共基质对10株细菌降解苯并芘的作用研究

从石油污染的污泥中分离驯化出10株细菌（SB01-SB10）,利用生物摇床实验对其降解苯并芘（BaP）的效能进行试验,研究了有（或无）共基质（葡萄糖Glu,或菲PHE）对细菌降解BaP的影响,并采用ANOVA和Tukey多重比较进行分析。结果表明,（1）当以BaP为惟一碳源和能源且BaP初始浓度为50mg·L^-1时（MS1）,SB01的降解率最高,5d可降解31．0％;以Glu为共代谢基质时（MS2）,SB09的降解率最高,可达36．9％;以PHE为共代谢基质时（MS3）,SB01对BaP的降解率为46．0％。（2）Glu对SB01、SB02、SB03、SB07、SB10降解BaP有抑制作用,对SB01抑制作用最明显,使SB01的降解率降低了13．1％,Glu对SB05,SB08降解率无明显促进或抑制作用。（3）PHE对细菌降解BaP均表现出促进作用,对SB01的促进作用最明显,使其降解率提高15．0％。（4）Glu对SB09的促进作用大于PHE的促进作用。而对SB06,PHE的促进作用大于Glu。     

Presence–absence surveys of prey and their use in predicting leopard (Panthera pardus) densities: a case study from Armenia

It is important to predict how many individuals of a predator species can survive in a given area on the basis of prey sufficiency and to compare predictive estimates with actual numbers to understand whether or not key threats are related to prey availability. Rugged terrain and low detection probabilities do not allow for the use of traditional prey count techniques in mountain areas. We used presence–absence occupancy modeling and camera‐trapping to estimate the abundance and densities of prey species and regression analysis to predict leopard (Panthera pardus) densities from estimated prey biomass in the mountains of the Nuvadi area, Meghri Ridge, southern Armenia. The prey densities were 12.94 ± 2.18 individuals km^?2 for the bezoar goat (Capra aegagrus), 6.88 ± 1.56 for the wild boar (Sus scrofa) and 0.44 ± 0.20 for the roe deer (Capreolus capreolus). The detection probability of the prey was a strong function of the activity patterns, and was highest in diurnal bezoar goats (0.59 ± 0.09). Based on robust regression, the estimated total ungulate prey biomass (720.37 ± 142.72 kg km^?2) can support a leopard density of 7. 18 ± 3.06 individuals 100 km^?2. The actual leopard density is only 0.34 individuals 100 km^?2 (i.e. one subadult male recorded over the 296.9 km²), estimated from tracking and camera‐trapping. The most plausible explanation for this discrepancy between predicted and actual leopard density is that poaching and disturbance caused by livestock breeding, plant gathering, deforestation and human‐induced wild fires are affecting the leopard population in Armenia.