characterized by mean annual specific sediment yields of 26,220 t km − 2 year − 1 , 5590 t km − 2 year − 1 and 19,130 t km − 2 year − 1 , respectively. This study is seen as demonstrating the potential for using the sediment deposits associated with check dams to obtain retrospective assessments of changes in sediment yield in repose to land use change and the implementation of soil conservation and sediment control measures. [ABSTRACT FROM AUTHOR]

The abundant surface runoff along with top fertile soil in rainy season, followed by sub-optimal soil water content (SWC) in root zone of the plants during post-rainy period is one of the major causes of low productivity and decline of citrus orchards in tropics. Keeping this in view, a study was conducted for seven years to evaluate the effects of different rainwater conservation techniques (RCTs) on runoff, soil and nutrients losses and yield of citrus orchard in Vertisols under a sub-humid tropical climate of central India. The RCTs: staggered trench (ST) and continuous trench (CT) with and without grass mulch (GM) were imposed in runoff plots (350 m 2 area) with 14 citrus plants across the slope (12%) and their performances were compared with without conservation measure (WCM) treatment. All the RCTs were effective in conserving rainwater, soil and nutrients (N, P, K, Fe, Mn, Cu and Zn), which imparted a favourable response on vegetative growth, leaf nutrient content, fruit yield and fruit quality of citrus plants. However, CT + GM produced the best response, conserving 49% runoff and 51% soil compared with WCM in the orchard. The available nutrients and organic carbon content in soil were significantly improved in mulched plots. The runoff generated made linear relations (R 2 = 0.82–0.91) with rainfall amount in treated plots, whereas this relationship was exponential (R 2 = 0.89) in WCM plot. However, the quantity of runoff made the linear relations with soil loss in both treated plots (R 2 = 0.76–0.89) and WCM (R 2 = 0.93). The rates of transpiration, photosynthesis and stomatal conductance of leaf and leaf water use efficiency of the citrus plants were higher under higher available SWC in CT + GM. The CT + GM produced 65% higher fruit yield with better quality fruits (higher juice content, TSS and ascorbic acid content with lower acidity) using 32% less irrigation water, resulting in 65% improvement in rainwater productivity and 143% improvement in irrigation water productivity compared with WCM. Citrus production with CT + GM was also found economically superior to other treatments, generating more annual net income (INR 125480 ha −1 ) with higher benefit-cost ratio (3.1). Overall results of this study demonstrates that the conjunctive use of CT and GM could conserve substantial rainfall runoff, soil and nutrients, resulting higher yield and water productivity using less irrigation water in citrus orchard in clay soil. [ABSTRACT FROM AUTHOR]

The loess plateau of northern China has always been severely affected by drought and rainfall, impacting ecological integrity and sustainable development in particular. Super-absorbent polymers (SAPs) can relieve the pressure of water shortages and change the process of rainfall-runoff. In this study, SAPs were mixed with soil in percentages(weight ratio) of 0, 0.25%, 0.5%, 0.75%, 1% and 2%; then, these mixtures were applied in 5 cm depth layers in runoff plots of 5 m × 4 m for every treatment (T1, T2, T3, T4, T5). Artificial rainfall intensity was controlled at 40 mm/h, and the rainfall duration was 0.5 h when the soil physical and chemical properties were surveyed. With SAPs, the initial runoff time of different treatments increased by 21.5-102.7%; the amount of surface runoff decreased remarkably; the SAPs could reduce the loss of soil and water: the runoff reduction effect was 24.6% (T1), 41.5% (T2), 46.5% (T3), 50.7% (T4), and 60.6% (T5); the sediment reduction effect was very significant at 58.8% (T1), 74.1% (T2), 85.6% (T3), 80.9% (T4), and 75% (T5); and the lowest losses of total nitrogen (TN 0.09 kg), total phosphorus (TP 5.02 g) and total potassium (TK 0.08 kg) were measured in T3,with 14.9%, 14.2% and 13.1% that of the control (CK), respectively. The soil moisture content increased by 19.2%, 32.5%, 33.5% and 31.3% compared to CK in the different soil layers; SAPs could raise the soil temperature by 0.72 °C (T5) and lower the soil temperature by 0.53 °C (T5) in September and July, respectively. The aboveground biomass and underground biomass of the treatments increased by a maximum value of 84.4% in T3, which was 38% greater than CK, and the vegetation in T3 (44 kinds) was the most abundant and it was 69.2% more than CK (26 kinds). The effect was not always positively correlated with the percentage of SAPs. The application of SAPs in this study showed a comprehensive utility (soil erosion prevention, redistribution of soil water and temperature, maintenance of fertility and the synergy between SAPs and plants), which suggest that the most basic goal, to ensure socio-economic and ecological sustainability in dryland systems, is obtained. [ABSTRACT FROM AUTHOR]

The middle reaches of the Yellow River Basin transport the vast majority of sediment (> 85% of the basin's total available sediment load), which has had profound effects on the characteristics of the middle and lower reaches of the Yellow River. Since the late 1950s, soil and water conservation measures have been extensively implemented in the Loess Plateau, China, especially since the 1970s. This has resulted in sediment discharge changing significantly. In this study, data from 22 catchments in the region of the Loess Plateau from Hekou to Longmen in the middle reaches of the Yellow River were analyzed to investigate the responses of the sediment regime to climate change and human activities. The non-parametric Mann–Kendall test and the Pettitt test were used to identify trends and shifts in sediment discharge. All 22 catchments had a significantly decreasing trend ( P < 0.01) in annual sediment discharge. Change point years were detected between 1971 and 1994, and were concentrated between 1978 and 1984 in 17 catchments. Moreover, erosive rainfall exhibited a tendency to decrease, but this was not a significant trend. Compared to rainfall, human activities, primarily soil and water conservation and environmental rehabilitation campaigns, have played a more prominent role in the changes in sediment regimes. In order to reduce soil erosion and sediment yield, more attention should be paid to proper and rational soil and water conservation and eco-restoration in this region. [ABSTRACT FROM AUTHOR]

In the drought-prone Upper Blue Nile River (UBNR) basin of Ethiopia, soil erosion by water results in significant consequences that also affect downstream countries. However, there have been limited comprehensive studies of this and other basins with diverse agroecologies. We analyzed the variability of gross soil loss and sediment yield rates under present and expected future conditions using a newly devised methodological framework. The results showed that the basin generates an average soil loss rate of 27.5 t ha − 1 yr − 1 and a gross soil loss of ca. 473 Mt yr − 1 , of which, at least 10% comes from gully erosion and 26.7% leaves Ethiopia. In a factor analysis, variation in agroecology (average factor score = 1.32) and slope (1.28) were the two factors most responsible for this high spatial variability. About 39% of the basin area is experiencing severe to very severe (> 30 t ha − 1 yr − 1 ) soil erosion risk, which is strongly linked to population density. Severe or very severe soil erosion affects the largest proportion of land in three subbasins of the UBNR basin: Blue Nile 4 (53.9%), Blue Nile 3 (45.1%), and Jema Shet (42.5%). If appropriate soil and water conservation practices targeted ca. 77.3% of the area with moderate to severe erosion (> 15 t ha − 1 yr − 1 ), the total soil loss from the basin could be reduced by ca. 52%. Our methodological framework identified the potential risk for soil erosion in large-scale zones, and with a more sophisticated model and input data of higher spatial and temporal resolution, results could be specified locally within these risk zones. Accurate assessment of soil erosion in the UBNR basin would support sustainable use of the basin's land resources and possibly open up prospects for cooperation in the Eastern Nile region. [ABSTRACT FROM AUTHOR]

In the north-western highlands of Ethiopia investments in land management (LM) have not always been successful. The objectives of this study were to assess farmers’ perceptions about implementation approaches of soil and water conservation (SWC) practices and to explore the relationship between the different dimensions (factors) of social capital and investments in LM practices. Simple descriptive statistics were applied to analyse the implementation approaches, while factor analysis was used to reduce the social capital variables to six non-correlated factors for subsequent analysis. The Ordinary Least Square (OLS) model was used to analyse the effects of social capital dimensions on investment in three LM practices: bunds, compost and fertilizer. The study showed that the majority of the farmers state that they prefer the mass mobilization approach (which embodies social capital) to implement SWC practices. But farmers also pointed out several shortcomings of the mass mobilization approach (e.g., inefficient in labour utilization, lack of benefit sharing mechanism). The OLS model shows that the different dimensions of social capital affect investments in the LM practices differently. In particular, cooperation and trustworthiness positively influence investments in bunds and fertilizer use, while the extent of participation in formal institutions has a positive effect on fertilizer use and compost. Understanding and making use of these relationships could help in designing and implementing LM policies, strategies and programmes. [ABSTRACT FROM AUTHOR]

Soil and water conservation (SWC) can influence the amount of sediment yield leaving a catchment and the availability of water for up- and downstream stakeholders. The extent of this influence depends heavily on hydro-climatic conditions in the upstream catchments. This study investigated the changes in blue and green water distribution and sediment yield in a meso-scale catchment in the Wet Wenya Dega agro-climatic zone in the upper Blue Nile basin, where the implementation of SWC measures has been documented for the last 29 years. We implemented the temporal and spatial variability of SWC in the form of terracing into the Soil and Water Assessment Tool (SWAT) and modelled its influence on discharge and sediment load. Using the Sequential Uncertainty Fitting program (SUFI-2), we calibrated and validated discharge and sediment load with a 31-year data set from a sub-catchment (113 ha) and validated the model for the entire catchment (4818 ha) with a two-year data set. Modelling showed that discharge at the catchment level, and thus water availability for downstream stakeholders, did not change significantly with the implementation of new SWC measures, but SWC could substantially reduce sediment yield. Two modelled SWC scenarios showed that with the implementation of SWC measures the average annual sediment yield of the study area could be reduced from 37 t/ha to 17 t/ha. [ABSTRACT FROM AUTHOR]

Objective The present study aimed to evaluate the quantitative effect of polyacrylamide (PAM) on runoff and soil loss, and the amount of PAM polymer and acrylamide (AMD) monomer emissions from experimental plots under laboratory conditions. Materials and methods The different levels of treatment of 0, 0.4, 0.6, 1, 2, 3, 4, and 6 g m − 2 PAM were applied to small plots of 0.05 m 2 installed in the Rainfall and Soil Erosion Simulation Laboratory of Tarbiat Modares University, Iran, with a simulated rainfall intensity of 72 mm h − 1 , duration of 0.5 h, and slope of 20% (i.e., 11.5°) applied to a silty loam, similar to that for real conditions. To determine the optimal level of PAM application for soil and water conservation under laboratory condition, PAM polymer and AMD monomer were measured in outing runoff and sediment. An analytical technique based on a spectrophotometer was developed to quantify the amount of PAM polymer present; the determination of amide groups by the NBM was also formulated for the quantification of PAM polymer. The background AMD concentrations in runoff and sediment were determined using the EPA method 8032A in triplicate. The analysis of AMD was performed on a gas chromatograph system equipped with an electron capture detector and Clarity 4.2 Data Acquisition software. Results The results proved a significant PAM polymer emission in runoff and sediment (P < 0.001), a significant AMD monomer emission in output runoff (P < 0.02), and no significant AMD residue in the output sediment (P > 0.32). The optimal amounts of PAM application that are based on PAM and AMD residues in runoff and sediment and minimum soil loss were at rates of 2 and 0.4, and 2 and 1 g m − 2 , respectively. Conclusions The results of this research could be helpful in providing appropriate information to address environmental concerns regarding PAM application for soil erosion control as well as in conservational and engineering planning. [ABSTRACT FROM AUTHOR]

• A mixed effects meta-analysis of coal mining on soil and water conservation at watershed scale. • Time series of runoff was significantly decreased since the coal mining. • Coal mining increases soil infiltration. • Coal mining resulted erosion may be buffered if appropriate revegetation measures were applied. Coal mining is a critical energy industry that considerably evolves and benefits the modernization and development of our society. However, the side-effects such as degraded air and water quality, fragmented vegetation landscape, and aggravated soil erosion associated with coal mining also raise serious concerns. Previous studies have shown diverse hydrologic cycle responses after coal mining when the watershed is subjected to different magnitudes of local climates, soil properties, mining methods, and watershed area. How these factors combine to affect hydrologic cycle responses to changes in mining remains unclear. A meta-analysis including 717 paired observations collated from 62 studies worldwide was used to evaluate the effects of coal mining on soil and water loss at a watershed scale. The results showed that runoff, runoff depth, and spring flow due to coal mining were significantly decreased by 24.46 %, 32.55 %, and 56.88 %, while calculated soil erosion modulus and soil loss based on empirical equations were significantly increased by 202.44 %, and 199.50 %, respectively. As runoff is the carrying force for soil loss, the decreased runoff would actually reduce the carrying capacity of soil to enter the river system. Therefore, the increased soil loss intensity and decreased runoff may lead to insignificant total soil loss (−68.52 t hm−2). In addition, coal mining decreases groundwater level (−11.02 %) and baseflow (−14.46 %), increases infiltration rate (42.86 %), soil erodibility K value (258.67 %), sediment yield (141.86 %) and soil erosion area (102.06 %). Among them, mean annual precipitation plays a dominant role in driving hydrological cycle processes, while combined use of above-ground and underground mining tends to increase soil erosion. This study is crucial to a better understanding of soil and water conservation under coal mining activities. [ABSTRACT FROM AUTHOR]

• Poor palatability allows eco-grass to accumulate litter in grassland community. • Eco-grass reduces soil loss by increasing rainfall interception and water infiltration. • Eco-grass has ecological benefits and soil and water conservation benefits. Ecological grasses (eco-grass) have poor palatability and are less popular than forage grasses, receiving little attention for many years, despite their increased survival regarding livestock on the Qinghai-Tibetan Plateau. Eco-grass restoration has the functions of increasing vegetation coverage, preventing soil and water loss, conserving water sources, and preventing pika and insect pests. However, the effects of the eco-grass on soil and water conservation are still unclear. Here, a field experiment was conducted to determine the effects of an eco-grass species (Elymus tangutorum) on the processes of soil and water loss in alpine hillslopes grasslands on the eastern Qinghai-Tibetan Plateau. The results showed that the soil loss rate decreased with the increase of litter biomass in the presence of the selected eco-grass. The presence of eco-grass reduced the soil loss rate by 65% and this was mainly associated with the increase of the rainfall infiltration rate and litter interception rate. Our findings showed that eco-grass could take into account both soil and water conservation and ecological benefits in alpine hillslope grasslands. Therefore, eco-grass should be considered and extensive application to maintain the multifunctions and stability of artificial hillslopes grassland on the Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR]

[Display omitted] • Over the last three decades, 123 articles regarding the assessment of rainfall erosivity in Brazil were published. • EI 30 has been the most employed erosivity index in the country. • Pluviographic rainfall data and regression equations are the main methods for obtaining erosivity values. • Kriging is the most widespread technique for obtaining rainfall erosivity maps. • The complete database with all information retrieved from literature was made available. In this paper, we report the results of an in-depth review of scientific literature on the assessment of rainfall erosivity in Brazil and published in peer-reviewed journals over the last three decades. In total, 123 articles regarding this topic in Brazil were published. These studies were analyzed and filtered into categories regarding the bibliographic information, methodology scope, and main results. It was found that the EI 30 has been the most employed erosivity index in the country, while the use of pluviographic rainfall data and regression equations are the main methods for obtaining erosivity values. The magnitudes of annual rainfall erosivity reported for the Brazilian territory range from 59 to 26,891 MJ mm ha-1h−1 year−1. The lowest values are found in the Northeast region and the highest in the North. Kriging is the most widespread technique for obtaining rainfall erosivity maps in Brazil. Furthermore, the Southeast region accounts for the largest number of erosivity studies, while the North has a major lack of erosivity information. The advancements over the last decade are characterized by the use of synthetic series of rainfall and remote sensing products to estimate erosivity, as well as the use of machine learning techniques for its interpolation. For the next years, an increase in the use of these methodologies is expected, as well as an intensification of the assessment of the future patterns of rainfall erosivity over the country. The present review updates the findings regarding the assessment of rainfall erosivity in Brazil and brings a wider overview of the erosivity studies in the country. The information here summarized contributes to the establishment of a conservationist planning of soil and water management on a national scale. Finally, the complete database with all information retrieved from the literature was made available. [ABSTRACT FROM AUTHOR]