首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
顾丹  王颖  赵华 《生物技术》2007,17(5):83-86
目的:采用堆肥技术处理城市污泥以实现城市污泥的农用资源化进行了研究。方法:重点分析了污泥与粉煤灰混合厌氧堆肥过程中重金属铜稳定化的效果,分别按照污泥与粉煤灰质量比为1∶1;3∶1和4∶1进行混合,在常温下进行厌氧堆肥17d。结果:实验表明污泥与粉煤灰3∶1混合堆肥过程中铜的稳定化效果最佳。结论:堆肥过程有利于污泥的资源化利用。  相似文献   

2.
The investigation deals with ways of increasing the number of species by means of artificial introduction of algae. After inoculation, the authors recorded 212 species and forms: 128 in spring, 165 in summer, 119 in autumn and 61 in winter. The maximal cell number of phytoplankton occurs in summer, the minimal in winter. The active role of algae in the sewage purification is shown.  相似文献   

3.
盐城滩涂沙棘叶营养成分年动态研究   总被引:3,自引:0,他引:3  
以2003年4月~10月在盐城滩涂区沙棘(H ipp ophae rham noid es subsp.sinensis)林地采集的沙棘叶为材料,采用高效液相色谱法(HPLC)测定氨基酸、维生素和黄酮类物质的含量,并分别用ICP-M S和ICP-AES方法测定有毒重金属Cd、Pb和其它微量元素的含量.结果表明:(1)C a、K、M g、Zn和F e的含量分别在4.860~12.194g/kg、6.361~11.001 g/kg、2.302~3.833 g/kg、25.5~31.0 m g/kg和211~598 m g/kg干重之间;Pb和Cd的含量分别在0.83~2.13 m g/kg和0.29~0.94 m g/kg干重之间;(2)18种氨基酸总含量在13.33~18.41 g/100g干重之间,其中天冬氨酸、色氨酸和谷氨酸含量较高.(3)维生素C、维生素E、芦丁、槲皮素、异鼠李(黄)素含量分别在124.3~190.5 m g/100 g、4.16~7.97 m g/100 g、141.23~352.67 m g/100 g、6.71~32.62 m g/100 g和1.72~3.79 m g/100 g干重之间;(4)粗蛋白、粗脂肪、粗纤维和粗灰分含量分别在15.16~22.42 g/100 g、4.36~11.94g/100 g、12.34~17.38 g/100 g和4.90~9.81 g/100 g干重之间.沙棘叶含有丰富的微量元素、氨基酸、维生素和黄酮类物质等营养成分,具有较高的营养价值,可作为动物饲养和其它工业利用的原料.  相似文献   

4.
The present study was conducted to assess the suitability of sewage sludge amendment (SSA) in soil for Beta vulgaris var. saccharifera (sugar beet) by evaluating the heavy metal accumulation and physiological responses of plants grown at a 10%, 25%, and 50% sewage sludge amendment rate. The sewage sludge amendment was modified by the physicochemical properties of soil, thus increasing the availability of heavy metals in the soil and consequently increasing accumulation in plant parts. Cd, Pb, Ni, and Cu concentrations in roots were significantly higher in plants grown at 25% as compared to 50% SSA; however, Cr and Zn concentration was higher at 50% than 25% SSA. The concentrations of heavy metal showed a trend of Zn > Ni > Cu > Cr > Pb > Cd in roots and Zn > Cu > Ni > Cr > Pb > Cd in leaves. The only instance in which the chlorophyll content did not increase after the sewage sludge treatments was 50%. There were approximately 1.12-fold differences between the control and 50% sewage sludge application for chlorophyll content. The sewage sludge amendment led to a significant increase in Pb, Cr, Cd, Cu, Zn, and Ni concentrations of the soil. The heavy metal accumulation in the soil after the treatments did not exceed the limits for the land application of sewage sludge recommended by the US Environmental Protection Agency (US EPA). The increased concentration of heavy metals in the soil due to the sewage sludge amendment led to increases in heavy metal uptake and the leaf and root concentrations of Ni, Zn, Cd, Cu, Cr, Pb, and Zn in plants as compared to those grown on unamended soil. More accumulation occurred in roots and leaves than in shoots for most of the heavy metals. The concentrations of Cd, Cr, and Pb were more than the permissible limits of national standards in the edible portion of sugar beet grown on different sewage sludge amendment ratios. The study concludes that the sewage sludge amendment in the soil for growing sugar beet may not be a good option due to risk of contamination of Cr, Pb, and Cd.  相似文献   

5.
长江口潮沟大型底栖动物群落的初步研究   总被引:19,自引:2,他引:19  
通过对长江口崇明东滩潮沟系统与大型底栖无脊椎动物进行取样调查 ,研究了潮沟不同生境的底栖动物群落及其多样性 ,分析了潮沟生境异质性与底栖动物群落的关系。研究发现 :①潮沟剖面中出现明显的动物群落分带现象 ,从潮沟底、潮沟边滩到草滩 ,底栖动物种类、生活型组成和生活类群比例反映了河口潮滩潮沟底栖动物生态系列 ;②密度和生物量的分布皆为潮沟边滩 >草滩 >潮沟底 ,但密度与生物量的面上群 /面下群值格局却有不同 ,说明了密度和生物量的优势生活型和生活类群随潮沟生境的差异而变化 ;③潮沟系统 3种生境的多样性指数D ,H′和J值均为草滩 >潮沟边滩 >潮沟底 ,是潮沟系统生境结构分化的结果。潮沟底和潮沟边滩等特殊生境的存在 ,提高了淤泥质河口潮滩的生境异质性 ,说明了潮沟系统在维持河口生态系统底栖动物物种多样性中的重要作用。  相似文献   

6.
Abstract A growth experiment with native plants in pots exposed to natural environmental conditions evaluates the use of sewage sludge as a soil amendment in restoration of a southern California salt marsh. Sludge containing desirable organic matter but also undesirable heavy metal contaminants was mixed with a readily available matrix soil to reduce metal concentrations to levels below legal limits for land applications of sludge. Soil nutrient analysis revealed expected increases in total nitrogen and total phosphorus content with increasing sludge concentration. Soil metals analysis, however, revealed decreases in metal content with increased sludge concentration, a trend evidently caused by higher than expected metal content in the matrix soil. Five artificial soil mixtures ranging from 0 to 70% sludge were accompanied by natural wetland soil controls. Pots containing these soils were placed into a natural salt marsh. The pots were then planted with two native salt marsh plant species, Salicornia virginica and Frankenia grandifolia. Aboveground biomass was harvested after 12 months. Plant growth displayed no obvious change with increasing sludge concentration. Over the concentration ranges used, increased nutrient content did not stimulate plant growth and increased metal content did not inhibit plant growth. Plants grew better in natural wetland soil than in artificial soil mixtures, a trend probably caused by the substantially finer texture and higher organic content of natural soil. All sludge treatments differed more from the natural soil than from each other, implying that within the ranges examined, soil texture and organic content exerted more influence on plant growth than did metal or nutrient concentration. These results suggest that incorporating this sewage sludge in the soil of the restored salt marsh will neither benefit nor harm the plants that will live there and that greatest plant growth will be achieved by mixing the sludge with a fine‐grained matrix soil.  相似文献   

7.
Anaerobic granular and fixed-film reactors have been successfully operated for wastewater treatment at full scale for over two decades and represent a sustainable, energy-producing approach, which is increasingly being directed towards treatment of domestic sewage. Research over the past two decades, and significant operational experience, has demonstrated that there are no fundamental microbiological barriers to the implementation of AD for domestic sewage treatment in regions with warm and temperate climates. Despite this, the underlying microbiology of methanogenesis is not fully understood and novel groups of microbes have been identified in sludge, with unknown functions. The methanogenic process has recently been subject to systematic investigation using newly developed analytical and microbiological approaches. A combination of process monitoring, physiological, molecular microbiological and microscopic methods are beginning to generate a comprehensive, integrated data set at micro-organism, granule and reactor level and the current state of knowledge is reviewed here. Information on the formation of granules, on the relationship between reactor operating conditions and microbial consortia and on the impact of process changes on the microorganisms in reactors will, in future, enable the link between the processes occurring at microorganism level (scale ca. 1 μm–1 mm) and the processes occurring within reactors (scale >1 m), which will enhance the efficiency and applicability of anaerobic sewage treatment.  相似文献   

8.
Seed germination and seedling growth of the annual halophyte species Suaeda japonica Makino were investigated in response to variable salinity of sediment pore water. The germination percentage of S. japonica’s soft brown seeds, which are dominant among dimorphic seeds, decreased with an increase in salinity, although germination was still observed at 1200‐mM NaCl concentration. The germination percentage and germination speed observed in April were higher than those observed in December when treated with sediment water with 400–1200 mM of NaCl concentrations. These data suggest that S. japonica seedlings could be established on sediments that experience high temperatures. Germination recovery of S. japonica seeds transferred from 600‐mM NaCl containing sediment (seawater equivalent) was lowest among 0–1200‐mM NaCl treatments, implying the low tolerance of seawater conditions of S. japonica seeds. Seeds germinated in 900‐ to 1200‐mM NaCl medium showed poor growth, but survived, in hypersaline conditions, and exhibited improvement in growth upon transfer to lower salinity.  相似文献   

9.
The main aim of this study was to examine the influence of soil properties on the leaching of Cd, Cr, Cu, Ni, Pb, and Zn following the application of polluted sewage sludge to contrasting topsoils. Seventy agricultural soil samples from different parts of Spain were amended with a single dose of sewage sludge (equivalent to 50 t dry weight ha?1) and a column study was performed under controlled conditions. After two, four, and six months of incubation, 283 ml of distilled water (equivalent to a rainfall event of 25 l m?2) was applied. The leachates were then collected and analyzed for metals. For all of the soils considered, the pH was the most important parameter for the control of mobility metals (except for Cu, determined by the sand and soil organic carbon and only to a lesser extent by the soil pH r2 = 0.604, p < 0.001) and was negatively related to all of the studied metals. For Pb and Zn, soil pH was the single soil property explaining their mobility (r2 = 0.411, p < 0.001 for Pb; r2 = 0.713, p < 0.001 for Zn) while for Cd, Cr and Ni, EC, sand and silt also appeared in the statistical models (r2 = 0.753, p < 0.001 for Cd; r2 = 0.366, p < 0.001 for Cr; r2 = 0.784, p < 0.001 for Ni). In the basic soils, soil texture was the most important soil property controlling the mobility of metals (except for that of Pb, which it only weakly predicted). For the acidic-neutral soils, the soil pH was the most important soil property controlling metal mobility (except for that of Cr, which was mainly determined by the pseudo-total Cr content).  相似文献   

10.
人工樟子松—差不嗄蒿植被及其固沙作用   总被引:4,自引:2,他引:4  
李进 《生态学杂志》1992,11(3):17-21,27
植物固沙是整治沙漠和沙漠化土地的一种有效措施。人工植被的建立是植物固沙的必然结果。人工植被的演替、稳定性及其对环境的影响直接关系到流沙的固定程度。因此,本文旨在探讨人工樟子松(Pinus sylvestris var.  相似文献   

11.
目的:探讨色素内镜(CE)、窄带成像内镜(NBI)对大肠平坦型病变的检出及相关因素。方法:对2010年4月至6月来我院国际医学中心的276例患者行结肠镜检查,262例患者入选。先行常规白光模式插镜至回盲部,应用NBI模式退镜观察,检出平坦型病变后记录病变特征(包括数量、部位、形态、大小),然后再在常规白光模式下插镜至回盲部,应用0.25%靛胭脂染色后行色素内镜退镜观察,检出平坦型病变后记录病变特征,最后于病变活检。比较CE和NBI对平坦型病变的检出并分析相关因素。结果:262例患者中,共计检出病变198个,其中平坦型病变69个,检出率为34.8%。NBI检出平坦型病变51个(73.9%);CE检出平坦型病变69个(100%)(P<0.05)。NBI漏诊了18个平坦型病变,漏诊率为26.1%。NBI检出的平坦型病变平均大小为8.7±2.6mm,CE检出的平坦型病变平均大小为4.5±2.1mm(P<0.05)。NBI检出<5mm的平坦型病变5个(7.2%),CE检出<5mm的平坦型病变19个(27.5%)(P<0.05)。NBI检出的IIc型平坦型病变13个(18.8%),CE检出的IIc型平坦型病变25个(36...  相似文献   

12.
We studied the influence of inoculation with a mixture of three exotic arbuscular mycorrhizal (AM) fungi, Glomus intraradices Schenck & Smith, Glomus deserticola Trappe, Bloss. & Menge and Glomus mosseae (Nicol & Gerd.) Gerd. & Trappe, and the addition of composted sewage sludge (SS) on the activities of the antioxidant enzymes superoxide dismutase (SOD, EC 1.15.1.1) and total peroxidase (POX) and of shoot and root nitrate reductase (NR, EC 1.6.6.1) in Juniperus oxycedrus L. seedlings, an evergreen shrub, grown in a non-sterile soil under well-watered and drought-stress conditions. Both the inoculation with exotic AM fungi and the addition of composted SS stimulated significantly growth and the N and P contents in shoot tissues of J. oxycedrus with respect to the plants neither inoculated nor treated with composted SS that were either well-watered or droughted. Under drought-stress conditions, only inoculation with exotic AM fungi increased shoot and root NR activity (about 188% and 38%, respectively, with respect to the plants neither inoculated nor treated with composted SS). Drought increased the POX and SOD activities in both shoots of J. oxycedrus seedlings inoculated with exotic AM fungi and grown with composted SS, but the increase was less than in the plants neither inoculated nor treated with SS. Both the plants inoculated with exotic AM fungi and the plants grown with composted SS developed additional mechanisms to avoid oxidative damage produced under water-shortage conditions.  相似文献   

13.
研究不同污泥堆肥施用量(0、0.8%、2%、6%和10%)对高羊茅、黑麦草和早熟禾3种草坪草生长及光合特征的影响.结果表明: 污泥堆肥施用量为6%时效果最好.随污泥堆肥施用量的增加,高羊茅、黑麦草和早熟禾的株高、单叶面积和单株生物量均显著增加,根冠比显著降低,其中,株高增幅分别为64.9%~180.8%、97.3%~200.9%和39.1%~156.5%,单叶面积增幅分别为91.3%~417.4%、186.4%~394.9%和164.6%~508.3%,单株生物量增幅分别为333.4%~867.6%、138.4%~445.1%和316.3%~669.2%.随污泥堆肥施用量的增加,高羊茅净光合速率(Pn)、胞间CO2浓度(Ci)、蒸腾速率(Tr)和水分利用效率(WUE)呈先增加后降低的趋势;早熟禾Pn、Tr和WUE逐渐增加,Ci呈先增加后降低的趋势;黑麦草Pn和WUE逐渐增加,但其Ci和Tr呈先增加后降低的趋势.污泥堆肥施用使3种草叶绿素a、b和(a+b)含量增加,施用量>6%后叶绿素a、b和(a+b)含量下降,但叶绿素a/b变化不明显.
  相似文献   

14.
Summary Benzophenone (BPH) is an important intermediate in the production of medicines and cosmetics, but is also known as a xenoestrogen in its effect on mammals. We screened BPH-degrading microbes for potential bioremediation, and found degradation activity in the activated sludge of a sewage treatment plant in Hokkaido. A microbial strain with notable BPH-degrading activity (strain MU-1) was isolated from the sample. MU-1 degraded more than 95% of BPH (100–1000 ppm) as a sole carbon source within several days. However, it took a relatively long time for MU-1 to degrade a high concentration of BPH (5000–10,000 ppm), probably due to a toxic effect of BPH. The GC/MS analysis of the metabolites of BPH degradation suggested that BPH was degraded into hydrophilic compounds with very low molecular mass via conversion to phenol. The phylogenetic study based on rDNA sequences suggested that MU-1 was the black yeast Rhinocladiella aquaspersa. To our knowledge, this is the first report describing a BPH-degrading microbe.  相似文献   

15.
人为调节涨水过程促使家鱼自然繁殖的探讨   总被引:2,自引:0,他引:2  
曾祥胜 《生态学杂志》1990,9(4):20-23,28
在自然情况下,家鱼产卵活动除要求适宜的水温条件外,还需要所处江河涨水的刺激。而人为调节涨水过程就是为满足其繁殖条件所采取的一种人为补救措施。  相似文献   

16.
以陶粒和活性炭为填料的生物滴滤池系统,对人工合成的甲苯废气进行了净化处理试验,4个多月的运行结果表明(1)添加活性炭能提高填料柱的处理性能,陶粒和活性炭组成的复合填料能有效地处理含有甲苯的废气,当进气浓度为2.35g/m3时,去除率可达95%以上,填料柱对甲苯的去除能力为130g/m3·h;(2)在低浓度下,生物滴滤池的处理性能受传质过程控制;(3)填料柱出气通过循环液曝气处理后,废气中甲苯浓度进一步降低.  相似文献   

17.
Some fundamental natural-history traits of the endangered mud snail Cerithidea rhizophorarum were investigated for three years in an open, bare, sandy tidal flat located on the east of Shikoku Island in southwestern Japan. Our study demonstrated a highly aggregated distribution of younger snails and complicated differences in vertical migration patterns between younger and older snails that might have prevented comprehensive understanding of the precise demography of C. rhizophorarum in previous studies. From late summer, juveniles of the first-year cohorts appeared patchily at 12–16 cm lower tidal heights than snails of the oldest cohorts and reached 5.0–7.5 mm in mean shell length by the first mid-autumn. In the second year, juveniles gradually moved upward and appeared at higher tidal heights. The second-year cohorts reached 15.6–19.1 mm in mean shell length by the end of the second autumn and converged into the oldest cohorts during the third year or later. Our results suggest that C. rhizophorarum matures sexually and starts reproduction from the fourth summer at the earliest. On the other hand, older snails showed a similar seasonal migration pattern every year—downward movement in summer and upward movement in autumn—probably associated with their reproductive activity and/or a seasonal change in the maximum tidal height. For conservation of C. rhizophorarum, it is very important to preserve both the higher area as a main habitat for older snails and the lower tidal flat as the nursery ground.  相似文献   

18.
A concept model of regional risk was constructed for the characteristics of ecosystems alongside the Qinghai-Tibet highway and railway based on the MLP (Multilayer perceptron) model. Seven indices such as snow hazard, drought hazard, and landslide were selected in order to evaluate the integrated ecological risk of the ecosystems along the study area. Results show that the Qaidam montane desert zone had the greatest average risk value (4.26), followed by the Golog-Nagqu high-cold scrub meadow zone (2.80) and the East Qinghai and Qilian montane steppe zone (2.73) among the ecosystems within the six natural zones within the study region. As far as land cover types are concerned, the top three ecological risk values appear in the needle-leaved forest (4.31), desert (4.12), and land without vegetation (3.62), which are higher than those in the other seven types in the study site. Although the risk values are influenced by natural factors and human activities, they are more strongly controlled by natural factors. According to the ecological risk characteristics, the ecosystems within the study area are subdivided into four subregions, including the Qaidam basin region (high risk), the Xidatan to Damxung region (moderate risk), and the Eastern Qinghai-Qilian (slight risk) and Southern Xizang (Tibet) region (slighter risk).  相似文献   

19.
On a moderately protected intertidal sand flat in west Kyushu, Japan, most of the population of the cirolanid isopodEurydice nipponica Bruce & Jones (89%–100%) was found in the zones occupied by the thalassinidean ghost shrimpCallianassa japonica Ortmann in July, August and December 1980.C. japonica later extensively expanded its habitat, and in July 1984, when almost the whole sand flat had been densely populated byC. japonica, the range of the distribution ofE. nipponica was the same as that ofC. japonica with a density about 10 times greater than in July 1980. The occurrence ofE. nipponica has previously been recorded from several exposed sandy beaches as well as their adjacent subtidal areas of well oxygenated sands along the coast of Kyushu, but not on more protected shores like the present sand flat. It is suggested thatC. japonica, through its bioturbating activities, produces sediment characteristics approximating those of the exposed sandy beaches which are the preferred habitat ofE. nipponica. It is supposed thatE. nipponica is a facultative commensal ofC. japonica. In a field experiment to excludeC. japonica and to detect its positive influence onE. nipponica, the densities ofE. nipponica were found to be lower in the experimental plots than in the intact plots. Statistically, however, the difference was only weakly significant, and the possible reasons for this are discussed.  相似文献   

20.
YUN  Jae-Su 《Entomological Research》2005,35(4):199-205
ABSTRACT This study was carried out to investigate pathogenicity of cordyceps on the silkworm larva, Bombyx mori . For experiment, Cordyceps, Pacillomyces sp. strain collected from Chiak mountain area in Gangwon Province and Pacillomyces japonica collected from dead silkworm larva at the rearing room in Sangju National University were used. Spores of cordyceps were propagated on sterile PDA (potato dextrose agar 39g, water 1,000mL) at 25°C for 21 days. Spores of cordyceps isolated from media were inoculated on integuments of 3rd instar newly exuviated silkworm for pathogenicity on the silkworm larvae. The cordyceps used in this study was highly infectious to the silkworms. Virulence of cordyceps was different depending on species. Pacillomyces japonica was the most efficacious with 70% mortality on silkworm larvae. Cordyceps had adverse effect on the overall rearing from larval period to mounting of matured silkworm larvae, cocoon making, pupation and moth emergence. The result suggests that cordyceps used in this study may be useful for the tracking of biocontrol.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号