First define your type of production gross production as rate of gross carbon fixation , net production the balance between carbon fixation and respiration and community production the difference between net production and loss from grazers, sediment burial and net to the water column by net resuspension, the loss back to the local sediments then being a function of subsequent loss from the water column though grazing and advection from the local water column and so on. Do a diagram of your appropriate in and out puts for your system. Then start by looking at the rate of new nutrient availability and the recycled nutrients from the sediments as an indication of any changes in the efficiency of using all new nutrient supply. That is supply from both the river and the sea

Light becomes the the usual function of depth, river Weston and resuspended and waterborne autochthonous load. It's all quite messy if youse this systems modelling approach.

Otherwise use a simple predictive model like vollrnvieders approach by taking data from. Range of different systems and normalising the batboy metric and residence time parameters for a general model

Good luck.

thank you John and Nicolas

The answers is so open, The microbenthic production depend of a lot of factors, the depth, which I mean the "light which soil receive". The original conditions of the soil, the nutrients, the dry period of the soil, the organic matter contribution, You need to define, the environment you are talking about, It is different magrove soil from beach ones, lakes or river ones. but I think mainly nutrients, light depth and fluid wáter are the manily factors as physicial conditions you need to consider. But, on the other hand, also the presence of consumer is important

Microphyto benthos are microscopic, photosynthetic eukaryotic algae and cyanobacteria on the sea floor. And production by this benthos is strongly determined by variable light intensities reaching the ocean floor and their response to the quality of irradiance pervading the water column.

Change in tide i.e. low tide and resuspension (diel movements) of these organisms in the water is are secondary determining factors for the access these organisms to light.

@Nicolas: From mudflat!

@Azubuike: I do not think that there is any microphytobenthos existing on the ocean floor!

@Dola by ocean floor i meant shallow areas of marine habitats that have access to light like where the coral reefs occupy i.e. continental shelf.

It would be great if someone gets me literature on the influence of sediment type (or grain size) on the distribution or assemblage pattern of microphytobenthos.

Hi , Dola Bhattacharjee

Several factors controls the diversity, distribution of microphytobenthos in a particular area say for example sediment grain size, available organic carbon, overlaying water salinity and temperature, natural suspended sediment loads influence light penetration and ambient primary production, local currents that affect the sediment grain size and food availability for filter feeders as well as other factors. Generally shallow areas are influenced by numerous factors on a daily and even hourly basis from changing tides, currents, salinity, and associated factors. Although the deeper or off shore are not exposed to such dramatic changes with time. Many of these natural perturbations are lead to pronounced gradients the biomass, density and diversity of estuarine microphytobenthic communities.

Have a look here some related literature on the influence of sediment on the distribution/ assemblage pattern of microphytobenthos.

1) Maclntyre et al., 1996. Microphytobethos: the ecological role of the secret garden un-investigated shallow water marine habitats. Distribution abundance and primary production. Estaries 19: 186-201

2) Jesus, B., Mendes, C.R., Brotes, V., Paterson, D.M., (2006), Effects of sediment type on microphytobenthos vertical distribution. Expermental Marine biolog y and ecology 332: 60-74

3) Jesus, B., Brotes, V., Ribeiro, L., Mendes, C.R., Cartaxana, P., and Paterson, D.M., (2009), Adaptations of microphytobenthos assemblages to sediment type and tidal position, Continental Shelf Research 29: 1624-1634.

Hi

Article An Update on the Global Stressors and Constraints Affecting ...

The following factors control the microphytobenthos production:

Sediment texture, salinity and grain size