典型黑土区村级尺度侵蚀沟演变

侵蚀沟的演变是东北水土流失过程的重要方面.利用1968和2009年亚米级遥感影像,获取典型黑土区村级尺度的侵蚀沟分布、耕地垄向和土地利用数据,基于1∶1万地形图获取等高线、坡度、坡长和垄向坡度数据,在地理信息系统和遥感技术的支持下,分析典型黑土区41 a村级尺度侵蚀沟的动态变化及其影响因素.结果表明:1)41 a间,典型黑土区侵蚀沟密度有明显增加的趋势,基于分辨率为亚米级遥感影像解译的侵蚀沟密度较以往研究结果大幅增加;2)自然坡度0.25°～1.5°范围内为该区域侵蚀沟密度变化最大的区域,8°以上区域由于实施退耕还林措施,侵蚀沟密度降低;3)300～500 m坡长区域侵蚀沟密度出现极值;4)由于实施改垄措施,41 a后垄向坡度在0～0.25°范围内耕地面积增加,大于0.25°范围内耕地面积均减少.     

中国跳小蜂科二新纪录种：膜翅目：跳小蜂科

本文报道了作者于１９９３－０４～０５间在安徽省采集的寄生蚧虫的跳中蜂２种，即日本羽盾跳小蜂Ｃａｅｎｏｈｏｍａｌｏｐｏｄａｓｈｉｋｏｋｕｅｎｓｉｓ（Ｔａｃｈｉｋａｗａ）和狭顶扁角跳小蜂ＡｎｉｃｅｔｕｓａｎｇｕｓｔｕｓＨａｙａｔ，皆为中国新纪录种，文中描述了它们的形态特征，记录了它们的寄生和分布。     

枣园不同寄主来源腐烂病菌分离株生物学差异性分析

以枣树和防护林腐烂病菌为研究对象,采用组织块分离法,柯赫氏法则验证后获得单菌落;将分离株置于不同营养条件和环境条件下,观察记录培养性状及差异;对标本制作徒手切片观察分生孢子器纵横切面,研究枣树和防护林腐烂病菌之间的生物学特性差异,以期为摸清枣树腐烂病菌来源奠定基础。结果表明:新疆阿克苏地区主要林木腐烂病菌株存在3个类群,即无气生菌丝羽毛状类群、少量轮纹状气生菌丝类群和少量放射状气生菌丝类群;最适分离株生长的温度为25~28℃,最适分离株生长的pH为4~5;光照条件对各分离株菌落生长有一定的促进作用;各分离株均可在大部分供试的碳源和氮源培养基上生长良好,说明分离株对营养的需求具有广泛性;分离株的分生孢子器纵横切面大小、耐高温性和对光照条件的适应性与寄主和地理来源有关;对酸碱的适应性与寄主来源有关,与地理来源无关。     

Mycological characteristics of the cultural layer of a medieval settlement on soddy calcareous soils

The difference between fungal communities in the cultural layer of a medieval settlement and in the background soddy calcareous soil is shown. In the cultural layer, the portion of spores, especially large spores (d > 6 μm), in the total fungal biomass is increased, whereas the portion of mycelium, especially with a thickness of > 4 μm, is decreased. The species composition of micromycetes in the cultural layer is also transformed; species from the Aspergillus and Fusarium genera predominate. The frequency and diversity of Penicillium representatives decreases, whereas the fungal species from the Phoma, Doratomyces, Geomyces, and Verticillium genera, which are not typical of the background soil horizons, increases. The diversity of the minor fungal species also increases in the cultural layer. An increased content of keratin-decomposing soil fungi is found in the cultural layer. It is argued that the use of the entire set of these characteristics makes it possible to perform mycological indication of the parts of the cultural layer that served different purposes (ancient streets, house floors, backing of the walls, etc.) within the settlement.     

The structure of fungal biomass and diversity of cultivated micromycetes in Antarctic soils (progress and Russkaya Stations)

The distribution of the fungal biomass and diversity of cultivated microscopic fungi in the profiles of some soils from East (Progress Station, valleys of the Larsemann Hills oasis) and West (Russkaya Station, the Marie Byrd Land) Antarctica regions were studied. The structure of the biomass (spore/mycelium and live cells/dead cells) was analyzed by fluorescence microscopy with staining using a set of coloring agents: calcofluor white, ethidium bromide, and fluorescein diacetate. The species composition of the cultivated microscopic fungi was determined on Czapek’s medium. The fungal biomass in the soils studied is not high (on the average, 0.3 mg/g of soil); the greatest biomass (0.6 mg/g) was found in the soil samples with plant residues. The fungal biomass is mainly (to 70%) represented by small (to 2.5 μm) spores. About half of the fungal biomass is composed of living cells. There are differences in the distribution of the fungal biomass within the profiles of different primitive soils. In the soil samples taken under mosses and lichens, the maximal biomass was registered in the top soil horizons. In the soils with the peat horizon under stone pavements, the greatest fungal biomass was registered in the subsurface horizons. Thirty-eight species of cultivated microscopic fungi were isolated from the soils studied. Species of the genus Penicillium and Phoma herbarum predominated.     

A comparative analysis of microbiomes in natural and anthropogenically disturbed soils of northwestern Kazakhstan

The goal of this study was to determine the relationships between the structure of the soil microbiome and the agroecological state of soils by the example of natural undisturbed (steppe areas) and anthropogenically disturbed (pastures, croplands, fallows) areas in the territory of northwestern Kazakhstan. The highest abundance of proteobacteria was found in the anthropogenically disturbed of fallows and in undisturbed soils; in other cases, actinobacteria and representatives of the Firmicutes phylum predominated. Different kinds of anthropogenic impacts resulted in the decrease in the portions of bacteria from the Acidobacteria, Gemmatimonadetes, and Firmicutes phyla. In the disturbed soils, the portions of bacteria from the Erysipelothrix, Mycobacterium, Methylibium, Skermanella, Ralstonia, Lactococcus, Bdellovibrio, Candidatus nitrososphaera, Catellatospora, Cellulomonas, Stenotrophomonas, and Steroidobacter genera increased. Bacteria of the Erysipelothrix and Methylibium genera occurred only in the undisturbed soils. The anthropogenically disturbed and undisturbed soils differed significantly in the taxonomic structure of their microbiomes forming two separate clusters, which confirms the efficiency of using the data on the structure of soil microbiomes when assessing the agroecological status of soils.     

中国跳小蜂科一新种三新记录种(膜翅目:跳小蜂科)

本文报道了分布于河南、山东、辽宁的4种跳小蜂,即短角细柄跳小蜂 Psilophrys brachycornisshi et wang,桑氏花角跳小蜂 Blastothrix kuwanai sugonjaev,细角刷盾跳小蜂 Cheiloneurus tenuicornis Ishii和铜绿花翅跳小蜂 Microterys chalcostomus(Dalman)。其中前一种是新种,后三种是我国新记录种。文中描述了它们的形态特征,记录了它们的寄主和分布。     

中国跳小蜂科昆虫区系初步分析

对中国目前已知的１３２种跳小蜂的区系进行了初步分析。结果表明，中国跳小蜂科昆虫在世界动物区系中的归属可分为１４个类型，其中以东洋区种类、古北区种类及东洋、古北二区共有种类较多，分别为４２种（３１．８２％），２８种（２１．２１％）和４１种（３１．０６％）。在中国动物区划中的归属共有２２个组合，其中以华南区种类（２６种，１９．７０％）、华中区种类（２４种，１８．１８％）和华北区种类（１９种，１４．３９％）较多。文章还列出了古北区跳小蜂种类在中国东部地区的分布南限和东洋区种类的分布北限。