Conversion of drylands to paddy fields on former wetlands restores soil organic carbon by accumulating labile carbon fractions in the Sanjiang Plain, northeast China.

Background: Since the 1990s, drylands have been extensively converted to rice paddy fields on the former wetlands in the Sanjiang Plain of northeast China. However, the influence of this successiveland-use change from native wetlands to drylands to rice paddy fields on soil organic carbon (C) dynamics remains unexplored. Here, we compared the difference in soil organic C stock among native wetlands, drylands, and paddy fields, and then used a two-step acid hydrolysis approach to examine the effect of this land-use change on labile C I (LPI-C), labile C II (LPII-C), and recalcitrant C (RP-C) fractions at depths of 0-15 cm, 15-30 cm, and 30-50 cm.

Response of individual sizes and spatial patterns of Deyeuxia angustifolia to increasing water level gradient in a freshwater wetland.

The wetland plants are very sensitive to hydrological regimes. In this study, the individual sizes of a widely distributed species (i.e.

[Difference in intra- and inter-specific competition of two endangered plant species (Toona ciliate var. pubescens and Taxus chinensis var. mairei)in the middle subtropical zone of China].

Endangered plant species are an important part of global biodiversity. To understand the competition patterns and mechanisms of endangered tree species from plant growth forms in the middle subtropical forest ecosystems, we examined the differences in intra- and inter-specific competitions between Toona ciliate var. pubescens (an intolerant of shade, deciduous species) and Taxus chinensis var.

Alnus sibirica encroachment promotes dissolved organic carbon biodegradation in a boreal peatland.

Symbiotic dinitrogen (N)-fixing trees have been expanding to boreal peatlands, yet its influence on dissolved organic carbon (DOC) biodegradation is unclear. Here, we measured DOC, ammonium‑nitrogen (NH-N), nitrate‑nitrogen (NO-N), dissolved inorganic nitrogen (DIN), and dissolved total nitrogen (DTN) concentrations, specific ultraviolet absorbance at 254 nm (SUVA), and humification index in the extracts obtained from peats in the 0-10 cm, 10-20 cm, and 20-40 cm depths in the open peatlands and Alnus sibirica islands in a boreal peatland, Northeast China. Afterwards, the peat extracts were used to assess the effect of N-fixing woody plant expansion on DOC biodegradation with a 42-day incubation experiment.

Effects of P addition on plant C:N:P stoichiometry in an N-limited temperate wetland of Northeast China.

Phosphorus (P) enrichment induced by anthropogenic activities results in modified plant nutrient status, which potentially alters the stoichiometry of carbon (C), nitrogen (N), and P in plants. However, how increased P availability changes plant C:N:P stoichiometry at different hierarchical scales is unclear in N-limited ecosystems. In this study, we conducted a four-level P addition experiment (0, 1.

[Capsule endoscopic diagnosis and treatment with intraoperative endoscopic assistance of vascular malformation of small intestine with bleeding].

Objective: To evaluate the effect of capsule endoscopic examination in the diagnosis of vascular malformation of small intestine and discuss the operative method of this disease.

Methods: The clinical data of 11 cases of vascular malformation of small intestine by the capsule endoscopic diagnosis were analyzed retrospectively.

Results: All of the 11 cases received operation with the assistance of intra-operative endoscopic examination, and 10 cases were confirmed to suffer from vascular malformation of small intestine postoperatively.