Cartographic Procedure for the Analysis of Aeolian Erosion Hazard in Natural Parks (Central System,Spain)

Cartographic analysis of the hazard of erosion is a useful tool for the planning and management of natural parks, helping to establish measures for protection and correction. Such parks, which offer spectacular landscape views and natural beauty, must be conserved with all their resources. Accordingly, park managers must have the cartographic tools for hazard planning, which is necessary for the rational and sustainable handling of human activities and the establishment of preventive and corrective measures. The present work describes a cartographic procedure using GIS that determines the risk of aeolian erosion. The method was applied to two protected natural parks in the central mountain system in Spain. This cartographic method revealed a weak risk of hazard of erosion in low‐lying areas or valley floors, with increasing risk in areas of deflation. These areas were explored by mapping geomorphological domains and slopes, characterising different surficial deposits: colluvium, piedmonts, debris cone, alluvial fans and river terraces. Aeolian erosion on cultivated surfaces with gentle slopes was observed to be low, but in sectors with little agricultural activity and undulated reliefs, the hazard of erosion is important owing to the high analytical and textural erodibility and scant vegetation cover of these sectors. These parameters were studied on the basis of the mapping of soils and soil profiles. Additionally, the cartography of vegetation and the wind index in the cartographic procedure allowed for the different degrees of aeolian erosion to be better quantified. Copyright © 2012 John Wiley & Sons, Ltd.     

黄壤旱坡地退耕还林还草对减少土壤磷流失的作用

在贵州中部黄壤旱坡地上 ,通过无界径流小区以及野外坡面径流小区试验 ,对退耕还林还草初期阶段旱坡地地表径流中水溶态磷和颗粒态磷流失量的变化进行了研究。结果表明 :退耕还林还草后黄壤旱坡地地表径流中颗粒态磷含量比相应的旱地减少 2 2 .17%～ 6 3.4 8% ,而水溶态磷含量也减少 3.0 3%～ 4 4 .2 9% ;退耕还林区土壤水溶态磷和颗粒态磷的流失量分别比玉米种植区减少 38.6 5 %和 35 .0 8% ,退耕还草区土壤水溶态磷和颗粒态磷的流失量分别比玉米种植区减少 5 3.4 2 %和 4 1.94 %。退耕还林还草一方面减少了肥料的施用量 ,另一方面能明显减少土壤磷的流失量 ,特别是水溶态磷的流失 ,退耕还林还草工程是减少土壤磷流失和控制非点源污染的有效途径。     

Diversity and dynamics of eco-units in the biological reserves of the Fontainebleau Forest (France): Contribution of soil biology to a functional approach

Beech integral biological reserves of the Fontainebleau forest (France) display varied site conditions due to geomorphological heterogeneity and to interactions between biological components of the ecosystem. Taking examples in shifts observed in plant communities following gap opening, the authors show that, as Oldeman viewed it, tree-fall gaps seem to be the driving force in sylvigenesis as well as a source of spatial biodiversity. Studies carried out on macromorphological features of humus profiles and on the behaviour of soil invertebrate communities (Lumbricidae and Nematoda) pointed out two key aspects of forest functioning. First, the renewal of the forest ecosystem is linked to the dynamics of humus forms and of soil animal functional groups, featuring the regeneration of trees. Second, tree-fall gaps are places where the forest ecosystem is destabilized and thereafter may renew itself or on the contrary may evolve towards another ecosystem, showing either a co-adaptation between the sylvigenetic and the edaphic cycle, or a discordance between these two cycles. These two aspects (co-adaptation and discordance), important from the point of view of fundamental ecology and forest management, suggest a need for further field research.

Résumé

La hêtraie des réserves biologiques intégrales de la forêt de Fontainebleau offre des situations naturelles variées en fonction de l'hétérogénéité géomorphologique et des interactions entre les composantes biologiques de l'écosystème. Prenant comme exemple l'évolution des associations végétales au sein des clairières, les auteurs montrent que, selon la conception d'Oldeman, le chablis apparaît comme l'élément moteur de la sylvigénèse et un facteur important de biodiversit é spatiale. Des études portant sur la caractérisation macromorphologique des profils d'humus et le comportement des peuplements d 'invertébrés du sol (Lumbricidae, Nematoda) mettent en avant deux points importants pour le fonctionnement de l'écosysteme forestier. Premièrement, le renouvellement de l'écosystème est associé à la dynamique des humus et des groupes fonctionnels de la pédofaune, façonnant ainsi la niche de régénération. Deuxièmement, les clairières apparaissent comme une zone de rupture de l'écosystème forestier pouvant lui permettre, soit de se renouveler, soit d'évoluer vers un autre écosystème, montrant ainsi soit une co-adaptation entre le cycle sylvigénétique et le cycle édaphique, soit une discordance entre ces deux cycles. Cette approche fonctionnelle par le biais de la biologie des sols suggère une réflexion touchant autant l'écologie fondamentale que la gestion forestière.     

马铃薯晚疫病菌基因文库的构建

用酶一氯化苄法制备高分子量晚疫病菌总ＤＮＡ,通过Ｓａｕ３Ａ部分酶切并纯化后得到１５－２５ｋｂ的酶切片段,并以具有广寄主范围的柯斯质粒ＰＬＡ２９１７为载体,用Ｔ４ＤＮＡ连接酶连成为重组ＤＮＡ,包装到入噬菌体颗粒中,转染受体菌Ｅ．ｃｏｌｉＳ１７－１。利用四环素和卡那霉素抗性来筛选鉴定重组子,得到１０６５６个重组子,这些重组子群即为晚疫病菌的基因组文库。     

Management of sea cucumber stocks: patterns of vulnerability and recovery of sea cucumber stocks impacted by fishing

Identifying rates of change in the abundance of sea cucumbers under differing management regimes is fundamental to estimating commercial yields, identifying ecological interactions and facilitating management. Here, we review the status of sea cucumber stocks from a range of Pacific Island countries (Samoa, Tonga, Palau, Fiji and Papua New Guinea), some of which have had a moratorium on exports for up to a decade. We use a time‐series approach to look at variation in sea cucumber presence, coverage and density from survey and re‐survey data. Results give an appreciation of variation between ‘high’ status (less impacted) and depleted stocks. Survey data show marked declines in coverage and abundance as a result of artisanal fishing activity, and although species groups were not lost at a country level, local extirpation and range restriction was noted. Resilience and ‘recovery’ following cessation of fishing varied greatly, both among locations and among the species targeted. Worryingly, even after extended periods of moratorium, the density of some species was markedly low. In many cases, the densities were too low for commercial fishing, and may be at a level where the effective population size is constrained due to ‘Allee’ affects. From these results, we suggest that management regimes presently employed are generally not well aligned with the level of response to fishing mortality that can be expected from sea cucumber stocks. New adaptive, precautionary approaches to management are suggested, which would allow more timely interventions to be made, while refined information on stock dynamics is sought.     

Comparison of methods for routine separation of coagulase-negative staphylococci from micrococci isolated from sheep

A total of 176 Gram-positive, catalase positive cocci strains, isolated from sheep were studied by different routine tests for the differentiation of staphylococci and micrococci, comparing their validity and usefulness. By glucose fermentation and growth in the anaerobic portion of thioglycolate 85 and 73.6% respectively of coagulase negative staphylococci were misclassified as Micrococcus spp. Susceptibility to lysostaphin was an adequate test for the differentiation of the strains. Atypical results in the production of acid from glycerol/erythromycin were obtained in 11.8% of the coagulase negative strains and 16.7% of micrococci. The combined use of the selective media furazolidone agar and Schleifer and Krämer medium resulted in a fast and useful separation of ovine staphylococci and micrococci. The bacteriolytic activity misclassified 32.2% of the coagulase negative strains.     

Therapeutic effect of anti-TNF-α antibody and levofloxacin (LVFX) in a mouse model of enterohemorrhagic Escherichia coli O157 infection

The ability of an anti-TNF-α antibody to confer protection against enterohaemorrhagic Escherichia coli (EHEC) O157 was investigated in germfree IQI mice. The use of an antibiotic levofloxacin (LVFX) alone or with the antibody was also studied. Protection included an increase in survival rate. Treatment with the anti-TNF-α antibody inhibited the histological signs associated with EHEC infection but did not prevent the colonization of EHEC or production of Shiga toxin (Stx). No clinical signs were observed and EHEC was completely eliminated in the mouse model receiving both anti-TNF-α antibody and LVFX. Anti-TNF-α antibody suppressed inflammatory cytokine response in the mouse kidney and brain by EHEC infection.     

Fatal septicaemia caused by Aeromonas hydrophila in a patient with cirrhosis

In this case report from Italy we describe a fatal infection caused by A. hydrophila in a 39 yr old cirrhotic patient. This pathogen was isolated as a pure single culture from the patient's blood sample. The patient died on the second day of hospitalization from overwhelming sepsis. The A. hydrophila isolate was tested for different potential virulence properties, such as invasiveness, adherence, exotoxins production, presence of fimbriae and for the patterns of resistance to a variety of antimicrobial agents. Although, the Aeromonas species are infrequently reported as a cause of human infections, the present case study confirms the capability of these pathogens to induce serious human infections.     

Cytochrome P-450 in insects. 7. Age dependency and phenobarbital induction of cytochrome P-450, P-450 reductase,and monooxygenase activities in the black blow fly (Phormia regina,Meigen)

Development and phenobarbital (PB) induction of microsomal cytochrome P-450, NADPH-cytochrome c (P-450) reductase, two epoxidation, and two O-demethylation activities were examined in chronologically timed populations of female black blow flies (Phormia regina, Meigen). Measurements of these enzymes started with the pharate adult stage and ended 5 days following eclosion. Induction occurred in all enzymes, even at 0.005% PB, and was maximum at 0.15%. Dramatic induction of the O-demethylation of 7-methoxy-4-methylcoumarin was observed in flies dosed with the maximum concentration of the drug. This monooxygenase activity increased to nearly 1400 times the level in control flies, whereas the other O-demethylation (methoxyresorufin) and the two epoxidation reactions exhibited considerably less change. Induction of the structural enzymes of this enzyme system were 10-fold for cytochrome P-450 and 5-fold for NADPH-cytochrome c (P-450) reductase. These data suggest that PB induces several P-450's in the blow fly, particularly one bearing a high degree of specificity for 7-methoxy-4-methycoumarin.     

德摩根商拓扑代数的拓扑性质

探讨了德摩根商拓扑代数的连通性，可分性等一些拓扑性质，并建立了德摩根商拓扑代数为Ｔ１的一个充分必要条件。