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701.
控释肥膜壳对土壤酶活性及微生物量碳氮磷的影响 总被引:1,自引:0,他引:1
选用硫膜和树脂膜两种肥料膜壳,每种设置3个浓度梯度,研究了控释肥膜壳对土壤酶活性及微生物量碳氮磷的影响。结果表明,施用硫膜和树脂膜一定程度上对土壤生物学性质产生了影响。膜壳对土壤酶活性的影响主要表现在对脲酶和过氧化氢酶活性上,而对土壤磷酸酶活性影响不大。成熟期施用硫膜和树脂膜处理显著提高了土壤脲酶活性,这与结荚期有所不同,说明硫膜能提高花生成熟期土壤脲酶活性。树脂膜和硫膜处理均以中等量(2 g/kg)处理时微生物量碳和氮含量最大,施用控释肥残膜处理显著降低了微生物量磷含量。 相似文献
702.
报道采自四川卧龙的管巢蛛科管巢蛛属一新种,卧龙管巢蛛Clubiana wolongica sp.nov.。模式标本保存在河北师范大学生物学系。 相似文献
703.
《Journal of Natural History》2012,46(6):1461-1465
Chromosome numbers for 108 species of the genus Lotus (Leguminosae) are now known. This represents an increase of 32 new species which have been reported since a chromosome atlas for Lotus was published in 1965. At this rate, with just over one chromosome number being reported for a new species per year, it will require almost a century for the chromosome numbers to be determined for all of the species in the genus. A review of the cytogenetic features which have been observed in the genus through karyotype analyses, chromosome banding, Feulgen cytophotometry, anther culture, HCN reaction and interspecific hybridization is presented. These include cytomixis and B chromosomes (both found in hybrids of diploid species in the L. corniculatus group when L. alpinus was one of the parents), desynapsis, binucleate cell formation, polytene chromosomes in suspensor cells and trisomics in L. pedunculatus. There has been a reduction of HCN content in the species with evolutionary development which is correlated with basic chromosome number and geographic distribution. Classical karyotype analyses may not be a suitable method to investigate the parentage of L. corniculatus because of the chromosomal repatterning which has occurred during the evolutionary development of the closely related diploid species. 相似文献
704.
《Journal of Natural History》2012,46(17-18):1035-1087
The genus Helcystogramma Zeller from China is reviewed. Of the 20 species treated in this paper, nine are described as new: H. imagibicuneum sp. nov., H. flavifuscum sp. nov., H. brevinodium sp. nov., H. albilepidotum sp. nov., H. angustum sp. nov., H. flavistictum sp. nov., H. furvimaculare sp. nov., H. imagitrijunctum sp. nov. and H. rectangulum sp. nov.; six are newly recorded for this country: H. flavilineolella Ponomarenko, H. bicuneum (Meyrick), H. epicentra (Meyrick), H. perelegans (Omelko et Omelko), H. fuscomarginatum Ueda and H. lutatella (Herrich-Schäffer); the previously unknown females of H. epicentra (Meyrick) and H. hassenzanensis Park et Hodges are described for the first time; H. bicuneum (Meyrick) and H. epicentra (Meyrick) are redescribed; and the misidentification of H. trijunctum (Meyrick) is clarified. These species are arranged into five species groups based on the forewing patterns and the genital characters: the flavilineolella group, the hibisci group, the perelegans group, the triannulella group and the trijunctum group. Images of the adults and the illustrations of the male and female genitalia are provided. A key to distinguish the Chinese species and three maps to show the localities of these species are included. 相似文献
705.
《Journal of Natural History》2012,46(15):1077-1100
Calanoid copepod specimens attributable to Lucicutia grandis (Giesbrecht, ), L. bradyana Cleve, , L. wolfendeni Sewell, , and L. rara Hulsemann, ) were studied from antarctic and subantarctic waters collected during RV Eltanin crusies 4–11 and 23, and RV Ob cruises 1 and 3. In addition, identified specimens from the Pacific and Indian Oceans deposited in the systematic collections of the National Museum of Natural History, Smithsonian Institution (Washington, DC, USA) and the Zoological Institute, Russian Academy of Sciences (St Petersburg) were also examined. Both sexes of a new species are described from the eastern tropical Pacific Ocean, L. hulsemannae. Lucicutia hulsemannae is distinguished from L. grandis, L. bradyana and L. wolfendeni by the morphology of the rostrum, genital complex, including plug, and leg 5 of both sexes. Lucicutia bradyana is not found outside the Southern Hemisphere but L. grandis is recorded from the Arabian Sea, the Bay of Bengal, tropical Indian Ocean, as well as its type locality in the eastern tropical Pacific Ocean. Lucicutia wolfendeni is found in all oceans except the Arctic Ocean. The status of L. bradyana, previously rejected as a separate species by Hulsemann (), is restored. Lucitutia rara is considered a junior synonym of L. bradyana. 相似文献
706.
《Journal of Natural History》2012,46(27-28):1745-1758
This study characterizes the ecology, behaviour and morphology of populations of Abrocoma schistacea and A. uspallata in north-western Argentina. We carried out live-trapping, tagging and recapture during 2006–2008. Burrow structure and vegetation were described. Diet composition and the activity of chinchilla rats were defined. Both species inhabit rock crevices in the pre-Andean foothills of the Monte Desert. Some of their morphological specializations for saxicolous life, such as foot pads for better traction on rocky surfaces and reduced nails, are convergent with those of other saxicolous species. Both species appear to be diurnal, with activity peaking in the early morning. Dietary analyses suggest trophic specialization by both species. Density of A. schistacea was of 0.15 ± 0.06 individuals ha?1; with individuals living in groups of 3–4 animals. Given their low abundance, restricted distribution and high level of habitat and food specialization, we urge that populations of this species be protected through effective management. 相似文献
707.
《Journal of Natural History》2012,46(6):1347-1380
In the present revision 15 species of Littorophiloscia are recognized. Six species, namely L. tropicalis, L. koreana, L. amphindica, L. pallida, L. bifasciata and L. hawaiiensis are described as new. Littorophiloscia isabellae (Vandel, 1973) is considered to be a junior synonym of L. albicincta (Vandel, 1973), and Philoscia dartevellei Brian, 1953 and Vandeloscia orientalis Roman, 1977 are considered to be junior synonyms of L. culebrae (Moore, 1901). Alloniscus compar sens. Vandel, 1952 nec Budde-Lund, 1893 is considered to be distinct from L. riedli (Strouhal, 1966) and it has been renamed L. tropicalis sp. nov. The genera Bilawrencia Vandel, 1973, Helenoscia Vandel, 1977, Vandeloscia roman, 1977 and Sayoscia Schultz, 1983 are considered to be synonymous with Littorophiloscia. Diagnostic characters of all the species are illustrated. A map and comments on the distribution of the 15 species are included. 相似文献
708.
《Journal of Natural History》2012,46(33-34):2243-2256
The Indonesian island Sulawesi is well known for its fascinating fauna. Among the atyid and palaemonid freshwater shrimps described from Sulawesi are also a number of endemic species. In contrast, freshwater shrimps have never been reported from the nearby and smaller Peleng Island. Here we describe Caridina thomasi sp. nov. as a first record of an atyid freshwater shrimp from Peleng and compare it with atyids from Sulawesi and other localities. The new species is probably endemic to the island and shows some characters never described in the genus Caridina before. However, a molecular phylogeny of atyid shrimps from the Indo‐West Pacific based on mitochondrial DNA (16S) places C. thomasi within a clade of typical species of Caridina. We tentatively assign the new species to the genus Caridina and discuss the possibility of future changes in the classification of species in this genus. 相似文献
709.
哈斯巴特尔 《内蒙古民族大学学报(自然科学版)》2008,23(3):301-305
本研究通过对内蒙古典型草原区科尔沁沙地北缘的巴林左旗查干哈达苏木不同类型(流动、半流动)的沙地进行植物种类年度变化规律研究,阐明飞播对不同沙地原生植被植物种类的作用,并在飞播区和对照区比较研究的基础上,剖析了植物种类的动态变化、相关植物种的侵入和消减过程. 相似文献
710.