Search

Authors acknowledge funding from the European Union's Horizon 2020 research and innovation program under Grant 642018 (GREEN‐WIN project) and funding from the project INSeaPTION as part of ERA4CS, an ERA‐NET initiated by JPI Climate, and funded by BMBF (DE), MINECO (ES), NWO (NL), and ANR (FR) with co-funding by the European Union (Grant 690462). Coastal flood risk reduction (CFRR) presents a significant public funding challenge, due to its high upfront costs and long-term benefits, and this challenge will increase with future sea-level rise. The funding challenge necessarily involves multiple levels of government, due to the regional nature of CFRR public goods involved. Yet there has been little research comparing such multilevel arrangements across countries, and in particular exploring the performance of public funding arrangements for providing coastal flood risk reduction. We address this gap, applying fiscal federalism to develop a multilevel governance analysis of public decision-making and fiscal authorities for CFRR in the Netherlands, Germany, the UK and Australia. For each country, we locate key decision-making and fiscal authorities in multilevel governance arrangements, and analyse their alignment with the benefits of CFRR measures (spillovers). We find diverse coastal flood risk governance arrangements ranging from highly centralised (NL), mixed arrangements, involving regional centralisation (Germany) or partial devolvement (UK), to full decentralisation (AUS). Further, we find that in accordance with fiscal federalism, multilevel coastal flood risk governance arrangements are generally reflective of the distribution of the benefits across different levels of government, with some exceptions (Germany and UK). Finally, exploring the outlook of current arrangements under sea-level rise, we find that major fiscal redistributions may be put under pressure by rising costs likely under SLR and future coastal development. This is particularly the case for those systems which operate under hazard-based, as opposed to risk-based, coastal protection policies. Further, we find that both fully and moderately decentralised arrangements may require greater central support for alternative measures, such as retreat, in light of growing financial burdens on local governments. Postprint

Unidad de excelencia María de Maeztu MdM-2015-0552 Appropriate institutions are essential for climate change adaptation. Yet diverse approaches to institutional analysis are available, encompassing different ontological and epistemological assumptions, and thus yielding insights on very different aspects of institutions in adaptation. Therefore, efforts to expand knowledge in this domain can be usefully informed by an assessment of approaches to institutional analysis in the adaptation literature, which is to date lacking. We address this gap by conducting a systematic review of the adaptation literature addressing institutions. Our review characterises approaches to institutional analysis by identifying methodological choices and the philosophy of science underpinning them. We then analyze the distribution of approaches to institutional analysis across different adaptation situations, contextualizing our results within methodological debates in adaptation research regarding the appropriateness of positivist, interpretative, or post-normal approaches. We find that institutional analysis of adaptation is now engaging with 'how' and 'why' questions, beyond descriptive questions that characterise the adaptation 'barriers' literature, that diverse philosophies of science drive methodological choice, and that post-normal approaches, e.g. co-design approaches, hardly address institutions. We conclude that support for interpretative approaches, and for institutional analysis in post-normal approaches is needed. The latter is important for adaptation planning processes in developing countries under the UNFCCC.

Resume Une famille revenue d'un voyage au Salvador a presente des troubles digestifs (douleurs abdominales, diarrhees). L'examen parasitologique des selles a revele la presence d'oocystes de Cyclospora cayetanensis, qui ont disparu sous trimethoprime-sulfamethoxazole. Ce parasiter est un protozoaire, de l'ordre des coccidies, connu chez l'homme depuis 1877. Il est cosmopolite mais plus frequent en zone tropicale, avec une prevalence de 2 a 11% selon les pays. L'infestation, due a l'ingestion des parasites avec l'eau et les crudites contaminees, provoque des troubles digestifs varies, plus importants chez le sujet immunodeprime (amaigrissement, deshydratation). Le diagnostic est base sur l'examen parasitologique des selles. Le traitement par trimethoprime--sulfamethoxazole est efficace. La prophylaxie necessite le respect des regles de l'hygiene alimentaire.

Institutional fit is operationalized by transferring transaction costs economics (TCE) to the analysis of instances of social-ecological interdependence. We carefully spell out the differences with conventional TCE and outline analytical steps based on discriminating alignment that enable a TCE analysis of environmental governance of “nature-related transactions”. We illustrate the approach through the example of wildlife management in Germany. Here we find hierarchical governance (a prohibition) of killing of wolves embedded into a polycentric hybrid monitoring arrangement. In applying TCE to nature-related transactions, we argue that characteristics of nature-related transactions can be subsumed under the core categories of jointness, uncertainty, asset specificity, frequency, rivalry, excludability and social-relational distance. Benefits of this approach include its generating a narrow list of descriptors of instances of biophysically mediated interdependence related to one evaluation criterion: cost-effectiveness. The TCE of nature-related transactions thus identifies sets of stylized contextual factors and aspects related to the governance of hazards of ex-post opportunistic behavior that cut across scales. They can be used as composite descriptors that facilitate analysis of complex multi-scalar arrangements of natural resource governance. We propose the concept of ‘governance challenge’, derived from TCE, as being useful for building research on environmental governance.

Resume La balantidiose, zoonose parasitaire due a un protozoaire cilie, est cosmopolite, mais se rencontre surtout dans les pays tropicaux et subtropicaux. Elle se transmet a l’homme par ingestion d’eau ou d’aliments souilles contenant des kystes provenant des excrements des porcs. Comme les animaux, le sujet infeste reste le plus souvent porteur asymptomatique. Dans le cas contraire, les troubles cliniques peuvent preter a confusion avec une amoebose intestinale. Les complications graves sont rares mais parfois mortelles. Le diagnostic biologique est facile par l’examen parasitologique des selles. Le traitement, a base de tetracyclines ou de nitro-imidazoles, est tres efficace.

Resume Les cestodes sont des vers plats tres repandus dans le monde. Ils ont un corps tres long, ou strobile, forme de nombreux anneaux qui contiennent des organes mâles et femelles. Ils sont situes dans l’intestin de l’homme provoquant des troubles digestifs. Les hotes intermediaires varient selon le taenia. Le diagnostic est affirme par la mise en evidence des anneaux ou des œufs a l’examen parasitologique des selles. Le praziquantel est efficace en cure courte.

Resume La fievre jaune est une hepatonephrite aigue due a un flavivirus (virus amaril), transmis par des moustiques (Aedes et Haemagogus). Cette arbovirose tropicale sevit en Afrique intertropicale et dans le bassin de l’Amazonie. Le reservoir de virus est le singe. Apres quelques jours d’incubation, l’evolution est rapide avec une fievre elevee, des cephalees, un ictere cutaneo-muqueux et des hemorragies. Les constantes hepatiques sont tres perturbees et le deces survient en quelques jours. La confirmation par la biopsie de foie (corps de Councilman) est trop souvent tardive, post-mortem. A defaut de traitement, la prophylaxie repose sur un vaccin efficace pendant de longues annees.

In many cases in which climate change affects natural resources, impacts are uncertain and adaptation to climate change often involves collective action problems at the local level, which are embedded in multilevel governance regimes. Adaptive management (AM) is an emerging approach to deal with such uncertainty and complexity by promoting multilevel institutions that are robust to change and able to learn. Much of the literature evaluating AM in multilevel governance regimes, however, focuses only on the adherence to certain structural features said to make AM successful, leaving aside the question whether AM actually produces desired outcomes. This paper evaluates AM in multilevel regimes also in terms of the outcomes they produce. To this end, we first apply the Management and Transition Framework (MTF) in order to describe three multilevel regimes in Lesotho. For each regime we then observe whether it adheres to the structure features of AM. Finally, we evaluate the extent to which the outcomes, natural resource management projects, are conducive to Ostrom's (1990) ‘design principles’ for sustainable common-pool resource management. We find that, though no ideal ‘adaptive regime’ is found in Lesotho, the results confirm the AM hypotheses that decentralised decision-making, open information sources, and plurality of user interests lead to improved outcomes. Conversely, elements of the climate regime are found not to be adaptive. Our findings also confirm the appropriateness of AM as a governance approach to climate adaptation.

Resume La fievre de la vallee du Rift est une arbovirose tropicale, decrite en 1931 au Kenya, due a un bunyavirus (du genre Phlebovirus ), qui atteint un grand nombre d’animaux domestiques et sauvages ainsi que l’homme. L’homme peut se contaminer directement au contact des animaux et par les vecteurs ( Aedes et Culex) . La maladie est localisee principalement en Afrique mais parfois aussi aux Comores, dans la peninsule arabique, au Yemen et en Egypte. Les troubles cliniques sont frequents chez l’animal, provoquant des avortements chez les femelles gestantes et une mortalite elevee chez les nouveau-nes. L’atteinte humaine apparait lors des epizooties et se manifeste par de la fievre, des arthralgies, des troubles digestifs puis un ictere, des douleurs abdominales, un syndrome confusionnel et parfois des manifestations hemorragiques. Il existe un vaccin pour l’animal qui, associe aux mesures antimoustiques, devrait pouvoir reduire la prevalence de cette arbovirose.

We released the native mosquito fish, Cnesterodon decemmaculatus, into suburban 37 drainage ditches to evaluate its potential as a long-acting agent for the control of CulexCnesterodon decemmaculatus, into suburban 37 drainage ditches to evaluate its potential as a long-acting agent for the control of CulexCulex 38 pipiens larvae in natural breeding sites. The inoculation of predatory fish was conducted in 9 ditches at three densities: 1, 7, and 13 fish/m2 39 during a 2-year period (2006—2008). 40 The number of immature stages of Cx. pipiens was recorded before and after release. On 41 a monthly basis, the digestive-tract contents of some fish and the average number of 42 offspring from the females was recorded. Fifteen weeks after release, a 99% reduction 43 in the number of immature mosquito stages was recorded in the drainage ditches containing 13 fish/m244 , while at 22 weeks, a 99% reduction was also observed in those with 7 fish/m2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatuspipiens larvae in natural breeding sites. The inoculation of predatory fish was conducted in 9 ditches at three densities: 1, 7, and 13 fish/m2 39 during a 2-year period (2006—2008). 40 The number of immature stages of Cx. pipiens was recorded before and after release. On 41 a monthly basis, the digestive-tract contents of some fish and the average number of 42 offspring from the females was recorded. Fifteen weeks after release, a 99% reduction 43 in the number of immature mosquito stages was recorded in the drainage ditches containing 13 fish/m244 , while at 22 weeks, a 99% reduction was also observed in those with 7 fish/m2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatus2 39 during a 2-year period (2006—2008). 40 The number of immature stages of Cx. pipiens was recorded before and after release. On 41 a monthly basis, the digestive-tract contents of some fish and the average number of 42 offspring from the females was recorded. Fifteen weeks after release, a 99% reduction 43 in the number of immature mosquito stages was recorded in the drainage ditches containing 13 fish/m244 , while at 22 weeks, a 99% reduction was also observed in those with 7 fish/m2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatusCx. pipiens was recorded before and after release. On 41 a monthly basis, the digestive-tract contents of some fish and the average number of 42 offspring from the females was recorded. Fifteen weeks after release, a 99% reduction 43 in the number of immature mosquito stages was recorded in the drainage ditches containing 13 fish/m244 , while at 22 weeks, a 99% reduction was also observed in those with 7 fish/m2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatus244 , while at 22 weeks, a 99% reduction was also observed in those with 7 fish/m2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatus2. The ditches with 1 fish/m2 45 had lower densities of immature mosquito 46 stages relative to the controls, but over the entire experiment these observations did not 47 prove statistically significant. The number of offspring per adult C. decemmaculatusC. decemmaculatus 48 female ranged from 4 ± 1.4 (mean ± SD) to 7.4 ± 0.9. Larval remains were detect. Fil: Tranchida, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Pelizza, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Bisaro, V.. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina Fil: Beltrán, C.. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina Fil: Garcia, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina Fil: Micieli, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentina

It is well-established that plants use cytoplasmic, post-transcriptional gene silencing (PTGS) as a defense against RNA viruses and DNA virus transcripts. More recently, it has become clear that small RNA-directed methylation leading to transcriptional gene silencing (TGS) is also used as a defense against DNA virus chromatin. Here we use the DNA-containing geminiviruses as models to discuss what is currently known about both types of antiviral silencing, and viral suppression of PTGS and TGS as a counterdefense.

Resume Objectif Les actinomycoses sont des affections chroniques dues a des bacteries filamenteuses anaerobies, les Actinomyces, se manifestant sous forme de tumefaction sous-cutanee, inflammatoire chronique le plus souvent, en zone cervicofaciale. Cas cliniques Trois cas cliniques illustrent cette mise au point. Une patiente de 41 ans, porteuse d’un sterilet, a consulte pour une masse pelvienne. Le diagnostic a ete etabli par la biopsie et la guerison a ete obtenue par la penicilline. Un patient de 56 ans, alcoolotabagique avec un etat dentaire defectueux a consulte pour un affaiblissement de l’etat general et des tumefactions au niveau du cou, avec du pus contenant des grains jaunes actinomycosiques qui ont gueri sous antibiotiques. Une fillette de huit ans presentait un syndrome infectieux et une plaie thoracique avec des grains bien visibles, identifies en culture comme Actinomyces israelii . Elle a gueri apres deux mois de penicilline. Discussion Les actinomycetes ( A. israelii, Actinomyces bovis ) sont des saprophytes cosmopolites de la cavite buccale et du tube digestif de l’homme et des animaux. Il s’agit de bacteries filamenteuses ramifiees avec des renflements terminaux en « massue », qui proliferent sur des terrains particuliers (traumatisme de la cavite buccale, diabete, leucemie, corticotherapie, insuffisance renale, immunodepression). Elles forment dans la region cervicofaciale des tumefactions inflammatoires sous-cutanees qui peuvent fistuliser et laisser sourdre du pus avec des grains de couleur variable. De nombreux organes peuvent etre atteints (cerveau, poumon, rein, foie, os…). La culture du pus permet l’identification des souches. Le traitement par antibiotiques est efficace. Conclusion Devant une suppuration sous-cutanee ou viscerale trainante, laissant sourdre des grains, il faut savoir evoquer une actinomycose et traiter par un antibiotique adapte.

Resume Objectif Le Demodex folliculorum est un petit acarien frequemment retrouve au niveau de la peau grasse du visage (front, nez, joues, menton) et des cils. Cet ectoparasite etant mal connu, une mise au point actuelle n’est pas inutile. Cas cliniques Une etude, realisee sur 30 personnes atteintes de blepharite, a montre une infestation par Demodex dans 26,6 % des cas qui ont ete traites par pommade a l’oxyde de mercure. Aucun patient n’avait de rosacee. Epidemiologie et pathogenicite L’infestation humaine par les Demodex est frequente, mais elle est le plus souvent asymptomatique. Son role dans la genese de la blepharite ou de la rosacee est discute. Il faut neanmoins savoir y penser devant une blepharite ou une rosacee recidivante, en particulier chez les sujets immunodeficients. Diagnostic et traitement Le diagnostic est base sur la mise en evidence du Demodex dans les squames cutanees ou sur les cils. L’interpretation du role pathogene est discutee en fonction du nombre d’ectoparasites et de l’aspect clinique. Le traitement est essentiellement local.

Resume En milieu tropical, il est frequent de constater une infestation parasitaire chez une femme enceinte. Le paludisme est la parasitose la plus frequente avec un retentissement important sur la grossesse (anemie, acces pernicieux, avortement) et sur le fœtus (faible poids de naissance, paludisme congenital) surtout chez les primipares. Le risque de paludisme congenital est plus frequent chez la touriste (10 % des naissances d’enfants de femmes atteintes de paludisme) que chez la femme autochtone (0,5 %). Le diagnostic doit etre rapidement etabli et le traitement est efficace avec la plupart des antipaludiques actuels. Outre les protections contre les moustiques, la chimioprophylaxie est necessaire. Elle est proposee actuellement en zone d’endemie de facon intermittente par l’association sulfadoxine-pyrimethamine.

Resume Objectifs Description et epidemiologie d’une zoonose tres etendue dans le monde. L’hydatidose est une zoonose atteignant l’homme et de nombreux animaux. Epidemiologie Le taenia du chien, Echinococcus granulosus est un petit taenia avec une larve de grande taille. Differentes souches ont ete identifiees par l’analyse ADN, selon les hotes intermediaires (moutons, porcs, chevaux, chameaux) et les hotes definitifs (canides). Les œufs sont repandus dans les pâturages par le vent et l’eau, ou ils sont ingeres par les hotes intermediaires. Les larves migrent a travers la paroi intestinale et penetrent dans les organes (essentiellement le foie et les poumons). Les œufs peuvent survivre plusieurs jours dans la nature, selon la temperature, mais sont detruits par la dessiccation et les temperatures extremes (− 7° C et + 6° C). Au Turkana (Kenya), l’incidence de l’hydatidose est tres elevee, en raison du rapport etroit entre la population et les chiens ainsi que l’habitude de laisser les cadavres humains dans les prairies. Incidences et clinique chez l’homme Les hotes varient selon les regions : les chiens et les moutons pour E.g. granulosus en Europe, les canides et les cerfs en Europe boreale par E.g. borealis et les loups et les rennes pour E.g. canadensis, sans atteinte de l’homme. Les symptomes varient selon l’organe atteint (foie, poumon, cœur, rein, os, muscles). Diagnostic Le diagnostic de l’hydatidose est base sur l’imagerie medicale et le serodiagnostic. Traitement et prophylaxie L’ablation chirurgicale en est le traitement radical parfois associe a l’albendazole pendant plusieurs mois ou annees. La prophylaxie necessite de couper le cycle, en traitant les chiens et en detruisant les cadavres de moutons infestes. Dans certains pays (Tasmanie, Chypre), une prophylaxie intensive a permis de reduire considerablement l’incidence de l’hydatidose humaine et animale.

Summary Fire is a common phenomenon in grasslands but there is little experimental evidence of the mechanism involved in the rapid recovery of the plant growth. We tested under controlled conditions the hypothesis that after fire Spartina argentinensis leaves that restart growing have high photosynthetic rates. Photosynthetic rates and emergence of leaves and culms were registered. Initial photosynthetic rates were higher among plants which restarted growth after fire or clipping than in control ones, without effect of different water availability. High photosynthetic rate values remained during two months after fire or clipping treatments though then affected by water availability, and thereafter started declining towards the end of season. From January onwards no differences among treatments were detected except that control plants under water stress conditions had lower photosynthetic rates than all others. Leaf and culm emergence were promoted by both fire and clipping treatments. Though affect-ed by water availability, burned and clipped plants had the highest percentages of living tissues at the end of the experiment. Considering photosynthetic and growth responses after fire it can be concluded that burning is a regular component of the subtropical-temperate S. argentinensis habitat, among the South American grasslands.

The effect of indium surface segregation during the molecular beam epitaxial growth of AlSb and GaSb on In(As,Sb) is investigated using various techniques including reflection high-energy electron diffraction (RHEED), high-resolution transmission electron microscopy (HRTEM), and high-resolution X-ray diffraction (HRXRD). The peculiar RHEED intensity variation observed during the growth of AlSb and GaSb on In(As,Sb) is interpreted as the consequence of indium surface segregation. This is confirmed by HRTEM investigation. The interface width associated with In segregation is found to increase with the growth temperature, as expected for a kinetically limited surface segregation phenomenon. In the investigated growth temperature range (400–540°C), the In segregation length is always higher for GaSb than for AlSb. Finally, a very good agreement between simulated and experimental HRXRD data corresponding to a GaSb/InAs superlattice is obtained by taking into account the In segregation profile deduced from the RHEED data.

Transient expression studies using a Nicotiana benthamiana suspension cell-derived protoplast system have identified a minimal sequence that is necessary and sufficient for activation of the tomato golden mosaic virus coat protein (CP) promoter by the viral TrAP protein (also called AL2). The sequence has a bipartite arrangement in which elements located between -125 to -107 and -96 to -60 from the transcription start site are both required for TrAP-mediated activation. One of the sequences (-96 to -60) also appears to interact with a repressor, as its deletion increases basal promoter activity in the absence of TrAP. That competition experiments using the -107 to -60 sequence to titrate the repressor also resulted in increased basal transcription is consistent with this idea. Thus, in a protoplast system which models mesophyll, regulation of the minimal CP promoter involves both activation and derepression by TrAP.

We have investigated the microstructure and the magnetic properties of Sr 2 FeMoO 6 thin films deposited on (0 0 1)-SrTiO 3 substrates by pulsed laser deposition. We have checked the influence of oxygen pressure on the roughness and the resistivity of the films. We found a narrow range of pressure (∼5×10 −6 Torr) leading to conductive films. Fixing the oxygen pressure at this value, we have performed a structural analysis for two characteristic samples grown at different temperatures. We have revealed the nucleation of iron-rich parasitic phases, the content of which depends on the growth temperature. The role of these Fe-rich inclusions on the electrical and magnetic properties of the SrFeMoO 6 films is also discussed.

Vascular puncture inoculation (VPI) is an effective technique for transmission of maize viruses without using arthropods or other biological vectors. It involves using a jeweler's engraving tool to push minuten pins through a droplet of virus inoculum toward the major vascular bundle in the scutellum of germinating kernels. Here, VPI is shown to be useful for introducing RNA and DNA viral genomes into maize. Maize dwarf mosaic potyvirus (MDMV) virions, MDMV genomic RNA, foxtail mosaic potexvirus (FoMV) genomic RNA and maize streak geminivirus (MSV) DNA were introduced into kernels by VPI, and infection rates determined. At high concentrations, both MDMV virion and genomic RNA preparations produced 100% infection of susceptible maize. However, MDMV genomic RNA was transmitted with about 100-fold lower efficiency than virions. FoMV genomic RNA and MSV DNA were transmitted at lower efficiency than the MDMV RNA, and the highest transmission rates were about 50%. Ribonuclease A pretreatment prevented genomic MDMV and FoMV RNA transmission, but not MDMV virion transmission indicating the viral RNA was the infectious entity. Proteinase K (ProK) pretreatment reduced transmission of MDMV RNA suggesting that integrity of the viral genomic protein bound covalently to the viral RNA may be important for efficient transmission.

The purpose of this work was to determine whether some soil physical and chemical properties, and microbial activity were affected by two conservation tillage systems in a Chernozemic clay loam soil (Vertic Argiudoll), after 5 years of trial initiation. Two crop sequences, corn (Zea mays L.)-wheat (Triticum aestivum L.)/soybean (Glycine max (L.) Merr.) and wheat/ soybean, under chisel plowing (ChP) and no till (NT) were evaluated. Physical and chemical properties were also analyzed taking the same soil without disturbance as reference. The Henin instability index (HI) was larger in ChP than in NT in both corn-wheat/soybean (C-W/S) and wheat/soybean (W/S) sequences ðP � 0:05Þ. The C-W/S sequence differed from W/S ðP � 0:01Þ in total organic carbon (TOC). As regards organic carbon fractions, no differences were found in labile organic carbon (LOC), while W/S under ChP showed the lowest value ðP � 0:01Þ of humified organic carbon (HOC). No differences were found in microbial respiration either in crop sequences or in tillage systems. Soil physical and chemical properties differentiated crop sequences and tillage treatments from the undisturbed soil when a Student's t-test was performed. Five years elapsed since the beginning of this trial was time enough to detect changes in some of the soil properties as a consequence of management practices. An important reduction in the soil structural stability was observed as related to the undisturbed soil. However, the C-W/S sequence under NT resulted in lower soil degradation with respect to the other treatments. # 2001 Elsevier Science B.V. All rights reserved.