The distribution of vegetation in coastal wetlands is significantly influenced by soil properties. However, the mechanisms of how soil characteristics impact the physiological processes of forests remain underexplored. This study examined changes in the soil physicochemical properties and structural attributes of natural forests in the Yellow River Delta with increasing distance from the shoreline.
View Article and Find Full Text PDFAn important indicator of forest dynamics is the forest community turnover rate, which was defined as the relative change in a variable of interest (e.g., basal area or stem abundance) to its maximum or total in the community over a certain period.
View Article and Find Full Text PDFRobinia pseudoacacia is the main arbor species in the coastal saline-alkali area of the Yellow River Delta. Because most studies focus on the aboveground parts, detailed information regarding root functioning under salinity is scare. Root traits of seedlings of R.
View Article and Find Full Text PDFVariations of plant C: N: P stoichiometry could be affected by both some environmental fluctuations and plant physiological processes. However, the trade-off mechanism between them and their influencial factors were not understood completely. In this study, C, N, P contents and their stoichiometry of S.
View Article and Find Full Text PDFDifferences among tropical tree species in survival and growth to light play a key role in plant competition and community composition. Two canopy species with contrasting functional traits dominating early and late successional stages, respectively, in a tropical montane rain forest of Hainan Island, China, were selected in a pot experiment under 4 levels of light intensity (full, 50%, 30%, and 10%) in order to explore the adaptive strategies of tropical trees to light conditions. Under each light intensity level, the pioneer species, Endospermum chinense (Euphorbiaceae), had higher relative growth rate (RGR), stem mass ratio (SMR), specific leaf area (SLA), and morphological plasticity while the shade tolerant climax species, Parakmeria lotungensis (Magnoliaceae), had higher root mass ratio (RMR) and leaf mass ratio (LMR).
View Article and Find Full Text PDFEffects of age and stand density of mother tree on seed germination, seedling biomass allocation, and seedling growth of Pinus thunbergii were studied. The results showed that age of mother tree did not have significant influences on seed germination, but it was significant on seedling biomass allocation and growth. Seedlings from the minimum and maximum age of mother tree had higher leaf mass ratio and lower root mass ratio than from the middle age of mother tree.
View Article and Find Full Text PDFBy using eddy covariance technique, this paper measured the net ecosystem CO2 exchange (NEE) in a reed (Phragmites australis) wetland in the Yellow River Delta of China during the growth season of 2011, and investigated the variation patterns of the NEE and related affecting factors. The average diurnal variation of the NEE in different months showed a U-type curve, with the maximum net CO2 uptake rate and release rate being (0.44 +/- 0.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
August 2012
Based on the investigation of the gale-caused damage to the Robinia pseudoacacia plantation in the Yellow River Delta in June-July 2010, this paper measured the morphological indexes and root system characteristics of fallen trees, gap sizes, and soil compactness, aimed to analyze the formation causes of the wind damage to the plantation. Wind-falling was the main form of the wind damage to the R. pseudoacacia plantation, and the damage was more serious for the trees with the diameter at breast height of 15-20 cm.
View Article and Find Full Text PDFVegetation type and density exhibited a considerable patchy distribution at very local scales in the Yellow River Delta, due to the spatial variation of soil salinity and water scarcity. We proposed that soil respiration is affected by the spatial variations in vegetation type and soil chemical properties and tested this hypothesis in three different vegetation patches (Phragmites australis, Suaeda heteroptera and bare soil) in winter (from November 2010 to April 2011). At diurnal scale, soil respiration all displayed single-peak curves and asymmetric patterns in the three vegetation patches; At seasonal scale, soil respiration all declined steadily until February, and then increased to a peak in next April.
View Article and Find Full Text PDFYing Yong Sheng Tai Xue Bao
February 2011
Based on the 23 sheets of remote sensing images from 1976 to 2009, in combining with the water and sediment data from Lijin station and the annual precipitation data of Yellow River Basin from 1976 to 2008, this paper quantitatively analyzed the features of water and sediment discharge from Yellow River, and the evolution process of Yellow River Delta and related driving mechanisms. In 1976-2008, the annual runoff and the annual sediment discharge into sea changed largely and frequently, but overall, presented a decreasing trend. Since the course of the Yellow River changed its direction to Qingshui channel in 1976, the Delta coastline and area were generally in a silting-up state.
View Article and Find Full Text PDFWell-understand the organic carbon status in the Yellow River delta is the most important for studying the biogeochemical processes of the muddy-sandy coastal wetland and ecological restoration. The spatial distribution characteristics and its impact factors of organic carbon in the plant-soil systems of new-born tidal flat wetland in the Yellow River estuary were studied. The results showed that the difference of plant organic carbon content in different plant communities were not obvious, however significant difference of the plant organic carbon density was observed.
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