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141.
Herbert Inhaber 《Water, air, and soil pollution》1977,7(1):3-26
An attempt to amalgamate a wide variety of land environmental data in Canada is presented. The data are shown in the form of indices, which can be defined as the comparison of a measured quantity to a standard. The indices are divided into six parts, dealing with forestry, urban overcrowding, erosion, parkland, strip mining, and sedimentation. In addition, changes in urban land use are considered. The information is primarily quantitative rather than qualitative, and national as opposed to solely local or regional. This effort marks one of the first times the land quality of an entire nation has been evaluated. Implications for policy decisions are discussed. 相似文献
142.
The baking performance of a set of flours from 13 wheat cultivars was determined by means of two different microscale baking tests (10 g of flour each). In the micro‐rapid‐mix test the dough was mixed for a fixed time at a high speed, whereas the microbaking test used mixing to optimum dough consistency in a microfarinograph. Quality parameters such as sedimentation value, crude protein content, dough and gluten extension data, and microfarinograph data were also determined. Finally, quality‐related protein fractions (gliadins, glutenins, SDS‐soluble proteins, and glutenin macropolymer) were quantitated by extraction/HPLC methods with reversed‐phase and gel‐permeation columns. All quality parameters were correlated with the bread volumes of both baking tests. The results demonstrated that the microbaking test (adapted mixing time) was much more closely related to the quality parameters than the micro‐rapid‐mix test (fixed mixing time), which hardly showed any correlation. Among the standard quality parameters, only the crude protein content showed a medium correlation with the bread volume of the microbaking test (r = 0.71), whereas the contents of gliadins (r = 0.80), glutenins (r = 0.76), and glutenin macropolymer (r = 0.80) appeared to be suitable parameters to predict the baking performance of wheat flour. All other quality parameters were not or were only weakly correlated and unsuitable for predicting baking performance. 相似文献
143.
144.
Soil nitrogen dynamics after slurry injection in field trials: Evaluation of a soil sampling strategy 下载免费PDF全文
Matthias Westerschulte Carl‐Philipp Federolf Herbert Pralle Dieter Trautz Gabriele Broll Hans‐Werner Olfs 《植物养料与土壤学杂志》2015,178(6):923-934
Slurry injection below maize seeds is a rather new application technique developed to improve the nitrogen use efficiency of liquid organic manure. To enable the characterization of the spatial and temporal soil mineral nitrogen (SMN) dynamics after slurry injection, the present study aims to develop an appropriate soil sampling strategy. Three consecutive experiments were conducted. The first testing of the soil sampling approach was conducted in an existing field trial where the slurry was injected down to a depth of 12 cm (upper rim) below the soil surface. The soil profile (75 cm wide) centered below the maize row was sampled grid‐like to a depth of 90 cm. Around the injection zone, soil monoliths (SM) were sampled using a purpose‐built soil shovel. Below the SMs and in the interrow space (15 and 30 cm distance to the row) a standardized auger procedure was performed. The second experiment aimed at improving the sampling strategy with a focus on sample homogenization quality and necessary sample sizes per pooled sample. Furthermore, the risk of a carryover of slurry components along the soil core due to drilling an auger through a slurry band was analyzed. In the third experiment this improved sampling strategy was validated. Results from the first testing of the sampling procedure showed that the strategy is suitable, although some problems occurred (especially the high spread in values among the replications causing high coefficients of variation (CV) of mostly 40–60%). The improvement trial revealed that due to the high gradient of SMN concentration in the direct range of the injection zone an intensive homogenization of these samples is required. Suitable sample sizes (twelve auger samples and six soil monolith samples per pooled sample) have to be collected to obtain reliable SMN values. Drilling an auger through a slurry band to sample subjacent soil layers has to be avoided. Following this enhanced sampling strategy, in the final validation trial the spread in values were considerably reduced and resulted in CV values of mostly < 20%. The developed sampling strategy enables the characterization of the spatial and temporal SMN dynamics when slurry has been band‐injected below a maize row. The method can be transferred to other row crops and different slurry injection spacing. 相似文献
145.
The productivity and welfare benefits of sustained swimming in fish are well documented, but are not yet exploited in commercial
aquaculture. We report here on a study designed to test the feasibility of inducing sustained exercise in Atlantic salmon
(Salmo salar L.) using a novel lighting device that provides an apparently moving light pattern. It was found that such a device could
induce sustained swimming in Atlantic salmon held in tanks and that a centrally placed (inner ring) light system was far more
effective in this context than one in which lights were placed on the outer wall of tanks. The central configuration was associated
with enhanced rates of growth, feed conversion and reduced levels of plasma cortisol. Such developments in fish swimming technologies
may assist the sustainability of finfish aquaculture through promotion of sustained exercise leading to improved productivity
and welfare. 相似文献
146.
In Maine's hatchery production of oysters, significant mortalities at the early juvenile stage have been associated with ciliate infestations. The predominant ciliate isolated from live infested oysters was identified as Uronema marinum. Feeding experiments, designed to identify the food source of the ciliate in the oyster tank environment, determined that U. marinum is a bacteriophage and not a histophage, thereby clarifying its role in the oyster mortalities. 相似文献
147.
Membranes of muscle foods are more susceptible to oxidation than triacylglycerols. Hence, directing a lipid-soluble antioxidant into the membranes may reduce the oxidative deterioration of muscle tissue. The objective of this research was to use a model system of cod muscle and triacylglycerol to study the distribution of exogenous delta-tocopherol between the membranes and triacylglycerol fractions of muscle. When ethanol was the carrier solvent, more tocopherol was incorporated into the membranes than when oil was the carrier. Addition of tocopherol to the muscle before the triacylglycerol was added allowed more antioxidant to be incorporated into the membranes than for the case when the oil was added before the antioxidant. When the triacylglycerol was solid, the amount of tocopherol incorporated into the membranes was higher than if the triacylglycerol was liquid and the amount of tocopherol incorporated into the membranes was less dependent on the order of tocopherol and triacylglycerol addition. There was a competition between the membrane lipids and triacylglycerol for uptake of the delta-tocopherol. In some circumstances, some of the tocopherol did not enter either the membrane lipid or triacylglycerol phase. 相似文献
148.
Andreas Spornberger Leopold Leder Klemens B?ck Herbert Keppel Peter Modl 《Erwerbs-Obstbau》2011,53(1):15-22
In 2010, various thinning methods were tested in an organically managed cherry orchard at the experimental farm of the Institute in Vienna. We tested a portable thinning machine (Effleureuse) and a manual method to remove flowers, and thinning of young cherries at the stage of pea size. Between beginning of flowering and full flowering we treated twice with wettable sulphur (4 %), lime sulphur (3 %), vinasse (6 %), potassium soap (Neudosan 6 %) and copper (Cuprofor 0.5 %) as well as ATS (1.8 %) as IP-standard. Additionally to the thinning effect, the impact on fruit size, fruit quality and diseases (Monilinia ssp.) was assessed. Some treatments (Effleureuse, manual thinning of young fruits, lime sulphur, ATS) showed a strong thinning effect and an increase of fruit size. Nevertheless, yield losses due to lower number of fruits caused by thinning could only partly be replaced through higher fruit size. The Effleureuse showed a high thinning effect, because of lower costs it is more suitable for farmers than hand thinning of flowers or fruits. The treatments with lime sulphur and wettable sulphur had a reducing effect on flower infestations with Monilinia laxa. No influence on fruit diseases and internal fruit quality could be found between treatments and control. 相似文献
149.
NS Matthews SW Erickson GS Light MR Slater SM Hartsfield 《Veterinary anaesthesia and analgesia》1995,22(1):25-30
The effects of tolazoline (4.0 mg/kg iv) antagonism of detomidine (0.02 mg/kg iv) were evaluated in isoflurane-anaesthetised, ventilated ponies. Each of 6 ponies received both tolazoline and saline treatment during separate anaesthetic episodes only (no surgery was performed). Detomidine administration produced an increase in blood pressure, decrease in heart rate and decrease in PaO2 Tolazoline treatment transiently increased heart rate while blood pressure returned to baseline after both treatments. Arterial oxygenation decreased further after tolazoline treatment while oxgenation recovered towards baseline with saline treatment. No other cardiopulmonary effects were detected. Recovery from anaesthesia tended to be more rapid when detomidine was antagonized. The potential benefit of antagonizing detomidine-induced bradycardia with tolazoline, during isoflurane anaesthesia should be weighed against the potential to produce a decrease in arterial oxygenation. The mechanism for this effect is not clear. 相似文献
150.
M. A. Herbert 《Forest Ecology and Management》1990,30(1-4):247-257
This paper examines some of the relationships between site, fertilizer type and foliar nutrient levels with regard to growth responses of Eucalyptus grandis (Hill ex Maid.) in order to optimise fertilizer recommendations and characterize their effect on tree growth. Six comprehensive fertilizer trials, employing confounded factorial designs, were laid out over a number of years on six sites in Natal and Zululand, covering a wide range of environmental conditions. Experiments were assessed and compared at 4 years of age in order to control within-block variation of site factors. The major growth responses were to N and/or P, N only being suitable on sandy soils low in organic matter. Topsoils very high in mineralizable N responded to applications of P only. Sites with moderate amounts of organic matter required both N and P. Potassium generally had a depressive effect. Foliar values agreed well with responses to fertilizers, and were useful in characterizing sites and determining optimum application levels. The improvement in yield as a result of fertilization was relatively greatest on poor sites. However, there was a trend for the response in absolute terms to increase with site quality. For fertilizer recommendations to be optimized, there is a need for sites to be classified in terms of their soil water availability and the organic-matter content and texture of the topsoil. As improvements in growth increase with time, they are probably due to changes in root development and structure, rather than overall nutrient status. Thus, fertilizing must be viewed only as an integrated part of establishment practices, including the condition of nursery stock, site preparation and weeding. 相似文献