PROJECTED EFFECTS OF ENERGY POLICIES ON AGRICULTURAL WATER USE AND IRRIGATION1

ABSTRACT: A national and interregional programming model was used in projecting the impacts of alternative energy policies and prices on agricultural production, land use, and irrigation. The alternatives analyzed include (a) natural gas deregulation, (b) natural gas curtailment, (c) doubled energy prices, and (d) tripled energy prices. These alternatives are compared with a base alternative where prices and conditions are at normal levels. Restraints in the model control availability of water, land, nitrogen fertilizers, and energy. Water production functions were used to adjust water use to conform with projected energy prices and policies. Natural gas curtailment would have the largest effect on nitrogen use on irrigated land. Values or shadow prices for lands that remains in irrigation would increase under all of the alternatives because of reduced supply. Increased energy prices generally would increase use of surface water for irrigation and reduce use of ground water due to higher pumping costs. Reductions of 50 percent or more in ground water use would occur in the South Central and Western regions of the United States. Water supply prices increase under all of the alternatives; with the amount varying by regions and the policy or price situation.     

Modelling future soil chemistry at a highly polluted forest site at Istebna in Southern Poland using the "SAFE" model

The multi-layer dynamic model SAFE was applied to the forested catchment Istebna (Southern Poland), to study recovery from acidification. Environmental pollution in the area has been historically high. The model uses data from an intensive monitoring plot established in 1999 in a spruce stand, which was planted in 1880. Observations showed that the soil was depleted of base cations. The measured base saturation in 1999 was between 5 and 8% in the different soil layers. Model predictions assuming full implementation of the UNECE 1999 Gothenburg Protocol and present day base cation deposition show that the base saturation will slowly increase to 20% by 2100. Despite large emission reductions, Istebna still suffers from the very high loads of acidifying input during the past decades. Soil recovery depends on future emissions especially on base cation deposition. The recovery will be even slower if the base cation deposition decreases further.     

Ammonium removal from waste solutions by precipitation of MgNH4PO4 I. Ammonium removal with use of commercial reagents

The method of ammonium ion removal from industrial waste solutions was investigated and parameters for MgNH₄PO₄ precipitation were determined. A solution laden with NH₄⁺ ions was brought to pH 1–2 by the use of H₃PO₄; MgO was then added and the pH adjusted to 9–10 with the use of NaOH solution. Stirring of the suspension was carried out during a prolonged period of time ( 3 hours), with final filtration or sedimentation. By this method the ammonium ion content in the filtrate may be reduced to concentrations below 1 mg/l. The MgNH₄PO₄·6H₂O sediment produced is considered to be a long-term fertilizer, suitable for agricultural use.     

芳烃联合装置地下管线测漏处理过程的风险分析

运用预先危险性分析法(PHA),对芳烃联合装置地下管线测漏处理过程中存在的风险进行了分析,确定了应采取的安全措施,取得了明显效果.     

中国自然灾害和减灾的对策

2006年5月9日防灾科技学院揭牌暨建校30周年庆典之际,马宗晋院士应邀为我校师生作了题为“中国自然灾害和减灾的对策”的学术报告,受到全校师生的热烈欢迎和一致好评。马宗晋院士是我国著名的地质学家,曾担任中国地震局地质研究所所长（现为中国地震局地质研究所名誉所长）,长期从事地质构造、地震预报、地球动力学方面的研究工作,完成了多项国家级重大研究课题。1972年,他率领地震小组,首创渐进式预报模式,提出长中短临渐近蕴震模式,成为中国预报强震的主要思想和工作程序,该模式的预报思想一直影响至今。其间,对海城、松潘等大地震的预测,乃至对唐山大地震的中期估计和短期预报分析都有重要影响,该模式在国际上被誉为“中国式地震预报”;他还提出了地球动力学的模式构想,建立了三个全球的构造系统,论证了地球变动的韵律性和非对称性,从而提出以壳、幔、核细分层角差运动为基础的地球自转与热、重、流联合的动力模式构想,对全球构造动力模式进行了新的分析与综合,为灾害和矿产研究提供了部分基础;提出了综合减灾系统工程设计。马宗晋院士1995年兼任国务院三部委中国重大自然灾害综合研究组组长;2005年任国家减灾委专家委员会主任。 马宗晋院士的报告以大量的研究数据系统地论述了中国的自然灾害和减灾的对策。我国是一个灾害频发、灾种繁多、灾情严重、经济损失巨大的国家,很好的学习和掌握马宗晋院士报告的观点和精神,对于推进我国的防灾减灾事业和从事防灾减灾教育事业均具有十分重要的意义。 我学报编辑部在认真学习和整理马宗晋院士报告的基础上,决定在学报的“院士专家论谈”专题栏目,陆续刊载以“中国自然灾害和减灾的对策”为题的系列文章,并经马院士同意和审核,马智同志编辑整理。我们认为,这对于全国各地从事防灾减灾事业的部门和工作人员,是十分有帮助的。希望各地从事防灾减灾事业和其他工作的读者能够关注这个栏目。[编者按]     

The effects of elevated CO2 on clonal growth and nutrient content of submerge plant Vallisneria spinulosa

An approximately four months long glasshouse experiment was conducted to examine the effects of elevated carbon dioxide (CO(2)) concentration (1,000 +/- 50 micromol mol(-1)) in the atmosphere on biomass accumulation and allocation pattern, clonal growth and nitrogen (N), phosphorus (P) accumulation by the submerged plant Vallisneria spinulosa Yan. Elevated CO(2) significantly increased V. spinulosa total fresh biomass ( approximately 130%) after 120 days, due to more biomass accumulation in all morphological organs than in those at ambient CO(2) (390 +/- 20 micromol mol(-1)). About 75% of the additional total biomass at elevated CO(2) was accounted for by leaf and rhizome (above ground) biomass and only 25% of it belonged to root and turion (below ground). However, the turions biomass exhibited a greater increase rate than that of organ above ground, which caused reduction in the above/below ground biomass ratio. The clonal growth of V. spinulosa responded positively to elevated CO(2). The number of primary ramets increased up to 1.4-folds at elevated CO(2) and induced a dense growth pattern. For nutrients absorption, concentration of N in leaf and in turion was significantly (p 相似文献   

Polycyclic aromatic hydrocarbons (PAHs) in the aerosol in Beijing, China, measured by aminopropylsilane chemically-bonded stationary-phase column chromatography and HPLC/fluorescence detection

We developed a useful analytical method for the determination of polycyclic aromatic hydrocarbons (PAH) concentrations in the aerosol of China. We used an accelerated solvent extraction (ASE) method for the extraction of PAHs from the aerosol samples, in order to reduce the extraction time and the solvent volume used. The optimum purification method was developed, with aminopropylsilane chemically-bonded stationary-phase column chromatography, in order to remove many co-extractives which cannot be removed by conventional purification methods using silica-gel column chromatography. HPLC/fluorescence detection (FLD) was adopted as the analytical method, because it has very high sensitivity to PAH and it is easy to install, operate, and maintain as compared with GC/MS. With the analytical method developed in this study, the recovery and precision (RSD) for most of the PAHs ranged from 75% to 129% and from 2.8% to 22.7%, respectively. The concentrations of PAHs in the aerosol samples collected from October 2003 to April 2005 in Beijing, China were determined using the newly developed method. SigmaPAHs, which is the sum of the concentrations of all detected PAHs, was 177.8 +/- 239.9 ng m(-3) (n = 64). The SigmaPAHs concentration in the heating season (305.1 +/- 279.0 ng m(-3), n = 33) was 7.2 times higher than that in the non-heating season (42.3 +/- 32.0 ng m(-3), n = 31). These strong seasonal variations in atmospheric PAH concentration are possibly due to coal combustion for residential heating in winter.     

Methods for the preparation of a biodesulfurization biocatalyst using Rhodococcus sp

Several methods to prepare a biodesulfurization (BDS) biocatalyst were investigated in this study using a strain of Rhodococcus sp. 1awq. This bacterium could selectively remove sulfur from dibenzothiophene (DBT) via the "4S" pathway. DBT, dimethylsulfoxide (DMSO), sodium sulphate and mixed sulfur sources were used to study their influence on cell density, desulfurization activity, desulfurization ability, and the cost of biocatalyst production. In contrast to that observed from bacteria cultured in DBT, only partial desulfurization activity of strain 1awq was induced by DBT after cultivation in a medium containing inorganic sulfur as the sole sulfur source. The biocatalyst, prepared from culture with mixed sulfur sources, was found to possess desulfurization activity. With DMSO as the sole sulfur source, the desulfurization activity was shown to be similar to that of bacteria incubated in medium with DBT as the sole sulfur source. The biocatalyst prepared by this method with the least cost could remove sulfur from hydrodesulfurization (HDS)-treated diesel oil efficiently, providing a total desulfurization percent of 78% and suggesting its cost-effective advantage.     

Arsenic chemistry in the rhizosphere of Pteris vittata L. and Nephrolepis exaltata L

This greenhouse experiment evaluated the influence of arsenic uptake by arsenic hyperaccumulator Pteris vittata L. and non-arsenic hyperaccumulator Nephrolepis exaltata L. on arsenic chemistry in bulk and rhizosphere soil. The plants were grown for 8 weeks in a rhizopot with a soil containing 105 mg kg(-1) arsenic. The soil arsenic was fractionated into five fractions with decreasing availability: non-specifically bound (N), specifically bound (S), amorphous hydrous-oxide bound (A), crystalline hydrous-oxide bound (C), and residual (R). P. vittata produced larger plant biomass (7.38 vs. 2.32 mg plant(-1)) and removed more arsenic (2.61 vs. 0.09 mg pot(-1) arsenic) than N. exaltata. Plant growth reduced water-soluble arsenic, and increased soil pH (P. vittata only) in the rhizosphere soil. P. vittata was more efficient than N. exaltata to access arsenic from all fractions (39-64% vs. 5-39% reduction). However, most of the arsenic taken up by both plants was from the A fraction (67-77%) in the rhizosphere soil, the most abundant (61.5%) instead of the most available (N fraction).