The flow of power via any type of ecosystem starts with the fixation of sunlight by plants and other autotrophic organisms. In this way the plant accumulates energy and this energy is dubbed primary production. The rate at which this power accumulates is called main productivity. The full energy gathered is gross major production, however, because plants use some of this energy themselves, it is not all easily accessible for the food internet. The distinction between what is accumulated and also what is available for the food internet is referred to as net major production expressed in

kilocalories or grams m-2 y-1 or kcal or g/m2/y. This is measured by sequentially measuring growth of the biomass over time by marking the plants someexactly how, or measuring a full at the end of the thriving seachild. Alternatively you can meacertain oxygen manufacturing or CO2 consumption both of which equal grams C developed. (experiment possiblities!)

In general, swamps and also marshes have actually the highest main manufacturing of all the world"s ecounits. Main production of all wetland kinds varies from 600-2000 gC/m2/y.

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To testimonial a little:

In general, the "openness" of a wetland also to hydrological fluxes is probably among the the majority of essential components of main effisteustatiushistory.orgency. So wetlands that are stagnant are much less productive than those that steustatiushistory.orgrculation or are open up to flooding rivers. This renders feeling bereason a flow-with system constantly gets even more nutrients. This isn"t 100% though bereason wetlands acquire the majority of of their nutrients from recycling fairly than from the outside. This is what enables them all to be reasonably productive.

Salt Marshes:

These tend to be the most productive ecosystems in the people. Price quotes of the southerly simple of the U.S. have actually topped 8000 gC/m2/y via the combined efforts of marsh grass, mud algae, and also phytoplankton in the tidal creeks. The southerly marshes execute much better than the north ones partly bereason of the higher influx of solar power and also longer thriving seakid, and partly because of the nutrient wealthy sediments brought by rivers in that region.

Low or intertidal marshes are even more fertile than high marshes bereason of the raised exposure to tidal flow.

Belowground production is high. Under unfavorable soil problems, plants seem to put more energy right into root production. (experiment possibility!)

Usually, plant manufacturing relies on light, water, nutrients, and toxins. If you look at a salt marsh it has complete sunlight, unlimited water, and the sedimentary soil is mainly wealthy in nutrients so you"d suppose uniformly high production. That doesn"t happen:

1. Productivity declines northward as the growing season shortens.

2. Water looks numerous yet because it"s salty the plants tfinish to lose water and also so need to expend energy in order to take it up. It"s been displayed that plant expansion is significantly inhibited by salt (experiment possibility!)

3. The much less oxygen the soil contains, the worse the plants perform even if they"re adapted to make it through that, and salt marsh sediments tend to be low in oxygen.

Tidal Freshwater Marshes

Productivity is mostly high here (1000-3000 g/m2/y) however variable, depfinishing on:

1. Types of plants existing. Unlike salt marshes, freshwater tidal marshes have actually a wide diversity of plants and also so performance depends partially on how well the certain spesteustatiushistory.orges of plant grows.

2. Tidal power. Moving water mostly supports manufacturing.

3. Soil nutrients, grazing, and also toxins all have actually an impact.


Generally productivity is greatest in riverine mangroves and also lowest for dwarf mangroves (1100-5400 g/m2/y) Here again, the crusteustatiushistory.orgal appears to be the boosted nutrients gave by the tide.

Freshwater Marshes

Productivity in these is high, upward of 1000 g/m2/y. This is lower than what we"ve looked at so far, but still greater than that of strongly grew farm plants. It"s variable, aobtain bereason of the variety of plants that can be assosteustatiushistory.orgated. There"s a solid connection between above ground biomass and summer temperatures so southerly marshes are even more fertile than those in the north.


In these, a lot of the manufacturing is below ground and also mosses, particularly Sphagnum , account for 1/3-1/2 the full manufacturing.

These wetlands are much much less fertile and also other wetlands and also are primarily much less abundant than terrestrial ecounits in the very same areas (250-500 g/m2/y)

Cypress Swamps

As shown in the figure, the highest possible productivity in cypush swamps appears to occur once conditions are neither also wet nor too dry and tright here is seasonal pulsing. The even more water that flows through, the much better. Even so, these are much less abundant than marshes (500-1800 g/m2/y).

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(from Mitch and Gosseattach, 1993)

Riparian Wetlands

Remember that these are wetlands emerging along the edge of lakes and rivers. They are mainly even more fertile (600-1400 g/m2/y) than their nearby uplands due to:

1. Flooding offers suffisteustatiushistory.orgent water supplies

2. Nutrients are gave and favorable alteration of soil chemistry outcomes from the periodic overbank flooding (nitrification, sulfate reduction, nutrient mineralization--all these make the nutrients even more available to the plants)

3. Flowing water provides a more oxygenated root zone than if the water were stagnant. The "flushing" carries amethod waste products.