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1.
Abstract

Two lysimeter experiments were conducted on annual leaching losses of calcium (Ca), potassium (K), sodium (Na), chloride (Cl), sulphate‐sulphur (SO4‐S), and magnesium (Mg) (one experiment only) from a sandy soil in central England during 1988–1995 to provide information on typical nutrient losses under arable agriculture below 1.2 m (Experiment 1) or 1.5 m (Experiment 2). Total annual losses, in the absence of manure additions, were highly dependent on the amount of drainage; flow‐weighted average concentrations were similar between years within experiments. Concentrations, averaged over the duration of the experiments were 74 and 78 mg L‐1 Ca, 17 and 27 mg L‐1 Na, 11 and 8 mg L‐1 K, 74 and 77 mg L‐1 Cl, and 57 and 38 mg L‐1 SO4‐S for the two experiments respectively; Mg concentration was 17 mg L‐1. Applications of chicken litter were made to some of the lysimeters in the last three years, and all nutrients showed increased leaching as a result. Application rates akin to disposal (rather than for crop fertilization) produced the largest losses. Following a total application of 125 t ha‐1 over three years, average concentrations in water draining below 1.5 m in the final year were 57 and 277 mg L‐1 Ca, 22 and 75 mg L‐1 Cl, 7 and 14 mg L‐1 K, 22 and 57 mg L‐1 Na, 27, and 125 mg L‐1 SO4‐S for the untreated and manured soils, respectively.  相似文献   

2.
The purpose of this paper is to provide a sediment-flux quantification in a vineyard context (Vosne-Romanée, Burgundy, France) where medium-term soil budget and sustainability are controlled by complex interactions between natural processes (rill erosion) and anthropogenic processes (earth supply transferred back into the rills by the winegrowers).  相似文献   

3.
Land preparation for mechanisation in vineyards of the Anoia–Alt Penedès region, NE Spain, has required major soil movements, which has enormous environmental implications not only due to changes in the landscape morphology but also due to soil degradation. The resulting cultivated soils are very poor in organic matter and highly susceptible to erosion, which reduces the possibilities of water intake as most of the rain is lost as runoff. In order to improve soil conditions, the application of organic wastes has been generalised in the area, not only before plantation but also every 3–4 years at rates of 30–50 Mg ha− 1 mixed in the upper 30 cm.These organic materials are important sources of nutrients (N and P) and other elements, which could reduce further fertilisation cost. However, due to the high susceptibility to sealing of these soils, erosion rates are relatively high, so a higher nutrient concentration on the soil surface increases non-point pollution sources due to runoff.The aim of this study is to analyse the influence of applied composted cattle manure on infiltration, runoff and soil losses and on nutrients transported by runoff in vineyards of the Alt Penedès–Anoia region, NE Spain. In the two plots selected for the analysis, composted cattle manure had been applied in alternate rows 1 year previous to the study. In each plot soil surface samples (0–25 cm) were taken and compared to those of plots without manure application. The study was carried out at laboratory scale using simulated rainfall. Infiltration rates were calculated from the difference between rainfall intensity and runoff rates, and the sediment and total nitrogen and phosphorus were measured for each simulation. In addition, the influence of compost was investigated in the field under natural rainfall conditions by analysing the nutrient concentration in runoff samples collected in the field (in the same plots) after seven rainfall events, which amount different total precipitation and had different erosive character.Compost application increases infiltration rates by up to 26% and also increases the time when runoff starts. Sediment concentration in runoff was lower in treated (13.4 on average mg L− 1) than in untreated soils (ranging from 16.8 to 23.4 mg L− 1). However, the higher nutrient concentration in soils produces a higher mobilisation of N (7–17 mg L− 1 in untreated soils and 20–26 mg L− 1 in treated soils) and P (6–7 mg L− 1 in untreated soils and 13–19 mg L− 1 in treated soils). A major part of the P mobilised was attached to soil particles (about 90% on average) and only 10% was dissolved. Under natural conditions, higher nutrient concentrations were always recorded in treated vs. untreated soils in both plots, and the total amount of N and P mobilised by runoff was higher in treated soils, although without significant differences. Nutrient concentrations in runoff depend on rainfall erosivity but the average value in treated soils was twice that in untreated soils for both plots.  相似文献   

4.
《CATENA》2007,69(2-3):177-185
Land preparation for mechanisation in vineyards of the Anoia–Alt Penedès region, NE Spain, has required major soil movements, which has enormous environmental implications not only due to changes in the landscape morphology but also due to soil degradation. The resulting cultivated soils are very poor in organic matter and highly susceptible to erosion, which reduces the possibilities of water intake as most of the rain is lost as runoff. In order to improve soil conditions, the application of organic wastes has been generalised in the area, not only before plantation but also every 3–4 years at rates of 30–50 Mg ha 1 mixed in the upper 30 cm.These organic materials are important sources of nutrients (N and P) and other elements, which could reduce further fertilisation cost. However, due to the high susceptibility to sealing of these soils, erosion rates are relatively high, so a higher nutrient concentration on the soil surface increases non-point pollution sources due to runoff.The aim of this study is to analyse the influence of applied composted cattle manure on infiltration, runoff and soil losses and on nutrients transported by runoff in vineyards of the Alt Penedès–Anoia region, NE Spain. In the two plots selected for the analysis, composted cattle manure had been applied in alternate rows 1 year previous to the study. In each plot soil surface samples (0–25 cm) were taken and compared to those of plots without manure application. The study was carried out at laboratory scale using simulated rainfall. Infiltration rates were calculated from the difference between rainfall intensity and runoff rates, and the sediment and total nitrogen and phosphorus were measured for each simulation. In addition, the influence of compost was investigated in the field under natural rainfall conditions by analysing the nutrient concentration in runoff samples collected in the field (in the same plots) after seven rainfall events, which amount different total precipitation and had different erosive character.Compost application increases infiltration rates by up to 26% and also increases the time when runoff starts. Sediment concentration in runoff was lower in treated (13.4 on average mg L 1) than in untreated soils (ranging from 16.8 to 23.4 mg L 1). However, the higher nutrient concentration in soils produces a higher mobilisation of N (7–17 mg L 1 in untreated soils and 20–26 mg L 1 in treated soils) and P (6–7 mg L 1 in untreated soils and 13–19 mg L 1 in treated soils). A major part of the P mobilised was attached to soil particles (about 90% on average) and only 10% was dissolved. Under natural conditions, higher nutrient concentrations were always recorded in treated vs. untreated soils in both plots, and the total amount of N and P mobilised by runoff was higher in treated soils, although without significant differences. Nutrient concentrations in runoff depend on rainfall erosivity but the average value in treated soils was twice that in untreated soils for both plots.  相似文献   

5.
A. Usn  M. C. Ramos 《CATENA》2001,43(4):679
The most common index to predict rainfall erosivity is based on the kinetic energy (KE) and the maximum intensity in a 30-min period. However, rainfalls recorded in the Mediterranean climate are, in most cases, the short duration (<30 min) and the high intensity. The goal of this work was to improve rainfall erosivity indices for the Mediterranean conditions from experimental interrill soil losses measured in natural conditions in 1-m2 plots. The plots were located in three vineyard fields, whose soils are classified as Typic Calcixerept, Typic Xerofluvent and Typic Xerorthent, and ploughed at the same time as the vineyards. Soil losses and runoff were collected after each rainfall event during 1 year and rainfall data were obtained from bucket gauges installed at the same places. Mean intensity of the storms was less than 10 mm h−1, but maximum intensities in short periods were as high as 103 mm h−1. Kinetic energy was calculated using different expressions proposed in the literature and improved with our data obtained with a disdrometer type Joss Waldvogel. Soil losses were related to kinetic energy and to different combinations of kinetic energy and maximum intensity for different time intervals. The best correlation was that obtained between soil losses and the product of kinetic energy by Sempere Torres and the maximum intensity in 5-min intervals (I5), which explained more than 80% of the variability. When a surface crust was formed quickly there was no significant relation between soil loss and rainfall parameters.  相似文献   

6.
A computerized empirical model for estimating the crop yield losses caused by machinery-induced soil compaction and the value of various countermeasures is presented, along with some examples of estimations made with it. The model is based mainly on results of Swedish field trials, and predicts the effects of compaction in a tillage system that includes mouldboard ploughing. It is designed for use at farm level and predicts four categories of effects: (1) Effects of recompaction after ploughing. The calculations are based on the wheel track distribution in the field and the relationship between “degree of compactness” of the plough layer and crop yield. (2) Effects of plough layer compaction persisting after ploughing. Crop yield losses are estimated from traffic intensity in Mgkm ha−1 (Mgkm = the product of the weight of a machine and the distance driven), soil moisture content, tyre inflation pressure and clay content. (3) Effects of subsoil compaction. The calculations are similar to those presented under point (2), but only vehicles with high axle load are considered. These effects are the most persistent. (4) Effects of traffic in ley crops. The estimations are based on wheel track distribution, soil moisture content and several other factors.  相似文献   

7.
8.
Abstract. Runoff and soil loss were measured using simulated rainfall at nine shrubland sites on gypsiferous soils in the Ebro Valley. The sites represented diverse physiographical situations, including three soil types, three slopes and different percentages of rock outcrop and vegetation cover. Soil type, slope and vegetation cover significantly affected runoff and soil losses. An average of 40% of the simulated rainfall (48 mm/h) appeared as runoff and amounts were positively correlated with soil losses. The greatest runoff and soil losses were from plots with the steepest slopes. Rock outcrops decreased soil losses.  相似文献   

9.
Soil inputs produced by rainfall waters washed off through a Ribeiro vineyard (Galicia, northwestern Spain) confirmed that levels recovered are <5% of the added fungicides. Laboratory studies showed that some fungicides were degraded in the ODS cartridge used for the collection of fungicides washed off by rainfall. Procymidone wash-off data obtained in the vineyard can be explained by a first-order rate mass transfer model. A procedure for the collection of wash-off waters based on octadecylsilane solid phase extraction, followed by an analytical method of reverse-phase liquid chromatography with diode array detection is presented for the evaluation of fungicide inputs into soils after being washed off vineyards by rainfalls. Quality parameters of the analytical method yielded good precision (RSD < 10%) and low detection limits (ranging between 1 and 21 microg/L).  相似文献   

10.
Grass buffer strips limit the transfer of pesticides from cultivated fields to rivers. These solutions are generally efficient at reducing polluted surface flows, mainly by infiltration of the soil, raising the question of the fate of the infiltrated pollutants. An environmental evaluation was conducted on the efficiency of a grass strip receiving diuron-contaminated water from an uphill vineyard in France. During two runoff events, the following measurements were taken: surface inflow and outflow with Venturi flumes, vertical percolated flow below the root layer (0-50 cm), and variations in water and solute content of the root layer. One runoff event occurred under natural rainfall conditions, while the other runoff event was artificially provoked with water doped by diuron and bromide. For the natural runoff event, representative of medium intensity events, 94% of the diuron was retained in the root layer, whereas 2% left the grass strip by surface runoff and 4% left the grass strip in the water percolating under the root zone. For the artificial event, representative of intense runoff events, more than half of the incoming diuron was retained by the grass strip, whereas 24% and 18% of it were transferred by surface runoff and percolation, respectively. These results showed that the capacity of the root layer to retain diuron was highly significant despite a large percolation flux. However, for large runoff events, surface and subsurface losses can still be considerable, up to 40% of the pesticide load entering the strip.  相似文献   

11.
Trichloroethylene (TCE), as one of the most common chlorinated organic compounds in soils and aquifers at many industrial sites, is carcinogenic and often recalcitrant in environment. TCE degradation in artificially contaminated soil samples was conducted using Fenton-like processes, i.e., by addition of excess hydrogen peroxide (H2O2 ). H 2 O 2 could directly oxidize TCE without addition of ferrous iron in contaminated soil. Under the optimal condition (H2O2 concentration of 300 mg kg 1 , pH at 5.0, and reaction time of 30 min), the removal efficiency of TCE in the soil was up to 92.3%. When the initial TCE concentration increased from 30 to 480 mg kg 1 in soil, the TCE removal rates varied from 89.2% to 86.6%; while the residual TCE in soil ranged from 2.28 to 47.57 mg kg 1 . Results from successive oxidations showed that the TCE removal rate with the TCE concentration of 180 mg kg 1 increased slightly from 91.6% to 96.2% as the number of successive oxidation cycle increased from one to four. Therefore, increasing the frequency of H2O2 oxidation was perhaps a feasible way to increase TCE removal rate for TCE-contaminated soil.  相似文献   

12.
The implementation of soil and water conservation structures in semiarid areas, usually poses a difficult design problem. This is, in large part, due to the high variability of rainfall and the huge potential impact of extreme hydrologic events on structures and on the landscape in general. Magnitudes of runoff and soil loss or sedimentation rates in those environments are better not assessed by conventional modelling techniques, which tend to average out event magnitude and recurrence variability in time and space. A probability-based approach is proposed here to analyse and predict rainfall erosion losses. The maximum annual storm and its associated erosivity is used as a core element in the assessment of annual interrill and rill erosion rates. Frequency and cumulative soil loss distributions are obtained by combining verified annual and maximum daily rainfall frequency distributions with a proposed erosion algorithm. This stochastic representation of erosion permits to evaluate soil losses for the maximum annual storm, as well as annual erosion rates as a function of recurrence interval. The proposed method was verified with a short series of measured soil loss data in Cape Verde. The physical basis underlying the prediction algorithm and method in general, could be sustained by experimental data and field survey evidence. The method seems applicable to arid and semiarid ecosystems with a high seasonal concentration of precipitation and with rainfall limited to only a few major storm events.  相似文献   

13.
《CATENA》2004,57(1):1-14
The generation of surface runoff and transport of sediment were studied on unpaved forest roads in the Iberian Range (Spain). To this end, a mobile rainfall simulator was used so that information could be compared. Twenty-eight rainfall simulations were carried out on the cutslope (12), sidecast fill (6) and roadbed (10). Under low soil moisture conditions, cutslopes had runoff coefficients of 58%, and overland flow was generated in 3 min. On the sidecast fill and the roadbed, the runoff coefficients were 34% and 46%, respectively. The part of the road that showed the greatest erosion was the cutslope (161 g m−2), where mass wasting and freeze–thaw processes supply loose material to be transported by overland flow. The cutslope soil loss rates exceed those from the sidecast fill and the roadbed by 16 and 11 times, respectively. In these tests, the maximum sediment concentration was recorded in the first few minutes. The concentration reduces with time as a consequence of the exhaustion of loose surface material. Correlation coefficients and regression analysis showed that the gradient, plant cover density and stone cover of the cutslopes, fill areas and roadbeds had statistically significant effects on runoff and erosion. A comparison of these data with others obtained on different land-uses allowed us to conclude that some parts of forest roads have similar hydromorphological behaviour to abandoned fields in mountainous areas and to cereal fields.  相似文献   

14.
Li  Ying  Li  Baolin  Lei  Qiuliang  Yan  Tiezhu  Du  Xinzhong  Luo  Jiafa  Lindsey  Stuart  Di  Hongjie  Liu  Hongbin 《Journal of Soils and Sediments》2022,22(9):2354-2364
Journal of Soils and Sediments - Runoff and soil erosion reflect the interactions of soil properties and rainfall. However, few researchers have investigated the forms of nitrogen lost, the first...  相似文献   

15.
Dissolved organic carbon (DOC) and nitrogen (DON) have been hypothesized to play a central role in nutrient cycling in agricultural soils. The aim of this study was to investigate the annual dynamics of DOC and DON in a Greek vineyard soil and to assess the potential role of DON in supplying N to the vines. Our results indicated that significant quantities of DOC and DON existed in soil throughout the year and that peaks in concentration appeared to correlate with discrete agronomic events (e.g. onset of irrigation and plowing). Both field and laboratory experiments showed that free amino acids were rapidly mineralized in soil and that consequently free amino acids represented only a small proportion of the soil's total soluble N. Due to rapid nitrification the soil solution N was dominated by NO3. Based upon the calculation of a plant-soil N budget and previous studies on N uptake in Vitis vinifera L., it is likely that DON uptake does not directly supply significant amounts of N to the plant. As the soil was not N limited we hypothesize that amino acids are used by the microbial community more as a source of C rather than a source of N. While we conclude that DON constitutes a significant N pool in vineyard soils further work is required to chemically characterize its constituent units and their relative bioavailability so that their overall role in N cycling can be determined.  相似文献   

16.
Soil physical properties influence vineyard behaviour; therefore, the knowledge of their spatial variability is essential for making vineyard management decisions. Little work has been conducted at high spatial resolution on soil properties at depths lower than 0.30 m which is of special relevance to perennial crops. The objectives of this work were to (i) analyse the spatial and vertical variability of soil depth, particle size fractions and water‐holding capacity (WHC) by geostatistical techniques; (ii) study the causes of the variability, with additional information from classical soil sampling; and (iii) assess the significance of WHC through its relationship with vine vigour. The work was carried out in a vineyard of eight hectares within the D.O.Ca. Rioja (northern Spain). Soil variability was determined via grid sampling at three depth ranges (0–0.30, 0.30–0.60 and 0.60–0.90 m). A conventional soil survey provided additional information on soil variability. Clay, sand and silt fractions, soil organic matter content, WHC and pruning weight were determined. Most soil properties had strong or moderate spatial dependence, with the exceptions of sand at 0.30–0.60 m and silt in the topsoil. Topography and soil erosion caused the spatial variability of soil depth and contributed to the spatial distribution of particle size fractions in the topsoil, while the heterogeneity of parent material influenced the spatial pattern of soil properties at 0.60–0.90 m. The WHC and soil depth spatial distributions related well to that of vine vigour, demonstrating the importance of knowing the spatial variability of these soil properties.  相似文献   

17.
ABSTRACT

Nutrient leaching from clay soils can show extreme temporal and spatial variation. Using an optical sensor (hourly data storage), a Swedish field with vermiculite clay was monitored for water flow (Q expressed in mm), turbidity values (TURB), and nitrate-nitrogen concentrations (CNO3N, mg L-1) in four hydrological years representing different cropping/soil management regimes. Mean TURB-Q slope (1300) decreased in the order: ploughed soil > winter wheat > unfertilized fallow > winter wheat after drainage system renovation + structure-liming of topsoil and backfill, estimated in the initial phase from 16 selected autumn events. A similar ranking was found for variability in turbidity relative to that in discharge (CV T/CV Q) in the entire autumn. Mean CNO3N-Q slope (=2) was significantly lower under fallow than in the three cropping systems (7-32), confirming results from adjacent experimental plots. A spring-period had no snow cover or intensive rain, but in situ monitoring revealed that nutrient leaching was still substantial. Particulate- and dissolved reactive phosphorus, and nitrate-nitrogen leaching was estimated reasonably well (less than 8% difference) based on in situ high-frequency resolution measurements, compared with laboratory analysis of weekly composite samples. Accurate assessment of C-Q relationships in agricultural drainage water across temporal and spatial scales is therefore important.  相似文献   

18.
The purpose of this study was to analyze the influence of wind erosion on the productivity of citric crops over gypsiric Fluvisols in Gador area (Almeria, SE Spain) by blowing air through a wind tunnel. Wind erosion varies considerably depending on time since the last tillage. This is because a physical crust forms after tilling which protects the soil from wind. Crust formation in the study area is strongly favored by dew, which causes them to form in around a week. The repeated measurements ANOVA, as a nonparametric alternative to the ANOVA, using the Geiiser method and the Friedman test shows significant differences (P ≤ 0.05) in the fractions of very fine sand and coarse silt, which confirmed that very fine sand and coarse silt are the fractions most susceptible to loss from wind. The same statistical analysis for fertility showed smaller differences in organic carbon and K2O content, while N and P2O5 increased. Nutrients lost from wind imply an additional fertilization cost for a crop to be economically feasible. The cost of this restoration of nutrients lost from the soil because of wind erosion was based on experimental data taken in crusted soil and immediately after tilling. Losses in organic matter (O.M.), N, P2O5 and K2O were estimated based on the cost of fertilizers most commonly used in the area.  相似文献   

19.
20.
Between the elevations of 1000 and 2000 m in the mid‐hills of Nepal, over 12 million people subsist on land‐holdings of less than 0·5 ha. These farmers have limited access to commercial inputs such as fertilisers and are reliant on organic manures for soil fertility maintenance. Participatory research was conducted with farmers on bari land (upper slope rain‐fed crop terraces) in the hill community of Landruk (bench terraces 0–5° slope, 3000–3500 mm annual rainfall, which aimed to develop soil and water management interventions that controlled erosion without resulting in high leaching, and so were effective in minimising total nutrient losses. Interventions tested were the control of water movement through diversion of run‐on and planting fodder grasses on terrace risers on bench terraces. The interventions were effective in reducing soil loss from the bari land in comparison with existing farmer practices, but no effect was observed on nutrient losses in solution form through runoff and leaching. Losses of NO3‐N in leachate ranged from 17·3 to 99·7 kg ha−1 yr−1, but only 0·7 to 5·6 kg ha−1 yr−1 in runoff. The overall nutrient balance suggests that the system is not sustainable. Fertility is heavily dependent on livestock inputs and if the current trends of declining livestock numbers due to labour constraints continue, further losses in productivity can be expected. However, farmers are interested in interventions that tie ecosystem services with productivity enhancement and farmers' priorities should be used as entry points for promoting interventions that are system compatible and harness niche opportunities. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

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