Abstract

The majority of aquatic carnivorous plants (ACPS; Aldrovanda , Utricularia ) usually grow in shallow dystrophic waters. In these habitats, rootless ACPs usually grow together with rooted aquatic non-carnivorous plants (N-ACPs). Yet species diversity of rooted N-ACPs in dystrophic lakes is relatively poorer than that of abundant ACPs. If generally true, why do rootless ACPs prefer growing in shallow dystrophic waters and why is the occurrence of rooted N-ACPs in these waters limited? These questions are elucidated on the basis of different specific adaptive traits of both functional groups and a different treatment of external habitat factors on both plant groups.

Keywords

aquatic carnivorous plants, Aldrovanda , Utricularia , submerged rooted plants, free CO2, humic acids, pH, potential species pool, water dystrophy

Abstract

Two submersed macrophytes ( Ceratophyllum demersum and Myriophyllum spicatum ) were exposed to 10 mg Se(IV) L–1, later transferred to water without Se and exposed again to water containing 10 mg Se(IV) L–1 with the aim to observe recovery of the plants. After each transplantation trial, photochemical efficiency of photosystem II, respiratory potential and the amount of photosynthethic pigments and anthocyanins were measured. Photochemical efficiency was similar in all three trials. Electron transport system (ETS) activity increased drastically for C. demersum plants that were transferred from the water with Se to the water without Se, while ETS activity strongly increased in plants of M. spicatum , which once again grew in water containing Se. Alternation in the concentration of Se in the growth media demanded metabolic changes in studied plants. The amount of chlorophylls was higher in plants of M. spicatum growing in water without Se than in exposed plants, while the amount of carotenoids and anthocyanins decreased in the same species grew in water without Se.

Keywords

Myriophyllum spicatum , Ceratophyllum demersum , selenium, photochemical efficiency, respiratory potential

Abstract

We tested the applicability of electron transport system (ETS) derived from a single leg as a tool for non-lethal assessment of metabolic activity in freshwater crayfish. ETS activity of the whole body and of a leg was measured in four crayfish (Arthropoda, Crustacea, Decapoda) species: two European ( Astacus astacus, Austropotamobius torrentium ), and two North American ( Orconectes limosus, Pacifastacus leniusculus ). Mass scaling of whole body ETS activity (ETS _whole ) and leg ETS activity (ETS _leg ) was not significantly different for the European A. astacus and the American O. limosus . Therefore common models were constructed and tested on the remaining two species. The ratio ETS _whole /ETS _leg was significantly positively related to body mass. In the first model (model 1) ETSwhole was calculated from ETS _leg multiplied by the ratio estimated from the known body mass. ETS _whole of A. torrentium was underestimated by this model, because they mature at smaller body size than the larger species. A direct relation between ETS _leg and ETS _whole was therefore proposed as a general model (model 2), since they are correlated similarly in the studied species. The results show that model 2 is suitable for estimating the whole body ETS activity from leg ETS activity for the four investigated decapods.

Keywords

electron transport system (ETS) activity, crayfish, size scaling, method

Abstract

As part of the survey of the pan-alpine population of Eurasian Lynx, the French national network of large carnivores experts collected N = 301 data, out of which 159 (n1 = 2 C1, n2 = 62 C2, n3 = 95 C3) were regarded robust enough from a technical point of view to evidence the presence of lynx (compared to 224 data in the previous pentad). Such a rejection rate (46%) significantly differed from that (24%) observed elsewhere in the Lynx area during the same period, but not from that during the previous pentad in the Alps (43%). The rejection rate was dependent on data type: hair and faeces samples were significantly more often rejected than other presence signs (78% vs. 41%). Among other presence signs, prints were more often rejected (55%) than expected, and sightings were less rejected (35%) than expected. Preys were rejected according to expectations given sample sizes. As noted during the previous pentad, a north-south gradient was evidenced in presence signs collected: C1+C2 were more often encountered north to Grenoble than in the southern part of the lynx area, contrary to C3. Using a modelling approach of the trend in the presence area detected, area with regular presence was increasing then stable, whereas a declining trend was noticed in the area newly colonized during the last years.

Keywords

Lynx lynx , France, Alps, presence signs, population trend

Abstract

To assess the status of lynx we analysed lynx signs of presence within the range of the Italian Alps from 2005 to 2009. A total of 268 signs have been collected, compared to 411 signs during the previous pentad. The distribution of the confirmed signs of lynx presence is confined to three concise areas: the North-eastern Alps of Friuli VG, the Trentino province and the Ossola valley in the Piedmont region. Occupancy modelling revealed a decrease of the lynx range by one third: The estimated number of occupied 100 km2 cells decreased from 34 (pentad: 2000–2004) to 21 (pentad: 2005–2009). Less than 10% of the Italian Alps are colonized. We estimated the number of lynx present in all the Italian Alps at less than 15 individuals. Therefore, the persistence of lynx in the Italian Alps highly depends on immigration from neighbouring countries.

Keywords

Alps, distribution, Italy, Lynx lynx, monitoring, occupancy

Abstract

Signs of lynx presence were recorded three times between 2005 and 2009.

Keywords

Lynx lynx , Alps, Liechtenstein, monitoring, distribution

Abstract

Expansins are a group of plant cell wall loosening proteins. In animals, functional expansin (EXPB1) has been discovered in the golden potato cyst nematode Globodera rostochiensis . In plant-parasitic nematodes expansins act as the parasitism factors or effectors. Molecular variability of another expansin (expB2) gene was evaluated in the diverse populations of the G. rostochiensis . Comparison of the expB2 gene structure in the two potato cyst nematode species, G. rostochiensis and G. pallida , revealed lack of all four introns in expB2 gene of G. pallida species. Possible loss of introns in Gp-expB2 is discussed.

Keywords

Cell wall degradation, Globodera pallida , effectors, expansin, intron, parasitism factor, plant-parasitic nematode, potato cyst nematode.