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 62 毫秒
1.
崔芳  袁博 《中国农学通报》2012,28(5):306-311
为了量化评价渭河宝鸡段水质现状,并对污染趋势进行分析,为水环境保护及管理提供依据,应用改进的灰色关联法,在试验数据和监测结果基础上,对BOD5、CODCCr、CODMn、NH3-N、TP、TN 6个水质指标进行定量计算和评价。结果表明,渭河宝鸡段水质现状总体良好,评价断面水质达到或超过相应功能区水质标准,其中林家村断面达到Ⅱ类水质标准,胜利桥、卧龙寺桥和常兴桥断面的水质可达到Ⅲ类水质标准,虢镇桥、蔡家坡桥的水质较差,为Ⅳ类水质。同时,评价结果还表明,有机污染是水质好坏的限制性因子。采用改进的灰色关联度分析法,具有准确性、客观性的特点,对渭河宝鸡段水质评价效果良好。  相似文献   

2.
渭河宝鸡段水质评价及变化趋势分析   总被引:2,自引:2,他引:0  
易文利 《中国农学通报》2010,26(24):353-357
对渭河宝鸡段水质污染情况及变化趋势做出评价,为宝鸡市渭河治理、保护及建设提供一定参考依据。根据2007~2009年渭河宝鸡段6个断面的水质监测资料,采用模糊综合评价法对其进行综合评价,应用秩相关系数法对主要的3个断面的水质在时间上(2002~2009年)的变化趋势进行定量分析。结果表明,所有断面水质达到功能区所要求的水质类别,但存在一定的有机污染;在时间上,渭河宝鸡段污染情况呈下降趋势;在空间上,林家村断面的水质情况最好,胜利桥、常兴桥和卧龙寺断面次之,虢镇桥和蔡家坡断面最差。  相似文献   

3.
灰色聚类法在重庆北碚区境内支流河流水质评价中的应用   总被引:2,自引:0,他引:2  
以重庆市北碚区境内的3条主要支流河流璧北河、磨滩河和黑水河为研究对象,运用灰色聚类法对该3条河流的5个监测断面和11个污染因子进行了综合评价。评价结果表明,北碚区区支流河流各断面水质状况差别较大,龙凤河口和西西桥两个断面由于工业废水和生活污水的大量排放,污染较严重,3次监测结果均为Ⅴ类水质,其他3个断面—堰塘坎、偏岩、水土水质均达到了Ⅱ类或Ⅲ类标准。评价结果为污染控制提供了科学依据。  相似文献   

4.
基于灰色聚类法的大庆市油田开发区湿地水环境质量评价   总被引:3,自引:0,他引:3  
探讨灰色聚类法在水质评价中的科学性,为大庆市油田开发区湿地水环境质量评价提供了方法学参考,并为松花江中下游水环境保护提供了相关依据。首先,分析了灰色聚类法、单因子污染指数法的基本原理,然后采用相关数学方法对各监测断面水质监测数据进行评价。结果表明,除万宝泡东北侧进水口、出水口桥下的水质为II类水质标准,龙凤湿地安肇新河为III类水质标准,水质较好外,其余监测点水质均为V类水质标准,水体污染严重。研究实例表明,相对于单因子污染指数法,灰色聚类法对水环境质量数据具有更高的利用能力及客观性。由于大庆市油田开发区周边有很多重要的湿地保护区,因此大庆市油田开发区湿地水质污染问题已不容忽视。  相似文献   

5.
杜鑫  吴钢  许东 《中国农学通报》2013,29(32):221-224
选用合适的模型提高预测的精度和可靠性,为区域水环境管理提供科学依据,是水质预测要解决的关键问题。为了解决这一问题,根据辽河流域的实际,运用自回归滑动平均(ARMA)模型对辽河流域东陵大桥监测断面CODMn的水质变化趋势进行预测。结果表明:综合自相关函数、偏相关函数以及BIC原则,ARMA(1,1)模型能够更好地用于东陵大桥断面水质预测。拟合结果显示,相对误差在2.60%~25.98%之间,平均相对误差为13.69%,说明该模型能够充分利用近期水质资料信息,以精确预测未来水质变化趋势。而对东陵大桥监测断面CODMn的预测显示,未来CODMn呈现出增长态势,辽宁水环境管理任务仍然很重。最后,就ARMA模型应用于水质预测的问题和发展方向进行了探讨。  相似文献   

6.
云南丽江适栽蓝莓品种的筛选试验初报   总被引:1,自引:0,他引:1  
为了解不同蓝莓品种在云南丽江的丰产性和适应性,筛选出适合本地区种植的优质、高产蓝莓新品种,本研究通过8个兔眼蓝莓品种进行田间比较试验,采用灰色关联分析法对供试品种的结果枝数、每枝结果数、株高、单果重、单株1年生枝数、冠幅和单株产量等7个主要农艺性状进行灰色关联综合评价。结果表明:以单株产量为参考数列,其他性状构成被比较数列,灰色关联序依次是结果枝数每枝结果数株高单果重单株1年生枝冠幅。以理想品种为参考数列,其他品种为被比较数列,灰色关联序依次是'芭尔得温’'粉蓝’'灿烂’'杰兔’'顶峰’'园蓝’'乡铃’'梯芙蓝’。因此,以灰色关联分析法评估选出的'芭尔得温’、'粉蓝’、'灿烂’、'杰兔’4个品种,综合性状表现优,适合在丽江地区推广种植。  相似文献   

7.
模糊综合评价法在北碚主要支流河流水质评价中的运用   总被引:1,自引:0,他引:1  
摘要:本文以重庆市北碚区的三条主要支流河流璧北河、磨滩河、黑水河为研究对象,运用模糊数学综合评价模型对5个监测断面和11个污染因子进行了综合评价。评价结果表明,5个断面水质具有明显的季节变化,并表明黑水河流域地表水质总体状况最好,除了偏岩断面2月份为Ⅲ级水质外,均处于Ⅰ级和Ⅱ级,符合功能水环境质量标准;而磨滩河的水质最差,甚至出现了劣Ⅴ级水质,可见其污染严重,需要治理;璧北河水质较好,2月份为Ⅳ类水质,5月份为Ⅲ级水质,8月份的河水水质较好,为Ⅱ类。评价结果为污染控制提供了科学依据。  相似文献   

8.
通过介绍灰色系统理论中关联度权重分析的基本原理和方法,并以杂交小麦区试资料为例探讨了性状纲化值、性状之间的绝对值、关联系数等相互的换算关系,明确了灰色关联权重分析法在农作物新品种综合评估中的应用。结果表明,产量的权重最大,其次是容重,综合评估结果与品种的实际表现一致,依次是中麦875、周麦32、秋乐2122。  相似文献   

9.
为了了解不同蓝莓品种在云南丽江的丰产性和适应性,筛选出适合本地区种植的优质、高产蓝莓新品种,本研究通过8个兔眼蓝莓品种进行田间比较试验,采用灰色关联分析法对供试品种的结果枝数、每枝结果数、株高、单果重、单株一年生枝数、冠幅和单株产量等7个主要农艺性状进行灰色关联综合评价。以单株产量为参考数列,其他性状构成被比较数列,灰色关联序依次是:结果枝数>每枝结果数>株高>单果重>单株一年生枝>冠幅。以理想品种为参考数列,其他品种为被比较数列,灰色关联序依次是‘芭尔得温’>‘粉蓝’>‘灿烂’>‘杰兔’>‘顶峰’>‘园蓝’>‘乡铃’>‘梯芙蓝’。因此,以灰色关联分析法评估选出的‘芭尔得温’、‘粉蓝’、‘灿烂’、‘杰兔’4个品种,综合性状表现优,适合在丽江地区推广种植。  相似文献   

10.
怀化市区水体污染现状研究   总被引:1,自引:0,他引:1  
为了保护怀化市区水体环境质量,为怀化市生态宜居城市建设提供科学依据,对流经怀化市区的舞水河支流太平溪水质分平水期、枯水期2个时期进行了实地调查与监测,并结合太平溪历年的水质状况,对其水质进行了综合评价。结果表明,太平溪各个断面TP和NH3-N含量明显偏高,均超出国家Ⅴ类水质标准,说明太平溪存在明显的生活污水污染;水体中DO含量低,有些断面水质未达到的Ⅳ类水质标准,有些未达到Ⅴ类水质标准;太平溪汇入舞水河后的湾滩断面,其水体中NH3-N、TP含量均要高于汇入舞水河之前的陈家断面,说明太平溪水体污染对舞水河水质产生了一定的影响;结合太平溪历年水质监测数据分析发现,水体中DO的含量持续降低,而TP含量却持续增高,水体污染日益严重。因此,进一步加强太平溪水体的综合治理对舞水河的保护以及怀化市建设生态宜居城市意义重大。  相似文献   

11.
Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.  相似文献   

12.
Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.  相似文献   

13.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.  相似文献   

14.
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...  相似文献   

15.
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...  相似文献   

16.
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.  相似文献   

17.
T. Visser  E. H. Oost 《Euphytica》1981,30(1):65-70
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.  相似文献   

18.
[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...  相似文献   

19.
E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf 1) and recessive for the other (Rf 2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph 3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf 1(one of two dominant additive genes controlling early season leafing out) indicated that Rf 1and Rf 2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf 1, and 0.15 for Lf 1-Sph 3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph 3.It is suggested that competitive disadvantage of lf 1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph 3. Poor performance of lf 1- (and possibly lf 2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).  相似文献   

20.
Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.  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