Patterns of Mangrove Forest Structure and Soil Nutrient Dynamics along the Shark River Estuary, Florida

The Pearl River estuary is an ecologically dynamic region located in southern China that experiences strong gradients in its biogeochemical properties. This study examined the seasonality of nutrient dynamics, identified related environmental responses, and evaluated how river discharge regulated nutrient sink and source. The field investigation showed significant differences of dissolved nutrients with seasons and three zones of the estuary regarding the estuarine characteristics. Spatially, nutrients exhibited a clear decreasing trend along the salinity gradient; temporally, their levels were obviously higher in summer than other seasons. The aquatic environment was overall eutrophic, as a result of increased fluxes of nitrogen and silicate. This estuary was thus highly sensitive to nutrient enrichment and related pollution of eutrophication. River discharge, oceanic current, and atmospheric deposition distinctly influenced the nutrient status. These factors accordingly may influence phytoplankton that are of importance in coastal ecosystems. Phytoplankton (in terms of chlorophyll) was potentially phosphate limited, which then more frequently resulted in nutrient pollution and blooms. Additionally, the nutrient sources were implied according to the cause–effect chains between nutrients, hydrology, and chlorophyll, identified by the PCA-generated quantification. Nitrogen was constrained by marine-riverine waters and their mutual increase-decline trend, and a new source was supplemented along the transport from river to sea, while a different source of terrestrial emission from coastal cities contributed to phosphate greatly.

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Soil Nutrient Dynamics and Nitrogen Fixation Rate Changes over Plant Growth in Temperate Soil

Agronomy ◽

10.3390/agronomy9040179 ◽

2019 ◽

Vol 9 (4) ◽

pp. 179 ◽

Cited By ~ 4

Author(s):

Ágota Horel ◽

Györgyi Gelybó ◽

Imre Potyó ◽

Klára Pokovai ◽

Zsófia Bakacsi

Keyword(s):

Nitrogen Fixation ◽

Nutrient Dynamics ◽

Plant Biomass ◽

Soil Nutrient ◽

Initial Increase ◽

Pepper Plant ◽

Plant Interactions ◽

Fixation Rate ◽

Total N ◽

Fiber Sludge

Research on the use of soil enhancer materials such as biochar from soil chemical perspective still provide differing results; therefore, investigations focusing on soil-biochar-plant interactions are still necessary to constrain our understanding of complex biochar effects. The present study investigated the changes in biological nitrogen fixation rates (BNF) and overall nutrient dynamics (NO3−, NH4+, total N, K2O, and P2O5) during the growth of Capsicum annuum (pepper) in pot experiments amended with biochar made of paper fiber sludge and grain husk. Four treatments were studied with 0, 0.5%, 2.5%, and 5.0% (by weight) added biochar (BC) amount to temperate silt loam soil. Peppers were planted at 2–4 leave stages and grown for the duration of 12.5 weeks. Our results showed that total nitrogen had relatively small changes in all treatments over time compared to the dynamic changes observed in the case of inorganic nutrients. NO3−-N and NH4+-N abundances presented a continuous decrease during the course of the study after an initial increase. The pepper plant facilitated the BNF rates to triple in the control soils, while plants were in the growing phase (weeks 1–6), which further increased an additional 61% by harvesting (week 12). A high amount of biochar addition suppressed potential BNF rates of the investigated soil, indicating its potentially negative effects on soil indigenous microbial communities if added in excess. We also found a plateau in plant biomass production that after reaching an optimal (2.5%) biochar amendment in the soils, and excess biochar addition did not result in significant changes in the soils’ pH to achieve better nutrient (potassium, nitrogen, phosphorous) use or crop growth.

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Nutrient Dynamics in an Avicennia marina (Forsk.) Vierh., Mangrove Forest in Vamleshwar, Gujarat, India

Notulae Scientia Biologicae ◽

10.15835/nsb315594 ◽

2011 ◽

Vol 3 (1) ◽

pp. 51-56 ◽

Cited By ~ 4

Author(s):

Isaiah Nirmal KUMAR ◽

Poliyaparambil Ravi SAJISH ◽

Rita Nirmal KUMAR ◽

George BASIL ◽

Viyol SHAILENDRA

Keyword(s):

Mangrove Forest ◽

Nutrient Dynamics ◽

Tree Height ◽

Nutrient Budget ◽

Avicennia Marina ◽

Fall Rate ◽

Litter Fall ◽

Turnover Rates ◽

Nutrient Use ◽

One Year

The study was carried out to determine the nutrient budget of plants, sediments and nutrient dynamics in an Avicennia marina (Forsk.) Vierh., dominated forest in Vamleshwar near Narmada estuary, West Coast of Gujarat for a period of one year from November 2008 to October 2009. The average tree height of the mangrove is 1.5 to 2 m without much vertical stratification. Allometric methodology was used to measure the biomass, and yield a figure of 86.47 t ha-1 and the litter fall rate amounted to 2.9 t ha-1. Nutrient stocks of N, P and K in this mangrove were 137.05, 14.38 and 241.29 kg ha-1, with an annual accumulation of 55.74, 12.38 and 83.94 kg ha-1, and an annual return of 51.30, 10.83 and 13.52 kg ha-1, respectively, in the form of litter. The annual uptake for N, P and K were 61.04, 14.28 and 97.46 kg ha-1, and turnover rates of N, P and K were estimated at 3, 6 and 14 years, respectively, for the study period. Flow coefficients, which reveal the dynamic processes of nutrients between mangrove plants and sediments, are also explained. The present study concluded that the A. marina dominated mangrove plantation is more efficient in nutrient use and conservation.

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