Direct Radiative Forcing by Smoke from Biomass Burning

Airborne measurements in smoke from biomass burning in Brazil have yielded optical parameters that permit an improved assessment of the effects of smoke on Earth's radiation balance. The global-mean direct radiative forcing due to smoke from biomass burning worldwide is estimated to be no more than about -0.3 watt per square meter (cooling), compared with +2.45 watts per square meter (warming) due to anthropogenic greenhouse gases. On regional scales, direct radiative forcing due to smoke can be large and might indirectly affect global climate.     

Sexual behaviour in Isotomidae (Collembola)

We studied the sexual behaviour of three isotomid species Vertagopus cinereus, Vertagopus pseudocinereus, and Proisotoma clavipila including (1) stimulation of the female by the male, (2) deposition of spermatophores, and (3) pushing the female over the spermatophore. A variety of behaviour never described before in Isotomidae were observed including fastening of the female abdomen by the antennae of the male, repeated stimulation of the ventral region of the female, and repeated capture of spermatophore by the female. We propose a functional explanation of male sexual secondary characters and of the setae of the abdomen in V. pseudocinereus.     

Comparison of the Ability of Three Radioimmunoassay to Detect Pregnancy-associated Glycoproteins in Bovine Plasma

Pregnancy‐associated glycoproteins (PAGs) constitute a large family of glycoproteins that are synthesized in the superficial layer of the ruminant placenta according to a spatial and temporal expression pattern. When PAGs are released in the maternal blood they can be used for pregnancy diagnosis, pregnancy follow‐up and for the monitoring of the trophoblastic function. Three different radioimmunoassay systems (RIA 1, RIA 2 and RIA 3) using antisera produced against PAG I₆₇ (RIA 1), PAG₅₅₊₆₂ (RIA 2) and PAG₅₅₊₅₉ (RIA 3) were used in this investigation in order to measure the PAG concentration in plasma samples withdrawn from pregnant cows and heifers during different periods following artificial insemination (AI). These systems were able to detect PAG molecules in the maternal blood as early as 21 days after AI in different concentrations (RIA 1: 0.43 ± 0.24 ng/ml, mean ± SD; RIA 2: 0.48 ± 0.24 ng/ml; RIA 3: 0.64 ± 0.37 ng/ml). On days 32 and 42 RIA 2 (4.30 ± 1.32 ng/ml and 5.56 ± 1.95 ng/ml) and RIA 3 (4.17 ± 1.15 ng/ml and 5.60 ± 1.89 ng/ml) presented significantly (p < 0.0001) higher PAG concentrations than those of RIA 1 (2.43 ± 0.81 ng/ml and 4.01 ± 1.48 ng/ml), respectively. After day 21, significant correlations (p < 0.0001; r ≥ 0.929) were determined between the three systems. Additionally the three individual PAG profiles presented in this study showed that PAG molecules secreted in the maternal blood between 21 and 50 days after AI were better recognized by the RIA 2 and RIA 3 systems. This study clearly indicated that the ability of a RIA test to recognize PAG molecules in the maternal blood can be improved by carefully selecting the antiserum.     

Soil mesofauna and diversity of vegetation: Collembola in pristine taiga forests (Pechora-Ilych Biosphere Reserve,Russia)

Unique 600-year-old tall herb taiga forests are located in the European North-East of Russia at the foothills of the Middle Urals and are characterized by extremely diverse and vertically differentiated vegetation. This study addresses how vegetation parameters such as net primary productivity and diversity influence the community structure of Collembola in fir forests of different ages. Sample plots were arranged along diversity and biomass gradients of vegetation: Vaccinium-moss, short herb-moss, and nitrophilous tall herb fir–spruce forests. Plants and collembolans were compared with respect to their species richness, abundance, species structure and traits. The number of species of vascular plants, mosses and liverworts along the studied gradient increased by about double, whereas the species richness of collembolans did not differ significantly. The biomass of vascular plants increased, whereas that of mosses declined, and the abundance of collembolans remained approximately consistent. Despite sharp differences in ground vegetation, in all phytocenoses the dominant Collembola species were widespread. However, the collembolan community of old-growth tall herb forests showed a trend of more complex structure reflected by greater evenness of abundances compared to younger ecosystems with less diverse ground vegetation. In conclusion, the springtail communities in forests that have developed spontaneously for over 600 years appeared to be no more complex than those in 200-year-old stands. Multi-species ground vegetation did not increase collembolan diversity and abundance indices. Thus, soil mesofauna (in this case, springtails) appeared to be relatively independent of long-term spontaneous development in vegetation in the studied area.