Effects of the Removal of Soil Extractable Oxytetracycline Fractions on Its Bioaccumulation in Earthworm and Horsebean     

Bao  Yanyu  Li  Yunxia  Pan  Chengrong 《Water, air, and soil pollution》2018,229(3):1-16

Water, Air, & Soil Pollution - The layered double hydroxides (LDHs) with a hydrotalcite-like structure are believed to possess great potentials as environmental remediation materials including...  相似文献   

Soil carbon and nutrient pools, microbial properties and gross nitrogen transformations in adjacent natural forest and hoop pine plantations of subtropical Australia   总被引：9，自引：8，他引：1  

Zhihong Xu  Sally Ward  Chengrong Chen  Tim Blumfield  Nina Prasolova  Juxiu Liu 《Journal of Soils and Sediments》2008,8(2):99-105

Background, Aims, and Scope  An improved understanding of important soil carbon (C) and nutrient pools as well as microbial activities in forest ecosystems is required for developing effective forest management regimes underpinning forest productivity and sustainability. Forest types and management practices can have significant impacts on soil C and nutrient pools as well as biological properties in forest ecosystems. Soil C and nutrient pools were assessed for adjacent natural forest (NF), first rotation (1R) (50-year-old), and second rotation (2R) (1-year-old) hoop pine (Araucaria cunninghamii Ait. ex D. Don) plantations in southeast Queensland of subtropical Australia. Materials and Methods  Five transects spaced 3 m apart with 9 sampling points along each transect were selected (9.6 m × 12.0 m each site), with 45 soil cores (7.5 cm in diameter) collected and separated into 0–10 and 10–20 cm depths. These soils were analysed for total C, total nitrogen (N), C (δ¹³C) and N (δ¹⁵N) isotope composition. The 0–10 cm soils were analysed for pH, CEC, exchangeable cations, total P and total K, and assayed for microbial biomass C and N, respiration, metabolic quotient, potential mineralizable N (PMN), gross N mineralization (M) and immobilization (I). Results  Total C and N in 0–10 cm soils were higher under NF and 1R plantation than under 2R plantation, while they were highest in 10–20 cm soils under NF, followed by the 1R and then 2R plantation. δ¹³C was lower under NF than under the plantations, while δ¹⁵N was higher under NF than under the plantations. Total P was the highest under NF, followed by the 1R and then 2R plantation, while total K was higher under the 2R plantation. No significant differences were detected for pH, CEC, exchangeable cations, microbial C and N, respiration and metabolic quotient among the 3 sites. PMN and M were higher under NF, while I was the highest under the 2R plantation, followed by the NF and then 1R plantation. Discussion  Soil total C and N in 0–10 cm depth were significantly lower under 2R hoop pine plantation than those under NF and 1R hoop pine plantation. There were significant reductions in soil total C and N from NF to 1R and from 1R to 2R hoop pine plantations in 10–20 cm depth. This highlights potential N deficiency in the 2R hoop pine plantations, and application of N fertilizers may be required to improve the productivity of 2R hoop pine plantations. There were no significant differences in other soil chemical and physical properties in 0–10 cm depth among the 3 sites under NF, 1R and 2R hoop pine plantations, except for soil total P and K. Soil microbial biomass C, CO₂ respiration and metabolic quotient did not differ among the 3 sites assessed, perhaps mainly due to these biological variables being too sensitive to variations in soil chemical and physical properties and thereby being associated with a larger variability in the soil biological properties. However, soil potential mineralizable N, gross N mineralization and immobilization were rather sensitive to the conversion of NF to hoop pine plantation and forest management practices. Conclusions  Total C and N in the top 20 cm soil were highest under NF, followed by 1R and then 2R hoop pine plantations, indicating that N deficiency may become a growth-limiting factor in the 2R hoop pine plantations and subsequent rotations of hoop pine plantation. The sample size for soil δ¹³C seems to be much smaller than those for soil total C and N as well as δ¹⁵N. The significant reductions in soil total P from NF to 1R and then from 1R to 2R hoop pine plantations highlight that P deficiency might become another growth-limiting factor in the second and subsequent rotations of hoop pine plantations. Soil microbial properties may be associated with large spatial variations due to these biological properties being too sensitive to the variations in soil chemical and physical properties in these forest ecosystems. Recommendations and Perspectives  Soil potential mineralizable N, gross N mineralization and immobilization were useful indices of soil N availability in response to forest types and management practices. The sampling size for soil δ¹³C was much smaller than the other soil chemical and biological properties due to the different patterns of spatial variation in these soil properties.  相似文献   

两种真姬菇摇瓶发酵产生菌丝体及 胞外多糖研究   总被引：1，自引：0，他引：1  

刘成荣  邓百万 《中国农学通报》2008,24(9):287-292

采用摇瓶培养法对2种真姬菇的发酵工艺进行研究,结果表明：真姬菇Ⅰ、Ⅱ发酵生产菌丝体及胞外多糖的碳源是葡萄糖,氮源是酵母膏;液体发酵培养基是葡萄糖3%、酵母膏 0.4%、vitB1 10mg/100ml、KH₂PO₄ 0.1%、MgSO₄ 0.1%,pH值为6.0;液体发酵的优化条件是初始pH 6.0~7.0,振荡速度110~130r/min,培养温度25~28℃,装液量150ml/250ml。2种真姬菇菌丝体及胞外多糖产量较高,真姬菇Ⅰ菌丝体干重、胞外多糖产量分别是 3.92、8.83 mg /ml;真姬菇ⅠⅠ菌丝体干重、胞外多糖产量分别是3.25、7.69 mg /ml,即真姬菇Ⅰ摇瓶发酵菌丝体干重、胞外多糖产量高于真姬菇Ⅱ。  相似文献   

青钱柳简易育苗技术     

吴运辉  姜芝琼  杨承荣 《种子》2017,(6):128-129

介绍了青钱柳的种子采集、种子处理、种子贮藏及苗木培育的关键技术,是青钱柳常规育苗的主要技术措施.  相似文献   

两步路户外助手APP在生物多样性调查中的应用     

李成容  李云  周材权 《四川林业科技》2021,(1):149-152

生物多样性为人类社会的生存和发展提供了基础的环境和物质条件,而随着生物多样性问题的日益突出,对于生物多样性的研究和保护也有了更高的要求.野外调查作为生物多样性研究和保护的基础工作,提高其调查的准确性以及便利性尤为重要.两步路户外助手是一款能够在手机和平板电脑上使用的专业户外软件,具有离线地图下载及导航、路线设计、轨迹记...  相似文献   

不同施肥水稻土可溶性有机氮组分差异及影响因素   总被引：3，自引：1，他引：3  

杨静  聂三安  杨文浩  陈成榕  张黎明  周碧青  邢世和 《土壤学报》2018,55(4):955-966

可溶性有机氮(Soluble Organic Nitrogen,SON)在研究土壤供氮能力方面至关重要,而目前关于水田生态系统SON组成及其影响因素尚不清楚。运用红外光谱和氨基酸自动分析仪研究了长期(33年)不同施肥处理对水稻土SON含量、组分的影响及其主控因子。结果表明:单施化肥、化肥+牛粪、化肥+稻草处理土壤SON较不施肥处理提高23.49%、58.70%和106.30%,游离氨基酸氮提高32.27%、84.42%和95.21%,可溶性蛋白氮提高20.83%、70.00%和95.83%;不同施肥处理土壤游离氨基酸组成均以中性氨基酸占优势;土壤可溶性氮官能团组成均具有酰胺类化合物的红外特征吸收峰;RDA结果表明,土壤SON含量和组成差异明显,CK和NPK处理主要受土壤容重影响,而NPKM和NPKS则主要受有机质、全氮、微生物量氮、蛋白酶和谷氨酰胺酶影响。因此,SON含量和组分变化与施肥处理密切相关,长期添加有机肥能够显著增加土壤SON及其组分的含量,提高土壤供氮潜力。  相似文献   

Soil soluble organic nitrogen and active microbial characteristics under adjacent coniferous and broadleaf plantation forests   总被引：1，自引：0，他引：1  

Shihe Xing  Chengrong Chen  Biqing Zhou  Hui Zhang  Zhongmin Nang  Zihong Xu 《Journal of Soils and Sediments》2010,10(4):748-757

Purpose  

Soil soluble organic nitrogen (SON) is considered as a sensitive indicator of soil nitrogen (N) status and plays an important role in N cycling in forest ecosystems. Most work on forest soil SON to date has been conducted in temperate areas. The information about soil SON pools and dynamics in tropical and subtropical areas is limited. The aim of this study was to investigate the effects of different forest types on soil SON availability and associated microbial properties.  相似文献   

Linking soil bacterial diversity to ecosystem multifunctionality using backward-elimination boosted trees analysis   总被引：1，自引：0，他引：1  

Ji-Zheng He  Yuan Ge  Zhihong Xu  Chengrong Chen 《Journal of Soils and Sediments》2009,9(6):547-554

Background, aim, and scope  

There is increasing evidence of linkages between biodiversity and ecosystem functions. Recent interests on this topic have expanded from an individual-function perspective to a multifunction perspective. This study aims to explore the soil bacterial diversity–multifunctionality relationship.  相似文献   

Biochar nutrient availability rather than its water holding capacity governs the growth of both C3 and C4 plants     

Yuzhe Wang  Lianwei Zhang  Hong Yang  Guijun Yan  Zhihong Xu  Chengrong Chen  Dongke Zhang 《Journal of Soils and Sediments》2016,16(3):801-810

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Soluble organic nitrogen pools in adjacent native and plantation forests of subtropical Australia     

Joanne Burton  Chengrong Chen  Hossein Ghadiri 《Soil biology & biochemistry》2007,39(11):2723-2734

Soil soluble organic nitrogen (SON) can play an important role in soil nitrogen (N) cycling in forest ecosystems. This study examined the effect of land-use change from a native forest (NF) to a first rotation (1R) and subsequent second rotation (2R) hoop pine (Araucaria cunninghamii) plantation on soil SON pools. The impact of residue management on SON pools was also investigated in the 2R forest, where SON was measured in tree rows (2R-T) and windrows (2R-W). Various extraction techniques were used to measure SON pool size in the 0-10, 10-20 and 20-30 cm layers of soil. The results showed that land-use change had a significant impact on soil SON pools. In the 0-10 cm layer, 3.2-8.7, 14-23, 20-28, 60-160 and 127-340 mg SON kg⁻¹ were extracted by water, 0.5 M K₂SO₄, 2 M KCl, hot water and hot 2 M KCl, respectively. The size of the SON pools and the potential production of SON (PPSON) were generally highest in the NF soil and lowest in the 2R-T soil, and in all forest types decreased with soil depth. The larger SON pools in the NF soil coincided with lower soil, litter and root C:N ratios, suggesting that the difference in the size of SON pools between the NF and 1R soil may be related to differences in the quality of organic matter input under the different forest ecosystems. Differences in the size of SON pools between the 1R soil and the 2R soils and between the 2R-T soil and the 2R-W soil may be related to the quantity of organic matter input and time since disturbance. Significant relationships were found between the SON extracted by 0.5 M K₂SO₄ (SON_ps) and 2 M KCl (SON_KCl), and also among the SON extracted by hot 2 M KCl (SON_hKCl), hot water (SON_hw) and water (SON_w), suggesting that the organic N released by these groups of extracts may be at least partly from similar pools.  相似文献