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    10 May 2014, Volume 33 Issue 5
    Niche characteristics of dominant woody plant populations in a Torreya fargesii shrub community in the Jinfo Mountains.
    WANG Jian-hua, ZHOU Xian-rong**, SHANG Jin, JIANG Bo, YANG Li-ping
    2014, 33(5):  1135-1141. 
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    We investigated the niche characteristics of the dominant woody plant populations in a Torreya fargesii shrub community in the Jinfo Mountains based on the formulae by Levins and Hurlbert for niche breadth and Pianka’s niche overlap. Our results showed that the T. fargesii importance value (IV) was the largest in the community. The niche breadths for Ligustrum sinense, Rubus coreanus, T. fargesii, Cotoneaster horizontalis, Hypericum monogynum, Nothopanax delavayi, Zanthoxylum ovalifolium and Viburnum chinshanense were relatively greater than those for the other populations. There was a weak positive correlation between the niche breadth and the IV, and a negative correlation between the species’ niche breadth and the variance coefficient of the IV. Of the 253 species pairs, 160 pairs overlapped > 0.6, occupying 63.24% of the total species pairs. There were relatively high niche overlaps among most of the populations, and C. horizontalis, L. sinense, H. monogynum, R. coreanus, Z. ovalifolium, V. chinshanense populations with broad niche breadth had greater overlaps with the T. fargesii population. These results indicated that intense resource competition occurs among populations.
    Herbaceous species diversity and community quantitative analysis in the riparian zone of East Liaohe River.
    ZHANG Wen-li1,4, XIA Hui-juan1,2,3, ZHANG Yuan2,3, KONG Wei-jing2,3**, JIA Xiao-bo2,3, YAO Yi-han2,3
    2014, 33(5):  1142-1149. 
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    Herbaceous species diversity and herbaceous community quantitative features in the riparian zone of East Liaohe River were studied with the sample line approach. To find the major environmental factors affecting the distribution pattern of riparian herbaceous communities, cluster analysis and ordination analysis were conducted by using group average clustering analysis and detrended correspondence analysis (DCA). Results showed that there were altogether 118 herbaceous species, belonging to 36 families and 70 genera. The herbaceous species diversity increased firstly and then decreased from upstream to downstream, while the richness index changed irregularly due to hydrological characteristics, riparian substrate types, soil moisture and human disturbance. The herbaceous communities were classified into 11 types using clustering analysis, and dominated by hygrophytes. Correlations between DCA ordination axes and environmental factors showed that the elevation and stream order were the major environmental factors affecting the distribution pattern of herbaceous communities in the riparian zone of East Liaohe River.
    Effect of climate factors on Mytilaria laosensis population and distribution forecasting in the future.
    PENG Ji-qing, CAO Fu-xiang**, DUAN Hui-liang, DONG Xu-jie
    2014, 33(5):  1150-1156. 
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    In order to investigate the influence induced by climate change on the forest vegetation in the subtropical area and the response of the forest vegetation to climate change, the genetic diversities of Mytilaria laosensis population in provenance and cultivation areas were studied by ISSR molecular marker technique. The meteorological factors in the cultivation areas were associatively analyzed. The results analyzed by PopGen32 software package showed that the genetic diversities of the cultivation populations (Xinning population and Zhuzhou population, Hunan) and provenance population (Pingxiang population, Guangxi) of M. laosensis are basically consistent due to the time for M. laosensis population introduction in Zhuzhou, Hunan during the warming period when various climate factors were no longer limiting factors to affect the growth of M. laosensis population. The climate in 2042 was simulated by the RegCM3 climate model. Compared to the climate in 2010, annual average temperature would increase by 1 ℃, average temperature in January would obviously rise, while average temperature in July would have little change in the south of the Nanling Mountain but obviously increase in the north, and annual precipitation would have no obvious variation. It is expected that the natural population of M. laosensis may distribute to approximately 25°N in 2042, and distribute sporadically in the north of 25°N, while in coastal areas, the distribution would further northerly extend up to about 26°N.
    Spatial genetic patterns of four alpine plants in Tibetan Plateau based on GIS.
    YU Hai-bin1,2, ZHANG Yi-li1**, LIU Lin-shan1, QI Wei1,2
    2014, 33(5):  1157-1163. 
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    The rapid uplift of Tibetan Plateau and climatic oscillations of the Quaternary dramatically shaped contemporary genetic patterns of alpine plants in Tibetan Plateau. The genetic diversity and divergence landscape patterns and the identified geographical isolation of four species containing Pedicularis longiflora, Rhodiola alsia, Sibiraea angustata and Hippophae tibetana were attained using the spatial interpolation method and Monmonier’s algorithm based on cpDNA variation. The results showed that the high genetic diversity and divergence areas were mainly highlighted within East HimalayasHengduan Mountains (HHM) region. The geographical isolation of each species was also found within the HHM region. Partial Mantel test showed that the geographical isolation had significant influence on gene flow between populations of the four species. These results verified that long-term geographical isolation resulted in high genetic divergence and diversity patterns in HHM region.
     
    Effects of morphological adjustment on establishment of Haloxylon ammodendron.
    TIAN Yuan1,2,3, TASHPOLAT Tiyip1,4**, LI Yan2,3, XU Gui-qing2,3
    2014, 33(5):  1164-1169. 
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    Due to climate change and heavy human activities, the precipitation and groundwater at the southern edge of the Gurbantunggut desert have significantly changed, which would affect the water use strategy of local plants. In this study, Haloxylon ammodendron, which is the constructive species in the southern edge of the Gurbantunggut desert, was taken as the study object. A consecutive investigation on seed germination, meteorological factors, aboveground height, belowground depth and plant biomass was carried out until the establishment of plant, to reveal its growth traits and adaptability during the whole establishment process. The results showed that diebacks of the assimilating branches in drought period could maintain the balance between water supply of roots and water consumption of the assimilating organs. This morphological adjustment ensured the photosynthetic ability of survival organs. Furthermore, the allocation of more photosynthates toward roots could ensure H. ammodendron survival during drought and recovering when water conditions become better.
     
    The response of understory plant diversity and nutrient accumulation to stand structure of poplar plantation.
    YAN Ya-fei1,2, FANG Sheng-zuo1**, TIAN Ye1, SONG Hao1, DUN Xing-jian1
    2014, 33(5):  1170-1177. 
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    Poplar (Nanlin-95) plantations with different stand densities and spacing were investigated to study the effects of stand structure on understory characteristics in Chenwei Forest Farm, Sihong County, Jiangsu Province. The results showed that the Shannon index of the understory was higher under the low density stands than under the high density ones, while the distribution of understory was much homogeneous under high density stands, with a higher Pielou evenness index. The diversity index of the understory was lower in May than in November. The biomass of the understory was higher in the low density stands than in the high density stands. Low stand densities increased the concentration and accumulation of N, P, K, and Mg in understory, while no significant effects of stand structure were detected on the concentration and accumulation of Ca in understory. The concentration and accumulation of N, P, and Ca were higher in May than in November while the concentration and accumulation of K and Mg were lower in May than in November.
    Spring canopy interception characteristics of Phyllostachys praecox cv. Prevernalis stand converted from cropland at different densities.
    ZENG Wei, XIONG Cai-yun, XIAO Fu-ming**, YU Lin, XIONG Zhen-yu
    2014, 33(5):  1178-1182. 
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    A hydrological observation in Phyllostachys praecox cv. Prevernalis stands converted from croplands at eight different densities (10800±400, 11600±400, 13200±400, 14800±400, 16400±400, 20800±400, 22400±400, 22800±400 individuals per hm-2) was carried out to study their canopy interception characteristics. The results showed that the rainfall had a parabolic relationship with throughfall and stemflow, and had a downward parabolic relationship with canopy interception, respectively. The average rate of canopy interception of the eight stands ranged from 1.42% to 37.58%, and the stand density had a downward parabolic relationship with the maximum canopy interception and average canopy interception rate. At the stand density of 17209 individuals per hm-2, the average canopy interception rate was maximum (31.15%) and the maximum canopy interception potential was 39.07 mm. Therefore, a proper stand density could fully favor the ecohydrological benefit of P. praecox cv. Prevernalis stands.
     
    Comparison of growth characteristics between 1-year-old seedlings of Quercus mongolica through seed germination and sprout regeneration.
    GANG Qun1,2,3, YAN Qiao-ling1,2**, LIU Huan-bin4, ZHANG Min1,2
    2014, 33(5):  1183-1189. 
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    This study aimed to explore the differences in morphology and nutrient distribution of Quercus mongolica seedlings from two regeneration types (i.e., seed regeneration and sprout regeneration) by comparing the growth characteristics of 1-year-old seedlings and sprouts in a montane region of eastern Liaoning Province, China. The results showed that there were significant differences in biomass between seedlings and sprouts. Specifically, the leaf weight, stem weight,  and stem weight to aboveground biomass ratio of sprouts were significantly greater than those of seedlings (P<0.05). leaf weight to above ground biomass ratio, Photosynthetic tissuetononphotosynthetic tissue ratio of seedlings were significantly higher than those of sprouts (P<0.05). The growth traits of sprouts were characterized by short and thick stems while the seedlings exhibited tall and small stems with thick and long roots. There were no significant differences in specific leaf area, nitrogen content and δ13C in leaf between seedlings and sprouts (P>0.05). The water content of sprouts was significantly greater than that of seedlings (P<0.05). There were no significant differences in the contents of structural carbon and nonstructural carbon between seedlings and sprouts (P>0.05). However, the sprouts had significantly less soluble sugar contents in leaf and stem, and a significantly greater starch pool in leaf than the seedlings (P<0.05). It can be concluded that there are different growth strategies to acclimating the local environments for seedlings of Q. mongolica from two regeneration types. Sprouts of Q. mongolica sustain their growth relying on the nutrients and water supplied by parent plants, meanwhile, much more starch produced by photosynthesis is stored in their leaves. However, the seedlings of Q. mongolica tend to raise the growth of stem and the biomass of photosynthetic tissue to most utilize light resources, meanwhile, much more soluble sugar is stored in leaves and stems to maintain their growth.
    Seed germination of invasive species Galinsoga parviflora under drought stress simulated by PEG.
    QI Shu-yan1,2**, DUAN Ji-peng1, GUO Ting-ting1, DONG Jing-jing1
    2014, 33(5):  1190-1194. 
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    5%, 10%, 15%, 20% and 25% PEG-6000 solutions were used to simulate drought stress conditions for the germination of Galinsoga parviflora. Germination time, germination percentage, daily relative germination rate, germination potential, germination index and vigor index under each water stress were recorded. The effects of drought stress through PEG treatment on seed germination, and the germination recovery under optimal conditions after presoaking with PEG solution were studied in a series of laboratory tests. The results showed that as the water stress was aggravated, the seed germination and seedling growth were more seriously inhibited, and daily relative germination rate, germination percentage, germination potential, germination index, vigor index, and the length of seedlings and roots were decreased, and germination time was extended longer. When the PEG concentration was 20% or 25%, the seeds of G. parviflora did not germinate. The linear regression equation of seed germination under water stress predicted that the critical value of PEG concentration (drought tolerance) was 12.9%. The seeds recovered their germination under optimal conditions after presoaking with 20% or 25% PEG solution. Nevertheless, when the presoaking time was same, 20% PEG solution had little effects on the seed germination of G. parviflora, showing a strong recovery, while 25% PEG solution had adverse effects on the seed germination of G. parviflora, showing a weak recovery.

     
    Responses of cotton growth and water physiological indices to salt stress at different growing stages.
    FENG Di1, ZHANG Jun-peng1, SUN Chi-tao1, DANG Hong-kai2, LIU Hao1, NING Hui-feng1, SUN Jing-sheng1**, LI Ke-jiang2
    2014, 33(5):  1195-1199. 
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    In order to explore the water regulation mechanism of cotton under salt stress at different growing stages, a potted experiment was conducted to study the shortterm responses of cotton (Jimian 616) growth and water physiological indices to various salinities of irrigation water (NaCl) at different growing stages. The results indicated that when the salinity of irrigation water reached 4 g·L-1, cotton vegetative growth was restrained; however, the reproductive indices (bud stage and blossoming and bollforming stage) were not affected significantly. The growing process was not affected at the bud stage, delayed at emergence and seedling stages but advanced at blossoming and bollforming stages. In addition, with the increase of irrigation water salinity, stomatal resistance increased at the seedling stage, bud stage, and blossoming and bollforming stage. However, the relative leaf chlorophyll content increased at the seedling stage, first increased and then decreased at the bud stage, decreased at blossoming and bollforming stages, respectively. Salt stress increased the dry weight to fresh weight ratio of all organs except leaves during the whole study period, and the dry weight to fresh weight ratio of leaves basically kept stable. Our results suggest that water in cotton plant could be supplied to leaves preferentially and leaf transpiration was reduced through a water regulation mechanism when cotton was in salt stress.
     
    Root physiological characteristics and yield of maize with different cultivation durations in alfalfa stubble land.
    ZHANG Yu-qin1**, YANG Heng-shan1, FAN Xiu-yan1, GAO Ju-lin2
    2014, 33(5):  1200-1204. 
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    High-yield maize was planted in a preceding 7-year-old alfalfa land for four consecutive years, and the vertical distribution of root, physiological characteristics of root and yield of maize were measured. The results showed that the maize yield and the root dry weight at the silking and milking stages decreased with the cultivation years, and the difference of the root dry weight in the different years were more obvious with the increase of soil depth. The percentage of root biomass at the 0-20 cm soil layer to the total root biomass (0-60 cm) increased with the cultivation years. The root activity and SOD activity at the silking and milking stages decreased with the cultivation years. The POD activity of maize roots at the silking stage decreased with the cultivation years except for the 20-60 cm soil layer. The MDA contents of maize roots in different soil layers at the milking stage increased with the cultivation years, and the differences among the different cultivation years were more obvious with increasing the soil depth.
    Response of litter production and its seasonality to increased nitrogen deposition in a subtropical evergreen broad-leaved forest.
    ZHANG Chi1, ZHANG Lin1, LI Peng2, SHI Wen-tao1, XU Xiao-niu1**
    2014, 33(5):  1205-1210. 
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    A field simulated experiment was conducted to study the effects of nitrogen deposition on the litter production of a subtropical evergreen broad-leaved forest. Treatments were designed as CK (0 kg·hm-2·a-1), low N (LN, 50 kg·hm-2·a-1), high N (HN, 100 kg·hm-2·a-1), high N+P (HN+P, 100 kg N·hm-2·a-1 + 50 kg P·hm-2·a-1), with three replicates for each treatment. The results from a twoyear observation showed that the annual litterfall production amounts were 7.78, 8.81, 9.08 and 9.41 t·hm-2 for CK, LN, HN and HN+P, respectively. The N deposition did not significantly increase litterfall production in this subtropical forest. However, HN treatment decreased the production of foliar litterfall compared to LN treatment. The production of either foliar, branch or total litterfall was higher in HN+P treatment than in HN and LN treatments, indicating that P addition enhanced litterfall production. The monthly litterfall in all treatments showed similar seasonal patterns, with two peaks occurring in April to May and in November. Within litterfall components, foliar litter accounted for 53.78%-58.84%, sexual organs and miscellaneous accounted for 28.29%-33.66%, and branch accounted for 10.79%-12.87%. Results from this study demonstrated that high N treatment could result in excess N and imbalance of N and P in soils.
    Soil NH4+-N and NO3--N distribution of different vegetation types in water conservation forests.
    GAO Hong-cui1,3, FAN Zhi-Ping1,2**, LI Fa-yun2, LI Hai-yan4, XU Ying-hua4
    2014, 33(5):  1211-1216. 
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    In this paper, we analyzed soil inorganic nitrogen (NH4+-N, NO3--N), pH, bulk density, organic carbon and total nitrogen in four waterconservation forests (e.g. Acer mono-Quercus mongolica forest, Populus davidiana forest, Betula platyphylla-P. davidiana forest, and Larix kaempferi plantation) in the mountain area of eastern Liaoning, to reveal the relationships of vegetation type with soil layer and soil inorganic nitrogen distribution. Results indicated that the concentrations of soil NH4+-N and NO3--N were highest in the Oa horizon (0-5 cm) and decreased gradually in the mineral soil layers. Soil inorganic nitrogen concentration was in a sequence of L. kaempferi plantation (27.46 mg·kg-1) > P davidiana forest (21.76 mg·kg-1) > A. mono-Q. mongolica forest (19.09 mg·kg-1) > B. platyphylla-P. davidiana forest (17.88 mg·kg-1). NH4+-N was the major form of soil inorganic nitrogen in the broadleaved forests, while NO3--N was dominant in L. kaempferi plantation soil. There was a highly significant positive correlation between soil inorganic nitrogen and organic carbon or soil moisture in the four forest types (P<0.01). Overall, vegetation type greatly affected the distribution of soil inorganic nitrogen. Our results can provide a reference for vegetation type selection and structural regulation of water conservation forests in the mountainous area of eastern Liaoning.
    Effect of cadmium stress on antioxidative system in tobacco callus.
    GAO Yang, LOU Hong, LI Shu-yuan, WANG Hong-yan, RUAN Ya-nan**
    2014, 33(5):  1217-1223. 
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    Cadmium is a non-essential element for plant growth, however, it could be absorbed and remained easily, and make an obvious damage to tobacco (Nicotiana tabacum L.). In this study, tobacco leaves were induced to produce callus by the minimal medium (MS + 1.0 mg·L-1 6BA + 0.5 mg·L-1 NAA). After 45 days, with a large amount of callus, the activities of related enzymes (SOD, CAT, APX, MDAR, GR and DHAR) in the antioxidant system, the levels of reactive oxygen species (O-·2, H2O2), and malondialdehyde (MDA) content were measured every three days. The results showed that the reactive oxygen species enhanced, and the activities of antioxidantive enzymes increased in tobacco callus under the cadmium stress within 45-51 days. However, after 51-57 days the activities of antioxidantive system, and membrane lipid peroxidation were aggravated, indicating that the increasing activities of antioxidantive system could not resist the longterm (54-57 days) high cadmium stress.
    Community structure of macrozoobenthos and bioassessment of water quality in Lake Changdang, Jiangsu Province.
    CAI Yong-jiu1,2, LIU Jing-song3, DAI Xiao-ling3, XU Hao1, XUE Qing-ju1, GONG Zhi-jun1**
    2014, 33(5):  1224-1232. 
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    Macrozoobenthic assemblages were investigated monthly in Lake Changdang from June 2011 to May 2012, and bioassessment of water quality was conducted based on biological indexes. A total of 28 taxa were identified, including 10 Chironomidae larvae, 7 Oligochaetes, 5 molluscs and 6 other species. Bellamya aeruginosa, Limnodrilus hoffmeisteri, Tanypus chinensis, Microchironomus tabarui, Branchiura sowerbyi and Chironomus semireductus dominated the community with high abundance and biomass. Annual average density and biomass of macrozoobenthos were 769 ind·m-2 and 74.89 g·m-2, respectively. Marked spatial differences were found for the annual average density and biomass of macrozoobenthos in Lake Changdang with a higher spatial difference for the mean biomass than for the mean density. Higher mean biomass values were found in littoral sampling sites but lower values in open lake sampling sites. The results of Wright index, Goodnight-Whitley index, BPI index (biological pollution index) and Shannon index suggested that Lake Changdang suffered slight to moderate pollution.
    Health assessment of mariculture ecosystem in Shen’ao Bay.
    XIE Ling1, LI Hai-yan2, XU Hua-bing1, ZHONG Ming-qi2, CHEN Wei-zhou1, DU Hong2**
    2014, 33(5):  1233-1242. 
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    Shen’ao Bay is one of the typical marine culture bases in the eastern Guangdong Province. Long-term mariculture activities lead to some environmental problems, such as eutrophication. In this paper, the pressurestateresponse model (PSR) was used to evaluate the health status of mariculture ecosystem in Shen’ao Bay with the fuzzy comprehensive evaluation method. The results showed the membership of Shen’ao Bay was 0.4983, suggesting that the ecosystem was in a very healthy state. The maximum memberships of the seven ecological elements were 0.5717, 0.3714, 0.5215, 0.5942, 0.6014, 0.7792, and 0.6562, respectively. Except that the membership of direct pressure element was in unhealthy and subhealth states, the other remained elements were above healthy levels. The main factors affecting the overall healthy status of the ecosystem included the excessive varieties of cultivation and the excessively large cultivation area. In addition, the low primary productivity and the low annual growth rate of aquaculture production contributed, to some extent, to the overall unhealthy status.
     
    Spatiotemporal patterns of fishing grounds of tuna longline fishery in the mid-eastern Pacific Ocean.
    HUA Cheng-jun1, ZHANG Heng1**, WU Yu-mei1, FAN Xiu-mei1, YE Shou-jian2, XU Liang-qi2
    2014, 33(5):  1243-1247. 
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    The present study explored the seasonal and interannual patterns of fishing grounds of tuna longline fishery in the mid-eastern Pacific Ocean according to the catch data of tuna fishing (June 2009 to January 2012) from five vessels of Shanghai Jinyou Fishing Company, and examined the correlations between the catch and sea surface temperature (SST) obtained by satellite remote sensing. The results sho〖JP2〗wed that the location of the central fishing ground shifted from the east in 2009 to the west in 2010 and 2011. In general, the catch rate of tuna and the optimal SST in the central fishing ground were higher in the El Ni-o year (2009) than in the La Ni- years (2010-2011). The optimum range of SST of fishing ground was 25-30 ℃. It was found that the mean catch had a significant positive correlation with the mean monthly SST (P<0.05).
    The lateralization of escape movement and its stability in juvenile Spinibarbus sinensis.
    PENG Jing, CAO Zhen-dong, FU Shi-jian**
    2014, 33(5):  1248-1252. 
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    The locomotive lateralization in certain individuals among a fish population is often relative to predatory tactic and predator escape strategy. To investigate whether the locomotive lateralization exhibited in Spinibarbus sinensis (evaluated by if the individual fish run to the same direction more than 8 times out of 10 Tdetour trails), we selected 40 S. sinensis and reared individually at 20±1.0 ℃, and then we performed 10 detour trails in each individual for scoring the direction. To investigate the repeatability of locomotive lateralization, we repeated 10 detour trails by 3 more times at 3-day interval (4 series in total). Taking the 4 series as a whole, (53.4 ±3.8)% individuals exhibited lateralization with either left (19.2±1.3)% or right (34.2±4.0)% preference. Furthermore, there was no significant difference in relative lateralization index (LR) among four series. However, after marked repeating with 3 series, the proportion of individuals keeping initial direction significantly decreased from 45.0% at the first series to 21.0% (P<0.05), 16.7% and 17.1% at the second to fourth series, respectively. The proportions of individuals showing stabilized left and right lateralization were both 8.57%. It was suggested that locomotive lateralization exhibited in certain individuals of S. sinensis. However, the individuals exhibiting stabilized lateralization were much less than other fish species, suggesting that locomotive lateralization may have little contribution to the survival fitness of S. sinensis. Furthermore, the results suggested that marked repeating test was important for assessing the locomotive lateralization.
    Effects of mulching management on leaf nutrition quality of Phyllostachys violascens and leaf palatability to leaf-eating insects.
    CHEN Shan, CHEN Shuang-lin**, GUO Zi-wu
    2014, 33(5):  1253-1259. 
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    Mulching with organic matters (rice straw and rice hull) in winter is a management technology to promote the early growth of bamboo shoots. To understand the occurrence of leafeating insects under the influence of mulching management, the effects of mulching on leaf nutrition quality and leaf palatability to the leafeating insects were analyzed. The contents of C, N, P, structural carbohydrates, nonstructural carbohydrates, chemical defense substances in leaves of 1-3 years old Phyllostachys violascens from bamboo stands with different mulching managements, including the respitemulching (3-year mulching + 3-year respite), long-term mulching (consecutive 6-year -ulching) and non mulching (CK) were determined. The results showed that, compared with CK, the respitemulching treatment did not affect C concentration in leaves of 1-3 years old culms, but led to a decline in starch, cellulose and phenolic acids. Other indexes of 2 and 3 years old culms and lignin, oxalic acid of 1 year old culms in respitemulching treatment were higher compared to CK, while no difference was found in other indexes of 1 year old culms. On the other hand, the long-term mulching treatment did not change leaf phenolic acid concentration of 1 and 2 years old culms, but lead to an increase in P, oxalic acid and lignin, and a decrease of other indexes. P, sucrose, lignin, oxalic acid, phenolic acid increased, while other indexes of 3 years old culms decreased in the long-term mulching treatment. Furthermore, long-term mulching treatment influenced the nutrient balance of leaf C, N, and P obviously. All results indicated that the mulching management had a significant influence on the leaf nutrition quality and leaf palatability to leaf-eating insects. Leaf nutrition quality and defense ability were enhanced in the respite-mulching stand while the long-term mulching stand was easier to induce the occurrence and outbreak of leaf-eating insects.
    Electroantennogram and behavioral responses of Tomicus minor (Hartig) (Coleoptera: Scolytidae) to plant volatiles.
    WANG Hong-wei1, YANG Wei1**, YANG Hua1, YANG Chun-ping1, ZHU Xiao-qing1, LIU Feng-jian1, JIANG Li-hua2, SHAN Chun-yan2
    2014, 33(5):  1260-1266. 
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    In order to screen out the effective compounds for preparation of attractants to trap female and male Tomicus minor (Hartig), the electroantennogram (EAG) and behavioral responses of female and male adults of T. minor to volatiles of its plant host, Pinus yunnanensis Franchet were tested. The results showed that all the 9 tested plant volatiles could induce the EAG responses at 10 g·L-1 compared with the control, and the EAG responses of the antennas caused by the different volatiles had significant differences (P<0.05). The female and male adults of T. minor exhibited strong EAG responses to (+)-α-pinene, (+)-limonene, (+)-3-carene, β-pinene and terpinolene; In the dose response tests, the EAG responses of female and male adults to (+)-α-pinene, (+)-limonene, (+)-3-carene and β-pinene intensified with the increasing concentration. When the concentration increased to 10 g·L-1, the EAG response was the strongest; however, the females and males showed the strongest EAG responses to terpinolene at the concentration of 1 g·L-1. Furthermore, T. minor showed no distinct directional behavior to the (+)-limonene; however, (+)-α-pinene, β-pinene, (+)-3-carene and terpinolene could obviously allure the females and males. The Duncan’s multiple range test for the behavioral response of females and males to the five plant volatiles showed that (+)-αpinene had the greatest attracting effect on females and males at 10 g·L-1 concentration. Our study provides a reference for developing attractive chemicals for T. minor in forests.
     
    Genetic variation of Eulecanium giganteum (Shinji) geographical populations and its correlations with ecological factors.
    ZHU Xin-shuai, WANG Deng-yuan**, YU Jiang-nan
    2014, 33(5):  1267-1273. 
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    The genetic diversity of 15 Eulecanium giganteum (Shinji) populations, which were collected from five regions (Hami, Bazhou, Akesu, Kashi and Hetian) of Xinjiang, was investigated by using intersimple sequence repeat (ISSR) markers. The results showed that Shaya population in Akesu had the highest genetic diversity, while Hejing population in Bazhou had the lowest genetic diversity. Correlation analysis showed that the genetic diversity of E. giganteum populations was positively correlated with the annual mean air temperature and humidity, but less correlated with the age of host tree and latitude, and negatively correlated with the elevation. Besides, the genetic distance between the paired populations was positively correlated with the annual mean air temperature. Coccid occurred severely on the south side and middle parts of trees.
     
    Effect of purple soil organic matter on adsorption and desorption of Pb2+ by aggregates.
    LI Lu-juan, XIA Jian-guo**, LIU Lang
    2014, 33(5):  1274-1283. 
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    The purple soils collected from four land-use types, including tea garden, dry land, paddy field and woodland in the Mingshan River watershed, were used to investigate the effect of purple soil aggregate components on the adsorption and desorption of Pd2+ by aggregates using the isothermal adsorption method of equilibrium and the desorption method of NH4OAc and EDTA. The results showed that before and after removing organic matter, the absorbance of Pd2+ by differently sized aggregates increased with the initial Pd2+ concentration, in a sequence of (<0.002 mm) > 2-0.25 mm > bulk soil > 0.053-0.002 mm > 0.25-0.053 mm. The Freundlich equation was the best to fit the adsorption pattern. The distribution coefficient Kd was negatively correlated with the initial Pb2+ concentration. Woodland soil showed the maximum capacity of Pb2+ adsorption while tea garden soil showed the minimum. The adsorption was mainly based on electrostatic adsorption, supplemented by complexation adsorption. The nondesorption rate was in order of woodland > dry land > paddy field > tea garden, indicating that the holding capacity of the tea garden soil was the weakest and woodland soil was the strongest. After removing the organic matter, the Pd2+ absorbance by differently sized aggregates all decreased. The adsorption reductions of woodland and dry land soils were more obvious compared with those of tea garden and paddy soils. The reduction of maximum adsorption had a significant positive correlation with the amount of organic matter removal. In purple soils of the four landuse types, NH4OAc desorption rate increased obviously while EDTA desorption rate decreased accordingly, and the nondesorption rate decreased in varying degrees.
    Effects of water table and fertilization on organic carbon fractions in paddy soil.
    YI Ya-nan, YIN Li-chu**, ZHANG Lei
    2014, 33(5):  1284-1289. 
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    In order to explore the effects of different water tables (low water-table of 80 cm, high water-table of 20 cm) and fertilization treatments (high application of crop residue, common application of crop residue, and chemical fertilizer) on physically divided organic carbon fractions (free particulate organic carbon, fPOC; occluded particulate organic carbon, oPOC; and mineral combined organic carbon MOC), different organic carbon fractions of top soil were measured in a long-term field experiment initiated in 1981. The results showed that the content of particulate organic carbon (POC) was between 6.29-11.77 g·kg-1 and increased with the amount of the application of crop residue. Moreover, the increment of POC content under the three fertilization treatments at the high watertable was greater than at the low watertable. Treatments with crop residue had a much higher percentage of POC (fPOC/TOC, oPOC/TOC) than those with chemical fertilizer at each of the two watertables, especially at the low water-table. Each organic carbon fraction had a very significant correlation with the soil total organic carbon (TOC) and the organic carbon combined with aggregates with particle size >2 mm. Applying crop residue can improve soil TOC and POC both at high and low water-tables, especially at the high water-table.
    The variation of soil inorganic carbon of alpine meadow at different degeneration stages in Qinghai Province.
    LIU Shu-li1,2, LIN Li1, DU Yan-gong1, LI Yi-kang1, ZHANG Fa-wei1, GUO Xiao-wei1,2, OUYANG Jing-zheng1,2, CAO Guang-min1**
    2014, 33(5):  1290-1296. 
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    In this study, the spatiotemporal transformation method was used to investigate soil inorganic carbon (SIC) storage and content of alpine meadow at different degraded stages in Qinghai Province. We collected soil samples of alpine meadow degraded at four different stages, namely, grass-Kobresia humilis grassland, alpine normal meadow, eroded alpinetype black beach, and degraded grassland. Our results showed that in the 0-50 cm soil profile, the SIC values of the grass-K. humilis grassland, alpine normal meadow, eroded alpinetype black beach, and degraded grassland were 0.45, 0.10, 0.13 and 1.10 kg C·m-2, respectively. A carbonates deposited layer was found below the 30 cm soil depth in the grass-K. humilis and degraded grasslands. No such obvious SIC concentration layer was observed in the alpine normal meadow and eroded alpinetype black beach. There was a coevolutionary relationship between the characteristics of mettic peipedon (thickness and fragmentation), bulk density, pH and the characteristics of SIC change. No obvious coupling relationship was found between the degeneration of the alpine meadow and the SIC storage. The storage of SIC would change when an extreme degradation of the meadow occurred.
    Effects of land use on soil organic carbon and its turnover rate in Karst mountain areas of Guizhou Province.
    ZHANG Wen-juan1,2, LIAO Hong-kai1, LONG Jian1**, LI Juan2, LIU Ling-fei1
    2014, 33(5):  1297-1303. 
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    To clarify the effects of landuse types on the turnover of soil organic carbon in Karst mountain areas, soil organic carbon content and its mineralization rates were measured in three soil layers (0-10, 10-20, and 20-30 cm) under shrub (SR), paddy (PD), dry land (DL), 3-year-old grassland converted from cropland (GCC-3), and 15-year-old grassland converted from cropland (GCC-15) in a typical demonstration area of desertification control experiment in southwestern Guizhou. The results showed that the contents of soil organic carbon in SR, PD, DL, GCC-3 and GCC-15 were 30.37, 31.24, 21.86, 17.49 and 22.50 g·kg-1, respectively. The contents of soil organic carbon in SR and PD were significantly higher than in DL, GCC-3, and GCC-15 (P<0.05). The mineralization rate of soil organic carbon was higher at the early stage, and lowered at the later stage. There were differences in the mineralization rate of soil organic carbon among the different land-use types. The mineralization rates of soil organic carbon in GCC-3 and GCC-15 were higher than under the other land-use types, and the mineralization rate of soil organic carbon in DL was higher than in PD. In the 0-10 and 10-20 cm layers, the longest halflife time of soil organic carbon was all found in SR, being 722 and 639 days in the corresponding layers, respectively. The content and half-life time of soil organic carbon in each of the three soil layers were greater in PD than in DL, GCC-3, and GCC-15, suggesting that PD could be one of the best land uses for long-term carbon sequestration in Karst mountain areas. In short, land use, especially returning cropland to grassland, was an important factor influencing soil organic carbon and its turnover rate in Karst mountain areas.
    Effects of reclaimed water irrigation on soil physicochemical properties and culturable microbial community.
    CHEN Dai-ci, WANG Ji-hua**, GUAN Jian-fei, XIA Lin, GONG Xue
    2014, 33(5):  1304-1311. 
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    The reuse of reclaimed water is a significant measure to solve the urban water crisis, but few studies have examined the effect of reclaimed water on the soil and soil microorganisms. Taking irrigation with tap water as the control, the effect of reclaimed water irrigation on soil physicochemical properties and microbial community diversity was studied by a variety of soil index measurement and microbial dilution separation. The results showed that the soil pH, soil moisture, organic matter (OM), total nitrogen (TN), total potassium (TK), available nitrogen (AN) and available phosphorus (AP) contents all showed a tendency of increase, especially TK, while the values of soil total phosphorus (TP), carbon/nitrogen (C/N) and available potassium (AK)  were lower under irrigation with reclaimed water than under the control treatment. A total of 62 strains of bacteria were separated from sampling sites, which belong to 20 species (genera). Bacillus was the dominant group in the soil irrigated with reclaimed water while Pseudomonas was dominant in the control treatment. Differences in the level of microbial diversity existed between the differently irrigated soils. Soil microbial evenness index (Jsw) and the probability of interspecific encounter (PIE) were higher, while Shannon index (H′), Pielou evenness index (Jsi), Margalef richness index (R1) and Patrick richness index (R2) were lower in the soil irrigated with reclaimed water. By correlation analysis, the close relationship among diversity index, richness index and evenness index reflected the consistency of microbial community characteristics. By hierarchical scaling analysis, the spatial pattern of the microbial community was described. The microbial community was separated into four clusters: reclaimed water-B (RW-B), reclaimed water-J (RW-J), reclaimed water-C (RW-C) and tap water (DW). RW-B, RW-J and RW-C were of the lowest similarity, while RW-B and RW-J shared the highest similarity. Canonical correspondence analysis between the microbial community of each site and environmental factors showed that microbial community structures were correlated with OM, TN and TP (P<0.05). TP had a great impact on Xanthomonas, Cellulomonas, Listeria murrayi and Corynebacterium fascians.
    Characteristics of soil nutrients and heavy metal pollution in wetlands under different land use patterns in Longwo Lake of Wuhu City, Anhui Province, China.
    YANG Yan-fang1, SHAO Ting1, LU Meng-yu1, SUN Shu-yun1, ZHANG Jing-yu1, ZHANG Ping-jiu2**
    2014, 33(5):  1312-1318. 
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    Soil nutrient and heavy metal contents in wetlands under different land-use patterns were analyzed and the index of soil heavy metal pollution and the potential ecological risk index were calculated to assess the effects of landuse patterns on soil ecology and environment in Longwo Lake of Wuhu City. The results showed that landuse patterns had significant effects on soil nutrient and heavy metal contents in the wetlands. In general, soil nutrient and heavy metal contents in net fishery wetland (NFW), pond fishery wetland (PFW), rubbish dumping wetland (RDW) and ditch wetland (DW) were significantly higher than in farming wetland (FW) and lake wetland (LW). All wetlands were seriously or very seriously polluted with Cd and moderately polluted with Cu, while NFW, PFW, DW, RDW, and DW were moderately polluted with Pb and Zn. Only soil Cd contents in NFW, PFW, and RDW seriously exceeded the second level of soil quality standard in China (GB 15618-1995). Integrated pollution indexes indicated that RDW, NFW, and PFW were exposed to serious heavy metal pollution and DW, FW, and LW were exposed to moderate heavy metal pollution. Integrated potential ecological risk indexes indicated that RDW, NFW, and PFW had a very serious potential ecological risk and DW, FW, and LW had a serious potential ecological risk, mainly due to the high potential ecological risk of Cd with contribution of 88.6%-96.2%. Fishery and rubbish dumping were the main sources of soil nutrient and heavy metal pollution. Soil nutrient and heavy metal pollution had a coupling relationship in the studied region.
    Effects of elevated CO2 on the rice quality of Japonica rice in copper and cadmium contaminated soil.
    WANG Xiao1,2, SONG Zheng-guo1**, WU Hui-bin1, LIAN Fei1, ZOU Hong-tao2
    2014, 33(5):  1319-1326. 
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    A pot experiment in open top chambers was conducted to investigate the effect of elevated CO2 on the uptake of Cu and Cd by five Japonica rice varieties (Qianchonglang-2, Shennong-9903, Yongfengjinsui, Fuhe-77, and Yuanfeng-6) in a soil contaminated with two levels of Cu and Cd. The results showed that under elevated CO2, Cu uptake by the rice varieties except Qianchonglang-2 in the lowly and highly-contaminated soils decreased by 20.6%-30.2% and 2.4%-12.3%, while Cd uptake increased markedly except Yuanfeng6 by 3.7%-297.4% and 31.7%-209.1%, respectively. Although the uptake of Cd by Yuanfeng6 decreased in the highlycontaminated soil, its Cd content still exceeded the China’s national hygienic limit for foods (Cd≤0.2 mg·kg-1). Additionally, elevated CO2 increased the values of target hazard quotients (THQ) for Cd toxicity to rice with the THQ >1 in Yongfengjinsui and Yuanfeng-6, which implied that elevated CO2 would increase the Cd risk of rice to human body health in contaminated soils.
     
    Characteristics of pollutants in urban rainfall runoff in Shenyang City.
    LI Chun-lin1,2, LIU Miao1**, HU Yuan-man1, BU Ren-cang1, SUN Feng-yun1,2, GONG Ji-ping1,2, CHEN Tan1,2
    2014, 33(5):  1327-1336. 
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    Rainfall runoff, the main driving force of pollutant migration, is the hotspot of urban nonpoint source pollution researches. Shenyang, a typical city of northeast China, was chosen as a case study. Discharge characteristics of ten main pollutants (TSS, TN, TP, COD, Cd, Pb, Cr, Cu, Ni and Zn) were analyzed in different underlying surfaces, including slope roof runoff, flat roof runoff and road runoff. The study demonstrated that pollutant concentration peaks were earlier than runoff peaks. The pollution level was more serious in the road runoff than in the roof runoff. TN was the main pollutant in the roof runoff. However, TSS, TN, TP, Pb and Cr were main pollutants of the road runoff. The concentrations of all pollutants exceed the V level of China’s national surface water quality standards. There was a correlation between TSS and other 8 pollutants in the runoff except TN. Nutrition elements (nitrogen and phosphorus) had strong positive correlations with precipitation and rainfall intensity. COD discharged gradually along with the duration of rainfall. Comparing the research with other countries or cities, we found that the pollution of TSS, TN, TP and COD in Shenyang roof runoff was lighter; however, there was heavy metal pollution. The concentrations of TSS, TP and some heavy metal pollutions (Pb, Cr, Cu and Zn) in the road runoff were very high, but the TN and COD concentrations were low.
     
    Establishment of ecological network based on landscape ecology in Anshan.
    ZHANG Lei1, SU Li1, WANG Jing-kuan1**, CHENG Ming2
    2014, 33(5):  1337-1343. 
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    Due to urbanization, habitat patches have become increasingly fragmented and the connectivity among them is gradually reducing. Changes in land use around these large patches seriously threaten regional environment. Ecological network building could provide an important function for the ecological environment. In this paper, ecological function nodes were selected to protect biodiversity, cultural construction and so on, according to the actual situation in Anshan, Liaoning Province. We comprehensively evaluated the impact of different landscapes’ structure and function on ecological function flow by the entropy weight method. Based on GIS, potential corridors were simulated by using the leastcost model. Ecological networks were built and analyzed based on the gravity model and network indices. Results show that the minimum path ecological network has the highest connectivity and highest closure. The higher connectivity and closure the ecological network has, the more favorable it is to the matter cycle and energy flux. The annular ecological network’s corridors are selected based on the importance of the corridors and its cost is moderate. Therefore, the annular ecological network is the core framework of ecological networks, based on the principles of ecology and economics. With the gradual improvement of economic and human environment requirements, it is appropriate to increase the number of corridors to build the minimum path ecological network which could improve connections between habitat patches and enhance the ability of sustainable development. This study can provide a scientific basis for the ecological landscape construction in Anshan.
     
    Analysis on the ecological risk in western Jilin Province based on landscape adjacency characteristics.
    LI Xiao-yan**, ZHANG Jing
    2014, 33(5):  1344-1350. 
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    Based on the remote sensing image data of the western Jilin Province during 1986-2008, this study extracted the landscape information using the GIS software, computed the spatial adjacency characteristics between the main landscapes and the obstacle landscape types, constructed the risk indexes of the western Jilin Province, and assessed the ecological risk based on the landscape pattern. The desertification showed more impact on arable land than on the others and the effect was also obvious in the analysis of the adjacency to the salinealkali land. In the past 20 years, the adjacency indexes of length, area and patch number of forest and grassland to the sand land decreased while that of arable land increased. From 1986 to 2008, the arable land was seriously threatened by desertification and salinization. The stress caused by desertification and salinization increased and the stress caused by salinization was more serious than that by desertification. Our results indicate that salinization becomes a threatening factor on the regional ecological environment sustainability.
     
    Spatial and temporal distribution patterns of wildfires in China based on MODIS data.
    JIAO Lin-lin1,2, CHANG Yu1**, HU Yuan-man1, WANG Xiao-li1,2
    2014, 33(5):  1351-1358. 
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    Wildfire is an important disturbance factor in natural ecosystems, posing great threats to people’s lives and properties while maintaining natural ecosystem diversity. Studying the spatial and temporal patterns of wildfires will help to understand the patterns of wildfire occurrence and thus provide the scientific basis for wildfire management. In this study, the spatial and temporal patterns of wildfires in China were analyzed using statistical software, SPSS, and GIS and remote sensing technology based on Terra/MOD14A2 data from 2006 to 2012. The results showed that the annual burned area tended to decrease generally although varied significantly among different years. The provinces greatly contributing to the change of the annual burned area were mainly from southern China, southwest and northwest regions. The monthly burned area had significant differences among various months and the most burned area occurred in March. The provinces greatly contributing to the change of the monthly burned area were from southern, southwest, northeast and northwest regions. Wildfires and environmental factors were closely related; wildfires easily occurred in hilly areas, in areas with average rainfall between 400 mm and 800 mm and average temperature between 0 ℃ and 10 ℃, and in coniferous forests. This study could provide a scientific basis for zoning wildfire risks and wildfire management in China.
    Spatial distribution characteristics and accessibility of national wetland parks in China.
    PAN Jing-hu**, ZHANG Jian-hui
    2014, 33(5):  1359-1367. 
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    By using GIS and the methods of nearest neighbor index, Ripley’s K function, and kernel density estimation, the spatial distribution of 298 China’s national wetland parks was analyzed. Based on the matrix raster data, the spatial accessibility of China’s national wetland parks at countylevel was calculated by using the cost weighted distance method and ArcGIS as platforms. The spatial differences of countylevel accessibility of the national wetland parks were analyzed by the exploratory spatial data analysis (ESDA). Results show that the national wetland parks generally exhibit an aggregated distribution. There is quite difference of spatial distribution of national wetland parks among both interprovinces and intereconomic regions. The average accessibility is about 144.07 min, and the area with the accessibility of national wetland parks within 120 min reaches 60%, while the area with the accessibility within 30 min accounts for 13.29%, and the longest time needs 1283 min for one park located at central Tibetan Plateau. Moreover, the distribution of the accessibility coincides with that of traffic lines. At county level, the estimated value of Moran’s I is positive. National wetland parks and adjacent areas show a strong positive correlation. The distribution of hot spots regarding the accessibility shows an obvious hot spots-sub-hot spots-sub-cold spots-cold spots distribution pattern from east to west. Service range of each national wetland park is more advanced in western regions than that in eastern and central China.
    Risk assessments of late rice flood disaster in South China.
    DUAN Hai-lai**, WANG Chun-lin, TANG Li-sheng, CHNE Hui-hua
    2014, 33(5):  1368-1373. 
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    Based on the late rice flood disaster risk assessment model, this article evaluates and predicts the late rice flood disaster risk degree in its production and growth period, as well as its temporal and spatial differences.  The distribution of the late rice flood disaster risk degree decreases generally from southeast to northwest in South China, that is, the highest in the southeast coast region, moderate in the central part, and the lowest in the northern Guangxi Province. The risk degree in southeast coast of South China area is 1.4-2 times of that in north of Guangxi Province.  From the changes of the flood disaster risk at different growth periods, influenced by the increase in the intensity of tropical cyclone precipitation during last flood season in South China area, the effects of precipitationinduced disaster are increasing during the period from sowing to jointing stage; but the effects of precipitation on the period from jointing to mature stage are contrary to that on the period from sowing to jointing stage. In recent 30 years, the flood disaster risk degree of late rice has a gradually decreasing trend in South China overall. Meanwhile, abrupt changes of the risk degree appeared obviously at the end of the 1990s, and thereafter, the risk degree decreases most significantly at a rate of 0.277 10 a-1.  The change rate of the late rice flood disaster risk degree is significantly regional and transitional. There is an increasing trend in southeast coast of South China, especially in the Pearl River Delta Plain and Chaoshan Plain, and the increasing rate is more than 0.10 10 a-1, while there is a decreasing trend in the inland mountain of South China where the descending rate is more than 0.05 10 a-1. The main reason for such changes is the topographic transitional belt. Therefore, the key periods of the late rice flood disaster risk in South China are from sowing to jointing stage, and the most attentions should be paid on the southeast coast region.
    Spatiotemporal variation of leaf area index in Beijing based on MODIS data.
    XIE Jun-fei1,2**, XU Rui2
    2014, 33(5):  1374-1380. 
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    In this paper, the monthly spatial dynamics of vegetation LAI during 2010-2012 in Beijing, China, were estimated based on the MODISLAI data and the functional classification of vegetation. The yearly dynamics and differences of vegetation LAI of various vegetations were also investigated based on Geographic Information System and Timesat software. The results suggested that the higher values of monthly vegetation LAI during 2010-2012 mainly occurred in the forest zones of the northwest and northeast mountains as well as the northern areas of Huairou District. The spatially descended trend was found from the northeast mountains to southwest area and then to the central Beijing City. Additionally, the changes of annual average LAI of various vegetations were not obvious during the study period. The annual average of LAI varied in the ranges of 1.45-1.50, 1.24-1.27, 0.90-0.92, and 0.48-0.51 for coniferous forest, broadleaf forest, grassland, and crop, respectively. The results of SavitzkyGolay filtering indicated that the growth trajectories of coniferous forest, broadleaf forest, grass, and crop could be reflected by the inter-monthly variation of LAI.
     
    Current situation and prospect of rice water-saving irrigation technology in China.
    YAO Lin1,2,3, ZHENG Hua-bin2,3,4, LIU Jian-xia1,2,3, HE Hui1,2,3, HUANG Huang2,3,4**
    2014, 33(5):  1381-1387. 
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    Irrational irrigation patterns of paddy field in China have caused severe water resource squander and low water use efficiencies, aggravated the shortage and pollution of water resources. Rice cropping in China, accounted for approximately 50% of total national water consumption. Therefore, to reduce water consumption and improve China’s rice water use efficiency will help ease China’s water shortage and water pollution. At present, there are four major water-saving irrigation technologies in China, including “shallowwetsun” irrigation, intermittent submerged irrigation, controlled irrigation, and rainfall collection. This paper systematically summarized the four water-saving irrigation technologies, illuminated water-saving and yield-increasing mechanisms of these technologies, and analyzed the effect of watersaving irrigation technologies on rice growth and development and the paddy ecological environment. However, these four water-saving irrigation techniques have some limitations: there are no technologies (measures) of cultivation and high-tech matching with them; water-saving effects are not very ideal; long-term applications of some efficient water-saving technology may reduce soil fertility. Consequently, to find out new water-saving irrigation techniques will become an inevitable choice for rice water-saving technology development in the future.
     
    Advances in simulation of reed wetland evapotranspiration based on multiple time and space scales.
    YU Wen-ying, JI Rui-peng, FENG Rui, WU Jin-wen, ZHAO Xian-li, ZHANG Yu-shu**
    2014, 33(5):  1388-1394. 
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    Wetland evapotranspiration is the major way of wetland water loss. It has attracted widespread attention because of its high sensitivity and important effect on climate change. Wetland evapotranspiration process can be divided into multiple scales including leaf, plant, canopy, landscape, region, etc. How to realize the coupling of processes and parameters at different time and space scales is one of the emphases and difficulties in wetland evapotranspiration research. This paper reviews the development of evapotranspiration simulation on wetland. The monitoring and simulation methods of reed wetland evapotranspiration are summarized from different time scales (such as daily, monthly, yearly) and different spatial scales (such as leaf, plant, canopy, region). The key technologies about how to expand different time and space scales are also summarized, and then the major research in future is discussed. Coupling parameters in atmospherevegetationsoil interface is the key to accurately simulate the evapotranspiration at different time and space scales in reed wetland. At present, there are few researches on the reed wetland evapotranspiration parameterization at different scales. Therefore, to explore the methods of evapotranspiration modeling and parameterization can provide theoretical supports for the choice of evapotranspiration assessment models of reed wetland.
     
    Effects of biochar application on soil properties and greenhouse gas emission.
    MA Xiu-zhi1**, LI Chang-sheng2, REN Le3, WANG Peng-fei2
    2014, 33(5):  1395-1403. 
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    Biochar is a charcoal produced under high temperatures using crop residues, animal manure, or any type of organic material. Biochar has multiple potential environmental benefits, foremost the potential to sequester carbon in soil for hundreds to thousands of years, which consequently can slow down the greenhouse effect so as to restrict global warming. Crop yields can increase as a result of applying biochar as a soil amendment. Moreover, greenhouse gas emissions are reduced significantly with biochar application to crop fields. However, obstacles exist that may stall rapid adoption of biochar production systems, including technology costs, feedstock availability, and the uncertainty of longterm effect of biochar application. Some characteristics of biochar depend on the biomass source and temperature, duration and method of pyrolysis. The effects of biochar on soil physical, chemical, microbial properties and emissions of greenhouse gases (such as carbon dioxide, methane and nitrous oxide) were reviewed. We also summarized the effects of biochar on rice production and greenhouse gas emissions in southern China and other foreign areas, and the characteristics of charcoal produced in forest fire and its environmental effects.
    Body-color polymorphism and its ecological and evolutionary function in aphids.
    LI Jin-bu1,2, FANG Li-ping2, MENG Ling1, LI Bao-ping1**
    2014, 33(5):  1404-1412. 
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    Body-color polymorphism is a widespread phenomenon in aphids, which offers an ideal model system for investigating the adaptive mechanisms and ecological evolutionary functions for  insect species. Although aphid bodycolor polymorphism has been recognized for nearly two centuries, the basic mechanisms are still unknown. In the present paper, we summarized the research progress in aphid body-color patterns, body-color pigments, the important factors affecting bodycolor, ecological and evolutionary functions of color polymorphism and its maintenance mechanisms. The aim is to provide new insights into further research about aphid color polymorphisms with regard to mechanisms of divergence and maintenance of body-color as well as its adaptive functions in evolutionary ecology.
    Construction of the EWE model of Futian mangrove wetland ecosystem.
    CHOU Qing-chuan1, XU Hua-lin2, LIU Jun3, SHI Xiu-hua4**
    2014, 33(5):  1413-1419. 
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    In the present study, the biological composition of Futian mangrove wetland ecosystem was divided into 15 functional groups and covers almost the whole process of energy flow in the ecosystem, including mangrove plants, zoobenthos, phytoplankton, zooplankton, birds and detritus. Ecopath with Ecosim (EWE) software was used to construct the EWE model of the Futian mangrove wetland ecosystem. Furthermore, we also analyzed the state, characteristics and nutritional relationships among different species, and evaluated the current health state of the mangrove wetland ecosystem. The analysis showed that detritus was the most important source of energy flow of Futian mangrove wetland ecosystem. Energy flow occurred mainly at the trophic levels Ⅰ→Ⅳ. The highest conversion efficiency occurred between the trophic levels Ⅰ and Ⅱ (28.8%), and the overall conversion efficiency was 11.2%, which is in line with the flow efficiency value (about 10%) quantified by Lindemann. The system took the most abundant advantage of the trophic level Ⅱ. The functional groups at the lower trophic levels played a key role in the process of energy transfer, and their impacts on the whole system were very strong. The ecosystem overall characteristic parameters-total biomass/total through (TB/TT), connectance index (CI) and system omnivory index (SOI)- were 0.163, 0.123 and 0.018, respectively. Therefore, it could be concluded that Futian mangrove wetland ecosystem is currently in a trend of degradation.
    Difference of measured sap flows of Bambusa chungii using thermal dissipation probes at different lengths and their in situ validation.
    ZHAO Ping**, MEI Ting-ting, ZHU Li-wei, NIU Jun-feng, NI Guang-yan
    2014, 33(5):  1420-1428. 
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    Thin bamboo wall may easily be penetrated through when installing the common type TDP sensor of 20 mm long for sap flow measurement. Differing with the case of thermal conduction in wood, the part of the upper probe penetrating into the bamboo cavity dissipates heat in a way of radiation. Hence, the dissipation, together with those unevenly distributed waterconducting units within the bamboo wall, may result in measurement inaccuracy of sap flux density and shorter probes have been recommended in general. However, lacking of in situ validation of shorter probes limits their applications for accurate sap flow measurements. In this study, sap flow of Bambusa chungii was simultaneously monitored using selfmade 5, 8 and 10 mm long TDPs in the field for testing their applicability as well as providing technical supports after theoretical analyses. Experimental results indicated that the difference between the fitted equation for calculating sap flux density that was established for B. chungii and the empirical one that was originally proposed by Granier was mainly due to the significant deviation of the parameter α. Such a discrepancy may be preliminarily resulted from the heat accumulating effect in the bamboo cavity that causes higher temperature in the area around the upper probe as well as the lower thermal diffusion coefficient (h0) of bamboo wall that, with a low water content, may also hoard heat and thus generate larger temperature difference between upper and lower probes. In addition, the way to insert probes into the bamboo wall also affected the measurement and might be another important factor leading to significant variation in monitored sap flux density of B. chungii even with TDPs at the same length. Further analyses on h0 of surrounding media of TDP provided reasonable explanation for these discrepancies.