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Table of Content

    10 December 2017, Volume 36 Issue 12
    Theory and method of soil moisture diagnosis.
    HOU Yan-lin, LI Jing-ya, MI Chang-hong, HUANG Zhi-ping, LIU Shu-tian, ZHENG Hong-yan, DING Jian, WANG Shuo-jin
    2017, 36(12):  3329-3335. 
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    This paper reviewed the theory and methods of soil moisture diagnosis, and introduced the status quo of soil moisture monitoring, diagnosis and prediction in China. Six independent models were emphatically presented, which included balance diagnostic model, statistical diagnostic model, subtractive statistical diagnostic model, ratio statistical diagnostic model, interval days statistical diagnostic model and movable statistical diagnostic model. Meanwhile, an integrated diagnosis-model by combined application of the six independent models was also introduced. Models were established by the data of 87 monitoring sites in 23 counties in 7 provinces during the period of 2012-2014, and were validated by the data of 2015. The results showed that all the models were simple and the parameters were easy to obtain. Integrated diagnostic model was superior to the 6 independent models. In conclusion, the 6 independent models and the integrated diagnostic model were suitable for the diagnosis and prediction of soil moisture based on precipitation.
    Balance diagnostic model of soil moisture.
    LI Zhao, HUANG Zhi-ping, LIU Shu-tian, HOU Yan-lin, ZHENG Hong-yan, DING Jian, MI Chang-hong, WANG Shuo-jin
    2017, 36(12):  3336-3344. 
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    The advantages and disadvantages of traditional water balance method were discussed. The principle and modeling method of balance diagnostic model of soil moisture based on initial soil water content, time-period precipitation and time-period “evapotranspiration, leakage and runoff” were emphatically introduced. The model was established by the data of 87 monitoring sites in 23 counties in 7 provinces during 2012-2014, and validated by the data of 2015. The results showed that the balance diagnostic model had only about 50% qualification rate in diagnosis and prediction. The main reason for the low qualification rate was the small amount of data based on the subsection prediction of the sum of precipitation and soil water content, which led to an inadequate prerequirement for parameter determination. The balance diagnostic model established as a soil moisture diagnostic model needs to be further studied.
    Statistical diagnostic model of soil moisture.
    HUANG Zhi-ping, WANG Shuo-jin, HOU Yan-lin, LIU Shu-tian, ZHENG Hong-yan, DING Jian, MI Chang-hong, HOU Xian-da
    2017, 36(12):  3345-3351. 
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    The principle and modeling method of statistical diagnostic model were introduced. The model is based on precipitation in different periods, soil initial water content and their interaction. Models were established by the data of 87 monitoring sites in 23 counties of 7 provinces during 2012-2014, and were validated by the data of 2015. The results showed that the statistical diagnostic model had high qualification rates (more than 85%) in diagnosis and prediction. The non-fixed time interval of the adjacent soil moisture monitoring date would lead to the emergence of outliers, which was the main reason affecting the qualification rate of model Prediction. Statistical diagnostic model based on daily time series data can predict daily soil water content. In conclusion, statistical diagnostic model can be used alone as a soil moisture diagnosis model.
    Subtractive statistical diagnostic model of soil moisture.
    LIU Shu-tian, ZHENG Hong-yan, WANG Shuo-jin, HOU Yan-lin, DING Jian, MI Chang-hong, HUANG Zhi-ping, HOU Xian-da
    2017, 36(12):  3352-3358. 
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    So far, the moisture diagnosis and prediction model, due to lack of versatility, is difficult to apply. This paper introduces the subtractive statistical model of the six independent models in the feature column of this issue. The change of soil water content between two times of monitoring is the dependent variable in the subtractive statistical method, and the initial soil water content and the precipitation (including irrigation quantity) are the independent variables. Models were established by the data of 87 monitoring sites in 23 counties from 7 provinces during 2012-2014, and validated by the data of 2015. The results showed that the qualified rate of diagnosis and prediction of the subtractive statistical model was about 90%, indicating that the model was applicable. The main reason responsible for the high qualified rate was that the model followed the law of mass conservation and statistics. The errors of the subtractive statistical method were mainly derived from long-distance data of precipitation and lack of irrigation records. Compared with the traditional models, the subtractive statistic method has the following characteristics: less parameters, easy to obtain parameters, parameters having statistical significance, covering full scope of precipitation, and not affected by underlying surface factors. In conclusion, the subtractive statistical model is scientific and practical for the diagnosis and prediction model of soil moisture, and can be used alone.
    Ratio statistical diagnostic model of soil moisture.
    ZHENG Hong-yan, DING Jian, HOU Xian-da, HOU Yan-lin, MI Chang-hong, HUANG Zhi-ping, LIU Shu-tian, WANG Shuo-jin
    2017, 36(12):  3359-3364. 
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    The principle and modeling method of ratio statistical diagnostic model of soil moisture based on time-period precipitation and initial soil water content were introduced. Models were established by the data of 87 monitoring sites in 23 counties in 7 provinces during 2012-2014, and validated by the data of 2015. The results showed that the ratio statistical diagnostic model had high qualification rate (>80%) in diagnosis and prediction. The main reason for the high qualification rate of diagnosis and prediction was that the model parameters were the results of data mining, not determined by human. Daily time series model can predict daily soil water. The results indicated that the ratio statistical diagnostic model could be used alone as a soil moisture diagnosis model.
     
    The interval days statistical diagnostic model of soil moisture.
    LI Jing-ya, HOU Xian-da, HOU Yan-lin, LIU Shu-tian, ZHENG Hong-yan, MI Chang-hong, HUANG Zhi-ping, DING Jian
    2017, 36(12):  3365-3371. 
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    The principle and modeling method of the interval days statistical diagnostic model of soil moisture were introduced. Models were established by the data of 87 monitoring sites in 23 counties from 7 provinces during the period of 2012-2014, and validated by the data of 2015. The results showed that the accuracy of diagnosis and prediction of the interval days statistical diagnostic model was high, reaching up to 90%. Interval days statistics diagnostic model had a high diagnosis and prediction rate because of the addition of the interval days variable, which effectively solved the problem of unfixed interval. The daily time series model could achieve daily prediction of soil moisture. In conclusion, the interval days statistical diagnostic model can be used alone as a soil moisture diagnosis model.
     
    Mobile statistical diagnostic model of soil moisture.
    DING Jian, MI Chang-hong, HOU Xian-da, HOU Yan-lin, HUANG Zhi-ping, LIU Shu-tian, ZHENG Hong-yan, WANG Shuo-jin
    2017, 36(12):  3372-3380. 
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    The principle and modeling method of movable statistical diagnostic model of soil moisture based on soil initial water content and time period daily average precipitation were introduced. Model was established by the data of 87 monitoring sites in 23 counties in 7 provinces during 2012-2014, and validated by the data of 2015. The movable statistical diagnostic model includes time interval model and daily time series model. The results showed that the qualification rate of the time interval model prediction was about 90%, and the qualification rate of daily time series model prediction was about 70%, indicating that time interval model was better than daily time series model. movable statistical diagnostic model needs to be further improved as a soil moisture diagnostic model. The soil initial water content and precipitation should be segmented separately and then modeled respectively with other models.
     
    Integrated diagnostic model of soil moisture.
    MI Chang-hong, ZHENG Hong-yan, HOU Xian-da, HOU Yan-lin, LIU Shu-tian, HUANG Zhi-ping, DING Jian, WANG Shuo-jin
    2017, 36(12):  3381-3391. 
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    The principle and method of integrated diagnostic model of soil moisture were introduced, which synthesizes balance diagnostic model, statistical diagnostic model, subtractive statistical diagnostic model, ratio statistical diagnostic model, interval days statistics diagnostic model and moving statistics diagnostic model. The model was established by using the data of 87 monitoring sites in 23 counties in 7 provinces during the period of 2012-2014, and was validated by using the data of 2015. The results showed that the integrated model had high qualification rate (>97%) in diagnosis and prediction. The advantages of integrated diagnostic model are embodied as: (1) the parameters of the six independent models are different under different climates, underlying surface and management measures. Therefore, the six independent models are not universal even by sitespecific statistics. (2) In the same prediction, one of the prediction results of the six models always has relatively high accuracy. This result is highly correlated with the sum of the precipitation in different periods and the initial soil water content. After adaptive optimization of the six models, the predicted result is selected according to the sum of water income by the probability.
     
    Verification of integrated diagnostic model of soil moisture based on the monitoring data in Jilin Province.
    MI Chang-hong, WANG Shuo-jin, HOU Xian-da, HOU Yan-lin, LIU Shu-tian, ZHENG Hong-yan, HUANG Zhi-ping, DING Jian
    2017, 36(12):  3392-3398. 
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    Integrated diagnosis model is a new method of soil moisture monitoring, diagnosis and forecast. It includes six independent models and some logical relationships, which is determined based on relationships between the sum of water income and soil water content. The six independent models were based on the quantitative relationship between the monitoring data of soil water content and the precipitation of the nearest weather station to diagnose or forecast the soil water content. In this paper, the application accuracy and adaptability of the integrated diagnosis model in the semiarid and semihumid regions of Northeast China were validated by the data of 6 soil moisture monitoring sites in 4 counties in Jilin Province. The model was established by the data during the period of 2013-2014, and validated by the data of 2015. For a better application of the model, the model parameters of each monitoring point were corrected. The results showed that in the case of monitoring point modeling, the models and parameters under different climates and the surface conditions were different. The model had good adaptability in semi-arid and semi-humid regions in Jilin Province, and the qualification rate was above 88%. The model for low rainfall monitoring sites had higher qualification rate. Integrated diagnosis model of soil moisture in the semi-arid and semi-humid regions of Jilin Province had high application accuracy, which provides a case study for the application of the model in this area.
     
    Verification of integrated diagnostic model of soil moisture based on monitoring data in Inner Mongolia.
    LI Jing-ya, WANG Shuo-jin, HOU Yan-lin, LIU Shu-tian, ZHENG Hong-yan, MI Chang-hong, HUANG Zhi-ping, DING Jian
    2017, 36(12):  3399-3406. 
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    The data of 19 soil moisture monitoring sites in 5 counties in Inner Mongolia were used to verify the adaptability of integrated diagnostic mode of soil moisture in the semi-arid regions in Inner Mongolia. Model was established by the data of 2012-2014, and validated by the data of 2015. The results showed that the model had good adaptability in the semiarid regions of Inner Mongolia, and the qualification rate was over 94%. There was no obvious pattern between the qualification rate of the model’s prediction and latitude and longitude, because all monitoring sites were located in semi-arid areas and rainfall difference was small. In conclusion, integrated diagnostic model can be used in semi-arid areas of Inner Mongolia.
    Verification of integrated diagnostic model of soil moisture based on the monitoring data in Gansu Province.
    MI Chang-hong, HUANG Zhi-ping, LIU Shu-tian, HOU Yan-lin, ZHENG Hong-yan, DING Jian, WANG Shuo-jin, HOU Xian-da
    2017, 36(12):  3407-3413. 
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    Using the data of 13 soil moisture monitoring sites in 2 counties in Gansu Province to verify the adaptability of the integrated diagnostic model of soil moisture in the semi-arid and semihumid regions in Northwest China. The model was established by the data during the period of 2012-2014, and validated by the data of 2015. The results showed that the model had good adaptability in the semi-arid and semi-humid regions of Gansu Province, with a qualification rate of over 80% in the semi-humid regions and over 90% in the semi-arid regions. Different precipitation regions had different model parameters, and higher prediction accuracy of the model was found on less-precipitation monitoring sites. In conclusion, the integrated diagnostic model can be used in semi-arid and semi-humid regions in Northwest China.
    The verification of integrated diagnostic model of soil moisture based on the monitoring data in Shanxi Province.
    ZHENG Hong-yan, DING Jian, WANG Shuo-jin, HOU Yan-lin, MI Chang-hong, HUANG Zhi-ping, LIU Shu-tian, HOU Xian-da
    2017, 36(12):  3414-3420. 
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    The data of 16 soil moisture monitoring sites in two counties in Shanxi Province were applied to verify the adaptability of integrated diagnostic model of soil moisture in semi-humid regions in North China. The model was established by the data of 16 monitoring sites in 2 counties in Shanxi Province during the period of 2012-2014, and was validated by the data of 2015. The results showed that the model had good adaptability in semi-humid regions of Shanxi Province, with the qualification rates being over 90%. There was no obvious pattern between the qualification rate of model prediction and latitude and longitude, because the precipitation in the two monitoring counties was close. In conclusion, the integrated diagnostic model used a large amount of data, and the data range covered the whole crop growing season. It has relative advantages over other models and can be applied to semi-humid areas of North China
    Verification of integrated diagnostic model of soil moisture based on the monitoring data in Hebei Province.
    LIU Shu-tian, ZHENG Hong-yan, HOU Xian-da, HOU Yan-lin, DING Jian, MI Chang-hong, HUANG Zhi-ping, WANG Shuo-jin
    2017, 36(12):  3421-3428. 
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    The data of 14 soil moisture monitoring sites in four counties of Hebei Province were used to verify the adaptability of soil moisture integrated diagnostic model in semi-humid regions in North China. Models were established by the data of the 14 monitoring sites during 2011-2014, and validated by the data of 2015. The results showed that the models had good adaptability in semi-humid regions of Hebei Province, with the qualified rates of verification being 76.92%-100%. The model parameters for different regions with different precipitations were different. The models for the regions with less precipitation had higher qualified rates of prediction. Belonging to the coastal areas, Luannan and Laoting counties of Tangshan City had temporal precipitation distributions different from the other two inland counties and thus lower qualified rates. Integrated diagnostic model can be used in semi-humid areas of North China.
    Verification of integrated diagnostic model of soil moisture based on monitoring data in Henan Province.
    DING Jian, MI Chang-hong, HOU Xian-da, HOU Yan-lin, HUANG Zhi-ping, LIU Shu-tian, ZHENG Hong-yan, WANG Shuo-jin
    2017, 36(12):  3429-3435. 
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    The data of 7 soil moisture monitoring sites in 3 counties in Henan Province were applied to verify the adaptability of integrated diagnostic model of soil moisture in humid regions in Central China. Model was established by the data of 7 monitoring sites in 3 counties in Henan Province during the period of 2012-2014, and validated by the data of 2015. The results showed that the model had good adaptability in semi-humid regions of Henan Province, and the qualification rate was over 80%. In the same climatic region, the seasonal precipitation had a greater impact on the prediction qualification rate of the model, which indicated new research content for improving the prediction qualification rate of model in the future. Integrated diagnostic model can be used in semi-humid areas of Central China.
    Verification of integrated diagnosis model of soil moisture based on monitoring data in Hunan Province.
    HUANG Zhi-ping, HOU Xian-da, WANG Shuo-jin, HOU Yan-lin, LIU Shu-tian, ZHENG Hong-yan, DING Jian, MI Chang-hong
    2017, 36(12):  3436-3442. 
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    This paper used the data of 12 monitoring sites of soil moisture in 4 counties of Hunan Province to verify the adaptability of integrated diagnosis model in humid regions of Central China. Model was established by the data of 12 monitoring sites in 4 counties in Hunan Province during the period of 2012-2014, and validated by the data of 2015. The results showed that the model had good adaptability in humid regions of Hunan Province, and the qualification rate was over 85%. The qualification rate of the model showed a tendency to increase with the decrease of average precipitation over the years.
     
    Evaluation of diagnostic models of soil moisture.
    MI Chang-hong, DING Jian, LIU Shu-tian, HOU Yan-lin, ZHENG Hong-yan, HUANG Zhi-ping, HOU Xian-da, WANG Shuo-jin
    2017, 36(12):  3443-3447. 
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    The purpose of this paper was to evaluate the performance of 6 models so as to provide theoretical, methodological and parametric basis for model optimization. Six independent diagnostic models of soil moisture were evaluated by using 4 indexes including preferred model ratio, verification method index, verification mode index and outlier index. The results showed that the model priority was as follows: subtractive statistical diagnostic model and interval days statistical diagnostic model > movable statistical diagnostic model > ratio statistical diagnostic model > statistical diagnostic model > balance diagnostic model. For model type, the daily time series models performed better than the time interval models. The model with high qualification rate included 4 characteristics, that is, the number of independent variables was not more than 3, the independent variables were relatively independent, the model could deal with the uncertain monitoring days, and the parameters were not artificially determined. The six independent models established by the monitoring points can be used separately and solve the nonuniversal of the model. The daily diagnosis and prediction of soil moisture can be realized for real-time matching with remote sensing information and crop growth information. Prediction accuracy of the subtractive statistical diagnostic model and the interval days statistical diagnostic model were the highest, the former was a statistical model based on the law of mass conservation, and the latter effectively solved the prediction error caused by irregular interval days.
    Application conditions of soil moisture diagnostic models.
    LI Jing-ya, HUANG Zhi-ping, LIU Shu-tian, HOU Yan-lin, ZHENG Hong-yan, MI Chang-hong, DING Jian, WANG Shuo-jin
    2017, 36(12):  3448-3455. 
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    The application conditions of moisture diagnostic models were analyzed. These conditions include climate zoning, distance from monitoring site to meteorological station, soil texture, monitoring time, cropping system, crop type, and model parameters. The results showed that six independent diagnostic models (i.e., balance diagnostic model, statistical diagnostic model, subtractive statistical diagnostic model, ratio statistical diagnostic model, interval days statistical diagnostic model, movable statistical diagnostic model) and integrated diagnostic model had universal adaptability. The external reason of the models’ universal applicability was that these models considered only three independent variables (soil water content, period precipitation, and interval days of two monitoring times of soil moisture); the inherent reason for the general applicability of models was that modeling and determining parameters were based on monitoring sites. The average annual precipitation was one of the major factors affecting the qualified rate of model prediction; the smaller the value was, the higher the qualified rate was. In conclusion, the applications of the six independent diagnostic models and the integrated diagnostic model were not affected by underlying surface factors, and these models included three independent variables.
    Theoretical analysis, comprehensive evaluation and prospect of soil moisture diagnostic models.
    ZHENG Hong-yan, MI Chang-hong, LIU Shu-tian, HOU Yan-lin, HUANG Zhi-ping, DING Jian, WANG Shuo-jin, HOU Xian-da
    2017, 36(12):  3456-3461. 
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    Based on the results of researches in the feature column of this issue, this paper makes theoretical analysis, comprehensive evaluation and prospect of the moisture diagnosis models, aiming to establish more practical moisture diagnosis models. The results are as follows: (1) The precipitation data of 87 moisture monitoring sites could be replaced by the precipitation of their nearest meteorological stations; (2) The diagnostic qualified rates of the 6 independent models and the comprehensive model (two categories: the time interval diagnosis and the daily diagnosis) established by 87 moisture monitoring sites were all above 75%; (3) The integrated model was better than the independent models used alone; (4) All models and parameters were established and determined according to the monitoring sites, without the influence of the underlying surface factors; (5) All models were simple, with three independent variables (initial soil moisture content, precipitation during period of monitoring, and the days between two monitoring dates), and parameters easy to get. The models can be established as long as there is a series of soil moisture monitoring data and corresponding precipitation data (monitoring sites or nearby weather stations).
    Effects of simulated nitrogen deposition on alkane and alkene fluxes from forest floor at Dinghushan.
    ZHANG Li-li, YIN Liang, ZHENG Li-li, HUANG Xing-ran, YI Zhi-gang
    2017, 36(12):  3462-3469. 
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    Alkane and alkene, two major types of volatile organic compounds (VOCs), play critical roles in atmospheric chemistry and have great effect on global carbon cycle. Continuing elevated nitrogen deposition will change forest soil ecological processes, which will then influence VOCs fluxes from the forest floor. Static chambers and preconcentratorGC-MS technique were used to investigate the responses of alkane and alkene fluxes to the simulated nitrogen deposition from the floor of two typical forest ecosystems, namely masson pine forest (PF) and monsoon evergreen broadleaf forest (BF) in Dinghushan. The results showed that for the natural nitrogen deposition, PF floor acted as a sink for alkane and a source for alkene, with the maximum uptake rate of -117.616±73.048 pmol·m-2·s-1 for undcane and the maximum emission rate of 220.301±159.543 pmol·m-2·s-1 for α-pinene. BF floor acted as a source of both alkane and alkene. Simulated nitrogen deposition promoted the emission of alkane, changed the function of PF forest floor from alkane “sink” to “source”, and the effect became more significant with the elevating nitrogen level. On the contrary, the emission of alkene was restrained in PF, or even PF floor changed from alkene “source” to “sink”, and the low level of nitrogen input had a significant influence. Simulated nitrogen deposition changed the BF floor from “source” to “sink” for both alkane and alkene. Additionally, alkane flux differed significantly between the two forests, and the alkene flux differed among compounds in the same forest.
    Niche characteristics of dominant plant populations of Loropetalum subcordatum community in Maolan karst forest, Guizhou.
    YU Xiao-ya, YU Rui, HUANG Juan, CHEN Ju, YUAN Zi-yong, YANG Fang
    2017, 36(12):  3470-3478. 
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    Niche structure is a major foundation for protection of rare and endangered plants. In order to understand the niche structure of Loropetalum subcordatum (Benth.) Oliv., we investigated L. subcordatum communities at Maolan, Libo County, China. Importance value was used as an index of resource state, the niche structure of tree, shrub and herb layers in L. subcordatum communities were calculated using the indices of Levins breadth (Bi), Shannon breadth (Bs) and Pianka overlap. The similarity of niche breadth was analyzed by using Bray-Curtis clustering. The results showed that: (1) The niche breadth of L. subcordatumwas relatively large.The Bi and Bs values were 4.32 and 1.53 in tree layer, 3.95 and 1.49 in shrub layer, and 4.55 and 1.56 in herb layer, respectively, reflecting the strong ability of resource use of L. subcordatum.The Bray-Curtis similarity analysis showed that the niche breadth of Cornus controversa, Mallotus philippensis, Miscanthus floridulusand Murraya exotica was similar to that of L. subcordatum. (2) The value of niche overlap of L. subcordatum with the other species was 0.66-0.97, 0.55-0.99 and 0.51-0.96 in tree layer, shrub layer and herb layer, respectively. Specially, the value of niche overlap of L. subcordatumwith the deciduous species in tree layer, shrub layer and herb layer was 0.75-0.88, 0.82 and 0.51-0.80, respectively. These results indicated that L. subcordatumand deciduous species maybe have a complementary demand for resources. (3) The potential competition with evergreen species (especially in shrub layer) may be one of the most important reasons for the danger of L. subcordatum.
    Hierarchical system and its quantitative attribute of moso bamboo rhizome.
    JIANG Guo-hua, YU Li-hua, LI Zhan-dong, NIU Han-wei, SHI Lei
    2017, 36(12):  3479-3484. 
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    As a clonal plant, Phyllostachys edulis, commonly called moso bamboo, can grow rapidly with a complex belowground branching system. Owing to the lack of effective research method and the strong clonal expansion ability of belowground rhizome system, few researches have been conducted on the horizontally spatial hierarchical system and its relation to the functional attributes of bamboo rhizome. Here, a hierarchical system of bamboo rhizome and its standing culm of P. edulis were presented. Then, the change of both diameter and length of bamboo rhizome with rhizome order, and the correlations between rhizome and its rhizome root and between belowground rhizome and its standing culm, were examined. Both diameter and length of moso bamboo rhizome decreased with the increasing rhizome order; in other words, they increased from the proximal end to the distal end. The relationship between biomass of bamboo rhizome and its corresponding rhizome root was best characterized by a power function. The diameter of belowground bamboo rhizome was significantly correlated to the diameter at breast height of the first four-order standing culms, but not to that of the fifth order. Regression analysis indicated that the first two orders contributed more to the growth of belowground bamboo rhizome than both the third and the fourth orders of standing culms. These results of the present paper suggested that the belowground rhizome system of P. edulis is a highly heterogeneous hierarchical system, and the hierarchical rhizome system proposed here is conducive to carry out a more in depth research into bamboo rhizome hierarchical structure and its functional attributes.
    Effect of apple special fertilizer on soil enzyme activities and functional diversity of microbial community in a non-irrigated apple orchard.
    ZHANG Chao1, ZHOU Xu1, ZHANG Hai1*, GUO Fu-qiang1, YAN Jun-fang2, ZHU Li-yuan1
    2017, 36(12):  3485-3492. 
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    The characteristics of soil microbes are sensitive indicators of soil fertility. Fertilization can influence soil physiochemical and biological properties. The present study investigated the effect of inorganic fertilizer (IF), combination of manure and inorganic fertilizer (MIF) and apple special fertilizer (ASF) at the equal N, P2O5 and K2O amount on soil nutrients, enzyme activities and functional diversity of microbial community based on Biolog technique in a 10-year-old Fuji apple orchard. The results showed that the MIF and ASF treatments significantly increased soil organic matter content by 24.01% and 21.07% compared with IF treatment, respectively, whereas there were not significant differences in soil total nitrogen content among treatments. The contents of soil available nitrogen, available phosphorus and available potassium in IF and ASF treatments were higher than those in MIF treatment. MIF and ASF treatments all significantly increased the activities of soil catalase, urease, invertase and alkaline phosphatase, and higher urease and invertase activities (by 18.97% and 13.69%, respectively) were found under ASF treatment compared to MIF treatment. Average well color developments (AWCD), substrate richness (S), Shannon index (H), and Simpson index (E) of microbial community were the highest in ASF treatment. The carbon sources mainly utilized by soil microorganisms were carbohydrates, polymers, amino acids and carboxylic acids, and ASF treatment significantly increased the utilization of carboxylic acids, polyphenols and amines by soil microbes. Principal Component Analysis (PCA) showed that fertilization could alter the carbon source use characteristics of soil microbial community, and carbohydrates were the determinant carbon sources that had a great impact on the first principal component (PC1). Our results confirmed that different fertilization treatments exerted significant impacts on soil enzyme activities and microbial community function of apple orchard, and the application of ASF was better for the improvement of soil enzyme activities and functional diversity of microbial community.
     
    Soil respiration dynamics in sugarcane cropland under different irrigation modes.
    TAN Juan
    2017, 36(12):  3493-3500. 
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    In order to investigate the effects of different irrigation modes on soil respiration in cropland of sugarcane cultivar Liucheng 05-136, five types of irrigation, including subsurface drip irrigation (SSDI), surface drip irrigation (SDI), pipe irrigation (PI), sprinkler irrigation (SI), and microsprinkler irrigation (MSI), were employed. Field measurements of soil respiration rate and related environmental factors (soil temperature and soil water content) were conducted at five growth phases (tillering; early, peak, and late elongation; and maturity) at the Sugarcane Efficient Watersaving Irrigation Test Base in Chongzuo City of Guangxi from March to December in 2015. Soil respiration rates in different treatments showed similar seasonal variability. Seasonal mean soil respiration rate was lowest in the MSI mode (2.59 μmol·m-2·s-1) and highest in the PI mode (4.50 μmol·m-2·s-1). Soil respiration in the PI mode was 61.59%, 27.61%, 15.97% and 12.33% higher than that in the MSI, SSDI, SDI and SI modes, respectively (P<0.01), which indicated that PI irrigation can enhance sugarcane soil respiration rate. The relationship between soil respiration and soil temperature was well explained by exponential functions. Correlations between respiration and temperature were highly significant (P<0.01) under SSDI, SDI, PI and SI modes, and significant under the MSI mode (P<0.05). While the relationship between soil respiration and soil water content could be described with a quadratic function, the correlation was significant only under the PI mode (P<0.05). In comparison to single-factor equation, two-factor equations better predicted soil respiration rate, with coefficients being highly significant (P<0.01, R2=0.41-0.83). The temperature sensitivity coefficient (Q10) of soil respiration was 1.98-2.50. Pipe irrigation was the most temperature sensitive mode, while the least sensitive was the SI mode. These findings provide reference for more comprehensive evaluation of the ecological and environment effects of sugarcane water-saving irrigation practices, for accurately assessing the carbon source/sink features of sugarcane cropland ecosystems.
    Effects of salt stress on mineral element contents in different parts of Elaeagnus angustifolia seedlings.
    LIU Zheng-xiang, WEI Qi, ZHANG Hua-xin
    2017, 36(12):  3501-3509. 
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    Elaeagnus angustifolia L. has been widely planted in many marginal lands and environmentally harsh conditions in northern China. In order to reveal the physiological mechanisms underlying its eminent salt-tolerance, a hydroponic experiment in greenhouse was conducted to investigate the contents, content ratios and transfer coefficients of 11 mineral elements including Na, Cl, K, Ca, Mg, Fe, Cu, Mn, NO3--N, SO42-S and P in different plant parts (roots, stems, leaves and aboveground shoots) of E. angustifolia seedlings stressed with different NaCl concentrations (0, 100 and 200 mmol·L-1) for 30 days. The results indicated that: (1) The Na and Cl contents in various plant parts (roots, stems, leaves and aboveground) of salt-stressed seedlings were all sharply elevated, while the transfer coefficients were significantly decreased. The Na contents in roots, stems, leaves and aboveground part of the seedlings under 200 mmol·L-1 NaCl increased 16.2, 7.2, 9.6 and 8.7 times, and the Cl contents in the same parts increased 4.8, 2.7, 3.7 and 3.4 times, respectively, compared to the control. The transfer coefficients of Na and Cl in 200 mol·L-1 NaClstressed seedlings decreased to 53.6% and 69.6% of those in control plants, respectively. The roots had higher Na and Cl contents as compared with any other plant parts. In 200 mmol·L-1 NaCltreated seedlings, the Na content in roots was 4.3 and 2.9 times as high as those in stems and leaves, and Cl content in roots was 3.7 and 1.5 times as high as those in stems and leaves, respectively. (2) Compared with the nonsalt treatment, the contents of K, Ca, Mg, Fe, Cu, NO3--N, SO42-S and P in roots, stems, leaves and aboveground part, the ratios of K/Na, Ca/Na and Mg/Na, and the transfer coefficients of Mg, Fe, Cu, SO42-S and P of salt-treated seedlings were decreased or significantly decreased, steeply declined, and increased to different extents, respectively. (3) The transfer coefficients of Ca and Mn were significantly elevated as the salt concentration increased, the transfer coefficients of K and Ca were constantly maintained at high levels with a range of 1.07-1.14 and 1.03-1.42, respectively, and K, Ca and Mn in salt-stressed seedlings were preferentially allocated to leaves. Taken together, our findings strongly indicate that the high salt tolerance of E. angustifolia is primarily implemented by root accumulation and restriction of Na and Cl, and effectively constrained transportation of Na from stems to functional leaves. In addition, salt tolerance of E. angustifolia appears to be related with its strong transfer capacity of K, Ca and Mn.
    Effects of elevated \[CO2\] on photosynthesis and relevant physiological characteristics of pepper (Capsicum annuum L).
    YUAN Rui, NIE Lei-yun, HAO Xing-yu, SUN Sheng, ZONG Yu-zheng, LI Ping
    2017, 36(12):  3510-3516. 
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    Studying the effect of elevated atmospheric CO2 concentration on photosynthesis and relevant physiological characteristics of pepper and revealing the relationship between atmospheric CO2 concentration and photosynthesis and physiological indexes of pepper can provide a theoretical basis for the cultivation and fruit processing of pepper. Changes in morphological parameters, leaf physiological indexes, photosynthesis, photosynthetic pigment content, Vc content, biomass and yield in response to elevated CO2 concentration (control level+200 μmol·mol-1) were determined in pot experiment using an open-top chamber (OTC) experimental facility. The results showed that the elevated CO2 concentration promoted the growth of pepper and increased plant height, yield and total biomass. At elevated CO2 concentration, leaf net photosynthetic rate (Pn), intercellular CO2 concentration (Ci) and water use efficiency (WUE) increased, stomatal conductance (Gs) and transpiration rate (Tr) increased in blossom and fruit period while decreased during fruiting stage. Elevated CO2 concentration also significantly increased Vc content in the leaves and fruits and the contents of chlorophyll and carbohydrate in the leaves of pepper. Elevated CO2 concentration improved the photosynthetic system and increased the photosynthesis of pepper leaves, and then promoted the accumulation of metabolic substances, which are beneficial to the growth and development of pepper.
    Effects of biochemical inhibitor combination and fertilization mode on rice yield and economic benefit in yellow clayey field.
    ZHOU Xuan, WU Liang-huan, DAI Feng
    2017, 36(12):  3517-3525. 
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    Application of urease inhibitor/nitrification inhibitor can effectively control soil nitrogen (N) transformation, reduce N loss, and improve N use efficiency of crops. In this study, an experiment was conducted to investigate the effects of biochemical inhibitors (NBPT/NPPT+CP) combined with fertilization mode (once or three times) and their interactions on rice yield, yield components, and economic benefit in yellow clayey field using two factor randomized block design. The results showed that biochemical inhibitor combination and fertilization mode had significant effects on rice yield and economic benefit (P<0.001), whereas their interaction effect was not significant (P>0.05). Three time urea fertilization treatment (U3) significantly increased grain yield and economic benefit by 14.2% and 14.6% (P<0.05), respectively, compared to once fertilization treatment (U). Compared with U treatment, U+NBPT, U+NPPT, U+CP, U+NBPT+CP, U+NPPT+CP treatments significantly increased rice yield by 22.8%, 22.2%, 20.1%, 24.1% and 25.8% (P<0.05), and economic benefit by 25.2%, 24.6%, 22.2%, 26.2% and 28.1% (P<0.05), respectively. Compared with U3 treatment, U3+NBPT, U3+NPPT, U3+CP, U3+NBPT+CP, U3+NPPT+CP treatments significantly increased rice yield by 10.8%, 13.5%, 12.8%, 12.0% and 15.8% (P<0.05), and economic benefit by 11.7%, 14.7%, 14.0%, 12.6% and 16.8% (P<0.05), respectively. Addition of a newtype urease inhibitor NPPT alone or combined with CP had a yieldincreasing effect similar to that of NBPT. Path analysis showed that the direct effect of once fertilization on rice yield ranked as 1000-grain weight (0.460)>effective panicles (0.436) >grains per panicle (0.385); three-time fertilization ranked as effective panicles (1.040)>grains per panicle (0.304)>1000 grain weight (-0.059). In conclusion, fertilization plus inhibitor application can effectively enhance the grain sink and increase rice production with better income in yellow clayey field, and can further improve the production potential of crop varieties when combined with a suitable fertilization mode.
    Effects of mixture of thidiazuron and ethephon on grain-filling characteristics and hormone regulation mechanism in spring maize.
    LIU Xiao-shuang, GU Wan-rong, PIAO Lin, ZHANG Li-guo, ZHOU Ying, LI Cai-feng, LI Jing, WEI Shi
    2017, 36(12):  3526-3534. 
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    In order to explore the effect of the mixture of thidiazuron and ethephon on grainfilling characteristics and hormone changes in grains during late grain-filling stage of spring maize, two maize hybrids (‘Xianyu 335’ and ‘Xinxin 2’) were treated with thidiazuron and the mixture of thidiazuron and ethephon 25 days after anthesis, with water as control. The result showed that the mixture of thidiazuron and ethephon decreased the duration of rapid increase period and moderate increase period of grain-filling stage, increased the average filling rate and grain weight, significantly improved IAA (indole-3-acetic acid) and GA (gibberellin acid) contents in grains at late grain-filling stage, reduced the contents of ABA (abscisic acid) and CTK (cytokinin). At the same time, the ratios of IAA/ABA and GA/ABA in grain-filling stage were significantly increased, and the ratios of CTK/IAA and CTK/GA were decreased, while the ratios of CTK/ABA and GA/IAA were less affected. After the treatment of thidiazuron and ethephon mixture, the contents of ABA and CTK in grains of spring maize were negatively correlated with the rate of rapid growth of grain filling. Our results indicated that the mixture of thidiazuron and ethephon regulated the grain-filling process of spring maize mainly through influencing IAA, ABA, CTK and GA contents and their proportions in grains, and ultimately advanced maturity and improved the yield of spring maize. This study will provide theoretical and experimental basis for application of the mixture of thidiazuron and ethephon to maize production.
    Effects of continuous cropping duration of sorghum on components of root exudates and contents of allelochemicals.
    LI Guang, BAI Wen-bin, REN Ai-xia
    2017, 36(12):  3535-3544. 
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    A study was carried out to explore the composition of root exudates and the content of allelochemicals of sorghum root system in different continuous cropping durations. The sorghum was planted in buckets with the method of soil cultivation. Root exudates of sorghum in different continuous cropping years were extracted using two types of polar solvents, methylene chloride and ethyl acetate, and quantitatively identified with GC-MS, to clarify the composition and content of sorghum root exudates in different continuous cropping years and their relationship with crop yield, providing reference for the mechanism of continuous cropping obstruction and the sustainable development of sorghum planting. The results showed that the sorghum root exudates extracted by the two types of polar solvent contained alkane, alcohol, ester, benzene, ketone, aldehyde, while methylene chloride extracts contained 21 kinds of common root exudates, and the extracts of ethyl acetate contained 35 different types of root exudates. With increasing continuous cropping duration, the type number and relative content of root exudates increased first, peaked at 4 years of continuous cropping and decreased slightly thereafter, while the difference between the 4 years and 12 years of continuous cropping was insignificant. With increasing continuous cropping years, the relative content of hydrocarbon compounds increased first, peaked at 3 years of continuous cropping and decreased thereafter; the relative content of ester compounds increased gradually, with increasing amplitudes of 3.43%-40.13%. The relative contents of benzene, tone, and aldehyde all decreased first and increased thereafter. The quantitative analysis results of allelochemicals showed that, with increasing continuous cropping duration, the content of n-octadecane increased first and then decreased, and the contents of ethylbenzene and butyl acetate increased continuously. Furthermore, crop yield was not impacted by 2 years of continuous cropping, but the growth of sorghum was restrained notably at 3, 4, 12 years of continuous cropping: the ear length, branch number, thousand kernel weight, yield of single plant and the dry matter of single plant all decreased, among which the yield decreased by 2%-41%. Correlation analysis showed that ethylbenzene and butyl acetate contents negatively correlated with ear length, branch number, thousand kernel weight, yield of single plant, and dry matter of single plant, especially for branch number. In conclusion, the continuous cropping sorghum significantly influenced the types and contents of sorghum root exudates, increased the contents of ethylbenzene and butyl acetate (two types of inhibiting allelochemicals), and hence reduced the yield significantly.
    Distribution characteristics of heavy metals in soil-Polygonum capitatum system at Dushan antimony deposit, Guizhou Province.
    WANG Li, YANG Ai-jiang, DENG Qiu-jing, HU Xia, XUE Hong-qi, CHEN Wei-jie, LI Cong
    2017, 36(12):  3545-3552. 
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    The contents and distribution characteristics of six heavy metals (Sb, As, Cd, Zn, Pb, Mn) were investigated by sampling soil and different parts of Polygonum capitatum from Dushan antimony deposit in Guizhou. The results showed that the contents of Sb, As, Cd, Zn, Pb and Mn in soil samples were 1566.55, 23.98, 1.21, 117.81, 34.27 and 460.98 mg·kg-1, respectively. The contents of Sb, As, Cd and Zn were 699.35, 1.20, 4.88 and 1.18 times higher than the soil background values in Guizhou, respectively. In addition, the correlation between Sb and As in soil was significant (P<0.05), showing a homologous pattern. The evaluation using Nemerow comprehensive index showed that the pollution index of soil heavy metals in this area ranged from 112.75 to 1295.22, with an average of 500.37, indicating the serious pollution. Besides, P. capitatum showed good growth and tolerance in the soils contaminated by antimony mining. The Sb and Mn contents in P. capitatum were in order of root > leaf > stalk > flower and leaf > flower > root > stalk, respectively, but As, Cd, Zn and Pb exhibited no obvious pattern. Although As, Cd, Pb contents in P. capitatum were lower than the maximum limits of heavy metals in natural materials of Traditional Chinese Medicine (ISO 18664), Sb in Polygonum capitatum may be harmful to human health.
    Children blood lead levels in urban and suburban areas of China and its influencing factors.
    HAN Zhi-xuan, BI Xiang-yang, GUO Xiang-yi, LIAO Jian-guo
    2017, 36(12):  3553-3557. 
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    To know the change of blood lead levels (BLLs) of children living in urban and suburban areas and the associated factors, BLLs data of 166 cities of China, lead concentrations in soils of 23 cities and the annual mean PM10 of 25 provincial capital cities were collected in 1997-2010. The results showed the weighted mean of BLLs was 98.56 μg·L-1 on the data of 17 articles before 2000 and 69.61 μg·L-1 on the data of 149 articles during 2001-2010. BLLs rose from 1997 to 2000, but fall down in fluctuation since 2000 when Chinese government banned the use of leaded gasoline. On the whole, BLLs declined over time across different provinces, especially in Beijing and the like. BLLs were positively associated with soil lead concentration and PM10 concentration. Urban soil and atmospheric particulates may be the main exposure of lead for children.
    Fish community structure and its relationship with environmental factors of main stream  of Emin River, Xinjiang.
    LIU Hong, NIU Jian-gong, LIU Chun-chi, ZHANG Tao, MINA Mui-ti, CHEN Han-fei, CAI Lin-gang
    2017, 36(12):  3558-3563. 
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    Based on survey at 4 representative sections in main stream of Emin River in October 2016, fish community structure was analyzed. A total of 3148 fish belonging to 3 orders, 4 families, 10 genera and 11 species were collected. The dominant species in main stream of Emin River were Carassius auratus Linnaeus, Triplophysa strauchiiKessler, Pseudorasbora parva Temminck et Schlegel,Triplophysa stoliczkae Steindachner and Abbottina rivularis Basilewsky. The analysis of fish community diversity showed that diversity indices of section 1 and section 4 were higher than those of other two sections. According to analysis of DCA and RDA, fish community was classified into 3 groups: section 1 and section 2, section 3, section 4. pH and dissolved oxygen (DO) were the major environmental factors affecting the fish community, followed by temperature and conductivity. This study preliminarily revealed the fish community structure characteristic in main stream of Emin River, and provided reference for conservation and utilization of fish resources in the study region.
    Assessment of social value of ecosystem services based on SolVES model and visitor’s preference: A case study of Taibai Mountain National Forest Park.
    GAO Yan, LIU Kang, MA Qiao, LI Ying, FAN Ya-ning, LI Xiu-qing, GU Chao
    2017, 36(12):  3564-3573. 
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    The social value of ecosystem services plays a significant role in natural ecosystems. The traditional ecosystem service values evaluation is mainly based on the economic value evaluation, while the social value assessment is rare. In this paper, we selected Taibai Mountain National Forest Park as the study area and analyzed the spatial heterogeneity of 10 social values based on the Social Value for Ecosystem Services (SolVES), such as aesthetic, biodiversity, life sustaining, spirit, etc. The results showed that: (1) The “hotspots” of Taibai Mountain National Forest Park were concentrated in middle and alpine areas, where the Dayehai and Baxiantai were the most intensive; (2) The higher aesthetic, biodiversity, life sustaining and spiritual values based on the high degree of preference for tourists were primarily distributed in the alpine area, and the relationship between the value index of each social value type and the geo-environmental condition was significantly correlated with the spatial distribution of the higher social value; (3) The results of spatial distribution assessment of social values in terms of male and female tourists were consistent with the overall assessment of social values; however, there were slight differences in the area at an elevation of below 3500 m in the study area. The SolVES model had a good performance in evaluating the social value of mountain forest park ecosystem services, with high reliability and wide application prospect.
     
    Spatial variability of thermal environment in Xi’an under the build-up area expansion.
    ZHU Xin-ming, WANG Xu-hong, ZHOU Yong-fang, WU Wen-heng, LIU Zhuang
    2017, 36(12):  3574-3583. 
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    Exploring the spatial variability of urban thermal environment under the build-up area expansion is of great significance to better understanding of urban heat island (UHI) effect and improvement of urban ecological environment. Taking the built-up area of Xi’an as an example, the linear spectral mixing analysis method was used to extract the built-up area boundary using Landsat images of 2005, 2010 and 2016, and the space-time evolution of urban thermal environment was studied through the inversion of thermal infrared remote sensing image. In the meanwhile, based on the footprint of UHI effect and the information capacity technology derived from multidimensional histogram of image, the influence scope and spatial differentiation characteristics of UHI effect in urbanization were quantitatively investigated. Build-up area had a rapid expansion process, and impervious surface area increased significantly in Xi’an from 2005 to 2016. Urban construction enhanced the intensity and level of UHI effect in the study area along with the continuous expansion of build-up area, high-temperature areas increased and continuously overspread, gradually showing a flaky distribution characteristic. The spatial variability of the footprint of UHI effect in Xi’an was very prominent, and the influence range of UHI effect had progressively become small from 2005 to 2016. The information capacity could reflect the influence of urban expansion on the spatial heterogeneity of urban thermal environment, and the spatial heterogeneity of the urban heat island became more complicated with the increase of heat island intensity in Xi’an built-up area during the period of the study.
    The characteristics of thunderstorms in Guangdong Province and their responses to urban heat island effect.
    ZHANG Yu, ZHU Xue-chao
    2017, 36(12):  3584-3593. 
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    Based on the records of thunderstorms and temperatures in 26 weather stations in Guangdong Province from 1960 to 2013, with the climate trend coefficient analysis, MannKendall mutation test, Morlet wavelet analysis, EOF analysis and the contrasting method between suburban and urban weather stations, we analyzed the climatic characteristics of thunderstorms in Guangdong and the influences of urban heat island effect on thunderstorms in the Pearl River Delta region. Our study showed that there were more days of thunderstorms in the west than in the east, with the average days of thunderstorms being 74.3 d per year, mainly occurring between April and September. The days of thunderstorms decreased by 0.43 d·a-1 after the year 1984, with a faster decrease in the west than in the east of the province and the Pearl River Delta region. The annual average number of days with thunderstorms showed long time period cycles of 9-12 years and 21-22 years, and short cycles of 2-3 years and 4-5 years. There existed three modes of spatial anomalies in the province, i.e., accordant, different between east and west, and different between north and south. The heat island effects in the cities of Guangzhou and Shen-zhen since 1984 had become stronger, showing close relationships with thunderstorm days, and with the climate trend coefficients of 0.4936 and 0.3937 for the two cities, respectively. Thus, the urban heat island effect caused by urbanization may to certain extent have increased the number of thunderstorms in the cities of the Pearl River Delta region.
    Temporal and spatial variations of wind speed in Longdong of Gansu Province in recent 55 years.
    SHI Wei, ZHOU Jun-ju, HU Zi-ying, WEI Wei, CAO Jian-jun, ZHU Guo-feng
    2017, 36(12):  3594-3601. 
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    Based on the monthly average wind speed, maximum wind speed, average temperature data of three meteorological stations (Huanxian, Kongtong, Xifeng) in Longdong of Gansu from 1960 to 2014, the temporal and spatial variation characteristics of the wind speed and its influencing factors in Longdong was analyzed by using correlation analysis, Mann-Kendall mutation test and wavelet analysis methods. The results showed that the annual average wind speed had decreased by -0.09 m·s-1·10a-1 from 1960 to 2014, and had rapidly decreased during the period of 1973 to 1984, while entered a stable period of volatility after 1995 in Longdong. The average wind speed was the maximum in the 1960s, and it was the minimum in the 1980s. The rapid decreases of the daily maximum wind speed and the frequency of wind speed over grade 4 made great contributions to the decreased annual average wind speed. The seasonal average wind speed decreased at all three stations, and such trend was the most significant in spring and winter. The fluctuation of wind speed in spring played a predictable role in the fluctuation of wind speed in the other three seasons. The seasonal wind speed in spring (maximum) and autumn (minimum) played a most significant role in annual average wind speed. The average wind speed all decreased at all three stations, and the decreasing speed was gradually decreased from Huanxian, to Xifeng, and to Kongdong. The annual average wind speed had a first main cycle of 26 years, and it began to mutate in 1973. Huanxian and Kongtong were the earliest and the latest station of mutation respectively. The annual average wind speed was negatively correlated with the annual average temperature. The fastest warming occurred in spring and winter, and the reduction of wind speed in these two seasons was also the maximal among the four seasons.
    Research advances of phytolith and phytolith-occluded-carbon in wetland ecosystems.
    WANG Dan, WANG Ao-bo, LONG Gao-fei, LI Yun, PU Yu-lin, ZHANG Shi-rong, JIA Yong-xia, YE Chun
    2017, 36(12):  3602-3609. 
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    Wetland is rich in native species and unique in ecosystem functions on the Earth surface. Much environmental change information was reserved during wetland evolution, recording environmental changes of the wetland. Meanwhile, wetland has huge carbon reserves, so it is usually regarded as both “carbon source” and “carbon sink” in the terrestrial ecosystems. Phytolith research has been received extensive attention in the field of archaeology, paleoenvironment and global carbon sequestration, because phytolith is a significantly important indicator of climate change and long-term mechanism of terrestrial carbon sequestration. Research of phytolith and phytolith-occluded-carbon (PhytOC) is of great significance in exploring vegetation type change, reconstruction of regional paleoenvironment and “carbon sink” of wetland ecosystem. On the base of literatures on wetland phytolith research, this study summarizes the phytolith application in wetland paleoclimate and paleoenvironment, the morphology, content and distribution characteristics of phytolith in the wetland ecosystem, and the PhytOC content and its important role in global carbon sequestration.
    The progress on removal techniques of antibiotic resistant genes from water environment.
    WANG Yu-tong, ZHAN Si-hui, ZHOU Qi-xing
    2017, 36(12):  3610-3616. 
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    The abuse of antibiotics has led to the emergence of antibiotic resistant genes (ARGs). ARGs are difficult to be eliminated from the environment. Nowadays, ARGs have been constantly detected in water and propagated quickly. The pollution of ARGs is a critical problem, posing a serious risk to both ecosystems and human health. This review summarized some important progresses in the methods of removing ARGs from water environment. The removal of ARGs by different treatment processes such as ultraviolet disinfection, chlorination, advanced oxidation (including Fenton oxidation, photocatalytic oxidation, and O3 oxidation), and constructed wetlands was discussed. The advantages and limitations of the applications of these treatments were pointed out. Problems existing in the technologies and solutions were also analyzed, which provided references for future research.
     
    Deep Ecology and its implications for construction of ecological civilization.
    JIANG Lu, CHEN Xing-peng, LU Cheng-peng, ZHANG Zi-long, XUE Bing
    2017, 36(12):  3617-3622. 
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    As a branch of ecological philosophy appeared in the 20th century, Deep Ecology is a sign of western ecology from the shallow to deep, characterized as a holistic philosophy opposing individualism. In this paper, the developmental track of the Deep Ecology was reviewed from the perspectives consisting of popularity, philosophy and practice. We described the action program of Deep Ecology, analyzed the philosophical system of “ecological wisdom T” and the fostering of deep ecological consciousness. Implications for connecting the deep ecology theory into ecological civilization construction were proposed, offering reference towards promoting China’s ecological civilization.
    Recent progress on the personality of fish.
    ZHANG Qiang, FU Shi-jian, XIA Ji-gang
    2017, 36(12):  3623-3628. 
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    ndividual difference is a widespread phenomenon throughout the animal kingdom. Consistent individual difference in fish behavior under different time and space conditions is known as “personality”, which is generally synonymous with “temperament” and “behavioral syndromes”. The personality reflects an individual’s life history strategy, and is closely related to the population dynamics, genetic variation and differentiated speciation. This paper expounded the definition and connotation of personality, and summarized the research progress of the classic behavioral traits (e.g. boldness, exploration, activity, aggressiveness and sociability) that are used to describe fish personality. The potentially neurobiological, physiological, genetic and ecological mechanisms in formation and maintenance of fish personality were discussed. Finally, the prospect of future theoretical research and application of fish personality was proposed from an ecological perspective.