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Search Results: 1 - 10 of 67696 matches for " 谭永钦 "
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Researches on weed niche in turf
草坪杂草生态位研究

TAN Yong-Qin,

生态学报 , 2004,
Abstract: Niche is an important theoretic problem in studying plant population and community ecology. Niche breadth may be a measure of turfs' using diversity to environmental resource and it is a response of weeds to ecological niche. Niche-overlap is a measure to display the similarity of plant interspecies bionomics. Studies on the important value, niche breadth, and niche overlap of different weeds in turf can reveal the ecological demand similarity of different weeds, and can forecast the trend of reciprocal affect between different kings of weeds. So it can give some guide in using herbicide reasonably and get to a double-aim of dropping cost in maintaining turf and protecting the environment. When turf is identified as a healthy ecosystem, this turf ecosystem remains resistant or resilient to the long-term and unexpected disturbance caused by natural or human activities. Long-term application of a certain herbicide let a variation of weed populations in turf. It increases the difficulty controlling weeds effectively. Therefore, it is a hot problem for us to solve. In this paper, different kinds of turfs in Wuhan region were exemplified systematically. In the turfs in Wuhan region, 20 sites under different ecological condition were surveyed in detail with seven scales by visua- lization of weed dominance to rape to obtain the important value of 20 main weeds. The species niche breadth and niche overlap were calculated on the basis of the investigation. The results show that Alopecurus aequalis (0.559), Stellaria media (0.4341), Avena fatua (0.3214), Gnaphalium multiceps (0.2909), Galium apaine (0.2747), Ranunculus arvensis (0.2686), and Mazus japonicus (Thunb) O. Ltze (0.2474) have bigger value in ecological niche. The bigger value of the weeds showed that they have wider ecological-amplitude, and they can adapt to more kinds of environment. Because different weeds have different ecological annidation, they have different niche overlap value. The more ecological niche overlaps value show that the more same ecological resource can be used, and they must compete more fierily. Different weeds can be classfied according to their overlap value. For example, Galium apaine, Avena fatua, and Veronica persica belong to the same class. Galium apaine and Veronica persica have a bigger overlap value than Avena fatua. Alopecurus aequalis, Stellaria media, Mazus japonicus (Thunb) O. Ltze., Gnaphalium multiceps, Cardamine hirsuta L., Ranunculus arvensis and Poa annual can be classed together. These weeds always occur in similar spaces and have a large number. As compared with those of the other species, the niche overlaps between Galium apaine, Veronica persica, and Avena fatua were higher. The bigger value of weeds showed that they have wider ecological-amplitude, and they can adapt to more kinds of environment.Niche breadth reflects weeds' variety or specialization level in using nature resource. In the ordinary way weeds having a bigger niche breadth immolate th
MgO和La2O3对Ni/Al2O3上CO吸附影响的红外光谱研究
维衍,,
催化学报 , 1989,
Abstract: ?
草坪杂草生态位研究
,张国安?,郭尔祥?
生态学报 , 2004,
Abstract: 调查研究草坪杂草的重要值、生态位宽度、以及不同种类杂草之间的生态位重叠值,能够揭示杂草种间生态相似关系,能够预测杂草之间相互影响的趋势。利用杂草种间的相互制约关系,可以指导合理地使用除草剂,从而达到降低草坪养护成本,保护环境的双重效果。以武汉市区多种不同种类草坪为研究对象,对该地区草坪主要杂草进行了系统调查,通过七级目测法,计算了草坪20种主要杂草的重要值,并计测了它们的生态位宽度和生态位重叠值。结果表明,看麦娘(alopecurusaequalis),牛蘩缕(stellariamedia),野燕麦(avenafatua),猪殃殃(galiumaparine),一年蓬(erigeronannuus),鼠麴草(gnaphaliummulticeps),毛茛(ranunculusarevensis),通泉草(mazusjaponicus)等杂草的实际生态位比较宽,它们是本地区草坪的主要杂草。而猪殃殃(galiumaparine),婆婆纳(veronicapersica),野燕麦(avenafatua)等杂草间的生态位重叠值大。杂草生态位宽度大的杂草以牺牲对局域范围内资源的利用效率来换取对大范围内资源的利用能力。
黄花蒿对紫茎泽兰竞争效应的影响
Influence of Artemisia annua on the competition effect of Eupatorium adenophorum

孙娜娜,,马洪菊,周兴苗,
- , 2015,
Abstract: 采用复合De Wit取代试验设计方法,分析入侵杂草紫茎泽兰(Eupatorium adenophorum)与本土植物黄花蒿(Artemisia annua)的竞争关系,观察不同种植密度和种植比例对紫茎泽兰生长特性的影响。结果表明: 在紫茎泽兰和黄花蒿混种样地中,紫茎泽兰相对产量(RYg)和相对密度(RDg)均小于1; 随着黄花蒿混种比例的增加,紫茎泽兰的RYg和RDg均逐渐减小,同时紫茎泽兰的茎宽、分枝数、生物量逐渐降低; 紫茎泽兰与黄花蒿之间的竞争大于紫茎泽兰的种内竞争,黄花蒿的存在抑制了紫茎泽兰种群数量的扩增; 在黄花蒿混种比例较高的情况下,随着种群密度的增加,紫茎泽兰的根冠比逐渐降低,同时紫茎泽兰的株高逐渐增加; 紫茎泽兰能采取地上优先生长策略应对黄花蒿的强大竞争压力; 在紫茎泽兰入侵早期利用黄花蒿进行替代控制,可获得较好的防治效果。
The competition relation between Eupatorium adenophorum and Artemisia annua was studied by using the multiple De Wit replacement series design method, which discussed the effects of growing character of E.adenophorum in different planting densities and mixture proportions. The results showed that the relative yield (RYg) and the relative density (RDg) were less than 1 in mixture sample area between E.adenophorum and A.annua; with the increase of the mixture proportion of A.annua,the RYg and RDg of E.adenophorum were gradually decreasing, and stem diameter, branch number and biomass were also decreasing, which implied that the competition between E.adenophorum and A.annua was severer than intraspecific competition of E.adenophorum and the population expansion of E.adenophorum was restrained when A.annua existed. With the increase of the population density under the circumstance of higher mixture proportion of A.annua, root/shoot radio of E.adenophorum had a trend of reduction,but plant height of E.adenophorum had a trend of increase, which suggested that E.adenophorum had to adopt the allocation of resources model, namely, the strategy of the ground priority growth in response to stronger pressure of competition of A.annua. Based on the above results, we should replace E.adenophorum with A.annua at the early stages of invasion to have a good effect on the control of E.adenophorum.
露天矿滑坡体的探地雷达检测技术
,,,,吴治涛
煤炭学报 , 2011,
Abstract: 提出了使用探地雷达检测露天矿山边坡的方法。通过探地雷达探测实际露天矿山边坡,反演分析解释沿测线的雷达图像,结合雷达正演模拟计算,对比Janbu法稳定性计算结果发现:雷达探测边坡内部构造的图像与地表出露的滑坡特征相符,与稳定性计算形成的圆弧滑坡面也基本吻合,而且雷达探测结果还揭示了台阶边坡内部潜在的地质缺陷。探测结果证明,探地雷达检测露天矿山边坡内部地质构造和缺陷是可行的。
四川盆地北部二叠系-三叠系沉积相与沉积演化
,熊治富,刘雁婷,季春辉,邓金花,,都占海
科技导报 , 2014, DOI: 10.3981/j.issn.1000-7857.2014.06.007
Abstract: 通过钻井、露头、地震等资料分析,对四川盆地北部地区二三叠系沉积相进行详细研究,识别出碳酸盐岩台地、碳酸盐岩缓坡两大沉积体系,指出研究区二三叠系沉积具有典型的从碳酸盐岩缓坡演化为碳酸盐岩镶边台地沉积的演化过程,中二叠统栖霞组、茅口组及上二叠统吴家坪组发育碳酸盐岩缓坡沉积,上二叠统长兴组过渡为碳酸盐岩镶边台地,飞仙关组沉积末期全区演化为均一化台地。研究成果对本区油气勘探具有一定的参考价值。
私法自治中的国家强制

中外法学 , 2001,
Abstract:
大陆法系国家民法典编纂若干问题探讨

比较法研究 , 2009,
Abstract:
民法的积累、选择与创新

比较法研究 , 2006,
Abstract:
辛勤笔耕传播火种

中国图书馆学报 , 1983,
Abstract:
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