Application of SPME Technique in Organotin Compounds Analysis

Solid phase micro-extraction(SPME) is a new sample pretreatment technique,which developed at the end of 1980s.Because of many its advantages,such as simple and rapid operation,high sensitivity,easy automation,and without using toxic organic solvent,this method has been extensively applied to analyze organic pollutants in environment,food and medicament samples.In this paper,SPME technique and analytical characteristics of organotins were simply introduced,and the application of SPME for organotins analysis in environment samples,such as water,wine,body fluid,sediment and biological samples,were reviewed.According to the recent development of SPME study,it is believed that this technique will be widely used in many fields of chemical analysis.     

Effects of Purification Highly Salty Reuse Water Quality by Three Plants in TEDA Landscape River

The effects of purification highly salty reuse water quality are studied by three plants-scirpus tabemaemontanii Gmel, Typha and Canna indica Linn in Tianjin-Economic and Technology Development Area Landscape River. The resuits show that hydraulic retention time has obviously influence on the effects of purification highly salty reuse water quality. Moreover, removal rates of all kinds of contamination vary with HRT, such as removal rate of COD, TN, NH3 - N, NO3-N, TP, PO4-P is 14.47 % -45.09% 25.50% -71.00% ,39.96% -82.47 %, 27.21% -74.41%, 38.91% -90.01%, 38.55% -92.01% respectively. Both the three plants grow and effects of purification of the highly salty reuse water treatment systems operate very well while concentration of TDS is about 4 500 mg/L in the water; pH of effluent water plants is lower than influent. Removal rates of Phosphorus by Scirpus tabernaemontanii Gmel and Typha are higher than its by Canna indica Linn when the HRT is sameness. The reason that Scirpus tabernaemontanii Gmel and Typha are planted with wetland while Canna indica Linn grows in water, at the same time phosphorus is removed from water because of the function of soil adsorption and so on. The rates of removal contaminations else are invariable by the three plants.     

彩叶植物呈色机理及其在园林造景中的应用

彩叶植物具有丰富的色彩和较长的观赏期,是园林景观中的优良植物材料。本研究从色素、光合特性、环境条件3个方面综述彩叶植物的呈色机理,分析和总结其在园林造景中的应用,以期为园林景观的设计应用提供理论参考。     

Screening of Transgenic Soybean Transformed by Means of Pollen-tube Using Kanamycin

Kanamycin was used to screen T0 seeds of the variety Dongnong 46 transformed by means of pollen-tube method. The results showed that 400 mg·L-1 kanamycin could inhibit growth of non-transgenic plants, and 2 positive plants were gotten combined with Gus dyeing and PCR detection. It is proved that this method is e-conomic and effective in preliminary screening the transgenic plants.     

Stem sap flow of Haloxylon ammodendron at different ages and its response to physical factors in the Minqin oasis-desert transition zone,China

Haloxylon ammodendron, with its tolerance of drought, high temperature, and salt alkali conditions, is one of the main sand-fixing plant species in the oasis-desert transition zone in China. This study used the TDP30(where TDP is the thermal dissipation probe) to measure hourly and daily variations in the stem sap flow velocity of H. ammodendron at three age-classes(10, 15, and 20 years old,which were denoted as H10, H15, and H20, respectively) in the Minqin oasis-desert transition zone,China, f...     

GASEOUS REACTIVE NITROGEN LOSSES FROM ORCHARDS,VEGETABLES AND TEA PLANTATIONS

Nitrogen fertilizer application has accelerated the agricultural soil N cycle while ensuring food security. Gaseous reactive N emissions from orchards,vegetables and tea plantations(OVT) are less understood than those from cereal crops. This paper presents a compilation of data on soil ammonia,nitrous oxide, and nitric oxide emissions from 1454 OVT systems at 184 unique experimental locations worldwide aiming to investigate their emission characteristics, emission factors(EF), and contribution t...     

盐度和氮素对向日葵(Helianthus annuus L.)光合速率和生长状况的影响

Understanding the interactions between salinity and fertilizers is of significant importance for enhancing crop yield and fertilizeruse efficiency. In this study a complete block design experiment was performed in the Hetao Irrigation District of Inner Mongolia,China, to evaluate the effects of interactions between soil salinity and nitrogen(N) application rate on sunflower photosynthesis and growth and to determine the optimum N application rate for sunflower growth in the district. Four levels of soil salinity expressed as electrical conductivity(0.33–0.60, 0.60–1.22, 1.2–2.44, and 2.44–3.95 dS m-1) and three application rates of N fertilization(90, 135,and 180 kg ha-1) were applied to 36 micro-plots. Soil salinity inhibited the photosynthetic rate, stomatal conductance, transpiration rate, plant height, leaf area, and aboveground dry matter of sunflowers. The intercellular CO2 concentration first decreased and then increased with increasing soil salinity in the seedling stage, and the instantaneous leaf water-use efficiency fluctuated with soil salinity. The stomatal and non-stomatal limitations of sunflowers alternated in the seedling stage; however, in the bud, blooming,and mature stages, the stomatal limitation was prevalent when the salinity level was lower than 2.44 dS m-1, whereas the nonstomatal limitation was predominant above the salinity level. The application of N fertilizer alleviated the adverse effects of salinity on sunflower photosynthesis and growth to some extent. During some key growth periods, such as the seedling and bud stages, a moderate N application rate(135 kg ha-1) resulted in the maximum photosynthetic rate and yielded the maximum dry matter. We suggest a moderate N application rate(135 kg ha-1) for the Hetao Irrigation District and other sunflower-growing areas with similar ecological conditions.     

The relationship between soil,climate and forest development in the mid-mountain zone of the Sangong River watershed in the northern Tianshan Mountains,China

The mountainous forests in arid regions, being sensitive to climate change, are one of the key research topics related to the mechanism of interaction between climate and the terrestrial ecosystem. In this study, the spatial distribution of a mid-mountain forest and its environmental factors were investigated by using a combination of remote sensing technology, field survey, climate indices and soil nutrient analysis in the Sangong River watershed of the northern Tianshan Mountains. The forest(Picea schrenkiana) was distributed between 1,510 and 2,720 m asl. Tree height and diameter at breast height(DBH) exhibited a bi-modal pattern with increasing elevation, and rested at 2,450 and 2,250 m asl, respectively. The two maxima of DBH appeared at 2,000 and 2,550 m asl, and the taller trees were observed at 2,100 and 2,600 m asl. For the annual mean temperature, the difference was approximately 5.8°C between the lowest and the highest limits of the forest, and the average decreasing rates per hundred meters were 0.49°C and 0.55°C with increasing altitude between 1,500 and 2,000 m asl and above 2,000 m asl, respectively. The annual precipitation in the forest zone first increased and then decreased with the increase of altitude, and the maximum value was at 2,000 m asl. For per hundred meters, the annual precipitation increased with the rate of 31 mm between 1,500 and 2,000 m asl and decreased by 7.8 mm above 2,000 m asl. The SOM, TN and TP were high between 2,000 and 2,700 m asl and low at the lower and upper forest limits. The minimum Ca CO3 concentration, p H value and EC coincided with the maximum precipitation belt at 2,000 m asl. The SOM, TN and TP were high in the topsoil(0–10 cm) and differed significantly from the values observed in the deep soil layers(10 cm). The soil nutrients exhibited spatial heterogeneity and higher aggregation in the topsoil. In conclusion, soil and climate are closely related to each other, working synergistically to determine the development and spatial distribution of the mid-mountain forest in the study area. The order of the importance of environmental factors to forest development in this study is as follows: soil nutrientsprecipitationelevationtemperature.     

模拟氮沉降对红壤阳离子淋溶的影响研究

以中国科学院红壤生态实验站林草生态试验区阔叶林红壤为对象,通过土壤淋溶试验,模拟研究了不同氮输入量对南方红壤阳离子(Ca2 、Mg2 、K 、Na 、H 和A l3 )淋溶的影响。结果表明,无氮(0mgN/月.柱)、低氮(7.8 mg N/月.柱)、中氮(26 mgN/月.柱)和高氮(52 mg N/月.柱)输入处理下,土壤交换态盐基淋溶总量分别占土壤交换性盐基总量的13.6%,18.4%,27.7%,48.1%。不同的盐基离子对氮输入的反应不同,Ca2 和Mg2 淋溶量随氮输入量的增加而增加,对Na 和K 则无明显影响。土壤交换态离子中随淋洗液输出最多的为Ca2 (无氮、低氮、中氮和高氮输入处理的土壤交换态输出量占土壤交换态的比例分别为22.6%,31.4F.7%,82.5%),其次为Na (其比例分别为16.0%,10.7%,17.6%,26.3%),最少的为Mg2 (其比例分别为5.0%,6.9%,11.1%,16.9%),无土壤交换性K 输出。随氮输入的增加,土壤致酸离子H 和Al3 的淋溶量增加。大气氮沉降的增加,将加速南方红壤的养分淋失和相邻水体的酸化。