Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year per...Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive (Olea europaea cv. Picual) trees under: 1) non-tillage with barley strips of 4 m width (BS); 2) non-tillage with native vegetation strips of 4 m width (NVS); and 3) non-tillage without plant strips (NT). The erosion plots, located in Lanjaron (Granada, south-eastern Spain), on a 30% slope, were 192 m2 in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance probes were installed in the middle of plant strips and beneath the olive tree at five soil depths (10, 20, 30, 50, and 100 cm). The highest erosion and runoff rates were measured under NT, with a mean of 17.3 Mg ha-1 year-1 and 140.0 mm year-1, respectively, over the entire study period. The BS and NVS with respect to the NT reduced erosion by 71% and 59% and runoff by 95% and 94%, respectively. In general, greater available soil water content was found under BS than NVS and NT, especially beneath the olive tree canopies. These results supported the recommendation of non-tillage with barley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.展开更多
The effect of soil and water conservation (SWC) practices on controlling surface runoff and soil loss was studied in drought prone banana growing areas of Uganda, during the two major rainy seasons of 2014. The stud...The effect of soil and water conservation (SWC) practices on controlling surface runoff and soil loss was studied in drought prone banana growing areas of Uganda, during the two major rainy seasons of 2014. The study was conducted at two sites-- Ntungamo (Southwest) and Sembabule (Central), with comparable slopes of about 13%-25%. The treatments included mulch, manure, manure + mulch and a control with no conservation. Results indicated that conservation practices of mulch and manure + mulch significantly reduced surface runoff and soil loss by about 72%-85%, when compared to farmers' up-and-down cultivation practice (control). It was also observed that significantly greater amounts of soil loss occurred from manure and control plots than the ones with mulch. Thus, the combination of manure and mulch is recommended for uptake by crop farmers in the study areas, if they are to overcome drought stress and adapt to changes in climate. More research is needed to quantify nutrient losses resulting from runoff under the different SWC techniques. Modeling such effects is essential in assessing the impacts of SWC practices on soil and crop productivity.展开更多
基金Project supported by the European Union (No.EU QLK5-CT2002-01841)
文摘Sloping and mountainous olive production systems are widespread, occupying large parts of the Mediterranean landscape prone to water erosion. Soil erosion, runoff, and soil water content patterns over a three-year period were monitored in erosion plots on a mountainside with rainfed olive (Olea europaea cv. Picual) trees under: 1) non-tillage with barley strips of 4 m width (BS); 2) non-tillage with native vegetation strips of 4 m width (NVS); and 3) non-tillage without plant strips (NT). The erosion plots, located in Lanjaron (Granada, south-eastern Spain), on a 30% slope, were 192 m2 in area. For assessing soil water dynamics in real-time and near-continuous soil water content measurements, multisensor capacitance probes were installed in the middle of plant strips and beneath the olive tree at five soil depths (10, 20, 30, 50, and 100 cm). The highest erosion and runoff rates were measured under NT, with a mean of 17.3 Mg ha-1 year-1 and 140.0 mm year-1, respectively, over the entire study period. The BS and NVS with respect to the NT reduced erosion by 71% and 59% and runoff by 95% and 94%, respectively. In general, greater available soil water content was found under BS than NVS and NT, especially beneath the olive tree canopies. These results supported the recommendation of non-tillage with barley strips in order to reduce erosion and to preserve soil water for trees in traditional mountainous olive-producing areas, where orchards cover vast tracts of land.
文摘The effect of soil and water conservation (SWC) practices on controlling surface runoff and soil loss was studied in drought prone banana growing areas of Uganda, during the two major rainy seasons of 2014. The study was conducted at two sites-- Ntungamo (Southwest) and Sembabule (Central), with comparable slopes of about 13%-25%. The treatments included mulch, manure, manure + mulch and a control with no conservation. Results indicated that conservation practices of mulch and manure + mulch significantly reduced surface runoff and soil loss by about 72%-85%, when compared to farmers' up-and-down cultivation practice (control). It was also observed that significantly greater amounts of soil loss occurred from manure and control plots than the ones with mulch. Thus, the combination of manure and mulch is recommended for uptake by crop farmers in the study areas, if they are to overcome drought stress and adapt to changes in climate. More research is needed to quantify nutrient losses resulting from runoff under the different SWC techniques. Modeling such effects is essential in assessing the impacts of SWC practices on soil and crop productivity.