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Yang X.-J.,Chinese Academy of Forestry | Yang X.-J.,Beijing Research and Development Center for Grass and Environment | Sun Z.-Y.,Chinese Academy of Forestry | Han L.,Chinese Academy of Forestry | And 2 more authors.
Forest Research | Year: 2010

Treated by freezing, 1-year-old dormant branches of four Parthenocissus species were used as test materials to determine the electro-conductivities. According to Logistic equation fitting, the semi-lethal low temperatures were calculated. The result showed that the semi-lethal low temperatures and freezing tolerance of the examined species were ranked as; Parthenocissus quinquefolia (- 16. 63°C) , P. tricuspidata(- 10. 78°C) , P. laetecirens(-10. 29°C), and P. henryana(-7.72°C). By comparing several physiological indexes including water saturation deficit, soluble sugar, soluble protein, MDA, and proline contents, it was found that after cold stressing for a whole winter the soluble sugar and proline contents were well correlated to semi-lethal low temperatures. So both of them could be used as the physiological indexes for cold tolerance identification and selection of cold-resistant variety. Source


Zhang X.-L.,Beijing Research and Development Center for Grass and Environment | Li X.-N.,Beijing Research and Development Center for Grass and Environment | Wu J.-Y.,Beijing Research and Development Center for Grass and Environment | Zheng W.,Beijing Research and Development Center for Grass and Environment | And 3 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2010

In the present paper, the feasibility of determination of total nitrogen (TN) content in different types of soil based on NIS technology was studied. Some surface and subsurface soil samples were collected from Jiangsu, Henan, Shanxi, Hebei and Jilin province in China, on behalf of paddy, calcareous, loess, coastal alluvial and black soil types separately. After being air-dried, milled and screened, the scanned spectra were obtained by near-infrared spectrometer using the sample with diameter below 1 millimeter, meantime the content of TN was measured with the traditional Kelvin method. A model between TN content and spectrum was established and also it was modified through some spectrum pretreatment using the OPUS software. Then a best model was chosen with root mean squares of crosscheck (RMSECV) being the lowest. Finally the stability and application of the model was discussed through quantitative analysis. The results showed that a good model can be separately established in each province using the surface soil from the same area on behalf of the same soil type, whose RMSECV were within 0.01% on average, and the correlation efficient was above 0.85 basically. The model established using the surface soil can be well used for analysis of TN content in other surface and subsurface soil from the same area whose TN was within the range of the model. The root mean squares of prediction (RMSEP) and correlation efficient of the quantitative analysis were at about 0.01% and 0.80 separately. However, maybe affected by soil types, the model established in one area had certain limitations in the application to other areas even as its TN content was within the range of the model. Whenas, choosing some data from each area randomly to form a new sample group can establish a good new integrated model with RMSECV and correlation efficient being 0.010 2% and 0.985 6 respectively and that can be well used to predict TN content in soil from each area. Source


Wang Q.,Beijing Research and Development Center for Grass and Environment | Que X.,Chinese Academy of Forestry | Yao S.,Beijing Research and Development Center for Grass and Environment | Xiao B.,Beijing Research and Development Center for Grass and Environment | Li C.,Beijing Research and Development Center for Grass and Environment
Applied Mechanics and Materials | Year: 2013

Multiple sediment quality parameters, including pH, TN, TP, organic carbon and microbial biomass, were used to evaluate the remediation efficiency of the river restoration project carried out in Chaohe river. The results showed that: during the investigation period, for the pH of sediment, there was not significant difference between the planted treatment and the non-planted control; the mean removal efficiencies of TN and TP were 22.0% and 10.6% in sediment, respectively. The maximum removal efficiencies for the sediment were 36.7% on the on TN and 12.7% on TP, which occurred in July. The result suggested that the restoration of aquatic vegetation could potentially be used for pollution preventability and removal in the river for drinking water resource. © (2013) Trans Tech Publications, Switzerland. Source


Yuan X.-H.,Beijing Research and Development Center for Grass and Environment | Sun N.,Beijing Forestry University | Teng W.-J.,Beijing Research and Development Center for Grass and Environment | Yang X.-J.,Beijing Research and Development Center for Grass and Environment | Wu J.-Y.,Beijing Research and Development Center for Grass and Environment
Journal of Plant Resources and Environment | Year: 2011

Survival and death percentages of seedlings of Stipa bungeana Trin., Eragrostis spectabilis (Pursh) Steud., Pennisetum alopecuroides (L.) Spreng., P. alopecuroides 'Little Bunny', Calamagrostis brachytricha Steud., Arundinella hirta (Thunb.) Tanaka, Achnatherum extremiorientale (Hara) Keng, A. splendens (Trin.) Nevski and Andropogon scoparius Michx. were analyzed by sand culture method under 0 (control), 5, 10, 15, 20 and 30 g · L-1 NaCl stress, and their salt tolerances were assessed according to plant death percentage, NaCl concentrations inducing survival or beginning dead of plant and cluster analysis result of six growth indexes under 5 g · L-1 NaCl stress. On the basis, change of growth indexes of A. splendens with the strongest salt tolerance under NaCl stress was analyzed minutely. The results show that according to plant death percentage, NaCl concentrations inducing survival or beginning dead of plant and cluster analysis result of growth indexes, salt tolerance of the nine grasses tested can be assessed. Although their assessment results are not completely same, but appear similar trend. Combining assessment results based on above three methods, salt tolerance of the nine grasses are classified into four grades: Achnatherum splendens is the strongest; Pennisetum alopecuroides, P. alopecuroides ' Little Bunny', Eragrostis spectabilis and Stipa bungeana are stronger; Andropogon scoparius is middle; Calamagrostis brachytricha, Achnatherum extremiorientale and Arundinella hirta are the weakest. Under NaCl stress, electrical conductivity in cultivating substrate and its leachate for A. splendens increases gradually with rising of NaCl concentration. And response of different growth indexes of A. splendens to NaCl stress is vary, in which, effect of NaCl stress on root length is smaller. With rising of NaCl concentration, height, tiller number, root number, dry weight of stem and leaf, dry weight of root and chlorophyll relative content of A. splendens all decrease gradually, while ratio of root-shoot increases gradually. Under NaCl concentration higher than 10 g · L-1, A. splendens seedling can survive, while maintain growth under NaCl concentration lower than 10 g · L-1. Extremely high and extremely low temperatures and change of electrical conductivity of cultivating substrate have a certain effect on growth and salt tolerance of A. splendens seedling. Source


Yuan X.,Beijing Research and Development Center for Grass and Environment | Yang X.,Beijing Research and Development Center for Grass and Environment | Chen C.,Beijing Research and Development Center for Grass and Environment | Wu J.,Beijing Research and Development Center for Grass and Environment
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

Reference evapotranspiration (ET0) is the basic parameter for the vegetation evapotranspiration calculation, the regional water balance analysis, and the water resources management. The ET0 models have different adaptability for different regions because of the difference in meteorological conditions among regions. Measurement using lysimeter is the classical method for ET0 model evaluation in European and American areas, but is seldom used in China, and no research reported for North China. Assessment of four ET0 models, Penman-Monteith (FAO-56), Hargreaves-Samani, Priestley-Taylor, and Penman-van Bavel were conducted in Beijing using tall fescue (Festuca arundinacea L.) turf evapotranspiration measurement by auto-weighing lysimeter during the growing season (April - October) of 2012. Two lysimeters were established in cold-season grass tall fescue for standard ET0. The weather station (Dynamet, Dynamax Co. Ltd.) was set up in the experiment site to measure and record automatically the meteorological data of air temperature, air relative humidity, solar radiation and wind speed at 2 meter height above ground for the ET0 calculation by the models. The linear regression and the root-mean-square error (RMSE) and the index of agreement (d) were used for assessing the prediction accuracy of the different models. The results indicated that the solar radiation showed a linear relationship (R2=0.95, p=2.72×10-7) with the monthly reference evapotranspiration, indicating that the solar radiation energy was the main force to drive water from the vegetation to the atmosphere in SPAC system. The accuracy of the models declined with the time scale. The models showed different deviations in ET0 calculation because of the different parameters input. The monthly ET0 was underestimated by Priestley-Taylor model but overestimated by Penman-Monteith?Hargreaves-Samani and Penman-van Bavel models. For the daily ET0, Hargreaves-Samani and Penman-van Bavel models had a slight overestimation with the rate of 1.0167 and 1.0526, respectively, but Penman-Monteith and Priestley-Taylor models had an underestimation with the rate of 0.8204 and 0.7593, respectively. For the timely ET0, Priestley-Taylor had the lowest value among the models, while other models resulted in different values under different weather conditions. The overall estimation for the ET0 at the monthly, daily, and hourly scales showed that the Penman-van Bavel equation was the most precise method for calculating reference evapotranspiration, with a RMSE of 0.63 mm/d and a d-index of 0.96 (monthly), a RMSE of 1.43 mm/d and a d-index of 0.89 (daily), a RMSE of 0.087 mm/h and a d-index of 0.87 (hourly). The calculating accuracy of Penman-Monteith model was a little lower than that of Penman-van Bavel with a d-index of 0.73-0.93. Source

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