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Table of Content

    18 December 2009, Volume 20 Issue 12
    Articles
    Temporal change in annual air temperature and heat island effect in a coastal city and an inland city at mid-latitude in China during 1956-1998.
    2009, 20(12):  2839-2846. 
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    Temporal changes in air temperature and urban heat island (UHI) effects during 1956-1998 were compared between a coastal city, Ji’nan, and an inland city, Xi’an, which were similar in latitude, size and development. During 1956-1978, except that the annual mean minimum temperature in Ji’nan increased by 0.37 ℃·10 a-1. the temperature variables in the two cities did not display any apparent  trend. During 1979-1998, all temperature variables of the two cities showed an increasing trend. Comparing with that in Ji’nan, the increasing rate of annual mean maximum temperature and annual mean temperature in Xi’an was greater, but that of annual mean minimum temperature was smaller. In the two cities, heat island effect occurred during 1956-1978 but without any apparent trend, whereas during 1979-1998, this effect increased with time, especially in Xi’an where the annual mean minimum temperature and annual mean temperature increased by 0.22 ℃·10 a-1 and 0.32 ℃·10 a-1, respectively. Both the level and the interannual variation of the heat island effect were much greater in Ji’nan than in Xi’an, but the increasing rate of this effect was greater in Xi’an than in Ji’nan. Obvious differences were observed in the increasing rate of annual mean maximum air temperature, annual mean air temperature, and annual mean minimum temperature as well as the heat island effect in Ji’nan, whereas negligible differences were found in Xi’an. Among the three temperature variables, annual mean minimum temperature displayed the most obvious increasing trend and was most affected by heat island effect, while annual mean maximum temperature was most variable inter-annually. Geographical location not only affected the magnitude of urban warming, but also affected the mode of urban warming and the strength of heat island effect.
    Characteristics and numerical simulation of surface albedo in temperate desert steppe in Inner Mongolia.
    2009, 20(12):  2847-2852. 
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    Based on the meteorological and biological observation data from the temperate desert steppe ecosystem research station in Sunitezuoqi of Inner Mongolia during growth season (from May 1st to October 15th, 2008), the diurnal and seasonal characteristics of surface albedo in the steppe were analyzed, with related model constructed. In the steppe, the diurnal variation of surface albedo was mainly affected by solar altitude, being higher just after sunrise and before sunset and lower in midday. During growth season, the surface albedo was from 0.20 to 0.34, with an average of 0.25, and was higher in May, decreased in June, kept relatively stable from July to September, and increased in October. This seasonal variation was related to the phenology of canopy leaf, and affected by precipitation process. Soil water content (SWC) and leaf area index (LAI) were the key factors affecting the surface albedo. A model for the surface albedo responding to SWC and LAI was developed, which showed a good performance in consistent between simulated and observed surface albedo.
    Spatiotemporal distribution patterns of photosynthetic photon flux density, air temperature, and relative air humidity in forest gap of Pinus koraiensis-dominated broadleaved mixed forest in Xiao Xing’an Mountains.
    2009, 20(12):  2853-2860. 
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    A continuous measurement of photosynthetic photon flux density (PPFD), air temperature, and relative air humidity was made in the forest gap in primary Pinus koraiensis-dominated broadleaved mixed forest in Xiao Xing’an Mountains to compare the spatiotemporal distribution patterns of the parameters. The diurnal maximum PPFD in the forest gap appeared between 11:00 and 13:00 on sunny and overcast days. On sunny days, the maximum PPFD during various time periods did not locate in fixed locations, the diurnal maximum PPFD occurred in the canopy edge of northern part of the gap; while on overcast days, it always occurred in the center of the gap.  The mean monthly  PPFD in the gap was the highest in June and the lowest in September, with the largest range observed in July. The maximum air temperature happened between 9:00 and 15:00 on sunny days, between 15:00 and 19:00 on overcast days, the locations were 8 m in the southern  part of gap center both on sunny and overcast days. From 5:00 to 9:00, the air temperature at measured positions in the gap was higher on overcast days than on sunny days; but from 9:00 to 19:00, it was opposite. The  mean monthly air temperature was the highest in June, and the lowest in September. The maximum relative humidity appeared between 5:00 and 9:00 on sunny and overcast days, and occurred in the canopy border of western part of the gap, with the relative air humidity on overcast days being always higher than that on sunny days. The  mean monthly relative humidity was the highest in July, and the lowest in June. The heterogeneity of PPFD was higher on sunny days than on overcast days, but the heterogeneities of air temperature and relative humidity were not obvious. The maximum PPFD, air temperature, and relative humidity were not located in the same positions among different months during growing season. For  mean monthly PPFD and air temperature, their variation gradient was higher in and around the center of gap; while for  mean monthly relative humidity, it was higher in the edge of forest gap.
    Environmental responses of four urban tree species transpiration in northern China.
    2009, 20(12):  2861-2870. 
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    By using thermal dissipation probes (TDP), this paper monitored the sap flow of four tree species (Cedrus deodara, Zelkova schneideriana, Euonymus bungeanus, and Metasequoia glyptostroboides) at the Laodong Park in Dalian City from June to August 2008, and the soil moisture content and micrometeorological variables were measured simultaneously. Due to the absence of water-stress in the habitat, the sap flow of all sampled trees had no significant correlation with soil moisture content (R2<0.05,P>0.211,n=1296). The correlation coefficient between solar radiation and sap flow reached 0.624-0.773 (P=0.00, n=1296) despite the existing hysteresis. Solar radiation had major effect (R2>0.700, P<0.05) during early morning (5:00-8:00) and late afternoon (18:00-20:00) when undergoing dramatic changes. As the main factor determining nighttime sap flow (R2>0.660,P<0.05, n=1872), vapor pressure deficit (VPD) had a correlation coefficient as high as 0.650-0.823 (P=0.00, n=1296) with the sap flow in whole-day scale. Meanwhile, the models constructed on the basis of VPD were able to explain 90% of daily sap flow change (P=0.00). The correlation coefficient between sap flow and wind speed was relatively smaller than the previous two (R2<0.380, P=0.00, n=1296), though showing significant correlation in affecting sap flow. Observations also detected the saturation phenomenon of sap flow to the environmental demands.
    Effects of different type urban forest plantations on soil fertility.
    2009, 20(12):  2871-2876. 
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    Aimed to study the effects of different urban forest plantations on soil fertility, soil samples were collected from eight mono-cultured plantations (Larix gmelinii, Pinus sylvestris var. mongolica, Pinus tabulaeformis var. mukdensis, Phellodendron amurense, Juglans mandshurica, Fraxinus mandshurica, Betula platyphylla, and Quercus mongolica) and one mixed plantation (P. sylvestris var. mongolica + F. mandshurica + Picea koraiensis + P. amurense + B. platyphylla) established in Northeast Forestry University’s Urban Forestry Demonstration Research Base in the 1950s, with two sites of neighboring farmland and abandoned farmland as the control. The soils in broadleaved forest plantations except Q. mongolica were near neutral, those in mixed plantation, L. gmelinii, P. sylvestris  var. mongolica, and P. tabulaeformis  var. mukdensis were slightly acidic, and that in Q. mongolica was acidic. The contents of soil organic matter, total N and P, available P and K, and hydrolysable N tended to decrease with soil depth. There existed significant differences in the chemical indices of the same soil layers among different plantations. The soil fertility was decreased in the order of F. mandshurica > P. amurense>mixed plantation > J. mandshurica > B. platyphylla > abandoned farmland > farmland > P. ylvestris var. mongolica > L. gmelinii > Q. mongolica > P. tabulaeformis var. mukdensis, suggesting that the soil fertility in broadleaved forest lantations except Q. mongolica and in mixed plantation increased, while that in needle-leaved forest plantations tended to decrease.
    Carbon emission from forest fires in Daxing’anling region in 2005-2007.
    2009, 20(12):  2877-2883. 
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    Based on field investigation, the burned areas and consumed fuel loadings in Daxing’anling region caused by forest fires in 2005-2007 were estimated by comparing the normalized difference vegetation index (NDVI) before and after burning. The burned areas were classified with fire intensity, and the carbon emission from the fires was estimated by the fuel consumption and the average carbon content of plants. It was estimated that the total burned area was 436512.5 hm2, of which, the severe, moderate, and light burned areas occupied 207178.4, 150159.2, and 79159.4 hm2, respectively. The consumed fuel loadings were 3.9×106 t in total, and the emitted carbon was 1.76×106 t, with 0.34×106, 0.83×106, 0.27×106, and 0.32×106 t from larch (Larix gmelini) forest, conifer and broadleaves mixed forest, broad-leaved forest, and grassland, respectively.
    Comparison of seed oil physicochemical characteristics among three cultivars of Jatropha curcas L .
    2009, 20(12):  2884-2890. 
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    Taking the cultivars Nanyou 1, 2, and 3 of barbadosnut (Jatropha curcas L.) with different genotypes that can grow and seed normally at the inshore land in Hainan as test materials, the characters of their seeds and the physicochemical characteristics of their seed oils were analyzed and compared. No significant differences were observed in the seed length, width, thickness, and surface area among the cultivars, but Nanyou 2 had greater 1000 seed mass and lower unsound kernel percentage than Nanyou 1 and Nanyou 3, suggesting that the seed satiation of Nanyou 2 was good and the fecundity was excellent. The kernel oil content of Nanyou 3 was significantly higher than that of Nanyou 1 and Nanyou 2, and there was no significant difference between Nanyou 1 and Nanyou 2. The seed oil peroxide value, refractive index, and saponification value of the three cultivars had no significant differences, but the acid value for Nanyou 2 was much lower than that for Nanyou 1 and Nanyou 3. The seed oil iodine value of the three cultivars was all below 100, and was significantly lower for Nanyou 2 than for Nanyou 1 and Nanyou 3. The fatty acids in the three cultivars seed oils were mainly oleic acid, palm itic acid, linoleic acid, stearic acid, and margaric acid, and dominated by unsaturated fatty acids. The contents of saturated fatty acids in Nanyou 2 seed oil were relatively higher than those in Nanyou 1 and Nanyou 3 seed oils, indicating that comparing with Nanyou 1, cultivars Nanyou 2 and Nanyou 3 had relatively good potential for application.
    Characteristics of soil seed banks in backwater area of Three Gorges Reservoir water-level-fluctuating zone at initial stage of river-flooding.
    2009, 20(12):  2891-2897. 
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    A germination test was made to study the characteristics of soil seed banks in the backwater area (including the flooded, non-flooded, and control areas of secondary bush and abandoned farmland) of Three Gorges Reservoir water-level-fluctuating zone. There existed significant differences in the soil seed banks between secondary bush and abandoned farmland, with an average seed density being 6991±954 seed per m2 and 26193±6928 seed per m2, respectively. Flooded area had the lowest seed density, while non-flooded area had the highest one. The seed density decreased with soil depth. A total of 118 species belonging to 45 families and 97 genera were detected in the soil seed banks of secondary bush and abandoned farmland, most of which were annual and perennial herbage species, belonging to Asteraceae, Poaceae, Scrophulariaceae, and Cruciferae. Among the 118 species, there were 34 species (occupying 28.8%) whose individuals accounted for less than 0.01% of the total. In the soil seed banks of secondary bush and abandoned farmland, the species number was similar, species diversity index and evenness index were relatively high, but the dominant species differed greatly, and the ecological dominance was relatively low. The species diversity in non-flooded area and the ecological dominance in flooded area were the highest, and the similarity index between the flooded and non-flooded areas was the highest.
    Leaf photosynthetic potential in canopy layers of un-thinned and thinned apple orchards.
    2009, 20(12):  2898-2904. 
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    Through the comparison of leaf photosynthetic potential and of photosynthetically active radiation (PAR), leaf nitrogen concentration (Nl), and mass per unit leaf area (Ml) in different canopy layers of un-thinned orchard (UOD) and thinned orchard (TOD), this paper studied the effects of UOD rebuilding on the use efficiencies of PAR and nitrogen, and their relationships to the fruit yield and quality. Thinning obviously improved the radiation environment in canopy. The radiation distribution in TOD canopy was more uniformly than that in UOD canopy, and the invalid space with relative PAR (PARr) less than 30% in TOD approached to zero, while the minimum mean PARr in UOD was 17%, and the space under 0.3 of relative canopy height was invalid. The leaf photosynthetic efficiency in TOD was notably improved. Comparing with that in UOD, the photsynthetic rate (Pn) at the middle and bottom of the canopy in TOD was increased by 7.8% and 10.2%, respectively. Meanwhile, the photosynthetic potential parameters such as maximum carboxylation rate (Vmax) and maximum electron transfer rate (Jmax) also increased remarkably in TOD. The leaf photosynthetic potential had significant correlation with Nl, and the Nl was strongly correlated with PARr. As a result, leaf photosynthetic potential and PARr could be estimated according to the spatial distribution of relative leaf nitrogen concentration (Nlr).
    Effects of soil acidity on Pinus resinosa seedlings photosynthesis and chlorophyll fluorescence.
    2009, 20(12):  2905-2910. 
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    Red pine (Pinus resinosa) is one of the most important tree species for timber plantation in North America, and preliminary success has been achieved in its introduction to the mountainous area of Northeast China since 2004. In order to expand its growth area in other parts of Northeast China, a pot experiment was conducted to study the adaptability of this tree species to varying soil acidity. P. resinosa seedlings were grown in soils with different acidity (pH=4.5, 5.5, 6.5, 7.5, and 8.0) to test the responses of their photosynthesis and chlorophyll fluorescence parameters to soil pH levels, and the appropriate soil acidity was evaluated. Dramatic responses in chlorophyll a and b contents, Pn, and chlorophyll fluorescence parameters (Fo,Fm,Fv,Fv/Fm, and ΦPSⅡ) were detected under different soil acidity (P<0.05), with the highest chlorophyll content and Pn under soil pH 5.5, and significantly lower chlorophyll content and Pn under soil pH 7.5 and 8.0. The chlorophyll content and Pn were 41% and 50%, and 61% and 88% higher under soil pH 5.5 than under soil pH 7.5 and 8.0. The seedlings had a significant photosynthetic inhibition under soil pH 7.5 and 8.0, but the highest Fv/Fm and ΦPSⅡ under soil pH 5.5. Comparing with those under soil pH 7.5 and 8.0, the Fv/Fm and ΦPSⅡ under soil pH 5.5 were 8% and 12%, and 22% and 35% higher, respectively. It was suggested that soil pH 5.5 was most appropriate for P. resinosa growth.
    Carbon sequestration of young Robinia pseudoacacia plantation in Loess Plateau.
    2009, 20(12):  2911-2916. 
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    In order to understand the carbon sequestration of ecological forests in Loess Plateau, a comparative study was made on the organic carbon density (OCD) of soil, litter, and plant organs in an 8-year-old Robinia pseudoacacia plantation and nearby barren land. Comparing with the barren land, the young R. pseudoacacia plantation had a decrease (0.26 kg·m-2) of soil OCD, but the OCD in its litter, root system, and aboveground organs increased by 121.1%, 202.0%, and 656.7%, respectively, with a total carbon sequestration increased by 3.3% annually, which illustrated that R. pseudoacacia afforestation on Loess Plateau had an obvious positive effect on carbon sequestration.
    Carbon cycle in ten kinds of forest ecosystem in Guangzhou City.
    2009, 20(12):  2917-2924. 
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    Based on an extensive collection of information and experimental data, this paper studied the carbon cycle in ten kinds of forest ecosystem in Guangzhou, China, aimed to explore the carbon cycling patterns in southern subtropical forest ecosystems. For the test ecosystems, their carbon density ranged from 108.35 to 151.85 t C·hm-2, with 10.85-48.86 t C·hm-2 in tree layer and 87.74-99.01 t C·hm-2 in soil layer (0-60 cm), being lower than the national average. There were 4.41-9.15 t C·hm-2·a-1 flowed from atmosphere to vegetation stratum, 0.74-2.06 t C·hm-2·a-1 from vegetation stratum to soil, and 3.94-5.42 t C·hm-2·a-1 from soil to atmosphere, i.e., the forest systems absorbed 0.47-4.97 t C·hm-2·a-1 from atmosphere. The net ecosystem production (NEP) varied with forest stand, being higher for broadleaved forest than coniferous forest, mixed forest than pure forest, and natural secondary forest than artificial forest.
    Coverage extraction and up-scaling of sparse desert vegetation in arid area.
    2009, 20(12):  2925-2934. 
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    Five kinds of remote sensing inversion models, i.e., linear spectral un-mixing model, sub-pixel un-mixing model, maximal gradient difference model, and two modified maximal gradient difference models, were used to derive fc from remote sensing data, and the results were compared with those measured in field, aimed to select appropriate model for deriving the data of the coverage of sparse desert vegetation in arid area. The virtual multi-scale coverage images were generated by using the simple mean scale extending method to verify the inversion information from MODIS data. It was shown that linear un-mixing spectral model had a higher precision than the other models, being applicable for deriving the data of the coverage of sparse desert vegetation, but the selection of end member was rather difficult and affected the application of the model. Sub-pixel un-mixing model was universal, high precision could be obtained based on finely detailed vegetation map, but needed to measure lots of parameters. Maximal gradient difference model was simple and easy to perform, by which, the values of the coverage of crops and bare land predicted with the original model were close to the field-measured results, but the values of the coverage of sparse vegetation were underestimated. The results predicted by the modified three-band maximal gradient difference models were close to the field-measured values, and the inversed results of vegetation coverage under different scales were ideal, indicating that these models were reliable to effectively extract the information of the coverage of sparse vegetation in arid area.
    Physiological differences and their genetic backgrounds of Erigeron breviscapus populations under enhanced UV-B radiation.
    2009, 20(12):  2935-2942. 
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    A simulation experiment was conducted under greenhouse condition to study the effects of enhanced UV-B radiation (280-320 nm) on the flavonoid and MDA contents and antioxidant enzyme activities of six Erigeron breviscapus populations, and the intraspecific differences in physiology to the UV-B radiation. The related genetic backgrounds of E. breviscapus populations were also analyzed by ISSR analysis. Under enhanced UV-B radiation, the flavonoid content of E. breviscapus populations D01, D53, D63 and D65 increased significantly at seedling, flowering, and maturing stages, and the MDA content decreased significantly at seedling and flowering stages; while the flavonoid content of D47 and D48 increased significantly at flowering stage but decreased at maturing stage, and the MDA content increased significantly at the three growth stages. The POD and APX activities of D01 at the three growth stages, CAT activities at seedling and flowering stages, and SOD activity at flowering stage significantly increased; the SOD, CAT and APX activities of D47 at the three growth stages and the POD activity at maturing stage decreased significantly; the POD and APX activities of D48 at the three growth stages and the SOD activity at seedling and maturing stages decreased significantly; the SOD and APX activities of D53 at seedling and flowering stages and the CAT activity at flowering stage increased significantly; the SOD, POD and APX activities of D63 at the three growth stages increased significantly; and the CAT and APX activities of D65 at maturing stage had no significant changes, but the test enzyme activities at the three growth stages increased significantly. D01, D53, D63, and D65 were tolerant to UV-B radiation, while D47 and D48 were sensitive to UV-B radiation. The responses of E. breviscapus populations to enhanced UV-B radiation varied with growth stage, being in the order of flowering stage > seedling stage > maturing stage. There was an obvious genetic polymorphism among the six E. breviscapus populations, which were divided into two groups at the level of 0.11 of genetic distance, one group including D01, D53, D63 and D65, and the other including D47 and D48. This classification was consistent with the results of physiological response index to UV-B radiation.
    Soil enzyme activities in a Pleioblastus amurus plantation in Rainy Area of West China under simulated nitrogen deposition.
    2009, 20(12):  2943-2948. 
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    From November 2007 to May 2009, a simulation test was conducted in a Pleioblastus amarus plantation in Rainy Area of West China to study the effects of nitrogen deposition on the activities of soil enzymes. Four treatments were installed, i.e., control (0 g N·m-2·a-1), low nitrogen (5 g N·m-2·a-1), medium nitrogen (15 g N·m-2·a-1), and high nitrogen (30 g N·m-2·a-1). Half year after N deposition, 0-20 cm soil samples were collected monthly, and the activities of peroxidase, polyphenol oxidase, cellulase, sucrase, urease, and acid phosphatase were determined. All test enzyme activities had apparent seasonal variation, with the peak of cellulase, sucrase, and acid phosphatase activities in spring, of urease activity in autumn, and of peroxidase and polyphenol oxidase activities in winter. Nitrogen deposition stimulated the activities of polyphenol oxidase, sucrase, urease, and acid phosphatase, inhibited cellulase activity, but had no significant effects on peroxidase activity. The test P. amurus plantation ecosystem was N-limited, and nitrogen deposition stimulated the decomposition of soil organic matter by microbe-enzyme system.
    Effects of different ecological conditions on grain quality and RVA profile of japonica rice from Yunnan of China and Korea.
    2009, 20(12):  2949-2956. 
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    Taking sixteen japonica rice varieties from Yunnan of China and Korea growing at three locations with different altitudes in Yunnan Plateau as test materials, this paper studied the effects of different ecological conditions on their grain quality, including brown rice length (BRL), brown rice width (BRW), lengthwidth ratio (L/W), chalky rate (CR), whiteness (WH), amylose content (AC), protein content (PC), and alkali digestion value (ADV), and their starch RVA profile, including peak viscosity (PKV), hot viscosity (HTV), final viscosity (FLV), breakdown viscosity (BDV), setback viscosity (SBV), consistence viscosity(CTV), peak time (PeT), and pasting temperature (PaT). Of all the test parameters, SBV had the largest coefficient of variation. The coefficients of variation of BRL, CR, AC, PC, ADV, FLV, SBV, and PeT of Yunnan varieties were higher than those of Korean varieties, while the BRW, L/W, WH, PKV, HTV, BDV, CTV, and PaT of Korean varieties had higher coefficients of variation than those of Yunnan varieties. With increasing altitude, the BRL, BRW, L/W, WH, AC, ADV, FLV, and CTV of Yunnan varieties, and the BRL, BRW, WH, PC, PKV, HTV and BDV of Korean varieties decreased significantly, while the CR, PC, HTV, and PeT of Yunnan varieties, and the L/W, AC, ADV, SBV and CTV of Korean varieties increased significantly. The CR of Korean varieties had no obvious change. The PKV, BDV, and PaT of Yunnan varieties and the PaT of Korean varieties increased after an initial decrease, whereas the SBV of Yunnan varieties and the FLV and PeT of Korean varieties were in reverse.
    Genetic characteristics of wheat functional leaves at filling stage under different water regimes.
    2009, 20(12):  2957-2963. 
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    Taking one hundred and fifty doubled haploid (DH) lines of winter wheat cultivars Hanxuan 10×Lumai 14 as well as their parents as test materials, the genetic bases of top three leaves length, breadth, and angle at mid-filling stage, and their correlations with yield traits were studied under two water regimes rainfed (drought stress, DS) and well-irrigation (WI) in 2005-2007. Under DS, the leaf length and width of DH lines and their parents were significantly lower than those under WI, whereas the leaf angle had a miscellaneous variation. Under the two water regimes, all the test traits of DH lines had a transgressive segregation, with the variation coefficients ranged from 5.1% to 45.9%. The heritability and gene numbers for the given traits showed great differences. Under WI and DS, the heritability of flag leaf angle (FLA) was the highest (91% and 97%, respectively), and that of the third leaf angle (TLA) was the lowest (23% and 31%, respectively). However, the gene number for FLA (4 and 2 under WI and DS, respectively) was the least, and that of TLA (21 and 25, respectively) in 2007 was the most. Interactive effects were observed among the genes controlling FLA, second leaf angle (SLA), and TLA under WI and DS, and controlling third leaf length (TLL) under WI.  The grain number per spike and the grain weight per spike were positively correlated with the length and width of top three leaves, and the thousand-grain weight and the yield per plant were significantly correlated with TLL, FLA, and SLA, but all correlation coefficients were smaller (<0.481). It was suggested that the selection of top three leaves length and width should be carried out in the early generations of breeding procedure, while that of leaf angles should be carried out in advanced generations. An appropriate soil moisture regime retained in the critical growth period of the leaves would promote their growth and contribute to the grain yield.
    Effects of high- and low temperature stresses on ascorbic acid metabolism system in potato leaves.
    2009, 20(12):  2964-2970. 
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    In order to investigate the responses of ascorbic acid (AsA) metabolism system in potato leaves to high and low temperature stresses, a pot experiment was conducted with potato plants exposed to 40  ℃ or 5 ℃, with the leaf AsA content, mRNA expression level of GalLDH and DHAR genes, activities of GalLDH, DHAR, APX, MDHAR and GR, and contents of hydrogen peroxide (H2O2 ) and malondialdehyde (MDA) determined. Under the exposure to 40 ℃, the leaf AsA content increased rapidly and reached the highest (43.7% higher than the control) at 6 h, followed by a rapid decrease. Under the exposure to 5 ℃, the AsA content also increased first, reached the highest (27.7% higher than the control) at 9 h, and then decreased. Under the two temperature regimes, the activities of leaf GalLDH, DHAR, APX, MDHAR and GR decreased after an initial increase, the mRNA expression level of GalLDH and DHAR genes showed the similar changes with their corresponding enzyme activities, and the leaf MDA and H2O2 contents increased remarkably after 24 h. All the results suggested that the AsA metabolism system in potato leaves was stimulated in the early period of high- and low temperature stresses, but its function declined gradually with the duration of the stresses.
    Effects of ecological factors on the dough extensograph parameters of different winter wheat cultivars.
    2009, 20(12):  2971-2976. 
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    In 2000-2001 and 2001-2002, six representative winter wheat cultivars Yumai 34, Gaomai 8901, Yumai 49, Yumai 70, Luoyang 8716, and Yumai 50 were consecutively grown at five locations (Xinyang, Zhumadian, Xuchang, Wuzhi, and Tangyin) with latitudes varying from 32° N to 36° N in Henan Province, aimed to understand the relationships of winter wheat dough extensograph parameters with genetic and ecological factors. The dough extensograph parameters were more affected by genetic factors than by ecological factors. Cultivars Yumai 34 and Gaomai 8901 had significantly higher maximum resistance and extension area than the other four test cultivars, and significant differences in the dough extensograph parameters were observed between the cultivars grown in the south region (Xinyang and Zhumadian) and in the north region (Wuzhi and Tangyin) of the Province. The change patterns of  dough extensograph parameters with latitude differed in 2000-2001 and in 2001-2002, and the effects of climatic factors on the dough extensograph parameters varied with year. In 2001-2002, the precipitation at the stage from grain-filling to maturing affected the dough extensograph parameters significantly. Our results suggested that in order to improve the dough extensograph parameters of winter wheat, local meteorological conditions should be taken into full consideration in the soil water management at late-maturing stage.
    Effects of different planting patterns on the senescence characteristics of flue-ured tobacco roots and leaves.
    2009, 20(12):  2977-2982. 
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    With flue-ured tobacco (Nicotiana tabacum) cultivar K326 as test material, a field experiment was conducted at Nanxiong area of Guangdong Province in 2008 to study the effects of four planting patterns, i.e., single-ow ridge + film mulching at early stage, single-ow ridge + film mulching at early and late stages, double-ow concave ridge + film mulching at early stage, and double-row concave ridge + film mulching at early and late stages, on the senescence characteristics of its roots and leaves, and the economic traits of its leaves. Comparing with other three planting patterns, double-row concave ridge + film mulching at early and late stages promoted the root growth of test cultivar during its whole growth period, with the root vigor increased significantly. Meanwhile, the leaf chlorophyll content and protective enzymes (SOD and POD) activities were higher, and the MDA content was lower. The leaf yield, output value, average price, and the proportion of superior leaves were also higher. Double-ow concave ridge + film mulching at early and late stages alleviated the senescence characteristics of roots and leaves, and improved the economic traits of flue-cured tobacco leaves, being the efficient planting pattern to product high-uality flue-ured tobacco leaves in Nanxiong tobacco-rowing area of Guangdong Province.
    Effects of rotation and fallowing on the microbial communities and enzyme activities in a solar greenhouse soil under continuous cucumber cropping.
    2009, 20(12):  2983-2988. 
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    A pot experiment was conducted to study the effects of rotation and fallowing on the microbial communities and enzyme activities in a greenhouse soil continuously cropped with cucumber and on the growth and yield of followed cucumber. Comparing with continuous cropping, rotation improved the components of soil microbial communities, which was manifested in the increase of bacteria and actinomycetes and the decrease of fungi. Rotation and fallowing enhanced the activities of soil invertase, urease, catalase, and polyphenol oxidase significantly. The quantities of soil bacteria and actinomycetes and the activity of soil invertase increased at the fruiting stage of cucumber plants, being the maximum at harvest stage, but decreased thereafter. In contrast, the quantity of soil fungi had a linear increase, and the activities of soil urease, catalase, and polyphenol oxidase decreased gradually during fruit development. Welsh onion and waxy maize promoted the growth and fruiting of the followed cucumber plants significantly, being the optimal rotation crops for cucumber.
    Response of photosynthetic characteristics of peanut seedlings leaves to low light.
    2009, 20(12):  2989-2995. 
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    To investigate the effects of shading and light recovery on the photosynthetic characteristics of peanut seedlings leaves, different shading treatments including no shading, 27% shading, 43% shading, and 77% shading were performed with black sunshade net at the seedling stage of two peanut cultivars Fenghua 1 and Fenghua 2, with related parameters determined. It was shown that with the increase of shading degree, the leaf chlorophyll content, actual PSII photochemical efficiency under irradiance (ФPSⅡ), and maximum PSⅡ photochemical efficiency (Fv/Fm) of test cultivars increased, while the Chl a/b ratio and photosynthetic rate(Pn) decreased. On the first day after light recovery, the Pn and stomatal conductance (Gs) decreased while the intercellular CO2 concentration (Ci) increased with increasing shading degree when measured under high light, but the Pn increased and the Gs and Ci decreased with increasing shading degree when measured under low light. The ratio of Pn measured under low light to that measured under high light increased significantly. With increasing shading degree, the light compensation point, light saturation point, CO2 compensation point, CO2 saturation point, and carboxylation efficiency decreased, while the apparent quantum yield increased. After the removal of shading, the Pn, ФPSⅡ, and Fv/Fm under natural light decreased immediately, but increased gradually 3-5 days after. 15 days after light recovery, the Pn, ФPSⅡ and Fv/Fm in treatment 27% shading recovered to the level of no shading. As for the other treatments, the restored extent differed with shading degree and test variety. In the same treatments, the leaf chlorophyll content, Pn, and ФPSⅡ of Fenghua 1 were higher than those of Fenghua 2. The results demonstrated that shading at seedling stage improved the capabilities of test varieties in using low light, but reduced the capabilities in using high light.
    Construction effect of fertile cultivated layer in black soil.
    2009, 20(12):  2996-3002. 
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    The clayey farmland soil in black soil region of Northeast China, due to the existence of thicker plough pan created by unreasonable tillage, is a main limiting factor for local agricultural production. In this paper, a field experiment was conducted to study the construction effect of fertile cultivated layer on crop yield, soil physical properties, soil moisture content, and soil microbial number. After the construction of fertile cultivated layer, the soil had a thicker cultivated layer, and the crop yield was increased. Comparing with traditional tillage, applying straw and organic manure into 20-35 cm soil layer decreased soil bulk density by 9.88% and 6.20%, increased soil porosity by 9.58% and 6.02%, and enhanced soil saturated hydraulic conductivity by 167.99 and 73.78%, respectively, indicating that the construction of fertile cultivated layer could improve soil aeration and water permeability, and enhance the infiltration of rainfall. The soil moisture content and water use efficiency under the application of straw and organic manure into plough pan were higher than those under traditional tillage, and a positive correlation was observed between the moisture content in 0-35 cm soil layer and the emergence of maize seedlings. Due to the increased organic carbon source and aeration in the constructed fertile cultivated layer, soil microbial number was also increased.
    Effects of high-yielding rice cultivar and cultivation pattern on methane emission from paddy field.
    2009, 20(12):  3003-3008. 
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    A field experiment was conducted to observe the effects of high-yielding rice cultivars (early rice Luliangyou No.996 and Chuanfeng No.1, and late rice T you No.259) and cultivation patterns (direct sowing and transplanting) on the methane emission from paddy field. The methane emission from early rice field before drying was 52%-73% of the total, while drainage and drying decreased the methane emission significantly. For late rice field, the methane emission during vegetative growth stage was 70% of the total. Under direct sowing of early rice, the average methane flux was lower, but the total methane emission was higher, compared with those under transplanting. As for late rice, both the average methane flux and the total methane emission were higher under direct sowing than under transplanting. There existed significant differences in the methane emission per unit grain production of early rice and late rice between direct sowing and transplanting. The methane emission per unit grain production under direct sowing of early rice super hybrid was increased by 4.84 g CH4·kg-1, compared with that under transplanting, and the emission under direct sowing of conventional early rice was increased by 3.48 g CH4·kg-1, compared with that under transplanting. The emission under direct sowing of hybrid rice was 6.67 g CH4·kg-1 higher than that under transplanting. In the same cultivation area and the same time period of direct sowing and transplanting, the methane emission was in the order of direct sowing of conventional early rice > transplanting of conventional early rice > direct sowing of early rice super hybrid > transplanting of early rice super hybrid, and direct sowing of late rice > transplanting of late rice.
    Effects of exogenous NO on the growth and antioxidant enzyme activities of cucumber seedlings under NO3- stress.
    2009, 20(12):  3009-3014. 
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    In this study, cucumber seedlings were cultivated in nutrient solution added with different concentration (0.05, 0.1, 0.2, and 0.3 mmol·L-1) sodium nitroprusside (SNP) as nitric oxide (NO) donor to study the effects of exogenous NO on the growth of cucumber seedlings and the activities of antioxidant enzymes in cucumber leaves under NO3- stress. Under the stress of 140 mmol·L-1 NO3- ,treating with 0.1 mmol·L-1 of SNP for 1 d or 7 d increased the leaf soluble protein content and superoxidase (SOD), catalase (CAT), and ascorbic acid peroxidase (APX) activities, and decreased the leaf malondialdehyde (MDA) content significantly, suggesting that exogenous NO could enhance the capacity of cucumber seedlings in scavenging active oxygen species, protect the seedlings from the peroxidation of membrane lipids, and promote the seedlings growth and increase their resistance to high concentration NO3- stress. After the cucumber seedlings grew in 0.3 mmol·L-1 of SNP for 7 d, the activities of leaf SOD, POD, and CAT decreased, and the MDA content increased, resulting in the injury of cucumber seedlings. It was indicated that certain concentration (0.1-0.2 mmol·L-1) exogenous NO could alleviate the NO3- stress to cucumber seedlings.
    Effects of chemical ripeners on chlorophyll content and antioxidant enzyme activities of rapeseed pod.
    2009, 20(12):  3015-3019. 
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    A field experiment was conducted to study the effects of ripeners Diguat and Roundup on the chlorophyll content, activities of catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD), cell membrane permeability, and malondialdehyde (MDA) content of rapeseed pods. Under effects of Diquat, the chlorophyll content decreased, while the activities of SOD, POD, and CAT, cell membrane permeability, and MDA content increased significantly, leading to the peroxidation of membrane lipid. These effects increased with increasing Diquat concentration. After treated with Roundup, the chlorophyll content had less change, activities of SOD, POD, and CAT increased slowly, and cell membrane permeability and MDA content had no obvious increase. With the increasing time of ripeners treatment, the activities of protective enzymes were inhibited to different degree, possibly due to the changes of molecular structure of antioxidant enzyme system under effects of the ripeners.
    Microbial degradation of soil polycyclic aromatic hydrocarbons (PAHs) and its relations to soil bacterial population diversity.
    2009, 20(12):  3020-3026. 
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    A laboratory simulation test was conducted to study the microbial remediation of soils contaminated by medium and low concentration polycyclic aromatic hydrocarbons (PAHs), and the relationships between the degradation of PAHs and the inoculated and indigenous microbes. The addition of high-effective PAHs-degrading bacteria promoted the biodegradation of soil PAHs, and the effect was remarkable in the first two weeks. The biodegradation of test PAHs was phenanthrene<anthracene<pyrene<benzo[a]pyrene<chrysene, and negatively correlated with the diversity/abundance of soil bacterial population. In the same treatments, soil bacterial population structure varied less with time, and hence, to increase the activity of indigenous microbes would be an effective way to remediate the farmland soils contaminated by medium and low concentration PAHs.
    Optimization of LCMSMS determination method for steroid compounds in wastewater and its application in feedlot wastewater.
    2009, 20(12):  3027-3033. 
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    Taking Solid-Phase Extraction (SPE) as pre-treatment process, a laboratory experiment was conducted by adopting the technology of High Performance Liquid Chromatography-Tandem Mass Spectrometry (HPLCMSMS) to develop a method to determine the concentrations of 13 steroids in feedlot wastewater. Atmospheric Press Chemical ionization (APCI) source was applied and operated in negative ion model, with the parameters of Chromatography and Spectrometry being optimized. Quasi-molecular ion peak [M+H]+ appeared in the full scan of the first quadrupole of mass spectrometer (Q1) of Testosterone propionate and other 6 steroid compounds, while quasi-molecular ion peak [M+H-H2O]+ appeared in the full scan of Q1 of rest 6 steroid compounds. The linear range of the 9 points calibration curve for the 13 target compounds was determined to be from 1 to 1000 ng·ml-1, and the calibration curve regression correlation coefficients (R) were always above 0.9990 for all sample batches. The average recovery rate of all target compounds was 83.75%-111.50%, and the methodological stability was determined to be acceptable, with the relative standard deviations between 2.02%-14.21%(n=6). Except that the limit of detection (LOD) of Mestradiol and Oestriol was higher than 15 ng·ml-1, all the other target compounds had a LOD lower than 5 ng·ml-1. In the determination of real samples from feedlot wastewater, the developed method represented a good profile to all target compounds at different concentrations in each stage of treatment.
    Changes of soil enzyme activities in heavy metals polluted region: A case study in a wastewater-irrigated agricultural area near a smelter in Xinluo District of Longyan City, Fujian Province
    2009, 20(12):  3034-3042. 
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    Surface soil samples were collected from a wastewater-irrigated agricultural area near a smelter in the Xinluo District of Longyan City, Fujian Province, and their basic physical and chemical properties, activities of urease, cellulase, alkaline phosphomonoesterase, polyphenol oxidase and catalase, and contents of Cu, Cd, Pb and Zn were determined, aimed to approach the effects of heavy metals pollution and soil properties on the activities of soil enzymes. Correlation analysis showed that the total and available contents of soil Cu, Cd, Pb and Zn had significant positive correlations with the activities of soil urease, cellulase, alkaline phosphomonoesterase and polyphenol oxidase, but significant negative correlation with the activity of soil catalase. Soil pH had significant positive correlation with the activity of soil alkaline phosphomonoesterase, and soil silt content had significant negative correlation with the activity of soil catalase. Path analysis showed that Cu, Cd, Pb and Zn pollution promoted the activities of soil urease, cellulase and polyphenol oxidase, but had less effects on the activity of soil alkaline phosphomonoesterase. Soil available Cu, Cd, Pb and Zn didn’t directly affect the activity of soil catalase, but indirectly inhibited it significantly. Soil physical and chemical properties had greater effects on soil enzyme activities, e.g., alkaline-hydrolyzable N directly inhibited the activity of soil urease, total P directly stimulated the activities of soil alkaline phosphomonoesterase and catalase and indirectly stimulated the activity of soil cellulase via available P, available P directly promoted the activity of soil cellulase but inhibited the activities of soil alkaline phosphomonoesterase and catalase, total K directly inhibited the activities of soil alkaline phosphomonoesterase and polyphenol oxidase, available K stimulated the activity of soil catalase via available P, and particle composition had significant effects on the activities of soil polyphenol oxidase and catalase. The above results demonstrated that because of the complicated and uncertain relationships between the contents of soil Cd, Pb, Zn and Cu and the activities of the five soil enzymes, it should be cautious to use the test enzyme activities to indicate soil heavy metals pollution.
    Pollutant production and discharge from livestock and poultry industries and land carrying capacity in Zhejiang Province.
    2009, 20(12):  3043-3048. 
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    Based on the investigation of pollutant production and discharge from a typical scale pig farm in Zhejiang Province at three pig growth stages (piglets, fattening pigs, and sows) in the autumn and winter 2007 and the spring and summer 2008, the coefficients of pollutant production and discharge from the pigs as well as the total annual pollutant production and discharge from the farm were estimated. In the meantime, the annual application amount of animal manure to the farmlands in Zhejiang Province was estimated by using these coefficients and the livestock and poultry inventories in Zhejiang Province in 2007. It was estimated that the total amount of applied animal manure in the Province in 2007 was 2106.8×104 t·a-1, containing 13.57×104 t·a-1 of N, 6.7×104 t·a-1 of P, 0.11×104 t·a-1 of Cu, and 0.20×104 t·a-1 of Zn. The pig-manure equivalent farmland carrying capacity in the Province was 16.66 t·hm-2·a-1, and the average alarm limit was 0.37. The application of animal manure in some areas of Zhejiang Province had exceeded the alarm limit for the land carrying capacity, and made a potential environmental threat.
    Community structure of soil meso- and micro-fauna in different habitats of urbanized region.
    2009, 20(12):  3049-3056. 
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    Investigations were made in May, June, and November 2007 and January 2008 to study the structural characteristics and their seasonal variations of soil meso- and micro-fauna communities in six habitats of three land use types (forest land, constructed grassland and farmland) in Tianhe District of Guangzhou City. The horizontal spatial distribution of soil fauna differed with habitat. During the investigation periods, the Botanical Garden of South China Agricultural University had the highest individual number (1286) of soil meso- and micro-fauna, while the farmland, especially in the Fenghuang Street area, had the lowest number of individuals and groups. The seasonal variation of the individual number was in  order of autumn (1815)>spring (1623)>winter (1365)>summer (1276). Hierarchical clustering and detrended correspondence analysis also showed that the community composition of soil meso- and micro-fauna in different habitats exhibited distinct seasonal variation. In the same seasons, the community structure and composition of soil meso- and micro-fauna in different habitats were correlated to the degrees of human interferences and the properties of soil environment.
    Community structure of rotifer in Mingzhu Lake of Chongming Island, Shanghai.
    2009, 20(12):  3057-3062. 
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    A comprehensive survey on the quantitative distribution, community structure, species composition, dominant species, and species diversity of rotifer was conducted in the Mingzhu Lake of Chongming Island, Shanghai in January-December, 2008. There were 27 species of rotifer in the Lake, belonging to 8 families and 11 genera. The dominant species were Polyarthra trigla, Trichocerca pusilla, Brachionus calyciflorus, Brachionus forficula, and Philodina sp. The rotifer had an average annual density of (1505.42±1304.63) ind·L-1, and an average annual biomass of (2.012±2.146) mg·L-1. The Shannon-Wiener diversity index, evenness index, and richness index of rotifer community in the Lake were relatively low, while the dominance index was rather high, indicating that the community structure of the rotifer was unstable. The  E/O value wes 1.61±1.46 on average, and the QB/T values wes 1.23±0.84 on average. Water temperature was the main factor affecting the rotifer distribution. Biological assessment of water quality suggested that the Mingzhu Lake was on eutrophication.
    Effects of starvation and refeeding in winter on the growth, survival, and biochemical composition of different size Ruditapes philippinarum.
    2009, 20(12):  3063-3069. 
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    From December 2007 to April 2008, a laboratory experiment was conducted to study the effects of various starvation periods followed by the same refeeding period on the growth, survival, and biochemical composition of different  size Ruditapes philippinarum at water temperature 3.0 ℃-4.2 ℃, salinity 25-27, and pH 7.90-8.16. No significant differences in the growth characteristics of R. philippinarum at low temperatures were observed among different  size groups. The tolerance to starvation increased with increasing  size, while the survival rate decreased with increasing starvation period.  the point-of-no return (PNR50) was not observed during the study period. For the larger size group (7 mm), the body moisture and lipid concentrations generally decreased with increasing starvation period. During starvation, the body protein content increased initially as a result of lipid being utilized for energy, but decreased thereafter when the lipid was depleting. Ash content remained unchanged during the study period, and was not affected by starvation or refeeding.
    Effects of exoelectrogens and electron acceptors on the performance of microbial fuel cells.
    2009, 20(12):  3070-3074. 
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    Two types of microbial fuel cells (MFCs) were adopted to analyze the effects of exoelectrogens and electron acceptors on the electrogenesis performance of MFCs. One was conventional MFCs inoculated with sewage and using nitrate as electron acceptor (S-MFCs), and the other one was  modified MFCs inoculated with anaerobic treated wastewater and using ferricyanide as electron acceptor (A-MFCs). Exoelectrogens and electron acceptors had substantial effects on the acclimation period and the power output period of MFCs. The acclimation period was reduced from 500 h for S-MFCs to 430 h for A-MFCs, and the power output period was prolonged from 100 h for S-MFCs to 350 h for A-MFCs. The modified MFCs increased the removal of COD and the output of voltage by 25% and 300%, respectively. To select appropriate exoelectrogens and  electron acceptors were crucial to the improvement of MFCs performance.
    Evaluation of cultural service value of aquaculture pond ecosystem: A case study in a water conservation area of Shanghai.
    2009, 20(12):  3075-3083. 
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    Pond aquaculture has existed in China for thousands of years, which has not only contributed great economic value, but also presented cultural value for human beings. With the development and upgrading of Chinese economy and culture, these values will be highlighted further. To evaluate the cultural service value of pond aquaculture ecosystem would provide a scientific base to the policy-making to avoid or reduce the wrong designmaking or avoid the policy-malfunction, and also, to promote the development of aquaculture and related recreational fishing industry, increase the added value of aquaculture and the income of fish-farmers, and promote the economic development of rural area. Based on the survey data from the aquaculture ponds in the water conservation area of Dianshan Lake in Qingpu District of Shanghai and the related statistical data, the cultural service value including recreational value and existence value of the aquaculture pond ecosystem in the area was estimated by means of travel cost method (TCM) and contingent valuation method (CVM). The total cultural service value of this ecosystem was about 213 million Yuan·a-1 or 231296.69 Yuan·hm-2·a-1, being 5.25 times of the market value of aquaculture products, among which, recreational value was about 189 million Yuan·a-1, and existence value was about 24 million Yuan·a-1. It was suggested that in the construction of new rural areas of Shanghai, sufficient attention should be paid on the full play of the cultural service value of aquaculture pond ecosystem.
    Wetland landscape ecological classification: Research progress.
    2009, 20(12):  3084-3092. 
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    Wetland landscape ecological classification, as a basis for the studies of wetland landscape ecology, directly affects the precision and effectiveness of wetland-related research. Based on the history, current status, and latest progress in the studies on the theories, indicators, and methods of wetland landscape classification, some scientific wetland classification systems, e.g., NWI, Ramsar, and HGM, were introduced and discussed in this paper. It was suggested that a comprehensive classification method based on HGM and on the integral consideration of wetlands spatial structure, ecological function, ecological process, topography, soil, vegetation, hydrology, and human disturbance intensity should be the major future direction in this research field. Furthermore, the integration of 3S technologies, quantitative mathematics, landscape modeling, knowledge engineering, and artificial intelligence to enhance the automatization and precision of wetland landscape ecological classification would be the key issues and difficult topics in the studies of wetland landscape ecological classification.
    Spatiotemporal variations of crop radiation use efficiency and harvest index: Research progress.
    2009, 20(12):  3093-3100. 
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    The radiation use efficiency (RUE) model suggested by Monteith in 1972 is one of the most widely applied approaches for modeling net primary production and crop yield, especially by means of remote sensing techniques. To use this approach, RUE and harvest index (HI) are the two key parameters that need to be defined, besides the absorbed photosynthetically active radiation. However, there exist some problems in the studies and applications of RUE and HI. This paper reviewed the research progress on RUE and HI, summarized the current methods and procedures for  defining RUE and HI values when using the RUE approach for predicting crop yield by remote sensing, and proposed that in order to maximize the effective application of RUE and HI in remote sensing crop yield and crop production management, future researches should seek proper procedures to determine the spatial heterogeneities of RUE and HI at regional scale based on field experiments.
    Research progress in water eco-functional regionalization.
    2009, 20(12):  3101-3108. 
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    Water eco-functional regionalization is a new zoning approach based on the study of regional differences in water ecosystem, aimed to reveal the spatial differentiation characteristics and distribution patterns of water environment at different regional and zonal scales. This paper discussed the methodologies, objectives, and limitations of water function zoning, water environmental function zoning, geoecology zoning, ecoregion classification, and water eco-functional regionalization, summarized the research progress in the water eco-functional regionalization, and compared the regionalization system at home and abroad. The disadvantages of our water eco-functional regionalization system were pointed out, and its development trend was prospected.
    Effects of grape-replanting on soil bacterial and fungal populations.
    2009, 20(12):  3109-3114. 
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    Rhizosphere and non-rhizosphere soil samples were collected from the vineyards having been planted for 3 and 30 years, and PCR-DGGE technique was adopted to study the effects of grape-replanting on the population structure and diversity of soil bacteria and fungi. The bacterial and fungal diversities were higher in 30-year-planted vineyard than in 3-year-planted vineyard, and higher in rhizosphere soil than in non-rhizosphere soil. After 30 years replanting, the population structure of bacteria and fungi approached the same in rhizosphere soil and non-rhizosphere soil but differed from that in fallow soil; while in the 3-year-planted vineyard, the population structure in rhizosphere soil was different from that in non-rhizosphere soil and fallow soil. Comparing with that in 3-year-planted vineyard, the rhizosphere soil microbial population in 30-year-planted vineyard had a greater change. In bacterial population, Flavobacterium sp.(DQ339585) and Bacillus sp.(AY039821) decreased while Pedobacter sp. (AJ871084) increased; in fungal population, Omphalina farinolens (EF413029) appeared, Pestalotiopsis sp.(DQ657877, DQ657875, DQ657871), Phacidium lacerum (DQ470976), and Lecythophora decumbens (AF353597) decreased, while Pilidium acerinum voucher (AY48709) increased. acillus sp., Flavobacterium sp., and Pestalotiopsis sp. had antagonism to pathogen, and their decrease reduced the resistance of grape against pathogen. The increase of Pilidium acerinum voucher might relate to the severe disease after grape- replanting.