A New European Slope Length and Steepness Factor (LS-Factor) for Modeling Soil Erosion by Water

The Universal Soil Loss Equation (USLE) model is the most frequently used model for soil erosion risk estimation. Among the six input layers, the combined slope length and slope angle (LS-factor) has the greatest influence on soil loss at the European scale. The S-factor measures the effect of slope steepness, and the L-factor defines the impact of slope length. The combined LS-factor describes the effect of topography on soil erosion. The European Soil Data Centre (ESDAC) developed a new pan-European high-resolution soil erosion assessment to achieve a better understanding of the spatial and temporal patterns of soil erosion in Europe. The LS-calculation was performed using the original equation proposed by Desmet and Govers (1996) and implemented using the System for Automated Geoscientific Analyses (SAGA), which incorporates a multiple flow algorithm and contributes to a precise estimation of flow accumulation. The LS-factor dataset was calculated using a high-resolution (25 m) Digital Elevation Model (DEM) for the whole European Union, resulting in an improved delineation of areas at risk of soil erosion as compared to lower-resolution datasets. This combined approach of using GIS software tools with high-resolution DEMs has been successfully applied in regional assessments in the past, and is now being applied for first time at the European scale.JRC.H.5-Land Resources Managemen

Sustainable Land Use Planning Model in Rural Basins

Soil erosion is a common problem that complicates watershed management in Turkey and around the world. The main objective of soil conservation work carried out in basins is to ensure sustainable watershed management. The first operation is to define the current situation in the basin. The initial and fundamental objective of erosion estimation based on existing data is generally deciding how to overcome the problem. However, the treatments carried out in most soil conservation studies are similar to each other. Any common, known, or defined methodology about erosion problems in watersheds has not been improved—until now. Considering this problem, the Sustainable Land Use Planning (SLUP) model was developed to determine soil conservation precautions, to set priorities for decision makers and to produce a common solution for rural watershed in Turkey. While the estimated average soil loss was determined to be 7.66 t ha−1 per year, some land use changes were proposed and land use management priorities were set in the direction of the model results to gain sustainable management in the Çelikli basin. At the end of the study, it was showed that the soil loss can be reduced about the rate of 91.2% applying the SLUP model

Evaluation of erosion risk map based on hierarchical decision tree method, a case study: Semnan drainage basin

Introduction: Today, Soil erosion has become one of the biggest problems in the country, especially in arid and semi-arid including Semnan. Effective and long term water and soil conservation programs require the concentration of resources on limited areas. For that purpose, regional-scale assessments of erosion risk are required. There are various methods to studying, evaluating, calculate and prevention with soil erosion. In addition, a number of parameters such as lithology, slope, aspect, land cover, elevation, and distance to stream, drainage density, vegetable cover, land use, river banks, and human activities are recommended to analyze the mechanism of soil erosion. So a rapid and cost effective methodological erosion assessment for these regions is required to describe and monitor the processes that control erosion. This study uses one of the remote sensing analyses to describe the contribution of several factors that control erosion in Semnan drainage basin where erosion is the major environmental problem. Remote sensing monitoring has been carried out by using aero photos, or multispectral images, DTM (Digital Terrain Model) or ALS (Airborne LASER Scanning) data. Semnan basin, study area, is located in north of Kavir plain and south of Alborz mountain range. Methodology: This study was conducted to evaluate the potential of analyzing regional erosion risk Topography, land use; vegetation density, soil properties and climatic proxies are used to determine erosion risk and to provide basic maps of water and soil conservation practices. A hierarchical decision tree is used to sum and combine the weight of parameters controlling the erosion. The assigned weights of each spatial unit express the susceptibility to erosion. The most important attributes in the definition of erosion landforms like gullies were selected using decision tree induction algorithms, being these attributes spectral, altimetry and texture. Classifications hierarchical and by decision trees were carried out. Using decision tree the classification is performed only by a factor of scale, not allowing the identification of all the constituent features of the erosion landforms system. One of the advantages of this method is that it can be used if there are insufficient experimental data. The lack of experimental data can be compensated for through the use of expert evaluations. Results and discussion: Three different combinations of the three dominant controlling factors are yielded in this study. In order to optimize the qualitative erosion risk assessment, each combination is discussed and evaluated depending on the contribution of parameters involved in the erosion process. As different erosion landforms erosion is similar when presents the same evolution stage and soil type, it is not possible to select attributes to classify all erosion landform systems, being necessary to investigate attributes for each erosion landform erosion, based on available data and existing land use classes in the area. The erosion landforms are the biggest erosive processes and, consequently, responsible for ambient, social and financial damages. Corrective and preventive measures need mapping and monitoring, which can be made by local measurements or by remote sensing. In relation to the remote sensing, the erosion landform erosion presents spectral heterogeneity (soil, vegetation, shade and water mix), spatial heterogeneity (existence of features as head, canals and digits with irregular forms and variable dimensions) and altimetry variation (with high declivity on the edges). Due to spectral heterogeneity, it is not enough use only spectral data, being necessary auxiliary data, as altimetry and texture data. This clearly shows that the study area is generally exposed to a high hazard of soil erosion. Nevertheless, there is a probability that the rate of erosion will increase in the future, as hazard is the probability of occurrence of a potential damaging phenomenon, within a period of time and a given area. As known, there is always an interest to depend on latest developments when making subjective judgments. In spite of the results obtained in this study, the development of a susceptibility map is usually determined by the needs and available resources, and AHP method can be equally important for all sorts of susceptibility zoning practices. Conclusion: The purpose of this study was to assess the soil erosion hazard in the Semnan province for planning appropriate conservation measures. The integrated GIS-AHP model was used to define spatial distribution of soil erosion hazard. In this area, erosion risk mainly was related with vegetation and also, it anticipated that the southern and south-eastern region due to the poverty of vegetation associated with increased levels of erosion. In each of the three mapped models, the area of the class with high erosion sensitivity was more than 75% and for observational data, the area in all three maps is above 71%. Also, the results of the assessment show that in all three maps there are over 99% correlation between the data obtained from the modeling and the test data. The erosion landforms present spectral and spatial heterogeneity and altimetry variation. This research demonstrates that the model developed was an effective tool for fast assessment of soil erosion hazard by the integration of remote sensed data, AHP, and GIS techniques. Nevertheless, the results obtained in this study are valid only for generalized planning and assessment purposes. They may be less useful at the site-specific scale, where local geological and geographic heterogeneities may prevail. Finally, any proposed decision-making tool in erosion control studies should also include local experimentation data to better simulate the erosion hazard, resulting thereby in the most appropriate and efficient choice of soil conservation works

Soil Erosion

In the first section of this book on soil erosion, an introduction to the soil erosion problem is presented. In the first part of the second section, rainfall erosivity is estimated on the basis of pluviograph records and cumulative rainfall depths by means of empirical equations and machine learning methods. In the second part of the second section, a physically-based, hydrodynamic, finite element model is described for the computation of surface runoff and channel flows. In the first part of the third section, the soil erosion risk is assessed in two different basins. In the second part of the third section, the soil erosion risk management in a basin is evaluated, and the delimitation of the areas requiring priority planning is achieved

Settlement land management based on land capability in Batu City

Urban expansion occurs in big cities in Indonesia, including Batu City. An increase in the built-up area occurred in Batu City by 554.4 ha or 2.78%, and a decrease in agricultural land by 341.1 ha occurred in 2008-2018. If the Batu City government does not pay attention to the availability of environmental services or consider the geomorphological conditions of Batu City for developing settlements. In that case, it will have an environmental impact. The environmental problem in Batu City during the 2009-2019 period was an increase in greenhouse gases by 0.75% per year. Batu City is located in a hilly area. It is necessary to explore land capability in Batu City so that land use planning follows its environmental services and is sustainable. This study aimed to determine the land capability for settlements in Batu City based on the Regulation of the State Minister for the Environment Number 17 of 2009 concerning Guidelines for Determining Environmental Supporting Capacity in Regional Spatial Planning. This study used a geographic information system (GIS) and ArcGIS 10.8 software. The method used was overlapping soil texture, slope, drainage, effective soil depth, erosion, and flood potential maps. Batu City has a slope of 30-45% and a total area of 6,581.03 ha or 33% of the area of Batu City. The largest erosion rate reached 10,326.33 ha or 52% of the total area of Batu City. Erosion occurs on land used for agriculture or moorland. Soil protection and erosion control measures are strongly recommended. The area around Batu City, 1,174.28 ha, experienced considerable erosion, and 2,631.62 ha of land in Batu City is used for settlements. Land capability analysis can determine the starting point or basis for settlement land management in Batu City, which has a slope of more than 15%. There are only 461.9 ha of land management for settlement which follows the regional spatial planning and land capability in Batu City, spread over three different districts

Avaliação da abordagem hidrossedimentológica em planos de recursos hídricos no Rio Grande do Sul

A Lei Federal nº 9.433/1997, também conhecida como Lei das Águas, instituiu no país a Política Nacional de Recursos Hídricos (PNRH); dentre os cinco instrumentos da PNRH, os Planos de Recursos Hídricos se destacam. Eles são, em resumo, planos diretores que objetivam fundamentar e orientar a implementação desta Política, analisando as condições atuais das bacias hidrográficas e estabelecendo projeções e metas futuras. Também buscam analisar as modificações nos padrões de uso e ocupação dos solos e a concepção de metas de melhorias de qualidade das águas. Todos estes conteúdos estão intimamente conectados ao tema “hidrossedimentologia”, porém a abordagem deste tema nos Planos atualmente é fragmentada e, em alguns casos, escassa. Motivado por esta questão, o objetivo geral do presente trabalho é o de estabelecer um panorama da abordagem hidrossedimentológica adotada nos Planos de Recursos Hídricos frente aos desenvolvimentos científicos mais modernos na área, tendo como estudo de caso os PRHs elaborados no Estado do Rio Grande do Sul. A metodologia aplicada foi dividida em duas etapas: na primeira foram analisados os Planos de Bacia já disponíveis para a área de estudo, no que tange a avaliação da perda de solos e da produção de sedimentos nestes estudos. Na segunda etapa, foram identificadas as metodologias mais comumente utilizadas na literatura científica para a abordagem da temática hidrossedimentológica baseada em uma busca realizada na base de dados Scopus. Após, as metodologias identificadas nas duas etapas (PRHs e trabalhos científicos) foram analisadas e comparadas. Os resultados obtidos demonstram que os Planos de Bacia utilizam, em sua maioria, a USLE para estimativa da perda de solos potencial, e junto a esta aplicam uma Taxa de Transferência de Sedimentos para obtenção da produção de sedimentos. Dos PRHs disponíveis para a área de estudo, apenas 65% avaliam a perda de solos, e 53% quantificam a produção de sedimentos. Em comparação com a literatura científica, dos 243 artigos avaliados, 44% destes aplicam o modelo SWAT (Soil and Water Assessment Tool), seguido pela utilização do modelo WEPP (Water Erosion Prediction Project) em 20 trabalhos. Conclui-se que as metodologias aplicadas nos Planos de Recursos Hídricos para o Estado do Rio Grande do Sul geram resultados inferiores – menos precisos – aos métodos utilizados em artigos científicos. Enquanto grande parte dos resultados nos PRHs permitem quantificar a produção de sedimentos apenas por eventos e em pontos localizados da área de estudo, as metodologias mais comumente empregadas na literatura científica geram séries históricas de dados, podendo ser obtidas e analisadas informações para diversos locais da bacia hidrográfica. Assim, a lacuna gerada pela falta de análises mais robustas em grande parte dos PRHs estudados acaba por dificultar que o Plano de Bacia gere conclusões mais apuradas quanto às características qualiquantitativas dos cursos d’água no que tange ao conhecimento hidrossedimentológico, ocasionando até mesmo uma maior fragilidade em relação a diagnósticos e proposições relacionados ao uso e ocupação do solo da bacia hidrográfica.The Federal Law Nº 9.433/1997, also known as the Water Law, established the National Water Resources Policy (NWRS) in Brazil. Among the five instruments of the NWRS, the Water Resources Plans stand out. Briefly, they are master plans that aim to support and guide the implementation of this Policy, analyzing the current conditions of the river basins and establishing future projections and goals. They also seek to analyze changes in land use and occupation patterns and the design of water quality improvement targets. All these contents are closely connected to the topic “hydrosedimentology”, however the approach to this topic in the Plans is currently fragmented and, in some cases, scarce. Motivated by this question, the general objective of this work is to establish an overview of the hydrosedimentological approach adopted in the Water Resources Plans considering the most modern scientific developments in the area, taking as a case study the Plans published in Rio Grande do Sul state. The methodology applied was divided into two stages: first, the Basin Plans already available for the study area were analyzed, regarding the assessment of soil loss and sediment production in these studies. In the second stage, the methodologies most used in scientific literature to approach hydrosedimentology were identified – based on a search carried out in the Scopus database. Afterwards, the methodologies identified in the two stages (Basin Plans and scientific works) were analyzed and compared. The results obtained demonstrate that the Basin Plans mostly use USLE to estimate potential soil loss, and together with this they apply a Sediment Delivery Ratio to obtain sediment production. Of all Water Resources Plans available for the study area, only 65% assess soil loss, and 53% quantify sediment production. Compared with the scientific literature, of the 243 articles evaluated, 44% of them apply the SWAT model (Soil and Water Assessment Tool), followed by the WEPP model (Water Erosion Prediction Project) in 20 works. It is concluded that the methodologies applied in the Water Resources Plans for the Rio Grande do Sul state generate inferior results – less accurate – to the methods used in scientific articles. While most of the results in Basin Plans allow quantifying sediment production only by events and at localized points in the study area, the methodologies most used in scientific literature generate historical data series, allowing information to be obtained and analyzed for different locations in the watershed. Thus, the gap generated by the lack of more robust analyzes in a large part Water Resources Plans ends up making it difficult for these Plans generate more accurate conclusions regarding the qualitative and quantitative characteristics of the watercourses – in terms of hydrosedimentological knowledge, even causing a greater fragility in relation to diagnoses and propositions related to the use and occupation of soil in the watershed

Evaluating Differences of Erosion Patterns in Natural and Anthropogenic Basins through Scenario Testing: A Case Study of the Claise, France and Nahr Ibrahim, Lebanon

This study assessed soil erosion risks of two basins representing different geographical, topographical, climatological and land occupation/management settings. A comparison and an evaluation of site-specific factors influencing erosion in the French Claise and the Lebanese Nahr Ibrahim basins were performed. The Claise corresponds to a natural park with a flat area and an oceanic climate, and is characterized by the presence of 2179 waterbodies (mostly ponds) considered as hydro-sedimentary alternating structures, while Nahr Ibrahim represents an orographic Mediterranean basin characterized by a random unequal land occupation distribution. The Claise was found to be under 12.48% no erosion (attributed to the dense pond network), 65.66% low, 21.68% moderate and 0.18% high erosion risks; while Nahr Ibrahim was found to be under 4, 39.5 and 56.4%, low, moderate and high erosion risks, along with 66% land degradation determined from the intersection of land capability and land occupation maps. Under the alternative scenario for the Claise where ponds were considered dried, erosion risks became 1.12, 0.52, 76.8 and 21.56%, no erosion, low, moderate and high risks, respectively. For Nahr Ibrahim, and following the Land Degradation Neutrality intervention, high erosion risks decreased by 13.9%, while low and moderate risks increased by 3 and 10.8%

SOIL CONSERVATION TECHNIQUES AND PRODUCTIVITY OF ARABLE CROP FARMERS IN KOGI STATE, NIGERIA

The study examined soil conservation techniques and its effect on productivity of arable crop farmers in Kogi state, Nigeria. Data were collected from 184 farmers using three stage sampling technique.  Data analyses were carried out using descriptive statistics, Total Factor Productivity (TFP) and regression analysis. Result shows that the soil conservation technique prevalent in the area was application of inorganic fertilizer. About 36.4% of the sampled household heads have productivity value above average across all the soil conservation categories (productive). Result also reveals that age (-1.801), household size (-0.310) and access to credit (-0.056) impacted arable crop farmers negatively while alley cropping (0.357), crop rotation (0.380), application of inorganic fertilizer (0.503), mulching (0.560) and organic manure (0.373) positively impacted arable farmers’ productivity.  The study concludes that soil conservation techniques are productivity enhancer. Promoting sustainable conservation techniques that are farm or farmer specific is recommended.   &nbsp

Modelling weed management effects on soil erosion in rubber plantations in Southwest China

Land use in Xishuangbanna, Southwest China, a typical subtropical rain forest region, has been dramatically changed over the past 30 years. Driven by favorable market opportunities, a rapid expansion of rubber plantations has taken place. This disturbs forests and land occupied by traditional swidden agriculture thus strongly affecting hydrological/erosion processes, and threatening soil fertility and water quality. The presented PhD thesis aimed at assessing farmer acceptable soil conservation strategies in rubber plantations that efficiently control on-site soil loss over an entire rotation time (25 40 years) and off-site sediment yield in the watershed. The study started with field investigations on erosion processes and soil conservation management options in rubber plantations (Chapter 2 and 3). Based on the field data, the physically based model Land Use Change Impact Assessment (LUCIA) was employed to assess long-term conservation effects in rubber plantations (Chapter 4) and scale effects on sediment yield in the watershed (Chapter 5). Specifically, the first study aimed at assessing soil loss in rubber plantations of different ages (4, 12, 18, 25 and 36 year old) and relating erosion potential to surface cover and fine root density by applying the Universal Soil Loss Equation (USLE) model. This study adopted the space-for-time substitution for field experimental design instead of establishing a long-term observation. Spatial heterogeneity of soil properties (e.g. texture, organic carbon content) and topography (slope steepness and length) interfered erosion at different plantation ages. To meet this challenge, namely account for possible impacts of soil properties and slope on erosion, the empirical USLE model was applied in data analysis to calculate the combined annual cover, management and support practice factor CP, which represents ecosystem erosivity. Calculated CP values varied with the growth phase of rubber in the range of 0.006 - 0.03. Surface cover was recognized as the major driver responsible for the erosive potential changes in rubber plantations. The mid-age rubber plantation exhibited the largest erosion (3 Mg ha-1) due to relatively low surface cover (40%-60%) during the rainy season, which was attributed to low weed cover (below 20%) and the low surface-litter cover favored by a high decomposition rate. Based on the results of the first study, the second study focused on reducing soil loss in rubber plantations by maintaining a high surface cover through improved weed management. Among the different weeding strategies tested, no-weeding most efficiently reduced on-site soil loss to 0.5 Mg ha-1. However, due to the low farmer acceptance of the no-weeding option, we recommend reducing herbicide application to a single dose at the beginning of the rainy season (once-weeding) to better conserve soil as well as inhibiting overgrowth of the understory vegetation. As the second experiment lasted only one-year, while rubber plantation is a perennial crop with a commercial lifespan of 25 40 years, the third study applied the LUCIA model to simulate the temporal dynamics of soil erosion in rubber plantations under different weeding strategies. The erosion module in LUCIA was extended to simulate both runoff and rainfall based soil detachment to better reflect the impact of the multi-layer structure of the plantation canopy. The improved LUCIA model successfully represented weed management effects on soil loss and runoff at the test site with a modelling efficiency (EF) of 0.5-0.96 and R2 of 0.64-0.92. Long-term simulation results confirmed that once-weeding controlled annual soil loss below 1 Mg ha-1 and kept weed cover below 50%. Therefore, this weeding strategy was suggested as an eco- and farmer friendly management in rubber plantations. Furthermore, LUCIA was applied at watershed level to evaluate plot conservation impact on sediment yield. Two neighboring sub-watersheds with different land cover were chosen: one a forest dominated (S1, control), the other with a mosaic land use (S2), which served to assess mono-conservation (conservation only in rubber plantations) and multi-conservation (conservation in maize, rubber and tea plantations) effects on total sediment yields. The model was well calibrated and validated based on peak flow (EF of 0.70 for calibration and 0.83 for validation) and sediment yield (EF of 0.71 for calibration and 0.95 for validation) measured from the two watersheds outlet points. Model results showed that improved weed management in rubber plantations can efficiently reduce the total sediment yields by 20%; while multi-conservation was largely able to offset increased sediment yields by land use change. In summary, while exploring the dynamics of erosion processes in rubber plantations, a physically based model (LUCIA) was extended and applied to simulate weed management effects over an entire crop cycle (40 years) and implications at higher scale level (watershed sediment yield). Once-weeding per year was identified as an improved management to reduce on-site erosion and off-site sediment yield. But to fully offset increased sediment yield by land use change, a multi-conservation strategy should be employed, which not only focuses on new land uses, like rubber plantations, but also takes care of traditional agricultural types. A conceptual framework is proposed to further assess the specific sub-watershed erosion (e.g. sediment or water yield) effects in large watersheds by spatially combining process-oriented and data-driven (e.g. statistic based, machine learning based) models. This study also serves as a case study to investigate ecological issues (e.g. erosion processes, land use change impact) based on short-term data and modelling in the absence of long-term observations.Die Landnutzung in Xishuangbanna, Südwestchina, einer typischen subtropischen Regenwaldregion, hat sich in den letzten 30 Jahren dramatisch verändert. Getrieben von günstigen Marktchancen hat ein rapider Ausbau von Kautschukplantagen stattgefunden. Dies beeinflusst Wälder und Flächen, die durch traditionellem Brandrodungsackerbau bewirtschaftet werden, was starke Auswirkungen auf hydrologische Prozesse und Erosionsprozesse hat und die Bodenfruchtbarkeit und Wasserqualität bedroht. Die vorliegende Dissertation zielte auf die Bewertung von akzeptablen Bodenschutzstrategien für Landwirte in Kautschukplantagen ab, die den Bodenverlust innerhalb des Standortes während einer ganzen Rotationszeit (25 - 40 Jahre) und den Sedimentausstoß außerhalb des Standortes im Wassereinzugsgebiet effizient kontrollieren. Die Studie begann mit Felduntersuchungen zu Erosionsprozessen und Bodenschutz-Managementoptionen in Kautschukplantagen (Kapitel 2 und 3). Basierend auf den Felddaten wurde das physikalisch basierte Modell "Land Use Change Impact Assessment" (LUCIA) eingesetzt, um Langzeitschutzeffekte in Kautschukplantagen (Kapitel 4) und Skaleffekte auf den Sedimentausstoß im Wassereinzugsgebiet zu bewerten (Kapitel 5). Konkret zielte die erste Studie darauf ab, den Bodenverlust in Kautschukplantagen unterschiedlichen Alters (4, 12, 18, 25 und 36 Jahre alt) zu untersuchen und das Erosionspotenzial mit der Allgemeinen Bodenabtragsgleichung (USLE) in Beziehung zur Oberflächenbedeckung und Feinwurzeldichte zu setzen. In dieser Studie wurde die space-for-time substitution für experimentelle Feldforschung anstelle einer Langzeitbeobachtung übernommen. Räumliche Heterogenität der Bodeneigenschaften (z. B. Textur, organischer Kohlenstoffgehalt) und Topographie (Neigungssteilheit und -länge) beeinträchtigten die Erosion bei verschiedenen Pflanzungsaltern. Um dieser Herausforderung zu begegnen, nämlich mögliche Auswirkungen von Bodeneigenschaften und Gefälle auf die Erosion zu berücksichtigen, wurde das empirische USLE-Modell in der Datenanalyse, zur Berechnung der kombinierten jährlichen Bodenbedeckung, Management und support practice factor (CP), das die Ökosystem-Erosivität darstellt, verwendet. Berechnete CP-Werte variierten mit der Wachstumsphase von Kautschuk im Bereich von 0,006-0,03. Die Oberflächenbedeckung wurde als der Haupttreiber für Änderungen des erosiven Potentials in Kautschukplantagen anerkannt. Die Kautschukplantage mittleren Alters wies aufgrund der relativ geringen Oberflächenbedeckung (40% -60%) während der Regenzeit die größte Erosion (3 Mg ha-1) auf. Dies wurde auf einen geringen Unkrautbewuchs (unter 20%) und eine geringe Bodenbedeckung durch Oberflächenstreu, verursacht durch eine hohe Zersetzungsrate, zurückgeführt. Basierend auf den Ergebnissen der ersten Studie konzentrierte sich die zweite Studie auf die Verringerung des Bodenverlusts in Kautschukplantagen, indem eine hohe Oberflächenbedeckung durch verbessertes Unkrautmanagement aufrechterhalten wurde. Unter den verschiedenen getesteten Unkrautbekämpfungsstrategien reduzierte no-weeding den Bodenverlust vor Ort auf 0,5 Mg ha-1 am effizientesten. Aufgrund der geringen Akzeptanz der Unkrautbekämpfung durch den Landwirt empfehlen wir jedoch zu Beginn der Regenzeit (einmaliges Unkrautjäten) eine Herbizidapplikation auf eine Einzeldosis zu reduzieren, um den Boden besser zu erhalten und das Überwachsen der Unterholzvegetation zu verhindern. Da das zweite Experiment nur ein Jahr dauerte, während die Kautschukplantage eine mehrjährige Pflanze mit einer kommerziellen Lebensdauer von 25 bis 40 Jahren ist, wurde in der dritten Studie das LUCIA-Modell zur Simulation der zeitlichen Dynamik der Bodenerosion in Kautschukplantagen unter verschiedenen Strategien eingesetzt. Das Erosionsmodul in LUCIA wurde erweitert, um sowohl oberflächenabfluss- als auch niederschlagsbedingte Bodenerosion zu simulieren, um den Einfluss der mehrschichtigen Struktur des Plantagenschirms besser widerzuspiegeln. Das verbesserte LUCIA-Modell stellte erfolgreich die Auswirkungen des Unkrautmanagements auf den Bodenverlust und den Oberflächenabfluss am Versuchsstandort mit einer Modellierungseffizienz (EF) von 0,5-0,96 und R2 von 0,64-0,92 dar. Die Ergebnisse der Langzeitsimulationen bestätigten, dass "einmaliges Jäten" den jährlichen Bodenverlust unter 1 Mg ha-1 kontrollierte und die Unkrautabdeckung unter 50% hielt. Daher wurde diese Unkrautbekämpfungsstrategie als umwelt- und landwirtfreundliches Management in Kautschukplantagen vorgeschlagen. Darüber hinaus wurde LUCIA auf Wassereinzugsgebietsebene angewendet, um die Auswirkung der Flächenerhaltung auf den Sedimentausstoß zu bewerten. Zur Bewertung der Auswirkungen auf die Gesamtsedimentmengen wurden zwei benachbarte Teileinzugsgebiete mit unterschiedlicher Landbedeckung ausgewählt. Für die Auswirkungen von Einzelschutz (mono-conservation; Schutz nur in Kautschukplantagen) hat eine von Wald dominierende Landnutzung (S1, Kontrolle) gedient und für die Auswirkungen von Mehrfachschutz (multi-conservation; Schutz in Mais-, Kautschuk- und Teeplantagen) eine Mosaiklandnutzung (S2). Das Modell wurde gut kalibriert und validiert basierend auf dem Peak-Flow (EF von 0,70 für die Kalibrierung und 0,83 für die Validierung) und dem Sedimentertrag (EF von 0,71 für die Kalibrierung und 0,95 für die Validierung), die an den zwei Austrittsstellen des Wassereinzugsgebiets gemessen wurden. Die Modellergebnisse zeigten, dass ein verbessertes Unkrautmanagement in Kautschukplantagen die gesamten Sedimentausbeuten um 20% reduzieren kann; während Mehrfachschutz weitgehend in der Lage war, erhöhte Sedimenterträge durch Landnutzungsänderungen auszugleichen. Zusammenfassend wurde, während der Untersuchung der Dynamik von Erosionsprozessen in Kautschukplantagen, ein physikalisch basiertes Modell (LUCIA) erweitert und angewendet, um Unkrautmanagementeffekte über einen gesamten Erntezyklus (40 Jahre) und Implikationen auf höherer Maßstabsebene (Wasserscheidensedimentmenge) zu simulieren. Einmaliges Unkrautbekämpfung pro Jahr wurde als verbessertes Management identifiziert, um die Erosion vor Ort und den Sedimentaustrag außerhalb des Wassereinzugsgebietes zu reduzieren. Um den durch die Landnutzungsänderung erhöhten Sedimentausstoß jedoch vollständig ausgleichen zu können, sollte eine Mehrfachschutzstrategie angewandt werden, die sich nicht nur auf neue Landnutzungen wie Kautschukplantagen konzentriert, sondern sich auch um traditionelle landwirtschaftliche Typen kümmert. Ein konzeptueller Rahmen wird vorgeschlagen, um die spezifischen Erosionseffekte der sub-Wassereinzugsgebiete (z. B. Sediment oder Wasserausbeute) in großen Wassereinzugsgebieten durch räumliche Kombination von prozessorientierten und datengesteuerten (z. B. statistisch und machine-learning basierten) Modellen weiter zu bewerten. Diese Studie dient auch als Fallstudie zur Untersuchung ökologischer Fragen (z. B. Erosionsprozesse, Auswirkungen von Landnutzungsänderungen) auf der Grundlage von Kurzzeitdaten und Modellierung in Abwesenheit von Langzeitbeobachtungen