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    10 December 2012, Volume 31 Issue 12
    Storage and characteristics of coarse woody debris in different aged natural Ledum palustre-Larix gmelinii forests in Daxing’anling Mountains of Northeast China.
    WANG Fei1, ZHANG Qui-liang1**, WANG Bing1, BAO Ye2, GAO Xiao-wei1, LI Da-yong1, YE Dong-mei1
    2012, 31(12):  2981-2989. 
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    By using two kinds of criterions, this paper analyzed the species composition, diameter class structure, and decay class of coarse woody debris (CWD) in different aged Ledum palustre-Larix gmelinii forests in Daxing’anling Mountains of Northeast China, aimed to explore the characteristics and storage of the CWD. The density, volume, and biomass of the CWD derived from the Harmon criterion were 350-659 trees·hm-2, 2.64-38.27 m3·hm-2, and 1.13-8.52 t·hm-2, being 52.07%-92.38%, 17.44%-63.13%, and 16.88%-22.11% higher than those derived from the LTER criterion, respectively. With increasing stand age, the density of the CWD derived from the Harmon criterion exhibited a “U” distribution, and the volume and biomass of the CWD showed a near normal distribution, while the density of the CWD derived from the LTER criterion increased gradually from middle age forest, and the volume and biomass of the CWD decreased. The proportions of the density, volume, and biomass of the CWD at high decay class derived from the two criterions increased gradually with the increase of stand age. The decay classes of the CWD in young and middle aged forests were mainly of grades Ⅰ and Ⅱ, while those in nearmature and mature forests were of grades Ⅱ and Ⅲ. The population was composed of L. gmelinii and Betula platyphylla, and the CWD density, volume, and biomass of L. gmelinii occupied above 76%.
    “Bug island” effect of shrubs in Horqin Sand Land of North China and related formation mechanisms.
    ZHAO Ha-lin1**, LIU Ren-tao2, ZHOU Rui-lian3, ZHAO Xue-yong1, ZHANG Tong-hui1
    2012, 31(12):  2990-2995. 
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    In 2008-2009, an investigation was conducted on the community characteristics of soil macro-fauna within and outside the Caragana microphylla and Salix gordejevii in Horqin Sand Land, aimed to understand whether the shrubs in mobile sand land could gather soil macrofauna. As compared with those outside the shrubs, the group number, individual density, and Shannon diversity of soil macrofauna within the shrubs were increased by 125.0%-175.0%, 52.8%-263.9%, and 34.6%-57.1%, respectively, indicating that shrubs had obvious “bug island” effect in mobile sand land. C. microphylla had a greater “bug island” effect than S. gordejevii. Within and outside the shrubs, there were the same dominant groups and a few common groups of soil macro-fauna. However, many soil macro-faunal groups which couldn’t survive outside the shrubs appeared within the shrubs, and the functional group structure of the macro-fauna had obvious change. The “bug island” effect of the shrubs in mobile sand land mainly came from the microclimate effect and “fertile island” effect of shrubs, which reduced wind speed and detained dust, occluded hot sun, improved soil texture and soil moisture, and increased soil nutrient contents, being the main mechanisms of the shrubs in mobile sand land in gathering soil macro-fauna.
    Photosynthetic characteristics and water use strategies of coastal shelterbelt plant species in Southeast China.
    HUANG Min-shen1, DU Xiao-na1, LIAO Meng-meng1, CHEN Lu-zhen1, LIN Guang-hui1,2**
    2012, 31(12):  2996-3002. 
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    By using LI-6400 portable photosynthesis system, PAM-2100 chlorophyll fluorescence analyzer, and stable isotope technique, this paper studied the leaf photosynthetic and fluorescence properties, water sources, and water use efficiency (WUE) of five main tree species in coastal shelterbelt forests in Fujian Province, aimed to understand the photosynthetic properties and water use strategies of main tree species in coastal shelterbelt forests in Southeast China. The net photosynthetic rate, intercellular carbon dioxide concentration, stomatal conductance, and transpiration rate of four mangrove species (Kandelia obovata, Aegiceras corniculatum, Avicennia marina, and Sonneratia apetala) were all significantly higher than Australian pine (Casuarina equisetifolia), while the carbon assimilation capacity of the introduced species S. apetala was significantly higher than the native mangrove species. All the measured fluorescence parameters including maximum relative electron transport rate (rETRmax), half-saturation light intensity (Ek), and Fv/Fm of S. apetala were significantly greater than those of native mangroves, indicating that the photosynthetic capacity of S. apetala was also greater than that of the native mangrove species. Two exotic species (C. equisetifolia and S. apetala) mainly relied on groundwater for their water sources, while all indigenous mangrove species could utilize groundwater, rainwater, and seawater. The instantaneous WUE of C. equisetifolia was significantly lower than that of the four mangrove species, while the latter four species had less difference in their instantaneous WUE. The long-term WUE of K. obovata and S. apetala had no significant difference, but was significantly higher than that of A. corniculatum, A. marina, and C. equisetifolia, suggesting that K. obovata and S. apetala could better adapt to the high salt environment where water was the limiting factor for plant growth and survival.
    Community structure and soil and water conservation benefits of manmade forests inDianchi  Lake watershed, Yunnan Province of Southwest China.
    HU Chang-xing1,2, PENG Ming-chun1, WANG Chong-yun1**, DU Jian-hai1, LI Bo3, CHEN Zhen-Liang4, FU Qi1
    2012, 31(12):  3003-3010. 
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    A plot investigation was made on the community structure of five main man-made forests (Cupressus duclouxiana, Eucalyptus globules, Acacia dealbara, Pinus armandii, and P. yunnanensis plantations) in the Dianchi Lake watershed of Yunnan Province, Southwest China. A functional evaluation index system of soil and water conservation, which consisted of four factors (vegetation, litter, soil, and landform), was established. Based on the normalization and weighting of 8 selected indices, and using ideal point comprehensive evaluation method, the soil and water conservation benefits of the plantations were evaluated. The importance value (IV) of the dominant species in the five plantations was 89.69 for C. duclouxiana, 74.27 for E. globulus, 96.35 for A. dealbara, 84.93 for P. armandii, and 65.65 for P. yunnanensis. Among the five plantations, the species diversity in different layers of E. globules and P. yunnanensis plantations was shrub layer > herb layer > tree layer, and that in different layers of C. duclouxiana, A. dealbara, and P. armandii plantations was herb layer > shrub layer > tree layer. P. yunnanensis plantation had the highest overall community diversity, followed by P. armandii, E. globules, C. louxiana, and A. dealbara plantation. The soil and water conservation benefits of the plantations were  P. unnanensis > P. armandii  > C. duclouxiana > E. globulus > A. dealbara, which revealed that native tree species had more advantages in soil and water conservation. There existed obvious differences in the species diversity and soil and water conservation benefits between different plantations, and thus, it would be needed to select suitable tree species and their reasonable combinations for the local sites to improve their ecosystem functioning and to control soil and water loss.
    Growth and physiological characteristics of Taxus wallichiana var. mairei seedlings under different site conditions.
    LIU Jian-fu1**, WANG Ming-yuan1, YANG Chen1, FAN Yan-ping2, LIU Chun-dong3, FU Jian-qing3
    2012, 31(12):  3011-3017. 
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    To clarify the relationships between the growth, photosynthesis, and active oxygen metabolism of Taxus wallichiana var. mairei and the environment under different stand conditions, and to approach the habitats suitable for the growth of T. wallichiana var. mairei seedlings, an investigation was made on the growth and physiological characteristics of two-year-old T. wallichiana var. mairei seedlings in three different habitats (Camphor stand, Eucalyptus stand, and open space) in Quanzhou of Fujian Province, East China. As compared with those in open space, the plant height and new shoot length of the seedlings in Eucalyptus and Camphor plantations were significantly improved, suggesting that woodland habitats benefited the growth of the seedlings. The seedlings chlorophyll b and carotenoid contents, stomatal conductance, transpiration rate, and net photosynthetic rate in woodland habitats increased significantly, compared with those in open space. The seedling’s soluble sugar and amino acid contents were higher in woodland habitats than in open space, while the seedling’s protein contents were in adverse. The SOD and CAT activities of the seedlings in woodland habitats decreased, while the POD activities increased. Our study suggested that open space habitat could cause a strong light stress on T. wallichiana var. mairei seedlings while woodland habitats could provide indispensable shade environment for the seedling growth, and thus, it would be suitable for T. wallichiana var. mairei seedlings growing in Eucalyptus and Camphor plantations.
    Seasonal variations of soluble sugars in dominant plant species in Alxa Desert of Northwest China.
    LI Pei-guang1,2, ZHOU Hai-yan1**, CHEN Cui-yun1, ZHAO Xin1, LIU Yang1
    2012, 31(12):  3018-3023. 
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    This paper studied the variation characteristics of the contents of glucose, fructose, sucrose, and total soluble sugar in the leaves of dominant plant species Haloxylon ammodendron, Nitraria tangutorum, Zygophyllum xanthoxylon, Reaumuria songarica, and Salsola passerina in Alxa desert in different growth seasons. The total soluble sugar content in the desert dominant plant species exhibited different seasonal variation patterns, with a “V” curve for H. ammodendron and S. passerine, an “N” curve for N. tangutorum and R. songarica, and a “W” curve for Z. xanthoxylon. The ratio of sucrose to hexose in R. songarica and S. passerine leaves was greater than 1, and had similar seasonal variation pattern. Sucrose occupied the largest proportion of the accumulated soluble sugar in different seasons, followed by fructose, and glucose. This study would be helpful for better understanding the physiological regulation mechanism and adaptation mode of desert plants.
    Community structure and regeneration characteristics of Taxus yunnanensis in northwest Yunnan Province of Southwest China.
    LIU Wan-de, LI Shuai-feng, ZHANG Zhi-jun, SU Jian-rong**
    2012, 31(12):  3024-3031. 
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    Taking the Taxus yunnanensis communities in northwest Yunnan Province as test objects and based on the field investigation data at three sites (Lanping, Xianggelila, and Ninglang counties) of northwest Yunnan, this paper analyzed the species composition, species diversity, stem size class, and regeneration features of the T. yunnanensis communities. The dominant species in the T. yunnanensis communities were Yushania niitakayamensis, Tsuga dumosa, T. yunnanensis, Betula albosinensis, and Fargesia yunnanensis. Xianggelila had the higher species richness of family, genus, and shrubs than the other two counties, but no significant differences were observed in the species richness of trees and lianas and the total species richness among the three counties. Lanping and Xianggelila had the higher species richness and abundance at smaller size classes (DBH < 5 cm), while Ninglang had the highest species richness and abundance at the second diameter class (1 cm ≤ DBH < 5 cm) and height class (5 cm ≤H<10 m). The wild T. yunnanensis population had weak regeneration ability through seedling, but had stronger sprouting ability. The ratio of the stems through sprouting to through seedling was 1.314. The major sprouting types at all of the three sites were stem basal sprouting and stem epicormic sprouting. Ninglang had the highest sprouting stems, but all the three sites had no significant differences in the mean diameter and height of sprouting stems.
    Leaf N and P stoichiometry of Tamarix chinensis L. in Laizhou Bay wetland, Shandong Province of East China.
    RONG Qiang-qiang1,2, LIU Jing-tao2**, XIA Jiang-bao2, LU Zhao-hua1,2, GUO Cai-hong1,2
    2012, 31(12):  3032-3037. 
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    Taking Tamarix chinensis L. in Laizhou Bay wetland as test object, this paper analyzed the seasonal variations of the leaf nitrogen (N) and phosphorus (P) stoichiometry and their correlations with soil salt concentration. The leaf N and P contents and N/P ratio of T. chinensis ranged 18.39-32.86 g·kg-1, 1.02-3.16 g·kg-1, and 8.62-23.66, with a mean value of 25.74 g·kg-1, 1.75 g·kg-1, and 15.86, respectively. The seasonal variations of the leaf N and P contents presented a trend of decreasing first and increasing then, with a shape of “inverted parabola”, while an opposite trend was observed for the leaf N/P ratio. The growth of T. chinesis was limited by N at the beginning of the growth season (May), but by P in the middle and late stages of the growth season (July-October). There was a definite positive correlation between the leaf N content and soil salt concentration (P=0.063), a significant negative correlation between the leaf P content and soil salt concentration (P<0.05), and a very significant positive correlation between the leaf N/P ratio and soil salt concentration (P<0.01).
    Dynamics of soil organic carbon pool in Phyllostachy edulis forest and P. edulis-Cunninghamia lanceolata mixed forest in hilly regions of central Hunan, Southern China.
    QI Liang-hua1, DU Man-yi1, FAN Shao-hui1**, YUE Xiang-hua1, AI Wen-sheng2, MENG Yong2, YANG Ming2
    2012, 31(12):  3038-3043. 
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    Pure moso bamboo (Phyllostachy edulis) forest and P. edulis-Cunninghamia lanceolata mixed forest are the main forest types in the hilly regions of central Hunan Province. In this paper, the vertical distribution and seasonal dynamics of soil total organic carbon and soil active organic carbons including microbial biomass carbon (MBC), hot waterextractable carbon (HWC), watersoluble organic carbon (WSOC), and readily oxidizable carbon (ROC) in the two forest types were examined. Compared with pure P. edulis forest, P. edulis-C. lanceolata mixed forest had higher storage of soil total organic carbon and soil active organic carbons. The storage of soil total organic carbon, MBC, HWC, WSOC, and ROC in P. edulis-C. lanceolata mixed forest was 1.20, 1.74, 1.35, 1.15, and 1.27 times higher than those in pure P. edulis forest, respectively, and primarily distributed in the upper soil layer (0-20 cm). There existed a seasonal difference in the storage of different forms of soil organic carbon. For example, the storage of soil total organic carbon was the highest in January and the lowest in October, that of soil MBC was the highest in July and the lowest in January, soil ROC had the highest storage in October and the lowest storage in April, while the storage of soil WSOC was obviously higher in January than in other months. Compared with pure P. edulis forest, P. edulis-C. lanceolata mixed forest had higher ratios of each form of soil active organic carbon to soil total organic carbon, but had poor stability of soil carbon pool. In the storage of soil total organic carbon, soil ROC had the highest proportion, followed by soil MBC, WSOC, and HWC, being 18.85%-19.93%, 0.34%-0.49%, 0.24%-0.25%, and 0.19%-0.22%, respectively. The soil total organic carbon had positive correlations with all the soil active organic carbon forms, and there existed significant positive correlations between soil ROC and MBC, soil ROC and HWC, soil MBC and HWC, and soil HWC and WSOC.
    Effects of salinity on the growth and photosynthetic characteristics of a coastal wetland plant species Tetragonia tetragonoides (Pall.) Kuntze.
    HE Lin1, WANG Wen-qing1, LIN Guang-hui1,2**
    2012, 31(12):  3044-3049. 
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    In any ecological restoration project in coastal areas, it is crucial to select suitable plant species with high salt tolerance and economic significance. In this study, Tetragonia tetragonoides seedlings were sand-cultured with nutritional solution of different salinities (0, 100, 200, 300, 400, and 600 mmol·L-1), and the seedling growth indices, biomass, and photosynthetic and chlorophyll fluorescence parameters were determined after 7-week growth, aimed to approach the salt tolerance of T. tetragonoides. The suitable salinity for T. tetragonoides growth was 0-400 mol·L-1, with an upper limit of 600 mol·L-1, suggesting that T. tetragonoides was a halophyte with higher salt tolerance. The net photosynthetic rate, stomatal conductance, and transpiration rate of T. tetragonoides leaves decreased significantly with increasing salinity, but the stomatal limiting value showed an opposite trend. High salinity could inhibit the leafnet synthetic rate via affecting the closure rate of PSⅡ reaction center, the proportion of the light absorption of photochemical reaction, and the electron transfer rate, and thus, decrease the growth rate of T. tetragonoides. This study showed that T. tetragonoides was a halophyte with high salt tolerance and edible value, and worthy to be popularized in the ecological restoration of coastal wetland.
    Spatial associations of constructive species in Pinus tabulaeformis-Quercus wutaishanica forest in Lingkong Mountain Nature Reserve, Shanxi Province of China.
    JIAO Wen-jing1, GUO Dong-gang2, ZHANG Jie3, SHANGGUAN Tie-liang1,2**
    2012, 31(12):  3050-3057. 
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    Based on the investigation data from a 4hm2 plot of Pinus tabulaeformis-Quercus wutaishanica forest in Lingkong Mountain Nature Reserve of Shanxi Province, China, and by using O'ring point pattern analysis method, this paper analyzed the spatial pattern and relevance of constructive species in this forest. On horizontal distribution with smaller scale (0-20 m), a positive spatial association was observed within the population of P. tabulaeformis but not Q. wutaishanica. The more detailed comparisons showed a negative relevance between P. tabulaeformis and Q. wutaishanica at upper layer, and between upperlayered P. tabulaeformis and intermediatelylayered Q. wutaishanica. In the horizon of greater scale (>20 m), no horizontal relevance was observed within the populations of each species. There was no correlation between P. tabulaeformis at lower layer and Q. wutaishanica at intermediate layer in the areas with a scale greater than 10 m, although their relevance was insignificantly positive in the scale of 0-10 m. Further comparisons found no horizontal relevance between the intermediatelylayered fractions of the two species, and between the lowerlayered Q. wutaishanica and each layer of P. tabulaeformis. Vertically, both positive and insignificant spatial relevance were observed within the populations of each species. However, in the areas with smaller scale (0-20 m), the negative relevance in vertical distribution pattern was significant between the two species.
    Carbon concentration and carbon storage in different components of natural Quercus wutaishanica forest in Ziwuling of Loess Plateau, Northwest China.
    WANG Juan1, CHEN Yun-ming2,3**, CAO Yang2,3, ZHOU Jian-yun1, HOU Lei1
    2012, 31(12):  3058-3063. 
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    To accurately estimate the carbon storage and carbon density in Loess Plateau is of significance to understand the global carbon sinksource balance. In this study, an investigation was made on the carbon distribution in different components of natural Querus wutaishanica (syn. Q. liaotungensis) forest in Ziwuling of Loess Plateau hinterland, aimed to provide basis for accurately estimate the carbon concentration and carbon storage of forest vegetation in Loess Plateau. In the young and medium age, nearmature, and matured Q. wutaishanica forests, the carbon concentration of stem, bark, branch, leaf, and root was 44.16%-47.01%, 44.09%-45.50%, 43.17%-46.25%, 44.67%-46.36%, and 38.93%-41.10%, respectively. In shrub layer, the carbon concentration of leaf, branch, and root was 46.26%-44.39%, 30.19%-48.95%, and 28.06%-40.13%; in herb layer, the carbon concentration of above and belowground parts was 28.38%-45.27% and 24.53%-46.06%, respectively; and in litter layer, the carbon concentration was 32.10%-32.90%. The carbon storage of tree layer in the young and medium age, nearmature, and matured Q. wutaishanica forests was 32.78, 35.51, and 43.79 t·hm-2, and that of shrub layer, herb layer, and litter layer was 3.31, 1.72 and 0.87 t·hm-2, 0.32, 0.77 and 0.64 t·hm-2, and 6.03, 3.14 and 4.37 t·hm-2, respectively. The total carbon storage of the three age forests was 42.45, 41.41, and 49.67 t·hm-2, respectively. All the results indicated that in the Ziwuling of Loess Plateau hinterland, matured Q. wutaishanica forest had the greatest carbon storage, and in the three age natural Q. wutaishanica forests, the carbon storage was in the order of tree layer > litter layer > shrub layer > herb layer. It was considered that in Ziwuling of Loess Plateau hinterland, the carbon storage of matured forest had the greatest contribution to the carbon storage of natural Q. wutaishanica forest, which should be paid more attention in the estimation of the carbon storage of natural Q. wutaishanica forest ecosystem in the study area in the future.
    Photosynthetic properties of two crust mosses during dehydration.
    CHEN Cui-yun1, 2**, LI Xin-rong1, 2, ZHAO Xin1,2
    2012, 31(12):  3064-3069. 
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    Didymodon vinealis and Bryum argenteum are the two important components of biological soil crusts for sand-ixation at Shapotou region of Northwest China. This paper studied the photosynthetic characteristics of the two mosses during dehydration, and detected the expression of related proteins. Along with the reduction of the mosses water content, the mosses water-oluble protein and chlorophyll contents and the kinetic parameters induced by chlorophyll a fluorescence as well as the photosystem proteins decreased significantly, while the mosses ion leakage and carotenoid contents increased significantly and had positive correlations with the water content. These changes were significantly greater for B. argenteum than for D. vinealis. The results implied that dehydration induced the decrease of the mosses protein contents, the damage of cell membrane, and further, the inactivation of PSII reaction center proteins, resulting in the decline of the mosses photosynthetic capability.
    Effects of brassinolide on the isozyme expressions of aerobic respiration enzymes in cucumber seedling roots under hypoxia stress.
    LU Xiao-min1,2, SUN Jin1, GUO Shi-rong1**, HE Li-zhong1, WANG Li-ping1, YANG Yan-juan1
    2012, 31(12):  3070-3074. 
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    A hydroponic experiment was conducted to study the effects of 24-epibrassinolide (EBR) on the isozyme expressions of aerobic respiration enzymes in cucumber seedling roots under hypoxia stress. Hypoxia stress promoted the isozyme expressions of root isocitrate dehydrogenase (IDH), succinate dehydrogenase (SDH), malate dehydrogenase (MDH), and malic enzyme (ME), and produced several new bands. Applying 10 -3mg·L-1 of EBR under hypoxia stress increased the isozyme expressions of IDH and MDH on day 6 and day 9 by 52.8% and 13.6%, and 39.1% and 11.3%, respectively and the isozyme expressions of ME on day 3 by 11.6%, but decreased the isozyme expressions of SDH on day 6 and day 9 by 42.9% and 36.1%, respectively, as compared with those under hypoxia stress alone. These results indicated that applying EBR under hypoxia stress could regulate the isozyme expressions of IDH, SDH, MDH, and ME in cucumber seedling roots, and thereby, alleviate the damage of hypoxia stress on the seedling roots.
    Disaster risk zoning of continuous rain during florescence of summer maize in Henan Province, Central China.
    CHENG Lin1,2, LIU Rong-hua1,2**
    2012, 31(12):  3075-3079. 
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    Continuous rain during florescence has direct impact on the high and stable yielding of summer maize, while the study of disaster risk zoning can provide basis for the management of disaster risk. By using the daily weather data in the period from heading to spinning stage of summer maize and the yield data of summer maize in Henan Province from 1961 to 2010, this paper statistically calculated the average occurrence frequency and scope of continuous rain during the florescence of summer maize, established the series of disaster risk intensity of continuous rain, and extracted the yield loss rate caused by continuous rain with the method of Lagrange’s interpolation. Finally, the risk zoning index for continuous rain was set up to make zoning of continuous rain during florescence of summer maize in the Province. The results showed that the relatively low risk area of continuous rain during the florescence of summer maize with a risk index below 0.25 was mainly distributed in the most part of north of Yellow River, local part of middle Henan, and east part of Nanyang basin, occupying about 33.3% of the whole Province, whereas the high risk area with a risk index higher than 0.5 was in the north part of north Henan and most part of east Henan and south Huaihe River, occupying about 14.8% of the whole Province.
    Effects of oligochitosan on the leaf physiological indices of Brassica napus L. under drought stress.
    LI Yan1, ZENG Xiu-e4, LI Hong-yan1, MA Qing-wen3, ZHAO Xiao-ming2, DU Yu-guang2, WANG Qing5**
    2012, 31(12):  3080-3085. 
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    Taking Brassica napus L., an oil crop broadly cultivated in the world as test object, a greenhouse experiment was conducted to study the effects of oligochitosan on the leaf super oxide dismutase (SOD) and peroxidase (POD) activities, proline content, chlorophyll fluorescence parameters, and relative water content under drought stress. After spraying oligochitosan, the leaf SOD and POD activities decreased at early stage but increased obviously at late stage, whereas the leaf proline content increased obviously throughout the process. The maximum quantum yield of photosystem II (Fv/Fm), excitation capture efficiency of open centers (Fv′/Fm′), photochemical quenching coefficient (qP), and effective quantum yield of photosystem II photochemistry (ΦPSII) all increased obviously, while the minimal fluorescence of darkadapted state (Fo) and nonphotochemical quenching coefficient (qN) had an obvious decrease. The leaf relative water content also increased. It was suggested that oligochitosan could improve the related physiological indices of B. napus against drought, and further, enhance the drought resistance of the oil crop.
    Structure, function, and efficiency of agro-ecosystem around Dongting Lake region of Hunan Province, South-central China based on emergy analysis.
    ZHU Yu-lin1,2**, LIN Ming-jie1, LONG Yu-zi1,2, WANG Mao-xi1, HOU Mao-zhang1, LI Xiao-min1
    2012, 31(12):  3086-3093. 
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    In order to explore the eco-efficiency of agro-ecosystem around the Dongting Lake region of Hunan Province, and to reveal the interrelationships among the human, natural resources, and environment in the ecosystem, this paper analyzed the emergy structure, function, and efficiency of the agro-ecosystem, based on the emergy input-output data in 2009 and by using the emergy method of HT Odum. In the study period, this system was comparatively well developed in economy, and had a higher degree of mechanization and modernization. The fertilizer emergy and agricultural mechanical emergy accounted for 47.13% and 10.62% of the total, respectively, and the emergy density was 8.77×1011sej·hm-2·a-1. The system emergy output was unbalanced, planting emergy output was dominant, while forestry and fishery emergy output was comparatively low. The monetary value of per capita emergy output was 31873.56 yuan, far greater than the per capita gross output value of regional economy in this system (24761.14 yuan), which indicated that the product pricing (especially the planting product pricing) of this system was evidently on the low side, and the value of natural resources and environment was not well reflected by the market. The environmental loading ratio was 1.74, sustainable development index was 1.40, and population bearing capacity was 4.91×105 (the agricultural population in this region was 3.15×106), showing that the system was full of vitality and development potential, the pressure from natural resources and environment was not so high, but the system was under too much employment pressure and the population bearing capacity was overloading. In sum, to further reduce the price scissors between industrial and agricultural products, to keep on protecting the market price of planting products, to adjust the agriculture industrial structure and product structure, and to transfer the surplus labor force would be the essential orientation of agriculture policy in this region.
    Effects of nitrogen fertilization rate and transplanting density on the dry matter accumulation and grain yield of double season rice.
    LIU Wen-xiang1, QING Xian-guo2**, AI Zhi-yong3
    2012, 31(12):  3094-3101. 
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    Taking early rice variety Luliangyou 996 and late rice variety Y-liangyou 86 as test materials, a field experiment with 4 nitrogen (N) fertilization rates and 3 transplanting densities was conducted to study the effects of N fertilization rate and transplanting density on the plant dry matter accumulation, canopy solar energy interception rate, grain yield and its components of double season super hybrid rice. A single peak curve relationship was observed between the N fertilization rate and grain yield of test varieties. A medium N fertilization rate could obtain the maximum yield, with 10245.04 kg·hm-2 for Luliangyou 996 and 11015.37 kg·hm-2 for Y-liangyou 86. The effective panicles increased with increasing N fertilization rate, but the filled grain number per panicle
    reached the peak at medium N fertilization rate (N135 for Luliangyou 996 and N180 for Y-liangyou 86), with the grain·panicle-1 being 143.92 and 142.80, respectively. Transplanting density had minor effects on the grain yields of both Luliangyou 996 and Y-liangyou 86 and the yield components of Luliangyou 996, but had significant effects on the effective panicles and seed setting rate of Y-liangyou 86. High transplanting density induced high effective panicles but low seed setting rate, while low transplanting density was in adverse. The interaction of N fertilization rate and transplanting density had no significant effects on the grain yields of Luliangyou 996 and Y-liangyou 86, but, in terms of high yielding and high fertilizer N use efficiency, the optimal N fertilization rate for Luliangyou 996 and Y-liangyou 86 was 135 and 180 kg·hm-2, and the optimal transplanting density for Luliangyou 996 and Y-liangyou 86 was 45×104 and 30×104 clusters·hm-2, respectively.
    Effects of salt stress on the seedling’s photosynthetic characteristics of different genotypes sweet potato.
    QI Bing-jie1,2, WANG Ji-dong2, MA Hong-bo2, CHEN Jie2, ZHANG Yong-chun2, XU Yang-chun1**, CHANG Zhi-zhou2,3
    2012, 31(12):  3102-3108. 
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    Taking the seedlings of 12 genotypes sweet potato as test materials, this paper studied their photosynthetic characteristics and plant growth under salt stress (0 and 85 mmol·L-1 of NaCl) for 20 days. As compared with the control, 85 mmol·L-1 of NaCl inhibited the growth of the seedlings. Of all the 12 genotypes, the “Zhezi No. 1”, “Xushu No. 18”, and “Xushu No. 22” were lesser impacted, while the “Yanshu 25” and “Langshu 7.12” were damaged more seriously. Under salt treatment, the leaf relative water content (RWC) of different genotypes sweet potato was above 75%, and no significant differences were found among the genotypes. The leaf chlorophyll content index (CCI), net photosynthetic rate (Pn), stomatal conductance (Gs), and instantaneous wateruse efficiency (iWUE) decreased under the treatment of salt. The “Zhezi No. 1” and “Xushu No. 18” had the highest values of CCI and Pn, but the Gs of “Zhezi No. 1” was greatly impacted by salt, with the salinity susceptibility index (SSI) being 22%. The “Yanshu No. 25” was sensitive to NaCl, and had lower SSI of CCI, Pn, and iWUE than the other genotypes. The main reason for the reduction in the photosynthetic rate of “Xushu No. 18”, “Chuan No. 211”, and “Zhezi No. 1” was stomatal limitation, but the three genotypes showed higher photosynthetic efficiency under salt stress. The other nine genotypes were of nonstomatal limitation, but their salt susceptibility differed. In terms of physiological and biochemical indices, the “Zhezi No. 1” and “Xushu No. 18” showed more tolerance against NaCl stress.
    Roles of Eisenia foetida in decomposing different kinds pig dung and crop straw.
    DONG Wei-hua1**, YIN Xiu-qin2, XIN Shu-quan3
    2012, 31(12):  3109-3115. 
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    Fermented foodstuff and feedstuffderived pig dung, rice and maize straw, and their 1:1 and 3:1 mixtures were added with Eisenia foetida, and the physical and chemical properties of the pig dung, straw, and their mixtures were analyzed at the commencement and after 90 days of E. foetida addition, taking no E. foetida addition as the control. After 90 days E. foetida addition, all the test materials appeared mass loss, and the loss rate was significantly greater than that of the control (P<0.01). Under E. foetida addition, the decomposed amount of pig dung-crop straw mixture was significantly higher than that of pig dung or crop straw alone (P<0.01), the mass loss of pig dungmaize straw mixture was significantly greater than that of pig dungrice straw mixture (P<0.05), the 3:1 feedstuffderived pig dungcrop straw mixture had a significantly greater mass loss than the 1:1 feedstuffderived pig dungcrop straw mixture (P<0.01), while the 1:1 and 3:1 mixtures of foodstuffderived pig dung and crop straw had less difference in their mass loss (P>0.05). E. foetida addition increased the total and available N, total and available P, and total and available K contents of test materials, but decreased the materials organic matter content and pH value. The 1:1 foodstuffderived pig dungcrop straw mixture had the largest variation range of organic matter and available N, P, and K contents, suggesting that E. foetida played the greatest role in the decomposition of this mixture. This study would provide theoretical basis for the resource utilization of pig dung and crop straw.
    Effects of water temperature on oxygen consumption rate, asphyxiant point, blood glucose content, and muscle and liver glycogen content of juvenile Coilia nasus.
    XU Gang-chun1, NIE Zhi-juan1, BO Qi-kang2, XU Pao1, GU Ruo-bo1**
    2012, 31(12):  3116-3120. 
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    In order to supply reference for the rational breeding and transportation of Coilia nasus, a laboratory experiment was conducted to measure the oxygen consumption rate (OCR) and asphyxiation point (AP) of juvenile C. nasus under different water temperature, and to study the diurnal variations of the OCR as well as the effects of water temperature on the blood glucose and muscle and liver glycogen of the juveniles. At water temperature (T, ℃) 16-28 ℃, the OCR (R, mg·L-1) of the juveniles increased with increasing temperature, and there was a linear relationship between the R and T (R=0.988T2-32.36T+343.7, R2=0.96). The OCR revealed a diurnal rhythm, with the peak at 7:00 am and the bottom at 9:00 pm. The AP (A, mg·L-1) was significantly correlated to T (A=0.9397T0.8001, R2=0.98). At water temperature 16-24 ℃, the blood glucose content of the juveniles kept relatively steady and ranged from 17.24 to 19.79 mmol·L-1,  while the muscle and liver glycogen content fluctuated. At water temperature 24-28 ℃, the blood glucose content increased significantly with increasing temperature, while the muscle and liver glycogen content had a significant decrease.
    Grasshopper (Orthoptera: Acrididae) density on natural grasslands in upper reaches of Heihe River, Northwest China in relation with topography: An analysis with generalized additive models (GAM).
    LI Li-li, ZHAO Cheng-zhang**, YIN Cui-qin, WANG Da-wei, ZHANG Jun-xia
    2012, 31(12):  3121-3126. 
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    The environmental heterogeneity caused by topographical diversity is an important mechanism of the formation and maintenance of bio-geographic spatial distribution pattern at micro-scale, and also, the prerequisite for the difference in the distribution of species richness. With the help of GIS and S-Plus, the GAM model was used to study the topographic indices affecting the distribution of grasshopper on the natural grasslands in the upper reaches of Heihe River on the northern slope of Qilian Mountains from July to August 2009, and the relationship between the regional grasshopper number and terrain complexity was also studied, based on the quantitative analysis of the topographic variation characteristics. The topographical factors affecting the grasshopper density were in the order of aspect > elevation > slope > position > plane curvature > profile curvature. The distribution of grasshopper was almost balanced at different gradients of position, plane curvature, and profile curvature, and presented a quadratic parabola distribution at different gradients of aspect and slope and an “S” distribution at different gradients of evaluation. There was a higher grasshopper density in the whole region, but the grasshopper was mainly distributed in the region with an altitude of 2550-2650 m, and concentrated in the northwest and west aspect, which was consistent with the actual observation. The relationships between the grasshopper density and terrain factors and the distribution of the grasshopper indicated that the redistribution of water and heat conditions due to topographic factors caused the diversification and fragmentation of the distribution pattern of the grasshopper.
    Temporal patterns of carabid beetle diversity in agro-landscape in relation to landscape structure.
    ZHANG Xu-zhu, CHANG Hong, ZHANG Xin, DUAN Mei-chun, LI Xiao, YU Zhen-rong, LIU Yun-hui**
    2012, 31(12):  3127-3132. 
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    In May-September 2009, the carabid beetles in the four habitats including maize field, peanut field, orchard, and woodland in Miyun County of Beijing were collected by using pitfall traps, and the seasonal diversity of the carabid beetle population and its predatory guild in the dominant habitat maize field as well as the relationships of this seasonal diversity with the landscape structures in the 100, 250, and 500 m radius were analyzed by the stepwise linear regression analysis. In the four types of habitats, the individual number and species richness of the carabid beetle population and its predatory guild were the maximum in August. The species richness of the carabid beetle population in maize field in May was positively correlated with the landscape connectance index at the scale of 100 m of the sampling plots, whereas the individual number of the carabid beetle population in August showed a negative correlation with the landscape connectance index at the scale of 500 m of the sampling plots. Both the individual number and the species richness of the predatory carabid beetle population in May were positively correlated with the landscape connectance index at the scale of 100 m of the sampling plots, but the species richness of predatory carabid beetle population in August was negatively correlated with the type number of semi-natural habitats at the scale of 100 m of the sampling plots. It was suggested that landscape connectivity and type number of seminatural habitats had significant effects on the diversity of carabid beetle population and its predatory guild in the key stages of their life cycle, and thus, well-considered planning of semi-natural land composition and improved connectance of landscape would promote the maintenance of the diversity of carabid beetle and the exertion of carabid beetle’s pest control function.
    Effects of Asian elephant food source base on the mitigation of human-elephant conflict in Xishuangbanna of Yunnan Province, Southwest China.
    GUO Xian-ming1, HE Qing-cheng2**, WANG Lan-xin1, YANG Zheng-bin1, LI Zhong-yuan3, ZHU Zi-yue4
    2012, 31(12):  3133-3137. 
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    Establishing food source base for Asian elephants is to attract them returning to the depths of nature reserve, and to reduce the human-elephant conflict (HEC). In 2005-2010, a statistical analysis was made on the monitoring data about the activities of Asian elephants in the Mengyang sub-reserve food source base of Xishuangbanna to analyze the activity rhythms of the elephants in the base, and, in combining the cause troubles of the Asian elephants in the surrounding villages of the base, the influences of the food source base on the Asian elephants and surrounding villages were studied, aimed to approach the mitigation effect of the food source base on human-elephant conflict. The food source base supplied large amount of foods to attract Asian elephants, playing definite roles in mitigating the HEC. The monthly and diurnal activity rhythms of the Asian elephants in the base were almost synchronous with the sowing and maturing periods of local crops and the time sequence of the farmers’ routine work. During the period of food shortage, the elephants mainly fed on king grass, a kind of introduced alien plants, or raided into villages to feed crops. The nearer the distance between the food source base and the villages, the more Asian elephant-related cause troubles happened. Therefore, great attentions should be paid to the location layout and the appropriate plant species combination in the establishment of food source base for Asian elephants.
    Present situation of Coilia nasus population features and yield in Yangtze River estuary waters in fishing season.
    LIU Kai, DUAN Jin-rong, XU Dong-po, ZHANG Min-ying, FANG Di-an, SHI Wei-gang**
    2012, 31(12):  3138-3143. 
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    In 2010-2012, investigation sections were installed in the waters of Baoshan and North Channel to study the capture size, population features, and annual yield of Coilia nasus in Yangtze River estuary in fishing season. During the study period, the total length, standard length, and body weight of the C. nasus were averagely 316±36 mm, 294±35 mm, and 99±37 g, respectively. The yield per boat in fishing season ranged from 65.9 to 875.4 kg, with an average of 338.7 kg, the daily catch in fishing season ranged from 2.3 to 23.4 kg, averagely 9.4 kg, and the total licensed catch in fishing season ranged from 8.2 to 109.4 t, with an average of 42.3 t. All the indices related to the yield per boat were lower in Baoshan waters than in North Channel waters. Furthermore, it was found that the fishing season of C. nasus in Yangtze River estuary started earliest in February 23 and latest in March 5, and the peak fishing season usually continued from late March to middle April, with the catch percentage ranged from 60.96% to 82.62%. The results indicated that the catch amount of C. nasus was closely related to water temperature and tide. Generally, the peak fishing season came when the water temperature was up to 12 ℃, and the water temperature corresponding to the maximum daily catch in each year ranged from 13 ℃ to 14.5 ℃, with a mean of 13.7 ℃. During the investigation, the fishing amount at low tide periods had an obviously higher percentage to the total fishing amount in fishing season periods, when compared with that at high tide periods. The maximum percentage of the fishing amount at low tide periods was 82.97%, and the minimum was 62.05%.
    Diversity of invertebrate community in leaf litters of Kunming Arboretum, Yunnan Province of Southwest China.
    WANG Jing1, NIE Jing1, ZHANG Li-min2, XIE Yong-hui1, LI Zheng-yue1,3, ZHANG Hong-rui1,3**
    2012, 31(12):  3144-3149. 
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    An investigation was conducted on the invertebrates in leaf litters under five tree species (Cinnamomum camphora, Sabina chinensis, Magnolia denudata, Pinus yunnanensis, and Acer palmatum cv. Atropuceum) in Kunming Arboretum from May 2010 to September 2011, aimed to understand the community structure and characteristics of the invertebrate assemblages in the leaf litters of the five tree species. A total of 25237 invertebrate individuals belonging to 15 families of 18 orders in 5 classes under 2 phyla were collected, among which, Acarina and Collembola were the dominant groups, while Thysanoptera, Pseudoscorpionidea, Hemiptera, and Dermaptera were the common groups. Shannon diversity index, Pielou evenness index, and Simpson dominance index were used to compare the diversity of the invertebrate assemblages. A similar species composition of the invertebrate assemblages was observed in the leaf litters of the five tree species, and the spatiotemporal heterogeneity of the assemblages was small. In the leaf litters of the five tree species, a total of 375 adult fungus-feeding thrips were collected, belonging to 4 species, 3 genera, and 1 family, in which, Allothrips was the dominant fungusfeeding thrips group, and also, a newly recorded genus for Yunnan Province.
    Diversity of bird communities on the north slope of Taibai Mountain in winter and spring.
    LUO Lei1, ZHAO Hong-feng2, ZHANG Hong3, LI Xian-min3, HOU Yu-bao1, GAO Xue-bin1**, LI Shuang-xi3
    2012, 31(12):  3150-3159. 
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    In the winter (November) of 2009, spring (April) of 2010, and spring (March and April) of 2011, a line transact method was adopted to investigate the bird communities along the north slope of Taibai Mountain, the summit of the Qinling Mountains in Northwest China. Based on the elevation and typical vegetation, six types of habitat were categorized, and representative sampling plots were selected for each habitat type. The relative abundance and estimated area were considered to calculate the relative bird density, and the dominant and common bird species were defined according to the density rank for each habitat type. Over the whole survey period with two seasons, a total of 121 bird species were recorded, belonging to 71 genera, 40 families, and 12 orders, among which, 92 species were residents, 24 species were summer breeders, and 5 species were passaging migrants. Both in winter and in spring, the birds in the habitats were mainly of resident species. There existed definite differences in the density and structure of bird communities in different habitat types within the same seasons and in the same habitat types between different seasons. There also existed differences in the composition of dominant and common bird species between different habitat types and different seasons. Among the habitat types, anthropogenic disturbed deciduous forest had the highest bird diversity index in both winter and spring, and deciduous forest had the highest bird evenness index in the two seasons. The similarity index was generally higher in adjacent habitats than in separate habitats. Except that the bird species number in the mixed forests at medium and high altitudes had somewhat increase over the previous adjacent vegetation type, the bird species richness decreased with increasing altitude, and the bird species composition had greater change, as compared with that between spring and winter.
    Carbon footprint of global electricity and its equivalent calculation.
    FANG Kai1,2, ZHU Xiao-juan2, GAO Kai2, SHEN Wan-bin2**
    2012, 31(12):  3160-3166. 
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    Carbon footprint of electricity is a measurement of the amount of life cycle CO2 emission associated with the whole process of power generation. From the perspective of global carbon cycle,  the characteristics of carbon emission from different power generations are partially the land cover’s carbon sequestration capacity. This paper calculated the average carbon footprint equivalent of global electricity, i.e., the life cycle carbon footprint for per unit of electricity consumed, and analyzed the composition of  carbon footprint of global electricity and its changes in 2000-2008, based on the synthesis of large amount of investigation data. The worldaverage global carbon footprint equivalents of coal, oil, and natural gas used for thermal electricity generation, and of hydroelectricity and nuclear electricity were 131.3×10-6, 95.8×10-6, 56.6×10-6, 38.8×10-6, 1.9×10-6 hm2·(kW·h)-1, respectively, indicating that the environmental impact of thermal electricity, especially coal-based electricity, was significantly greater than that of hydroelectricity and nuclear electricity. From 2000 to 2008, the carbon footprint of global electricity increased from 730.7×106 hm2 to 1101.8×106 hm2, in which, the proportion of thermal electricity increased from 60.0% to 68.1%, in particular coal replaced oil to be the largest source of the carbon footprint of thermal electricity, while the proportion of hydroelectricity and nuclear electricity fell to 30.7% and 1.3%, respectively. Overall, the structure of global electricity revealed a trend towards deterioration, for the worldaverage carbon emission coefficient of electricity increased from 265.8×10-3 kg·(kW·h)-1 in 2000 to 315.4×10-3 kg·(kW·h)-1 in 2008. The results highlight the need for reducing the use of thermal electricity, especially coalbased electricity, which largely determines the intensity and scale of carbon emission from power generation.
    Improvement effects of ecological restoration project ‘returning fishery to lake’ on the water environment of Dalian Lake in Shanghai.
    XU Xia, WANG Qing, LIU Hua, ZHAO Hui, JIANG Hao, LENG Xin, AN Shu-qing**
    2012, 31(12):  3167-3173. 
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    From April 2010 to February 2011, a monthly tracking survey and monitoring was conducted on the ecological restoration project ‘returning fishery to lake’ of Dalian Lake in Shanghai, with the physical and chemical indicators of water environment before and after the implementation of the engineering project compared, aimed to assess the improvement effects of the project on the water environment. As compared with those outside the ecological restoration area, the concentrations of total phosphorous, total nitrogen, NO3--N, and NH4+-N and the COD in the ecological restoration area decreased by 62.5%, 72.2%, 92.9%, 63.3%, and 8.9%, respectively, while the DO increased by 11.1%. In addition, the concentration of chlorophyll a and the abundance and biomass of phytoplankton in the restoration area decreased by 47.7%, 15.3%, and 48.0%, respectively. The integrated water quality identification index of the ecological restoration area was of National class Ⅲ, while that of the control point was of class Ⅳ, and the outlet water quality of the ecological restoration area was obviously better than the inlet water quality. After the implementation of the restoration project, the phytoplankton flora in the restoration area was improved, and the water ecosystem had definite self-purification capacity.
    Responses of soil moisture to bare rocks in Karst rock desertification region of Southwest China during dry season.
    LI Sheng, REN Hua-dong**, YAO Xiao-hua
    2012, 31(12):  3174-3178. 
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    The Karst rock desertification (KRD) in Southwest China is characterized by a large number of rocks cropping out from the ground. To understand the responses of soil moisture to the bare rocks, a monitoring was made on the dynamic changes of soil moisture in a KRD region during an extreme drought period from September 2009 to February 2010. During this drought period, the soil moisture content on the north side of the rocks was significantly higher than that on the east, west, and south sides (P<0.01), and the surface soil moisture content increased with the protruding height of the rocks. There existed significant correlations between the sizes of the bare rocks and the soil moisture content on the west and north sides (P<0.01) and on the east side (P<0.05) of the rocks. Sharper rocks were associated with lower soil moisture content on the east, west, and north sides of the rocks. With the increasing distance from the rocks, the soil moisture content decreased after an initial increase on the north, east, and west sides, but showed an increasing trend on the south side. The soil moisture content around the rocks increased with soil depth. During the drought period, bare rocks presented shading effect, resulting in higher soil moisture content on the north side of the rocks, as compared to the other three sides. The location at 15 cm north of the rocks had the highest soil moisture content, being a favorable site for the vegetation restoration under stressful environmental conditions in the KRD area. These research findings would have significance in the vegetation restoration of the ecosystems damaged by the KRD process.
    Identification and diversity analysis of phytoplasma associated with Praxelis clematidea witch’s broom. 
    LI Guang-ming1,2, YUAN Kun1, YANG Li-fu1, CHEN Qiu-bo1, WANG Zhen-hui1**
    2012, 31(12):  3179-3186. 
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    To study the diversity and classification of phytoplasma associated with Praxelis clematidea witch’s broom is of significance for the biocontrol of the pathogen. In this paper, the P. clematidea plants with the presence of the phytoplasma were collected from eight counties in Hainan Province of South China. The samples were tested by PCR amplification using phytoplasmaspecific 16S rDNA primers. Furthermore, the diversity of the phytoplasma associated with P. clematidea witch’s broom was investigated with restricted fragment length polymorphisms (RFLP) by using the restriction enzymes Afa I, Alu I, EcoR I, Hae Ⅲ, HpaⅡ, Hha I, Hinf I, Kpn I, Sau3A I, Taq I, and Xsp I. The PCR products were cloned and sequenced, and the sequences were compared with the members of 16SrII group of phytoplasma. The results showed that the causal agent of P. clematidea witch’s broom was the phytoplasma. The patterns of RFLP analysis of 16S rDNA sequence primed from the phytoplasma collected from the eight counties were basically the same, and the similarity between the 16S rDNA and that of other known phytoplasmas ranged from 0.26 to 0.97. There was a high similarity (>99.4%) within the sequences from the eight counties, and the highest similarity (99.1%) with the phytoplasma from peanut witch’s broom. It was suggested that the phytoplasma of P. clematidea witch’s broom could be categorized as a branch of 16S rRNAⅡ-A group.
    Ethanol production from Jerusalem artichoke through the fermentation with Saccharomyces cerevisiae and Kluyveromyces.
    HUANG Yu-ling, LONG Xiao-hua**, LIU Zhao-pu, WANG Lin, WANG Bo
    2012, 31(12):  3187-3192. 
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    In order to obtain the optimal combination of bacterial strains for the fermentation production of ethanol from Jerusalem artichoke (Helianthus tuberosus), the recombinant bacterial strain R32 was selected at first to optimize its inulinase producing conditions. The highest inulinase activity of the R32 was 298.8 U·mL-1, and the best culture medium formulae were 1% yeast powder (w/v), 2% peptone (w/v), and 0.5% glycerol (v/v) for YPG culture medium, and 1% yeast powder (w/v), 2% peptone (w/v), and 1% methanol (v/v) for YPM culture medium. The medium pH was the natural initial pH. Then, the Saccharomyces cerevisiae (S.c) and Kluyveromyces (Klu) were selected to compare their ethanol producing capability when fermented separately or in admixture under the conditions of adding R32 crude inulinase broth or not. The results showed that the ethanol production reached the maximum of 11.37% after S.c and Klu being onestep fermented in admixture for 84 h without adding R32 crude inulinase broth, and reached the maximum of 11.43% after S.c and Klu being twostep fermented in admixture for 72 h with the addition of R32 crude inulinase broth. The maximum ethanol yields under the twostep fermentation of S.c and Klu were almost the same. Because of the lower cost and more simplicity of operation, onestep fermentation was more appropriate for the industrial production of ethanol, though it took a longer time. After optimization, the production of ethanol from Jerusalem artichoke by S.c and Klu mixed in onestep fermentation was up to 11.82% under the conditions of 225 g·L-1 of inulin, 40 g·L-1 of urea, 15% of inoculation rate, and pH 5.
    Landscape pattern changes of Xiamen coastal zone and their impacts on local ecological security.
    HUANG Ning1,2**, YANG Mian-hai1, LIN Zhi-lan3, YANG De-wei4, HUANG Yun-feng1,2
    2012, 31(12):  3193-3202. 
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    Coastal zone is a transitional area between land and sea, with intensive human activities and high sensitivity and vulnerability. By using remote sensing images and GIS techniques, this paper studied the dynamic changes of landscape pattern of Xiamen coastal zone during the urbanization from 1987 to 2011, and assessed the impacts of the landscape pattern changes on the local ecological security based on the index system derived from ecological security connotation, the landscape indices, and the ecosystem service value theory. Significant changes of landscape pattern occurred in the study area from 1987 to 2011. The area proportion of construction land was increased by 193.0%, that of arable land and forest land was decreased by 55.2% and 41.4%, respectively, and the mudflat was converted into mariculture area and arable land in the early time and turned into construction land/bare land and water area in the middle and late periods, with a total decrease of mudflat area by 47.1%. Along with the rise and decline of primary industry, the mariculture area was increased first but decreased sharply by 47.6% then. In the early time, the landscape of the study area was diverse, complex in shape, and dispersed in space; while after rapid development, the landscape tended to be simplified and concentrated and had more regular shape, and the natural landscape tended to be highly fragmentized and lowly connected. The changes of the landscape pattern made the ecological security index decreased from 0.561 to 0.430. During the period from 1995 to 2004, the dramatic reduction of mudflat area weakened the natural ecological function, which led to the decline of ecological security. After 2004, with the highly intensive development of the out-island of Xiamen, the natural ecological structure, function, and stability all decreased due to the changes of the connectivity, fragmentation degree, and separating degree of natural landscape and of the holistic landscape shape, including the continuous reduction of mudflat. As a result, the ecological security of the whole coastal zone was getting worse.
    Correlation between the Pb and Cr contents of Wuyi Rock Tea and soil.
    GAO Hai-rong**
    2012, 31(12):  3203-3206. 
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    By using graphite furnace-atomic absorption spectrometry (GFAAS), this paper determined the Pb and Cr contents in the tea and soil samples collected from Wuyi Rock Tea gardens, and, according to the national standards of tea health quality and of the environmental conditions of non-risk tea garden or organic tea garden, the potential risks of the Pb and Cr contents in the tea and soil samples were assessed. The Pb and Cr contents in the tea samples did not surpass the permitted limits of the national standards of tea health quality, and the contents of the two elements in the soil samples were accorded with the national standards of the environmental conditions of non-risk tea garden or organic tea garden. There existed significant positive correlations (P<0.01) between the Pb and Cr contents of the tea samples and corresponding soil samples.
    Available heavy metal concentrations in dominant species rhizospheres of natural vegetations in coal gangue dumps.
    LU Hai-bo, LIU Fang**, ZHU Jian, ZHAO Xiao-yan, CHEN Si-lin
    2012, 31(12):  3207-3212. 
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    An investigation was conducted on the natural vegetations in the coal gangue dumps of three typical coal mine areas in Guiyang City of Guizhou Province, Southwest China, and an analysis was made on the concentrations of 10 available heavy metals in the rhizospheres of five dominant species (Pinus massoniana, Cyclobalanopsis argyrotricha, Betula luminifera, Parathelypteris chinensis, and Neyraudia reynaudiana). No significant differences were observed in the pH and EC between rhizosphere and non-rhizosphere. The concentrations of available Mn, Cd, Ni, Cr, Co, Cu, and Zn were significantly higher in rhizosphere than in nonrhizosphere, but those of available Fe, Pb, and Sb had less difference between rhizosphere and nonrhizosphere. There existed significant differences in the concentrations of available heavy metals in the rhizospheres of different dominant species. The available Mn concentration in N. reynaudiana rhizosphere was significantly higher than that in P. massoniana, C. argyrotricha, and P. chinensis rhizospheres, the available Zn concentration in B. luminifera rhizosphere was significantly higher than that in the rhizospheres of the other dominant species, and the available Cd concentration in B. luminifera rhizosphere was significantly higher than that in P. chinensis rhizosphere. B. luminifera and N. reynaudiana had most obvious rhizospheric effect, being able to be the good candidates for the phytoremediation and ecological restoration of coal gangue dumps.
     
    Assessment of mining area’s ecological vulnerability based on landscape pattern: A case study of Liaoyuan, Jilin Province of Northeast China.
    WU Jian-sheng1, ZONG Min-li1**, PENG Jian2
    2012, 31(12):  3213-3220. 
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    The vulnerability assessment of natural ecosystems in mining areas is of significance in resources management, environmental protection, and regional sustainable development. Based on the analyses of the concepts of ecological vulnerability and the related assessment models, and following the ‘pressurestatusresponse’ (PSR) assessment framework, an assessment indices system was put forward to quantify the vulnerability of natural ecosystems in mining areas from the aspects of human pressure, ecosystem sensitivity, and ecological resilience, with the application of landscape metrics. Taking the Liaoyuan City of Jilin Province as a case, the results showed that among the various types of natural ecosystems, grassland had the highest ecological vulnerability, while forestland had the lowest one. In all the 33 towns, Yangmulin Town had the highest ecological vulnerability, while Dongfeng County town had the lowest one. In the four districts and counties of Liaoyuan, Longshan District had the highest ecological vulnerability, with the Xi’an District, Dongfeng County, and Dongliao County in a descending sequence. The main factors affecting the spatial differentiation of the ecological vulnerability were land use pattern, natural ecological environment, and human disturbances such as mining and settlement.
    Bacterial diversity in bore holes of gas hydrate-rich deposit districts in Qilian Mountains of Northwest China.
    WU Shu-jiao1, HAN Lu1, LU Jie1**, DONG Jian-ying1, ZHU You-hai2
    2012, 31(12):  3221-3227. 
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    In this study, four core samples were collected from the DK-6 bore holes of gas hydrate-rich deposit districts in the permafrost zone of Qilian Mountains, Qinghai Province of Northwest China, with the total bacterial genome in the samples analyzed. Four 16S rDNA gene libraries were created by PCR. There were 44 OTUs, including five categories, i.e., Firmicutes, Bacteroidetes, Proteobacteria (α-, β-, and γ-Proteobacteria), Actinobacteria, and Deinococcus-Thermus, in the four gene libraries. The microbial communities of different lithology showed a relatively large composition difference, and had different dominant species. Lithology played a certain decisive role to the growth of bacteria. Bore holes DK6-12 (117.5 m) and DK6-17 (161.9 m) were of mudstone, in which, Alcaligenes xylosoxidans was the dominant bacterium. K6-23 (194.6 m) was of fine sandstone, in which, a large number of Spirosoma panaciterrae was found in cloning sequences. DK6-25 (213 m) was of coal, with the highest abundance of Pantoea ananatis. Most of the microbes presented in the four samples could metabolize organic hydrocarbon. Our results indicated that in the gas hydrate-rich deposit districts in permafrost zone, environmental factors limited the diversity of microbes.
    Fate and ecological toxicity of fluoroquinolone antibiotics in soil: A review.
    GUAN He-lan*, YU Hai-feng, WANG Jia-yu
    2012, 31(12):  3228-3234. 
    Asbtract ( 1999 )   PDF (528KB) ( 619 )  
    Fluoroquinolone antibiotics are the highly efficient and broad-spectrum antibacterial agents in treating the bacterial infection of human beings and animals, being widely used in clinic because of their good pharmacokinetic characteristics and curative effect. After entering into soil, the residues of fluoroquinolone antibiotics undergo a series of transformation processes such as adsorption, degradation, and plant uptake. This paper summarized the key pollution sources of fluoroquinolone antibiotics in soil and a series of the transformation processes of the antibiotics in soil, such as adsorption, degradation, and plant adsorption and accumulation, and discussed the ecological effects caused by the residue of fluoroquinolone antibiotics in soil, aimed to provide evidence for the prevention and remediation of soil fluoroquinolone pollution.
    Life skill trainings for hatchery fish to improve its foraging and anti-predation capability in natural environment: A review.
    SHI Xiao-tao1,2, CHEN Qiu-wen1,2**, ZHUANG Ping3, LIU De-fu1, HUANG Ying-ping1
    2012, 31(12):  3235-3240. 
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    The artificial proliferation and release of hatchery fish has not achieved expected results, primarily due to the low survival rate of the fish after released into natural environment. The life skill trainings for the hatchery fish before its release may have active effects on the improvement of the survival rate of post-release. This paper analyzed the reasons for the low survival rate of fish post-release, and pointed out that foraging and anti-predation capability was one of the key factors affecting the survival rate of fish post-release. The key factors affecting the foraging and anti-predation capability, including prey and predator recognition, social learning experience, environmental complexity, and fish swimming ability were discussed, and the innovative training techniques leading to a higher fish postrelease survival rate were suggested.
    Neutral landscape models in landscape ecology: Application and development.
    WU Hai-feng1,2, LI Yue-hui1**, LI Na-na1,2
    2012, 31(12):  3241-3246. 
    Asbtract ( 1992 )   PDF (437KB) ( 449 )  
    Neutral landscape models (NLMs) can be served as one of the important tools in landscape ecology to generate a series of patterns with similar statistic characteristics while neglecting specific ecological or physical geographical processes, providing a reference for exploring real landscape pattern. Recently, NLMs have become an increasingly important role in landscape ecology, and have been used in creating and calibrating landscape metrics and in investigating the effects of landscape patterns on population dynamics and the disturbance processes. This paper reviewed the origin, connotation, and development of NLMs, elaborated on the application of NLMs. Tthe further research should aim, to improve the complexity in the structure of NLMs for examining various real landscapes, to validate the simulation results of NLMs, and to explore the interactions between landscape pattern and processes by incorporating NLMs with other existing research methods in landscape ecology.