The role of land management practices in soil erosion hazard in eucalypt stands in north-central Portugal following forest wildfires

The ongoing intensification of grazing as well as the replacement of traditional land management systems in the Maghreb has brought to the forefront the fundamental role of land-use in determining soil erosion hazard. This paper reports on erosion rates and soil hydrological characteristics of a variety of land uses in Morocco and Tunisia. The results were obtained through rainfall simulation experiments carried out in the field using a portable simulator, following the design of CERDÀ et al. (1997). Traditional land management systems - typically involving a combination of agriculture, animal husbandry and forestry - produced the least amounts of overland flow and the lowest soil erosion rates. Over-exploitation of these systems apparently has only minor hydrological and erosional impacts. Heavily grazed, degraded "maquis" shrublands, on the other hand, produced considerable amounts of overland flow. At the plot scale of the rainfall simulation experiments (0.24 m2), the corresponding sediment loads are rather insignificant. Nevertheless, slopes where "maquis" shrublands (which generally have very compacted soils) occur upslope from more erodible soils may present a major erosion hazard.

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Analysis of Farmers’ Perception on the Impact of Land Degradation Hazard on Agricultural Land Productivity in Jeldu District in West Shewa Zone, Oromia, Ethiopia

Energy and Environment Research ◽

10.5539/eer.v8n2p20 ◽

2018 ◽

Vol 8 (2) ◽

pp. 20

Author(s):

Tesfaye Samuel Saguye

Keyword(s):

Soil Erosion ◽

Land Management ◽

Land Degradation ◽

Management Practices ◽

Local Community ◽

Agricultural Land ◽

Land Productivity ◽

Community Knowledge ◽

Process Indicators ◽

The Impact

Land degradation is increasing in severity and extent in many parts of the world. Success in arresting land degradation entails an improved understanding of its causes, process, indicators and impacts. Various scientific methodologies have been employed to assess land degradation globally. However, the use of local community knowledge in elucidating the causes, process, indicators and effects of land degradation has seen little application by scientists and policy makers. Land degradation may be a physical process, but its underlying causes are firmly rooted in the socio-economic, political and cultural environment in which land users operate. Analyzing the root causes and effects of land degradation from local community knowledge, perception and adapting strategies perspective will provide information that is essential for designing and promoting sustainable land management practices. The main objective of this study was to analyze the perceptions of farmers’ on the impact of land degradation hazard on agricultural land productivity decline associated with soil erosion and fertility loss. The study used a multistage sampling procedure to select sample respondent households. The sample size of the study was 120 household heads and 226 farm plots managed by these farmers. The primary data of the study were collected by using semi-structured Interview, focus group discussions and field observation. Both descriptive statistics and econometric techniques were used for data analysis. Descriptive results show that 57percent of the respondents were perceived the severity and its consequence on agricultural land productivity. The following indicators of soil erosion and fertility loss were generally perceived and observed by farmers’ in the study area: gullies formations, soil accumulation around clumps of vegetation, soil deposits on gentle slopes, exposed roots, muddy water, sedimentation in streams and rivers, change in vegetation species, increased runoff, and reduced rooting depth. The direct human activities which were perceived to be causing land degradation in the study area include: deforestation and clearing of vegetation, overgrazing, steep slope cultivation and continuous cropping. The farmers’ possibility of perceiving the impact of land degradation hazard on agricultural land productivity was primarily determined by institutional, psychological, demographic and by bio-physical factors. Farmers who perceive their land as deteriorating and producing less than desired, tend to adopt improved land management practices. On the other hand, farmers who perceive their land to be fertile tend to have low adoption of conservation practices. In order to overcome this land degradation and its consequent effects, the study recommended a need for the government to enforce effective policies to control and prevent land degradation and these policies should be community inclusive /participatory founded up on indigenous and age-honored knowledge and tradition of farmers' natural resource management as well as introduced scientific practices.

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Adoption of Multiple Sustainable Land Management Practices among Irrigator Rural Farm Households of Ethiopia

10.22541/au.161366032.26549459/v1 ◽

2021 ◽

Author(s):

Rahel Deribe Bekele ◽

Alisher Mirzabaev ◽

Dawit Mekonnen

Keyword(s):

Water Management ◽

Land Management ◽

Irrigation Water ◽

Management Practices ◽

Soil Health ◽

Sustainable Land Management ◽

Irrigation Water Management ◽

Irrigation Technology ◽

Irrigation Technologies

Using a household and plot-level survey conducted in 2016/17 in ten districts of Ethiopia, this study explores whether there is a difference in farmers’ adoption of sustainable land management (SLM) practices between their rainfed and irrigated plots. The paper also investigates the varying influence of different types of irrigation water management systems and associated irrigation technologies on the adoption of SLM practices in irrigated plots. Our findings show only a small difference in the average number of SLM practices between rainfed and irrigated plots, even though significant differences are observed between many of the practices applied individually among these plots. The econometric estimation shows that the role of the combined effect of irrigation water management system and irrigation technology on adoption of SLM practices is quite varied and very significant. The evidence highlights that farmers adopt more SLM practices in their plots with pump irrigation compared to those plots where gravity irrigation is applied. This finding implies that pump irrigation systems enhance complementarities with SLM practices. Furthermore, the results indicate that the type of irrigation water management and the technology applied could play an important role in restoring degraded lands and maintaining soil fertility, even when farmers’ adoption of irrigation were not explicitly triggered by concerns for soil health.

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Development of a Coupled Water Quality Model

Transactions of the ASABE ◽

10.13031/trans.12002 ◽

2017 ◽

Vol 60 (4) ◽

pp. 1153-1170 ◽

Cited By ~ 1

Author(s):

Lili Wang ◽

Dennis C. Flanagan ◽

Keith A. Cherkauer

Keyword(s):

Water Quality ◽

Time Series ◽

Soil Erosion ◽

Total Phosphorus ◽

Land Management ◽

Management Practices ◽

Nitrate Nitrogen ◽

Storm Events ◽

Nutrient Losses ◽

Soluble Phosphorus

Abstract. . Nonpoint-source (NPS) pollutants, especially from agriculture, continue to be a primary source of waterquality degradation problems. Effective land management decisions at the field scale must be made to minimize nutrient losses that could pollute streams. Existing NPS models often cannot directly estimate the impacts of different land management practices or determine the effectiveness of combined best management practices (BMPs) in a distributed way at the farm scale. In many cases, they rely on application of the Universal Soil Loss Equation (USLE) or its improved versions, which represent fields in a lumped fashion and use empirical rather than process-based modeling methodologies. In this study, a coupled Water Erosion Prediction Project and Water Quality (WEPP-WQ) model was completed, updated, improved, and evaluated for simulation of hydrology, soil erosion, and water quality. The WEPP model is a well-established process-based model that simulates runoff and erosion processes from a hillslope. The water quality components are based on those of the Soil and Water Assessment Tool (SWAT). A single overland flow element (OFE) on a hillslope is used to represent a single soil and land use management. The WEPP-WQ model was tested by comparing simulated values from the coupled model with observed nutrient and sediment concentrations in surface runoff following storm events at experimental sites near Waterloo in northeastern Indiana and at the Throckmorton Purdue Agricultural Center in west central Indiana. Time series evaluation of the WEPP-WQ model was performed with observed nutrient and sediment losses from an experimental plot near Tifton, Georgia. The model performed quite well in simulating nutrient losses for single storm events, with R2 greater than 0.8, Nash-Sutcliffe efficiency (NSE) greater than 0.65, and percent bias (PBIAS) less than 31% for runoff, sediment, nitrate nitrogen, total nitrogen, soluble phosphorus, and total phosphorus losses. In predicting time series nutrient loss, the WEPP-WQ model simulated daily nitrate nitrogen losses adequately, with the ratio of the root mean square error to the standard deviation of measured data (RSR) less than 0.7, NSE greater than 0.55, and PBIAS within the range of ±40%. Comparisons between simulated soluble phosphorus, total phosphorus, and literature results were performed due to the absence of an available observational dataset. The WEPP-WQ model with a single OFE in this study provides a basic but important step for the development of WEPP-WQ models with multiple OFEs that can evaluate the effectiveness of BMPs Keywords: Modeling, Nitrogen, Phosphorus, Soil erosion, Water quality, WEPP.

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