Phosphorus limitation induced by nitrogen addition changed soil microbial community structure in a subtropical forest.

Soil microorganisms play an important role in the biogeochemical cycles of terrestrial ecosystems. How-ever, it is still unclear how the amount and duration of nitrogen (N) addition affect soil microbial community structure and whether there is a correlation between the changes in microbial community structure and their nutrient limi-tation status. In this study, we conducted an N addition experiment in a subtropical forest to simulate N deposition with three treatments: control (CK, 0 kg N·hm·a), low N (LN, 40 kg N·hm·a), and high N (HN, 80 kg N·hm·a).

[Effects of different carbon addition modes on the soil priming effect of a subtropical forest under nitrogen deposition].

Priming effect (PE) plays an important role in regulating terrestrial soil carbon (C) cycling, but the impact of different C addition modes on the PE in subtropical forest ecosystems with increasing nitrogen (N) deposition is unclear. In this study, we investigated the effects of C addition patterns (single or repeated C addition) on soil PE by adding C-labeled glucose for 90 d in an incubation experiment with different levels of N application (0, 20, and 80 kg N·hm·a). The different patterns of glucose addition significantly increased soil organic C (SOC) mineralization and produced positive PE.

Enzyme stoichiometry evidence revealed that five years nitrogen addition exacerbated the carbon and phosphorus limitation of soil microorganisms in a forest.

The activity and stoichiometry of soil extracellular enzyme can provide a good indication for changes in soil nutrient availability and microbial demands for nutrients. However, it remains unclear how would nitrogen (N) deposition affect nutrient limitation of microbes in subtropical forest soils. We conducted a 5 years N addition experiment in a subtropical forest.

Evaluation of renal urothelial carcinoma by contrast-enhanced ultrasonography.

Purpose: To observe ultrasonographic features of urothelial carcinoma in renal pelvis and evaluate contrast-enhanced ultrasound (CEUS) in diagnosis.

Materials And Methods: Fifty-two patients with urothelial carcinoma underwent preoperative conventional US, colour Doppler flow imaging (CDFI) and CEUS.

Results: Of 52 total lesions, 41 (78.