Annual Production by Caddisflies and Mayflies in a Western Minnesota Plains Stream

1982 ◽  
Vol 39 (12) ◽  
pp. 1628-1635 ◽  
Author(s):  
M. B. MacFarlane ◽  
T. F. Waters
Keyword(s):  
Standing Stock ◽  
Annual Production ◽  
Insect Community ◽  
Downstream Site ◽  
Frequency Method ◽  
Third Order ◽  
Upstream Site ◽  
Size Frequency ◽  
Total Annual Production ◽  
Wet Weight

Annual production was estimated for five species of caddisflies and mayflies, comprising major components of the insect community, in the Redwood River, a second- to third-order plains stream in western Minnesota. Estmates were made at two sites, one above and one below an impoundment. At the upstream site, annual production (g∙m−2, wet weight) and annual P/B ratios (in parentheses) were Hydropsyche bifida, 8.3 (6.9); Cheumatopsyche pettiti, 5.5 (7.0); Stenonema nepotellum, 3.4 (5.7); Stenacron interpunctatum canadense, 0.8 (7.0); and Caenis simulans, 4.7 (4.2); with total annual production of 22.7 g∙m−2. At the downstream site, annual production and P/B ratios were H. bifida, 34.3 (4.4); C. pettiti, 68.5 (4.4); S. interpunctatum canadense, 24.1 (6.1); and C. simulans, 2.8 (4.4); with total annual production of 129.7 g∙m−2. These species comprised 27.5% of the total insect standing stock at the upstream site and 75.9% downstream. The hydropsychid production at the downstream site was apparently sustained by the drift of zooplankton from the impoundment, resulting in considerably higher production by hydropsychids than reported in woodland streams.Key words: production, Trichoptera, Ephemeroptera, plains stream, benthos, size–frequency method

Estimates of annual production for some aquatic insects from the La Trobe River, Victoria

1986 ◽  
Vol 37 (2) ◽  
pp. 113 ◽  
Author(s):  
R Marchant
Keyword(s):  
Aquatic Insects ◽  
Temperate Zone ◽  
Annual Production ◽  
Frequency Method ◽  
Habitat Temperature ◽  
Size Frequency ◽  
Total Annual Production ◽  
Annual Turnover

Annual production was estimated by the size-frequency method for Ephemeroptera (Tasmanocoenis tonnoiri, two species of Baetis, Atalonella spp., Atulophlebioides sp.), Plecoptera (Leptoperla spp.) and Trichoptera (Ecnomus sp.) at four sites on the lowland section of the La Trobe River. Annual production (P) of individual ephemeropteran species (or genera) varied from 0.02 to 0.7 g m-2 while total annual production of this order at two sites was 0.7-1 . 5 g m-. Annual production of Leptoperla spp. was 0.03 g m-2 at one site while Ecnomus sp, averaged 2 g m-2 at two sites. Estimates of annual production were subject to an error of at least t 50%. Annual turnover ratios (P/B; B is mean biomass) varied from 9 to 19 and were three to four times higher than published values for similar-sized macroinvertebrates in the temperate zone (generally < 15°C mean annual habitat temperature). This probably resulted from the higher average temperatures (17-18°C) at most sites.

Life spans of two species of tropical mayfly nymph (Ephemeroptera) from Magela Creek, Northern Territory

1982 ◽  
Vol 33 (1) ◽  
pp. 173 ◽  
Author(s):  
R Marchant
Keyword(s):  
Life Cycle ◽  
Life Span ◽  
Northern Territory ◽  
Annual Production ◽  
Length Frequency ◽  
Frequency Method ◽  
B Values ◽  
Size Frequency ◽  
Mayfly Nymph ◽  
Growth And Reproduction

The nymphs of Cloeon fuviatile and a species of Tasmanocoenis were common in the shallows (< 1 m) of two billabongs in Magela Creek, Northern Territory. Monthly estimates of abundance and length frequency showed that growth and reproduction occurred continuously. Estimates of the ratio of annual production to mean biomass (PIB) were calculated with the size-frequency method, using different values for nymphal life span; these estimates, when compared with P/B values predicted from the literature, suggested that the nymphs had a life span of about 1 month. Such a rapid life cycle is at least in part the result of the high mean temperature (30°C) in the shallows.

Production of the amphipod Hyalella azteca (Saussure) in a northern Ontario lake

1983 ◽  
Vol 61 (9) ◽  
pp. 2051-2059 ◽  
Author(s):  
Dorothy H. Lindeman ◽  
Walter T. Momot
Keyword(s):  
Littoral Zone ◽  
Lake Ontario ◽  
Hyalella Azteca ◽  
Dry Weight ◽  
Annual Production ◽  
Frequency Method ◽  
Northern Ontario ◽  
Habitat Temperature ◽  
Size Frequency ◽  
Annual Biomass

Annual production of the amphipod, Hyalella azteca, was estimated in three habitats of the upper littoral zone of Dock Lake, Ontario, over a 2-year period (1980–1981). Cohort production (P) by the size frequency method was 1.39 g/m2 (dry weight), mean annual biomass (B) was 0.36 g/m2, and the P/B ratio was 3.9 for the 1980 year class. Five other methods for estimating production were applied to this cohort, providing comparable estimates ranging from 1.21 (instantaneous growth) to 1.65 (cohort G) g/m2. Size frequency estimates of annual production for 1980 and 1981 were 1.24 and 1.40 g/m2, respectively. The annual P/[Formula: see text] ratios of 3.9 and 4.0 for these 2 years agree with the cohort value. A comparison of production estimates for Hyalella azteca in the literature shows a gradient of production which correlates with the habitat temperature regime.

Population and Production Dynamics of an Enchytraeid Worm in a Subtropical Blackwater River

1987 ◽  
Vol 44 (8) ◽  
pp. 1469-1474 ◽  
Author(s):  
David L. Stites
Keyword(s):  
Aquatic Insect ◽  
Dry Mass ◽  
Coarse Sand ◽  
Annual Production ◽  
Total Density ◽  
Frequency Method ◽  
Blackwater River ◽  
Size Frequency ◽  
Center Channel ◽  
Production Dynamics

Population and production dynamics of Barbidrilus paucisetus Loden and Locy (Oligochaeta: Enchytraeidae) in a sixth-order blackwater river are described. This worm was the dominant member of the meiofauna of the sand habitat, accounting for 50–90% of the total density. Population density varied seasonally, increasing from < 20 000/m2 in the winter to 60–120 000/m2 in the summer. Biomass averaged 145 mg dry mass/m2 with a range of 8–326 mg/m2. Density peaked in the clean coarse sand of the center channel areas and was lower where the sand was finer and where more organic matter was present. Size frequency histograms indicated that there were three recruitment peaks during the sampling year, with mature and new individuals present in all seasons. Annual production (2.12 g dry mass/m2, SE = 0.15 g/m2), was estimated using the size frequency method and a cohort production interval correction of 3. Annual production was low compared with that of terrestrial Enchytraeidae and comparable with that of many aquatic insect species. Annual production/biomass ratio (14.3) was higher than terrestrial Enchytraeidae, due to the comparatively short generation time of this species.

Use of the Size–Frequency (Hynes) Method to Estimate Annual Production of a Stream Fish Population

1983 ◽  
Vol 40 (11) ◽  
pp. 2030-2034 ◽  
Author(s):  
Greg C. Garman ◽  
Thomas F. Waters
Keyword(s):  
Salmo Trutta ◽  
Fish Population ◽  
Annual Production ◽  
Salmo Gairdneri ◽  
Frequency Method ◽  
Reliable Determination ◽  
Size Frequency ◽  
Production Values ◽  
Significant Difference

Previously developed and accepted methods of fish production estimation, such as instantaneous growth (G method), require aging of sampled individuals. Hynes' size–frequency method, however, does not require cohort separation. Annual production and approximate 95% confidence intervals are presented and compared for populations of brook, brown, and rainbow trout (Salvelinus fontinalis, Salmo trutta, and Salmo gairdneri) in Valley Creek, Minnesota, 1977–78, using the size–frequency and G methods. No significant difference was found between production values calculated by the two methods. It is proposed that the size–frequency method provides a reliable determination of annual production of fish populations and will be especially useful where accurate aging of individuals is not possible or where aging represents excessive labor.

Sources of Chlorophenolic Compounds to the Fraser River Estuary

1988 ◽  
Vol 23 (1) ◽  
pp. 55-68 ◽  
Author(s):  
J. H. Carey ◽  
J. H. Hart
Keyword(s):  
River Flow ◽  
River Estuary ◽  
Low Flow ◽  
Fraser River ◽  
Pulp Mills ◽  
Flow Conditions ◽  
Downstream Site ◽  
Upstream Site ◽  
The North ◽  
Main River

Abstract The identity and concentrations of chlorophenolic compounds in the Fraser River estuary were determined under conditions of high and low river flow at three sites: a site upstream from the trifurcation and at downstream sites for each main river arm. Major chlorophenolics present under both flow regimes were 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP), pentachlorophenol (PCP), tetrachloroguaiacol (TeCG) and a compound tentatively identified as 3,4,5-trichloroguaiacol (3,4,5-TCG). Under high flow conditions, concentrations of the guaiacols were higher than any of the Chlorophenols and concentrations of all five chlorophenolics appeared to correlate. Under low flow conditions, concentrations of chloroguaiacols were higher than Chlorophenols at the upstream site and at the downstream site on the Main Arm, whereas at the downstream site on the North Arm, concentrations of 2,3,4,6-TeCP and PCP were higher than the chloroguaiacols in some samples. Overall, the results indicate that pulp mills upstream from the estuary are important sources of chlorophenolics to the estuary under all flow conditions. Additional episodic inputs of 2,3,4,6-TeCP and PCP from lumber mills occur along the North Arm. When these inputs occur, they can cause the concentrations of Chlorophenols in the North Arm to exceed provisional objectives. If chloroguaiacols are included as part of the objective, concentrations of total chlorophenolics in water entering the estuary can approach and exceed these objectives, especially under low flow conditions.

scholarly journals Comparison of Antibiotic Resistance Profile of Escherichia coli between Pristine and Human-Impacted Sites in a River

Antibiotics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 575
Author(s):  
Emi Nishimura ◽  
Masateru Nishiyama ◽  
Kei Nukazawa ◽  
Yoshihiro Suzuki
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Resistance ◽  
Resistant Bacteria ◽  
Downstream Site ◽  
Antibiotic Resistant Bacteria ◽  
Antibiotic Resistant ◽  
Upstream Site ◽  
Resistance Profile ◽  
Antibiotic Resistance Profile ◽  
Significant Difference

Information on the actual existence of antibiotic-resistant bacteria in rivers where sewage, urban wastewater, and livestock wastewater do not load is essential to prevent the spread of antibiotic-resistant bacteria in water environments. This study compared the antibiotic resistance profile of Escherichia coli upstream and downstream of human habitation. The survey was conducted in the summer, winter, and spring seasons. Resistance to one or more antibiotics at upstream and downstream sites was on average 18% and 20%, respectively, and no significant difference was observed between the survey sites. The resistance rates at the upstream site (total of 98 isolated strains) to each antibiotic were cefazolin 17%, tetracycline 12%, and ampicillin 8%, in descending order. Conversely, for the downstream site (total of 89 isolated strains), the rates were ampicillin 16%, cefazolin 16%, and tetracycline 1% in descending order. The resistance rate of tetracycline in the downstream site was significantly lower than that of the upstream site. Furthermore, phylogenetic analysis revealed that many strains showed different resistance profiles even in the same cluster of the Pulsed-Field Gel Electrophoresis (PFGE) pattern. Moreover, the resistance profiles differed in the same cluster of the upstream and the downstream sites. In flowing from the upstream to the downstream site, it is plausible that E. coli transmitted or lacked the antibiotic resistance gene.

scholarly journals Niche Differentiation of Active Methane-Oxidizing Bacteria in Estuarine Mangrove Forest Soils in Taiwan

2020 ◽  
Vol 8 (8) ◽  
pp. 1248
Author(s):  
Yo-Jin Shiau ◽  
Chiao-Wen Lin ◽  
Yuanfeng Cai ◽  
Zhongjun Jia ◽  
Yu-Te Lin ◽  
...  
Keyword(s):  
Plant Biomass ◽  
Niche Differentiation ◽  
Stable Isotope Probing ◽  
Field Conditions ◽  
Type I ◽  
Mangrove Forests ◽  
Downstream Site ◽  
Upstream Site ◽  
Type Ia ◽  
Mangrove Soils

Mangrove forests are one of the important ecosystems in tropical coasts because of their high primary production, which they sustain by sequestering a substantial amount of CO2 into plant biomass. These forests often experience various levels of inundation and play an important role in CH4 emissions, but the taxonomy of methanotrophs in these systems remains poorly understood. In this study, DNA-based stable isotope probing showed significant niche differentiation in active aerobic methanotrophs in response to niche differentiation in upstream and downstream mangrove soils of the Tamsui estuary in northwestern Taiwan, in which salinity levels differ between winter and summer. Methylobacter and Methylomicrobium-like Type I methanotrophs dominated methane-oxidizing communities in the field conditions and were significantly 13C-labeled in both upstream and downstream sites, while Methylobacter were well adapted to high salinity and low temperature. The Type II methanotroph Methylocystis comprised only 10–15% of all the methane oxidizers in the upstream site but less than 5% at the downstream site under field conditions. 13C-DNA levels in Methylocystis were significantly lower than those in Type I methanotrophs, while phylogenetic analysis further revealed the presence of novel methane oxidizers that are phylogenetically distantly related to Type Ia in fresh and incubated soils at a downstream site. These results suggest that Type I methanotrophs display niche differentiation associated with environmental differences between upstream and downstream mangrove soils.

Regrowth of smooth bromegrass (Bromus inermis Leyss.) following defoliation

1994 ◽  
Vol 74 (3) ◽  
pp. 531-537 ◽  
Author(s):  
T. Harrison ◽  
J. T. Romo
Keyword(s):  
Vegetative Growth ◽  
Early Spring ◽  
Bromus Inermis ◽  
Annual Production ◽  
Growth Stages ◽  
Forage Production ◽  
Smooth Bromegrass ◽  
Total Annual Production ◽  
Growing Conditions ◽  
Reproductive Phases

Regrowth and production of tillers in smooth bromegrass (Bromus inermis Leyss.) following defoliation to a 5-cm stubble height were monitored throughout the summer and in early spring the following year in central Saskatchewan. After defoliation, while smooth bromegrass was vegetative, forage began accumulating in 45–75 growingdegree-days (GDD) when moisture was favorable. Regrowth ranged from 34 to 84 g m−2. Plants also produced ≤ 51 g m−2 of regrowth when defoliated at or before culm elongation in a year with above-average precipitation. In two dry years, regrowth was minimal and plants did not regrow after defoliation in the later vegetative growth stages; however, new leaves were produced within 110–140 GDD. Following defoliation at early vegetative growth stages, 1030–1180 GDD were needed to reach maximum regrowth. Total annual production was either unaffected or reduced by defoliation. Total annual production ranged from 35 to 139 g m−2, with yields lowest when defoliated in early May or early June and highest when herbage was removed in mid-May or near flowering and seed production. When plants were defoliated during vegetative growth most tillers were produced the following spring, whereas when plants were defoliated during reproductive phases the majority of tillers emerged in the fall. The year after defoliation, the density of tillers (871–951 m−2) was not significantly different among treatments. Regrowth following defoliation cannot be related to a particular growth stage, but rather it depends on growing conditions. If smooth bromegrass is defoliated once and rested until the next year, it should be recovered by early spring and its productivity should be unaffected. Key words: Etiolated growth, forage production, grazing management, regrowth, rest requirement, tillering

Production of Chironomus, Procladius, and Chaoborus at Different Levels of Phytoplankton Biomass in Lake Memphremagog, Quebec–Vermont

1977 ◽  
Vol 34 (11) ◽  
pp. 2001-2007 ◽  
Author(s):  
R. M. Dermott ◽  
J. Kalff ◽  
W. C. Leggett ◽  
J. Spence
Keyword(s):  
Phytoplankton Biomass ◽  
Standing Stock ◽  
Dry Weight ◽  
Annual Production ◽  
The South ◽  
Algal Production ◽  
The North ◽  
Chaoborus Punctipennis ◽  
The Mean ◽  
Different Levels

In Lake Memphremagog a north–south gradient in algal production and biomass exists during the ice-free period, with highest production in the southern areas. In response, the mean annual benthic standing stock (dry weight) in the south basin was 2.8 times greater than in the north basin at comparable depth. Mean annual standing stock of Procladius denticulatus and Chironomus anthracinus were significantly (5.8 and 3.1 times, respectively) higher in the south, while that of Chaoborus punctipennus did not differ significantly between areas. Annual production of P. denticulatus was greater in the south (0.861 g/m2) than in the north (0.143 g/m2). Similarly for Chironomus anthracinus annual production was greater in the south (3.393 g/m2) than in the north (1.264 g/m2). Production of Chaoborus punctipennis was greater in the north (0.066 g/m2) than in the south (0.348 g/m2). P:B ratios were less variable. Key words: Lake Memphremagog, benthos, production, nutrient gradient, mortality

Sign in / Sign up

Export Citation Format

Share Document