Modeling Growth, Carbon Allocation and Nutrient Budgets of Phragmites australis in Lake Burullus, Egypt

Abstract

Phragmites australis is the major component of reed stands covering some 8200 ha along the shores of Lake Burullus (Egypt). We applied a published temperate zone reed model to assess growth and cycling of C and nutrients among the various organs of P. australis in this sub-tropical lake. We aim to quantify the role of reed stands for the C balance and nutrients cycling in the south Mediterranean wetland. Above-ground biomass was 3.5 times higher than the below-ground biomass. Root biomass represented 13% of the total below-ground, while leaves and panicles represented 16 and 3% of the above-ground biomass, respectively. Remobilization from rhizomes (15%) and reallocation from leaves (1%) were of little importance as assimilated sources. Nutrients accumulation by total aboveground biomass ranged between 2.7 to 46.8 gm −2 yr −1 for P and K, respectively. We calculated a C sequestration rate of 38.4 g C m −2 yr −1 for the dead rhizomes in the sediments. This value stresses the importance of P. australis stands for C sequestration in Lake Burullus. Further, as much as 254 t P and 5527 t N could potentially be removed annually from Lake Burullus by harvesting P. australis at maximum total above-ground biomass.

Verification of a numerical growth model of Pistia stratiotes L. using field data from tropical and subtropical sites

“…This finding is supported by our previous study on Eichhornia crassipes (Eid & Shaltout 2017), which indicated that the gross and net production of E. crassipes populations were higher in the tropical and sub-tropical regions than in the Nile Delta (Mediterranean region). Since biomass is often largely determined by specific habitat conditions (Luther 1983), the high biomass in the tropical and sub-tropical regions could be due to environmental factors that vary with latitude such as temperature, day length, solar irradiance, and length of growing season (Sand-Jensen 1989;Eid et al 2010Eid et al , 2013. Variation may also be partly attributed to biotic factors such as mutualists/facilitators or predators/pathogens.…”

Uptake of Ag, Co and Ni by the Organs of <i>Typha domingensis</i> (Pers.) Poir. ex Steud. in Lake Burullus and Their Potential Use As Contamination Indicators

“…Also it receives fish farms and industrial drainage water [18]. It is alkaline, shallow, brackish, and polluted lake [8]. The Mediterranean deltaic coast, in which this lake occurs, belongs to the arid region where the climatic conditions are warm summers (20˚C -30˚C) and mild winters (10˚C -20 ˚C).…”

“…Specifically, plants with potentially high annual primary production can extract large amounts of heavy metals from their environment and store these metals in biomass and litter [8]. Therefore, some aquatic plants such as Eichhornia crassipes (C.…”

Decomposition dynamics of Phragmites australis litter in Lake Burullus, Egypt

“…Reed beds, along the deltaic Mediterranean coast of Egypt, are important for wintering, foraging, refuge, and breeding of the migrant birds (Kassas 2002). Also, these stands probably play an important role in the nutrient budget of the Mediterranean coastal waters and lakes (Eid et al . 2010a,b).…”

“…1997), and it provides important information on wetland functioning (nutrient cycling and energy flow; Robinson & Gessner 2003). Phragmites australis occupies about 20% of Lake Burullus area (= 8200 ha) with a high primary production on the order of 54 t/ha (Eid et al . 2010b).…”