Table of Content

08 July 2011, Volume 30 Issue 07

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Articles

Host selection and offspring developmental performances of Meteorus pulchricornis on Spodoptera litura larval instars.

2011, 30(07):  1317-1321. 

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A dual-choice experiment was conducted to observe the host selection and offspring developmental performances of koinobiontic parasitoid Meteorus pulchricornis on Spodoptera litura larval instars (except the first and last instars). The parasitoid showed no preference for L₄ and L₅, but exhibited preference to lower instar larvae in L₂ vs. L₃ and L₃ vs. L₄ . No significant difference was observed in the cocoon formation rate among the offspring parasitoids from different host instars at oviposition. The emergence rate decreased with the increase of host instars, and was higher from attacking L₂ and L₃ than that from attacking L₅. The mortality rate of the offspring developed from attacking L₅ was 2.5 times higher than that from attacking L₂ 2, and 5.4 times higher than that from attacking L₃. The offspring developed from attacking L₃ had the shortest development time (11.9 days), being 6.8 days shorter than that from attacking  L₄ and 4.7 days shorter than that from attacking L₂. There were no significant differences in the body size of progeny parasitoids on host instars at oviposition, as measured by hind tibia length. This study suggested that M. pulchricornis based its host selection more on host body size or its related characters than on host development stage per se.

Host-density patches selection and optimal foraging behavior of Meteorus pulchricornis(Hymenoptera: Braconidae).

2011, 30(07):  1322-1326. 

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A large transparent cage trial was conducted to observe the host selection of parasitoid Meteorus pulchricornis and its residence time on different host-density patches of Spodoptera exugia larvae, and the Cox proportional hazard model was used to examine the effects of host density, oviposition, and foraging attributes on the patch-residence time. The parasitoid made more choices of and undertook more visits to higher-density patches to realize higher parasitism rate. The residence time on the patches increased with host density. Cox model fitting results indicated that both the host density and the number of oviposition during the observation period had negative effects on the patch-leaving tendency, while the interaction of the two factors produced positive effects on the patch-leaving tendency, which could warrant the parasitoids to optimally exploit host patches to gain maximum fitness.

Flight capability and field dispersal behavior of Meteorus pulchricornis (Hymenoptera: Braconidae).

2011, 30(07):  1327-1331. 

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To gain insight into the foraging behavior of Meteorus pulchricornis in field, the potential flight capability of M. pulchricornis was measured on a flight mill, and two field releases were conducted in soybean field to measure the parasitism as affected by the release direction, time, and distance through the recapture and collection of Spodoptera litura larva hosts. The flight mill test showed that the number of taking-off was 14.48±0.82, total flight distance was 1283.00 m±45.60 m, overall flight duration was 2374.79 s±89.91 s, flight velocity was 0.54 m·s^-1±0.004 m·s^-1, and the longest single flight duration was 475.21 s±76.97 s. Field release trial indicated that release direction did not affect the parasitism significantly at the wind speed ≤4.2 m·s^-1, but the parasitism varied significantly with release time and distance. The parasitism decreased with the increase of the time elapsed and  the distance away from the release point. The parasitoid could disperse 36 meters away in one day. Based on these results, the characteristics of the foraging behavior of M. pulchricornis in field were discussed.

Mating choice among Ophraella communa geographical populations and their offspring developmental performances.

2011, 30(07):  1332-1336. 

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To assess the differentiation among the geographical populations of exotic leaf beetle Ophraella communa in China, a laboratory experiment was conducted to observe the assortative mating among the O. communa populations from Nanjing (32°N, 118.7°E), Changsha (28° N, 112.9°E), and Fuzhou (26°N, 119.3°E) and the offspring developmental parameters. The mating choice trial showed that in the six hours of observation, the probability of mating for the individuals of O. communa population from Nanjing with those from Fuzhou was significantly lower than that for the individuals within the population from Nanjing, but no significant differences were observed for the individuals between the populations from Nanjing and Changsha and within the population from Nanjing. When given choice between the females from different populations, the males of the populations from Nanjing and Fuzhou made more mating choice for the females from their own populations, but the males of the populations from Nanjing and Changsha exercised the same mating choice for the females from their own and other populations. The offspring from the mating among populations did not show any significant differences in egg hatching, pupation, and adult emergence rates. This study suggested that definite degree pre-mating isolation occurred between the O. communa populations from Nanjing and Fuzhou.

Host choice and leaf consumption of Ophraella communa (Coleoptera: Chrysomelidae) on Ambrosia artemisiifolia and Xanthium sibiricum.

2011, 30(07):  1337-1341. 

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To study whether Ophraella communa has host specialization on Ambrosia artemisiifolia and Xanthium sibiricum, a dual-choice trial was conducted to study the host selection of the O. communa originated from A. artemisiifolia (ragweed cohort) and X. sibiricum (cocklebur cohort), with the leaf consumption of the two cohorts on five relative plants X. sibiricum, A. trifida, Helianthus annuus, H. tuberosus, and A. artemisiifolia measured. The ragweed cohort O.communa showed a significant preference for A. artemisiifoliaover X. sibiricum, while the cocklebur cohort O. communa showed a significant preference to X.sibiricum over A. artemisiifolia, as manifested by the relative over-preferences. The leaf consumption by the two cohorts differed significantly on sunflower, but had no significant differences on the other test plants. Ragweed cohort showed a significant preference to A. artemisiifolia over the other test plants, with a consumption of leaf discs by 51.27 mm² in 24 hours, but showed less difference in the preference to other test plants, with the consumption of leaf discs by <40 mm². The leaf discs consumption of A. artemisiifolia by cocklebur cohort was 52.24 mm², not different from the consumption of sunflower and A. trifida but greater than that of X. sibiricum and H. tuberosus, and no significant difference between the latter two plants. It was suggested that X. sibiricum could be a suboptimal host plant as an alternative to optimal A. artemisiifolia for the leaf beetle O. communa.

Seasonal dynamics of spider diversity and rice planthopper abundance in organic farming paddy rice-duck field.

2011, 30(07):  1342-1346. 

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To explore the approaches and methods of insect pest management in organic farming paddy fields, a two-year investigation was conducted on the quanti
tative dynamics of spiders and rice planthoppers in organic farming middle-late rice-duck field in East China across rice growth season, with the conventional paddy fields (Ⅰand Ⅱ, according to the pesticide application rate) as the control. A total of 9-10 families of spiders were recorded for different farming systems. The spider’s species diversity as measured by Shannon index was in the order of conventional paddy field Ⅱ> conventional paddy field Ⅰ > organic farming rice-duck field, while the dominance index was the highest in organic farming rice-duck field. The spider’s abundance in early growth season was lower in organic farming rice-duck field than in conventional paddy fields Ⅰand Ⅱ, while that in middle and late growth seasons was in reverse. Rice planthopper’s abundance in organic farming rice-duck field had a greater seasonal fluctuation, compared with that in conventional paddy fields. The abundance of rice planthoppers was greater in organic farming rice-duck field than in conventional paddy fields, but the abundance of spiders had less difference, resulting in a lower spider/rice planthopper ratio in organic farming rice-duck field than in conventional paddy fields across rice growth season. The results suggest that the pest control in organic farming rice-duck field confronts serious challenge, and it is necessary to explore practical and feasible ecology-based management methods.

Arthropod diversity on  plants at field margins of organic farming paddy rice.

2011, 30(07):  1347-1353. 

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An investigation was conducted on the arthropod community on the plants (weeds, soybean, and sesame) at the margins of both organic farming paddy rice-duck field and conventional paddy field with wheat-rice rotation in East China across rice growth season. A total of 172 arthropod species belonging to 76 families, 12 orders, and 2 classes were collected, including 103 species of natural enemies (33 spiders, 6 predatory insects, and 64 parasitoid species) and 64 species of phytophagous insects. At the margins of organic farming paddy rice-duck field, the species richness and abundance of the spiders and insect natural enemies on the plants were >4.5 times and >1.5 times greater than those at the margins of conventional paddy field, respectively. The insect species richness at the margins of organic farming paddy rice-duck field was the highest on soybean and weeds (71), followed by on sesame (62), and the Shannon index was the highest on weeds; while at conventional paddy field margins, the insects on soybean had the highest richness (52) and Shannon index, and those on weeds had the smallest Shannon index. An obvious link was observed in the seasonal variations of the abundance between spiders and rice planthoppers on the weeds at organic farming paddy rice-duck field margins, but not observed at conventional paddy field margins probably due to the application of pesticides for the control of rice planthoppers. This investigation indicated that, compared with conventional paddy field, organic farming paddy rice-duck field was more beneficial to the protection of natural enemies, and planting soybean and sesame at conventional paddy field margins had positive effects on the conservation of arthropod community in paddy field.

Structure and diversity of major predatory natural enemies in  rice-duck integrated farming system.

2011, 30(07):  1354-1360. 

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A field plot experiment was conducted to study the community structure and species diversity of major predatory natural enemies in a  rice-duck integrated farming system across rice growth season. Three treatments were installed, i.e., rice-duck farming, conventional rice farming, and the control. The dominant species of major predatory natural enemies in the three treatments were all of Araneidae, Erigonidae, Lycosldae and Tetragnathidae, and the dominance indices of Araneidae, Erigonidae and Lycosldae in the rice-duck farming were higher than those in the other two treatments. In rice growth season, the total number of the major predatory natural enemies in the rice-duck farming and conventional rice farming was 14.9% and 1.7% lower than that in the control, respectively, and except in individual observation periods, the diversity index of the main predatory arthropods in the rice-duck farming was lower than those in the other two treatments. The decline of the diversity index of predatory natural enemies was more noticeable at the early stage of introducing ducklings into the experimental plot of the rice-duck farming. With the growth of rice, the diversity index of major predatory natural enemies in the rice-duck farming showed a persistent increasing trend.

Spatial ecological niches of Nilaparvata lugens and its main predatory natural enemies in rice-duck integrated farming system.

2011, 30(07):  1361-1369. 

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Three treatments including chemical fertilization, rice-duck  farming, and no chemical pesticides/fertilizer application (control) were installed to study the spatial distribution patterns and ecological niches of Nilaparvata lugens and its main predatory natural enemies. In the plots of chemical fertilization, rice-duck  farming, and the control, Theridiidae, Clubionidae and Salticidae shared the highest niche width, respectively, with a value of over 0.80. The spatial niche breadth of N. lugens in the plots of rice-duck  farming was 0.83, being 5.0% and 5.9% lower than that in the control and chemical fertilization plots, respectively. Rice-duck  farming made the common spatial domain of N. lugens and its main natural enemies Tetragnathidae, Coccinellidae, Salticidae, and Staphylinid increased, affording more probability of their encounter and enhancing the control potentialities of these natural enemies on N. lugens  to a certain extent. However, the niche overlapped between N. lugens and natural enemies Lycosidae, Linyphiidae, and Clubionidae decreased, which weakened the control potentialities of these natural enemies. Rice-duck  farming also had definite effects on the occurrence position and spatial domain of main predatory natural enemies on rice plant. In sum, rice-duck  farming could have positive effects on the outbreak and trade-off of N. lugens via altering the spatial distribution patterns and ecological niche characteristics of N. lugens and its main predatory natural enemies.

Pollination insects and their flower-visiting behaviors on endangered plant Amygdalus pedunculata.

2011, 30(07):  1370-1374. 

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An investigation was conducted on the pollination insect species, their flower-visiting behaviors, and diurnal activity rhythm on endangered plant Amygdalus pedunculata. A total of 21 visiting insect species belonging to 5 orders, 17 families, and 19 genera were recorded, among which, 15 species belonging to 3 orders, 11 families, and 13 genera were pollination insects. Anthophora melanognatha, Bombus patagiatus, Bombylius major, Syrphus ribesii and Halictus rubicundus were the main pollination insects. Their diurnal activity rhythms had greater difference, and their activity’s peaks staggered each other. Among the main pollination insects, A. melanognatha had the characters of large body size, short residence time, and carrying large amount of pollen, being the most efficient pollination insect on A. pedunculata, and thereby, the study of its biology and pollination ecology should be strengthened in future.

Odonata fauna and its diversity in Jiangsu Province of China.

2011, 30(07):  1375-1381. 

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In 2005-2010, an investigation by the methods of static watching and net-catching was conducted on the dragonflies in the places nearby the water areas suitable for dragonfly growth in Jiangsu. The investigation was made in the spaces of 20 metres along the sampling lines, with the Odonata fauna and its diversity identified and calculated. A total of dragonfly 53 species were recorded, belonging to 35 genera and 11 families, among which, Palearctic-Oriental species were richer, owned 18 species and accounted for 33.96% of the total, while Palearctic species were comparatively poor, accounted for 9.43%. The diversity index was 3.108, evenness index was 0.782, and dominance index was 0.169. In Nanjing and Lianyungang, the richness, diversity, and evenness indices were the highest, and the dominance index was the lowest, possibly due to the habitats in the two areas having a higher diversity and more suitable for the dragonfly existence.

Simulation and prediction of potential distribution of Helicoverpa armigera in China under global warming.

2011, 30(07):  1382-1387. 

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By using DYMEX 3.0 program to construct a bioclimatic model and using ArcGIS to treat graphs, this paper simulated and predicted the potential areas fitting for Helicoverpa armigrea survival in China under present climatic and future global warming scenarios. Under present climatic scenario, the habitats highly fitting for H. armigrea survival in China would be located in central and south Henan, north Anhui and Hubei, south Jiangxi and Fujian, Hunan, Guangxi, Guangdong, juncture of Shanxi and Gansu (Tianshui), and juncture of Sichuan and Tibet (Batang), moderately fitting habitats would be the most areas along the Yellow and Yangtze rivers, and low fitting habitats would be mainly in the three provinces of Northeast China, and Xinjiang, Tibet, and Qinghai. Under future global warming scenario (a 3 ℃ increase of air temperature by the end of this century), the northern border of moderately fitting habitats would be shifted from a line of Yingkou, Beijing, Shijiazhuang, Taiyuan, Yan’an, Lanzhou, and Batang to a line of Shenyang, Hohhot, Jiuquan, Gomud and Lhasa, with the latitude shifted northward 3° and the elevation increased by 300-500 m, the current low fitting habitats in large areas of Xinjiang would become moderately fitting habitats, some highly fitting habitats such as Tianshui and Batang would expand, and some habitats in Northern and Southern China, Taiwan, Hong Kong, and Hainan would shrink. A discussion on the prediction results was made, based on the biological characteristics of H. armigrea.

Spatial distribution of white-backed planthopper (Sogatella furcifera) in Xiushan County of Chongqing, Southwest China based on GIS analysis.

2011, 30(07):  1388-1393. 

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Based on the 2003-2009 field survey data of white-backed planthopper Sogatella furcifera at its early immigration stage in Xiushan County of Chongqing, and by using geographical information system (GIS) and traditional spatial analysis methods, this paper studied the spatial distribution pattern and its dynamics of the planthopper in the county. In 2003-2009, the S. furcifera population within the county presented an obvious aggregated spatial distribution, and the inverse distance weighted interpolation figures showed that the aggregation center and distribution pattern differed in different years. Overall, S. furcifera population more aggregated in the middle area of the county, including Guanqiao, Guanzhuang, and Pingkai towns, with the aggregation center there in four of the seven years, but less aggregated in surrounding mountain areas, only with the aggregation center in the south of the county in 2007, in the east of the county in 2008, and in the north and west of the county in 2009.

Genetic variation of Dendrolimus spectabilis (Lepidoptera) geographical populations and its correlations with ecological factors.

2011, 30(07):  1394-1397. 

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By means of ISSR, this paper analyzed the molecular genetic variation of four Dendrolimus spectabilis populations collected from Taian (Culai Mountain), Qingdao (Jiaonan), Chaoyang (Lingyuan), and Huludao (Suizhong). Among the four D. spectabilis populations, the Huludao population had a higher genetic diversity. There existed definite genetic differentiation among the populations. Correlation analysis showed that the D. spectabilis populations genetic diversity was negatively correlated with elevation, positively correlated with mean annual air temperature and humidity, but less correlated with latitude. Besides, the genetic distance between the pairs of the populations was positively correlated with elevation distance.

Comparison of acaricidal bioactivity of natural and cultivated Artemisia annua leaves acetone extracts against Tetranychus cinnabrinus.

2011, 30(07):  1398-1402. 

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A laboratory test was conducted on the acaricidal bioactivity of natural and cultivated Artemisia annua leaves acetone extracts against Tetranychus cinnabarinus. The LC₅₀, 48 h of natural and cultivated A. annua leaves acetone extracts was 0.295 and 0.567 mg·ml^-1, respectively, i.e., the acetone extract of cultivated A. annua leaves had a higher acaricidal bioactivity. By column chromatography, a total of 19 and 17 fractions were isolated from the natural and cultivated A. annua leaves acetone extracts, respectively. At the concentration 2.5 mg·ml^-1, the 11th fraction of the extract of natural A. annua leaves and the 13th fraction of the extract of cultivated A. annua leaves could kill all test mites after treated for 48 h. The toxicity test showed that the LC₅₀, 48 h of the 11th fraction of the extract of natural A. annua leaves was 0.120 mg·ml^-1, and the LC₅₀,48 h of the10th, 12th, and 13th fractions of the extract of cultivated A. annua leaves was 0.144, 0.163, and 0.117 mg·ml^-1, respectively. This study suggested that the acaricidal activity of the acetone extract of cultivated A. annua leaves against T. cinnabarinus was superior to that of the natural A. annua leaves.

Feeding level of folivorous insects in forest canopy: Quantitative methods and research advances.

2011, 30(07):  1403-1410. 

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There is a great spatiotemporal variability in the feeding level of folivorous insects in forest canopy. This paper discussed the significance of quantitatively determining the feeding level of folivorous insects in forest canopy, introduced the related approaches, including sampling design and leaf area analysis, and analyzed the advantages and disadvantages of each of the approaches. Comments were given to the related researches in China. The research approaches for quantitatively estimating this feeding level were categorized as the approaches based on green leaf samples and those based on fallen leaf samples, and the sampling techniques were classified as canopy-based and ground-based. The approaches based on green leaf samples included destructive leaf sampling and in situ continuous observation; while those based on fallen leaf samples were to collect the fallen leaves within forest stand, measure the percentage of leaf area lost, and then, estimate the feeding level at forest stand scale. Three key research areas related to the feeding level of folivorous insects in forest canopy were proposed.

Germination strategies of Suaeda salsa at different temperature and under different salt stress.

2011, 30(07):  1411-1416. 

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Aimed to understand the germination strategies of Suaeda salsa under different environmental stress in the Yellow River Delta, an indoor germination test was conducted, and the seedling’s Na⁺ and K⁺ contents were determined at different temperature, salinity, and alkalinity, and in seawater solution. The thermal time and base temperature for the seed germination were 24.57 ℃·d and 0.62 ℃, respectively, and the optimal temperature was 20 ℃-35 ℃. The germination percentage was high at 5 ℃-40 ℃, and the germination rate increased significantly when the temperature increased from 5 ℃ to 35 ℃. The germination percentage was higher than 50% in 500 mmol·L^-1 of NaCl, and about 38% in 100% seawater. After seeds transferred from high concentration NaCl solutions to distilled water, the un-germinated seeds  could germinate well, which indicated that the un-germinated seeds could remain active in high salt habitats. With the increasing concentration of NaCl in solution, the seedling’s Na⁺ content increased significantly, while the K⁺ content had less change. In 200 and 300 mmol·L^-1 of NaHCO₃, the seedling’s Na⁺ and K⁺ contents were significantly lower than those in 100 mmol·L^-1 of NaHCO₃, indicating that high alkalinity stress affected the ion accumulation in S. salsa seedling’s significantly. With increasing seawater concentration, the seedling’s Na⁺ and K⁺ content also had significant increase. Therefore, the wide temperature-adaptation and high salt-tolerance for seed germination, the high seed vigor under high salt stress, and the high salt ion accumulation in seedling could be the main germination strategies of S. salsa adapting to the complicated environments in saline-alkaline wetlands of the Yellow River Delta.

Impacts of NaCl stress on Oligostachyum lubricum cell membrane permeability  and mineral ion uptake, transportation, and allocation.

2011, 30(07):  1417-1422. 

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A pot experiment was conducted to study the salt-adaptation mechanisms of Oligostachyum lubricum under different soil NaCl stress (0(CK), 1‰, 2‰, 3‰,
4‰, 5‰ and 6‰) for 45 days, with the parameters leaf abscission rate, leaf cell membrane permeability, and the uptake, transportation, and allocation of K⁺, Na⁺, Ca²⁺ and Cl^- in different organs investigated. Under 1‰-2‰ NaCl stress, the leaf abscission rate and ion leakage had no significant differences with the control; but under 3‰-6‰ NaCl stress, the leaf abscission rate and ion leakage increased significantly, and the damage increased with increasing soil NaCl concentration. Along with the increasing concentrations of Na⁺ and Cl^- in the organs of O. lubricum, the K⁺ concentration in root, culm, and branch decreased,  Ca²⁺ concentration in the three organs changed slightly, and the transportation ofK⁺ and  Ca²⁺ from root to culm and from culm to branch slowed down gradually. Due to the stronger selective absorption of K⁺ and  Ca²⁺ by leaf under 3‰-6‰ and 1‰-2‰ NaCl stress, respectively, the leaf K⁺ concentration increased rapidly with increasing soil NaCl stress while the leaf  Ca²⁺ concentration decreased after an initial increase, being of significance for keeping the ion homeostasis in leaf and maintaining the normal growth of seedlings. The significantly higher concentrations of Na⁺ and Cl^- in leaf than in other organs under 3‰-6‰ NaCl stress reduced the leaf osmotic potential, being conducive to the upward transportation of water, and also, could mitigate the salt toxicity on O. lubricum via leaf abscission.

Biological characteristics of Jatropha curcas root border cells and toxic effect of cadmium on the cell viability.

2011, 30(07):  1423-1428. 

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Jatropha curcas root border cells were detached from root tip and cultured by aeroponics to study their biological characteristics and the toxic effect of cadmium on their viability. Most of the cells were elliptical, and a few of them presented bend claval shape. The cells had the highest viability when the
root length was 15 mm, and their pectin methylesterase (PME) activity somewhat decreased with root elongation. Cadmium had obvious toxic effect on the cells. With the increasing concentration of cadmium and the increasing treating time, the viability of the border cells all showed a decreasing trend.

Litter standing biomass and water-holding characteristics in typical primary and secondary forests in karst region of northwest Guangxi.

2011, 30(07):  1429-1434. 

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Taking three typical primary forests wing-hackberry (Pteroceltis tatarinowii), Chinese Loropetal (Loropetalum chinensis),  Beautiful Sweetgum (Liquidambar formosana) and three typical secondary forests round-leaved tallow tree (Sapium rotundifolium), Chinese Alangium (Alangium chinense), and NegundoChaste-tree (Vitex negundo) in karst region of northwest Guanxi, Southwest China as test objects, a comparative study was conducted on the litter standing biomass, water-holding capacity, water-holding rate, and water-absorption rate. Among the test forests, Chinese Alangium had the largest dry litter standing biomass (3.3 t·hm^-2), followed by round-leaved tallow tree (3.2 t·hm^-2) and Beautiful Sweetgum (2.9 t·hm^-2), while wing-hackberry had the least one (1.8 t·hm^-2). The litter water-holding capacity in different type forests was in the order of Chinese Alangium > China Loropetal > Negundo Chaste-tree > round
-leaved tallow tree > Beautiful Sweetgum > wing-hackberry, and the litter potential water-holding rate in wing-hackberry, China Loropetal, Beautiful Sweetgum, round-leaved tallow tree, Chinese Alangium, and Negundo Chaste-tree forests was 301%, 342%, 224%, 253%, 288%, and 328%, respectively. The litter water-holding capacity and water-holding rate increased logarithmically with the increasing time of immersed in water. The litter water-absorption rate was the largest in China Loropetal forest, followed by in Negundo Chaste-tree, wing-hackberry, Chinese Alangium, and round-leaved tallow tree forests, and in Beautiful Sweetgum forest. The litter water-absorption rate decreased with time. To sum up, in karst region of northwest Guanxi, the litters in secondary forests had a larger water-holding capacity but smaller water-holding and water-absorption rates than primary forests, suggesting that the accumulation of litters in primary forests was of more eco-hydrological significance, compared with that in secondary forests.

Variation patterns of solar radiation above subtropical evergreen broadleaved forest and open area in Ailao Mountains.

2011, 30(07):  1435-1440. 

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Solar radiation is the primary source of energy for forest ecosystem. To explore the influence of subtropical evergreen forest on the distribution of solar radiation, a comparative study was made on the variation patterns of solar radiation above the forest canopy and open area in Ailao Mountains, based on the observation data of solar radiation from the Subtropical Forest Ecosystem  Station in Ailao Mountains. There existed differences in the annual variation of solar radiation above the forest canopy and open area due to the seasonal variation of vegetation. The ratio of effective radiation to global radiation and the albedo above the canopy was lower than that above the open area, but the ratio of net radiation to global radiation was in adverse, due to the influence of the canopy. Compared with those in other areas of China, the ratio of net radiation to global radiation above the forest canopy in Ailao Mountains was higher, while the albedo was lower. The glboal radiation in the Mountains was averagely 207.7 MJ·m^-2 and 357.5 MJ·m^-2 higher than that in the Dinghu Mountains and Heshan Mountains with the similar altitude and vegetation type as Ailao Mountains, respectively, suggesting that high global radiation looked very important for the subtropical evergreen forests at the altitude above 2200 m and under temperate cool moist condition.

Impacts of extreme drought in spring 2010 on karst vegetations in Shilin of Yunnan Province, China.

2011, 30(07):  1441-1448. 

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Studies on the impacts of extreme drought on karst plant communities are the basis for the management of degraded karst ecosystem. In order to underst
and the impacts of extreme drought event happened in Southwest China in spring 2010 on the karst vegetations, an investigation by the method of counting individual numbers of each plant species was conducted in May 2010 to analyze the structure of three natural karst plant communities (Cyclobalanopsis glaucoides forest, Quercus variabilis forest, and karst shrubs) and five artificially restored plant communities (Pinus yunnanensis forest, Alnus nepalensis forest on natural soil, A. nepalensis forest on covered new soil, Acacia dealbata forest, and Cupressus lusitanica forest) in the Shilin karst region of Yunnan. The feature of the extreme drought event was analyzed by the deviation indices of meteorological elements; the drought-suffered degree of the karst plant communities and species was analyzed by drought-suffering rate and mortality; and the impacts of the extreme drought on the karst plant cmmunities were evaluated by the biodiversity indices calculated with the dead and withered species number and individuals number, alive species number and individuals number, and alive but suffered species number and individuals number. This extreme drought event began in autumn 2009 and ended in June 2010, with the characteristics of long-lasting and deep level. The average mortality rate and drougt-suffering rate of the eight plant communities were 25.1% and 30.6%, respectively, and differed greatly with the plant communities. After the extreme drought, the naturally-restored plant communities still maintained their original species structure in regenerated layers, while the artificially restored plant communities had greater differences. The P. yunnanensis forest and the A. nepalensis forest on natural soil were less affected, the A. nepalensis forest on covered new soil and the A. dealbata forest basically lost their original species strucutre and size classs structure, and the C. lusitanica forest nearly had the original species strucutre and size classs structure, though half plants were dead. The extreme drought changed the stucutre and biodiversity of the plant communities to certain extent, and the drought-tolerance of artificially restored plant communities was weaker than that of natural plant communities. Therefore, appropriate plant species and restoration approaches should be chosen to restore the vegetations of degraded karst ecosystem.

Relations between plant species richness and community productivity of typical grasslands in Qinghai Lake basin.

2011, 30(07):  1449-1453. 

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The relationship between plant species diversity and primary productivity is a hot topic in biodiversity research. Based on the 2009-2010 observation data from the sampling sites in Qinghai Lake basin, this paper studied the relations between the plant species richness and community productivity of typical grasslands in the basin at different scales. At small scales (within and between plant communities), the relations were linear positive or negative, i.e., for alpine steppe and temperate steppe, the species richness increased with increasing productivity, but for swamp meadow and alpine meadow, the species richness decreased with increasing productivity. At large scale (whole basin), the relations were mainly in single-peak type. In the basin, the species richness was from 2 to 9, and the community productivity ranged in 65-585 g·m^-2·a^-1. Swamp meadow had the highest community productivity, followed by alpine meadow, alpine steppe, and temperate steppe.

Seasonal dynamics and strategies of soil seed banks in karst region of northwest Guizhou.

2011, 30(07):  1454-1460. 

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In this paper, 0-10 cm soil samples were collected four times (April, August and December of 2008, and May 2009) from five sites with plant communities at different succession stages in karst region of northwest Guizhou, and germinated in a greenhouse, aimed to understand the seasonal dynamics and strategies of the soil seed banks. In the soil seed banks, a total of 130 species were identified, and the seed density varied from 541 to 11180 ind·m^-2.Herbaceous plants seed density and species number were far greater than woody plants’, and sampling time and sites had significant effects on the mean values of the seed density and species number in the soil seed banks. At all five sites, the mean species number in the seed banks was the highest in April and the lowest in December, with an exception in grassland where the species number in soil seed bank was the lowest in August. The seed density peaked in April, and had no significant differences in August, December, and next May. The peaks of the seed density and species number in April could be due to the seed input/output pattern, which highly related to phenology, and to the persistence of seeds from previous years. Four seasonal soil seed bank strategies were identified, two transient and two persistent. Soil seed-bank strategy is a life-history trait of plant species, but the disturbance history and microenvironmental factors also have effects on the seasonal variations in seed quantity of some species.

Soil nitrification activity in typical sand-fixing plantations in Horqin Sandy Land.

2011, 30(07):  1461-1466. 

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Taking 26-year-old Caragana microphylla, Hedysarum fruticosum, Salix gordeivii, Artemisia halodendron, and Pinus sylvestris var. mongolica plantations and different aged C. microphylla plantations in Horqin Sandy Land as test objects, this paper measured the soil nutrient contents, enzyme activities, and nitrification activity. Among the five 26-year-old plantations, C. microphylia plantation had obviously higher soil organic matter, total N, NH₄⁺-N, and NO₃^--N contents and the highest soil urease, protease, and nitrification activities, and S. gordeivii plantation had the highest soil nitrate reductase activity. The soil urease and protease activities were significantly positively correlated with soil organic matter content. With the increasing age of C. microphylla plantation, the contents of soil organic matter, total N, NH₄⁺-N, and NO₃^--N, the activities of test soil enzymes, and the soil nitrification activity increased, and the soil urease and protease activities had significant positive correlations with the plantation age.

Historical records of sediment polycyclic aromatic hydrocarbons in Qinghai Lake, Northwest China.

2011, 30(07):  1467-1472. 

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By adopting GC/MS techniques, this paper analyzed the vertical distribution of 16 priority polycyclic aromatic hydrocarbons (PAHs) proposed by US EPA in a dated 0-20 cm sediment core from Qinghai Lake in Northwest China, and identified the possible sources of the PAHs. The total PAHs (sum of 16 the priority PAHs, TPAHs) concentration in the core ranged from 495.1 to 1172.5 ng·g^-1, and had an increasing trend from deeper layer to surface layer. The vertical profile of the sediment PAHs in Qinghai Lake was basically similar to that in the East China Sea and the Pearl River Estuary, but clearly different from that in developed countries. The sediment PAHs in Qinghai Lake were dominated by 2-3 rings PAHs (including naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, and anthracene), accounting for 72.4%±8.9% of TPAHs on an average. The sediment PAHs in Qinghai Lake were mainly originated from the long-distance atmospheric transport resulting from low temperature combustion of domestic coal and woods, but the PAHs from high temperature process (such as vehicle emission) had an obvious increasing trend in recent years.

Allelopathy of parsley seed extracts on Fusarium oxysporium f. sp. cucumeris.

2011, 30(07):  1473-1478. 

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By using distilled water, ethanol, and acetone as extraction agents, the parsley seed extracts were obtained to approach whether the extracts had allelopathy on Fusarium oxysporium f. sp. cucumeris and the intensity of the allelopathy with the help of growth rate method. All the three kinds of the extracts did have allelopathic effect on F. oxysporium f. sp. cucumeris, and the effect increased with increasing concentration of the extracts. After treated with the highest concentration 50 mg·ml^-1 of the extracts for 144 h, the growth rate of F. oxysporium f. sp. cucumeris was decreased by 31.1%, 49.6%, and 57.5% for the distilled water, ethanol, and acetone extracts, respectively, suggesting that ethanol and acetone extracts had stronger allelopathic effect than distilled water extract.

A high efficient carbendazim-degrading bacterial strain: Its isolation and identification.

2011, 30(07):  1479-1483. 

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By the method of continuous enrichment culture, a high efficient carbendazim-degrading bacterial strain XJ-H was isolated from the grape vineyard soil with a long-term application of carbendazim in Shihezi of Xinjiang, Northwest China. Through the Biolog analysis, 16S rDNA sequences comparison, and phylogenetic analysis, the XJ-H was identified as Azospirillum brasilense. The XJ-H could utilize carbendazim as the sole carbon or nitrogen source. After inoculated into the mineral salt medium containing 600 mg·L^-1 of carbendazim, the XJ-H could degrade 95.6% of carbendazim within 11 d, with an average degradation rate of 52.24 mg·L^-1·d^-1.

Toxic effects of trichlorfon on perch Lateolabrax maculatus.

2011, 30(07):  1484-1490. 

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In order to provide reference data for the disease control in Chinese perch (Lateolabrax maculatus) culture, this paper studied the acute toxicity of different concentration trichlorfon to the perch fry and juvenile. The GSH and MDA concentrations and SOD, CAT, GOT, GPT, and AChE activities in juvenile liver were determined, and the total dyskaryosis and micronuclear rates of juvenile erythrocytes were calculated. The LC₅₀ for the perch fry exposed to trichlorfon was 7.76 mg·L^-1 (24 h), 3.02 mg·L^-1 (48 h), 1.74 mg·L^-1 (72 h) and 1.58 mg·L^-1 (96 h), and the safe concentration was 0.14 mg·L^-1; while the LC₅₀ for the perch juvenile exposed to trichlorfon was 10.96 mg·L^-1 (24 h), 6.15 mg·L^-1 (48 h), 3.98 mg·L^-1 (72 h) and 2.89 mg·L^-1 (96 h), and the safe concentration was 0.58 mg·L^-1. Lytic necrosis was observed in the liver tissues of agonal individuals. After exposed to trichlorfon for 48 h, and with the increase of trichlorfon concentration, the juvenile liver’s GSH concentration decreased first, then recovered, and decreased again, MDA concentration increased first and recovered then, SOD activity had no significant difference with that of the control group, CAT activity decreased first and recovered then, GPT activity maintained at lower level, GOT activity of 1.35 and 2.70 mg·L^-1  trichlorfon groups decreased, and AChE activity had a slight increase after an initial decrease. The GSH and MDA concentrations and the CAT, GPT、GOT and AChE activities were sensitive, while the SOD activity was not sensitive to the trichlorfon stress. After exposed to 1.45 mg·L^-1 and 0.73 mg·L^-1 of trichlorfon for 96 h, the juvenile’s total erythrocyte dyskaryosis rate and micronuclear rate were significantly (P<0.05) higher than those of the control group respectively.

Heavy metals distribution and accumulation patterns in the tissues of two kinds marine gastropods in Pearl River  estuary.

2011, 30(07):  1491-1496. 

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Based on the measurements of Cu, Zn, Pb, Cd, and As concentrations in various tissues of Bursa rana and Turritella bacillum from the Pearl River Estuary, this paper studied the distribution and accumulation patterns of the heavy metals in the tissues of the two marine gastropods in the estuary. Our results revealed that hepatopancreas and intestine had greater differences in the enrichment patterns of the heavy metals, gills could play an important role in the enrichment of the heavy metals, and gonad was an important tissue for the enrichment of the residual heavy metals. Though the heavy metals concentrations in human body via eating the two gastropod species did not exceed the tolerable intake dose proposed by the Codex Alimentarius Commission, more attention should be paid to the potential risks of the co-toxicity of the heavy metals to human health.

Shell morphology of Corbicula fluminea (Müller, 1774) and its implication for the adaptation to environmental change in the major drainage basins of China.

2011, 30(07):  1497-1503. 

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The morphological change of bivalve mollusk is believed to be an adaptation to environmental change, but the adaptation mechanism under different environmental conditions may differ. Corbicula fluminea (Müller, 1774) is a benthic bivalve native to South and East Asia and a dominant invasive species in many aquatic environments globally. In this paper, specimens of  C. fluminea  were collected  along a transect crossing the major watersheds of China, including the Yellow, Huaihe, Hanshui, Yangtze, and Xijiang Rivers, with the morphometry studied, aimed to understand the regional change of  C.fluminea shell morphology and its affecting factors. In the upstream tributaries of the Yangtze and Xijiang Rivers, which were located in the mountainous regions of western China, the C. fluminea shell was relatively long, low, and thin; while in the lower reaches of Yellow river, upstream tributaries of Huai River and Hanshui River, and middle and lower reaches of Xijiang River, which were located in the hilly areas or plains in the south and east China, the shell was relatively short, high, and thick. These changes revealed the adaptation of the clam to the changes of water current rate. The large contrast of topography created high flow rate in mountainous regions, where the clam evolved to become longer, lower, and thinner so as to resist the involuntary displacement by high flow rate water current; while the slow flow rate in the plains or low mountain areas encouraged the shell morphology to become relatively short and round. The changes of water temperature and water chemistry (mainly Ca²⁺ and K⁺ concentrations) had little effects on the shell morphometry. These results not only provided insight into the adaptation mechanism of clams to environmental change, but also helped guiding the cultural practices of C. fluminea in China.

Relationships between land surface temperature and normalized difference vegetation index based on urban land use type.

2011, 30(07):  1504-1512. 

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Based on the QuickBird, Landsat/TM images, and GIS spatial analysis techniques, the urban land use information, land surface temperature (LST), and normalized difference vegetation index (NDVI) in Shenyang City were obtained, and the differences of and spatial relationships between the LST and NDVI for different urban land use types in the City were quantitatively analyzed. There was an obvious reverse variation trend between the LST and NDVI, and the mean LST and NDVI values differed significantly with land use type. Multiple comparisons showed that the mean LST and NDVI values of pairs of each land use type also had significant differences, and the correlation between LST and NDVI was significantly affected by the scale of spatial resolution, being increased first, decreased then, and increased again with increasing spatial scale. This study could provide scientific basis for mitigating urban heat island effect in urban planning and urban green space system planning.

Spatial distribution characteristics of vegetation phenology in northern Tibetan Plateau based on MODIS enhanced vegetation index.

2011, 30(07):  1513-1520. 

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In this paper, the 2001-2010 time-series TERRA/MODIS EVI dataset of northern Tibetan Plateau was reconstructed by asymmetric Guassian function fitting method, and the yearly key vegetation phenological parameters including the maximum EVI (EVI_max) in growth season, growth season length, green-up date, and wilting date of typical grassland plants in the region in 2001-2010 were extracted with dynamic threshold method. On these bases, the spatial distribution patterns of the vegetation phenology in northern Tibetan Plateau were analyzed. For the typical grassland plants in the region, their EVI_max in growth season, growth season length, and green-up date all showed the spatial distribution of horizontal transition from southeast to northwest and vertical zonation in southeastern Nagqu mountain topography, and the three phenological parameters all decreased in the order of mixed agriculture-forestry zone > forest and shrub > meadow > steppe > desert steppe. As for the wilting date, it was obviously later in mixed agriculture-forestry zone than in other vegetation cover types. Considering for different climatic zones, the EVI_max in growth season, growth season length, and green-up date all performed the order of sub-humid area > semi-arid zone > arid zone. Besides, with the increase of altitude, the EVI_max in growth season became smaller, growth season length became shorter, and green-up date postponed.

Expansion characteristics and its driving forces of built-up area in Tianjin based on remote sensing and GIS.

2011, 30(07):  1521-1528. 

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Spatiotemporal expansion of urban area is an important indicator for characterizing urbanization level. In this paper, the information of recent 20 years land use change in the six districts of Tianjin central urban area and four districts around the urban area was extracted by integrating four TM/ETM images from 1987 to 2006, and, combining with socio-economic statistic data and applying GIS spatial analyses and spatial gravity center transfer model, the expansion process, orientation, and driving forces of Tianjin built-up area were analyzed. In 2006, up to 82.0% of construction lands were in the central urban area of Tianjin, and near 24.9% were in the four districts around the urban area. From 1987 to 2006, the built-up area showed a large expansion, with the construction lands increased by 19.1%, and the period 2001-2006 was most evident in built-up area expansion. The increase of construction lands was dominantly from agricultural lands and water area. In recent 20 years, the expansion of Tianjin built-up area was mainly in an export-oriented way, with the six districts in central urban area as the center and an overall southeastward transfer of gravity center. Economic development, especially the rapid growth of GDP and the adjustment of industrial structure, was the most important factor controlling the expansion of the built-up area in recent 20 years. Transportation infrastructure improvement was the impetus for the built-up area expansion and partly affected the expansion orientation, population increase as a result of economy development also accelerated the expansion of the built-up area, and macroscopic policies, in a large degree, determined the expansion pattern and scale of Tianjin City.

Diurnal variation patterns of precipitation in Liaoning Province from May to September.

2011, 30(07):  1529-1534. 

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Based on the hourly precipitation data in May-September 1994-2008 from 52 meteorological stations in Liaoning Province, and by using four precipitation indices (hourly precipitation, hourly precipitation frequency, hourly precipitation intensity, and different duration precipitation), this paper analyzed the diurnal variation characteristics of precipitation in the Province from May to September. Both the precipitation and the precipitation frequency in the Province in May-September presented a diurnal pattern of bimodal distribution, with the peak periods at 14:00-17:00 and 2:00-8:00, and the precipitation intensity presented unimodal pattern, with the peak period at 14:00-17:00. The average correlation coefficient of precipitation and precipitation intensity was 0.8, while that of precipitation and precipitation frequency was 0.5, suggesting that the precipitation was closely related to precipitation intensity, and less affected by precipitation frequency. The precipitation and precipitation frequency of short-time precipitation events had greater contribution to the total precipitation and total precipitation frequency, compared with those of long-duration precipitation events, and the short-time precipitation events mainly took place at 14:00-19:00, while the long-duration precipitation events mainly appeared at 2:00-9:00.

Dynamic evolution of natural wetlands in Yellow River Delta and related driving factors.

2011, 30(07):  1535-1541. 

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Based on the 1989, 2000, and 2009 Landsat TM/ETM⁺ images of Yellow River Delta, and in combination with GIS approach and validation-on-spot, this paper analyzed the dynamic evolution and its driving factors of natural wetlands in the Delta. Under the effects of water and salinity, the spatial distribution of the natural wetlands presented a regular change pattern. The annual change gradient and dynamic degree of the natural wetlands area was -0.3 and 3.1 in 1989-2000, and -1.8 and 5.1 in 2000-2009, respectively, indicating an accelerated change of the natural wetland area in 2000-2009. Many factors affected this change, of which, the water regime of Yellow River was the main driving factor. There existed definite correlations between parts of the natural wetlands. Human factors such as the construction of culture pond and the reclamation for paddy field contributed to the reduction of natural wetlands. The increasing construction land was the main reason for the reduction of bush-grass lands.

Uncertainties in agricultural non-point source pollution simulation: Research progress.

2011, 30(07):  1542-1550. 

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With the improvement of the standards in point-source pollution control, the issues of non-point source (NPS) pollution become increasingly prominent. Agricultural NPS pollution, due to its wide coverage, difficulty to control, and large amounts of uncertainties in simulation, has become a hot spot in recent studies of water environment pollution control. Aiming at the uncertainties in agricultural NPS pollution simulation, this paper introduced the commonly used agricultural NPS pollution models and their uncertainty sources, with the focus on the research methods of model structure, related parameters, and input uncertainties as well as the advances in the applications of NPS pollution uncertainty research. It was suggested that in future studies, more attention should be paid on the quantitative analysis of the uncertainties of NPS pollution and on the key factors affecting the simulation of NPS pollution load, which could help to the prevention and management of agricultural NPS pollution, the improvement of related researches, and the formulation of effective measures for agricultural NPS pollution control.

Factors affecting the spatiotemporal differentiation of wetland water environmental quality.

2011, 30(07):  1551-1557. 

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The study on the spatiotemporal evolvement of wetland ecosystem water environmental quality and its related affecting factors is one of the hotspots in theoretical and applied wetland research. Based on the previous researches, this paper analyzed the spatiotemporal differentiation of wetland water environmental quality, constructed a classification system of related affecting factors, and summed up the characteristics of these factors in affecting wetland water environmental quality. Natural factors were served as the background constraint dimension in the evolvement of wetland water environment, and the anthropogenic processes of production and consumption were taken as the dominant factors causing the deterioration of wetland water environment. To adopt engineering and management measures to control the deterioration of wetland water environment would be the core mission of wetland management, but the potential accompanying negative effects should not be neglected. Up to date, the researches on the features and causes of the spatiotemporal evolvement of wetland water environmental quality are lack in integrity and integration. To address this problem, it would be a key issue to integrate the construction of a framework of related affecting factors and the research of landscape ecological characteristics of wetland water environment.

Comparison of NDVI simulation models for Bohai Rim region and the factors affecting NDVI.

2011, 30(07):  1558-1564. 

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Frequent and intensive human activities have caused enormous ecological and environmental pressures in Bohai Rim region. Based on the 2000-2005 SPOT-VGT dataset with 1 km spatial resolution and other data such as landform, climate, population, economy, land use, and transportation data, and by
the methods of global ordinary least square (OLS) and geographically weighted regression (GWR), this paper quantitatively analyzed the correlations of the NDVI in five provinces and municipalities of Bohai Rim with altitude, slope, temperature, precipitation, population density, GDP density, land use degree, distance to cities, and distance to main roads. Comparing with linear regression model, GWR model gave a much better fitting result, with the goodness of fit increased significantly from less than 0.3 to more than 0.7. Among the most sensitive factors affecting NDVI, positive factors were mainly altitude, temperature, and precipitation, while negative factors were mainly population density and GDP density. The regions where NDVI was positively sensitive to altitude were distributed in Liaohe Plain, hilly areas to the south of Changbai Mountains, and transitional zone from Yanshan to west coastal plain of Bohai bay, positively sensitive to temperature mainly located in southern Hebei Province and eastern coastal areas of Shandong Peninsula, and positively sensitive to precipitation were in Yanshan, north Taihang Mountains, and Zhangbei highland areas; while the regions where NDVI was negatively sensitive to population density and GDP density almost covered the whole Bohai Rim region except southern Hebei and northwestern and southwestern Shandong Province.

Feeding habits of silver pomfret (Pampus argenteus) in East China Sea based on stable isotope techniques.

2011, 30(07):  1565-1569. 

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By using stable isotope techniques, this paper analyzed the carbon and nitrogen stable isotope ratios of East China Sea silver pomfret (Pampus argenteus) and its potential feed materials, aimed to approach the potential food sources of P. argenteus in the Sea. The average δ¹³C and δ¹⁵N values of the P. argenteus were -18.22‰ and 8.16‰, and the δ¹³C and δ¹⁵N of the potential feed materials  ranged in -17.33‰--21.58‰ and 3.89‰-7.96‰, with the difference of 4.25‰ and 4.07‰, respectively. The potential food sources of the P. argenteus were mainly Sagitta, shrimps, jellyfish, cephalopods, fish larva, and zooplanktons, among which, Sagitta was the most important food source and contributed 24%-78% (averagely 57%) of the total food sources, followed by shrimps (11.8%), jellyfish (8.4%), cephalopods (7.1%), fish larva (5.0%), >1000 μm zooplanktons (4.9%), 500-1000 μm zooplanktons (3.2%), and 100-500 μm zooplanktons (2.6%). The results indicated that P. argenteus was an omnivorous fish, having different food sources from zooplankton to fish and complicated carbon and nitrogen sources.

Rubber cultivation and potable water shortage: A case in Geniu Village of Xishuangbanna.

2011, 30(07):  1570-1574. 

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The negative ecological effect caused by large area rubber cultivation in Xishuangbanna has being received broad attention. In this paper, questionnaire survey and field investigation were applied to analyze the relations between rubber cultivation and potable water shortage in Geniu administrative village, Jinghong County of Xishuangbanna. It was found that large scale rubber cultivation and potable water shortage for human and domestic animals were synchronically. The water resource consumption due to harvesting rubber product in 2009 was 3.4 times of that in 1995. 52.7% of villagers approved that rubber cultivation was one of factors causing the potable water shortage, and only 5.4% of villagers had the willing to mitigate potable water shortage by cutting down rubber area. It would be necessary to highlight the study of water consumption due to latex production by rubber trees and to bring the rubber farmers into solution of the eco-hydrological problems caused by rubber cultivation.

Reproductive strategies of Great Tit and Willow Tit in artificial nest boxes in Xiaolongmen forest park of Beijing.

2011, 30(07):  1575-1578. 

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From March to July 2009, an investigation was conducted to compare the reproductive parameters of Great Tit (Parus major) and Willow Tit (P. montanus) in artificial nest boxes in Xiaolongmen forest park of Beijing. A total of 100 nest boxes were hung at forest edge, 19 and 11 of which were occupied by P. major and P. montanus, respectively. The clutch size of P. major (8.21±0.25 eggs, n=19) was much larger than that of P. montanus  (6.18±0.23 eggs, n=11), but the hatching period of P. major (13617±0.83 d, n=12) was shorter than that of P. montanus (14.22±0.44 d, n=10) (P<0.01). There were no significant differences on the egg mass, egg size, nestling success, and fledging success between the two tit species (P>0.05). The nesting success of P. montanus (54.5%, n=11) was much higher than that of P. major (27.0%, n=19). It was suggested that P. major could have higher clutch size but lower fledging success, while P. montanus could have lower clutch size but higher fledging success.