Nature,extent and severity of soil erosion in upland Scotland

This paper examines the nature, extent and severity of soil erosion in upland Scotland, an area subject to land management pressures typical of temperate maritime uplands. Erosion features were classified and their area measured from aerial photographs. Some 12 per cent of the upland area sampled was subject to some form of erosion, which is very similar to the percentage for Europe as a whole. The most significant erosion category was peat erosion, with 6 per cent of the area being affected; a figure which increased to 20 per cent in one sub-region. Peat erosion varied in severity, with the most severe erosion being in areas of eastern Scotland with the greatest land management pressures. Gully erosion of slopes on mineral soils was found in almost 5 per cent of the area sampled, particularly in sub-regions with large amplitude of relief. Debris flow/cone features and screes were less extensive and largely found at higher altitudes. Footpath erosion was mapped in popular mountain areas, but overall the mean length of eroded footpaths was less than that of large gullies. There was little evidence of spatial linkages between erosion of mineral soils and land management at the scale of the survey. Separating the roles of upland management and extreme rainfall events in the inception of erosion remains a key issue in the study of accelerated erosion in temperate maritime upland areas. Some guidance for management is presented.     

Spatial and temporal variations in concentrations of three ions in solutions extracted from a woodland soil

Concentrations of Cl, Mg and K in soil solutions extracted from a gleyic brown earth under mixed oak woodland were measured at weekly intervals over a 1 year period. Spatial variability of ion concentrations was large, with coefficients of variation of 30–90% in a 0.1 ha plot. Seasonal variability in Mg and K was effectively buffered by the soil exchange complex, but Cl displayed a distinct pattern with a maximum concentration in late autumn. Flushing of Cl during soil rewetting is the most probable explanation.     

In vitro Effect of Zearalenone and α-Zearalenol on Boar Sperm Characteristics and Acrosome Reaction

This study was conducted to determine the in vitro effects of three different concentrations (125, 187.5 and 250 microM in diluted semen) of zearalenone (zen) and alpha-zearalenol (alpha-zen) on boar sperm. Semen parameters such as motility, viability and spontaneous acrosome reaction were evaluated. From the results it was shown that both zen and alpha-zen affected the sperm characteristics significantly (p < 0.05), except for alpha-zen at the low concentration which did not decrease the percentage of live reacted spermatozoa significantly. In conclusion, zen and alpha-zen are directly toxic when they affect boar semen in vitro and consequently decrease the fertilization ability of the sperm. The higher the concentration of mycotoxin tested, the greater the decline of sperm parameters noticed. The influence of mycotoxins was found to be time- and dose-dependent.     

Quantifying anthropogenic nutrient sources and loadings within a small catchment with conservation interests,eastern Scotland

This paper demonstrates the possibility of quantifying sub-catchment nutrient budgets from routinely monitored hydrological and hydrochemical data. The relative importance of a number of potential anthropogenic nutrient sources was quantified for a small catchment in Scotland. Within the catchment there are two Sites of Special Scientific Interest, including two lochs and a floodplain mire. The study was undertaken to provide information for prescribing strategies to safeguard the conservation interests of these aquatic systems. The principal source of nitrate was found to be groundwater. Phosphate and ammonium loadings were greatest in surface run-off. The evidence indicates that the greatest contributor towards these nutrient sources is agriculture. Even when conservative estimates of losses were applied, current fertilizer and animal inputs could account for present day nutrient loadings. In addition, changes in the area under arable farming and under individual crops during the past 30 years are consistent with trends in nitrate and phosphate loads. Nutrient inputs from sewage works overflows and septic tanks within the catchment were estimated to be small. Leachate from a landfill site within the catchment was also not considered to be a major source of nutrients, but a more intensive water quality monitoring programme would be needed to confirm the absence of leachate plumes. The only long-term solution to reducing nutrient loadings to the aquatic systems is a reduction in agricultural activities within the catchment and avoidance of fertilizer and slurry applications near water sources. Diversion of drainage ditch waters supplying the floodplain mire is also a possibility but the hydrological consequences of such an action could induce more severe degradation than that due to nutrient enrichment.     

The effect of different combinations of lignocaine,ketoprofen, xylazine and tolazoline on the acute cortisol response to dehorning in calves

AIMS: The aims of this study were (a) to evaluate the effect of xylazine and tolazoline, with and without lignocaine, on the cortisol response of calves following amputation dehorning and (b) to assess the effect of a non-steroidal anti-inflammatory drug (ketoprofen) and local anaesthesia on the cortisol response of calves to amputation dehorning.

METHODS: Plasma cortisol concentrations were measured in 100 dehorned or non-dehorned 3-month-old calves over an 8-h period following five different sedative/analgesic or control treatments. Sedative/analgesic treatments were: control (no anaesthesia); local anaesthesia and ketoprofen; local anaesthesia and xylazine; local anaesthesia, xylazine and tolazoline; and xylazine only. Within each sedative/analgesic treatment group, half the calves (n=10 per group) were amputation dehorned and half were not dehorned.

RESULTS: The change in plasma cortisol concentrations in calves dehorned after being given ketoprofen and local anaesthesia did not differ significantly from that of non-dehorned control calves for at least 8 h. In contrast, the cortisol response of dehorned calves not given analgesic drugs peaked 30 min after dehorning and lasted >4 h. Xylazine injected before dehorning significantly reduced but did not eliminate the peak of the cortisol response. When both xylazine and local anaesthesia were administered before dehorning the peak in the cortisol response was virtually eliminated. In the dehorned calves that received xylazine with or without local anaesthesia, cortisol concentration increased significantly 3 h after dehorning and did not return to baseline until at least 5 h later. When tolazoline was administered shortly after xylazine, it caused a marked cortisol response, higher than the response to any other treatment.

CONCLUSIONS: Combining ketoprofen and local anaesthesia minimised the cortisol response, and by inference the pain- induced distress, following amputation dehorning in calves. Xylazine reduced the initial cortisol response to dehorning but not as much as when local anaesthesia was also given. The increase in cortisol concentration from 3–8 h after dehorning in calves given xylazine alone or in combination with local anaesthesia suggests that calves experienced pain-induced distress during this time and that xylazine had no long-term analgesic effect. Tolazoline, used to reverse the sedative effects of xylazine, caused a marked cortisol response in calves via a mechanism which remains unclear.     

Effect of mitochondrial uncoupling and glycolysis inhibition on ram sperm functionality

Studies have demonstrated the importance of mitochondria to sperm functionality, as the main source of ATP for cellular homoeostasis and motility. However, the role of mitochondria on sperm metabolism is still controversial. Studies indicate that, for some species, glycolysis may be the main mechanism for sperm energy production. For ram sperm, such pathway is not clear. Thus, we evaluated ram sperm in response to mitochondrial uncoupling and glycolysis inhibition aiming to assess the importance of each pathway for sperm functionality. Statistical analysis was performed by the SAS System for Windows, using the General Linear Model Procedure. Data were tested for residue normality and variance homogeneity. A p < .05 was considered significant. Groups treated with the mitochondrial uncoupler Carbonyl cyanide 3 chlorophenylhydrazone (CCCP) showed a decrease in the percentage of cells with low mitochondrial activity and high mitochondrial membrane potential. We also observed that the highest CCCP concentration promotes a decrease in sperm susceptibility to lipid peroxidation. Regardless the lack of effect of CCCP on total motility, this substance induced significant alterations on sperm kinetics. Besides the interference of CCCP on spermatic movement patterns, it was also possible to observe such an effect in samples treated with the inhibitor of glycolysis (2‐deoxy‐d ‐glucose, DOG). Furthermore, treatment with DOG also led to a dose‐dependent increase in sperm susceptibility to lipid peroxidation. Based on our results, we suggest that the glycolysis appears to be as important as oxidative phosphorylation for ovine sperm kinetics as this mechanism is capable of maintaining full motility when most of the cells have a low mitochondrial membrane potential. Furthermore, we found that changes in the glycolytic pathway trough glycolysis inhibition are likely involved in mitochondrial dysfunction and sperm oxidative unbalance.