This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It i...This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It is found that ametryn was the most effective herbicide that inhibited algal growth. Ametryn concentration that caused 50% inhibition on algae growth after exposure for 21 days was 0.335 ppm. Survival rate of oruamental fish, Harlequin rasbora （Trigonostigma heteromorpha） and growth rate of aquatic plant （Elodea canadensis） exposed to 10 ppm ametryn were compared with those exposed to algaecide. The result showed that there was no significant difference in survival rate of Harlequin rasbora when exposed to ametryn, algaecide and dechlorinized tap water （control）. However, growth rate of E. canadensis was lower after exposure of ametryn compared to those exposed to algaecide and tap water. These results suggest that ametryn has potential to be used as an algal inhibitor in aquarium.展开更多
Animal habitat-use patterns cannot be isolated from scale issues. Consequently, multi-scale studies provide a complete characterization of ecological patterns that can further explain the observed variation. Liolaemus...Animal habitat-use patterns cannot be isolated from scale issues. Consequently, multi-scale studies provide a complete characterization of ecological patterns that can further explain the observed variation. Liolaemus constitutes the world＇s second most speciose lizard genus. In this study, we assessed the relationships between home range size and environmental variables at 3 different spatial scales. The study at a local and regional scale was focused on the habitat specialist Liolaemus multimaculatus. The lizard＇s home range was calculated using the minimum convex polygon method in populations from grassland sites of the coastal sand dunes of the Argentinean Pampas under 2 different conditions, with or without forestations of Acacia Iongifolia. On the other hand, at a geographical scale we considered the evolutionary implications of 20 species of Liolaemus. Home range size, phylogeny, ecological, environmental, and climatic data were ob- tained from the literature and remote sensing. L. multimaculatus home range varied from 12.66 to 570.00 m. Regionally, this species had smaller home ranges in forested habitats （X： 94.02 m2） com- pared with the non-forested sites （X： 219.78m2）. Habitat structure, vegetation types, and food availability would explain the space use at finer scales. When the 20 species of Liolaernus were considered, high mean air temperature and broad thermal amplitudes showed an inverse relationship with home range size. Neither net primary productivity nor phylogeny was good predictors for home range variation at geographical scale. This study highlights the scale dependence of the explicative capability of a set of environmental and intrinsic variables on home range patterns.展开更多
文摘This study was conducted to screen the commercial herbicides for algae control in the aquarium. Three herbicides of ametryn, atrazine and metribuzine were tested at concentrations ranging from 0.625 to 10.00 ppm. It is found that ametryn was the most effective herbicide that inhibited algal growth. Ametryn concentration that caused 50% inhibition on algae growth after exposure for 21 days was 0.335 ppm. Survival rate of oruamental fish, Harlequin rasbora （Trigonostigma heteromorpha） and growth rate of aquatic plant （Elodea canadensis） exposed to 10 ppm ametryn were compared with those exposed to algaecide. The result showed that there was no significant difference in survival rate of Harlequin rasbora when exposed to ametryn, algaecide and dechlorinized tap water （control）. However, growth rate of E. canadensis was lower after exposure of ametryn compared to those exposed to algaecide and tap water. These results suggest that ametryn has potential to be used as an algal inhibitor in aquarium.
文摘Animal habitat-use patterns cannot be isolated from scale issues. Consequently, multi-scale studies provide a complete characterization of ecological patterns that can further explain the observed variation. Liolaemus constitutes the world＇s second most speciose lizard genus. In this study, we assessed the relationships between home range size and environmental variables at 3 different spatial scales. The study at a local and regional scale was focused on the habitat specialist Liolaemus multimaculatus. The lizard＇s home range was calculated using the minimum convex polygon method in populations from grassland sites of the coastal sand dunes of the Argentinean Pampas under 2 different conditions, with or without forestations of Acacia Iongifolia. On the other hand, at a geographical scale we considered the evolutionary implications of 20 species of Liolaemus. Home range size, phylogeny, ecological, environmental, and climatic data were ob- tained from the literature and remote sensing. L. multimaculatus home range varied from 12.66 to 570.00 m. Regionally, this species had smaller home ranges in forested habitats （X： 94.02 m2） com- pared with the non-forested sites （X： 219.78m2）. Habitat structure, vegetation types, and food availability would explain the space use at finer scales. When the 20 species of Liolaernus were considered, high mean air temperature and broad thermal amplitudes showed an inverse relationship with home range size. Neither net primary productivity nor phylogeny was good predictors for home range variation at geographical scale. This study highlights the scale dependence of the explicative capability of a set of environmental and intrinsic variables on home range patterns.
