Soil Organic N Forms and N Supply as Affected by Fertilization Under Intensive Rice Cropping System

Changes of soil organic nitrogen forms and soil nitrogen supply under continuous rice cropping system were investigated in a long-term fertilization experiment in Jinhua, Zhejiang Province, China. The fertilizer treatments included combination of P-K, N-K, N-P, and N-P-K as well as the control. After six years of continuous double-rice cropping, total soil N and hydrolysable N contents remained stable in plots with N treatments, while the hydrolysable N contents were substantially reduced in those plots without N application. Compared to the unbalanced fertilization treatments, P and K increased the percentage of hydrolysable ammonium N in the total soil N with the balanced application of N, and also maintained higher rice grain yields and nitrogen uptake. Grain yield was positively correlated with total N uptake (r = 0.875**), hydrolysable N (r = 0.608**), hydrolysable ammonium N (r = 0.560**) and the hydrolysable unknown N (r = 0.417**). Total N uptake was positively correlated with hydrolysable N (r = 0.608**), hydrolysable ammonium N (r = 0.440**) and hydrolysable unknown N (r = 0.431**). Soil nutrient depletion and/or unbalanced fertilization to rice crop reduced N content in soil microbial biomass, and therefore increased C/N ratio, suggesting a negative effect on the total microbial biomass in the soil.

Effect of Long-Term Fertilization on Organic Nitrogen Forms in a Calcareous Alluvial Soil on the North China Plain

In order to illustrate the change of nitrogen （N） supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil. Soil total N （TN） and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-lnsoluble N, amino acid N and ammonium N in the soil increased significantly （P 〈 0.05） with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased （P 〈 0.05） hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.

Changes in Phosphorus Fractions and Nitrogen Forms During Composting of Pig Manure with Rice Straw

The study was conducted to reveal P fractions and N forms changing characters during composting of pig manure with rice straw.During composting,the NH 4 ＋-N concentration decreased and reached at a relatively low value（〈400 mg kg-1） in the final compost,while the NO 3--N concentration increased.Total N losses mainly occurred during thermophilic phase due to the high temperature,the high NH 4 ＋-N concentration and the increase of pH value.Labile inorganic P was dominated in the pig manure and initial compost mixture.During composting,the proportion of labile inorganic P of total extracted P decreased,while the proportion of Fe＋Al-bound P,Ca＋Mg-bound P and residual P increased.The evolutions of the proportion of labile inorganic P,Fe＋Al-bound P and Ca＋Mg-bound P were well correlated with the changes of pH value,organic matter and C/N ratio.Therefore,composting could increase the concentration of N and P and decrease the presence of NH 4 ＋-N and labile P fractions which might cause environmental issues following land application.

Study on the Agile Virtual Enterprise′s Organizing Form and Running Environment

In this paper, we begin with the swift changes in the knowledge economy time,analyze the implication of the agility, and consider the agile virtual enterprise as the mainorganizational form for the manufacturing enterprises to realize agility. We classify the agilevirtual enterprises into products alliance style and knowledge alliance style, and compares theirmain features and profit distribution models. As a result, we give four basic structures for thebuilding and running of the agile virtual enterprises.

音乐中的时间箭头--以可区分性以及唯一指向性为锚点重新审视音乐的时间结构

文章由“时间箭头”这一广义的话题驱动,通过参考哲学(认识论)和科学(热力学)作为时间箭头词源意义上的上游,论述了时间箭头的两个具体性质:可区分性以及唯一指向性。文章以这两个性质为锚点,分别展开了对应的音乐命题并应用于具体的案例分析:对于可区分性,文章关注了音乐中的“复现”,从“诞生/重生”这一概念对切入,对巴赫的《圣诞节清唱剧》的定位试作新的解读;对于唯一指向性,文章论述了音乐中高点的后移,提出“AB-AAB左偏向模型”,将音乐的时间结构(例如曲式)看作动态生长过程的产物,并因此埋下一个有机主义(organicism)的伏笔。

Digital Entrepreneurship Ecosystem as a New Form of Organizing： The Case of Zhongguancun

Digital innovation is becoming increasingly important in today＇s economy. Many digital innovations are developed not within organizations, but in innovation-driven entrepreneurial ecosystems, where various entrepreneurship related stakeholders collaborate and cooperate. Despite its significance, studies on digital entrepreneurship ecosystems （DEEs） are limited and the concept is largely undertheorized. This study intends to fill that gap by studying how a DEE organizes. This organizing issue is challenging, because stakeholders of a DEE are self-organizing and are not governed by any formal authority. To answer that question, we adopt forms of organizing as a theoretical lens, which provides structure to examine organizing issues. Through an in-depth case study of Zhongguancun, the Silicon Valley of China, we unveil eight processes around the themes of division of labor and integration of efforts. We further show that the forms of organizing feature a balance of centralized design and de-centralized emergence. This balanced view extends the forms of organizing literature, which takes an either/or perspective. Ecosystem architects and policy makers who intend to build entrepreneurship ecosystems to promote local economies can derive practical implications from our findings.

从分裂到架桥:李约瑟早期思想的演变

李约瑟的早期思想分两个阶段。在第一阶段中,他认为人类有科学、哲学、宗教、历史和美学五种基本经验形式,任何一种都无法单独认识世界,唯有综合所有形式才能接近真实,但并不存在综合五种经验形式的统一世界观。在第二阶段中,他摒弃了不可调和世界观的思想,用伦理和政治联结五种经验形式,并吸收有机论和进化论,构建出一个松散的统一世界观。

Short-term effect of temperature variation on the competition between PAOs and GAOs during acclimation period of an EBPR system

Sequencing batch reactor(SBR)for enhanced biological phosphorus removal(EBPR)processes was used to investigate the impact of the temperature shock on the competition between phosphorus-accumulating organisms(PAOs)and glycogen accumulating organisms(GAOs)in start-up stage.During the 34 days operation,SBR was set with temperature variation(0-5 d,22±1℃;6-13 d,29±1℃;14-34 d,14±1℃).PAOs and GAOs were analyzed by fluorescent in situ hybridization(FISH),and intracellular polyphosphate granules were stained by Neisser-stain.The results showed that the influence of temperature shock on PAOs’abundance was more serious than that on GAOs in the enriching process.Under sudden and substantially temperature variation,from 22±1℃ to 29±1℃ and then to 14±1℃,the domination of PAOs was deteriorated.After temperature shock,PAOs’competitive advantages at low temperature that concluded in other study did not appear in our study.As mesophilic,GAOs(indicated by Alphaproteobacteria and Gammaproteobacteria)were more temperature adaptive and better grew and took the domination at 14±1℃ in the end.In the competition process,organisms of tetrad forming organisms(TFOs)-like shape which were considered as typical GAOs,were observed.With the evidence of poly-P granules containing by Neisser-straining and result of FISH,these organisms of TFOs-like shape were better to be assumed as adaption state or a special self-protecting shape of PAOs.