生态系统营养离子循环及水化学演化的锶同位素示踪

综述了Ｓｒ同位素示踪生态系统离子循环和水化学演化的基本原理、主要内容和最新进展。着重介绍了Ｓｒ同位素在矿物风化速率研究、流域营养离子来源识别及其循环通量计算、地下水体化学成分演化机制的研究中的示踪应用；最后展望了Ｓｒ同位素在生物地球化学过程示踪上的潜在价值。

观赏类水培植物对盐离子的吸收动力学

建立离子色谱分离电导检测法分析水体中K+、Na^(+)、Ca ^(2+)、Mg ^(2+)4种盐离子的含量变化,进一步分析风信子、水仙花和观音竹3种观赏类水培植物对盐离子的吸收利用率以及动力学拟合方程,建立离子吸收的动态模型,为植物培养提供理论依据。结果表明,观赏类水培植物对地表水中Na^(+)、Ca ^(2+)、Mg ^(2+)的吸收符合幂函数模型。水仙花对Na^(+)、Ca ^(2+)、Mg ^(2+)吸收利用率最好,其次是风信子,最后是观音竹,相关系数R 2≥0.8290,除观音竹吸收Na^(+)的回归方程无显著性差异,其余均达到显著水平。观音竹对K+吸收也符合幂函数模型,统计检验达到显著水平,但风信子和水仙花水体中K+的浓度随时间先下降再逐渐增加,最后与植物体内的K+保持相近的浓度。

利用水生大型植物改善水质研究进展

近年来,水质退化已成为威胁人类健康的重要因素,如何减缓水质退化问题已经成为世界关注的焦点。水生大型植物可以吸收水体的营养矿物离子,以此来阻止水体富营养化;可以通过捕捉颗粒物、减缓水流和沉降悬浮颗粒来间接影响金属的滞留;还能降低风速,这样可以减少沉降物的重悬浮。水生植物的种类对营养素吸收具有特异性。因此,在设计一套水处理设施之前应首先考虑选用何种水生植物。本文将综述具有缓和水质退化功能的大部分的水生植物,并对能减少处理时间和费用的水生植物做一探讨。

Role of Nitrogen and Nutrients in Crop Nutrition

Nutrition is an important factor for the growth and development of plants. Among the main nutritional elements, there are nitrogen （N） and calcium （Ca）. The N comes from two forms of inorganic ions, ammonium （NH4＋） and nitrate （NO3） whose functions in the plant are the increase in leaf area and improving the succulence of many crops, among other essential physiological processes. Both the deficit and excess NO3- have a negative impact on plants increasing susceptibility to insect pests and pathogens, while Ca as divalent ion absorbed Ca2＋ plays an important role in control of physiological disorders and the resistance of plants to diseases to increase the mechanical strength. The N and Ca have a close relationship in the nutritional role of the plant, because the Ca absorption acting nitrates, so that a proper balance affects plants better growth and higher strength.

Utilization of Mill Effluent for Growth, Availability and Uptake of Nutrients by Palm Oil Seedlings

A large amount of palm oil mill effluent is one of the issues faced by palm oil producers in Indonesia. To alleviate the environmental pollution, it is necessary to reduce the problem by using it as a liquid organic fertilizer. A pot experiment to determine the effects of mill effluent on growth of palm oil seedlings （Elaeis guineensis Jacq.）, availability and uptake of macronutrients was conducted in Tandun Plantation Unit, province of Riau, Indonesia. The experiment used a randomized block design, consisting nine combinations of mill effluent doses （3.2, 6.4 and 9.6 L） and recommended fertilizer doses （100%, 75%, 50% NPKMg） in 20 kg soil and one control. The experiment was replicated three times. The results showed that plant height, stem diameter and number of fronds of palm oil seedlings at 26 weeks after planting （WAP） were significantly affected by application of 9.6 L mill effluent with 50%-75% NPKMg, The enhancement of soil organic C （Co,g） content, soil pH and cation exchange capacity due to the application of 9.6 L mill effluent combined with 50% NPKMg caused the availability of soil P and total N （Ntot） increased significantly, while exchangeable K was affected by application of 6.4 L mill effluent combined with 100% NPKMg. All treatments did not affect soil exchangeable Mg. A positive correlation between availability of soil N, P, K and its uptake by palm oil seedlings at 26 WAP were indicated by r = 0.61, 0.63 and 0.57, respectively.

Study on the Sulfur Nutrition of the Sugarcane and Balance of Sulfur in Soil for Sugarcane Planting Areas

Areas of planting sugarcane are located in subtropical and tropical parts of Guangxi. These areas are characterized by high temperature, heavy rainfall and nutrients leaching. It results in strong decomposition of soil mineral and a low cation exchange capacity （CEC）, low organic matter, and low phosphorus （P）, potassium （K） and sulfur （S） in soils. In about 30% of the soils in the planting sugarcane regions the total sulfur and the plant-available sulfur are under 150 mg/kg and 12 mg/kg, respectively. The sulfur nutrition is usually supplied insufficiently for sugarcane growth. The total sulfur of and available sulfur are under the medium level in nearly 50% of the soils in the planting sugarcane regions. Therefore, with the improvement of production of the sugarcane, the sulfur soil nutrition will influence and limit sugarcane yield. After application of sulfur fertilizer, available stem, single stem weight increased 5.77%-9.43% of sugarcane yield than without the treatment. It still can improve the cane sugar and fibre content. And the sugarcane can obtain better economic benefits to use the sulfur phosphorus ammonium; it is 18.2-20.23 with output/input （VCR） to use the sulfur fertilizer. Amount of sugarcane absorption sulfur reaches 44.1-67 kg/ha. The treatment with no sulfur fertilizer annual sulfur nutrient lose will be 23.67 kg/ha because sugarcane yield uptake from the field.

Application of NaHCO_3/ DTPA Extractant-ICP Spectrometry Technique in Soil Test for Availability of Nutrients and Heavy Metals

Soil test for availability of nutrients and heavy metals is extensively served as a means for the evaluations of soil fertility, and environmental effects and phytotoxicity of pollutants in soils, and for the fertilizer recommendation in agricultural and environmental sciences. Therefore, great attention has been paid to the measurement of elemental availability in soil test.

锶同位素在森林生态系统研究中的进展

放射性成因锶同位素(87Sr/86Sr)作为一种有效的示踪工具,对理解陆相生态系统结构有极其重要的作用。而非传统稳定同位素δ88/86Sr可以揭示以前所忽略的阳离子在植被中的迁移过程。本文对锶元素在森林生态系统中的循环过程以及定量计算方法进行了综述,阐明了利用放射性成因锶同位素87Sr/86Sr在低温地表迁移过程中不分馏的特性示踪物质来源以及循环途径,利用非传统稳定锶同位素δ88/86Sr来示踪生态系统中生物分馏过程,以及锶元素在植被中的内循环机理,总结采用锶同位素在环境响应和生态系统演化的应用。指出非传统稳定锶同位素与放射性成因锶同位素联立应用将是其在陆地生态系统研究中的发展方向。

Proteomic study provides new clues for complications of hemodialysis caused by dialysis membrane

The complications of hemodialysis accompanied the hemodialysis and threaten the patients’life.Besides the loss of nutrient substance,such as amino acid and vitamin,we found new clues that the adsorbed proteins on common-used polysulfone-based dialysis membrane might be the reason according to the qualitative proteomic study by ionic liquid assisted sample preparation method.Our results indicated that the adsorbed proteins on the membrane were related with complement activation,blood coagulation,and leukocyte-related biological process.The quantitative proteome further demonstrated some significant changes of signal proteins in the post-dialysis plasma after the hemodialysis,such as beta-2-microglobulin and platelet factor-4,which would further verify these new clues.