Progress in Relationship between Anatomical Structures of Vegetative Organs and Drought Resistance in Forage Germplasm Resources

The anatomical structures of roots, stems and leaves are very important indicators to＇evaluate drought resistance. The paper reports the relationship between anatomical structures of vegetative organs and drought resistance in forages.

Localization and Dynamic Change of Saponin in Vegetative Organs of Polygala tenuifolia

Anatomical, histochemical and phytochemical methods were used to investigate the structure, localization and dynamic changes of total saponin and senegenin of vegetative organs in Polygala tenuifolia Willd. Histochemical localization results showed that saponin accumulated mainly in parenchyma cells of vegetative organs. The phytochemical results also showed that the saponin accumulated in the vegetative organs of P. tenuifolia, with higher content in roots and lower content in the aerial parts that included stems and leaves. The saponin content and dry weight of the vegetative organs of P. tenuifolia had dynamic variance at the developmental stages and all reached the highest level in the post-fruit period. Hence, the roots and aerial parts should be gathered in August to make full use of the plant. As the root is the main medicinal organ of P. tenuifolia, the content of total saponin and senegenin of different aged and different parts of the root were determined. The content of total saponin and senegenin exhibited a sustained decreasing trend with increasing root age; therefore, the annual roots had high quality. The content of total saponin and senegenin in different parts of the root showed obvious variation. The content in the ＂skin areas＂ was much higher than that of xylem. The results offer a theoretical basis for determining the appropriate harvesting stage and a reasonable harvest of P. tenuifolia.

SOC storage and potential of grasslands from 2000 to 2012 in central and eastern Inner Mongolia, China

Grassland ecosystem is an important component of the terrestrial carbon cycle system. Clear comprehension of soil organic carbon（SOC） storage and potential of grasslands is very important for the effective management of grassland ecosystems. Grasslands in Inner Mongolia have undergone evident impacts from human activities and natural factors in recent decades. To explore the changes of carbon sequestration capacity of grasslands from 2000 to 2012, we carried out studies on the estimation of SOC storage and potential of grasslands in central and eastern Inner Mongolia, China based on field investigations and MODIS image data. First, we calculated vegetation cover using the dimidiate pixel model based on MODIS-EVI images. Following field investigations of aboveground biomass and plant height, we used a grassland quality evaluation model to get the grassland evaluation index, which is typically used to represent grassland quality. Second, a correlation regression model was established between grassland evaluation index and SOC density. Finally, by this regression model, we calculated the SOC storage and potential of the studied grasslands. Results indicated that SOC storage increased with fluctuations in the study area, and the annual changes varied among different sub-regions. The SOC storage of grasslands in 2012 increased by 0.51×1012 kg C compared to that in 2000. The average carbon sequestration rate was 0.04×1012 kg C/a. The slope of the values of SOC storage showed that SOC storage exhibited an overall increase since 2000, particularly for the grasslands of Hulun Buir city and Xilin Gol League, where the typical grassland type was mainly distributed. Taking the SOC storage under the best grassland quality between 2000 and 2012 as a reference, this study predicted that the SOC potential of grasslands in central and eastern Inner Mongolia in 2012 is 1.38×1012 kg C. This study will contribute to researches on related methods and fundamental database, as well as provide a reference for the protection of grassland ecosystems and the formulation of local policies on sustainable grassland development.

Experimental Study on Key Techniques for Indoor Cultivation of Sprout Vegetables in Families

This paper introduced the advantages of planting sprout vegetables in family rooms,expounded assembly principle of indoor cultivating device and the key techniques for indoor cultivating sprout vegetables in families.In the experiment,we assembled a set of indoor cultivating device for sprout vegetables,and summarized the indoor cultivating techniques of sprout vegetables in families.The indoor planting device was suitable for family members to cultivate sprout vegetables in the living rooms,kitchen,balcony and other corner space by using their spare time.It could not only provide high-quality vegetables for families,but also beautify the indoor environments of family rooms,and increase the oxygen content in rooms.This set of indoor cultivating device and techniques was suitable for planting various sprout vegetables(e.g.radish seedling,water spinach seedling,pea seedling,pine willow seedling,sunflower seedling and various bean seedlings,etc.).This is a set of high-efficient spatial planting technique in families,and also an effective way to increase organic vegetable supply for family.

Upper Yellow River air concentrations of organochlorine pesticides estimated from tree bark, and their relationship with socioeconomic indices

Organochlorine pesticide （OCP） concentrations in tree bark from the upper Yellow River region were determined. Total OCP concentrations ranged from 2.7 to 82 ng/g dw, with a mean of 20 ng/g dw. Concentrations of total （E） DDTs （0.49-37 ng/g dw）, HCHs （0.55-4.5 ng/g dw）, and HCB （0.1-1.0 ng/g dw） were much higher than the other OCPs and accounted for 89% of the YOCP concentrations. p,p＇-DDT was the dominant member of the DDT pesticide group and [5-HCH was the dominant HCH isomer. The p,p＇-DDT/p,p＇-DDE and ct-HCH/y-HCH ratios suggested that there were recent DDT and y-HCH releases. OCP concentrations in the air were estimated from the tree bark, and the estimated median 3ZDDTs, EHCHs, and HCB concentrations in the air were 0.09, 0.14, and 0.024 pg/m3, respectively. The relationship between total OCP concentrations and socioeconomic and natural environment indices were assessed using multiple linear regression analysis, and a regression equation including all these factors was obtained. Population density and tertiary industry were the two dominant factors that appeared to affect OCP concentrations in the upper Yellow River region.