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1. Environmental factors that affect the intertidal zone

a. Activity Cycle and Inter-specific Competition

Intertidal activities are carried out in great proportions during high tide (J.R. Lewis, 1964).

Organism in the intertidal zones that are submerged in water, are surrounded by particulate foodmaterial such as plankton's, and detritus (non-living organic material dissolved in water.),

dissolved oxygen, carbon dioxide and nutrient chemical substances are plentiful and movement

ad locomotion is much easier. There is a definite relationship between high water periods and

vital life activities such as locating and capturing food, digestion and waste elimination, gas

exchange, finding a

mate and reproduction.

 b. Dessication

The effects of low-tide, during a hot afternoon causes organism exposed to the air, the sun andthe wind (note: in high tide the organism are bathe in water which in turn protects them from the

said elements.) causing moisture loss, however such organism like the bivalve for example have

adapted to such challenging conditions.

c. Temperature

Water having a High heat capacity, which is greatly and in some way affect all life. Variation of 

temperature imposed in the intertidal zone creates a tolerance level among all organism, as a

result all intertidal life contend is such struggle.

d. Terrestrial and atmospheric forces (Salinity, freshwater, climate and weather elements)

By definition the Intertidal Zone lies at the intersection of three distinct environments:

atmosphere, ocean and land. The terrestrial and atmospheric forces with which intertidal marine

organisms must contend are especially effective during low tide periods. Direct solar radiation,

as opposed to light filtered and refracted by a layer of water, may "burn" organisms. Inundation

 by fresh water in the form or rain may pose salinity related problems. The harsh effects of wind

and snow, which are obviously not found underwater, can destroy tissues mechanically. Finally,

 predation

 by terrestrial and atmospheric organisms such as birds, raccoons, coyotes,insects, and humans

with buckets in the tidepools, may take place at low tide. These factors will determine the

composition and extent of vertical

zones. As each successively seaward zone is covered for a longer total period of time, the effects

of these terrestrial forces are severe in the upper intertidal and lesspronounced in the low

intertidal. Indeed, there is a gradation of such effects which, whether considered together or 

separately, could serve to induce a zonation pattern within the intertidal as a secondary factor 

associated to tides.

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2. Adaptation in the intertidal zones.

a. Water loss

I. (Animals) Some organism evolve, by having adhesive glands, these glands secret a "sticky"substance that allow the organism to glue pieces of shell debris, this will help in reduction of 

moisture loss by which organism use the glued debris as a shield to protect them for direct

sunlight. Gastropods with a operculum or can seal much water within their chambers to keep in

moisture. Free-swimming organism such as crabs and fishes would actively seek shelter under 

rocks or wet tide pools, Still other species build tubes, burrow under rocks, or remain in the

damp sand or mud.

II. (Plants) Guard cells in plants helps regulate water, excessive temperatures cause the guard

cells to close the stomates while light, plentiful water, and favorable temperatures cause them to

open the stomates. Some stomates must be open even in unfavorable conditions so that the plantcan take in carbon dioxide.(of course according to Mrs. Isulat, Plants differ by location, some are

called Drought plants for a reason e.g. cactus which are CAM plants)

 b. Maintenance of heat balance

I. (Animals) Some would reduce heat by locating small pool's of water or by borrowing through

mud, in bivalves the sculpture or ridges in the shells serves as radiators. Some coloration reflect

light by selective wavelengths and others (mentioned in water loss I) have an extra water supply

which can be used in evaporating cooling

II. (Plants) By understanding, on what was written on water loss II, plants reduce photosynthetic

activity and respiration by closing the channels of light and carbon dioxide, allowing reduce

water loss, this in some respect allow plants to regulate heat because of the stored water.

c. Mechanical Stress

I. (Animals) Gastropods and Amphineurans clamp tightly in hard substratum to gain Anchorage

from the harsh tides, some organism have hydrodynamic shapes (e.g. Chitons, limpets, and

 barnacles) which can deflect the destructive forces of waves, not to forget some aquatic organism

evolve into a much elastic body.

II. (Plants) Plants having roots that borrow deep into the soil creates a tough anchorage. Algae on

the other hand are large and flexible, hence they bend as the wave simply pass over.

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d. Predation

I. (Animals) many of the intertidal inhabitants may be confined to a particular intertidal zone by

their predators. For example, fast moving predatory species may feed high up in the intertidal

and retreat before the tide runs out. Accordingly, the distribution of certain sessile invertebrates

such as barnacles, sponges, and even mussels may be explained more on the basis of predationversus movement, rather than strictly as an adaptation to submergence and emergence.

II. (Plants) Plants Spore more often (they reproduce more) when face predation

e. Osmotic balance/Salinity stress

(Animals) organisms would burrow deep where salinity is much lesser, Osmoregulators tightly

regulate their body osmolarity, which always stays constant, and are more common in the animal

kingdom. Osmoregulators actively control salt concentrations despite the salt concentrations in

the environment.

(Plants) Whilst there are no specific osmoregulatory organs in higher plants the stomata are

important in regulating water loss through evapotranspir ation and on the cellular level the

vacuole is crucial in regulating the concentration of solutes in the cytoplasm. Strong winds, low

humidity and high temperatures all increase evapotranspiration from leaves.

f. Respiration

Animals: In most fish respiration takes place through gills. Lungfish, however, possess one or 

two lungs. The labyrinth fish have developed a special organ that allows them to tak e advantageof the oxygen of the air, but is not a true lung. ]

Plant: They respire during the process of photosynthesis, because they need to oxide for 

enzymatic processes

g. Reproduction

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h. Anoxic Conditions

Animals: Animals can’t live without oxygen, the would probably have to dive deep where

oxygen maybe present, however unicellular organisms like some bacteria be mostly likely to

survive considering some are anaerobic.

Plants: Plant that live in anoxic environment, may have to use some of their adaptive feature,

some plant have adventitious roots, which can crawl above soil and seek oxygen, plants like the

 black mangrove, have pneumatophore or air roots. plant whose roots are above have specialized

structure called aerenchyma, roots that simply diffuse air form the aerial portion.

3. Zonation in intertidal habitats

Slope of the beach: There is some evidence that the settlement and attachment of certain larval

stages and spores is controlled by the slope of the beach. Some organisms feed, reproduce,

withstand environmental pressure, and thus survive betteron a vertical surface. Through naturalselection the larvae of these organisms can detect a particular inclination of the substrate. Some

larvae can delay their own metamorphosis and settlement for short periods until proper settling

grounds are recognized. Other species obviously do the same for horizontal environments.

Substrate type: Different types of substrates support distinct populations and communities. We

do not expect to observe mussels and barnacles attached to sand any more than we expect clams

and sand crabs on rocks. The nature of the substrate plays an important role in determining the

abundance and diversity of life within the intertidal. The effects of substrate on vertical zonation

can be considered along the following three lines: a. Attachment of larvae, b. Success of larvae

and juvenile stages based on porosity of the substrate, and c. Success based on movement of thesubstrate.

4. Importance of study

Scientists are interested in studying the rocky intertidal zone, because it is a highly structured

 biodiverse region. In the past, research was limited to small sample areas. Scientists would study

either physical factors or biological factors. This information was valuable, but it didn’t help

scientists understand the overall picture. They wanted to learn more about what was happening in

these areas and how this affected surrounding environments.

5. Organisms found in the intertidal zone

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a. Plants

 Nail brush seaweed (Endocladia muricata)

Black pine (Neorhodemela larix)

Turkish washcloth seaweed (Chondracanthus exasperatus)Sea lettuce( Ulva Lactula)

Rock weed (fucus Vesiculosus)

 b. Epifaunal invert

Rock louse (Ligia Occidentalis)

Periwinkle (Littorina Planaxis)

Marble Crab (Pachygrapsus Marmoratus)

Upper barnacle (Chthmalus fissus)

True limpet (Lottia digitalis)

c. Infaunal

d. Vertebrates

Harbor seal (Phoca vitulina)

Black oystercatcher (Haematopus bachmani)

Monkeyface eel/prickleback (Cebidichthyes violaceus)

 Northern clingfish (Gobiesox maeandricus)

Ruddy turnstone (Arenaria interpres)