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Technologies used in the pulp and paper industry at the turn of the 20th and 21st centuries have undergone significant changes. Increasing pressure to reduce emissions of pollutants contributed to the application of new, better technological processes. In addition, the savings of non-renewable resources, as well as the reduction of the amount of solid waste generated, are the main assumptions of modern production technologies in this industry. The aim of this study was to evaluate the impact of pulp and paper factory on the content of heavy metals and sulphur in nearby soils. The research material included 65 soil samples. 35 samples were collected from 6 soil profiles, the other 30 were surface and subsurface soil samples from 15 research points. Selected physicochemical properties of soils were determined: soil texture, soil pH, TOC, CaCO3 content and electric conductivity. The total content of heavy metals in the soils was determined by AAS after digestion in hydrofluoric acid and bioavailable forms in 1 M DTPA. The content of total and sulphate sulphur was determined by spectrophotometry according Bardsley and Lancaster method (1960). The research found low impact of pulp and paper factory on the content of heavy metals and sulphur in soils, however, due to a very large scale of this kind of industry, the moderately contaminated sulphur category and very high polluted mercury category of geo-accumulation index indicate the need of repeating the research within the next several years.

Self-citation is a common practice in soil science publications, but can we find a common behaviour in soil science papers, and are there outliers? Here we investigate self-referencing (referencing earlier papers on which a researcher is an author or co-author) for papers published in nine leading soil science journals (Soil Biology and Biochemistry, Geoderma, Soil & Tillage Research, Catena, European Journal of Soil Science, Soil Science Society of America Journal, Soil Use and Management, Geoderma Regional, and SOIL) in 2018 to understand the self-referencing distribution of soil science papers. From 1753 research and review papers, a typical soil science paper (based on median values) had 5 authors, 56 references, and 10 pages. Interestingly, these numbers were very similar across all nine journals. We found that the median rate of self-referencing was 10%, and an interquartile range from 5 to 17%. The values were also very similar across the nine journals. The self-referencing values were reasonable and comparable to other disciplines and a past study of pedometrics papers. Self-referencing rates increase with the number of references and authors. However, its distribution was quite variable but tended to be less than 25% for papers with less than 10 authors with less than 60 references. We further conducted a graphical procedure on the self-referencing distribution to establish outlier thresholds related to the inter-quartile range. We found thresholds of self-referencing between 35% and 53%, which would suggest high values. There were only 61 papers (3.5% of total) above the lower threshold. We also established median and 80-percentile models based on the number of authors and the number of references. Based on the data, we can present an acceptable range of self-references, followed by an expert interpretation of the citation behaviour. This way can help authors, editors and reviewers to understand whether exceptional citation is at work.

In this study, we used a new approach to measure and determine the splash detachment based on theories of soil erosion, the large number of articles published on the topic and simulated rainfall experiments. It is a necessity to use and improve new methods to accurately evaluate and quantify the processes of soil erosion. In this experiment, a soil pan with three areas, which consisted of a test area, complementary border area and a splash collector for slots, was used to obtain the ability of soil to undergo splash detachment. In this study, the soil surface was uniform and composed of a smooth slope and depth of thin layer flow that was

Root anchoring in the soil provides significant resistance for trees to resist against the wind and potential soil shear failure in a slope. Soil conditions and root properties affect pullout resistance of plant roots in the soil, which govern the anchoring capacity of plants. Soil water conditions may change considerably during rainfalls and affect the anchoring capacity of plant roots. Therefore, research on the effect of soil water conditions on plant roots' pullout behavior is essential to better understand the anchoring of plants in the soil during rainfall. In-situ pullout tests on roots of Paper Mulberry are carried out at various soil water conditions. Significant findings in this research are: (1) the initial pullout stiffness decreases with root length and soil water content; (2) increase in soil water contents causes a noticeable reduction in the soil-root bond strength; (3) the soil-root bond strength decreases with root length; (4) the pullout resistance for roots tested in the field takes into account root branching and interlocking of root hairs with surrounding undisturbed soils.

In this short paper some examples of tafoni and similar features of cavernous weathering are described from Western Scotland and Southern Greece, including Crete and the Santorini group. All these forms belong to the younger Holocene. This age is indicated by young tectonic emergence from the sea, historical data, or the well known volcanic history of Santorini. Pre-Holocene tafoni are neither more widespread nor better developed than those of the last 2000 or 3000 years. Very different rocks are weathered into tafoni features: old and young sandstones and calcareous sandstones, pliocene conglomerates, eolianites, or lavas and holocene tephra. The tafoni are nearly in all cases strongly oriented towards the present sea front, and therefore salt weathering should be the most effective process.

Laboratory studies were conducted to select a most appropriate among natural (coarse rice husk, fine rice husk, and saw dust) and among synthetic (polyvinyl alcohol, polyacrylamide, and polyvinyl acetate) organics to improve aggregate stability of the sodic sandy loam soils. Multiobjective programming applied to multi-structural index (water dispersible silt plus clay, saturated hydraulic conductivity, and modulus of rupture) identified fine rice husk and polyvinyl alcohol as the most suitable in the respective groups.

Phosphoric fertiliser has enormously contributed to agriculture; however, it generates five tonnes of phosphogypsum per ton of phosphoric acid synthesised. Phosphogypsum houses heavy metals and long-lived radioactive elements that represents an environmental issue requiring remediation. This paper presents a methodology for characterising phosphogypsum deposits using geophysical, geochemical, and statistical tools. Gamma-ray probes determined the abnormal radioactive zones within the phosphogypsum deposits while electrical resistivity tomography provided the geometry and distribution of the phosphogypsum deposits. Chemical results confirmed the high presence of heavy metals in the waste determining chromium as the most concentrated metal. Radiological measures indicate that the effective ambient dose equivalent average in the study area surface is approximately 8.5 times higher than the average for Europe. While at 1.0 m depth, in the phosphogypsum layer, the ambient dose equivalent average surpasses approximately 27 times the European average. Statistical correlation analysis supports that the radiation increases due to the uranium presence. This methodology might reduce time and cost avoiding the use of expensive traditional methods, and it is exportable to any deposit. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

[EN] In many Mediterranean areas, citrus orchards exhibit high soil loss rates because of the expansion of drip irrigation that allows cultivation on sloping terrain and the widespread use of glyphosate. To mitigate these non-sustainable soil losses, straw mulch could be applied as an efficient solution but this has been poorly studied. Therefore, the main goal of this paper was to assess the use of straw mulch as a tool to reduce soil losses in clementine plantations, which can be considered representative of a typical Mediterranean citrus orchard. A total of 40 rainfall simulation experiments were carried out on 20 pairs of neighbouring bare and mulched plots. Each experiment involved applying 38.8 mm of rain at a constant rate over 1 h to a circular plot of 0.28 m(2) circular plots. The results showed that a cover of 50% of straw (60 g m(-2)) was able to delay the time to ponding from 32 to 52 s and the time to runoff initiation from 57 to 129 s. Also, the mulching reduced the runoff coefficient from 65.6 to 50.5%. The effect on sediment transport was even more pronounced, as the straw mulch reduced the sediment concentration from 16.7 g l(-1) to 3.6 g l(-1) and the soil erosion rates from 439 g to 73 g. Our results indicated that mulching can be used as a useful management practice to control soil erosion rates due to the immediate effect on high soil detachment rate and runoff initiation reduction in conventional clementine orchards on sloping land, by slowing down runoff initiation and by reducing runoff generation and, especially, sediment losses. We indirectly concluded that straw mulch is also a sustainable solution in glyphosate-treated citrus plantations., This paper is part of the results of research projects GL2008-02879/BTE, LEDDRA 243857 and RECARE-FP7 (ENV.2013.6.2-4).

Soil legacy data is ubiquitous and usually contains routine soil analysis information. In Iran, like most places, legacy soil data constitutes genetic horizon soil information recorded from excavated soil profiles. Describing and sampling from each genetic horizon is assumed to be heterogeneous from site to site. Digital soil mapping (DSM) using observed data is valuable because it provides a means to exploit the available information together with leveraging commonly available information by way of environmental covariates. It creates a much more detailed view of soil at the landscape scale. The purpose of this paper is to model and map the spatial distribution of nitrogen, phosphorous and boron at four standardized depths: 0–15, 15–30, 30–60, 60–100 cm, in an area of 7300 ha in the north west of Iran, and compare different model types. To circumvent the issue of heterogeneous soil depth observations from site to site, mass-preserving soil depth function splines were used to harmonise the soil profile observed data to the aforementioned standard depths. This facilitated the spatial modelling of each of the target variables for each standard depth with the aim of creating digital soil maps. Twenty-three covariates were extracted from a publically available digital elevation model (DEM) as well as freely available Landsat 8 ETM+ imagery. The DEM-derivative covariates used in this study were divided into three main categories: i) Morphometry; ii) hydrology; and iii) lighting visibility. Both Random Forest and Cubist were assessed as candidate models for predicting each target variable. The results showed that Cubist was the most accurate method. Terrain attributes play an important role in estimating N, P, and B, while optical images do not have significant role. The most important findings of this paper in terms of environmental hazards are that the inundated regions in the west part of the study area are susceptible to boron contamination, providing future guidance for remediation.

Connectivity analysis has proved a very valuable approach in understanding runoff and sediment fluxes in catchments. Many analyses use Connectivity Indices to model the patterns, but various versions of the Index have been developed. This paper tests the effects of these variants of the Index as applied to an agricultural-terraced catchment in the semi-arid Mediterranean region where occurrence of connectivity is relatively well documented to validate the modelling. This paper compares three versions of the Connectivity Index that use vegetation/land use (C), topography (RI) and roughness (n) as the weighting factors. Two different slope algorithms are also tested. The weightings are derived from a UAV (drone) survey, with simultaneous ground field mapping. The UAV imagery is found to provide a good, high resolution basis for determining detailed topography and vegetation cover. The slope limit present in some modelling is found to be unsuitable in this landscape where steep terrace embankments that are vegetated in places, and also partially vegetated uplands, occur. Subsequent modelling removed the slope limit. The major patterns of flow produced are similar between the models and are largely related to the overall topography and major drainage lines but considerably modified by the terracing. The model outcomes differ in detail, with the C factor model, incorporating vegetation, coming nearer to the field situation. The main deficiency in all the indices is the weakness in modelling ponding and sedimentation created by the terraces, and therefore the disconnectivity in the landscape. Comparison with field data confirms the variable connectivity in rainstorms, the effects of features such as tracks, and the effect of management actions. Evidence from field mapping during the last two decades indicates that the models probably represent the maximum possible functional connectivity.

Plants roots are beneficial for slope stabilization as they can reinforce the soil shear strength. Though the effect of root distribution characteristics has been studied a lot, the spatial interaction mechanisms of soil-root blocks on pull-out tests around the tree stem are still poorly understood. This paper aims to analyze the effect of root spatial distribution and properties on the behavior of soil resistance around the tree stem by field pull-out tests on a slope covered by Vitex negundo L. var. heterophylla . The relationships between the pull-out strengths and root properties at different positions were compared; and the branch root mechanics were used to explore the correlation between root spatial distribution and soil resistance behavior. The results show that roots evenly distribute in a 0.7 m radius around the main stem. In the position on both sides of the pull-out direction, coarse roots are mainly located near the main stem, while fine roots are farther. Roots develop the highest soil resistance of 2207 N with respect to the pull out direction and 508 N against the pull-out direction. When a higher number of roots with diameter 5 mm behind the tree stem, the soil resistance are much greater. Branching points have little impact on pull-out strength. Besides, friction at the root-soil interface in either along or against the pull-out direction is greater than bilateral direction of the tree stem. In addition, the results of this paper can present the response of roots around the tree stem subjected to pull-out force, which can be considered in selecting and collocating of plant species in eco-engineering. The methods in this paper can be taken as a reference in analyzing the effect of root properties on soil resistance.

In this paper, we analyse the significance of alluvial substrates in shaping the morphodynamics of the bottom of a lowland river valley. The research focus was a 20-km reach of the Bug River valley, an example of a large river in the Polish Lowlands. There are no anthropogenic elements in the valley that can disturb the course of natural river processes. The Bug River channel has not been engineered in the section analysed. Eighty-one geological drillings performed in the channel allowed identification of 11 zones of sub-alluvial bedrock protrusions built up from erosion-resistant deposits. The determination of the valley bottom surface morphology was based on high-resolution multispectral satellite images in natural and near-infrared colours. Geological and geomorphological mapping of the valley bottom surface were also carried out. The obtained results showed that the key factors controlling the morphodynamics of this floodplain are protrusions of sub-alluvial bedrock. Under medium- and low-flow conditions, these are hidden under a layer of channel deposits. However, during high flows, the surface of the protrusions is exposed, affecting the pattern of flood flows and forcing them to enter the floodplain in certain, recurrent zones. The result of such phenomenon is the creation of characteristic sets of accumulative and erosive landforms. Thirteen types of such forms have been identified. The presence of sub-alluvial bedrock protrusions in this river channel has promoted formation and persistence of ice jams (confirmed by analysis of hydrograms from 1969 to 2018). The case presented in this paper shows that the certain arrangement of landforms indicate morphodynamic specificity of valley bottom whose alluvial substratum exerts an influence on flood flows. Since protrusions of alluvial substrate is associated with glacial genesis of the area cut by the Bug River, the described phenomenon may also occur in other postglacial areas.

Pumice, a component of pyroclastic soils, undergoes a grain crushing process, even at lower stress level, with the resulting decreasing in shear strength in such material. According to the content already discussed in Esposito et al. 2013, this paper is focused on the attempt to further correlate the in situ measures acquired on these kinds of soils, in particular about suction, humidity and saturation, to the mechanical behavior observed in laboratory. The data collected in situ during 19 months, to cover both dry and wet cycles, supported the evidence that the wetting and drying conditions of such soils, due to the analyzed meteoric precipitations, fulfilled the required conditions that may induce the phenomenon of grains crushing. Hence, we have further explored the connection of these kinds of phenomena introducing new elements of discussion such as the decay of the mechanical characteristics, in situ measurements of the hysteretic relation between the suction and the soil water content, investigation about the occurrence conditions of static liquefaction and more. The research was developed by selecting, as test case, a wide area around Naples and the Vesuvius (Italy), affected, in particular, by frequent landslide phenomena, due to the instability of the pyroclastic cover, such as the events occurred at Monte Faito, Nocera Inferiore, Coroglio and Monte di Procida Ridges. Evidence of a marked influence of the wetting-drying cycles on the pumice crushing and on the resulting structural collapse phenomena, was observed during laboratory tests. The issues and the related discussion addressed in this paper could be useful in order to identify the triggering phenomena of shallow collapses, fast landslides, flow liquefaction and more, where pyroclastic covers, similar to those coming from the selected areas, are located.

The stability evaluation of rainfall-induced landslides using a physical determination model supports disaster prevention, but it is mostly applied to the area with few landslides, and there is a lack of quantitative study on rainfall and landslide stability. This paper combined the Scoops3D model with the TRIGRS model (3D) to predict the shallow landslide spatiotemporal distribution and compared the simulation results with those of the TRIGRS model alone (1D), aiming to obtain more accurate assessment results. At the same time, the relationship between landslide stability and accumulative rainfall was quantitatively fitted to improve the real-time landslide prediction system. We applied the 1D and 3D models to the July 21, 2013 group-occurring landslide event (976 shallow landslides) in the Niangniangba basin, China. The required geotechnical parameters of both models were acquired by field and laboratory tests. We calculated the pressure head over time using the TRIGRS model based on practical rainfall data and predicted the shallow landslide stability using the Scoops3D model according to the resulting piezometric surface. We compared the landslide stability spatial distributions of the two models under initial and saturated conditions with the landslide catalogue. The success rate of landslides predicted by 3D model is 4.20% higher than 1D model. A composite index to quantitatively evaluate both models’ performances indicates over-prediction by the 1D model in the stable region, while the 3D model more effectively predicts shallow landslides with a smaller unstable region. The relationship between instability proportion and accumulative rainfall in the 1D and 3D model can be represented by y = 24.57 x 0.18 and y = 11.59 x 0.33 , respectively. The 3D model shows more conservative result, and the rainfall threshold analysis proposed in this paper can provide reference for the time of most landslides in the case of insufficient data, which is an important indicator for disaster early warning and prediction.

In recent years the concept of connectivity has emerged in sediment management to describe transfer of sediment from different sections of landscapes at various spatial and temporal scales. The sediment connectivity concept has two distinct components: structural and functional. Structural and functional sediment connectivities have a hard and soft nature, respectively, in which the former relates to physical characteristics and the latter to soil erosion and sediment transport processes. Although there has been an increase in sediment connectivity studies over the last decade, disagreement and confusion seems to remain about conceptual and especially methodological approaches, related indices, methods of quantifying sediment connectivity at a range of spatial and temporal scales, and the current situation in sediment connectivity research. A review of the relevant literature is needed to address these issues and provide a holistic overview of different aspects of sediment connectivity which would enlighten the directions of future research. In this review, 117 papers have been classified into five different categories, namely (i) developing conceptual frameworks; (ii) depicting spatial and temporal distribution of sediment source and sink areas; (iii) developing sediment connectivity indices; (iv) using and developing models; or (v) investigating sediment delivery likelihood through a network analysis approach. The reviewed contributions within each category were 8%, 23%, 55%, 10% and 4% papers respectively. The results indicated that more studies at both global and local scales are necessary to achieve a comprehensive conceptualization of sediment yield and related processes using sediment connectivity. Most studies have concentrated on static characteristics rather than dynamic aspects of connectivity, leading to mainly structural-based methods and indices, resulting in less attention being paid to functional connectivity. Process-based sediment connectivity studies, by focusing on spatio-temporal variations of sediment transport throughout a watershed, will therefore be a crucial aspect in future studies.

To understand the research trends and areas of focus on the Chinese Loess Plateau (CLP), a bibliometric study based on the Science Citation Index-Expanded (SCI-E) was performed. This study presented a comprehensive overview of the field based on the annual outputs, research areas, temporal trends in keywords, marked journals, institutions, and authors. In the SCI-E database, only 17 outputs occurred before 1991. Thus, we chose the study period between 1991 and 2018. The results revealed that the annual number of publications increased, with an especially rapid increase after 2006. Geology, environmental sciences and ecology, agriculture, water resources, and physical geography were the most popular Web of Science research areas. A keyword analysis indicated that “climate” was the most popular study area. After 2006, the research areas changed to “impact”, “dynamics”, and “land use change” topics in mechanisms and regulation. Since 2011, coupled effects among the environmental factors have been incorporated in research on the CLP. The areas of focus range from classical geology to agriculture research, ecological construction research, and research on the efficient use of resources. Catena and Palaeogeography Palaeoclimatology Palaeoecology were the most popular journals for researchers to publish their research results, and these two journals also had greater influence in the field with larger numbers of citations than other journals. The institution with the greatest research output and most citations was the Chinese Academy of Sciences. An Z. S., Fu B. J., Liu T. S., Ding Z. L., Shao M. A., and Lu H. Y. were the most competitive authors based on their large numbers of papers and citations. This paper presents an attempt to better understand the progress in research on the CLP.

Soil water erosion on cultivated lands represents a severe threat to soil resources in the world, and especially in Mediterranean areas, due to their topographic, edaphic and climatic conditions. Among the cultivated lands, vineyards deserve a particular attention because, aside representing one of the most important crops in terms of income and employment, they also have proven to be the form of agricultural use that causes one of the highest soil losses. Although the topic of soil water erosion on vineyards has been studied, it still raises uncertainties, due to the high variability of procedures for data acquisition, which consists into different scales of analysis and measurement methods. There is still a great gap in knowledge about the effect of triggering factors on soil water erosion and, so far, an effort to quantify this effect on the Mediterranean viticulture has not been made yet. Therefore, this paper review aims to (i) develop a documented database on splash, sheet and rill erosion rates in Mediterranean vineyards, (ii) identify and, if possible, quantify the effect of triggering factors such as topography, soil properties, rainfall characteristics and soil conservation techniques on soil water erosion, and (iii) provide suggestions for a more sustainable viticulture. Although the large variability of data, some general trends between erosion rates and triggering factors could be found, as long as data were categorized according to the same measurement method. However, no general rule upon which to consider one triggering factor always predominant over the others came out. This paper review supports the importance of monitoring soil water erosion by field measurements to better understand the relationship between the factors. However, protocols should be established for standardizing the procedure of collecting data and reporting results to enable data comparison among different study areas.

Floodplain deposits in the valley of the Moskva River contain a series of buried soils of the Holocene age, which can be an important source of paleoecological information. These soils were dated as follows: Soil 1 — 100 BP, Soil 2 — cal 1200 AD–500 BC, Soil 3 — 900–2700 BC, and Soil 4 — 3700–6000 BC. Archeological monuments associated with these soils belong to the Neolithic (Soil 4), Early Bronze Age (Soil 3), and Iron Age and Middle Ages (Soil 2). Buried soils have well developed profiles and diagnostic features. Dark-colored soils of the Atlantic period (Soil 4) in most cases can be attributed to Phaeozems. Pollen analysis shows that these soils were formed under forest-steppe communities. Buried soils of the Subatlantic period (Soil 2) are usually referred to as Luvisols. Unlike them, the soils of the Subboreal period (Soil 3) are traced in rare cases and have no clear diagnostic features allowing reconstruction of the paleoenvironment. These soils have a light-colored humus horizon, which does not allow them to be classified as Phaeozems. However, they do not have the Bt horizon characteristic of Luvisols. This paper describes the results of a new comprehensive study of the Moskva River floodplain near the Zvenigorod Biological Station (ZBS) of Moscow State University. The buried soils of the Atlantic and Subboreal periods were studied by palaeopedological and palynological methods. The findings confirmed previously obtained results and indicated that the buried Soil 3 at the ZBS site could be developed under mixed forests dominated by spruce. These results suggest that the landscapes of the lower levels of the valley changed dramatically between 5000 and 4500 cal BP. The forest-steppe communities were replaced by dense forests due to the early Subboreal climate change. The paper also examines the specifics of soil and pollen records of the landscape evolution. The anthropogenic influence on the floodplain landscapes is also considered.

In this paper we analyse the geomorphic response of a mountain river (Upper Cinca River, Central Southern Pyrenees) in relation to multi-scale disturbances during almost a century (i.e., 1927–2015). The integration of multiple geomorphic descriptors (i.e., morphology and topography) and disturbances (i.e., floods, land use changes, dams, embankments and gravel mining activities) allows better understanding of the cause-effect relations and their significance. The paper presents a novel methodology integrating the application of SfM-MVS algorithms to historical imagery to extract multitemporal channel topography and morphology; and the use of statistical tools to infer on the existence of significant trends and breakpoints in the temporal evolution of the geomorphic descriptors and disturbances. Results show that afforestation was the main land use change exhibited between 1957 and 2015, although mainly concentrated during 1977–2015. Annual runoff presented a general negative trend with a wet (1959–1983) and dry period (1983–2015). Extensive gravel mining occurred after flood events, together with channel engineering works such as the construction of embankments. These disturbances, together with the construction of three small dams in the headwaters, had a direct impact on lateral connectivity by confining and constraining channels and concentrating flows, resulting inchannel incision and stability. The evolution of the disturbances, process changes and geomorphic descriptors indicated that, during the last century, the river channel is in a transient state, in which the magnitude of the changes oscillate. The river is adjusting to the disequilibrium imposed by multi-scale disturbances acting at different temporal and spatial scales by means of two contrasting channel states. First, Channel State 1 (1927–1984) was characterised by having high geomorphic activity and channel incision. Conversely, Channel State 2 (1984–2015) was characterised, by having a low geomorphic activity, when channel constraining was the dominant process and incision was more localised and marginal. The results of the Upper Cinca may be relevant to infer in future fluvial metamorphosis associated with the effects of global change on water and sediment fluxes in mountain catchments, and to assist objective-based rehabilitation measures of rivers subjected to multi-scale disturbances.

Random Naive Bayes (RNB) is a machine learning method that uses the Random Forest (RF) structure to optimize Naive Bayes (NB). It is interesting to see whether RNB could optimize NB and achieve satisfied assessment results like RF in the flood susceptibility assessment study. RNB has rarely been used in study of using machine learning methods to spatially analyze natural disasters, and thus it was selected as the analysis method. Based on the data feasibility, 12 spatial factors that affect the occurrence and spatial distribution of floods were selected. To avoid the influence of subjective equal-interval classification method, natural breaks and quantile method were used to discretize factors with continuous values, respectively. Here, a recently proposed repeatedly random sampling method was adopted to select negative samples for RNB to generate a most accurate classifier (MAC) that was employed to compute the probability of flood occurrence in the study area. Consequently, this paper adopted the integrated framework of GIS and RNB to spatially assess the flood susceptibility using the Wanan County in China as an instance. The results demonstrated that when integrated with the repeatedly random sampling method, the MAC-based flood susceptibility maps corresponding to different factor discretization methods were similar, meaning this framework can effectively avoid the effects caused by different factor discretization methods. Also, to testify the classification performance of RNB, RF and NB were chosen to compare the classification performance with it. The results indicated the classification performance in the order of RF > RNB > NB. This means RNB is able to achieve better classification performance than NB, but it exists limitations when compared with traditional strong classifiers like RF. The findings of this paper proved that RNB is a feasible approach for natural hazard susceptibility assessment.

In an experiment where one of the objectives was to evaluate the effects of slope gradient and rainfall intensity on splash detachment capacity, the authors measured material splashed into slots along the sides of an area eroding by rain-impacted flow. They concluded from their results that their finding was not consistent with previous reports which suggested that splash detachment capacity could be predicted by a power function of rainfall intensity and slope gradient. In rain-impacted flows, a number of transport mechanisms operate in the flow in addition to material transported by splash. Given that only particles that are transported by the transport by splash are considered in the work reported in this paper, the results presented do not give data on how rainfall characteristics and slope gradient influence detachment in raindrop driven erosion. Also, because the transport mechanisms that exist in rain-impacted flow are not 100% efficient, it is not possible to determine detachment by raindrops in rain-impacted flows from the measurement of sediments discharged by splash and surface water flows in experiments like those reported in this paper.

Agricultural terraces are common in mountain regions. They are built to provide a larger surface area for cultivation on hillslopes and to aid farming production in the long term. This paper reviews the hydrological and geomorphological behaviour of constructing, working on and abandoning farming terraces based on recent scientific papers (1982–2014). Terraces increase infiltration and reduce runoff. In Mediterranean areas, the runoff coefficient on abandoned terraces is between 20% and 40%, depending on the percentage of plant cover or the amount of grazing. On cultivated terraces in warm, humid climates, the coefficients are lower (10%–25%). The internal and external sections of terraces have hydrological differences. Soil saturation is reached faster in the inner parts of terraces with shallower soil, causing a rapid hydrological response (saturation runoff); high infiltration rates in external sections can generate subsurface runoff. Furthermore, a reduction in hydrological connectivity, which affects the contributing areas and peak flows, is to be expected in terraced catchments. Collapsed stone walls, small mass movements, sheet wash erosion, piping, rills, gullies and debris flows are all found in terraced landscapes. The erosion of abandoned terraces is directly related to the amount of plant cover, soil characteristics, environmental conditions and the abandonment age. On this type of terrace, the rates of erosion due to overland flow are less than 3 t ha− 1 yr− 1. The rate increases if the terrace is affected by mass movements, pipes or gullies (more than 100 t ha− 1 yr− 1). On cultivated terraces, erosion rates less than 1 t ha− 1 yr− 1 have been recorded for rice crops, and erosion rates greater than 80 t ha− 1 yr− 1 have been recorded for cassava or terraces with bare soil. The scientific literature notes that the soil loss from cultivated slopes is greater if conservation measures, such as terraces, are not included. However, this general result may vary significantly due to factors related to the geo-environmental characteristics of the region and, in particular, the management and use of the terraced slopes., Support for this research was provided by the project INDICA (grant n° CGL2011-27753-C02-01 and CGL2011-27753-C02-02), which was funded by the Spanish Ministry of Economy and Competitivity.

Badlands are highly erodible landscapes with sparse vegetation and rapid runoff responses. Badland surfaces experience high erosion rates that may have a direct and marked influence on river channel networks and catchment scale sediment budgets. Erosion rates from badlands have been widely estimated by discrete observations of topographic change measured by erosion pins or profile meters. Recent developments in survey instrumentation provide the opportunity to build high-resolution topographic models over multiple spatial scales at sub-centimeter accuracy. In this paper we demonstrate how reliable estimates of topographic variables and temporal change can be derived for badlands by repeat Terrestrial Laser Scanning (TLS) surveys undertaken at multiple temporal (event to annual) scales. A total of seven TLS-surveys were obtained in an experimental sub-humid badland located in the Central Pyrenees. Data analyses were conducted on two temporal scales: (a) five rainfall events and (b) three long term (spaced over an annual cycle) scales. Our results show a clear erosional pattern for most of the badland at the annual scale (i.e. annual net change at around − 6 cm yr − 1 ). Aspect, surface roughness and slope were significant predictors of topographic change, although the sign and magnitude of the change differed at the event scale. Net topographic change at the event scale varied from − 1.8 to 1.4 cm. Although these patterns could be also affected by swell-shrink processes, surface roughness was more important at controlling badland geomorphological processes at the event-scale than the annual scale. Our observations suggest that longer-term studies may underestimate the importance of surface roughness as a control on badland geomorphology. At the annual scale the effect of aspect in the sign of the topographic change was removed and slope becomes more important. Erosion proved to be dominant on slopes higher than 100%. Overall, the results indicate that coupling of appropriately-scaled spatial and temporal data is critical to understand topographic changes and their drivers on badlands. Although the approach outlined in this paper was only applied to a relatively small area, with careful survey design and application of new survey technology, it could readily be upscaled to cover entire badland systems. Such surveys would permit detailed analysis of controls of sedimentological connectivity across badlands and their influence on channel networks and catchment sediment budgets.

Geotextiles have been demonstrated to be effective in reducing erosion and subsequent slope degradation processes. However, most studies devoted to assessing the effectiveness of those elements have considered small or intermediate slope gradients (normally ≤ 30°), whereas real engineering works often lead to steeper slopes needing protection. In addition, although a large amount of laboratory studies exist on this topic, there are few articles reporting field experiments which consider large plots, real precipitation and prolonged study periods. This paper is the first of two in which the performance of erosion control geotextiles on steep slopes (45° and 60°) has been assessed. In this paper, the influence of geotextiles on runoff and soil loss reduction was evaluated. The second paper focuses on the effects of geotextiles on the establishment and growth of vegetation on the slope. The research was carried out on an experimental embankment built in Pamplona (Spain) following standard construction procedures in order to resemble real engineering slopes. Two biological geotextiles (jute net and coir blanket) and a synthetic polyester geogrid, installed in two positions (surface-laid and buried), were evaluated and compared with a vegetated hydroseeded control plot. After each significant rain event, runoff and soil loss amounts produced on each plot were recorded. The results showed that coir and jute geotextiles produced 2–3 times larger runoff volumes than the control plots on both the 45° and 60° slopes, whereas the synthetic geogrid did not give significantly different runoff rates from the control (at p

Based on quantitative simulations on the formation and evolution of aeolian dune fields, a semi-analytical equation describing the migration of aeolian sand dunes with respect to dune height, annual wind regime, frictional wind speed, and sand grain diameter is proposed in this paper through analyzing the migration speeds of aeolian sand dunes with different heights in a dune field. The migration speeds of aeolian sand dunes on Earth predicted by the equation is consistent with field observations, and it can be applied to describe the migration of underwater sand dunes and aeolian snow dunes on Earth, as well as that of aeolian sand dunes on other planets, for example Martian sand dunes. In addition, we can also obtain the annual wind regime and the frictional wind speed in dune fields by the A–W method proposed by this paper for given dune speed and sand diameter. It provides a new way to obtain the information of wind field in desert hinterland and on other planets.

The Mogi Guacu River rises in Bom Repouso (Minas Gerais State — Brazil) in the Mantiqueira Ridge, and flows into the Rio Pardo river at an elevation of 483 m in Pontal (Sao Paulo State — Brazil), after running a 530 km long course. Especially along the Lower Mogi Guacu Basin, the river morphology is extremely sinuous, characterized by intense processes of channel migration, avulsion, abandonment and reactivation of the channel, producing an extensive alluvial plain composed of a series of associated relief forms and sedimentary facies. Among these forms, point bar deposits by lateral accretion, abandoned meanders, paleo-channels and fluvial terraces are notable features. In this sense, the objective of this work was to investigate whether these features could be linked to environmental changes. To reach this goal, soil properties of a catena of the Jatai Ecological Station (Luiz Antonio — Sao Paulo State) were analyzed in four sectors: Slope, Terrace I, Terrace II and Alluvial Plain. The results from grain-size determination, geochemical and isotopic studies, dating, paleopalynology, coal fragments and micromorphology are presented in this paper. From these analyses, a paleo-environmental evolution divided in three stages is proposed for the area: 130,000 YBP (Upper Pleistocene), when the Mogi Guacu River base level was approximately 6 m above the present one; a drier second phase 10,250 years BP (Lower Holocene), when an organic horizon was formed inside of an abandoned meander (oxbow lake), and a third phase, 2096 YBP (Upper Holocene), of reactivation of a warm and humid climate that promoted the development of a two meters thick Typic Udifluvent in a sector where the Mogi Guacu River no more floods due to the incision of its thalweg, reaching more than six-meters depth in the last 130,000 years BP. Thus, this paper used a fluvial geomorphologic approach and its interplay with climate to understand how the landscape was shaped from Upper Pleistocene to Holocene, however, Neotectonics might have played a relevant role as well, not only in the Mogi Guacu River Basin, but also in the Parana Sedimentary Basin.

The scientific subjects addressed in the research into badlands since the publication of Bryan and Yair's book (Bryan, R.B. and Yair, A. (Editors), 1982 Badland geomorphology and piping. Geo Books, Norwich, 408 pp.) are briefly analysed. With a steadily increasing number of papers per year, attention to some aspects, such as runoff generation, piping and the role of lithology and soils, varied, whereas the percentage of studies on erosion rates increased steadily over time. Vegetation was not a subject of research in early papers, as most of the papers dealing with vegetation were rather descriptive and published in local or limited-diffusion media, which contrasts with the present situation when about 40% of papers published in international journals about badlands address some aspect of vegetation. However, the growth in the attention paid to vegetation and erosion rates was not linked to any increase in papers dealing with badland reclamation. Badlands are now seen as a group of systems with some common features but diverse dynamics, depending mainly on climatic and lithological drivers. More attention should be paid in the future to investigating the evolution of these landforms over time, mostly through modelling studies, whereas emerging technologies foster detailed analyses that were not possible formerly. Although some badland areas determine on- and off-site environmental issues, others are spots of landscape diversity that merit protection rather than reclamation.

Field scientists studying badland processes in Mediterranean and Semi-arid climates require assurances that the material in which gullies are presented is not dispersive. A dispersive context means; first, infiltration rates may be radically changing in very short periods due to swelling and deflocculation of clays; second, surface crusts could be the result of translocation of sodium into subsurface positions; third, rills may be formed or at least exacerbated by shallow subsurface erosion; fourth, large gullies with substantial up-channel headcuts, including so-called ‘bank gullies’, may have formed because subsurface pipes have collapsed; and fifth, that network connectivity and evolution may be principally internal, being effected by subsurface pipe capture network integration; and most importantly, the bulk of the sediment moving around in the landscape is not being lost from the surface. This paper presents a decision-support tool to assist the effective diagnosis of a landscape's principal genetic process suite. The soil's behaviour in response to its geochemistry in marls with high exchangeable sodium percentages (ESPs) is outlined in simple terms with minimum use of laboratory or field chemical investigations. Using examples the paper then presents a simple set of form indicators that can be used in the field to diagnose the possibility that subsurface process are dominating landscape erosion. Surface crust character, ephemeral rills, and large subsurface tunnel settings are explained and classified. In a final section, the geomorphological implications of piping in gullied landscapes are explored by reference to the literature on connectivity.

Soil and vegetation are interacting factors controlling erosion. Soil degradation processes may affect the normal tree and shrub development and inversely, vegetation can modulate the velocity and intensity of soil development or denudation. A dendrogeomorphological approach can be used to study these interactions, allowing to obtain a date and estimate mean or specific erosion rates. This is especially useful in an unrecorded badlands and gullied environments,where the scarce vegetationmay be the only proxy available to quantify the different geomorphic processes which have occurred. This paper provides a fundamental review of the dendrogeomorphological methodology applied to erosion measurement in badlands. Focusing on the response of the vegetation to the geomorphic processes, this paper: (a) describes themethodology developed to estimate erosion rates with exposed roots; (b) shows newadvances through case studies; and finally, (c) discusses future lines of research to reduce methodological uncertainties and for making dendrogeomorphology more widely applicable.

This paper presents alternating periods of geo-ecological fragility and stability in a highly sensitive environmental setting: the desert-margin area of southern Peru (14.5° S). There, we have to state that fragility was dominantly triggered by climatic changes, which induced several oscillations of the desert margin. During the mid-Holocene, the study area received the Holocene maximum of precipitation, soil formation occurred and the desert retreated, as loess–paleosoil formation documents. In contrast, the Titicaca region further south-east experienced extreme drought at that time. This regional antagonism between humid and dry conditions was a result of meridional shifts in moisture transport across the Andes and occurred also during pre-Columbian times. Considering a coincidence between environmental and cultural changes, we state that success and decline of civilizations were dominated by hydrological oscillations, triggering fertility as well as a critical loss of natural resources. Fragile periods, i.e. periods of geomorphological activity, occurred contemporaneous with cultural transitions. In response to spatial changing resources cultural foci were shifted. So, the success of pre-Columbian civilizations was closely coupled to areas of geo-ecological favorability, which were directly controlled by distinct regional impacts of large-scale circulation mechanisms, including El Nino–Southern Oscillation (ENSO). This spatial view on non-uniform environmental and cultural changes has not been thoroughly considered before. Therefore, for the first time this paper offers geomorphological evidence for diachronous Andean (agri-)cultural development, which was geographically determined .

Soil organic carbon (SOC) dynamics affect soil quality, agricultural productivity and atmospheric CO2 concentration. Despite the need for spatial assessments of SOC content over time, reliable estimates from traditional field survey methods are limited by data availability; where measurements are often made at discrete point locations, at a coarse sample spacing or over a limited spatial extent. Remote sensing (RS) is in a strong position to provide spatially distributed, reproducible, scale-appropriate and resource-efficient measurements of SOC content and fluxes at field, landscape and regional scales. This paper provides a critical review of optical RS techniques for such applications. The first part of the paper reviews the methods, instruments and techniques used for developing predictive models for monitoring spatial SOC content. Secondly, sources of spatio-temporal SOC variations are examined, including the lateral transfer of SOC by erosion, soil structural breakdown and land management practices, in the context of RS data and techniques. The key challenges of using RS to monitor SOC contents are discussed along with opportunities for improving SOC predictions within a spatial framework. Such opportunities include the use of ancillary data, scale-specific methods, improved development of spectral libraries and better integration of RS technologies into empirical and simulation SOC models. This paper aims to provide a transparent assessment and practical guide to RS techniques and products in order to further advance and better incorporate the use of RS methods within soil science.

Conservation prioritization is an important consideration for planning of natural resources management, allowing decison makers to implement management strategies that are more sustainable in the long-term. However, only a current erosion status or a relative index cannot exactly identify priority area for conservation. The objective of this paper is to identify conservation priorities by a specific multicriteria evaluation method. Trends in erosion risk indicate regions of increasing erosion risk and are also chosen as one of the evaluation criteria to identify the priorities based on the instability of soil erosion in the Yongding river basin. In this paper, vegetation cover, land-use, and slope gradient are used to assess erosion risk and trends in erosion risk are obtained by comparing the results of erosion risk between 2000 and 2006. Using this information, the priority conservation areas are graded into six levels. The two highest priority levels cover the regions with severe erosion or a substantial recent increase in erosion risk (4722.56 km 2 , or 11.82% of the study area), and are recommended as erosion control regions with appropriate conservation strategies. The middle two levels cover the regions with stable erosion status or slight change, needing only minor measures. The method presented is fast and straightforward, showing good potential for successful application in other areas.

This paper examines the relations between rainfall, runoff and suspended sediment transport in the Isabena basin during a quasi-average hydrological year. The Isabena is a mesoscale river basin that drains a mountainous area comprising patches of highly erodible materials (badlands). The paper includes an analysis of the different hydrological and sedimentary responses of the catchment to a similar rainfall. Thirty-four floods were studied, with a very variable response observed. Runoff coefficients ranged from 0.32% to 33%. The sedimentary response was also highly variable, with maximum suspended sediment concentrations (SSC) oscillating between < 0.1 and 90 g l− 1 and flood sediment loads varying from 27 to 54,000 t per hydrological event. Most sediment load was concentrated in spring when competent floods occur frequently. Pearson correlation matrix and backward stepwise multiple regression indicate that the hydrological response of the catchment is strongly correlated with total precipitation, event duration, and rainfall of the previous days. Very low correlation was observed with rainfall intensity. The relation between rainfall and sediment transport followed the same trend. Sediment variables (e.g., total load and SSC) were significantly correlated with variables such as total rainfall and rainfall over the previous days, although the significance level was lower in comparison with the runoff related variables. There was again no correlation between sediment variables and rainfall intensity. On-going research in the area suggests that, apart from rainfall, factors such as sediment availability in the badlands and accumulation of sediment in the channels influences the river's sedimentary response. The non-linear hydrosedimentary response is reflected in the wide range of runoff coefficients and sediment loads that have been observed in response to similar amounts of precipitation.

Sedimentological connectivity within drainage systems may be controlled spatially by ‘pockets’ of intact valley fill, alluvial fans impinging laterally on mainstem rivers, floodouts impinging longitudinally on valley floors, and downstream resistant rock bands and their effect on valley width. Where local conditions favor prolonged inundation of the uppermost ~ 0.5 m of the sediment surface, these environments of deposition host wetlands that provide several ecosystem services to society. In this paper, we examine the long-term (millennia), large-scale mediation of connectivity by geological and geomorphological controls, highlighting the relationship between drainage disconnectivity and wetland origin, and appraise ongoing rehabilitation efforts in light of the long-term natural dynamic. The paper uses a wetland system in the KwaZulu-Natal Drakensberg Foothills, eastern South Africa, as a case study, focusing particular attention on part of the system in which cut-and-fill processes are evident, and proceeds, using observations from this and other similar wetland systems in the region, to discuss successive breaks in connectivity with increasing spatial scale and time. Implications for valley morphology are discussed, and channel incision is shown to play an important role in long-term valley and wetland morphodynamics in certain geomorphological settings, creating a diversity of geomorphological features and hydrological regimes. Thus, rehabilitation practitioners should focus on interventions that improve or stabilize desired functional outcomes, rather than on restoring or maintaining what is perceived to be ‘the natural dynamic’ in which erosion is absent.

Southeastern Tanzania serves as a typical example of soil degradation and soil organic carbon (SOC) losses on the African continent. Although sequestration of SOC through aforestation or reforestation proved favorable, these measures are restricted by the ability to produce rapid, cost-effective and precise sampling schemes. The aim of this study is to contribute to a better knowledge of the spatial distribution of soil C in tropical natural and plantation forest. This paper presents sampling strategies for estimating mean SOC values as well as for SOC mapping, based on different methods for SOC determination and on different precision levels. To do so we conducted a carbon variability study in five common forest types of Southeastern Tanzania (coastal dry forest, Miombo woodland, teak plantation, pine plantation and cashew plantation) using conventional statistical methods, as well as geostatistics. In the 5 forest types of this study, SOC stocks in the upper 5 cm ranges between 5 (in the cashew plantation) and 13 (in the coastal forest) t ha− 1. The optimal sampling distance for measuring mean SOC stocks varies between 36 m (in the patchy miombo woodland) and 422 m (in the homogenized cashew plantation). Sample sizes fluctuate between 6 and 72 (1 t ha− 1 precision) for respectively cashew plantation and coastal forest. A rectangular grid with a sample interval of 25 m can be used for SOC mapping with a point kriging estimation error of 3.0 t ha− 1 in the coastal forest, 2.6 t ha− 1 in miombo woodland, 2.2 t ha− 1 in the teak plantation and 1.1 t ha− 1 in the cashew plantation. Since the pine plantation has no spatial structure; samples can be arranged randomly and its best soil map has an average C content attributed over the whole field. Refining the sampling strategy with a new spatial variability study in other forest types can be based on a regular grid with sampling distances of half the range identified in this study. This paper proves that the optimal sampling scheme varies strongly as a result of the different spatial behavior of SOC in forests and depends on the required precision and research question. Only when the right strategy is followed, high standards of precision can be met without economic loss or risk of statistical misinterpretation.

The international symposium ‘HighLand2006’, held in Mekelle (Ethiopia), from 21 to 25 September 2006, was the second time that Ethiopia could host a major international scientific event on geomorphological processes. HighLand2006 created a forum for those conducting research on the impacts of environmental change on geomorphic processes and land degradation in East African highlands as well as in similar regions around the globe. Discussions of results and exchange of experiences during indoor sessions as well as excursions have resulted in this distinctive set of scientific papers. The two main questions addressed in this special issue, through case studies in tropical mountain areas on all continents are: 1. How have environmental changes impacted the type and intensity of geomorphic processes in tropical mountains since late Pleistocene times? The answer to this question is strongly linked to our knowledge on changes in climate, vegetation cover, human activities, hydrology, hillslope and fluvial processes for such environments. 2. Which factors control the intensity of land degradation, its on-site and off-site impacts in tropical mountains? This question addresses the role of natural and anthropogenic factors in the degradation of the vegetation cover and in controlling the intensity of hydrological processes, soil erosion, landsliding, reservoir sedimentation and flooding. In parallel with this special Catena issue, a number of selected papers on land degradation and its mitigation in tropical highlands are presented in a special issue of Soil & Tillage Research.

This paper reviews recent changes in river management. These changes are characterised by a move from the notion of rivers as stable equilibrium forms to one of dynamic responsive ecosystems. Coupled to these changes are a series of scientific questions that provide the context for reviewing the role that palaeohydrology might have in supporting contemporary and future river management. Palaeohydrology is shown to be capable of providing important and relevant information to river managers. Furthermore a series of emerging frameworks for incorporating geomorphology in river management exist wherein palaeohydrological data and analysis can be directly interfaced with the river management process. The paper therefore concludes that within specific limits, palaeohydrology is in much stronger position to support and communicate with the river management agencies than has previously been the case.

This paper reports on the development of a British database of 14C dated Holocene fluvial units over the last 15 years. Since its inception in 1989, the database has undergone substantial expansion, refinement and improvement together with considerable methodological development, so that today it serves as a powerful research tool for investigating the spatial and temporal dynamics of Holocene river development and flooding in Great Britain. The improved analytical method is here applied to the currently existing database by examining datasets of 14C dated fluvial units from river basins that lie within and beyond the limits of Late Devensian glaciation. This analysis indicates how the contrasted conditions in these two types of river environment have, to an extent, led to divergent records of flooding in response to Holocene climate and land-use change. However, even in the contrasting sedimentary records of upland glaciated, and lowland unglaciated river basins, six corresponding episodes of increased flood frequency are identified at c. 5730, c. 3540, c. 2730, c. 2280, c. 660 and c. 570 cal. BP. These represent widespread common responses from British river systems to large-scale changes in climate. The method of database construction and analysis outlined and demonstrated in this paper could be readily adopted in other parts of the world to improve our understanding of Holocene river behaviour at the continental- and global-scale.

This paper investigates the influence of rainfall intensity and initial soil water content on changes in the near-surface soil hydraulic conductivity. While numerous papers have examined surface sealing, this paper outlines two important innovations: the design and application of time-domain reflectometry probes with the ability to measure and record soil water content at very short time and length scales; the design and application of stainless steel tensiometers to measure soil water potential at the same, very short, time and length scales. These permit the Richards Equation to be applied and the near-surface hydraulic conductivity computed. An exponential curve was fitted to the temporal changes in hydraulic conductivity, as both a function of water potential or soil water content, with a high degree of fit. As rainfall intensity increased, the degree of scatter about the best-fit line increased, probably due to the ability of high intensity rainfall to disrupt the near-surface soil structure. While utilising deterministic models, such as the Richards Equation, may be appropriate at the column scale there are practical difficulties due to the very small length scale variability in each of the input variables. The experimental results detailed here indicate that even with data at very short time and length scales it is still not possible to utilize the Richards Equation, or at least, it may be difficult to transfer the laboratory results to the field due to the effect of the specific laboratory experimental conditions on the results.

The Unit Hydrograph (UH) technique is widely used for runoff estimation, especially for determining peak discharges. In this paper, a geomorphologically based UH has been applied. Its most remarkable characteristic is that it includes the watershed structure in its formulation. This is defined from the drainage network, each subwatershed being considered as a linear reservoir. In this method, the fact of considering this reservoir sequence according to the drainage network leads to the formulation of the model only depending on a single parameter. The Geomorphological Unit Hydrograph of Reservoirs (GUHR), proposed in this paper, is compared with Nash's Instantaneous Unit Hydrograph (Nash's IUH), by applying the two methods to the Aixola watershed. This 4.7-km2 watershed is located in Gipuzkoa (Northern Spain). It is characteristic of the headwaters watersheds of the area. Most of them are forested and have steep slopes. Annual rainfall is over 1500 mm and many intense rainfall events are observed, among which 18 were selected for this study. Both UH techniques were applied to the rainstorms. The resulting hydrographs were plotted against registered data and the best fits were determined. According to these results, the GUHR model behaved similarly to Nash's IUH. However, the GUHR method seemed able to reproduce a wider range of rainstorms than Nash's IUH. While analyzing the UHs calculated, seasonal behavior was observed in runoff generation, and different average UHs were proposed for two different periods. This variability was also observed in values adopted by the GUHR model parameter, providing some information about the watershed time response. The dynamic character of the only uncertain parameter, and the model formulation, in which the watershed morphology is reflected, together with the model's simplicity, leads us to consider GUHR as being a promising UH model.

This paper describes the use of geomorphologic knowledge for resource management in rural areas of less developed countries. Specifically, we discuss the contribution of geomorphologic mapping (coupled with landscape knowledge) to natural resource management using geographic information systems (GIS) and remote sensing techniques. We describe a case study conducted at Nuevo San Juan Parangaricutiro, an indigenous forest community in the Paricutin area, in Michoacan, Mexico. The analysis described in this paper was used to improve the mapping of forest quality units, and to explore the relationships between land suitability and land utilisation requirements for potential diversification of economic activities in the indigenous community. The approach proved useful for the management of natural resources and was made operational by the actual managers of the resources. The community of Nuevo San Juan was granted the green certification (Smart Wood) by the Forest Stewardship Council (FSC) and produced a fully automated resource management plan.

Hummocky ground is a conspicuous feature of some cultivated pastures in the mountain forests of the Alps. In the German scientific literature, this pit and mound microrelief is termed “Buckelwiese” (literally: “hummocky meadow”) and is commonly interpreted as a fossil, Late Glacial relief of cryogenic origin. This paper suggests an alternative hypothesis, namely that relief formation was initiated by the uprooting of trees during storms. In the rootstock-pits, karst processes gradually amplified the initial relief. This alternative hypothesis is tested in a Buckelwiesen area of the Northern Limestone Alps, where pit-to-mound vertical relief amounts to 52 cm and mounds are 250–510 cm long and 170–270 cm wide, and the density of pits and mounds is 400 ha −1 . Field investigations included a ground survey using a tacheometer and the excavation of a trench to check the internal structure of one pit-mound couple. The trench was subsequently used to estimate solution rates in the subsurface material of pits and mounds. Based on the results of the field measurements and two radiocarbon dates from the test site, the paper concludes that in the study area a treethrow event occurred between 1120 and 1280 AD. Subsequently, the pits created by the uprooted trees were deepened by limestone solution at a rate of 77.2 mm/1000 years. The reconstructed formation history of the microrelief of the study area is consistent with a Holocene origin, with rates of limestone dissolution as measured in the field and with the morphometry of the features themselves.

More than half a million soil science papers have been published since the 1920s. In addition, a large number of books are being published. This paper focuses on the seven major soil reference books that were published between 2000 and 2012: Handbook of Soil Science (2000 and 2012), Encyclopedia of Soil Science (2002 and 2006), Encyclopedia of Soils in the Environment (2005), Encyclopedia of Soil Science (2008), and Soil Science — Reference collection (2009). These soils science reference books contain 1920 articles (12,295 pages) authored by some 2000 authors. The Handbook of Soil Science covers the basic subdisciplines (physics, chemistry, biology, pedology) most extensively whereas the encyclopedia have more applied entries/articles. Overall, these intradisciplinary reference works show that the soil science discipline is vibrant and has a rapidly expanding knowledge base.

A large number of studies have focused on water erosion in the southern Alps because of its intensity and the high erodability affecting numerous outcrops in this region. The aim of this paper is to determine the relations between natural and human factors on the one hand, geomorphologic behaviour of hillslopes and fluvio-torrential dynamics at two time scales (geological and historical) on the other hand. This paper specially focuses on the recent weakening of torrential activity and its linkage with reforestation and rural desertion on the watersheds. Another objective is to compare these results with a rich mainly French scientific production on this theme. Experimental data on: – current erosion measurements and the analysis of its processes on the one hand, – and geomorphologic background of river beds and slopes, are compared and analysed using archives and the present knowledge on historical climate. It has been shown that the overexploitation of watersheds leads to an increase in soil loss, in the number and intensity of floods in alpine valleys, as well as to an enhancement of sediment transport. However, climatic changes during the Holocene and during the past millennium have resulted in changes in morphological behaviour of the hillslopes upstream and of river beds downstream. Moreover, a strong sedimentary deficit can be observed over the last three or four decades in all the Alpine massifs. The consequences of this sediment deficit are firstly an entrenchment of river beds, which threatens bridges and embankments. This recent trend is probably due to the excessive extraction of material in gravel pits and the sedimentation in the numerous dams built between 1920 and 1980 in the entire alpine range. However, the entrenchment appeared recently on non-exploited rivers; therefore, the deficit is also due to the success of the natural and artificial reforestation and torrent correction since the end of 19th century.

Interactions between soil surface properties, water runoff and erosion occur at many time and space scales. The paper focuses primarily on the effects of soil microtopography at a range of spatial scales and considers some new conceptual approaches to modelling its effect on runoff generation, flow concentration and sediment transport. In this paper, the local generation of runoff is considered through the simplifying concept of a discrete runoff threshold. The effect of random roughness is considered independently in the down-slope and cross-slope directions. Roughness elements measured in the cross-slope direction concentrate the flow within depressions, and create greater total sediment transport. Roughness measured in the down-slope direction represents elements which pond or impede the flow, reducing mean flow velocity and reducing sediment transport. This two-component approach to roughness provides a reasonable approximation to behaviour on fractally generated two-dimensional surfaces. If the roughness elements are assumed to be normally distributed, and independently random in the two directions, then explicit integrations can be made over the distributions, providing significant corrections to the relationship between mean flow depth and sediments transporting capacity. A second conceptual model is presented, exploring the implications of spatially random variations in surface flux capacity (storm total infiltration), surface (depression) storage and storm rainfall totals. It is demonstrated that some at-a-point runoff may, in principle, be generated, even where surface capacity appears to greatly exceed storm rainfall. In conclusion, it is argued that these effects, together with others not covered here, should be included in the next generation of soil erosion models.

The predicted rise in sea level due to global warming has given rise to much speculation as to the impact on erosion and accretion rates at the coast as well as increases in hazards to coastal users. This paper focuses on the spatial adjustments that coastal landforms will exhibit in response to changing energy gradients both normal to and parallel to the shore. These adjustments, in many cases, will take the form of the migration of landforms in order that they maintain their position within the coastal energy gradient. Prediction of the rates of such migration will be fundamental to the future management of the changing coastal environment. The paper discusses the impact of sea-level rise on the two basic coastal landform assemblages: those in estuaries and those on the open coast, and then goes on to examine the effect on ebb-tidal deltas that are located at the critical junction between estuaries and open coasts. In each case, the rates of landform migration under an accelerated sea-level rise are predicted and compared with existing rates using examples from the east coast of Britain. Assuming a sea-level rise of 6 mm/year, the paper predicts that estuaries will migrate landwards at rates of around 10 m/year, open-coast landforms can exhibit long-shore migration rates of 50 m/year, while ebb-tidal deltas may extend laterally along the shore at rates of 300 m/year. The implication for the management of such dynamic coastal systems, including such issues as coastal defence and conservation, are discussed.

Erosion of farmland due to concentrated flow is very severe on many unprotected fields across the United States. Small channels can turn into large gullies if not controlled. These small channels are routinely obliterated by tillage of the field and other routine farm operations only to be reformed again. Opposing slopes adjacent to an ephemeral gully allow runoff to reestablish a channel in approximately the same location. Since the 1960s, the Universal Soil Loss Equation (USLE) has been used to estimate rill and sheet erosion. This paper describes the Ephemeral Gully Erosion Model (EGEM). EGEM is a modification of the Agricultural Research Service Ephemeral Gully Erosion Estimate (EGEE) computer model to meet the Natural Resources Conservation Service (NRCS) needs. Limited field data obtained by NRCS were used to validate the single event component of EGEM. This paper presents a summary of these studies. There were no data available at the time of the model development to validate the average annual concept of the model. ARS conducted validation studies for the EGEE model.

This paper details a basic method for estimation of both bed material yield and supply rates for a glaciated catchment. Recent research has illustrated the potential of morphological methods for the estimation of bed material transport rates, but also raised important methodological issues, notably regarding the requisite spatio-temporal resolution of morphological data and the need for either information on upstream sediment supply or assumptions about typical distances of particle movement during transport. Both of the latter have proved problematic. This paper provides an additional means of estimating bed material transport rates and yields through the combination of a simple process-based relationship with morphological information. For a short reach of gravel-bed stream, in a glaciated catchment with a characteristic diurnal discharge hydrograph, a strong positive relationship was found between the volume of water passing through the reach and the volume of erosion in the reach, for points early on the rising limb of the hydrograph. This relationship broke down later in the hydrograph, notably after the discharge peak, associated with the advent of sediment supply from upstream. Thus, early in the hydrograph, this relationship provides an indication of the capacity of this reach to move sediment, either locally eroded material or sediment supplied from upstream, and this paper applies this relationship to a six week discharge hydrograph to predict the potential transport volumes. From these predictions, it calculates the minimum volume of bed material that must have been supplied to the reach from upstream, per hour, to maintain its observed elevation. The results are used to illustrate and discuss some of the problems associated with the use of morphological information for the estimation of bed material transfer rates.