Transdisciplinarity – An Option for Applied Landscape Ecology in Complex and Uncertain Contexts.

Applied landscape ecology is considered to have a limited impact on decision-making. To improve the effectiveness of research, above all, closer cooperation between researchers and nonacademic actors is needed. We argue that a suitable research approach in this context is transdisciplinarity (td). We refer to td as interdisciplinary research that takes place in a complex environment-society context with a strong involvement of non-academic actors during the entire research process. A brief synthesis of a case study focusing on ‘Off-site Effects of Soil Erosion on the Swiss Plateau’ illustrates a promising application of a td approach.

Direct and indirect effects of invasion by the alien tree Ailanthus altissima on riparian plant communities and ecosystem multifunctionality

Most existing studies addressing the effects of invasive species on biodiversity focus on species richness ignoring better indicators of biodiversity and better predictors of ecosystem functioning such as the diversity of evolutionary histories (phylodiversity). Moreover, no previous study has separated the direct effect of alien plants on multiple ecosystem functions simultaneously (multifunctionality) from those indirect ones mediated by the decrease on biodiversity caused by alien plants. We aimed to analyze direct and indirect effects, mediated or not by its effect on biodiversity, of the invasive tree Ailanthus altissima on ecosystem multifunctionality of riparian habitats under Mediterranean climate. We measured vegetation attributes (species richness and phylodiversity) and several surrogates of ecosystem functioning (understory plant biomass, soil enzyme activities, available phosphorous and organic matter) in plots infested by A. altissima and in control (non-invaded) ones. We used structural equation modelling to tease apart the direct and indirect effects of A. altissima on ecosystem multifunctionality. Our results suggest that lower plant species richness, phylodiversity and multifunctionality were associated to the presence of A. altissima. When analyzing each function separately, we found that biodiversity has the opposite effect of the alien plant on all the different functions measured, therefore reducing the strength of the effect (either positive or negative) of A. altissima on them. This is one of the few existing studies addressing the effect of invasive species on phylodiversity and also studying the effect of invasive species on multiple ecosystem functions simultaneously.

Invasion and persistence of Mycoplasma bovis in embryonic calf turbinate cells.

Mycoplasma bovis is a wall-less bacterium causing bovine mycoplasmosis, a disease showing a broad range of clinical manifestations in cattle. It leads to enormous economic losses to the beef and dairy industries. Antibiotic treatments are not efficacious and currently no efficient vaccine is available. Moreover, mechanisms of pathogenicity of this bacterium are not clear, as few virulence attributes are known. Microscopic observations of necropsy material suggest the possibility of an intracellular stage of M. bovis. We used a combination of a gentamicin protection assay, a variety of chemical treatments to block mycoplasmas entry in eukaryotic cells, and fluorescence and transmission electron microscopy to investigate the intracellular life of M. bovis in calf turbinate cells. Our findings indicate that M. bovis invades and persists in primary embryonic calf turbinate cells. Moreover, M. bovis can multiply within these cells. The intracellular phase of M. bovis may represent a protective niche for this pathogen and contribute to its escape from the host's immune defense as well as avoidance of antimicrobial agents.

Blood and lymphatic vessel invasion in pT1 colorectal cancer: an international concordance study

AIM This study was performed to evaluate the concordance in pathological assessments of blood and lymphatic vessel invasion (BLI) in pT1 colorectal cancers and to assess the effect of diagnostic criterion on consistency in the assessment of BLI. METHODS Forty consecutive patients undergoing surgical resection of pT1 colorectal cancers were entered into this study. H&E-stained, D2-40-stained and elastica-stained slides from the tumours were examined by 18 pathologists from seven countries. The 40 cases were divided into two cohorts with 20 cases each. In cohort 1, pathologists diagnosed BLI using criteria familiar to them; all Japanese pathologists used a criterion of BLI from the Japanese Society for Cancer of the Colon and Rectum (JSCCR). In cohort 2, all pathologists used the JSCCR diagnostic criterion. RESULTS In cohort 1, diagnostic concordance was moderate in the US/Canadian and European pathologists. There were no differences in the consistency compared with results for Japanese pathologists, and no improvement in the diagnostic concordance was found for using the JSCCR criterion. However, in cohort 2, the JSCCR criterion decreased the consistency of BLI diagnosis in the US/Canadian and European pathologists. The level of decreased consistency in the assessment of BLI was different between the US/Canadian and European pathologists. CONCLUSIONS A uniform criterion strongly influences the diagnostic consistency of BLI but may not always improve the concordance. Further study is required to achieve an objective diagnosis of BLI in colorectal cancer. The varying effects of diagnostic criterion on the pathologists from Japan, the USA/Canada and Europe might reflect varied interpretations of the criterion. Internationally accepted criterion should be developed by participants from around the world.

Disentangling the role of phenotypic plasticity and genetic divergence in contemporary ecotype formation during a biological invasion

The occurrence of contemporary ecotype formation through adaptive divergence of populations within the range of an invasive species typically requires standing genetic variation but can be facilitated by phenotypic plasticity. The relative contributions of both of these to adaptive trait differentiation have rarely been simultaneously quantified in recently diverging vertebrate populations. Here we study a case of intraspecific divergence into distinct lake and stream ecotypes of threespine stickleback that evolved in the past 140 years within the invasive range in Switzerland. Using a controlled laboratory experiment with full-sib crosses and treatments mimicking a key feature of ecotypic niche divergence, we test if the phenotypic divergence that we observe in the wild results from phenotypic plasticity or divergent genetic predisposition. Our experimental groups show qualitatively similar phenotypic divergence as those observed among wild adults. The relative contribution of plasticity and divergent genetic predisposition differs among the traits studied, with traits related to the biomechanics of feeding showing a stronger genetic predisposition, whereas traits related to locomotion are mainly plastic. These results implicate that phenotypic plasticity and standing genetic variation interacted during contemporary ecotype formation in this case.

The Nile perch invasion in Lake Victoria: cause or consequence of the haplochromine decline?

We review alternative hypotheses and associated mechanisms to explain Lake Victoria’s Nile perch takeover and concurrent reduction in haplochromines through a (re)analysis of long term climate, limnological and stock observations in comparison with size-spectrum model predictions of co-existence, extinction and demographic change. The empirical observations are in agreement with the outcomes of the model containing two interacting species with life-histories matching Nile perch and a generalized haplochromine. The dynamic interactions may have depended on size related differences in early juvenile mortality: mouth-brooding haplochromines escape predation mortality in early life stages, unlike Nile perch that have miniscule planktonic eggs and larvae. In our model predation on the latter by planktivorous haplochromine fry act as a stabilizing factor for co-existence, but external mortality on the haplochromines would disrupt this balance in favor of Nile perch. To explain the observed switch, mortality on haplochromines would need to be much higher than the fishing mortality that can be realistically re-constructed from observations. Abrupt concomitant changes in algal and zooplankton composition, decreased water column transparency, and widespread hypoxia from increased eutrophication most likely caused haplochromine biomass decline. We hypothesize that the shift to Nile perch was a consequence of an externally caused, climate triggered, decrease in haplochromine biomass and associated recruitment failure rather than a direct cause of the introduction.

Does autogamy contribute to invasion in Lilium formosanum?

The Taiwanese geophyte Lilium formosanum is invasive in the eastern parts of South Africa. Although it is capable of autogamy, a pollinator, the hawkmoth Agrius convolvuli, is present. Reproduction may therefore take place both by self- and cross-fertilisation. The relative importance of these modes of pollination for seed production is evaluated using emasculation experiments. The potential contributions of outcrossed and selfed progeny to invasion are assessed in progeny performance trials.

Fire ecology north and south of the Alps since the last ice age

Wildfires are very rare in central Europe, which is probably why fire effects on vegetation have been neglected by most central European ecologists and palaeoecologists. Presently, reconstructions of fire history and fire ecology are almost absent. We analysed sediment cores from lakes on the Swiss Plateau (Lobsigensee and Soppensee) for pollen and charcoal to investigate the relationship between vegetation and fire. Microscopic charcoal evidence suggests increasing regional fire frequencies during the Neolithic (7350-4150 cal. BP, 5400-2200 BC) and the subsequent prehistoric epochs at Lobsigensee, whereas at Soppensee burnings remained rather rare until modern times. Neolithic peaks of charcoal at 6200 and 5500 cal. BP (4250 and 3550 BC) coincided with declines of pollen of fire-sensitive taxa at both sites (e.g., Ulmus, Tilia, Hedera, Fagus), suggesting synchronous vegetational responses to fire at regional scales. However, correlation analysis between charcoal and pollen for the period 6600-4400 cal. BP (4650-2650 BC) revealed no significant link between fire and vegetation at Soppensee, whereas at Lobsigensee increases of Corylus and decreases of Fagus were related to fire events. Fire impact on vegetation increased during the subsequent epochs at both sites. Correlation analyses of charcoal and pollen data for the period 4250-1150 cal. BP (2300 BC -AD 800) suggest that fires were intentionally set to disrupt forests and to provide open areas for arable and pastoral farming (e.g., significant positive correlations between charcoal and Cerealia, Plantago lanceolata, Asteroideae). These results are compared with southern European records (Lago di Origlio, Lago di Muzzano), which are situated in particularly fire-prone environments. After the Mesolithic period (I1 200-7350 cal. BP, 9250-5400 BC), charcoal influx was higher by an order of magnitude in the south, suggesting more frequent fires. Neolithic fires caused similar though more pronounced responses of vegetation in the south (e.g., expansions of Corylus). Post-Neolithic land-use practices involving (controlled) burning culminated in both regions at about 2550 cal. BP (c. 600 BC). However, fire-caused disappearances of entire forest communities were confined to the southern sites. Such differences in fire effects among the sites are explained by the dissimilar importance of fire as a result of different climatic conditions and cultural activities. Our results imply that the remaining (fire-sensitive) fragments of central European vegetation north of the Alps are especially endangered by increasing fire frequencies resulting from predicted climatic change.

Prognostic Implication of Lymphovascular Invasion Detected by Double Immunostaining for D2-40 and MITF1 in Primary Cutaneous Melanoma.

BACKGROUND Lymphovascular invasion (LVI) is associated with adverse outcomes in primary cutaneous melanoma (PCM). Detection of LVI by hematoxylin and eosin staining alone is 0%-6%, but targeting lymphovascular structures increases the detection rate. OBJECTIVE To examine the prognostic significance of LVI detected by immunostaining for D2-40 and microphthalmia-associated transcription factor 1 (MITF1) in PCM. METHODS The authors retrospectively analyzed 120 PCM samples. We compared the LVI detection rates of immunostaining for D2-40 only (22%), double staining for D2-40 and MITF1 (38%), and hematoxylin and eosin, and examined the association of LVI with clinicopathologic variables and clinical outcomes. RESULTS Immunolabeling with both methods significantly increased the LVI detection rate. Double staining for D2-40 and MITF1 as well as D2-40-detected LVI was significantly associated with increased Breslow thickness, number of mitoses, and sentinel lymph node (SLN) metastasis. D2-40-detected LVI was also associated with ulceration. Although the difference was not significant, double staining for D2-40 and MITF1 allowed for easier detection of LVI than D2-40 alone. LIMITATIONS This study was conducted in a tertiary referral institution; therefore, a referral bias cannot be excluded. CONCLUSIONS Immunolabeling increased detection of LVI in PCM. Because LVI is a positive predictive marker for SLN metastasis, the authors propose using anti-D2-40 and anti-MITF1 in the evaluation of LVI in patients with PCM with a certain risk of SLN metastasis.

Aus dem Schreiben eines russischen Generals an einen Verwandten in Berlin: Was wir von einer russischen Invasion etwa zu erwarten haben, darüber giebt uns folgender Brief ein Bild ...: Petersburg, den 13. März alten Styles (26. April) 1848: In meinem glücklichen Vaterlande leben wir guten Muthes unter dem Schutze weiser Gesetze ...

Welsch (Projektbearbeiter): Abdruck eines - tatsächlichen oder fiktiven - Briefes eines ungenannten russischen Generals, in dem dieser angesichts der revolutionären Geschehnisse in Preußen - "Noch nie war die Menschheit ... so tief herabgesunken vom Throne der Gottheit und Wahrheit als jetzt ..." - die vermeintlich gerechten und revolutionsresistenten Zustände seiner Heimat preist: "Denn hier zu Lande ist das Vertrauen zu Gott und zum Monarchen felsenfest und unerschüttert."

Long-term forest fire ecology and dynamics in southern Switzerland

1 Pollen and charcoal analysis at two lakes in southern Switzerland revealed that fire has had a prominent role in changing the woodland composition of this area for more than 7000 years. 2 The sediment of Lago di Origlio for the period between 5100 and 3100 bc cal. was sampled continuously with a time interval of about 10 years. Peaks of charcoal particles were significantly correlated with repeated declines in pollen of Abies, Hedera, Tilia, Ulmus, Fraxinus excelsior t., Fagus and Vitis and with increases in Alnus glutinosa t., shrubs (e.g. Corylus, Salix and Sambucus nigra t.) and several herbaceous species. The final disappearance of the lowland Abies alba stands at around 3150 bc cal. may be an example of a fire-caused local extinction of a fire-intolerant species. 3 Forest fires tended to diminish pollen diversity. The charcoal peaks were preceded by pollen types indicating human activity. Charcoal minima occurred during periods of cold humid climate, when fire susceptibility would be reduced. 4 An increase of forest fires at about 2100 bc cal. severely reduced the remaining fire-sensitive plants: the mixed-oak forest was replaced by a fire-tolerant alder–oak forest. The very strong increase of charcoal influx, and the marked presence of anthropogenic indicators, point to principally anthropogenic causes. 5 We suggest that without anthropogenic disturbances Abies alba would still form lowland forests together with various deciduous broadleaved tree taxa.