Characteristics and provenances of rare earth elements and Nd isotopes in surface sediments of mangrove wetlands in the Jiulong River Estuary, China.

Rare earth elements (REEs) and Nd isotopes are frequently employed to determine provenance, although their characteristics and provenances in the surface sediments of mangrove wetlands are rarely analyzed. In this study, a thorough analysis of the characteristics and provenances of REEs and Nd isotopes in the surface sediments of mangrove wetland in the Jiulong River Estuary was carried out. According to the results, the mean concentration of REEs in the surface sediments was 290.

Response of phenolic metabolism to cadmium and phenanthrene and its influence on pollutant translocations in the mangrove plant Aegiceras corniculatum (L.) Blanco (Ac).

Polyphenolic compounds are abundant in mangrove plants, playing a pivotal role in the detoxification of pollutants extruded from surrounding environments into plant tissues. The present study aimed to examine the variations of phenolic compounds, namely total polyphenolics, soluble tannins, condensed tannins and lignin, in the mangrove plant Aegiceras corniculatum (L.) due to the presence of exogenous cadmium and phenanthrene and to explore the influence of phenolic metabolism on biological translocation of these pollutants from roots to leaves.

pH regulates ammonia-oxidizing bacteria and archaea in paddy soils in Southern China.

Ammonia-oxidizing archaea (AOA) and bacteria (AOB) play important roles in nitrogen cycling. However, the effects of environmental factors on the activity, abundance, and diversity of AOA and AOB and the relative contributions of these two groups to nitrification in paddy soils are not well explained. In this study, potential nitrification activity (PNA), abundance, and diversity of amoA genes from 12 paddy soils in Southern China were determined by potential nitrification assay, quantitative PCR, and cloning.

Nitrogen loss by anaerobic oxidation of ammonium in rice rhizosphere.

Anaerobic oxidation of ammonium (anammox) is recognized as an important process for nitrogen (N) cycling, yet its role in agricultural ecosystems, which are intensively fertilized, remains unclear. In this study, we investigated the presence, activity, functional gene abundance and role of anammox bacteria in rhizosphere and non-rhizosphere paddy soils using catalyzed reporter deposition-fluorescence in situ hybridization, isotope-tracing technique, quantitative PCR assay and 16S rRNA gene clone libraries. Results showed that rhizosphere anammox contributed to 31-41% N2 production with activities of 0.

Potential contribution of anammox to nitrogen loss from paddy soils in Southern China.

The anaerobic oxidation of ammonium (anammox) process has been observed in diverse terrestrial ecosystems, while the contribution of anammox to N2 production in paddy soils is not well documented. In this study, the anammox activity and the abundance and diversity of anammox bacteria were investigated to assess the anammox potential of 12 typical paddy soils collected in southern China. Anammox bacteria related to "Candidatus Brocadia" and "Candidatus Kuenenia" and two novel unidentified clusters were detected, with "Candidatus Brocadia" comprising 50% of the anammox population.

Alleviated toxicity of cadmium by the rhizosphere of Kandelia obovata (S., L.) Yong.

A pot experiment was conducted to investigate the Cadmium (Cd) toxicity alleviated by the rhizosphere of Kandelia obovata (S., L.) Yong (K.

Research on the nitrogen cycle in rhizosphere of Kandelia obovata under ammonium and nitrate addition.

The present study investigated nitrogen process in rhizosphere of Kandelia obovata under nitrogen input. Results showed that nitrogen additions significantly increased 4 kinds of enzyme activities (Urease, Nitrate reductase, Nitrite reductase and hydroxylamine reductase). The pH value increased to 7.

Kandelia obovata (S., L.) Yong tolerance mechanisms to Cadmium: subcellular distribution, chemical forms and thiol pools.

In order to explore the detoxification mechanisms adopted by mangrove under cadmium (Cd) stress, we investigated the subcellular distribution and chemical forms of Cd, in addition to the change of the thiol pools in Kandelia obovata (S., L.) Yong, which were cultivated in sandy culture medium treated with sequential Cd solution.

The short-term effect of cadmium on low molecular weight organic acid and amino acid exudation from mangrove (Kandelia obovata (S., L.) Yong) roots.

The aim of this study was to evaluate short-term concentration and time effects of cadmium on Kandelia obovata (S., L.) Yong root exudation, thereby evaluating and predicting the ecophysiological effects of mangrove to heavy metals at the root level.