A field study on groundwater dynamics in a salt marsh - Chongming Dongtan wetland

Subsurface hydrology plays an important role in governing the behaviour of salt marshes, in particular, nutrient exchange, plant zonation and carbon cycling. The objective of this paper is to examine the hydrological characteristics of a salt marsh based on a field investigation conducted at a cross-creek section in the Chongming Dongtan wetland (Shanghai, China). Field measurements showed complex groundwater table fluctuations, controlled by multiple factors. The groundwater table near the creek responded quickly to the creek water level fluctuation, in contrast with the weak water table response in the marsh interior. The average elevation of the groundwater table near the creek was lower than that in the interior, suggesting that the optimal soil aeration condition occurred near the creek. The variations of pore water salinity along the cross-creek transect also appeared to be complex even though a low salinity zone remained present near the creek levee over the investigation period. Relatively strong pore water circulation near the creek prevented local solute accumulation. These results are essentially consistent with the hypothesis that the area near the creek is better suited for plant growth. In the marsh interior, weakened drainage and flushing effects may leave the soil largely saturated for a long period and suppress carbon exchange between the marsh soil and ambient environments (coastal water and atmosphere)

Ion Flux in Roots of Chinese Fir (Cunninghamia lanceolata (Lamb.) Hook) under Aluminum Stress.

Chinese fir is a tall, fast-growing species that is unique to southern China. In Chinese fir plantations, successive plantings have led to a decline in soil fertility, and aluminum toxicity is thought to be one of the main reasons for this decline. In this study, Non-invasive Micro-test Technology was used to study the effect of aluminum stress on the absorption of 4 different ions in the roots of the Chinese fir clone FS01. The results are as follows: with increased aluminum concentration and longer periods of aluminum stress, the H+ ion flow gradually changed from influx into efflux; there was a large variation in the K+ efflux, which gradually decreased with increasing duration of aluminum stress; and 1 h of aluminum stress uniformly resulted in Ca2+ influx, but it changed from influx to efflux after a longer period of aluminum stress. Changes in the different concentrations of aluminum had the largest influence on Mg2+

Genome-Wide Identification, Expression Pattern Analysis and Evolution of the Ces/Csl Gene Superfamily in Pineapple (Ananas comosus)

The cellulose synthase (Ces) and cellulose synthase-like (Csl) gene families belonging to the cellulose synthase gene superfamily, are responsible for the biosynthesis of cellulose and hemicellulose of the plant cell wall, and play critical roles in plant development, growth and evolution. However, the Ces/Csl gene family remains to be characterized in pineapple, a highly valued and delicious tropical fruit. Here, we carried out genome-wide study and identified a total of seven Ces genes and 25 Csl genes in pineapple. Genomic features and phylogeny analysis of Ces/Csl genes were carried out, including phylogenetic tree, chromosomal locations, gene structures, and conserved motifs identification. In addition, we identified 32 pineapple AcoCes/Csl genes with 31 Arabidopsis AtCes/Csl genes as orthologs by the syntenic and phylogenetic approaches. Furthermore, a RNA-seq investigation exhibited the expression profile of several AcoCes/Csl genes in various tissues and multiple developmental stages. Collectively, we provided comprehensive information of the evolution and function of pineapple Ces/Csl gene superfamily, which would be useful for screening out and characterization of the putative genes responsible for tissue development in pineapple. The present study laid the foundation for future functional characterization of Ces/Csl genes in pineapple

The effects of aluminum stress on Mg²⁺ flux in Chinese fir roots.

<p>The effects of aluminum stress on Mg²⁺ flux in Chinese fir roots.</p

The effects of aluminum stress on Ca²⁺ flux in Chinese fir roots.

<p>The effects of aluminum stress on Ca²⁺ flux in Chinese fir roots.</p

Effect of aluminum toxicity on the relative root elongation of Chinese fir.

<p>Effect of aluminum toxicity on the relative root elongation of Chinese fir.</p

Genetic diversity and variation of Chinese fir from Fujian province and Taiwan, China, based on ISSR markers

<div><p>Genetic diversity and variation among 11 populations of Chinese fir from Fujian province and Taiwan were assessed using inter-simple sequence repeat (ISSR) markers to reveal the evolutionary relationship in their distribution range in this report. Analysis of genetic parameters of the different populations showed that populations in Fujian province exhibited a greater level of genetic diversity than did the populations in Taiwan. Compared to Taiwan populations, significant limited gene flow were observed among Fujian populations. An UPGMA cluster analysis showed that the most individuals of Taiwan populations formed a single cluster, whereas 6 discrete clusters were formed by each population from Fujian. All populations were divided into 3 main groups and that all 5 populations from Taiwan were gathered into a subgroup combined with 2 populations, Dehua and Liancheng, formed one of the 3 main groups, which indicated relative stronger relatedness. It is supported by a genetic structure analysis. All those results are suggesting different levels of genetic diversity and variation of Chinese fir between Fujian and Taiwan, and indicating different patterns of evolutionary process and local environmental adaption.</p></div

The structure of the Chinese fir root.

<p>The structure of the Chinese fir root.</p