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1.
At this time the European Union regulations require that the heterotrophic plate counts (HPC) of mineral waters be assessed at two recovery temperatures: 22 degrees C for 72 h and 37 degrees C for 24 h. This procedure is time consuming and expensive. Development of new rapid methods for microbiological assessment of the microbial flora in the bottled water is an industry-driven need.The objectives of this work were to develop a method for the HPC that utilises only one recovery temperature and one incubation period and evaluate the use of, the LIVE/DEAD(R) BacLight Bacterial Viability Kit, 5-cyano-2,3-ditotyl tetrazolium chloride (CTC) and impedance methods to enumerate viable bacteria in bottled mineral water.Results showed that incubation at 30 degrees C could be used instead of incubation at 22 degrees C and 37 degrees C. Good correlation exists between counts at 30 degrees C and counts at 22 degrees C (r>0.90) and all the pathogens important in mineral water analyses grow similarly at 30 degrees C and 37 degrees C during 24 h.It was demonstrated that impedance methods might be useful to the mineral water industry as a rapid indicator of microbiological quality of the water.Results obtained with BacLight and CTC were similar to those obtained with plate counts.  相似文献   

2.
矿泉水是地下水从含水层中经长期与岩石相互作用形成、富含有益于人体的丰富矿物质和微量元素的一类顶级饮用地下水资源.在水资源污染严重而且生态环境不断恶化的今天,基于新的科技认知手段重新认识矿泉水的生态和健康效应,具有重要意义.黑龙江省五大连池风景区拥有着五大连池旅游疗养业赖以生存和发展的优质矿泉水资源,并且被应用于医疗和保健方面已有百余年历史,但是面临着资源量减少、环境污染等问题的威胁.本文主要针对五大连池矿泉水的形成过程、分布规律、水化学和微生物特征及其健康效应等进行综合评述,侧重其微生物特征的研究进展,提出了未来五大连池矿泉的研究展望.为了更好地保护和利用五大连池矿泉水,建议五大连池周边农场发展绿色生态农业,减少化肥的施用;在开发旅游和疗养资源的同时,要严格建立污染风险的评估和管控体系,减少“新型”环境污染物对地质生态环境的可能污染.  相似文献   

3.
Water-deficit stress is a major constraint on plant productivity and consequently, is a major focus of much research. Stress is often imposed on plants in these experiments by withholding water from the artificial potting media on which the plants are grown. No attention has been given, however, to the possibility of differences in the dynamics of stress imposition between that resulting from dehydration of the artificial rooting media and that of drying of mineral soil. The objective of this research was to compare transpiration rates during drying of a mineral soil and of an artificial potting mixture for three test species: Arabidopsis thaliana, maize (Zea mays), and soybean (Glycine max). These results showed major differences in transpiration response between the two soil media. Drying of mineral soil confirmed previous observations that no decrease in transpiration rates occurred until 0.27–0.34 of the extractable water remained in the soil. Thereafter, there was essentially a linear decrease in transpiration with further soil drying. In contrast, transpiration rates of plants grown on the potting mixture began to decrease when about 0.6–0.7 of the extractable water still remained in the soil. Consequently, plants grown on the potting mixture as compared to the mineral soil were exposed to stress very early in the drying cycle and the stress was much more prolonged over a wide range of soil moistures. Caution is warranted in extrapolating to natural, mineral soils the results obtained from plants subjected to water-deficits using artificial potting mixtures.  相似文献   

4.
It is well known that the intake of sulfate-containing natural mineral waters leads to contraction of the gallbladder, probably induced by the release of cholecystokinin (CCK). As early as 1959, there were some hints in the literature of circadian variations in gallbladder response; to find out whether this applies with sulfate as a stimulus, a pretest for basic information about gallbladder reaction to sulfate-containing mineral water was carried out on 19 healthy volunteers. On this basis, 15 healthy subjects of both sexes were then studied. After 6h of fasting, 500 mL of a sulfate-containing mineral water (2,800 mg SO4(2-)/L) were ingested within 5 min. The size of the gallbladder was registered ultrasonographically before and 15, 30, 60, and 120 min after drinking. The experiments were carried out seven times at different hours of the day for each volunteer. After the intake of the mineral water, the mean gallbladder size decreased significantly, followed by an increase after 60 min (P < .001). Significant circadian spontaneous variation in gallbladder size was detected (acrophase around 09:00; amplitude was 30.0% of daily average, P < .001). The contraction induced by the sulfate-containing water was most marked in the early morning hours and minimal around mid-day; the amplitude of this variation accounting for 29.0% of the daily average (P < .01). In contrast, the postdrinking relaxation was maximal around 18:00 and minimal around 9:00 (amplitude 38.5%. P < .001). These results show that the basal size of the gallbladder and its reaction to stimuli show a marked circadian variation: Whereas contractibility is maximal in the morning, dilatation is stronger in the afternoon.  相似文献   

5.
In two trials, pigs were given lucerne juice (LJ) as the only protein supplement from 20–90 kg liveweight. The effects of reducing the mineral supplementation of the meal given with LJ and of increasing water intake were studied.In Trial 1, a total of 45 pigs were given either control diets with 7% white-fish meal to 54 kg liveweight and 3.5% thereafter, or diets in which the fish meal provided by the control diets was replaced with LJ. The meal mixture given with LJ was either supplemented or unsupplemented with limestone flour, dicalcium phosphate and salt. In the former case, as in previous studies, the Ca, P and Na content of LJ was not taken into account in formulating the meal mixture; in the latter treatment, taking these into account eliminated the need for supplements.In Trial 2, 18 pigs received LJ at a similar level to that given in Trial 1, together with a meal mixture without the mineral supplements. The water intake of half the pigs was restricted to 2.5 l/kg meal, including the water in LJ. The remaining pigs had, in addition, a supply of water ad libitum.The pigs given LJ in Trial 1 had much lower growth rates and feed: gain ratios than the controls given white-fish meal. A significant, but relatively small, improvement in performance was achieved by giving LJ with the unsupplemented meal rather than with meal supplemented with minerals. In Trial 2, supplying additional water ad libitum significantly increased feed intake. There was a tendency for this to increase daily gain, although the difference was not significant.Despite the improvements due to adjustments of mineral and water intake, the performance of the pigs given LJ as the only protein supplement was unsatisfactory. This may be due to the very high level of potassium in LJ. This cannot be taken into account in formulating a practical basal meal mixture.  相似文献   

6.
Recent studies have demonstrated the potential application of computed tomography (CT) in research into bone density. Clinical studies of bone density using CT commonly employ a dipotassium phosphate phantom to calibrate measurements of mineral density. Designed for in vivo studies, the use of this phantom requires that bones be scanned while immersed in and permeated by fluids or soft tissues similar to water in X-ray attenuation coefficient. However, this condition may not always be met in anthropological applications, which often involve rare and fragile specimens. This study compares mineral density values calculated for a sample of bones scanned—at the same sites—in air and in water. The results indicate that, when scanned in air, the mineral density of trabecular bone is dramatically underestimated, while that of cortical bone is slightly overestimated. We present a linear regression equation to correct this error but recommend that, when possible, researchers calculate their own regressions based on their specific scanning conditions. Am J Phys Anthropol 103:557–560, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

7.
The aims of this study were to evaluate whether balneotherapy with mineral sulphate-bicarbonate-calcium water could determine substantial symptomatic improvement, and to detect any changes in the quality of life (QoL) of patients with symptomatic knee osteoarthritis (OA). This was a prospective randomized, single blind controlled trial. Sixty outpatients with primary bilateral knee OA, according to ACR criteria, were included in the study and randomized to one of two groups: group I (30 patients) was treated with a daily sulphate-bicarbonate-calcium mineral water bath; group II (30 patients), the control group, continued their regular outpatient care routine. At baseline, after 15 days and after 12 weeks, patients were evaluated by Visual Analogue Scale (VAS) for spontaneous pain, Lequesne and Womac Index for gonarthrosis, SF-36, Arthritis Impact Measurement Scale (AIMS) and symptomatic drugs consumption. We observed a significant improvement of all parameters at the end of the cycle of balneotherapy which persisted throughout the follow-up period, whereas in the control group no significant differences were noted. This symptomatic effect was confirmed by the significant reduction of symptomatic drugs consumption. The differences between the two groups were significant for all considered parameters already from the 15th day and persisted during follow-up. Tolerability of balneotherapy seemed to be good, with light and transitory side effects. Our results confirm that the beneficial effects of balneotherapy in patients with knee OA last over time, with positive effects on the painful symptomatology, a significant improvement on functional capacities and QoL. Balneotherapy can represent a useful backup to pharmacological treatment of knee OA or a valid alternative for patients who do not tolerate pharmacological treatments.  相似文献   

8.
土壤铁矿物形态转化影响有机碳固定研究进展   总被引:1,自引:0,他引:1  
宋旭昕  刘同旭 《生态学报》2021,41(20):7928-7938
铁是地壳中丰度第四高的元素,其可通过多种方式影响土壤有机碳累积,尤其铁氧化物与土壤有机碳相互作用形成的稳定有机-矿物复合物,被认为是土壤可溶性有机碳长期固定的关键地球化学机制。促进土壤固定有机碳不仅可以提高土壤质量和肥力,还是应对全球气候变化的主要策略之一。然而,铁活跃的氧化还原反应和多样化的赋存形态,使其转化过程对土壤有机碳累积和稳定性的影响结果受到诸多生物和非生物因素调控。从不同角度,结合多学科的研究成果,综述了近年来国内外关于铁矿物形态转化影响土壤有机碳固定的相关研究,包括铁矿物形态转化过程、土壤有机碳固定机制、铁矿物形态转化影响土壤有机碳固定的机制及其主要影响因素(各种环境条件、自身的铁矿物性质、碳源质量等方面),强调铁在土壤有机碳固定过程中的重要作用。对铁固定土壤有机碳的相关研究提出了建议,为今后研究提供相关参考。  相似文献   

9.
Many animals in the tropics of Africa, Asia and South America regularly visit so-called salt or mineral licks to consume clay or drink clay-saturated water. Whether this behavior is used to supplement diets with locally limited nutrients or to buffer the effects of toxic secondary plant compounds remains unclear. In the Amazonian rainforest, pregnant and lactating bats are frequently observed and captured at mineral licks. We measured the nitrogen isotope ratio in wing tissue of omnivorous short-tailed fruit bats, Carollia perspicillata, and in an obligate fruit-eating bat, Artibeus obscurus, captured at mineral licks and at control sites in the rainforest. Carollia perspicillata with a plant-dominated diet were more often captured at mineral licks than individuals with an insect-dominated diet, although insects were more mineral depleted than fruits. In contrast, nitrogen isotope ratios of A. obscurus did not differ between individuals captured at mineral lick versus control sites. We conclude that pregnant and lactating fruit-eating bats do not visit mineral licks principally for minerals, but instead to buffer the effects of secondary plant compounds that they ingest in large quantities during periods of high energy demand. These findings have potential implications for the role of mineral licks for mammals in general, including humans.  相似文献   

10.
矿质养分输入对森林生物固氮的影响   总被引:1,自引:0,他引:1  
郑棉海  陈浩  朱晓敏  毛庆功  莫江明 《生态学报》2015,35(24):7941-7954
生物固氮是森林生态系统重要的氮素来源,并且在全球氮循环中占有重要的地位。近代以来,因人类活动加剧而导致氮沉降的增加以及其它矿质养分元素(如磷、钼、铁等)输入的改变已成为影响森林生态系统生物固氮的重要因素之一,并引起了学术界的普遍关注。综述了国内外关于森林生物固氮对矿质养分输入的响应及机理。主要内容包括:(1)森林生物固氮的概念及主要的测定方法;(2)矿质养分输入对森林生物固氮的影响。整体上讲,氮素输入抑制了森林生物固氮,磷和其他营养元素输入则表现为促进作用。氮和磷、磷和微量元素同时添加均提高了森林的固氮量;(3)矿质养分改变森林生物固氮的机理。包括生物作用机制(如改变地表层固氮菌的数量或群落丰度、改变结瘤植物的根瘤生物量和附生植物的丰度或盖度)和环境作用机制(如引起土壤酸化、改变碳源物质的含量);(4)探讨了矿质养分输入对森林生物固氮影响研究中所存在的问题,并对未来该领域的研究提出建议。  相似文献   

11.
We conducted three exploratory experiments of factorial design on the effects of mineral turbidity in 18 large (7 000 1) fiberglass tanks containing plankton communities derived from Lake Texoma (Oklahoma-Texas), a large reservoir often subject to turbid inflows. Replicate plankton communities developed for 30–45 d in response to 4–9 treatments of planktivorous fish, dead fish, nutrient additions and artificial removal of zooplankton with plankton netting (or combinations of these manipulations). In one experiment we then added three concentrations of kaolin and in the other two experiments we added bentonite or powdered silica to the replicate tank communities. We measured the responses of the diverse plankton communities to the addition of mineral turbidity for an additional period of 30–45 d.Effects of introduced minerals (quality or concentration effects) and food web treatments after mineral addition (fish, nutrients, etc.) were determined by analysis of covariance after observations were adjusted for the value of each response variable at the time of mineral addition. Covariance analysis resulted in a statistical model explaining > 80% of the variance for most response variables. The values of response variables at the time of mineral addition were often the most important source of variation, suggesting the importance of biotic community resiliency to the effects of mineral turbidity. There were few effects of mineral particles on physical or chemical (temperature, conductivity, oxygen, pH), nutrient (nitrate, phosphate, alkalinity) or biotic (algal or zooplankton populations) components of the tank communities. Mineral effects were found for several measures of water clarity (Secchi depth, turbidity, and the concentration of small sestonic particles).  相似文献   

12.
Pepper seed quality is sensitive to variations in climatic conditions during seed development, which might be associated with accumulation, distribution and leakage of mineral elements from the seeds. This was examined in hybrid seeds of sweet pepper (Capsicum annuum L. cv.‘Hazera’ 1195) in two experiments during two growing seasons. The mean daily temperature (day/night) and daily total radiation receipt during seed development were 27.9/23.2°C and 8.63 kW m?2 in the summer and 18.3/ 14.9°C and 3.18 kW m?2 in the winter, respectively. Seeds developed in the summer had lower percentage of seedling emergence and leaked a larger portion (45%) of their K content into the water medium than in winter‐developed seeds. Summer seeds accumulated more K and Cl, but less P, Mg, Ca and the weight ratio of linoleic acid to oleic acid was lower than in the winter seeds. The season did not significantly affect N, S and total fatty acids. The most abundant element on the seed coat surface was K in the summer and Ca in the winter seeds. The cotyledon and endosperm of the summer seeds contained relatively higher ratios of K and Ca and lower ratios of P and Mg than the winter seeds. Transportation of mineral nutrients appeared to be involved in the effect of heat and moisture stresses on emergence quality of the pepper seeds.  相似文献   

13.
Recent surveys of peatland initiation that occurred over the past 10,000 years in northeastern Alberta have revealed that most peatlands initiated by paludification, or swamping of upland soils. Peatland ecologists have long known the importance of the paludification process, but it has not been transferred to peatland restoration methodologies. We initiated this study to determine if wetland structure and function could be re-established on two well sites established with mineral fill within a peatland complex. At two well sites near Peace River, AB, the mineral material was lowered to near the water level of the surrounding peatland. We placed 288 plots of 2 m × 2 m in size using a series of fertilizer, water level, cultivation, and amendment treatments and then introduced a suite of wetland plants. Four questions are addressed: - (1) Will locally available peatland vascular plant species establish on these wet, compacted, mineral soils? If so: (2) are species responses affected by these treatments? (3) are plants that we did not introduce in the planting regime (weeds) a concern? and (4) will the surrounding bog water chemistry have an effect on water in contact with mineral soils? Results after two growing seasons are - (1) Carex aquatilis and Salix lutea have all successfully established at both well sites; (2) C. aquatilis plants (ramets) have increased to an average of 58.5 per plot, up from the 16 original genets planted; (3) the plant responses to amendments are not significantly different from the control plots; (4) weed abundance is significantly different among some amendment types; and (5) pad ditch water chemistry is affected by the surrounding bog waters.  相似文献   

14.
J. A. M. Janssen 《Oecologia》1993,95(3):401-409
The effects of organic nitrogen, nitrate, phosphorus, potassium and water content of leaves of intact maize plants, grown in a gravel culture system, on the fitness of the African armyworm, Spodoptera exempta (Walker)(Lepidoptera: Noctuidae) were studied. Organic nitrogen concentrations ranged from 1.3% to 3.7% over four treatments differing only in nitrate supply to the plants. Water content and other mineral levels were all positively correlated with the organic nitrogen level. Feeding damage by the caterpillars was most severe on the lowest nitrate treatments, where it could be least well compensated for by new leaf growth. Larval and pupal fitness variables were not affected by treatment, except for larval development on the lowest nitrate treatment which was delayed by just 1 day. The large compensatory capacity of the larvae was underlined by a similar mineral composition of the pupae in all treatments. Adult fitness variables hardly differed between the upper three nitrate treatments, but revealed a trend over all treatments: the higher the organic nitrogen content of the leaves, the shorter the pre-oviposition period and the higher the fecundity. This trend, however, might have been due to differences in available food quantity rather than in food quality. It is concluded that fitness of the African armyworm is only slightly affected over a wide range of nitrogen concentrations in its food. Though effects might be larger under field conditions, the large differences in outbreak development between years seem not to be attributable to observed differences in nitrogen levels in host plants between years in primary outbreak areas. Other environmental factors appear to be of greater importance.  相似文献   

15.
Matrix vesicles (MVs) are involved in de novo mineral formation by nearly all vertebrate tissues. The driving force for MV mineralization is a nucleational core composed of three principal constituents: (i) amorphous calcium phosphate (ACP), complexed in part with phosphatidylserine (PS) to form (ii) calcium-phosphate-lipid complexes (CPLX), and (iii) annexin A5 (AnxA5), the principal lipid-dependent Ca(2+)-binding protein in MVs. We describe methods for reconstituting the nucleational core using a biomimetic approach and for analyzing the kinetics of its induction of mineral formation. The method is based on light scattering by the nascent crystallites at 340 nm and monitors mineral formation at regular intervals without disturbing the system using an automated plate reader. It yields precise replicate values that typically agree within less than 5%. As with MVs, mineral formation by the synthetic complex follows a sigmoidal pattern; following a quiescent induction period, rapid formation ensues for a limited time, followed by a distinct decline in rate that continues to slow, ultimately reaching a maximal asymptotic value. Key to quantization of mineral formation is the use of first-derivative analysis, which defines the induction time, the rate and the amount of initial mineral formation. Furthermore, using a five-parameter logistic curve-fitting algorithm, the maximal amount of mineral formation can be predicted accurately. Using these methods, we document the dramatic finding that AnxA5 synergistically activates PS-CPLX, transforming it from a very weak nucleator of mineral formation to a potent one. The methods presented should enable systematic study of the effects of numerous other factors thought to contribute to mineral formation.  相似文献   

16.
The overall aim of this study was to evaluate the benefit of mixing two large volume wastes, namely mineral processing waste and source-segregated green waste compost, on the growth performance of plants targeted towards high (horticulture/agriculture) and low (amenity/restoration) value markets. The secondary aims were to evaluate the influence of mineral waste type on plant growth performance and to undertake a simple economic analysis of the use of mineral-compost mixtures in land restoration. Our results showed that in comparison to organic wastes, mineral wastes contained a low available nutrient content which reduces compost quality. This is supported by growth trials with tomato, wheat and grass which showed that, irrespective of mineral source, plants performed poorly in compost blended with mineral waste in comparison to those grown in green waste or peat-based compost alone. In terms of consumer confidence, unlike other wastes (e.g. biosolids and construction/demolition waste) the mineral quarry wastes can be expected to be free of potentially toxic elements, however, the production costs of compost-mineral waste mixtures and subsequent transport costs may limit its widespread use. In addition, handling of the material can be difficult under wet conditions and effective blending may require the purchase of specialist equipment. From our results, we conclude that mineral fines may prove useful for low quality, low value landscaping activities close to the source of production but are unsuited to high value markets.  相似文献   

17.
Abstract: Earlier investigations on laboratory and pilot plant scale have shown the resort to microorganisms to be a practicable approach to the problem of purifying mineral dressing plant reject waters from residual flotation reagents and/or metal ions. In spite of the proven effectiveness of this method, one major drawback, namely the pathogenicity of some microorganisms, has so far hampered its application on a commercial scale. A research programme, aimed at developing a microbial reject water purification technique utilizing non-pathogenic strains was thus drawn up and is currently being implemented. Strains such as Bacillus subtilis, Saccharomyces cerevisiiae, Bifidobacterium bifidum, Lactobacillus acidophilus and Acinetobacter calcoaceticus , which are not harmful to human health, some of them being commonly found in the human intestine, have been successfully tested for removing alkylsulphates, alkylamines and fany acids from solutions simulating flotation plant tailings waters. Removals as high as 90% in less than 48 h can be easily achieved with no nutrient requirements, since in most cases the flotation reagent residue to be removed is metabolized by the microorganisms themselves.  相似文献   

18.
Aquaporins are the intrinsic membrane proteins functioning as water channel to transport water and/or mineral nutrients across the biological membrane systems. In this research, we aimed to clarify if the selected mineral water can affect aquaporin functions in vitro and the assumption of the mineral water can modify aquaporin expression and activate natural killer cell activity in human body. First, we expressed six human and eight plant aquaporin genes in oocytes and compared the effect of different kinds of natural mineral water on aquaporin activity. The oocyte assay data show that Hita tenryosui water could promote water permeability of almost all human and plant aquaporins in varying degrees, and freeze-dry and organic solvent extraction could reduce AQP2 activity but pH change and boiling could not. Second, each volunteer in two groups (10 in one group) received an oral Hita tenryosui or tap water load of 1000 ml/day for total four weeks. We found that these two kinds of water did not directly affect the relative expression levels of AQP1 and AQP9 in the blood cells, but intriguingly, the natural killer cell activities of the volunteers drinking Hita tenryosui water were significantly improved, suggesting that Hita tenryosui water has obvious health function, which opens a new and interesting field of investigation related to the link between mineral water consumption and human health and the therapies for some chronic diseases.  相似文献   

19.
基于GIS的山西省矿产资源规划环境影响评价   总被引:2,自引:0,他引:2  
刘伟  杜培军  李永峰 《生态学报》2014,34(10):2775-2786
基于目前我国矿产资源规划编制过程中的环境评价,提出了一种基于GIS(Geographic Information System)技术,实现矿产资源规划环境影响定量评价方法。在对规划区环境现状进行大尺度综合评价的基础上,利用GIS的空间分析功能,有针对性的实现规划区敏感环境保护目标的筛选、环境影响范围的确定和矿产资源开发对环境保护目标影响程度的定量表达。结合山西省矿产资源规划方案,根据山西省各区域资源开发对敏感保护目标的影响特征,在定量计算各区域环境现状综合评价分级的基础上,分别对其生态环境、水环境、地质环境等方面的影响进行评价和预测,结果显示:山西省矿产资源规划空间布局总体合理,不会对敏感环境保护目标造成严重破坏,但部分矿产资源开采区距离保护目标较近,需要在矿产资源规划实施中加以保护。提出的评价方法较好地兼顾矿产资源开发与区域环境保护,可以有效地提高矿产资源规划环境评价结果的准确性和科学性;该方法可以综合地、定量地评价矿产资源规划对不同环境保护目标的影响程度和范围,为矿产资源规划方案的修订提供有价值的参考。  相似文献   

20.
A physico-chemical process has been developed to transform and enhance lignocellulosic waste in liquid humic extracts: humic-like substances (HLS). The aim of this study was to determine the effects of HLS on plant physiology in order to consider their agricultural use as organic fertilizers. The effects of HLS were evaluated on maize seed germination, and their impact on growth, development and mineral nutrition was studied on maize plants cultivated under hydroponic conditions. The experimental results showed that HLS do not increase the percentage and rate of germination but enhance the root elongation of seeds thus treated. Positive effects were also observed on the whole plant growth as well as on root, shoot and leaf biomass. These effects can be related to the high water and mineral consumption of plants undergoing this treatment. The high water efficiency indicated that such plants produce more biomass than non-treated plants for the same consumption of the nutrient solution. Furthermore, the use of HLS induced a flowering precocity and modified root development suggesting a possible interaction of HLS with developmental processes. Considering the beneficial effect of HLS on different stages of plant growth, their use may present various scientific and economic advantages. The physico-chemical transformation of sawdust is an interesting way of enhancing organic waste materials.  相似文献   

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