Differences in biomass and silica content in typical plant communities with ecotones in the Min River estuary of southeast China

Abstract

Silica (Si) is a basic nutrient requirement for many aquatic organisms and its biogeochemical cycle plays an important role in estuarine coastal ecosystems. However, little is known about the role Si plays during plant–plant interactive processes in the marsh ecosystems. Here, variations in biomass, biogenic silica (BSi) content, and available Si content of Cyperus malaccensis-dominated marshes, Phragmites australis-dominated marshes, and their ecotonal marshes were studied in the Shanyutan marsh in the Min River estuary, China. Results showed that C. malaccensis and P. australis biomass in ecotones was lower than those in typical communities by 46.4% and 46.3%, respectively. BSi content in aboveground organs of C. malaccensis and culms and roots of P. australis was lower in ecotones than in typical communities, whereas BSi content in other organs showed the opposite trend. Biomass allocation in C. malaccensis and P. australis roots in ecotones was higher by 56.9% and 19.5%, respectively, and BSi stock in C. malaccensis and P. australis roots was higher than that in typical communities by 120.9% and 18.9%, respectively. Available Si content in ecotonal marsh soils was 12.6% greater than that in typical communities. Thus, the two plant species may use different strategies for Si accumulation and allocation in ecotones to adapt to the competitive environment. P. australis may expand primarily via occupation of wider aboveground space, thereby increasing the Si accumulation capacity in aboveground organs. Meanwhile, C. malaccensis may increase the Si allocation capacity of its roots to withstand the pressure from P. australis. This study will provide new insights into marsh plant competition from the perspective of Si, which can also benefit plant management in marsh ecosystems.

Phytolith-Occluded Carbon Sequestration Potential of Oil Palm Plantation in Tamil Nadu

“…The Si estimation was performed using ICP-OES and the extraction of phytolith was carried out through microwave digestion. 8 The extract was dried in an oven at 65 °C for 48 h and weighed. A 0.8 M Potassium dichromate (K 2 Cr 2 O 7 ) solution was used to detect the organic content bound to the phytolith, and the alkali spectrophotometric method was used for estimating PhytOC.…”

“…The soil samples were dried and ground for physicochemical analysis (Table ). The collected parts were thoroughly washed with deionized water and kept in the hot air oven (48 h @ 60 °C) for attaining constant weight . The plant samples were dried at 70 °C for 48 h and ground (0.25 mm) for further analysis.…”

“…It provides rigidity, enhances resistance to plant abiotic−biotic stresses, and influences element cycling during litter decomposition. 8 The accumulation of intercellular and extracellular phytoliths in the plant parts is aided by the systemʼs evaporation and water transportation. Generally, phytoliths are highly stable and possess distinctive shapes with varied dimensions (20−200 μm).…”

“…Although Si is not considered a crucial element for plant growth, it has multiple beneficial effects, which include development, yield, mineral nutrition, health, and survival of plant species for decades in agricultural ecosystems. It provides rigidity, enhances resistance to plant abiotic–biotic stresses, and influences element cycling during litter decomposition . The accumulation of intercellular and extracellular phytoliths in the plant parts is aided by the systemʼs evaporation and water transportation.…”

Dynamics and characteristics of biogenic silica and macro- and microelements in decomposing litter in the Min River estuary, southeast China

“…The marsh sediment in this area is dominated by saline soil, and the main vegetation species include PA, CM, and SA from the seawall to the sea. More detailed descriptions of the sites are provided by Tong et al (2011) and Gao et al (2019).…”