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浑善达克沙地是我国北方干旱半干旱区的主要沙地和严重荒漠化地区之一。同时也是我国内陆沙尘的主要源区之一。研究当地植物对沙地环境的适应方式有助于当地的荒漠化治理,加快生态环境恢复。本文应用(温室和野外)实验生态学方法研究了沙地植物对水分、沙埋和养分异质性环境的生态适应对策。 浑善达克沙地属于半干旱区域。在一次降雨过后,适合植物生长的湿沙层逐渐下降,或者说不适合植物生长的干沙层逐渐加厚。为了能够有效地从沙层中获得水分,植物的根系的伸长的速度必须大于湿沙层下降的速度。因此,当地分布的植物的根系则应该具有相应的形态、生长和生物量投资方面的可塑性。羊柴(Hedysarum laeve Maxim. (Leguminosae) )是当地的主要半灌木和固沙植物。我们研究了羊柴幼苗对不同土壤含水量和不同模拟降雨量的反应格局,以及移动沙丘生长季节的土壤含水量变动规律。发现,大于3%土壤含水量适合羊柴幼苗生长。最适土壤含水量为12%-20% 。在生长季节早期,羊柴幼苗比较容易在沙丘上定居。如果没有充分的后续降雨的话,萌发后的幼苗在沙丘顶部、落沙坡中部和后部定居比较困难。降雨量越大,根系越深、总根长越大、根系直径越大、侧根越多、根冠比越低。 在干旱半干旱区域的沙地,种子萌发的时间和地点对于植物的定居和存活具有关键作用。通过温室实验,研究了小叶锦鸡儿和羊柴的种子萌发和出苗对不同深度的沙埋的反应,及其与种子大小的关联。结果表明,小叶锦鸡儿和羊柴的种子萌发和出苗对浑善达克沙地的自然生境表现出相似的生态适应。这两个种的种子萌发的适宜温度为10-15ºC, 这是当地春季的平均温度。由于这两个种的种子萌发是光敏感的,所以它们的种子萌发受土壤含水量和光照强度二者之间的平衡调节。2 cm 的较浅沙埋最有利于种子萌发和出苗。种子埋得越深,种子的萌发率和出苗率越低,更多的种子受胁迫休眠保存在土壤中作为种子库。不同大小的种子的不同萌发能力也是一种重要的生态适应,这可以调节种子在合适的时间和合适的沙埋深度萌发和出苗。 冰草(Agropyron cristatum (L.) Gaertn)是浑善达克沙地植物群落中占优势的多年生根茎草本植物之一。种子在合适的地点和时间萌发以及幼苗在合适的地点和时间生长,对于冰草在沙地环境条件下生存和分布具有重要意义。本文研究了浑善达克沙地4-10月份土壤含水量变动情况和冰草种子萌发、出苗和幼苗生长对土壤含水量的响应。结果表明,4月下旬至5月上中旬的土壤含水量对冰草种子萌发、出苗和定居极为关键。控制条件下,冰草种子萌发的最适土壤含水量是12%-20%,出苗以及幼苗生长的最适土壤含水量是12%-16%。当土壤含水量低于3%,冰草种子不能萌发,土壤含水量低于6%时,幼苗不能出土和定居。当土壤含水量达到16%时,冰草幼苗生物量有所下降。在6%-8%的土壤含水量条件下,植株将更多的生物量投资于根的生长。 本文对浑善达克沙地低湿滩地、滩地-风沙沉积过渡区到风沙沉积区的赖草(Leymus secalinus (Georgi) Tzvel.)分株数、地上生物量、土壤水分和养分异质性进行了研究。结果表明,从低湿滩地、滩地-风沙沉积过渡区到风沙沉积区,随着土壤养分的降低,赖草分株数和地上生物量反而增加。赖草的分株数在三种生境中都存在空间自相关。并且,从低湿滩地、过渡区到风沙沉积区空间自相关的变程逐渐增加。地上生物量同样存在空间自相关,但变程以过渡区最大,风沙沉积区最低。土壤水分仅仅在风沙沉积区存在空间自相关。在三种生境条件下,土壤全氮和有机质的空间分布格局相似,都在低湿滩地和过渡区存在空间自相关且变程相似。在风沙沉积区不存在空间自相关。赖草的空间分布格局在低湿滩地为偏离随机适度聚集的分布格局,在过渡区近似于聚居分布,而在风沙沉积区为均匀分布格局。 豆科锦鸡儿属(Caragana )植物因其可以生物固氮而在草原生态系统当中具有特殊的地位。定量分析小叶锦鸡儿(Caragana microphylla )灌丛在浑善达克沙地不同生境条件下的分布格局,有助于理解植被与土壤养分循环之间的关系和合理制定退化沙地的恢复对策。本文采用地统计学中的半方差分析和分形分析两种方法研究了浑善达克沙地小叶锦鸡儿灌丛的空间分布格局,分析了不同生境中小叶锦鸡儿灌丛的植被、土壤水分和养分间的相关性。结果表明(1)小叶锦鸡儿灌丛在三种生境条件下(滩地、固定沙丘和半固定沙丘)的盖度、土壤有机质和全氮的空间分布符合球状模型,空间自相关显著;(2)土壤pH值在滩地和固定沙丘的空间分布符合球状模型且空间自相关显著,但在半固定沙丘空间自相关不显著;(3)土壤水分在三种生境中的空间分布都符合线性模型,空间自相关显著。(4)植被的变异尺度(变程)小于各个土壤要素的变异尺度。植被(小叶锦鸡儿灌丛)的分布和形成过程决定了土壤养分的分布和形成过程。当地的豆科植物在养分“沃岛”现象的形成中起了重要作用,合理的利用和布局当地的豆科植物,可以更加有效地补充草地生态系统的养分,从而有利于加快当地生态系统的恢复进程。

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We undertook geometric morphometric analysis of wing venation to assess this character's ability to distinguish Anopheles darlingi Root populations and to test the hypothesis that populations from coastal areas of the Brazilian Atlantic Forest differ from those of the interior Atlantic Forest, Cerrado, and the regions South and North of the Amazon River. Results suggest that populations from the coastal and interior Atlantic Forest are more similar to each other than to any of the other regional populations. Notably, the Cerrado population was more similar to that from north of the Amazon River than to that collected of south of the River. thus showing no correlation with geographical distances. We hypothesize that environmental and ecological factors may affect wing evolution in An. darlingi. Although it is premature to associate environmental and ecological determinants with wing features and evolution of the species, investigations on this field are promising. (C) 2012 Elsevier B.V. All rights reserved.

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The purpose of this paper is to investigate the occurrence and character of the vermiculite deposits approximately four miles northwest of Pony; Madison County, Montana. The deposits are situated in rolling foothills at the northern end of the Tobacco Root Mountains.

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Plant phylogenetic estimates are most likely to be reliable when congruent evidence is obtained independently from the mitochondrial, plastid, and nuclear genomes with all methods of analysis. Here, results are presented from separate and combined genomic analyses of new and previously published data, including six and nine genes (8,911 bp and 12,010 bp, respectively) for different subsets of taxa that suggest Amborella + Nymphaeales (water lilies) are the first-branching angiosperm lineage. Before and after tree-independent noise reduction, most individual genomic compartments and methods of analysis estimated the Amborella + Nymphaeales basal topology with high support. Previous phylogenetic estimates placing Amborella alone as the first extant angiosperm branch may have been misled because of a series of specific problems with paralogy, suboptimal outgroups, long-branch taxa, and method dependence. Ancestral character state reconstructions differ between the two topologies and affect inferences about the features of early angiosperms.

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Machine downtime, whether planned or unplanned, is intuitively costly to manufacturing organisations, but is often very difficult to quantify. The available literature showed that costing processes are rarely undertaken within manufacturing organisations. Where cost analyses have been undertaken, they generally have only valued a small proportion of the affected costs, leading to an overly conservative estimate. This thesis aimed to develop a cost of downtime model, with particular emphasis on the application of the model to Australia Post’s Flat Mail Optical Character Reader (FMOCR). The costing analysis determined a cost of downtime of $5,700,000 per annum, or an average cost of $138 per operational hour. The second section of this work focused on the use of the cost of downtime to objectively determine areas of opportunity for cost reduction on the FMOCR. This was the first time within Post that maintenance costs were considered along side of downtime for determining machine performance. Because of this, the results of the analysis revealed areas which have historically not been targeted for cost reduction. Further exploratory work was undertaken on the Flats Lift Module (FLM) and Auto Induction Station (AIS) Deceleration Belts through the comparison of the results against two additional FMOCR analysis programs. This research has demonstrated the development of a methodical and quantifiable cost of downtime for the FMOCR. This has been the first time that Post has endeavoured to examine the cost of downtime. It is also one of the very few methodologies for valuing downtime costs that has been proposed in literature. The work undertaken has also demonstrated how the cost of downtime can be incorporated into machine performance analysis with specific application to identifying high costs modules. The outcome of this report has both been the methodology for costing downtime, as well as a list of areas for cost reduction. In doing so, this thesis has outlined the two key deliverables presented at the outset of the research.

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Several approaches have been proposed to recognize handwritten Bengali characters using different curve fitting algorithms and curvature analysis. In this paper, a new algorithm (Curve-fitting Algorithm) to identify various strokes of a handwritten character is developed. The curve-fitting algorithm helps recognizing various strokes of different patterns (line, quadratic curve) precisely. This reduces the error elimination burden heavily. Implementation of this Modified Syntactic Method demonstrates significant improvement in the recognition of Bengali handwritten characters.

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This chapter reports on research work that aims to overcome some limitations of conventional community engagement for urban planning. Adaptive and human-centred design approaches that are well established in human-computer interaction (such as personas and design scenarios) as well as creative writing and dramatic character development methods (such as the Stanislavsky System and the Meisner Technique) are yet largely unexplored in the rather conservative and long-term design context of urban planning. Based on these approaches, we have been trialling a set of performance based workshop activities to gain insights into participants’ desires and requirements that may inform the future design of apartments and apartment buildings in inner city Brisbane. The focus of these workshops is to analyse the behaviour and lifestyle of apartment dwellers and generate residential personas that become boundary objects in the cross-disciplinary discussions of urban design and planning teams. Dramatisation and embodied interaction of use cases form part of the strategies we employed to engage participants and elicit community feedback.

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The accumulation and perpetuation of viral pathogens over generations of clonal propagation in crop species such as sweet potato, Ipomoea batatas,inevitably result in a reduction in crop yield and quality. This study was conducted at Bundaberg, Australia to compare the productivity of field-derived and pathogen-tested (PT)clones of 14 sweet potato cultivars and the yield benefits of using healthy planting materials. The field-derived clonal materials were exposed to the endemic viruses, while the PT clones were subjected to thermotherapy and meristem-tip culture to eliminate viral pathogens. The plants were indexed for viruses using nitrocellulose membrane-enzyme-linked immunosorbent assay and graft-inoculations onto Ipomoea setosa. A net benefit of 38% in storage root yield was realised from using PT materials in this study.Conversely, in a similar study previously conducted at Kerevat, Papua New Guinea (PNG), a net deficit of 36% was realised. This reinforced our finding that the response to pathogen testing was cultivar dependent and that the PNG cultivars in these studies generally exhibited increased tolerance to the endemic viruses present at the respective trial sites as manifested in their lack of response from the use of PT clones. They may be useful sources for future resistance breeding efforts. Nonetheless, the potential economic gain from using PT stocks necessitates the use of pathogen testing on virus-susceptible commercial cultivars.