Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. ...Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. The dynamics of AM fungi with desert ephemerals were examined to determine the effects of host plant life stages on the development of AM fungi. Mean colonization of ephemeral annual plants was 45% lower than that of ephemeral perennial plants. The colonizations were much higher in the early part of the growing season than in later parts, peaking at flowering times. The phenology of AM fungi in root systems varied among different ephem- erals. The density of AM fungal spores increased with the development of ephemeral annual plants, reached its maximum at flowering times, and then plateaued about 20 days after the aboveground senescence. A significant positive correlation was found between AM fungi spore density and biomass of ephemeral annual plants. The life cycles of AM fungi associated with desert ephemerals were very shod, being about 60-70 days. Soil temperature and water content had no direct influence on the development of AM fungal spores. We concluded that the development of AM fungi was in response to desert ephemeral phenology and life history strategy.展开更多
Grain to Green program on arable land has been conducted for decades in semi-arid regions of North China.However,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation...Grain to Green program on arable land has been conducted for decades in semi-arid regions of North China.However,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation types,i.e.shrubland(SL)and woodland(WL),and the adjacent cropland(CL)were investigated to determine afforestation effects on SHP in this area.Disturbed and undisturbed soil cores were collected in three experimental sites.Soil field capacity(FC),wilting point(WP),and available water capacity(AWC)increased in SL compared to the CL.Soil saturated water content,however,decreased significantly in both SL and WL.Correlation and redundancy analysis identified that bulk density(BD)and soil organic carbon(SOC)were the main factors regulating SHP across different land uses.Lower saturated water contents in afforestation sites were likely driven by the higher BD,compared to the adjacent cropland.FC,WP,and AWC were positively correlated to SOC content.While afforestation may not increase the saturated water content of a landscape,our results indicate that it can improve soil water retention and could be an effective practice for soil and water conservation.展开更多
目的:探究第2.1版前列腺影像报告与数据系统(prostate imaging reporting and data system,PI-RADS v2.1)联合前列腺特异抗原(prostate specific antigen,PSA)、前列腺特异抗原密度(prostate specific antigen density,PSAD)在前列腺癌(...目的:探究第2.1版前列腺影像报告与数据系统(prostate imaging reporting and data system,PI-RADS v2.1)联合前列腺特异抗原(prostate specific antigen,PSA)、前列腺特异抗原密度(prostate specific antigen density,PSAD)在前列腺癌(prostate cancer,PCa)诊断中的应用价值。方法:选择2016年5月—2021年6月于南通市第二人民医院进行治疗的90例疑似前列腺癌患者作为研究对象。90例患者分别进行多参数核磁共振(mp-MRI)检查,对患者的前列腺图像进行PIRADS v2.1评分及PI-RADS v2.1评分联合PSA、PSAD诊断。以患者前列腺穿刺取组织进行病理检查结果为金标准,分析患者的PSA、PSAD水平及PI-RADS v2.1评分联合PSA、PSAD对前列腺癌的敏感度、特异度、阳性预测值和阴性预测值。结果:90例疑似PCa患者,病理学诊断结果:恶性肿瘤42例,良性肿瘤48例。良性患者和恶性患者游离前列腺特异性抗原(f-PSA)对比,差异无统计学意义(P>0.05),良性患者PSAD、总前列腺特异性抗原(t-PSA)低于恶性肿瘤,f-PSA/t-PSA高于恶性肿瘤,差异均有统计学意义(P<0.05)。PI-RADS v2.1评分联合PSA、PSAD诊断准确率高于PI-RADS v2.1评分,差异有统计学意义(P<0.05)。PI-RADS v2.1评分联合PSA、PSAD检测的敏感度、特异度、阳性预测值、阴性预测值均高于PI-RADS v2.1评分,差异均有统计学意义(P<0.05)。结论:对前列腺癌患者的诊断中,PI-RADS v2.1评分具有较高的准确性,但PI-RADS v2.1评分联合PSA、PSAD检测在敏感度、特异度和准确度更有参考价值。展开更多
基金funded by the National Natural Science Foundation of China (30770341)the International Fund for Agricultural Development (the WATERCOPE project,I-R-1284)
文摘Previous studies documented that most desert plants can be colonized by arbuscular mycorrhizal （AM） fungi, however, little is known about how the dynamics of AM fungi are related to ephemerals in desert ecosystems. The dynamics of AM fungi with desert ephemerals were examined to determine the effects of host plant life stages on the development of AM fungi. Mean colonization of ephemeral annual plants was 45% lower than that of ephemeral perennial plants. The colonizations were much higher in the early part of the growing season than in later parts, peaking at flowering times. The phenology of AM fungi in root systems varied among different ephem- erals. The density of AM fungal spores increased with the development of ephemeral annual plants, reached its maximum at flowering times, and then plateaued about 20 days after the aboveground senescence. A significant positive correlation was found between AM fungi spore density and biomass of ephemeral annual plants. The life cycles of AM fungi associated with desert ephemerals were very shod, being about 60-70 days. Soil temperature and water content had no direct influence on the development of AM fungal spores. We concluded that the development of AM fungi was in response to desert ephemeral phenology and life history strategy.
基金financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA23090403)the National Key Research and Development Program of China(Grant No.2019YFD1100503)the National Major Science and Technology Program for Water Pollution Control and Treatment(Grant No.2017ZX07101001)。
文摘Grain to Green program on arable land has been conducted for decades in semi-arid regions of North China.However,it remains uncertain how afforestation practices affect soil hydraulic properties(SHP).Two afforestation types,i.e.shrubland(SL)and woodland(WL),and the adjacent cropland(CL)were investigated to determine afforestation effects on SHP in this area.Disturbed and undisturbed soil cores were collected in three experimental sites.Soil field capacity(FC),wilting point(WP),and available water capacity(AWC)increased in SL compared to the CL.Soil saturated water content,however,decreased significantly in both SL and WL.Correlation and redundancy analysis identified that bulk density(BD)and soil organic carbon(SOC)were the main factors regulating SHP across different land uses.Lower saturated water contents in afforestation sites were likely driven by the higher BD,compared to the adjacent cropland.FC,WP,and AWC were positively correlated to SOC content.While afforestation may not increase the saturated water content of a landscape,our results indicate that it can improve soil water retention and could be an effective practice for soil and water conservation.
