База резюме и ссылок по экологии бентоса

Двукрылые: хирономиды в меловом ручье.

Chironomid community structure deduced from larvae and pupal exuviae of a

chalk stream.

Hydrobiologia 315(2). 1995. 135-142.

Species abundances of Chironomidae (Insecta: Diptera) have often been

excluded from studies of benthic river communities because of difficulties

associated with sampling and identifying larvae. Chironomid pupal exuviae

are easier to collect and identify and could be used to determine

community structure if shown to be representative of local larval

assemblages. Larvae were sampled along a 20 m chain secured over

mid-channel gravels, upstream of two collection points for pupal exuviae.

Proportional taxa abundances of pupal exuviae and larvae sampled from 130

m of stream were directly compared by a chi-2 test of independence and

also separately fitted to four models of species abundance distribution.

Observed proportions of taxa were not independent of the life stage

sampled. The greatest discrepancies occurred with species of pupal exuviae

that were absent as larvae from the gravel. The log series model provided

the best fit with both pupal and larval data. Collections of pupal exuviae

had greater species richness and evenness than samples of larvae. This was

considered to be a consequence of sampling larvae from the gravel habitat

alone.

Двукрылые: хирономиды морской литорали, Канада.

Institution

Dep. Biol., Memorial Univ., St. John's, Newfoundland A1B 3X9, Canada.

Chironomidae from marine coastal environments near St. John's,

Newfoundland, Canada.

Hydrobiologia 318(1-2). 1996. 117-122.

Chironomid larvae and adults were collected from rock pool and intertidal

sites between 1990 and 1994 on the exposed Atlantic coast and in more

sheltered bays near St. John's. From several thousand specimens collected,

16 chironomid taxa were identified. Two were from intertidal habitats and

the remainder occurred in rock pools. In intertidal habitats Halocladius

variabilis was abundant in summer among clumps of fine filamentous algae,

e.g. Pilayella littoralis. The previous Nearctic records of this

chironomid were from Hudson Bay and Greenland although it is widespread in

northern Europe. The other intertidal species, Telmatogeton japonicus, was

recorded from one site, a rock outcrop on a beach in the mouth of a small

stream. This Holarctic species has not been reported previously north of

New York on the Atlantic coast. The rock-pool communities were dominated

by Psectotanypus dyari, Cricotopus sylvestris, Psectocladius sordidellus

gp, Orthocladius dubitatus, Chironomus riparius, and Tanytarsus sp. These

taxa are known to tolerate sites with elevated salinity and/or

conductivity and thus are present in polluted sites inland. The other

eight chironomid species were rare and most were found at only one site.

An exception was the Metriocnemus sp. collected in very low numbers at

three sites and also collected previously during a survey of rock pools

for larval mosquitoes in the same area. The current study shows that a

diverse coastal chironomid community is present in the cold ocean habitats

of eastern Newfoundland. The community is made up of both arctic and

temperate faunal elements with widespread distributions not confined to

coastal habitats. Ranges of temperature, salinity, conductivity and pH for

the common species occurring in the rock pools are provided. The results

suggest that coastal rock pool habitats could be a natural laboratory for

studies on the evolutionary ecology of pollution tolerance in chironomids.

Двукрылые: питание Tipula.

Food value of introduced eucalypt leaves for a Mediterranean stream detritivore: Tipula lateralis.

Freshwater Biology 34(2). 1995. 209-214.

1. Food preference, consumption and growth of Tipula lateralis feeding on

leaves of one exotic (Eucalyptus globulus) and three native trees of

central Portugal (Alnus glutinosa, Castanea sativa and Quercus faginea)

were investigated. 2. Larvae preferred and consumed more alder than the

other three species. Larvae fed oak and eucalyptus did not grow, while

those fed alder had a faster mean specific growth than those fed chestnut.

Alder also provided a higher and earlier peak growth rate, which occurred

at 35 days vs. 91 days for chestnut. 3. High values of survivorship to 126

days were observed in larvae fed alder and chestnut. All larvae fed oak

died within 63 days; those fed eucalyptus died within 91 days. 4. Leaf

utilization by Tipula lateralis seems to be negatively correlated with

cuticle thickness and polyphenolic content and positively correlated with

microbial colonization and nutrient content of the leaves. We hypothesize

that the replacement of the original deciduous forest by eucalyptus

plantations may induce deleterious changes in the associated invertebrate

communities and stream ecosystem processes.

Двукрылые

Life history variability of a grazing stream insect (Liponeura cinerascens minor; Diptera: Blephariceridae)

Andreas Frutiger and Gabriella Meier Buergisser

SUMMARY1.Fourteen populations of Liponeura cinerascens minor from different

sites in the Swiss Alps were investigated. Our goals were to describe the life history

of this blepharicerid species and to analyse how it was influenced by temperature

and food availability.

2.Temperature regimes and periphyton density at the sampling sites varied

considerably. Mean annual temperature ranged from 3.8 to 6.5°C, with annual

amplitudes (i.e. the difference between the mean of the coldest and the warmest

month) between 3.7 and 12.0°C. Averaged periphyton density, which was assessed

semiquantitatively on a scale from 0 to 5, ranged from 1.1 to 3.3.

3.Larvae or pupae of L. c. minor were found between January and October.

Presence of larvae or pupae at individual sites ranged from 100 to 224days and

appeared to be mainly a result of hatching patterns. Individual larval development

required between 7 and 20weeks. Our findings suggest that L. c. minor is univoltine

and undergoes an extended (=" border=0

src="/na102/home/ACS/journals/entities/2265.png"4months) egg dormancy during

late summer, autumn and winter.

4.Development of L. c. minor was observed from <1 to 15.8°C, indicating it is a

cold-stenotherm. Its geographical distribution seems to be constrained by high

summer temperatures. Within the tolerated temperature range (0-16°C), however,

temperature had no apparent effect on hatching, larval growth rate or pupal size.

5.Larval growth rate and size of pupae were significantly correlated with food

availability. Completion of larval development required 300-400degree-days at sites

where periphyton was readily available, but >800degree-days where periphyton

availability was low.

6.No evidence for intraspecific food competition was found, whereas food

competition by other blepharicerid species, mainly Hapalothrix lugubris, appeared

to be a major reason for the observed food limitation. However, as L. c. minor is

much more widespread than H. lugubris, food competition between these two

species is likely to occur infrequently. We therefore contend that variations in the

life history of L. c. minor are mainly a consequence of its thermal constraints.

Двукрылые: Simuliidae, колонизация.

Stream Insects (Austrosimulium-spp) Following Disturbance

Source: FRESHWATER BIOLOGY

1991, Vol 26, Iss 2, pp 295-306

Language: English

Document type: Article

Addresses:

MONASH-UNIV, CTR STREAM ECOL, DEPT ECOL & EVOLUT BIOL,

CLAYTON, VIC 3168, AUSTRALIA

Keywords Plus:

PATCH DYNAMICS; ACHERON RIVER; MACROINVERTEBRATES; ECOLOGY;

STONES; PHYTOPLANKTON; SYSTEMS; ALGAE

Abstract:

1. In many streams, blackfly larvae rapidly colonize

scoured surfaces, then decline in numbers as other species are

still increasing. Such a colonization pattern may be generated

by species that seek disturbed substrata because they prefer

scoured surfaces having low epilithon cover (i.e. they are

opportunists) or because of lowered faunal densities (i.e. they

are fugitives), but this has rarely been tested.

2. In the Acheron River, south-eastern Australia, the

larvae of the blackfly Austrosimulium torrentium show the

typical pattern of increase and decline whereas A. victoriae

shows a different pattern of more gradual increase.

3. An experiment showed that A. torrentium, consistent

with its colonization pattern, responded strongly to treatments

that mimicked the effects of disturbance; it colonized bricks

with few other animals present regardless of epilithon cover and

therefore is potentially a fugitive species. A. victoriae did

not respond convincingly to treatments, which is also consistent

with its colonization pattern.

4. Blackfly larvae of both species preferentially

colonized bricks that were in fast-moving water. Hence, A.

torrentium only responded to the densities of other fauna when

bricks occurred in currents greater than approximately 30 cm s-

1.

5. Whilst epilithon cover did not affect abundance of

experimental treatment, epilithon was reduced on one half of the

top surfaces of bricks. More than 50% of larvae on these bricks

were attached to the epilithon-reduced halves.

6. Our results show that functional feeding or taxonomic

groups do not necessarily contain ecologically equivalent taxa;

colonization patterns may provide a more useful way of

categorizing species for the purposes of modelling these

assemblages.

Двукрылые: Simuliidae, распределение.

Title: Diversity, Distribution and Seasonality of the

Simuliidae Fauna in a Glacial Stream System in the Swiss

Alps

2001, Vol 152, Iss 1, pp 19-37

Spatial and seasonal patterns in the densities and species

richness of Simuliidae (blackflies) were examined in the glacier-

fed Roseg River, Switzerland. We also investigated how selected

environmental factors were related to the observed community

structure. Overall, 7 blackfly species were found in streams of

this glacial flood plain. Total densities and species richness

differed significantly among sampling dates, and densities

showed a significant downstream increase. Non-metric

multidimensional scaling supported these findings and suggested

that seasonal changes were affected strongly by extent of

glacial influence. Furthermore, our results were indicative that

spatio-temporal habitat heterogeneity ameliorated the negative

effects of high discharge conditions in summer. This resulted in

enhanced overall ecosystem stability in this glacier-fed stream

ecosystem, and enabled biotic assemblages to sustain populations

under the harsh environmental conditions experienced at this

time of the year. Low temperatures and channel instability

limited Simuliidae colonization close to the glacier terminus.

Suspended particles represented the most important food source

for simuliids in the Roseg River.

Двукрылые: мошки.

Volume 42 Issue 2 Page 301 - September 1999

Diversity, distribution and larval habitats of North Swedish blackflies (Diptera: Simuliidae)

Bjorn Malmqvist* and Yixin Zhang* and Peter H. Adler

1.Blackfly species richness and community structure were analysed at fifty-six sites

in northern Sweden in two seasons. The sites were situated in a wide range of

streams and rivers from small springbrooks, bog streams and lake-outlet streams to

medium-sized forest rivers and large rivers draining montane regions.

2.Thirty-nine blackfly species were found, with between two and thirteen species

per site. Neither species richness nor abundance could be related to the

environmental variables measured.

3.An analysis of labral fan size of blackflies indicated a clear trend for the

prevalence of larvae with small fans in large rivers and larvae with larger fan size in

small streams. Similarly, fan size related to current velocities so that large fans were

associated with slow current velocities and small fans with high velocities.

4.A strong relationship existed between species composition and habitat, as seen in

ordination by non-metric multidimensional scaling. The relationship found between

fan size and habitat size-related variables, such as channel width, depth, velocity

and substratum particle size, along with longitude and altitude, in partial least

squares regression analysis offered an explanation of the species composition-

habitat relationship.

5.In addition to testing that distributions of blackfly larvae reflect morphological

traits, we tested two general hypotheses pertaining to distribution patterns: (a) that

blackfly communities show bimodal distributions; and (b) that their distributions are

nested. Neither of these two hypotheses was supported by our observations.

However, widespread blackfly species were locally more abundant than those

found at relatively few sites, thus showing a positive abundance-occupancy

relationship.

Двукрылые: мошки, Швейцария.

02.03-04А2.124. Разнообразие, распределение и сезонная динамика фауны Simuliidae в системе ледниковой реки в Швейцарских Альпах. Diversity, distribution and seasonality of the Simuliidae fauna in a glacial stream system in the Swiss Alps / Burgherr Peter, Ward J.V., Glatthaar Rolf // Arch. Hydrobiol. - 2001. - 152, № 1. - С. 19_ѕ37. - Англ.

Изучали плотность и видовое богатство Simuliidae в реке с ледниковым питанием. Отмечено 7 видов мошек, плотность к-рых возрастала вниз по течению. Наблюдаемые сезонные изменения связаны с влиянием ледника. Показано, что гетерогенность биотопов смягчает отрицательное влияние повышенного расхода воды в летнее время в период таяния ледника. Это проявляется в повышении стабильности экосистемы реки с ледниковым питанием и делает возможным существование популяций при ухудшении условий существования. На границе с ледником колонизация Simuliidae затруднена из-за низкой т-ры и нестабильности русла. Основную пищу представляют собой взвешенные частицы. Швейцария, Paul Scherrer Institut, 5232 Villigen PSI, E-mail: peter.burgherr@psi.ch. Ил. 3. Табл. 3. Библ. 50.

Двукрылые: Empididae, распределение в водотоке.

Wagner R. Gathmann O.

Institution

Limnologische Flussstation des Max-Planck-Instituts fuer Limnologie, P.O.

Box 260, D-36105 Schlitz, Germany.

Title

Long-term studies on aquatic dance flies (Diptera, Empididae) 1983-1993:

Distribution and size patterns along the stream, abundance changes between

years and the influence of environmental factors on the community.

Source

Archiv Fuer Hydrobiologie 137(3). 1996. 385-410.

Twenty nine species of aquatic dance flies (Empididae: Clinocerinae and

Hemerodromiinae) were recorded from the Breitenbach (Hesse, Germany)

between 1983 and 1993. Although most species emerged in spring and summer,

Clinocera (Hydrodromia) stagnalis and C. (H.) wesmaeli were trapped in

almost every month. A few species of the subgenus Kowarzia of Clinocera

emerged in autumn and early winter. Chelifera pyrenaica had two

generations per year in the lower part of the stream, but in the upper

reach there was only a spring generation. The distribution pattern along

the stream of most of the abundant species was maintained over the entire

study period. As an exception, Wiedemannia bohemani was abundant in the

middle reach of the stream between 1983-1988, but in the lower reach in

1989-1993. As the amount of Particulate Organic Matter (POM) probably

increased the abundance of prey organisms, highest numbers were found in

areas with high amounts of allochthonous input. Larvae avoided sandy

substrates. Many were found in partly submerged moss carpets on stones, at

or below the water level. Females of Hemerodromiinae had higher body

weights than males, and specimens in localities near the spring were

heavier than those from lower sections of the stream, probably as a result

of the temperature pattern of the stream. In Clinocerinae the differences

between the sexes, and at different sites, were negligible. Ordination of

abundance data, as well as environmental data, showed the dominating

influence of 'time' and discharge pattern on the community of aquatic

dance flies, and the subordinate influence of water temperature, in a time

series of 11 years.

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