塔里木沙漠石油公路选线技术研究

在世界上第二大流动沙漠－塔克拉玛干沙漠中，修筑长５００余ｋｍ的塔里木沙漠公路，其难度之在，当属世界前列。本文训这一工程实施中，适用的沙漠公路选线技术进行了系统研究，其中，沙漠公路布设原则的研究及选定；沙漠公路的几何特征与沙害对应关系的研究，沙漠公路的测设技术及主要技术指标的选定以及从地貌方面研究的沙漠公路防护等，都为沙漠公路的成功修筑提供了保证。     

北非撒哈拉沙漠腹地地理环境特征--与塔克拉玛干沙漠对比

北非撒哈拉是世界第一大沙漠 ,中国的塔克拉玛干沙漠为世界第二大流动沙漠。撒哈拉是非洲语“大荒漠”之意 ,面积 8× 10 6km2 ,囊括了北非的大部分国家和 85 %以上的面积 ,除南部几内亚湾和北部地中海边的小面积地带外 ,其地理座标约处于 10°～ 35°N ,和 17°33’W～ 4 0°E之间。塔克拉玛干沙漠维吾尔语“进去出不来”之意 ,面积约 3.4× 10 5km2 ,约在 37°～ 4 1°N ,78°～ 88°E之间。     

塔克拉玛干沙漠肖塘地区1995年气候及其影响评价

本文通过对１９９５年１￣１２月塔克拉玛干沙漠肖塘气象观测站资料统计，分析结果肖塘年降水汨００．２ｍｍ，年平均气温１１．１℃，极端最高气温４２．８℃，出现炎热高温天气４９天，沙尘暴天气５３天，年平均风速２．６ｍ／ｓ，最大风速１９．０ｍ／ｓ，盛行ＮＥ风。与同期北缘山前绿洲轮台的资料对比，表明沙漠冬季“冷湖”和夏季“热锅”效应显著，绿洲降水多于沙漠，沙漠蒸发多于绿洲。最后针对塔里木油气开发建设给出当年度     

巴丹吉林沙漠第四纪研究评述与讨论

近20年来巴丹吉林沙漠第四纪研究倍受地学界的关注,取得了较大的进展,但在一些主要问题的认识和结论上,分歧和争论极大。在综合分析大量研究成果的基础上,对第四纪研究进行了系统的评述和讨论,指出了这些研究中存在的问题、以及出现分歧和相互矛盾的原因。在沙漠形成的时代上,现有的研究主要是对沙漠部分地区的地层断代和沙丘浅部的测年,尚没有系统的工作,为此这里特别对影响沙漠时代研究的几个主要因素进行了详细的讨论。关于高大沙山和其间湖泊的形成机制,前者有多因素理论和地下水理论,后者有沙山间负地形理论说和断裂构造理论。尽管这些理论的依据和手段主要是运用不同的地球化学元素来示踪水源,但得出的结论迥异。通过对这些结果的分析,认为彼此的适用性还需进一步的证实。湖泊水源争论的原因主要是缺乏对沙漠地貌、下部地质、沙山钙结层和植物根套的综合研究所致,沙漠下部地质的进一步研究是解决这些问题的关键。在沙漠气候及其演化的研究上,西风环流和东亚季风对沙漠的形成和演化的影响程度还不清楚。最后对巴丹吉林沙漠的未来研究进行了展望。     

塔克拉玛干沙漠及其周缘地区的研究新进展

1 引言浩瀚而荒芜的塔克拉玛干沙漠,面积337600平方公里,是中国最大的沙漠和世界第二大流动沙漠(仅次于阿拉伯半岛的鲁卜哈利沙漠)。它位于大陆腹地,具有极端干燥的环境,著名的探险家斯文·赫定曾称之为“死亡之海”,其当地名称“塔克拉玛干”被释为“进去出不来”。因此,长期以来,人们对它所知甚少,甚至充满了神秘。     

塔克拉玛干沙漠地表感热特征分析

利用1979年3月~2004年2月月平均的NCEP/DOE新再分析地表感热资料,在分析塔克拉玛干沙漠四季感热基本气候特征的基础上,通过EOF分析方法,对沙漠地表感热异常变化的空间结构和时间演变趋势作了诊断研究。结果表明:1)沙漠地区地表感热通量的分布存在较大的季节和区域性差异。2)根据各季地表感热距平场的EOF分析,该区感热异常主要有全区一致型、南北差异型以及西北~东南差异型三种常见的分布模态;3)近25年来,塔克拉玛干沙漠春季和夏季地表感热在第一空间尺度上总体变化趋势平缓,秋季在波动中有明显增强的趋势;在第二空间尺度上夏季和秋季变化趋势不太显著,而春季在沙漠北部有减弱的趋势,南部有增强的趋势。     

沙漠腹地-荒漠戈壁-绿洲的气候过渡性研究

利用塔里木盆地塔中气象站、肖塘气象站和轮台气象站1999-2003年的资料,通过对比分析,研究沙漠腹地-荒漠戈壁-绿洲的气候过渡性规律。结果表明,由于地理位置和下垫面的不同,从沙漠腹地-荒漠戈壁-绿洲,气候存在过渡性差异。     

库布齐沙漠水沙景观的历史演变

库布齐沙漠位于鄂尔多斯高原北部,东西走向呈带状横于黄河南岸,"十大孔兑"由北向南贯穿沙漠汇入黄河,形成风水交互的水沙格局。结合前人研究成果、古籍、遥感影像等资料,梳理并探讨库布齐沙漠水沙景观的演变历史及形成原因。研究认为库布齐沙漠发育过程可分为两大阶段:古沙漠阶段和现代沙漠阶段,现代沙漠发育于全新世,末次冰消期气温回暖,使得古沙漠固定并消亡,古沙漠主要源自于地质作用和气候波动,而现代沙漠则是人为和自然的共同作用;"十大孔兑"发育在更新世早-中期,全面形成于更新世晚期,主要受到新构造运动及区域气候因素的影响开始发育并切割鄂尔多斯高原北部。同时研究指出,"流水占主导"的风水交互模式是现代库布齐沙漠水沙格局的主要成因。     

大青沟自然保护区大型真菌对沙地环境的适应与气候条件的相关性

大青沟自然保护区与其周边地区相比具有极其丰富的种类多样性，生境异质性较丰富，具木生、土生、粪生、虫生和菌根菌等5种类型，以木生和土生为主；真菌对沙地环境的适应性强，表现在子实体小型化，浅色种类居多，草原沙漠特有种类占一定比例；5至10月真菌大量发生，其中以8、9月份的种类最多，与其上一个月份的气温和降水量有密切的关系，并出现‘滞后现象’；自然干扰和人为干扰共同影响着大青沟的生态环境，前者以风蚀，干旱、沙为为主，后者以旅游，砍采、放牧、耕种为主，适度干扰可增加物种多样性；应注意真菌的就地保育。     

古尔班通古特沙漠南缘增温效应研究

利用2年沙漠边缘至绿洲4个观测点的气象资料,计算得到感热通量、湍流热量、净辐射、同一高度的气压等,讨论这些要素的时间和空间变化规律,解释绿洲至沙漠气温逐渐增加的原因,以对沙漠增温效应做出进一步的分析,为发挥特定地区的农业气候资源优势,促进农业结构调整和区域经济发展及构建新型农业技术体系提供理论基础.     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

Characterization of Sclerotinia minor populations in Texas peanut fields

In the summer of 2004 an epidemic of sclerotinia blight of peanut, a disease caused by Sclerotinia minor, occurred in Texas in fields where the disease was never previously detected. The disease was observed on many plants within one of the fields (>3000 disease foci), although most foci were <1 m. It is hypothesized that these observations were inconsistent with the recent introduction of a monocyclic pathogen, even if disease developed under conducive environmental conditions. The pattern of disease is most suggestive of the presence of foliar (ascospore) infections, although air temperature was above the known limits for apothecia development if the pathogen had arrived in the field in 2004 peanut seed. To further examine this epidemic, 232 isolates were collected, across a variety of spatial scales spanning this field and other Texas peanut fields, and evaluated for aggressiveness, fungicide sensitivity and genotypic diversity. There was wide variation among isolates for the phenotypic characteristics measured, but there was no evidence that a genotypically unique, highly aggressive, and fungicide resistant isolate had been introduced or evolved. The predominant genotype, TX1, which contained 154 isolates, was found in every county and field population.     

Eyespot of Cereals Revisited: ITS phylogeny Reveals New Species Relationships

Four species so far classified in Pseudocercosporella or Ramulispora (hyphomycetes) are associated with eyespot disease symptoms of cereals. Two of these have been linked to teleomorphs that were described in Tapesia. Sequence data derived from the Internal Transcribed Spacer region (ITS1, 5.8S and ITS2) of the rDNA operon showed, however, that the eyespot fungi associated with Tapesia are not congeneric with Ramulispora sorghi, the type of Ramulispora. The genus name Tapesia is now rejected in favour of the conserved name Mollisia, which appears to comprise heterogeneous fungi. Tapesia yallundae is not closely related to the type of Mollisia, M. cinerea, but clusters separately, being more closely allied to species with Cadophora anamorphs. A new holomorph genus, Oculimacula, is therefore proposed for teleomorphs of the eyespot fungi, while the anamorphs are accommodated in Helgardia gen. nov.     

Tumours of Begonia and some other ornamentals,induced by Corynebacterium fascians

In 1975 many tumours were observed in plants ofBegonia Schwabenland grown in Aalsmeer. Submersion of the roots ofNicotiana megalosiphon seedlings in a homogenate of tumorous tissue, induced tumours after two weeks. Short periods of submergence yielded results similar to those obtained after longer periods. Tumour homogenates lost their infectivity after ten min at 50°C. Aphids transmitted the infectious agent.Treatment with propylene oxide did not inhibit infectivity completely. Filtration through a 450 nm filter removed the infectious agent.Tobacco tumor virus or a viroid could not be isolated. Cultures ofCorynebacterium fascians, isolated from tumours ofN. megalosiphon were highly infectious and induced tumours in healthyN. megalosiphon andBegonia. Tumorous tissue homogenates ofPelargonium zonale, Dahlia sp.,Gladiolus sp., andLilium sp. also caused tumours inN. megalosiphon, from whichC. fascians was isolated. It was not possible to produce tumours inN. megalosiphon with homogenates from roses with symptoms of bud proliferation.Samenvatting In 1975 werden vele tumoren waargenomen inBegonia Schwabenland op Aalsmeerse bedrijven (Fig. 1). De infectiositeit van tumorweefsel kon goed en snel worden vastgesteld door de wortels van zaailingen vanNicotiana megalosiphon in een homogenaat van tumorweefsel te dompelen. Tumoren ontstonden na twee weken, de eindbeoordeling geschiedde na een maand (Fig. 2). Ook verschillende andereNicotiana spp.,Melilotus officinalis (Fig. 3) enPisum odoratum (Fig. 4) werden aangetast.Bij de infectiositeitstoets gaven zeer korte dompeltijden even goede resultaten als langere (Tabel 1). Infectieus sap verloor zijn infectievermogen na 10 min verhitting bij 50°C. Bladluizen brachten de smetstof over. Propyleenoxide verminderde de infectiositeit wel, doch onderdrukte deze niet totaal. Bij filtratie door een 450 nm filter bleef het infectieuse agens op het filter achter. Het tumor-inducerende agens was ook aanwezig in die delen van planten met tumoren welke gezond leken en het ging voor een gering deel over met zaad (Tabel 2).Uit tumoren konden wij geen tabakstumorvirus of een viroïde isoleren. Culturen vanCorynebacterium fascians, geïsoleerd uit tumoren vanN. megalosiphon bleken zeer infectieus en veroorzaakten tumoren inN. megalosiphon enBegonia. Homogenaten van tumorweefsel vanPelargonium zonale, dahlia (Fig. 5), gladiool (Fig. 6) enLilium Mid Century Hybrid Enchantment (Fig. 7) veroorzaakten ook tumoren opN. megalosiphon, waaruitC. fascians werd geïsoleerd. Met sap van kroeskopzieke rozen konden wijN. megalosiphon niet besmetten.