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Understanding Coral Reefs

Tights01vito — Tue, 19 Mar 2013 04:13:19 GMT

Tights01vito: Die Seite wurde neu angelegt: „[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/introduction-to-the-underwater-world/ What Are Coral Reefs] - Introduction to the Underwater World [http://…“

[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/introduction-to-the-underwater-world/ What Are Coral Reefs] - Introduction to the Underwater World
[http://blog.stevenwsmeltzer.com/what-are-coral-reefs/ Coral reef systems] consist of tiny animals that are in the class anthozoans, the major class of organisms within the phylum cnidaria (the "c" is silent). Cnidaria has greater than 6,000 identified species of sea fans, sea pansies, jellyfish, and sea anemones. Corals, after their larvae phase, no longer move but are fixed in one place. This type of animal is called a sessile animal.

[http://www.stevenwsmeltzer.com Coral reef] colonies are made of millions of these very small, cup-shaped animals known as polyps. A solitary coral polyp might be as big as a saucer or smaller than the head of a pin. Millions of polyps functioning in concert in a collaborative colony over many years make the limestone skeletons that create the framework of the wonderful coral reef. Coral reef colonies reproduce both sexually and asexually. In sexual reproduction, the coral polyps release both eggs and sperm into the water. (This is also known as coral spawning.) One kind of asexual reproduction occurs when fragments of coral are broken off because of a storm. The broken pieces of corals typically live and continue to grow and produce a new colony. This method is known as "fragmentation". Corals exist in colonies consisting of numerous individuals, each of which is called polyp. They produce a hard calcium carbonate (rock-like) skeleton, which serves as a uniform base or substrate for the colony. This skeleton enables two fundamental functions, first for the coral itself it offers safety, as the polyps can contract into the structure if predators draw near and second this same skeletal structure is what creates the coral reefs over a period of time. The calcium carbonate is secreted at the bottom of the polyps, consequently the living part of the coral colony occurs at the exterior of the skeletal structure, totally covering it. The calcium carbonate created by the living colony continually adds to the size of the overall structure and therefore the expansion of the coral reef. The growth of these reef structures varies greatly, based on the varieties of coral and environmental conditions-- ranging from 0.3 to 10 centimeters per year. The skeletons of stony corals are produced by the lower portion of the polyp. This method creates a cup, called the calice, in which the polyp sits. The walls surrounding the cup are called the theca, and the floor is known as the basal plate. Thin, calcareous septa (sclerosepta), which provide structural integrity, protection, and an increased surface area for the polyp's soft tissues, extend upward from the basal plate and radiate inward coming from its outer wall. From time to time, a polyp will lift off its base and produce a new floor to its cup, forming a new basal plate just above the old one. This creates a minute chamber in the skeleton. When polyps are physically stressed or under potential attack, they contract into the calice so that virtually no part is exposed above the skeletal platform. This protects the creature from predators and the elements (Barnes, R.D., 1987; Sumich, 1996). Different varieties of coral construct structures of various dimensions and shapes such as brain corals, fan corals, encrusting corals, etc., creating marvelous variety and complexity in the coral reef ecosystem. Various coral varieties tend to be segregated into characteristic zones on a reef, separated out by competition with other species along with environmental conditions. Corals contain only a narrow degree of organ development and consists of three fundamental tissue layers: an external layer or epidermis, an inner layer of cells lining the gastrovascular cavity (an internal space for digestion) and a layer called the mesoglea between the other two layers Barnes, R.D., 1987. Corals feed by reaching out by means of tentacles to seize prey such as small fish and planktonic creatures (any drifting organisms, animal, plant, archaea or bacteria that inhabit the pelagic zone of the oceans). See Also: Creatures of the Coral Reefs Resources: Marine Species Galleries: Coral Reef Images Pictures of Fish Sea Turtles Crustaceans and Echinoderms Moray Eels Detailed Information on select Marine Species: Caribbean Fish Hawaiian Fish Sponges Crustaceans, Invertebrates, Mollusks, Echinoderms

Best Compact Digital Waterproof Cameras

Tights01vito — Sun, 17 Mar 2013 20:11:01 GMT

Tights01vito: Die Seite wurde neu angelegt: „When considering waterproof point and shoot cameras lens speed or the "f-stop" rating. The faster the lens., e.g., the lower the f-stop number the better and the …“

When considering waterproof point and shoot cameras lens speed or the "f-stop" rating. The faster the lens., e.g., the lower the f-stop number the better and the more light which the lens allows into the camera making for superior quality, less noise images. f2.0 is very fast and f3.9 is ok, but it will have more difficulty in lower light situations and will generally be a little more hard to focus in reduced light situations. A different characteristic is the capability of the zoom lens and how much of the "zoom" is produced by the lens versus a digital zoom, where software is creating the zooming effect. One more feature for shooting close up is the capability to take macro photos and how close to the subject matter you can get the camera and still focus. One additional feature to consider would be the ability to shoot video and the video processors speed, e.g., does the camera have a high speed video processor meaning it will capture in excess of 200 frames per second (fps), or else does it have a low speed video processor. A faster vidwo processor will create higher quality videos.

The reviews of the cameras listed below gives a good quality overview of a number of of the best point and shoot waterproof cameras along with a suggestion on the best camera.

Waterproof cameras reviewed:
<ol>
<li>Panasonic Lumix TS4 12.1 TOUGH Waterproof Digital Camera with 4.6x Optical Zoom
<li>Nikon COOLPIX AW100 16 MP CMOS Waterproof Digital Camera with GPS and Full HD 1080p Video
<li>Canon PowerShot D20 12.1 MP CMOS Waterproof Digital Camera with 5x Image Stabilized Zoom 28mm Wide-Angle Lens a 3.0-Inch LCD and GPS Tracking
<li>Fujifilm XP170 Compact Digital Camera with 5xOptical Zoom Lens
<li>Olympus Stylus TG-830 iHS Digital Camera with 5x Optical Zoom and 3-Inch LCD
<li>Pentax Optio WG-1 Adventure Series 14 MP Waterproof Digital Camera with 5x Wide-Angle Optical Zoom
<li>Olympus TG-1iHS 12 MP Waterproof Digital Camera with 4x Optical Zoom
</li>
</ol>

In case you are prepared to pay out approximately $1,000 to get the [http://www.squidoo.com/best-waterproof-point-and-shoot-camera top underwater camera] setup then one of the finest underwater cameras in the extreme camera market is absolutely the Olympus TG-1 iHS. This digital camera when purchased along with the optional Olympus underwater case and strobe enables the diver to take photographs in over 130 feet of water and in addition makes a very decent beginning level underwater camera for both the advanced and recreational diver. TotalThe e expenditure includes the camera, a rugged housing that permits the diver to take the camera to a depth of 135 feet and an independent strobe that provides the capability to photograph in a varity of diverse situations.

Wreck diving Grand Cayman - USS Kittiwak

Tights01vito — Mon, 11 Mar 2013 09:09:54 GMT

Tights01vito:

This is a great wreck dive in grand cayman and one of the best in the caribbean The USS Kittiwake which was sunk a little over one year and the shipwreck site is aging very well. The ship has five decks, is 251.6 ft (76.7 m) in length, 42ft (12.8 m) in beam and around 50 feet high. The ship was designated specifically for performing submarine rescues and was launched on July 10, 1945 and which was sunk in Grand Cayman in January 2011.

This article provides a description of the dive, some history and information about the vessel and an overview of what you will find on the wreck. Review the complete [http://stevenwsmeltzer.com/gallery/Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/ photo gallery] on the website and/or see the internet blogsite article for the [http://blog.stevenwsmeltzer.com/dive-site-reviews-and-listings/dive-sites/scuba-diving-grand-cayman-uss-kittiwake-shipwreck/ USS Kittiwake] for additional data on the shipwreck and a history of the ship.

The Dive:

The ship was reefed In january 2011 off the north end of Seven Mile Beach in Grand Cayman.

There are five decks on the [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Wcb0w0RopvI USS Kittiwake]. A portion of the upper part of the ship was removed to meet cayman requirements The are two bridges on the upper decks along with the navigation and radio rooms. The sonar was also removed from the ship. The Captain and executive officer's quarters are also on the upper decks.

On the main deck, from bow to stern, internally you will find the mess hall, toolshop, recompression chambers and rec room. You will also see a large [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000nrOSPnFJRtU a-frame structure] on the stern that rescue divers, along with the diving bell that was used to bring back divers to the ship and to then move to the recompression chambers

Below the main deck, 2 decks exist that include the crews quarter, medic/hospital station, engine and propulsion rooms,[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000QmV9jUuDJyQ air bank storage] and compressors, as well as ammunition lockers, cold storage, barber shop and other areas. While the USS Kittiwake has been opened up with large[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000evHtkg3GaYQ access holes] in the sides of the ship, all of the space on the ship was used when she was in service.

Make sure to lay out your dive adequately. I would recommend heading to the stern before entering into the vessel to take photographs near the[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000MlfKl.47lgI "USS Kittiwake" logo] on the stern and in addition get photographs by the propeller. For Scuba Divers that intend on penetrating the wreck, after you leave the stern make your way to the top of the ship and enter via the main funnel which is located on the Bridge Deck. Should you not intend on entering the shipwreck you can begin your investigation of the ship on the main deck just above the Screw..

The main [http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000ndu7PcxF.bM entry through the funnel can be a great location for underwater photography] and I would suggest taking the photo looking up from the bottom of the funnel to the top of the funnel. I would suggest silhouetting one of your dive buddies diving down into the wreck. You can exit into the ship on several of the decks including the first platform or in the cargo hold. Note the hold deck does not have any exterior exit points and is not recommended for divers that do not have an advanced certification and prior wreck experience. On the first platform you will be able to see the Engineering logo in the Motor Room section. This section can be accessed easily and can be the subject of a very interesting underwater photo close to the "[http://stevenwsmeltzer.com/gallery-image/USS-Kittiwake-Grand-Cayman/G0000JtpXOPWAQac/I0000Y0UeUwX5JJc Engineering Mural]". The sediment can be substantial here so you need to move slowly to prevent stirring up the sediment. For experienced divers you can also look at shaft alley and the front hold sections of the ship. For others you may check out the various areas on the first platform and then begin going up deck by deck until finally arriving at the Bridge (Pilot House) where you can do you safety stop as it is at about 5 to 6 meters or 15 to 18 feet.

Look at photographs of other [http://stevenwsmeltzer.com/gallery/Shipwrecks/G0000OtMyTETA74I/ shipwrecks] on http://www.stevenwsmeltzer.com or visit his [http://blog.stevenwsmeltzer.com/dive-site-reviews-and-listings/dive-sites/scuba-diving-grand-cayman-uss-kittiwake-shipwreck/ blog] for critiques of specific shipwrecks.