Land Degradation and Soil Conservation Measures in the Moldavian Plateau, Eastern Romania: A Case Study from the Racova Catchment

Land degradation by soil erosion, gullying and landslides and reservoir sedimentation is a major environmental threat in the Moldavian Plateau of eastern Romania. The widespread development of these processes in the last two centuries was favored mainly by traditional agriculture focused on ‘up-and-down slope’ farming on small plots. However, soil conservation measures were actively undertaken between 1970 and 1989. More recent legislation (No. 18/1991 Agricultural Real Estate Act) includes two provisions that discourage maintaining and extending soil conservation practices. Hence, the former contour farming system has been abandoned in favor of the traditional, inadequate farming methods. Thus, this paper reviews the impact of land degradation and soil conservation measures in a representative 32,908 ha catchment located in the Central Moldavian Plateau. Based on field measurements, the results show that the estimated mean long-term (1973–2017) sedimentation rate reaches 4.7 cm y−1 in the Puscasi Reservoir at the catchment outlet, resulting in an associated sediment delivery ratio of 0.28. The initial area of the Puscasi Reservoir at normal retention level has decreased by 32% and the water storage capacity has decreased by 39%. Consequently, land degradation remains a serious problem in the study area and effective soil conservation is urgently needed.

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Land degradation and soil conservation in the Barlad Plateau, Romania: a case study from Racova catchment

10.5194/egusphere-egu2020-2311 ◽

2020 ◽

Author(s):

Lilian Niacsu ◽

Ion Ionita ◽

Claudia Samoila ◽

Georgel Grigoras ◽

Ana-Maria Belebea-Apostu

Keyword(s):

Land Degradation ◽

Soil Conservation ◽

Farming System ◽

Mean Value ◽

Environmental Threat ◽

Conservation Measures ◽

The Mean ◽

Landslide Distribution ◽

Soil Conservation Measures

<p>Land degradation by soil erosion, gullying, landslides and reservoir sedimentation is a major environmental threat in the Barlad Plateau of Romania. This paper reviews both land degradation and the development of soil conservation measures in a representative 32,908 ha catchment. Previous studies focused on larger regional areas and provided insufficient detailed information about land degradation and land improvements. Results estimated the mean value of soil loses at 22.7 t ha-1 y-1 based mostly on the USLE. Gully erosion is very limited in extent (covering 3% of the catchment area), but has considerable impacts in terms of sediment production and triggering or reactivating landslides. The 1:5,000 scale landslide distribution map shows that 56% of Racova Catchment is covered by landslides, in any shape or age. Most of them are shallow seated and inactive landslides. Traditional agriculture in the Barlad Plateau focused on &#8216;up-and-down slope&#8217; farming on small plots. Soil conservation measures were actively undertaken over a 20-year period (1970-1989). However, more recent legislation (No. 18/1991 Agricultural Real Estate Act) includes two provisions that discourage maintaining and extending soil conservation practises. Hence, the former contour farming system has been abandoned in favour of the traditional, degradational farming methods. The mean annual sedimentation rate in reservoirs is moderate at 2.7 cm y-1 in the upper Racova Catchment and almost double that rate in Puscasi Reservoir at the catchment outlet. Consequently, land degradation remains a serious problem in the study area and effective soil conservation is urgently needed.</p>

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Effects of land use changes and conservation measures on land degradation under a Mediterranean climate

Solid Earth Discussions ◽

10.5194/sed-7-115-2015 ◽

2015 ◽

Vol 7 (1) ◽

pp. 115-145 ◽

Cited By ~ 4

Author(s):

Y. Mohawesh ◽

A. Taimeh ◽

F. Ziadat

Keyword(s):

Land Use ◽

Organic Carbon ◽

Soil Organic Carbon ◽

Land Degradation ◽

Soil Conservation ◽

Land Use Changes ◽

Conservation Measures ◽

Stone Walls ◽

Effects Of Land Use ◽

Soil Conservation Measures

Abstract. Land degradation resulting from improper land use and management is a major cause of declined productivity in the arid environment. The objectives of this study were to examine the effects of a sequence of land use changes, soil conservation measures, and the time since their implementation on the degradation of selected soil properties. The climate for the selected 105 km2 watershed varies from semi-arid sub-tropical to Mediterranean sub-humid. Land use changes were detected using aerial photographs acquired in 1953, 1978, and 2008. A total of 218 samples were collected from 40 sites in three different rainfall zones to represent different land use changes and different lengths of time since the construction of stone walls. Analyses of variance were used to test the differences between the sequences of land use changes (interchangeable sequences of forest, orchards, field crops, and range), the time since the implementation of soil conservation measures, and rainfall on the thickness of the A-horizon, soil organic carbon content, and texture. Soil organic carbon reacts actively with different combinations and sequences of land use changes. The time since stone walls were constructed showed significant impacts on soil organic carbon and the thickness of the surface horizon. The effects of changing the land use and whether the changes were associated with the construction of stone walls, varied according to the annual rainfall. The results help in understanding the effects of land use changes on land degradation processes and carbon sequestration potential and in formulating sound soil conservation plans.

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Fallout radionuclide-based techniques for assessing the impact of soil conservation measures on erosion control and soil quality: an overview of the main lessons learnt under an FAO/IAEA Coordinated Research Project

Journal of Environmental Radioactivity ◽

10.1016/j.jenvrad.2012.01.008 ◽

2012 ◽

Vol 107 ◽

pp. 78-85 ◽

Cited By ~ 30

Author(s):

G. Dercon ◽

L. Mabit ◽

G. Hancock ◽

M.L. Nguyen ◽

P. Dornhofer ◽

...

Keyword(s):

Soil Quality ◽

Soil Conservation ◽

Erosion Control ◽

Research Project ◽

Conservation Measures ◽

Lessons Learnt ◽

The Impact ◽

Fallout Radionuclide ◽

Soil Conservation Measures

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Hydrological Response of Precipitation and Human Activities—A Case Study in the Zuli River Basin, China

10.20944/preprints201804.0122.v1 ◽

2018 ◽

Author(s):

Chenlu Huang ◽

Qinke Yang ◽

Weidong Huang ◽

Junlong Zhang ◽

Yuru Li

Keyword(s):

River Basin ◽

Human Activities ◽

Soil Conservation ◽

Test Methods ◽

Sediment Discharge ◽

Contribution Rate ◽

Conservation Measures ◽

Reduction Effect ◽

The Impact ◽

Soil Conservation Measures

Precipitation and human activities are two essential forcing dynamics that influence hydrological processes. To investigate those impacts, the Zuli River Basin (ZRB, a typical tributary basin of the Yellow River in China) was chosen to identify the impact of precipitation and human activities on runoff and sediment discharge. A double mass curve (DMC) analysis and the test methods, including accumulated variance analysis, sequential cluster, Lee-Heghnian, and moving t-test methods was utilized to determine the abrupt change point based on data from 1956 to 2015. Correlation formulas and multiple regression methods were used to calculate the runoff and sediment discharge reduction effects of soil conservation measures and to estimate the contribution rate of precipitation and soil conservation measures to runoff and sediment discharge. Our results show that the runoff reduction effect of soil conservation measures (45%) is greater than the sediment discharge reduction effect (32%). Soil conservation measures were the main factor controlling the 74.5% and 75.0% decrease in runoff and sediment discharge, respectively. Additionally, the contribution rate of vegetation measures was higher than that of engineering measures. This study provides scientific strategies for water resource management and soil conservation planning at catchment scale to face future hydrological variability.

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The Effect of Soil Conservation Measures on Runoff, Soil Erosion, TN, and TP Losses Based on Experimental Runoff Plots in Northern China

Water ◽

10.3390/w13172334 ◽

2021 ◽

Vol 13 (17) ◽

pp. 2334

Author(s):

Haiyan Fang

Keyword(s):

Soil Erosion ◽

Soil Conservation ◽

Soil Loss ◽

Northern China ◽

Nutrient Losses ◽

Study Region ◽

Conservation Measures ◽

The Impact ◽

Soil Conservation Measures ◽

Runoff Plots

Total nitrogen (TN) and total phosphorous (TP) are the main pollutants affecting the water quality of the Miyun Reservoir, Beijing. However, few studies have been conducted on their responses to implemented soil conservation measures at a slope scale in northern China. To explore the impact of soil conservation measures on TN and TP losses, field monitored data from 18 runoff plots under natural rainfalls were used to analyze the changing characteristics of runoff, soil loss, and nutrient losses during 2014–2019. The results indicated that runoff, soil erosion, as well a TN and TP losses from the plots varied significantly, depending on land use and soil conservation measures. Bare plots suffered the highest soil, TN, and TP losses, followed by cultivated plots without soil conservation measures, cultivated plots with contour tillage, and other plots. Event-averaged runoff and soil loss rates ranged from 0 to 7.9 mm and from 0 to 444.4 t km−2 yr−1, and event-averaged TN and TP losses from cultivated plots were the highest, with values of 39.8 and 3.0 kg km−2, respectively. Bare and cultivated plots were the main sediment and nutrient sources. Among the cultivated plots, the terraced plot had the lowest soil and nutrient losses. The vegetated plots had insignificantly lower soil and nutrient losses. Most TN and TP were lost in particulate status from the plots, especially from the plots with soil conservation measures. Soil conservation measures can effectively prevent TN and TP losses. To guarantee water resource use, contour tillage is preferred for the bare and cultivated lands in the study region.

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Hydrological Response to Precipitation and Human Activities—A Case Study in the Zuli River Basin, China

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15122780 ◽

2018 ◽

Vol 15 (12) ◽

pp. 2780 ◽

Cited By ~ 1

Author(s):

Chenlu Huang ◽

Qinke Yang ◽

Weidong Huang ◽

Junlong Zhang ◽

Yuru Li ◽

...

Keyword(s):

River Basin ◽

Human Activities ◽

Soil Conservation ◽

Test Methods ◽

Sediment Discharge ◽

Contribution Rate ◽

Conservation Measures ◽

Reduction Effect ◽

The Impact ◽

Soil Conservation Measures

Precipitation and human activities are two essential forcing dynamics that influence hydrological processes. Previous research has paid more attention to either climate and streamflow or vegetation cover and streamflow, but rarely do studies focus on the impact of climate and human activities on streamflow and sediment. To investigate those impacts, the Zuli River Basin (ZRB), a typical tributary basin of the Yellow River in China, was chosen to identify the impact of precipitation and human activities on runoff and sediment discharge. A double mass curve (DMC) analysis and test methods, including accumulated variance analysis, sequential cluster, Lee-Heghnian, and moving t-test methods, were utilized to determine the abrupt change points based on data from 1956 to 2015. Correlation formulas and multiple regression methods were used to calculate the runoff and sediment discharge reduction effects of soil conservation measures and to estimate the contribution rate of precipitation and soil conservation measures to runoff and sediment discharge. Our results show that the runoff reduction effect of soil conservation measures (45%) is greater than the sediment discharge reduction effect (32%). Soil conservation measures were the main factor controlling the 74.5% and 75.0% decrease in runoff and sediment discharge, respectively. Additionally, the contribution rate of vegetation measures was higher than that of engineering measures. This study provides scientific strategies for water resource management and soil conservation planning at catchment scale to face future hydrological variability.

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Water-Saving Soil Conservation Measures Should Be Used in Northern China: Evidence from Runoff Plot Data

Water ◽

10.3390/w13060853 ◽

2021 ◽

Vol 13 (6) ◽

pp. 853

Author(s):

Haiyan Fang

Keyword(s):

Soil Conservation ◽

Soil Loss ◽

Water Saving ◽

Rainfall Amount ◽

Vegetation Coverage ◽

Fish Scale ◽

Study Region ◽

Conservation Measures ◽

The Impact ◽

Soil Conservation Measures

Most of the current studies on soil conservation measures mainly focus on their soil control effect, neglecting their impact on water quantity. In the present study, the latest seven years (2014–2020) of monitored data from 22 runoff plots in the upstream catchment of the Miyun Reservoir, Beijing were used to evaluate the effects of slope, rainfall, and soil conservation measures on soil and water loss, and some implications were given in this water-scarce region. Excluding the impact of soil conservation measures, soil loss increased with the slope gradient and slope length. Runoff and soil loss were greatly affected by the rainfall amount and maximum 30-min rainfall intensity on the bare and cultivated slopes, or by rainfall amount and rainfall duration on almost all of the plots with soil conservation measures. The results indicated that the bare soil suffered the most severe soil loss, with a mean annual soil loss rate (SLR) of 4325 t km−2 year−1, followed by the cultivated lands without any measure, with an annual SLR of above 3205 t km−2 year−1. Contour tillage cannot effectively control soil loss on steep slopes. The vegetation measures and terrace, level bench, and fish scale pits, as well as their combinations, can decrease runoff by above 86% and decrease soil loss by 95%, respectively. Water-saving measures should be implemented in the study region. The measures, such as vegetation coverage, terracing, contour tillage, etc., should be carefully implemented on slopes. Bare and cultivated lands should further be implemented with soil conservation measures in this and similar regions in the world.

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