The submerged aquatic macrophytes in Lake Maarsseveen I: Species composition, spatial distribution and productivity

1981 ◽  
Vol 15 (1-2) ◽  
pp. 72-81 ◽  
Author(s):  
Elly P. H. Best
Keyword(s):  
Spatial Distribution ◽  
Species Composition ◽  
Aquatic Macrophytes ◽  
Submerged Aquatic Macrophytes

scholarly journals Spatial distribution and temporal variation of microcrustaceans assembly (Cladocera and Copepoda) in different compartments of a reservoir in the brazilian semiarid region

2018 ◽  
Vol 30 (0) ◽  
Author(s):  
Josiane Souza Santos ◽  
Nadson Ressyé Simões ◽  
Sérgio Luiz Sonoda
Keyword(s):  
Spatial Distribution ◽  
Spatial Variation ◽  
Temporal Variation ◽  
Aquatic Macrophytes ◽  
Temporal Dynamics ◽  
Lateral Compartment ◽  
Spatial And Temporal Variation ◽  
Semiarid Region ◽  
Brazilian Semiarid ◽  
Significant Spatial Variation

Abstract Aim: The objective of this study was to investigate the spatial and temporal variation of microcrustacean assemblages of a reservoir in the Brazilian semiarid region. Methods Physical and chemical water variables and samples of microcrustaceans were collected at eight sites of the reservoir between July 2013 and November 2014, in a total of seven campaigns. For this study, the reservoir was categorized in two compartments: lateral and central. Results Limnological variables showed significant temporal variation (PERMANOVA, Pseudo-F = 19.51, p = 0.001). Higher turbidity values and suspended solids were observed in the rainiest months, while during the dry months, we measured higher values of transparency, dissolved oxygen, and chlorophyll-a. It was not found significant spatial variation of limnological variables (PERMANOVA, Pseudo-F = 0.96; p = 0.394). During the study period, ten species were recorded: four Cladocera (Ceriodaphnia cornuta, Daphnia gessneri, Diaphanosoma birgei and Diaphanosoma spinulosum ) three Copepoda Calanoida (Argyrodiaptomus azevedoi, Notodiaptomus cearensis and Notodiaptomus iheringi) and three Copepoda Cyclopoida (Macrocyclops albidus, Thermocyclops minutus and Thermocyclops decipiens). The microcrustacean assemblages showed significant temporal variation (PERMANOVA, Pseudo-F = 4.34; p = 0.001) as well as significant spatial variation (PERMANOVA, Pseudo-F = 9.46; p = 0.001). The highest values of abundance and richness were observed in the lateral compartment, this result is mainly related to the presence of aquatic macrophytes in this region, because the analysis of partial RDA indicated that limnological variables explained only 11% of this variation (Pseudo-F = 2.08, p = 0.001). Conclusions The results suggest that the seasonality of the semiarid is an important factor in the temporal dynamics of the limnological variables, while the aquatic macrophytes play an important role in the spatial distribution of the microcrustacean assembly.

scholarly journals Use of grass carp (Ctenopharyngodon idella) as a biological control agent for submerged aquatic macrophytes

2014 ◽  
Vol 32 (4) ◽  
pp. 765-773
Author(s):  
A.F. Silva ◽  
C. Cruz ◽  
R.L.C.M. Pitelli ◽  
R.A. Pitelli
Keyword(s):  
Grass Carp ◽  
Aquatic Macrophytes ◽  
Biological Control Agent ◽  
Body Weight Gain ◽  
Predation Rate ◽  
Control Agent ◽  
Ctenopharyngodon Idella ◽  
Ceratophyllum Demersum ◽  
Grass Carp Ctenopharyngodon Idella ◽  
Submerged Aquatic Macrophytes

This study aimed to evaluate feed preference and control efficacy of grass carp (Ctenopharyngodon idella) on the aquatic macrophytes Ceratophyllum demersum, Egeria densa and Egeria najas. An experiment was carried out at mesocosms conditions with 2,000 liters capacity and water residence time of 2.8 days. C. demersum, E. densa e E. najas biomasses were offered individually with sixty g and coupled in similar quantities of 30 g of each species, evaluated during 81 days, envolving 6 treatments. (1 - C. demersum, 2 - E. najas, 3 -E. densa, 4 - C. demersum + E. najas, 5 - C. demersum + E. densa and 6 - E. najas + E. densa). When offered individually, E. najas and C. demersum presented the same predation rate by grass carp, which was higher than E. densa predation rate. When plants were tested in pairs, the order of feed preference was C. demersum > E. najas > E. densa. E. najas and C. demersum percentage control ranged from 73 to 83%. No relation between biomass consumption and grass carp body weight gain was observed, probably due to differences in nutritional quality among macrophyte species according to fish necessities. Therefore, it is concluded that the use of grass carp is one excellent technique to control submersed macrophytes in Brazil.

scholarly journals Spatial distribution and species composition of small pelagic fishes in the Gulf of California

2006 ◽  
Author(s):  
Edgar Lanz ◽  
Manuel O. Nevárez Martínez ◽  
Juana López Martínez ◽  
Juan A. Dworak
Keyword(s):  
Spatial Distribution ◽  
Species Composition ◽  
Gulf Of California ◽  
Pelagic Fishes

Some aspects of the ecology of bagrid catfishes in a southern Nigerian river

1991 ◽  
Vol 7 (2) ◽  
pp. 221-232 ◽  
Author(s):  
George Idodo-Umeh ◽  
Reginald Victor
Keyword(s):  
Spatial Distribution ◽  
Species Composition ◽  
Rainy Season ◽  
Major Peak ◽  
Fish Yield ◽  
Southern Nigeria ◽  
Minor Peak ◽  
A Minor ◽  
Principal Species ◽  
Dry And Rainy Seasons

ABSTRACTSome aspects of the ecology of bagrid catfishes in River Ase, southern Nigeria were studied for a period of two years. Nine species of Bagridae were recorded and these accounted for 15.0% of the number and 24.4% of the weight of all fish captured. Chrysichthys nigrodigitatus and Chrysichthys auratus longifilis were the principal species. C. nigrodigitatus was a rainy season species, while C. auratus longifilis was abundant in both dry and rainy seasons. Both species showed a major peak in catches between 0600 and 0900 h. C. nigrodigitatus exhibited a minor peak in catches between 1500 and 2100h, while C. auratus longifilis showed a minor peak between 1500 and 1800h. The spatial distribution of C. nigrodigitatus and C. auratus longifilis populations was heterogeneous. Bagrid fishes were an important component in the fish yield of the study river and its species composition has been compared with those of other Nigerian waters. The distribution and abundance of C. nigrodigitatus and C. auratus longifilis are discussed in detail.

Sign in / Sign up

Export Citation Format

Share Document