Management Information System of Power Based on C/S and B/S Mode Combined

After analyzing the feature of C/S and B/S modes, a kind of MIS for power industry, which combined C/S with B/S, is put forward. The C/ S platform is developed with the Powerbuilder 7.0 and SQL Server 7.0, and the B/ S platform is developed with ASP and IIS5.0+ SQL Server7.0. Electric power management information system should be constituted by the seventh statures mold piece, which are the electricity measures to collecting, electricity charges settling accounting system, the safety system et al. In order to meet the demand of data safety of enterprises, the method of passing data between C/S and B/S is introduced.     

论提升福建省现代农业科技推广应用能力

立足当前福建省农业科技推广工作中存在的投入不足、成果转化率低、优质科技品种缺乏、社会化服务体系仍不健全、科技资源布局配置还不尽合理等问题,从加强农业＂五新＂推广工作、明确农业科技发展重点领域、建设福建特色新型农业科技创新体系等方面入手,提出提升福建省现代农业科技推广应用能力的发展路径与保障措施。     

Long-term organic phosphorus mineralization in Spodosols under forests and its relation to carbon and nitrogen mineralization

In forest soils where a large fraction of total phosphorus (P) is in organic forms, soil micro-organisms play a major role in the P cycle and plant availability since they mediate organic P transformations. However, the correct assessment of organic P mineralization is usually a challenging task because mineralized P is rapidly sorbed and most mineralization fluxes are very weak. The objectives of the present work were to quantify in five forest Spodosols at soil depths of 0-15 cm net mineralization of total organic P and the resulting increase in plant available inorganic P and to verify whether net or gross P mineralization could be estimated using the C or N mineralization rates. Net mineralization of total organic P was derived from the net changes in microbial P and gross mineralization of P in dead soil organic matter. We studied very low P-sorbing soils enabling us to use lower extractants to assess the change in total inorganic P as a result of gross mineralization of P in dead soil organic matter. In addition, to enable detection of gross mineralization of P in dead soil organic matter, a long-term incubation (517 days) experiment was carried out. At the beginning of the experiment, total P contents of the soils were very low (19-51 μg g⁻¹) and were essentially present as organic P (17-44 μg g⁻¹, 85-91%) or microbial P (6-14 μg g⁻¹; 24-39%). Conversely, the initial contents of inorganic P were low (2-7 μg g⁻¹; 9-15%). The net changes in the pool size of microbial P during the 517 days of incubation (4-8 μg g⁻¹) and the amounts of P resulting from gross mineralization of dead soil organic matter (0.001-0.018 μg g⁻¹ day⁻¹; 0.4-9.5 μg g⁻¹ for the entire incubation period) were considerable compared to the initial amounts of organic P and also when compared to the initial diffusive iP fraction (<0.3 μg g⁻¹). Diffusive iP corresponds to the phosphate ions that can be transferred from the solid constituents to the soil solution under a gradient of concentration. Net mineralization of organic P induced an important increase in iP in soil solution (0.6-10 μg g⁻¹; 600-5000% increase) and lower increases in diffusive iP fractions (0.3-5 μg g⁻¹; 300-2000% increase), soil solid constituents having an extremely low reactivity relative to iP. Therefore, soil micro-organisms and organic P transformations play a major role in the bioavailability of P in these forest soils. In our study, the dead soil organic matter was defined as a recalcitrant organic fraction. Probably because gross mineralization of P from this recalcitrant organic fraction was mainly driven by the micro-organisms’ needs for energy, the rates of gross mineralization of C, N and P in the recalcitrant organic fraction were similar. Indirect estimation of gross mineralization of P in dead soil organic matter using the gross C mineralization rate seems thus an alternative method for the studied soils. However, additional studies are needed to verify this alternative method in other soils. No relationships were found between microbial P release and microbial C and N releases.     

伊乐藻对污染水体中氮、磷的净化效果及其克藻效应

为了科学评价伊乐藻在水生态修复中的实际应用价值,在模拟条件下初步研究了沉水植物伊乐藻（Elodea nuttallii）对污染水体中氮、磷的净化效果及其克藻效应。结果表明,伊乐藻对总氮、氨态氮、硝态氮和总磷均具有一定的净化效果,并且水体中氮、磷起始浓度越高,其去除效果越明显;不同生物量伊乐藻对河水中其他藻类均具有较强抑制作用,并且随着生物量增加,其克藻效应更加明显。     

Microbial use of organic amendments in saline soils monitored by changes in the C/C ratio

An incubation experiment was carried out to investigate whether salinity at high pH has negative effects on microbial substrate use, i.e. the mineralization of the amendment to CO₂ and inorganic N and the incorporation of amendment C into microbial biomass C. In order to exploit natural differences in the ¹³C/¹²C ratio, substrate from two C₄ plants, i.e. highly decomposed and N-rich sugarcane filter cake and less decomposed N-poor maize leaf straw, were added to two alkaline Pakistani soils differing in salinity, which had previously been cultivated with C₃ plants. In soil 1, the additional CO₂ evolution was equivalent to 65% of the added amount in the maize straw treatment and to 35% in the filter cake treatment. In the more saline soil 2, the respective figures were 56% and 32%. The maize straw amendment led to an identical immobilization of approximately 48 μg N g⁻¹ soil over the 56-day incubation in both soils compared with the control soils. In the filter cake treatment, the amount of inorganic N immobilized was 8.5 μg N g⁻¹ higher in soil 1 than in soil 2 compared with the control soils. In the control treatment, the content of microbial biomass C₃-C in soil 1 was twice that in soil 2 throughout the incubation. This fraction declined by about 30% during the incubation in both soils. The two amendments replaced initially similar absolute amounts of the autochthonous microbial biomass C, i.e. 50% of the original microbial biomass C in soil 1 and almost 90% in soil 2. The highest contents of microbial biomass C₄-C were equivalent to 7% (filter cake) and 11% (maize straw) of the added C. In soil 2, the corresponding values were 14% lower. Increasing salinity had no direct negative effects on microbial substrate use in the present two soils. Consequently, the differences in soil microbial biomass contents are most likely caused indirectly by salinity-induced reduction in plant growth rather than directly by negative effects of salinity on soil microorganisms.     

An experimental study of charcoal degradation in a boreal forest

Degradation rates of pyrogenic carbon (PyC) under natural environmental conditions are largely unknown. Here we present results from a field experiment monitoring the change in mass, C- and N concentrations of a variety of charcoal types in a Norwegian boreal forest over a period of 20 months. The charcoal types represent different feedstock tree species, production temperature regimes, and placements in the forest, i.e. above ground, in the humus layer or in contact with the mineral subsoil. The types of charcoal had different initial C concentrations mainly depending on their production temperature. Nevertheless, all types of charcoal at all placements in the forest showed an initial drop in their C concentrations, which subsequently rose back to reach near initial values in part of the charcoal types. In part of the charcoal types, N concentrations decreased throughout the experiment, exhibiting considerable variation among feedstock species, production temperature regime, and placements in the forest. C/N ratios rose especially in charcoal made from wood of Scots pine (Pinus sylvestris L.), and charcoal that had been stored in contact with the mineral subsoil showed the most rapid mass gain. Our results confirm the important influence of production temperature and feedstock type on the degradation of charcoal, but they also show that microbial activity and environmental conditions play significant roles in charcoal degradation and thus for the fate of pyrogenic carbon under natural conditions.     

大学计算机基础实验系统的开发与应用

大学计算机基础课程的一个最重要的教学目就是让学生掌握计算机基本应用技能,可见上机实践在课程中重要性.我们开发本系统就是以任务驱动式的学习方式让学生学习起来目的明确、效果显现、更有成就感,从而激发对计算机应用知识的兴趣,促进学生自主学习,为今后学习和应用计算机打下良好基础.     

不同氨氮浓度对部分亚硝化过程中N_2O释放的影响

[目的]研究氨氮浓度对部分亚硝化过程中温室气体N2O释放的影响。[方法]利用序批式生物膜反应器(SBBR),采用间歇曝气的方式,分析进水不同氨氮浓度对部分亚硝化过程中N2O产生的影响。[结果]当进水氨氮浓度不同时,部分亚硝化过程中DO、ORP变化趋势大体一致,出水中亚硝氮与氨氮的浓度比都能达到1∶1,而且硝氮始终都维持在较低水平。进水氨氮浓度对部分亚硝化过程中N2O的释放有显著影响,氨氮浓度越高,N2O的释放量越大。其中,当氨氮浓度为400 mg/L时,N2O的释放量高达37 mg左右。[结论]部分亚硝化过程中N2O的释放可能与NH4+、NO2-的浓度有关。     

湘西自治州农业信息化的现状、困难与对策

通过对湖南湘西州农业信息化现状的调查,找出了存在的困难和问题,初步分析与探讨了解决问题的对策。     

昆明市月牙潭公园葫芦岛植物应用与配置研究

通过对昆明市月牙潭公园葫芦岛的植物调查,研究其种类组成和在园林绿化中的应用。结果表明：昆明市月牙潭公园葫芦岛有园林植物87种,隶属于47科,68属;乔木、灌木和地被植物分别有36种、40种和11种,乔灌（含地被）比为1∶1.42;常绿植物63种,落叶植物24种,分别占72%和28%;乡土树种22种,引进种14种,分别占总数的61%和39%。并分析了昆明市月牙潭公园植物配置存在的问题,提出了改进的建议。