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1.
A family of pneumatically-operated thin layer samplers for replicate sampling of heterogeneous water columns 总被引:1,自引:1,他引:0
A series of inexpensive, pneumatic thin layer water samplers is described. They can be operated from small boats, and permit sampling at 2.5 cm intervals with little or no disturbance of stratified systems such as oxyclines or redoxclines of meromictic lakes, or microstratification of flagellates in sheltered epilimnia. Some models permit replicate sampling at closely-spaced intervals in a two-dimensional array. Their performance abilities are illustrated with examples of microstratification. 相似文献
2.
A hand-operated water sampler designed specifically for dissolved gas studies in lakes, lagoons and other shallow water is described. 相似文献
3.
INGGARD ARNE BLAKAR 《Freshwater Biology》1978,8(6):533-537
SUMMARY. A lightweight, free-flushing water and plankton sampler constructed of readily available, inexpensive material is described. Easily interchangeable tubes of varying volumes allow sampling flexibility. The sampler is activated by a messenger and is shut by two plastic funnels. For analyses in highly stratified waters, the sampler can be adjusted into the horizontal position. Several samplers may be tripped in series. The sampler has proved a versatile and reliable instrument in ecological studies.
The tripping mechanism may also be used to release reversing thermometers and closing nets. 相似文献
The tripping mechanism may also be used to release reversing thermometers and closing nets. 相似文献
4.
An instrument was designed which facilitates faster and more accurate sampling of leaf discs for psychrometric water potential measurements. The instrument consists of an aluminum housing, a spring-loaded plunger, and a modified brass-plated cork borer. The leaf-disc sampler was compared with the conventional method of sampling discs for measurement of leaf water potential with thermocouple psychrometers on a range of plant material including Gossypium hirsutum L., Zea mays L., and Begonia rex-cultorum L. The new sampler permitted a leaf disc to be excised and inserted into the psychrometer sample chamber in less than 7 seconds, which was more than twice as fast as the conventional method. This resulted in more accurate determinations of leaf water potential due to reduced evaporative water losses. The leaf-disc sampler also significantly reduced sample variability between individual measurements. This instrument can be used for many other laboratory and field measurements that necessitate leaf disc sampling. 相似文献
5.
The construction and operation of a hand-operated box sampler is described. The sampler covers an area of 25 × 25 cm and penetrates into the sediment to the depth of 15 cm. It was successfully operated on a sandy bottom, and on sand mixed with gravel up to a water depth of 1 meter.IAEC, Yavne 70600, Israel 相似文献
6.
P. D. Armitage 《Hydrobiologia》1979,66(3):245-248
A new easily retrieved folding artificial substratum sampler is described and its performance compared with that of trays in Cow Green Reservoir at a depth of 15–18 m. 相似文献
7.
An inexpensive, easily constructed apparatus for collecting interstitial water from sandy substrates is described and evaluated against two other devices. Results indicate that these samplers yield comparable dissolved oxygen determinations, but vary in terms of repeatability, efficiency, construction complexity and sturdiness. 相似文献
8.
The segmented integrating pipe sampler (SIPS) samples a continuousvertical profile of physical and biological properties of theupper water column. Composite or detailed samples can be collectedfor analysis of phytoplankton abundance and distribution. Thissampling system requires no power source and can be operatedfrom a small boat or platform in a variety of aquatic habitats.The correlation coefficient calculated for the phytoplanktonabundance sampled by the SIPS and pump was 0.900, while thecoefficient for the SIPS and Niskin bottle comparison was 0.797. 相似文献
9.
SUMMARY. Details are presented for the construction and operation of a cheap simple volume sampler for Zooplankton and water. This sampler has been used in waters up to 45 m deep over a number of years and proved to be reliable and effective. 相似文献
10.
A large volume water sampler which can enclose, at any givendepth, a body of relatively undisturbed water including organismsis described. Its functioning and some results of sampling atsea are given. 相似文献
11.
Roger Jones 《Hydrobiologia》1975,47(3-4):431-437
A freshwater sampler using five sterile evacuated glass tubes is described. Water enters when a rubber stopper is mechanically removed from the end of a sterile hypodermic needle inserted into each tube. Plate counts of bacterial colonies were compared with those obtained with other samplers. 相似文献
12.
A microgradient sampler for shallow waters 总被引:1,自引:0,他引:1
A. G. A. Merks 《Aquatic Ecology》1979,13(1):61-67
Summary A cheap, light and simple device is described for the sampling of physico-chemical microgradients in the free-water zone of shallow water bodies. The sampler is commercialized by ATS, Mariastraat 42, The Hague, The Netherlands.Publication no. 179 of the Delta Institute for Hydrobiological Research. 相似文献
13.
Ken'ichi Satake 《Hydrobiologia》1992,232(2):149-156
A handy sampler for collecting water from lakes, rivers and seas is described. The sampler consists of an exchangeable sample tube and a new sample-holding system. The system comprises an upper disk, a lower disk, a pair of arms with a guide pin and a semicircular arm guide with a groove. The water sample collected into the acryl tube is held without flow by a tight tube-closing system. Contamination of the sample by chemical and biological materials from the sample tube is minimized by exchanging the tube with a clean one at each sampling station. This new sampler is light, simple and useful for sampling of water from surface to bottom. 相似文献
14.
R. L. Kitching 《Hydrobiologia》1971,37(2):205-209
Summary A core sampler developed for use in sampling water-filled tree-holes is described. This apparatus consists of an auger mechanism that fits inside the conventional corer tube. Its construction is simple and inexpensive and the resulting instrument is both portable and easy to use. Resumen Una descripción de un tubo saca-testigos dise?ado para tomar muestras en cavidades de árboles conteniendo agua es presentada. El aparato consiste de un mecanismo taladrante que se ajusta dentro del tubo del saca-testigos convencional. Su construcción es simple y barata, y el instrumento es portátil y fácil de usar. 相似文献
15.
A quantitative sampler for air-breathing aquatic insects 总被引:1,自引:0,他引:1
SUMMARY. A quantitative funnel-trap sampler for air-breathing aquatic insects is described. Performance tests with special reference to adult Glaenocorisa propinqua are presented. Abundance was calculated from pilot surveys with the funnel-trap sampler during 1976 and compared with results from a trial with the capture-recapture method. The influence of temperature on the frequency with which adult Glaenocorisa propinqua renews the bubble gilt was measured. 相似文献
16.
Summary 1. A fully portable suction sampler which can be operated by one diver is described.2. Rock epibiota is removed by a scraper tube which leads, through a collecting chamber, to an air-lift suction chamber and tube. The sample is held in a net bag before reaching the suction chamber. Air is supplied by a cylinder incorporated into the unit.3. The sampler removes all epilithic biota except for the parts of encrusting species cemented to the rock.4. The sampler can also be used for sand fauna.
Ein tragbarer Saugsammler für epibiotisch auf Felsen lebende Organismen
Kurzfassung Eine Saugpumpe für bestandskundliche Untersuchungen, die von einem Taucher getragen und bedient werden kann, wird beschrieben. Sie besteht aus einer Sammelkammer, in die zwischen dem Schabrohr und der Luftsaugkammer ein Sammelnetz eingefügt wird. Die Saugkammer ist durch ein Reduktionsventil mit einem Preßluftzylinder verbunden. Mit Hilfe dieses Sammelgeräts lassen sich fast alle Organismen von Felsoberflächen entfernen. Es kann überdies auch zur quantitativen Erfassung der Fauna auf Sandböden eingesetzt werden. Vor- und Nachteile dieses Gerätes werden diskutiert.相似文献
17.
A sampling technique for collecting lotic periphyton on sedimentary substrates using a peristaltic pump is described. Quantitative samples of periphyton standing crop and colonization rate are collected by the same procedure. The technique eliminates human disturbance problems associated with floating artificial samplers by establishing permanent sampling sites directly on submerged substances. 相似文献
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Summary 1. A new bottom sampler for macrofauna is described which is easily operated by a diver.2. The airlift pump principle is employed firstly to sink a sampling cylinder into the seabed and secondly to operate a suction pipe which is used to excavate sand and animals from within the cylinder.3. The sampler covers an area of 0.1 m2 and penetrates to a depth of 60 cm. It is particularly suitable for quantitative studies of deeper burrowing fauna (e. g.Ensis spp. andLutraria spp.).4. The sampler is designed for use in sandy sediments and for studies on the distribution of faunas within small areas where line transects or grids of samples are required.
Ein vom Taucher betätigtes Gerät zur quantitativen Entnahme der Makrofauna auf Sandböden
Kurzfassung Zur Entnahme quantitativer Proben der Makrofauna aus festem Sandboden gibt es nur zwei Geräte, die beide sehr schwer sind und einer kräftigen Winde auf einem großen Schiff bedürfen: (a) der Knudsengreifer (0,1 m2 Fläche, 30 cm Einstichtiefe, 150 kg) und (b) der Kastengreifer von Reineck (20×30 cm Fläche, 40 cm Einstichtiefe, 750 kg). Für Untersuchungen über die Verteilung benthischer Makrofauna innerhalb kleiner Gebiete war jedoch ein Gerät zur Entnahme von Bodenproben erwünscht, das von einem Taucher gezielt eingesetzt werden kann. Eine Sammeltiefe von mehr als 30 beziehungsweise 40 cm war erforderlich, um den Fang der tiefer grabenden Arten, beispielsweise der MuschelLutraria, zu gewährleisten. Das neue Gerät wurde zweiteilig entworfen. Der eine Teil besteht aus einem offenen Stahlzylinder, der eine Länge von 60 cm und eine Grundfläche von 0,1 m2 aufweist. Er wird zunächst mit Handkraft senkrecht in den Boden hineingepreßt, damit er vom Sand gut abgedichtet wird. Das obere Ende wird anschließend mit einem Deckel verschlossen, und das Wasser, das sich im Zylinder oberhalb des Sedimentes befindet, wird durch eine Pumpe abgesogen. Der hydrostatische Druck auf den Deckel preßt den Zylinder in den Sand. Wenn der Zylinder völlig in das Sediment versenkt ist, wird der Deckel entfernt und der vom Zylinder umfaßte Sand durch den zweiten Teil des Gerätes ausgesaugt. Dieser besteht aus einer langen Kunststoffröhre von etwa 8 bis 10 cm Durchmesser. Sie wird in senkrechter Stellung völlig unter Wasser gehalten. Wird Luft unter Druck in das untere Ende eingeleitet, so funktioniert die Röhre als eine Lufthebepumpe. Ein speziell gebautes Sieb ist am oberen Ende des Steigrohres befestigt. Der Taucher führt das untere Ende dieser Saugpumpe in den Zylinder und saugt dessen Inhalt in das Sieb hinein. Die Druckluft für die Betätigung des Instrumentes wird von einem Kompressor oder aus Druckluftflaschen (4–5 m3) geliefert. Das beschriebene Gerät ist leicht und kann deshalb mühelos vom Taucher bedient werden. Es kann von Kleinbooten aus eingesetzt werden und benötigt keine Winde.相似文献