Seagrass Systems

Sea-grass systems are marine phenomena, and the beds are bioengineers that stabilise the sediment and change the chemical composition to suit them. The grasses are very well adapted to their niche, since there is often less biological, physical and chemical stimulation to change. Sea grasses are actually angiosperms that flower, much like terrestrial grasses, and indeed they are organisms that have returned to the marine environment from a terrestrial ancestor.

Biomass and productivity vary latitudinally, being greatest in tropical waters. The Mediterranean basin used to be hypersaline, so it seems only natural the sea-grasses should have inherited it. The major polyhaline species can handle a wide range of salinities, but only the Halophila spp., are truly marine.

Sea-grass meadows as a food source

Few animals appear to directly rely upon sea-grass production as a food source, although some fish, turtles, sirenians and sea-urchins with ruminant-like cultures of cellulose-splitting bacteria in their guts are noticable exceptions. Most consumers however are dependent upon the decomposing grasses, and bacteria and fungi are critical in rendering plant material digestible. Aged sea-grass is assimilated much more than artificial detritus.

Sea-grass detritus is rich in micro-organisms, and one gram supports on average 10^9 bacteria, 5 x 10^7 heterotrophic flagellates and 10^5 ciliates. Living sea-grasses also provide an attachment site for epiphytic algae both macroscopic and unicellular,a nd other algae occur between the shoots and in surface sediment layers. The benthic algae may actually account for 70% of the total primary production recorded, but thick carpets of leaves reduce the light intensity reaching the benthic flora.

Species 

Zostera marina: These have a rhizome root system and reproduce vegetatively, growing from the dead, older shoots. 

Halodue beaudettei: This shoal grass is found in deeper waters, and creates a boundary layer effect. It has a broader surface area to absorb more light and resist against strong currents. 

Halophila decipiens: Paddle grass.

Syringodium filiforme: Manatee grass.

Posidonia oceanica: Characteristic of the Mediterranean; P. australis is only found in Australia. 

Thalassia testudinium: Turtle grass. 

Biology

They have strap-like, flattened leaves, with blades, an extensive root and rhizome system. They have no stomata, being underwater, so do not worry about water loss; for the same reason they also have thin cuticles. Sea-grasses also have large, thin-walled Aerenchyma tissue, which is used for gas exchange and buoyancy. Lacunae are continuous channels used for gas transport to the roots, and the roots themselves have hairs to increase surface area. They are halophytic (salt-tolerant), and can obtain nutrients from the sediment and water column through roots and leaves.

Associated fauna:

Sea-grass is extremely important for conservation purposes, being the key food source for sea turtles, parrot fish, surgeonfish, sea urchins, the queen conch, manatees and dugongs. Sea-grass ecosystems are usually surrounded by nutrient-poor waters to concentrate this effect, and over-fishing of the Queen Conch (Strombus gigas), which are epiphyte grazers, threatens the balance of the whole system.

The Sirenia order include the Trichechus manatus and Dugong dugon, and these sea cows rip out the root system of the sea grass they graze, causing pernament damage and placing pressure on the sea-grass bed. Sea-grass is also vulnerable to storm damage on top of excessive grazing, alongside dredging, boat damage, pollution and wasting disease. 

Mangal Communities

Mangal communities are specialist habitats, yet have a biodiversity lower than might be expected. They are intertidal, low-energy, heterogenous environments that allow the build-up of sediment and are typically tropical, with fast-growing species dominating.for instance, Mangroves. They are coastal communities, the tropical equivalents of temperate salt marshes, and are found on 75% of tropical coastlines. Mangroves may only grow where the water is shallow enough; sediment deposition occurs; light is adequate and water temperature is above 50C.

Mangroves facilitate sedimentation by reducing water velocity and retaining deposited particles; vegetation succession establishes itself over time, and the physiography of the system is dominated by creek networks, and provide the routes through which water floods and ebbs. The aerial shoots and branches of mangroves are essentially terrestrial habitats.

Succession: The orderly process of change over time in a community, which cause changes in the physical environment and allow another community to be established. The gradual improvement of an environment's hospitability. 

Zonation: The arrangement or patterning of plant communities or ecosystems into parallel or subparallel bands in response to change in some environmental factor. An area with a dominant climax community.

Mangrove Species

All Mangrove species are capable of inhabiting the intertidal zone, but some are better adapted to the more interchangable conditions. White mangrove (Laguncularia racemose) and Buttonwood (Conocarpus erectus) are both terrestrial species, housing birds, bats and other mammals. E.g. the long-tongued nectar bat, a key pollinator for the mangal community. The marine-adapted species are the Red mangrove (Rhizophora mangle) and Black mangrove (Avicennia germinans). 

Mangroves are fast-growing, which means the are has lots of particulate organic matter (POM) - this infers a high bacteria rate. No benthic algae can grow as the mangrove roots block the light. Anoxic sediment thereby develops, containing sulphide, and most anoxic sediments are found in the seaward zone where the Red mangroves grow. Mangroves exhibit discreet species settlement and won't outcompete and replace each other over time - hence it is thought mangroves align through zonation, not succession.

Tidal regime

As landward areas dry out, high salinity and desiccation occurs; salt crystals can form with evaporation on the mangrove leaves; rain and tide are required to wash it away before it damages the plants by impacting their osmotic movements. This process is called tidal flushing, and it is also useful for removing the sulphide that builds up in anoxic sediments. Tidal immersion hydrates and provides nutrients too. Early studies indicated 50% of net plant production of these areas was exported by tidal flushing - these systems can therefore be considered significant carbon supplies to the continental shelf. 

Adaptations to anoxic sediments

Colonisation by plants stabilises the sediment, but tidal immersion limits oxygen exchange; high detrital input from plants leads to high bacterial mineralisation rates, leading to anoxic sediment. For this reason, Mangroves have pneumatophores, negatively geostrophic roots up to 3m in length - these aerial roots allow the direct gas exchange of oxygen in to the roots.

Lenticels are pores in the roots which allow gas exchange but not water and solutes, enabling oxygen to be transported through channels in the aerenchyma tissues, keeping out salts. they are found n pneumatophores and prop roots. 

                               

Avicennia spp., takes in salts through the plant roots, which it transports to the leaves through the plant sap. The sap concentrates the salt at 3-4 SU, and secretes it out through salt glands and the leaves. The root membranes are semi-permeable, so exclude most salt ions to limit uptake. 

Non-salt secretors such as Rhizophora and Bruguiera spp., are extremely tolerant of salt storage through ultra-filtration, which is a high-energy process but very successful. The system is complex but radial filtration occurs in the roots, where an ion pumps in the xylem and salt is stored in ion-saturated filter cells that are sealed off with a suberin coating. These cells are lost when the leaves shed and are pushed back down the plant by growth.

Mangrove Reproduction

Mangroves have viviparous seeds that germinate on the parent plant: vivipary describes germination within the parent, and this occurs within the Rhizophora spp., and Bruguiera spp. The embryo grows out through the seed coat, giving it a head start for growth. When the seed falls from the plant it immediately begins to compete with its parents, so the head-start is incredibly important. Cryptovivary occurs within the Avicennia spp., where the growth does occur but is not visible to an outside observer. The embryo here only grows out through the seed coat and not the fruit wall before it splits open. 

If the seed drops during high tide, it will be taken with the currents and deposited elsewhere, where competition is likely to be lower, but the environment may be less suitable. If the seed is dropped during low tide, the habitat is guaranteed to be suitable, but competition will be higher. 

Mangal Community Fauna

There are several key indicator species within mangal communities. For instance, the Mangrove oyster (Saccostrea cucullata), snails such as Cerithidea obtuse, and barnacles such as Littoraria  carnifera. Decapods including the Fiddler Crab (Uca chlorophthalamus) are also present. Chelicerates include spiders, mites and horseshoe crabs, creatures that evolved 4 million years ago unchanged. Fish present include the teleosts such as Mullet spp., (Mucilidae) and the cardinal fish - juveniles in mangroves that breed on corals. The giant mudskipper is also a key organism (Periopthalamodon schlosseri), alongside the Archerfish (Toxotes jaculatrix), which spouts water out at invertebrates to knock them off their branches. Mammals and birds include the long-tongued nectar bat, Golden Plover, Little Egret and Striated heron. One mangrove gastropod, the Cerithidea decollata, migrates vertically throughout the day, as it forages on the mud surface during low tide before retreating back on to the trees well before the incoming high tide. Their irregular behaviours and migration patterns however mean their actions cannot be explained by internal clocks, and direct cues seem to be based off of local conditions, rather than a universal genetic tendancy. 

Human uses for Mangrove species

The Rhizophora mangle is used for timber, paper pulp, cattle fodder, tobacco substitute, wine, fishing line and medicinal purposes. They grow up to 30m tall, and may be easily cultivated. The Avicennia germinans are not useful for timber, but are a soap substitute, and the bark may be used in  tanning, and its flowers are important for the local honey industry.  

Sources: My own lecture notes. 

Vertical migrations of the mangrove snail Cerithidea decollata (L.) (Potamididae) through a synodic month Marco Vannini a,*, Cecilia Coffa b , Elisabetta Lori c , Sara Fratini a. 2008. Estuarine, Coastal and Shelf Science. 

Estuarine Systems

Estuarine systems are transitional between open marine and fully freshwater environments, semi-enclosed water bodies with a free connection to the open sea. The variability of their physical, chemical and biological properties has profound effects upon the nature of the estuarine biota.
In these systems, phytoplankton growth is limited due to the high sediment suspension, which blocks or absorbs light; biofilms composed of diatoms and sugar polymers bind the sediment, and this is an excellent food source. Whilst an estuary is a heterogenous system, it is a stressful habitat that limits biodiversity they do support micro-environments however, with their own salinities and nutrient loads.

Types of estuary

1. Coastal plain estuaries ; formed at the tail-end of the Ice Age with rising seawater level. They are the commonest type of estuary, such as Chesapeake Bay. 
2. Bar-built estuaries; these are semi-enclosed lagoonal, shallow estuaries principally in low-lying regions where shingle or sand bars partially isolates river water from the sea e.g. Dutch Waddenzee.
3. Tectonic estuaries; the sea has invaded the land by tectonic processes resulting from land subsidence, particularly along fault lines e.g. San Francisco Bay. 
4. Fjords; drowned glacial valleys whose estuaries are deep and narrow with a submerged sill, restricted water circulation at lower levels, and are prominent in Norway, Chile and Columbia.

The Salt Wedge

The shape, width and length of the estuary determines how well-mixed the system is: geology determines geomorphology determines ecology. The salt wedge profile is indicated by isohalines, which are distorted due to boundary layer effects, and a reflected wave from an incoming tide (a standing wave) aids in the mixing of fresh and saline water. 

In the highly stratified estuary, sea water invades the river bed, with the less dense fresh water flowing over the top; frictional forces at the interface cause entrainment of some sea water upwards in to the freshwater layer, meaning there is a continual slow upstream flow within the salt wedge. A halocline exists between the two masses as mizing is marked discontinuous. Superimposed on such mixing circulation patters is is the Coriolis effect, which deflects water to one side of the estuary. 

Water mixing

Energy inputs in to the system control water mixing - wind (turbulence); heating & cooling (stratification & turnover); tide (flood speed) and gravitational circulation (salinity gradient). The Reynolds ratio number divides the power to mix by the power available: RR > 0.8 is a stratified system, if RR < 0.08 it is fully mixed.

Sedimentation

Fine particulate material flocculates when it encounters salt water, and larger flocculates sink to form a liquid mud on the surface of the submerged mud-flats. In vigorous vertical mixing some particles will be resuspended, deflocculate and repeat the process. Sediments may be derived from the freshwater, some are carried in by tidal flow. Sedimentation is largely related to seasonal fresh water input, storms and floods. Sediment sources may be autochthonous (originate from within the estuary) or allochthonous (imported in to the estuary from other sources). 

Muddy cohesive clays, mixed and sandy sediments are all found; clay is composed of lamellae plates which are all negatively charged, meaning they cannot combine. The addition of water, with positive hydrogen iions, binds to the particles as the Van der Waals forces attract. Interstitial water with positive ions from the water column and biological polymers reduce the clay repulsion and improve cohesion.

    

Estuary productivity

50% of productivity is benthic, so the estuarine environment is based on bottom-up control - nutrients are often a severe limiting factor. Phosphorous binds well with iron compounds in fresh water, but less well in saline water; it is released by diffusion in to the water column. Nitrogen is usually used up before it reaches an estuary and is generally limiting, its availability controlled by bacterial mineralisation. Muddy sediments are unsuitable for macroalgae attachment, although saline-tolerent species such as Enteromorpha spp., or Ulva spp., are seasonally abundant. 

Adaptations

Microcycling describes the behaviour of diatoms according to light variations; when light intensity is too bright, the diatoms bury down in tot he sediment, but dig upwards when there is a defecit - this migration is not understood. They are grazed directly by Hydrobia snails and shrimp.

Osmoconformer species regulate neither cell volume nor ionic composition - they are tolerant to a large variation of ionic concentration in their body fluids. Internal ospmotic pressure changes depend on the extreme osmotic potential, and body tissues must be tolerant e.g. Nereis diversicolour. They are much more restricted in habitat range.

Most marine species exhibit varying degrees of osmoregulation. Some organisms even alter the concentration of disslved free amino acids in response to changes in external salinity. They maintain a constant osmotic potential irrespective of the external changes, but this does have metabolic costs - they are able to colonise a wider range of habitats however e.g. Upogebia spp. - mud shrimp.

Food web 

Estuaries are rich in detrital feeds, which may be deposit and suspension feeders - two means of feeding not mutually exclusive. Susepension feeders are rarer because such delicate filters may become easily clogged - despite this, there are several locally abundant, commercially exploited species such as Crassostrea virginica. Detritus feeders ensure continual bioturbation.

Rocky Shore Ecosystems

A rocky shore is usually a high-energy shoreline (compared to areas of coastal accretion), with high erosive forces stemming from waves, wind and tide.The shore is the transition between marine and terrestrial environments, and creates a habitat wherein neither fully marine nor terrestrial organisms can flourish; emersion and dessication is stressful to marine organisms, while immersion is stressful to terrestrial creatures. The transitional gradient seen between the two dissimilar environments creates an intertidal zone with notable zones, although the effects of wave splash and spray extend beyond High Spring Tide Level, meaning the gradient between marine and terrestrial is not entirely embraced. In British shores, sheltered shores are often dominated by fucoids, macroalgae, whilst exposed shores are dominated by barnacles and mussels.

 Fetch describes the distance of open water across which the predominant wind blows; this builds up energy in the form of waves, and the energy determines whether a sandy or rocky shore develops. 

In polar regions, crevices and hollows are formed in the rock by ice scrapes and are the only areas in which organisms can survive, unless they migrate to the sublittoral zone. Deep freezing and summer thaw both create harsh environments. In tropical regions, higher light intensities, temperatures and dessication at low tide are incredibly hostile towards macroscopic algae; it is below the Mean Low Tide Level biodiversity climbs.

Zonation

Competition for resources and the environmental conditions are the two factors responsible for zonation; it is a manifestation of resource-partitioning among potentially competing species,a nd linear zones reflect the linear nature fo the environmental gradient. For sessile, sedentary organisms, several physical factors determine the extent of suitable microclimes;

• The slope of the shore determines the amount of suitable rock surface
• Tidal amplitude will affect wetting and submergence
• Greater wave action will push the zonal boundaries further upshore
• Shore aspect will affect the amount of drying out at low tide, and shaded slopes will remain damp for longer than sunny slopes. 

Macroalgae

Higher competition is experienced here, and macroalgae such as Liminaria digitata are found growing from a holdfast; a stipe developes and branches out in to fronds, which are composed of the lamina, thallus and blade. They are adapted to minimise water loss with a mucilaginous coating and channelled thallus. All macroalgae must be submerged to photosynthesise efficiently, and some species have bladders for buoyancy. They grow through meristematic cell division at the algal apex, and reproduction uses haploid gametophytes, which produce gametes that combine to form a diploid zygote. This grows in to a diploid organism. Meiosis in the sporophyte leads to the production of the haploid spores that may be flagellate, and grow in to gametophytes. Macroalgae may also be monoecious (self-fertilising), although are generally dioecious, releasing sperm/spores at high tide. Macroalgae reproductive cycles are connected to a temperature threshold and have lunar cycles!

Zonation at Bembridge rocky shore, Isle of Wight (http://www.medinavalleycentre.org.uk/resource/bembridge-marine-life/).

Animals

Consumers include the porifera (sponges), anthozoa (soft corals), annelids (worms) and pycnogonida (ticks and mites), bryozoa (colonialists), crustacea, mollusca and echinodermata (starfish). Increasing mobility on a rocky shore would reduce the effects of physical environmental stress on zonation, which may be influenced more by the distribution of protective microhabitats or food supply. 

Molluscs: These include the gastropods; topshells, limpets and winkles. Trochidae (topshells) such as Monodonta spp. or Gibbula spp., exhibit a tooth and have mother-of-pearl inners. Patellidae such as Patella spp., and Andsates pellucida are blue-rayed limpets. Littorinidae are primarily Littorina littorea and Melaraphe neritoides, and are shelled organisms, soft-bodied with a muscular foot. 

The operculum is a piece of shell that seals the arpeture when the organism retreats inside, to prevent water loss and protect from predators. A larger shell surface area with ridges minimises heat loss and increases the enzyme tolerance to fluctuating temperatures. The camoflage and position on the sea shore decreases the chance of predation. Most molluscs are dioecious, and the larvae are planktonic, named veliger larvae. 

Crustacea: This includes the cirripedia; barnacles such as Cthalamus montagui and Semibalanus balenoides, and the decapoda such as Cancer pagarus. Cyprids of both settle on suitable substrate throughout the intertidal zone down to the sublittoral zone. Semibalanus balenoides cyprids can cement down their antennules in 20 minutes. However, they are incredibly intolerant to dessication, and have a calcareous plate system to improve resistance, and close over the aperture during emersion. They are well adapted to temperature variation, with enzymes capable of tolerating high temperatures. Cement glands facilitate fastenings to the rocky substratum, where they feed on plankton and detritus. They also have huge penises that fall off after sex. 

Indicator Species

Pelvetia cannaliculata is found in the Mean High Tide Level and is characterised by its surface mucilage, channelled fronds, and enzymes/pigments resistant to high temperature. 

Fucus spiralis is found in the eulittoral zone, with a higher tolerance to dessication, but a slower growth rate. It is easily out-competed by Fucus vesiculosis and Fucus serratus. 

Littorina saxatilis is a large-ridged top-shell, well-adapted to low temperatures, with an operculum and thick shell, and they are found in rocky crags. 

Fucus versiculosis is found in the upper eulittoral zone and is tolerant to heat shock, but not as well as Pelvetia cannaliculata. It is further out-competed by Fucus serratus. 

Chondrus crispus is found in the low intertidal zone as a dominant competitively superior species.

Space on the substratum is an essential resource for sedentary organisms, and may be provided by the rock surface or biological surfaces (secondary space); it is non-renewable since once occupied, no more space is forthcoming. Food resources by contrast are renewable, so is not so fixed in extent, imposing a limit to the number of sessile individuals able to occupy a zone. Therefore, space is the most essential resource and can quickly become both a physical and biological limitation; for instance, reduced area for attachment, deformed growth, undercutting or smothering, alongside reduced light accessibility, algal films reducing growth and reduced reproductive output.  

Human exploitation 

Intertidal plants and animals are harvested commercially; consider the Concolepas concholepas fishery in central Chile. They farm a carnivorous gastropod whose diet consists of mussels and barnacles, and grows to a size large enough for human consumption. Where C. concholepas was fenced off from farmers and allowed to function normally in the community structure, the previously mussel-dominated rocky shore became cleared to allow colonisation of barnacles and macroalgae. Mussel domination in Chile is the result of human exploitation; both fishermen and C. concholepas are keystone species controlling the community of these rocky shores. 

                              

In New South Wales, shore fishes are caught using intertidal ascidians, crabs and gastropods for bait; following this decimation it has been concluded that sanctuaries excluding people from the shore may significantly improve adjacent fisheries and preserve breeding populations of the exploited invertebrates. 

Renewal of secondary space and of non-hierarchal competition 

Physical and biological disturbances are incredibly important for maintaining species diversity; sedentary organisms form linear, competitive hierarchies, and space is a non-renewable, limiting resource. Undisturbed, such a system would eventually lead to monopoly.

Fucus serratus grows prolifically on sheltered shores, supporting epifaunal communities with a high biodiversity, controlled by the summer growth of the plant, which replenishes the substratuma vailable by up to 75% every year. 

Patch dynamics 

A rocky shore often exhibits 'patchiness' within zones. It is nested in the population distribution on a scale of kilometres, and different biological/physical factors will operate on the different spacial scales. The patch mosaics within zones reflect varying forms of space occupation by intertidal organisms, and as patches become bigger, colonisation from immigration between patches will likely occur. 

Photosynthesis

So exam season has rolled around, a particular time of the year that brings out all of the allergies, chiefly those towards increased post it note break outs, library dust and the excessive consumption of digestive biscuits. As such, I'm going to start compressing everything Marine Geography in to a series of blog posts, chiefly to make it more digestible for myself. Anyone reading, feel free to enjoy.

Photosynthesis

Primary production supports all food webs, controls the atmosphere, and has produced a series of marine ecosystems cumulatively worth $400 billion - therefore, photosynthesis is a major control over socio-economics. Photosynthesis is the coupling of the conversion of light energy to chemical energy and inorganic carbon to organic carbon. Simple, dissolved organic compounds may be converted in to more complex substances via photo-assimilation. 

Rates of primary production are greatest in the coral reefs due to the endosymbiotic relationship between animal and algae - the reefs themselves actually grow in oligotrophic waters. Seagrass beds also have a strong production rate, aided by epiphyte macroalgae that grows on the shoots. The Antarctic Ocean has very strong vertical mixing, causing a nutrient upwelling that significantly boosts productivity. 

Light of 400-700nm wavelength powers the essential first stage of photosynthesis, and is absorbed by photosythetic pigments such as chlorophyll a - this substance exhibits peak absorption of light wavelengths of 670 - 695nm. This photosynthetic fixation generates the organic compounds of the sea, and the gross production will be broken down by the respiratory metabolism of the photosynthetic organism, incorporated in to its tissues and fluids, or constitute growth.

Light-dependant reaction: 

As solar energy hits a chloroplast, the electrons become excited, and will exit the chloroplast in to the membrane. There they will be taken up by the electron transport chain, and participate in a series of redox (reduction oxidation) reactions, producing energy. The final acceptor for the electron transport chain (ETC) is an NADP molecule, which then becomes reduced, usable for the light-independent reaction. Water is required in this process, and undergoes hydrolysis; the H+ is utilised by the chloroplast, the oxygen molecules are by-products. 

Light-independent reaction (Calvin Cycle):

This involves constant regeneration, and is activated by RUBSICO (ribulose biphosphate carboxylase/oxygenase), an enzyme that may be bound with carbon or oxygen: for this reason a competitive state exists between the oxygen and carbon dioxide connection. However, with 45x less oxygen in the ocean than in air, the carboxylase function dominates, which is much more efficient. The five ribulose biphosphate carbon molecules are therefore synthesised with two carbon molecules to produce phosphoglycerate. ATP molecules donate one phosphate molecule each to the PG in order to form two biphosphoglycerate chains. Reduced NADP then donates H+ in order to reduce the substance and produce glyceraldehyde-3-phosphate. This is then broken down in to organic compounds, glucose and partly regenerated for continuous use in the cycle. 

Limiting Factors

Light

Longer wavelengths preferentially excite the photosystem: it is absorbed exponentially with distance in the water column, and much of the solar radiation is in the infrared section of the spectrum, absorbed in the first 2m of a water body. The photocompensation depth describes the point at which there is no net photosynthesis - respiration balances it out. Above this depth, phytoplankton may grow and multiply; belo they must subsist on accumulated reserves from inactive resting bodies, or starve. In high intensity light, an overflow of photo-oxidation and the destructive impact of UV radiation accounts for a decline in photosynthesis. On the water surface, excess light may result in photoinhibition, whereas at depth, light intensity will be a limiting factor.

Turbulence

The compensation depth is a balance point in the metabolic physiology of a phytoplanktonic cell.Wind-induced turbulence may extend to depths of 200m, while the photic zone may be much more shallow. The critical depth describes (in terms of irradiance) the depth where light intensity is equal to the compensation light intensity.  Hence, if the depth to which mixing takes place is higher in the water column than the critical depth, then the average light intensity experienced by a photosynthetic organism will be less than the photocompensation depth. Mixing often extends below the critical depth during the winter in high latitudes, causing a negative production until mixing decreases as with the wind velocity, or light intensity increases with the spring/summer seasons. 

Nutrients 

If the mixing depth is less than the euphotic depth, then nutrients will be the limiting factor to photosynthesis. The primary macronutrients are nitrogen, phosphorous and potassium. Nitrogen is necessary for the formation of amino acids, cell division, and it is directly involved in photosynthesis. Phosphorous promotes early root formation and growth, increases water-use efficiency, and is involved in almost all metabolic processes. Potassium increases photosynthesis, and is essential to protein synthesis; it also activates enzymes, controls their reaction rates, and directs the carbohydrate metabolism. Nutrients are known to be depleted during warm-season thermoclines, and production decreases with it. When nutrients are enriched artificially, such as with effluent runoff in to a semi-enclosed bay, productivity is increased, sometimes to the point of eutrophication. 

Measurement

Traditional measurements of primary productivity and biomass often involve destructive sampling or are intrusive to the system. Recently, fluorescence measurements have been taken from chlorophyll a, in order to measure the light energy emitted from the light harvesting pigments. Productivity may also be measured by recording oxygen evolution with an electrode or Winkler titration; carbon -14 uptake may also be measured as a method of determining productivity. 

A word to while away the time

Race, race through the stormy night;

The crow arches its back

And sings –

The moon yawns at the quiet sight.

Two creatures they run,

Milky light upon hands warm

With heat the ocean brings –

Dance in the grass with great delight.

But where are you going, on this fine night? Does the grass curl or unfurl at your feet? Struggle on the through the scathing peat; in a warming world you must tread light.

The eyes of the children

They open wide to acknowledge

The heavy colours –

Did you see more then?

Breathe in sharp, breathe in deep;

The crow will not sing

Nor steal your gold –

But the tiger in the forest, will forever weep.

Have you seen the road, that which we dig? Do you know how to lead? Run, run, do not stop to breathe, for in the balmy night breaks the heave, the heave of the sickly oil rig.

Ask a question, ask three or four;

Challenge the script written in the stitches

Woven across too tight –

The material cannot take the strain any more.

The vasty ocean has so many corners, but too many hands to hold; eventually what thinks you, to an escape true? What. Be. May? Thinks. You. Do?

Communicate.

Can I?

Against the tide we have watched our fellow people reclaim the land of the past; a lady’s stomach swells with the population and fishermen cling to their masts as the tide turns. It is the time of itingaaro, the dawn twilight and the rooster calls out to wake up, wake up! Because the tide is turning. An unwelcome intruder and children shiver in case it murders the gentle innocent herder without shoes. Weathered feet born to walk the earth? Are they those that earn the right to be able to feel its soil? Take the culture, it can be replaced and when you are not looking we will build a wall, a wall made of earth to keep you out. And still the lady’s stomach swells; the tide is as full and taut as her skin, and it stretches to the horizon.

The clouds darken over the lagoon and the tide cuts through like dark glass, the axis of our lives, and it lacerates the land, flushes salt in to our cuts; the call is sharp, sharp as knives. The heat is on, and we walk in the thick of it, playing with the dials but our hats we don, a uniform response in case we fall in to the pit. Who are the defeated people? Not I, who writes but only watches; a walker without shoes, perhaps. Sand bags placed on a sandy beach will not stop the tide.

The white-walled economy washes over the island, the saltiest tide of all and a tie washes up on the shore. Sure.

The ocean doesn’t breathe.

And we scour the Earth.

Anti-food waste: The Real Junk Food Project

So around the corner from  the patch of space where I reside, a new cafe has opened up: a Pay As You Feel Real: Junk Food Project cafe, and I gotta say, if we all switched to a good binge on this kind of junk food, we would all be a lot better off.
The premise of the cafe is quite challenging, but essentially takes wonky fruit and vegetables supermarkets and the like would ordinarily bin, and use it to create super health meals. I know what you're thinking. Wonky vegetables? Disgusting. Curse those auxins and the lack of Abscisic acid. If my carrots aren't as straight as the posture of a Prince with a broomstick up his arse, I will have none of it.

Around one third of the food we produce globally is wasted for a variety of reasons, often needlessly. At the same time, around 795 million people don't have enough food to eat healthily. So these guys work on a grassroots level and intercept food wastage from local stores, food that is needlessly wasted. Like wonky cabbage. Wonky carrots however, awful.

Cathays, Cardiff.

Travelling to Albania: Step One

So, after giving my lovely companion a Lonely Planet Guide to Europe, but fairly restricted by crippling debt and the difficulty of maintaining $$ work in the final years of university, we have opted to travel to Albania! A quietly emerging country it seems to be, one of the Balkans, this place appears to be perfect for the more weathered traveller looking for a rugged, eu naturale vibe. Indeed, first glimpses have shown Albania to be a home to mountains, beautiful beaches along the Riviere, a wholly foreign composite of fauna and flora, and an intrinsically intriguing culture.
                             
This is not the first time I have planned and travelled independently, having previously wandered through Mozambique, Swaziland and both the northern/southern parts of India, and I have always kept a journal during my time there, but this time I've decided to start blogging my progress of planning this latest escapade. At the very least it will share my method of sewing together a plan for travelling that might help fine tune the hefty research of yourselves!

Now, we are thinking of going for two-four weeks tops (lovely friend having an adult-world job etc etc), which I've budget to be anywhere from £500-£1000, naturally increasing from one figure to the other with time extension.

I could rattle off flights etc etc., but really, the most important thing first is to clarify: what do you want to do?

For us?

A little bit of city, trekking, and finally beach. This is layout I've enjoyed before, because the trip is then more exploratory, and gradually winds down to a chill-out right at the end (BEACHBEACHBEACH, lassis on the beach).

This is where I get pretty split, because on the one hand the Islands of Tsamil, Borsh, Himara and Dhermi look to have fantastic beaches, right down in the south of the country. For us though, that would mean cutting out the Peaks of the Balkans, right in the north.

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So it turns out the Peaks of the Balkans are accessible, to a degree, in Korce,, 27 miles out from Berat! After a few hours of research I've devised a travel triangle from Tirana to Berat (3 hour bus), to Korce (27 miles minibus/2 day walk), Korce to Sarande (9 hour bus), Sarande to Gjirokaster (1 hour buss), Gjirokaster to Tirana (7 hours).


And this is step 1 of planning the journey done.

A Will To Change

We. Are a strong nation. We. Are a proud nation. We have our principles. And we do not back down. The conviction of the United Kingdom has inspired such pride in to my swelling chest throughout my lifetime, and what has particularly uplifted me on this jovial cloud of triumphant impression and glee is the forward thinking steps we are taking in the right direction.

Oh, I'm sorry. Turns out our navigator was holding the map upside down and a gorilla with a kidney infection urinated all over the bit that shows the (moral) compass. I mean, digging up the National Parks seems like a good idea...."frack off," am I right?  But at least we're on a soggy, smelly path (quite literally if you're one of the unfortunate flooded), which is of course, better than no path at all.

 I mean, some people are trying at least trying to get us on track to a sustainable lifestyle, and doing pretty damn well - or maybe my judgement is clouded, since next to the Conservative party a dog taking a dump on a daffodil to try and make it grow faster looks like a pioneer in Green policy.

What I find truly shameful, is that for all a happy stereotype's worth of us Britishy Britons slam America for being a devolved version of the United Kingdom (that pro-gun policy though, I mean, ease up on the testosterone or you'll end up overdue a castration after the testicles gargantuan themselves and overtake the brain), America's own Mark Jacobson has developed the most ingenious road map for the United States that has been thought capable of eliminating the U.S dependency on fossil fuels.

Who would have thought that making a pre-existing infrastructure 10x more efficient would be a faster, more beneficial and straight up valid way of straightening out the mess of global warming that's smeared its way across the planet like a fresh cow pat over a pair of Jimmy Choo's?

The feat is a leap in to the dark, and as has been the way with many a sensible scientist, he has met his fair share of rebuttals (but at least he's not been imprisoned, dishonoured, burned at the stake or clobbered to death by Newtonian apples - Newtonian apples of course, simply being all of the apples).

What the plan needs:
- 78, 000, 000 rooftop solar systems
- 49,000 commercial solar plants
- 156,000 offshore wind turbines

I really don't know why all new buildings in construction currently aren't forced to simply install solar panels all across them. Easy game. Easy energy. The artistic impression of architect Vincent Callebaut's idea for a sustainable Paris is stunning for instance. A positive mecca of green empowerment!
                    

Welch (2016) in the National Geographic rated Jacobson's plan as on par with other "ambitious endeavours" such as the nuclear bomb and military WWII arsenal. I mean. Perhaps not the most attractive comparisons to pull when trying to sell such a grandiose idea to a wavering, very American public, it can't be denied those other "ambitious endeavours" weren't successful. And it does seem quite unlikely all the implanted green technology would spontaneously, simultaneously combust as a measure of some sinister military feat - unless you're in a new-agey Stormbreaker novel.

The Cave of Crystals, Doorstep of Death, Maker of Malodours and Most Spectacularly Soggy of Spectacles

Caves. Are dank. Wet. Pitch black. Dangerous. Often times rather unpleasant. But they also house the most spectacular fauna and flora; beautiful formations grow within, and the heavy, hushed gravity of the systems are something well worth the visit. Indeed, there is no experience as refreshing as, after having been underground for eight hours, resurfacing out of a little, half-built hole in the ground and smelling the clean air, the fresh grass and often livestock, all senses feeling heightened after the cut off that is being within a cave (I've put in some pretty pictures to prove how marvellous caves are at further down).

The gifts humanity leave the Earth as we walk across it, poke our fingers in little holes or touch things we shouldn't, also often end up as dank, rather unpleasant growths. Rather akin to a verruca-infested kid bombing in to a swimming pool, shredding its warty skin all over the unassuming, dermatologically-content public.

And yet I am in the process of drawing up a research proposal to investigate and pinpoint the key bacterial human indicators present in the cave systems of South Wales, with the intention of them being potentially usable for an index of biological integrity in cave systems. This can hopefully be linked to future use in environmental impact assessment and cave management strategy.

There are specific micro-organisms to be looked out for over a four-month study period:
Staphylococcus aureus - skin micro flora present on/within human epidermal tissue.
Fecal coliform bacteria and E. Coli - present in the gut and feces of warm-blooded animals.
Alternaria and Cladosporium, strains of filamentous fungi, which commonly grow on cereals, simply owing to the fact that if any food debris is going to be dropped, it will likely be cereal bars hastily stuffed into overall pockets on a caving trip.

(If you have any comments/interest in this baby proposal, feedback would be gladly recieved)

Hopefully, in identifying the true extent of the impact of human breach into the cave systems, or the lack thereof, the management of the caves can be improved - or not. But at least another little insight in to the hidden ecosystems of the caves would be greater understood.

Just to demonstrate how truly incredible caves can be (when they're not mucky, cold puddles), the picture below (credit National Geographic channel) shows scientists perching on crystal spires in the Giant Cave of Crystals, underneath the Chihuahuan Desert, Mexico. The crystals, mostly gypsum, have grown so big largely because of the cave's internal temperature of ~58 celcius.


People have died in the past trying to get to the crystals, presumably for amoral purposes. It is a killer cave if unprepared and no mistake. The crevasses are sharp and deep; the heat would make popcorn out of your nuts were you exposed, if you haven't been cut to shreds beforehand.