Temperature as an indicator of landfill behavior

The utility of landfill temperature measurements both as a means of understanding landfill behavior and the interpretation of anomalous data points is explored by demonstration in a case study application. The availability of a pathway facilitating easy intrusion of atmospheric OZ into a landfill is shown to cause aerobic conditions and spontaneous combustion, during landfill pumping experiments. The landfill temperature measurements provide an effective means of isolating the extent of the problem.     

Fractal analysis of ice crystals in frozen food

Fractal analysis of the morphology of ice crystal particles in frozen food was attempted for frozen soybean curd (tofu). From a microscopic image analysis of the ice crystal particles, it was found that the perimeter of the ice crystal particles could be recognized as a fractal. Effects of the storage time and storage temperature on the fractal dimension (d(p)) of the perimeter of the ice crystal particles were also investigated. As storage time was increased, the d(p) value tended to decrease. When the storage temperature was increased, the value of d(p) decreased more rapidly. The changes corresponded to the visual observation of the shape change for the ice crystal particles during storage reported by many researchers, suggesting that the fractal dimension d(p) could be used as a quantitative indicator reflecting the surface roughness of ice crystal particles.     

Honey as an indicator of heavy metal contamination

The potential use of honey as an indicator in mineral prospecting and environmental contamination studies has been investigated. Silver, Cd, Cu, and Pb levels are reported in honeys collected throughout the U.K. The elemental content of honeys was investigated in relation to that in the soils collected from within the foraging area. For samples collected over two seasons the following concentrations were found Ag <0.1 to 6.5 ng g^?1 (d.w.); Cd <0.3 to 300 ng g^?1; Cu 35 to 6510 ng g^?1; Pb <2 to 200 ng g^?1. Considerable spatial and seasonal fluctuations were apparent. No correlations were observed between honey and soil concentrations for either Cu or Pb. It is concluded that the low concentrations of heavy metals in honey and their inherent variability (due to differences in floral source, foraging range, entrapment of atmospheric particulates on the flower, etc.) detract from the reliable use of honey as a monitoring tool. The relative merits of honeybees, pollen and beeswax for environmental monitoring or biogeochemical prospecting studies are also briefly discussed.     

Effect of freezing and frozen storage of doughs on bread quality

The effects of freezing and storage in frozen conditions on bread quality, crumb properties, and aggregative behavior of glutenins were analyzed. The effect of different additives on bread quality was also studied. The results obtained showed that freezing and storage at -18 degrees C decreased the bread quality. Samples stored in frozen conditions supplemented with diacetyl-tartaric acid ester of monoglycerides, gluten, and guar gum produced breads of greater volume and more open crumb structure than those prepared with the base formulation (without additives). All additives analyzed increased the proof time. Crumb firmness increased with dough frozen storage and bread aging time at 4 degrees C. A decrease in the amount of glutenin subunits of high molecular mass was observed by electrophoresis analysis of the SDS-soluble proteins aggregates extracted from the frozen dough. This result suggested that the protein matrix of bread underwent depolymerization during storage in frozen conditions.     

Alpha-tocopherol oxidation in fish muscle during chilling and frozen storage

The oxidation of alpha-tocopherol (TH) in chilled and frozen fish muscle was determined using high-performance liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry. TH oxidation byproducts were identified as alpha-tocopherolquinone (TQ), 5,6-epoxy-alpha-tocopherolquinone (TQE1), and 2-3-epoxy-alpha-tocopherolquinone (TQE2). The concentration of TH decreased significantly during storage while those of TQ, TQE1, and TQE2 increased noteworthy. The relative amounts of TH and its oxidized products were significantly related with the extent of oxidation produced in postmortem fish, and the ratio TQ/TH is suggested as an index of oxidative stress in fish muscle. The effect of phenolic antioxidants supplementation on retarding TH oxidation was also studied. Data suggested that the addition of 100 ppm of caffeic acid, hydroxytyrosol, and propyl gallate could regenerate endogenous TH from its oxidized forms resulting in an antioxidant synergy consistent with the reduction of lipid oxidation observed in fish muscle supplemented with phenolic compounds.     

Biological activity as an indicator of chernozem fertility in different biocenoses

Meadow chernozemic soil was studied in an idle land-shelterbelt-cropland system. It was found that the long-term agricultural use of chernozems leads to a decrease in the total nitrogen content and to changes in the soil microbial community. The portion of phytopathogenic Fusarium, Aspergillus ustus, Penicillium daleae, and Penicillium rubrum microorganisms in the complex of soil fungi increases, and the phytosanitary state of the soil worsens. The use of biotests made it possible to estimate the role of particular microorganisms in the soil phytotoxicity.     

Soil organic matter stratification ratio as an indicator of soil quality

Soil quality is a concept based on the premise that management can deteriorate, stabilize, or improve soil ecosystem functions. It is hypothesized that the degree of stratification of soil organic C and N pools with soil depth, expressed as a ratio, could indicate soil quality or soil ecosystem functioning, because surface organic matter is essential to erosion control, water infiltration, and conservation of nutrients. Stratification ratios allow a wide diversity of soils to be compared on the same assessment scale because of an internal normalization procedure that accounts for inherent soil differences. Stratification ratios of soil organic C were 1.1, 1.2 and 1.9 under conventional tillage (CT) and 3.4, 2.0 and 2.1 under no tillage (NT) in Georgia, Texas, and Alberta/British Columbia, respectively. The difference in stratification ratio between conventional and NT within an environment was inversely proportional to the standing stock of soil organic C to a depth of 15–20 cm across environments. Greater stratification of soil C and N pools with the adoption of conservation tillage under inherently low soil organic matter conditions (i.e., warmer climatic regime or coarse-textured soil) suggests that standing stock of soil organic matter alone is a poor indication of soil quality. Stratification of biologically active soil C and N pools (i.e., soil microbial biomass and potential activity) were equally or more sensitive to tillage, cropping intensity, and soil textural variables than stratification of total C and N. High stratification ratios of soil C and N pools could be good indicators of dynamic soil quality, independent of soil type and climatic regime, because ratios >2 would be uncommon under degraded conditions.     

Surface textures of intrafault quartz grains as an indicator of fault movement

Quartz grains obtained from gouges which accompany faults are observed by means of a scanning electron microscope. It is assumed that quartz grains in the gouge are formed from the breakage of quartz in the parent rock due to fault movement, with corrosion by groundwater occuring on grain surfaces after the movement. Therefore, surface textures or morphology of the grains can become a good indicator in examining the mode of fracture at the time of faulting, or the length of time elapsed since the fault moved.     

Evaluating soil microbial biomass carbon as an indicator of long-term environmental change

The aim is to assess whether soil microbial biomass carbon (biomass C) could be used as an indicator of environmental change in natural and semi-natural ecosystems. Biomass C was measured by fumigation-extraction in soils from two sites at Rothamsted. One was a plot from the Broadbalk Wheat Experiment, given inorganic fertiliser and chalk, which has been in continuous cultivation for more than 150 yr. The other was a similar sized area, from Geescroft Wilderness, which has been left to revert to woodland since 1885, after being an arable field. Other soil properties (pH, soil organic C and exchangeable cations) were also measured to compare with biomass C. The coefficients of variation (cvs) of the properties measured were calculated for comparison, little difference was found between the cvs for biomass C from each site: cv=26% for Broadbalk and 23% for Geescroft. The cvs for the other, chemical properties, were mostly <10% for Broadbalk and generally >25% for Geescroft, as expected, given the different cultivation histories. Statistical analysis of the variation in biomass C concentration revealed that such measurements would not be valid indicators of environmental change, without processing impossibly large numbers of samples. To decrease the least significant percentage change to less than 5% after three samplings, 320 samples would have to be taken each time. This would be also be true of the other chemical properties in Geescroft Wilderness, where the measured background variation would mask any subtle environmental change. This indicates that, for some properties at least, statistically significant changes will only be detected in the longer term with regular sampling, e.g. 30-40 yr.     

Light integral as an indicator of water use in commercial greenhouse nurseries

Abstract

Irrigation strategies in pot plants of Kalanchoë blossfeldiana were studied in two commercial greenhouse nurseries by continuous weighing of plants on a high-precision balance. The objectives were to study actual irrigation strategies implemented by growers and to evaluate the method of continuous weighing as a potential tool for future irrigation management. Mean values of temperature, relative humidity, light, and weight were recorded every five minutes using data loggers. The change in weight over time was estimated and related to the calculated total canopy surface area of the studied plants. The rate of weight change was then statistically tested in relation to the recorded external factors. The factor with the strongest effect on total water-consumption rate over time was the light integral. As expected, water consumption was also affected by temperature and humidity, as well as the time of day. Although the growers indicated clear irrigation strategies, the study showed that these were not implemented in a true sense or correlated to the information available in greenhouse climate computers. The study also indicated that a high-precision weighing balance might be an important tool for future control of plant growth and plant architecture through irrigation in the pot plant industry.     

不同气体环境对冻藏牡蛎品质变化的影响

为了研究冻藏期间不同气体环境(CO2、N2和有氧环境)对冻藏牡蛎品质的影响,采用不同成分气体对牡蛎进行气调包装,在冻藏((-20±1)℃)期间,测定牡蛎品质指标.结果表明:冻藏期间气体环境是影响牡蛎蛋白质变化的一个重要因素,在隔绝O<,2>的条件下能有效地减缓蛋白质的变性及分解成氨基酸和小分子的含氮物质、pH值的变化、游离'氨基酸的牛成和分解,以及挥发性盐基氮含量的增加,从而延长贮藏期.在隔绝O2的条件下,N2包装效果最好,其次是CO2处理组.     

Hydrolase activity as an indicator of the state of microbial communities in vermicomposts

The hydrolase activity was studied using the fluorescein diacetate (FDA) hydrolysis assay in order to assess the microbial activity in composts and vermicomposts obtained with participation of Eisenia fetida andrei, Aporrectodea caliginosa, and A. rosea earthworms from cattle manure, leaves, and peat. The hydrolase activity (the Michaelis—Menten constant, K _m ) was found to be lower in the vermicomposts than in the composts and correlated with a corresponding decrease in the length of fungal hyphae. The determination of the hydrolase activity according to the reaction of FDA hydrolysis may be recommended to control the process of vermicomposting and the quality of vermicomposts. Thus, the process of vermicomposting may be characterized with the use of the functional (hydrolase activity) and structural (microbial biomass, length of fungal hyphae) approaches.     

采用压汞法研究不同冷冻羊肉冰晶结构特征

为研究不同冷冻羊肉冰晶结构特征,该文以空气冷冻和液浸冷冻2种不同冷冻方式以及冻贮3和90 d不同时间的冷冻羊肉为研究对象,采用真空冷冻干燥法将冷冻羊肉体内冰晶升华,用压汞法对冰晶升华留下的孔隙结构进行测定,并观察解冻复温后肌肉微观组织结构。研究结果表明,压汞法可有效测定冷冻羊肉冰晶升华后留下的孔隙分布特征,以此来表征冰晶结构特征。通过比较空气冷冻和液浸冷冻后冻贮不同时间羊肉的孔隙结构以及解冻复温后肌纤维组织结构变化特点,发现不同冷冻羊肉冰晶升华后孔隙分布特征存在差异,空气冷冻后冻贮3和90 d以及液浸冷冻后冻贮3和90 d的冷冻羊肉最大累计进汞量分别为2.16±0.08、2.33±0.07、1.76±0.01和2.29±0.05 mL/g,孔隙平均直径为10.09±0.30、25.73±0.91、3.21±0.46和14.45±0.64 µm,存在显著差异（P<0.05）,迂曲度分别为2.27±0.05、3.88±0.05、3.15±0.08和4.41±0.16,存在显著差异(P<0.05)。该研究结果可为压汞法在冷冻肉冰晶结构参数的测定应用中提供一定的理论依据。     

常规冷冻冻藏对猪肉保水性和组织结构的影响

调查了在生产中常规冷冻工艺条件下冻结的肉块,经-18℃冷库冻藏一定时间之后,在固定解冻条件下解冻后,肉的保水性、蛋白溶解度和组织结构的变化规律。结果表明:随着冻藏时间的延长,冷冻猪肉的保水性逐渐降低,主要表现为:解冻汁液流失率、蒸煮损失率和加压失水率等逐渐升高。肉样的蛋白溶解度逐渐降低,主要是全蛋白和肌原纤维蛋白的溶解度降低。随着冻藏时间的延长,冰晶在冻结肉样中逐渐长大,导致肌束受压聚集。这可能是肉的保水性降低的一个重要原因。冻藏1个月对于肉样的各种品质特性影响不大,2个月后指标的变化比较明显,5个月后指标的变化非常明显。     

Loss of Ca and NO3-N from terrestrial microcosms as an indicator of soil pollution

Ion separation of acid air pollutants out of snow causes sudden, deep pH-drops in lakes and running waters at an early stage of snowmelting. These pH-drops have drastic effects on fish populations and are suggested to be the main cause of Sphagnum invasion and changes in the microflora already at an early stage of acidification, i.e. when summer pH-values are about 6. These effects in turn reduce the nutrient recycling and accelerate the acidification process.     

Molecular fingerprint of soil organic matter as an indicator of pedogenesis processes in Technosols

Purpose

Technosol management is one of the greatest challenges for the future, more specifically as regards supporting and/or restoring ecosystems. The understanding of natural soil organic matter (SOM) dynamic from Technosol may give important information about soil functioning and Technosol evolution.

Materials and methods

According to this, SOM from three French old mine Technosols, (an old tin mine, a lead and zinc, and a gold one which is arsenic-rich), were studied and characterized using thermochemolysis coupled with gas chromatography and mass spectrometry (GC-MS) with tetramethyl ammonium hydroxide (TMAH) as reagent and FTIR. The characterization and quantification of some specific biomacromolecules, used as biomarkers, indicate the specific level of incorporation relative to various subgroups. Global parameters of soils (pH, total organic matter, cation exchange capacity…) were also evaluated.

Results and discussion

Results on bulk samples show that lipids are the most reactive group and therefore play the most important role in young soil pedogenesis. All of the results show that the behavior of SOM of the Technosol is similar to homolog non-anthropized soil and depends on vegetation type.

Conclusions

A slight inhibition of bacterial activity is observed which underlines a protective effect of Technosols on SOM degradation due to the low pH, the high clay content, and the presence of Al³⁺ and metal(loid)s. In fine, lipid fraction of SOM may act as a well-done fingerprint of pedogenesis processes in Technosols.

     

Characterization of color fade during frozen storage of red grapefruit juice concentrates

Color changes in red grapefruit juice concentrates during storage at -23 degrees C for 12 months were studied. Concentrate (38 degrees Brix) was packed in both plastic (16 oz) and metal (6 oz) cans. Decrease in red intensity (CIE a) in juice color and slight increases in CIE L*, b*, and hue values from analysis of reconstituted juices were the characteristic color changes in concentrate during frozen storage. With respect to fresh concentrate, juice color in stored concentrate shifted toward the direction between negative DeltaC* and positive DeltaL*, indicating the color became slightly paler. A color difference seems to exist between the two containers, especially for the magnitude of DeltaE*; color changes were more pronounced in concentrates packed in plastic. There are significant changes (P < 0.05) in major carotenoid pigments (beta-carotene and lycopene) in the concentrates. More than 20% loss of lycopene and about 7% loss of beta-carotene occurred with plastic containers after a 12-month period. Regression analysis showed that the rate of decline was about 0.291 ppm per month (r = 0.990) for lycopene compared to 0.045 ppm (r = 0.817) for beta-carotene in concentrate stored in plastic. In the metal can, the same trends were observed but pigment losses were slightly smaller than those with plastic. An estimated shelf life for lycopene was 26.1 months in the metal can compared to 18 months in plastic. Shelf life for beta-carotene was more than 39 months, more than twice that of lycopene in plastic container.     

Chlorophyll as an indicator of the upper critical tissue concentration of cadmium in plants

The upper critical concentration for Cd in wheat plants (Triticum aestivum) grown in Hoagland's solution, was found by the method of Beckett and Davis (1977) to be 44 μg g^?1 dry weight, using shoot chlorophyll levels as an indicator of plant health. Chlorophyll compared favorably with other indices of growth and may, in conditions where metal toxicity is manifest as chlorosis, be more accurate and sensitive than shoot dry weights or longest root lengths. It was not possible with the limited number of experiments conducted here to determine, with any degree of confidence, differences in the levels at which chlorophylls a and b were affected.