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1.
江苏农村"三格式"化粪池污水处理效果评价   总被引:15,自引:0,他引:15  
"三格式"化粪池是江苏农村改厕中普遍使用的1种污水处理方式,约占全省农村卫生厕所的50%,其处理效果直接影响农村水环境质量.在江苏省9个县(市、区)中选取168户农民正常使用的"三格式"化粪池作为研究对象,于2006年6月至8月每隔5 d、连续3次分别在其进、出口采取水样进行监测、分析.结果表明,"三格式"化粪池对CODCr、TN和TP的去除率分别为48.51%、6.83%和23.92%;苏南地区好于苏中地区,苏北地区最差;"三格式"化粪池处理效果差于沼气化粪池,处理后的尾水未达国家污水排放标准,排入环境会造成较大影响.  相似文献   

2.
《生态毒理学报》2007,2(2):189-189
<正>1.稿件用A4纸打印.2.按GB7713-87(《科学技术报告、学位论文和学术论文的编写格式》)规定,本刊要求论  相似文献   

3.
探讨了在FoxBASE^ /FoxPRO环境中数据质量保证和质量控制方法,并介绍了自行设计的E.O.E系统功能,其方法包括主观和客观两大方面。主观方面包括数据灵入的屏幕格式、系统的易理解性、良好的人一机会话功能等,客观方面包括:录入时的数据质量控制,即数据录入的编辑格式和数据范围检验;录入后的数据质量检验,即比较查错法、分层控制查错法和分层控制-比较查错法三种。  相似文献   

4.
<正>1.稿件用A4纸打印.2.按GB7713-87(《科学技术报告、学位论文和学术论文的编写格式》)规定,本刊要求论文包括以下3部分:前置部分、主体部分和附录(如果有的话).其中前置部分包括题名,作者姓名、单位、邮编(统称作者信息项),中、英文摘要及关键词  相似文献   

5.
《生态毒理学报》2009,4(5):744-744
<正>1.稿件用A4纸打印.2.按GB7713-87(《科学技术报告、学位论文和学术论文的编写格式》)规定,本刊要求论文包括以下3部分:前置部分、主体部分和附录(如果有的话).其中前置部分包括题名,作者姓名、单位、邮编(统称作者信息项),中、英文摘要及关键词;主体部分包括引言、正文、致  相似文献   

6.
来稿须知     
1.来稿请按GB7713—87《科学技术报告、学位论文和学术论文编写格式》撰写,可参看本刊1994年第3期附页.2.来稿一式两份(包括一份复印件),请用16开400字稿纸抄写(打字稿用五号字按38行×38字打印);图表的绘制与设计应布局合理,大小适中,照片图要求图像清晰、层次分明、反差适中,尽量采用黑白照片,图表应尽量精简或改用文字说明.  相似文献   

7.
阐述了建立生态站空间历史数据库的重要性和操作步骤,给出了建立图档文件的格式和实例,其图档格式:图档日志,图档说明,变量,矢量文件等。  相似文献   

8.
简要介绍了封丘生态站参考美国LTERN的Sevilleta生态站和An-drews生态站模式,结合本站的实际情况对数据文档文件、课题、专著、内部资料、地图等制定的编码格式,同时介绍了中国生态研究网络(CERN)秘书处对数据文档文件所作的分类编码的统一格式,着重探讨了CERN的统一编码和封丘站碛有编码之间的转换和连结。  相似文献   

9.
介绍了C语言格式式化输出类操作函数,对该类函数的实现方式和C语言可变参数的工作原理进行了较为详细的阐述,同时,构造了一个方便通用的格式化输出函数,为数据数据格式化操作提供了一条灵活便捷有效的处理途径.  相似文献   

10.
《产业与环境》2005,27(2):84-84
环境署金融举措的Valuesto Value报告在6月召开的联合国全球契约领导人峰会上出版.该报告作为一个不断更新的报告,收集了论文和会议文件.将来,使用者将可获得相同格式的补充材料.主题部分包括“可持续性管理、报告和指标”、“民间社会对于可持续金融的看法”、“资产管理”、“气候变化”和地区举措,配套的CD-ROM中包含了pdf格式的报告,以及很多其他与金融与可持续性相关的文件.  相似文献   

11.
土壤中铍的存在形态及提取研究   总被引:3,自引:0,他引:3  
本文对三种不同类型土壤中铍的存在形态及提取进行了研究,并做了原土铍和外加铍形态提取对照试验,选择了各形态合适的提取剂,建立了土壤铍形态连续提取方法,对提取机理和形态分布规律进行了探讨。此外,还对土壤提取的有效铍与盆栽植物吸收铍量的相关性进行了初步研究。  相似文献   

12.
以连续提取法研究了我国南方主要酸性土壤铝的形态及其分布特点,探讨了不同铝形态之间的关系及其与母质、成土过程、环境条件的联系。还研究了土壤酸化对铝形态转化的影响.并以连续提取法提取的三种铝形态(交换性铝、活性羟基铝,有机络合态铝)来讨论现今常用的Al。(Tamm溶液提取)和Ald(DCB溶液提取)所可能包含的实际土壤铝形态,分析表明,Al0和Ald无明确的形态意义,只是上种由操作定义的多形态组成的混合物。  相似文献   

13.
二种高硫煤中硫氮化学形态的研究   总被引:2,自引:0,他引:2  
朱珍平  冯大明 《环境化学》1995,14(6):483-488
利用XPS技术研究了贵定煤和西班牙Mequienza煤中硫和氮化学形态的分布,并结合硫K-边XANES和Mossbauer谱着重考察贵定煤中硫化学形态。结果表明,贵定煤中含硫化合物主要以噻吩形态存在,其次为有机硫化物;而Mequienza煤中以有机硫化物含量最大,噻吩硫次之,有关含氮化合物,Mequienza煤以吡咯和吡啶氮为主,但在贵定煤中观察到较大浓度的氧化氮化合物。  相似文献   

14.
宝鸡城市街尘、土壤及河流沉积物重金属形态迁移特征   总被引:1,自引:0,他引:1  
在宝鸡城市街尘、土壤及河流沉积物基本理化性质和重金属元素含量分析的基础上,重点研究了重金属元素在街尘、土壤及河流沉积物中的赋存形态和迁移特征.结果表明:在街尘中Cu主要以可氧化态和残余态形式存在,Pb主要以可还原态和可氧化态形式存在,Zn和Cd主要以乙酸可提取态形式存在,Mn、Fe、Co、Ni和Cr主要以残余态形式存在...  相似文献   

15.
何孟常  杨居荣 《环境化学》2001,20(2):124-128
在体外消化酶模拟条件下,对小麦籽实中Cd,Pb蛋白质结合体的稳定性进行了研究.结果表明:小麦籽实中存在的表观分子量为54.5×103和5.5×103的蛋白质-Cd,Pb结合体,在体外胃蛋白酶和胰蛋白酶消化后,蛋白质结构发生变化.特别是分子量为54.5×103的Cd,Pb-蛋白质结合体不稳定,容易被胰蛋白酶分解,变成分子量为5.5×103的稳定的Cd,Pb-蛋白质结合体或更小的多肽.  相似文献   

16.
The radiate-accretive growth process of the spongeHaliclona oculata, under different environmental conditions, is simulated in a two-dimensional model with fractal modelling techniques. In this model material is added in layers to the object, and growth velocities attain highest values at its protrusions. With this model some aspects of the growth process can be explained. It is possible to simulate thin-branching growth forms, which are normally found under sheltered conditions, and plate-like forms, which are typical for sites more exposed to water movement. These simulated forms are compared with actual growth forms in order to test the validity of the model.  相似文献   

17.
上覆水中磷被结合到底泥中时,不同形态磷的数量将会改变, 由此导致磷的释放能力和生物有效性被显著改变.以富营养化河道上覆水和底泥为材料,考察了静态条件下,底泥中不同形态磷的变化规律及其对磷的生物有效性的影响.结果表明, 潜在活性磷(PMP)含量显著增加,NH4Cl-P、BD-P、NaOH-nrP分别增加了297.68%、1O.73%、30.49%.难释放态磷则基本保持不变.潜在活性磷对生物有效磷的形成具有显著的影响,4种生物有效磷中的3种(WSP、Olsen-P、AAP)均与其在a<0.01水平上显著正相关,并且其对AAP形成的影响最为显著.因此推测,静态条件下,当上覆水中磷向底泥迁移时,首先会形成潜在活性磷和生物有效磷.  相似文献   

18.
外生菌根真菌对油松幼苗根际土壤重金属赋存的影响   总被引:7,自引:0,他引:7  
油松幼苗接种菌根盆栽试验表明,外生菌根真菌对油松根际土壤重金属铜、镉的赋存形态产生显著影响.与普通根际相比,菌根际土壤中交换态铜、镉含量显著下降,而有机结合态含量则显著增加.菌根际土壤重金属形态呈现出由疏松结合态向紧密结合态转化的趋势.接种菌根显著降低根际重金属的生物有效性,缓解重金属对寄主植物的毒害作用.  相似文献   

19.
Harrison KA  Bol R  Bardgett RD 《Ecology》2007,88(4):989-999
The growing awareness that plants might use a variety of nitrogen (N) forms, both organic and inorganic, has raised questions about the role of resource partitioning in plant communities. It has been proposed that coexisting plant species might be able to partition a limited N pool, thereby avoiding competition for resources, through the uptake of different chemical forms of N. In this study, we used in situ stable isotope labeling techniques to assess whether coexisting plant species of a temperate grassland (England, UK) display preferences for different chemical forms of N, including inorganic N and a range of amino acids of varying complexity. We also tested whether plants and soil microbes differ in their preference for different N forms, thereby relaxing competition for this limiting resource. We examined preferential uptake of a range of 13C15N-labeled amino acids (glycine, serine, and phenylalanine) and 15N-labeled inorganic N by coexisting grass species and soil microbes in the field. Our data show that while coexisting plant species simultaneously take up a variety of N forms, including inorganic N and amino acids, they all showed a preference for inorganic N over organic N and for simple over the more complex amino acids. Soil microbes outcompeted plants for added N after 50 hours, but in the long-term (33 days) the proportion of added 15N contained in the plant pool increased for all N forms except for phenylalanine, while the proportion in the microbial biomass declined relative to the first harvest. These findings suggest that in the longer-term plants become more effective competitors for added 15N. This might be due to microbial turnover releasing 15N back into the plant-soil system or to the mineralization and subsequent plant uptake of 15N transferred initially to the organic matter pool. We found no evidence that soil microbes preferentially utilize any of the N forms added, despite previous studies showing that microbial preferences for N forms vary over time. Our data suggest that coexisting plants can outcompete microbes for a variety of N forms, but that such plant species show similar preferences for inorganic over organic N.  相似文献   

20.
Along the temperate Pacific coast of North America, the actiniarian sea anemone Anthopleura elegantissima exhibits two discrete life-history phenotypes. Although both forms sexually produce planula larvae, the clonal morph can also asexually propagate by fission, whereas the solitary morph does not. Whether the two forms constitute one or two species has long been contested. Hand originally designated the two forms as conspecifics, whereas Francis – on the basis of differences in microhabitat, biogeographic range and phenotypic frequencies – argued that the two forms constituted a sibling-species pair. From the results of an electrophoretic survey in which they pooled allelic frequencies across several geographic locations, Smith and Potts subsequently argued that the two forms were not genetically differentiated, and therefore represented a single species. We re-examined the relationship between the forms electrophoretically, substantially extending the geographic range and doubling the sample sizes beyond those used by Smith and Potts, and not pooling allelic frequencies in our analyses. Our analysis of patterns of genetic variation at ten highly polymorphic allozyme loci shows that although no fixed genetic differences distinguish the two forms, there are significant differences in allele frequencies between clonal and solitary A.␣elegantissima at every site we sampled throughout their range of sympatry (over 1000 km); within each form, however, there is little detectable genetic differentiation among populations. We therefore conclude that the two forms represent recently reproductively isolated taxa, and propose that the clonal form retain the binomial A. elegantissima (Brandt, 1835), whereas the solitary form be described and named a new species, Anthopleura sp. Received: 28 August 1996 / Accepted: 25 September 1996  相似文献   

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