Table of Content

18 August 2006, Volume 17 Issue 08

Previous Issue    Next Issue

Articles

Effects of disturbances on plant species diversity of secondary forest in montane regions of eastern Liaoning Province

MAO Zhihong^1,2; ZHU Jiaojun¹; TAN Hui^1,2

2006, 17(08):  1357-1364 . 

Asbtract ( 2374 )   PDF (2602KB) ( 1259 )  

According to the distance from forest stands to residential area and the first and second grade roads, as well as the canopy density and the percentage of damaged trees, this paper defined the disturbances, anthropogenic and natural, as low, medium and high levels. On the basis of this, the effects of different level disturbances on the plant species diversity of secondary forest in montane regions of eastern Liaoning Province were analyzed, and the differences between the effects of anthropogenic and natural disturbances were discussed. The results showed that without considering forest types, the overall plant species diversity of secondary forest under medium level anthropogenic disturbance was higher than that under low and high level anthropogenic disturbances, with the Simpson indexes being 096, 095 and 092, and ShannonWiener indexes being 377, 360 and 336, respectively. The diversities of shrub and herb layers were also the highest under medium level anthropogenic disturbance, while the highest diversity of arbor layer was appeared under the high level one. Among different forest types, there existed differences in the plant species diversity under anthropogenic disturbances, e.g., the diversity under medium level anthropogenic disturbance was the lowest in hard broadleaved forests, but the highest in other forest types. In all test forest types, no consistent tendency was observed in the changes of three layers’ diversities with anthropogenic disturbance levels, but the diversities of shrub and herb layers were greatly affected by the disturbances. After 3 years of snow/wind damage, there was no distinct difference in the diversities among the birch forests under low, medium and high level natural disturbances, with the Simpson indexes being 0.91, 0.91 and 0.92, and the Shannon-Wiener indexes being 2.30, 2.93 and 2.89, respectively. The diversities of arbor and shrub layers were both increased with the enhancement of natural disturbances, but there was no great difference in the diversity of herb layer among the three levels of natural disturbances. At present, anthropogenic disturbance mostly occurred in understory, while snow/wind damage occurred in canopy. Such dissimilarity could make the effects of environmental factors on plant species diversity differed greatly.

Regeneration of Acacia glauca and Leucaena leucacephala plantations in Yuanmou dry and hot valley

MA Jiangming^1,2; LI Kun¹; ZHANG Changshun¹

2006, 17(08):  1365-1369 . 

Asbtract ( 2343 )   PDF (523KB) ( 1122 )  

An investigation on the seed yield, seed dispersal pattern, seed density, and the numbers of seedlings and saplings was conducted at the sampling sites of Acacia glauca and Leucaena leucacephala plantations. The factors affecting the natural regeneration and tree adaptability of A. glauca and L.leucacephalawere analyzed, and their regeneration status was evaluated by gray relational analysis. The results showed that the seed yield of A. glauca with the same age was 566 grains per tree, while that of L.leucacephala was 1 199 grains per tree. The mean seed yield of individual tree, whether A. glauca or L. leucacephala, was higher in mixed forest than in pure forest, and that of naturally regenerated L. leucacephala forest was between those of A. glauca and L. leucacephala plantations. With the increasing distance to mother tree, A. glauca had a smaller decrement of seed density than L. leucacephala. The seed dispersal distance of A. glauca was 110 m, while that of L. leucacephala was 90 m. The gray relational coefficient of A. glauca plantation, L. leucacephala plantation, and naturally regenerated L. leucacephala forest was 0.7269, 0.6000 and 0.6000, respectively, indicating that A. glauca plantation had a better regeneration status.

Root decomposition and nutrient release of Fraxinus manshurica and Larix gmelinii plantations

ZHANG Xiujuan^1,2; WU Chu²; MEI Li¹; HAN Youzhi^1,3; WANG Zhengquan¹

2006, 17(08):  1370-1376 . 

Asbtract ( 2196 )   PDF (511KB) ( 1210 )  

A two-year buried bag experiment with different sizes of Fraxinus mandshurica and Larix gmelinii roots showed that the coarse (5～10 mm), medium (2～5 mm) and fine (＜2 mm) roots of F. mandshurica had an annual decomposition coefficient of 0.3649, 0.4381 and 0.2720, while those of L. gmelinii had the coefficient of 0.1967, 0.1955 and 0.2464, respectively. During root decomposition, large amounts of carbon and nutrients released. After buried into soil for 150 days, more than 90% of soluble sugar in all sizes of the two species roots was released, and about 40%, 71% and 95% of potassium was released from the coarse and medium, and fine roots of F. mandshurica, and all sizes of L. gmelinii roots, respectively. In the second year of the experiment, about 50% of nitrogen and 40% of phosphorus were released from the coarse and medium roots of the two species, and 60% of nitrogen and phosphorus were released from their fine roots. In the study of forest ecosystem’s carbon and nutrient cycles, root decomposition shouldn’t be ignored.

Rhizosphere effects of Pinus sylvestris var. mongolica on soil phosphorus transformation

ZHAO Qiong^1,2; ZENG Dehui¹; YU Zhanyuan^1,2; DENG Bin^1,2; FAN Zhiping¹

2006, 17(08):  1377-1381 . 

Asbtract ( 2597 )   PDF (988KB) ( 1017 )  

To understand the phosphorus (P) mobilization mechanism of Mongolian pine (Pinus sylvestrisvar. mongolica) on a Pdeficient semiarid sandy soil of northern China, this paper compared the P fractions and acid phosphomonoesterase (AP) activity in the bulk and rhizosphere soils under different age Mongolian pine plantations. The results showed that when compared with the bulk soil, the organic C, labile organic P, and organic C/P ratio increased significantly, microbial and AP activities improved, and organic P mineralization accelerated in the rhizosphere soil. Root activity of the Mongolian pine significantly increased the bioavailability of soil P, and accelerated the shift of organic P and Ca-P to Fe-P and Al-P. The rhizosphere effects on soil P in different forms enhanced with stand age, whereas in adverse on AP activity. The bulk and rhizosphere soil had the similar trend in the dynamics of its P fractions with stand age. Soil total P pool reduced gradually while labile P pool increased with stand age. It should be essential to protect forest floor to replenish soil P pool and guarantee a longterm soil P supply.

Aboveground biomass of three conifers in Qianyanzhou plantation

LI Xuanran^1,2,3; LIU Qijing¹; CHEN Yongrui¹; HU Lile⁴; YANG Fengting¹

2006, 17(08):  1382-1388 . 

Asbtract ( 2636 )   PDF (554KB) ( 1210 )  

In this paper, the regressive models of the aboveground biomass of Pinus elliottii, P. massoniana and Cunninghamia lanceolata in Qianyanzhou of subtropical China were established, and the regression analysis on the dry weight of leaf biomass and total biomass against branch diameter (d), branch length (L), d³ and d²L was conducted with linear, power and exponent functions. Power equation with single parameter (d) was proved to be better than the rests for P. massoniana and C. lanceolata, and linear equation with parameter (d³) was better for P. elliottii. The canopy biomass was derived by the regression equations for all branches. These equations were also used to fit the relationships of total tree biomass, branch biomass and foliage biomass with tree diameter at breast height (D), tree height (H), D³ and D²H, respectively.D²H was found to be the best parameter for estimating total biomass. For foliageand branch biomass, both parameters and equation forms showed some differences among species. Correlations were highly significant (P＜0.001) for foliage-, branch-and total biomass, with the highest for total biomass. By these equations, the aboveground biomass and its allocation were estimated, with the aboveground biomass of P. massoniana, P. elliottii, and C. lanceolata forests being 83.6, 72.1 and 59 t·hm^-2, respectively, and more stem biomass than foliageand branch biomass. According to the previous studies, the underground biomass of these three forests was estimated to be 10.44, 9.42 and 11.48 t·hm^-2, and the amount of fixed carbon was 47.94, 45.14 and 37.52 t·hm^-2, respectively.

Cold hardiness of Pinus ponderosa, P. banksian and P. tabulaeformis

GONG Yuehua¹; ZHOU Yongxue²; FAN Junfeng²; LIU Yingzhou¹; PANG Kejia¹ 

2006, 17(08):  1389-1392 . 

Asbtract ( 2578 )   PDF (445KB) ( 1167 )  

By the method of artificial freezing, this paper made a comparative study on the cold hardiness of Pinus ponderosa, P. banksiana and P. tabulaeformis, with their inherent mechanisms approached. The results showed that the cold hardiness of these three species was in the sequence of P. banksiana＞P. tabulaeformis＞P. ponderosa. P. banksiana had high bound water/free water ratio (7.0) and ABA content (164.3 μg·g^-1 FW) but low K⁺ (2 450 μg·g^-1 DW) and soluble sugar (12.0%), P. tabulaeformis had higher contents of ABA (95.8 μg·g^-1 FW), K⁺ (4 538 μg·g^-1 DW) and soluble sugar (18.68%) but low bound water/free water ratio (2.58), while P. ponderosa had high soluble sugar content (18.05%) but low bound water/free water ratio (2.18) and K⁺ (2 275 μg·g^-1 DW) and ABA (63.3 μg·g^-1 FW) contents. These differences might be the reasons resulting in the different cold hardiness of these three species. Low chlorophyll content and high carotenoid/chlorophyll ratio might also contribute to the cold hardiness of P. banksiana. Therefore, though the test species are all of cold hardiness, their inherent mechanisms may be different.

Seasonal changes in foliar micro-and ultra structure of two Sabina species and their relationships with cold tolerance

ZHANG Youfu¹; CHEN Yinping^2,3; ZHANG Manxiao^1,4; CHEN Tuo¹; AN Lizhe^1,2

2006, 17(08):  1393-1397 . 

Asbtract ( 2227 )   PDF (1338KB) ( 1063 )  

In this paper, the foliar micro-and ultra structure of Sabina przewalskii and S. chinensis during growth and dormancy seasons was observed under microscope and transmission electron microscope, and the foliar soluble sugar content was measured, aimed to probe into their relationships with cold tolerance. The results showed that the foliar surface cells of these two Sabina species were covered with thick cuticular membrane, and the welldeveloped arenchyma appeared in the mesophyll. In growth season, starch grains accumulated in chloroplasts, but in dormancy season, the accumulated starch grains disappeared or diminished, while soluble sugar content had a larger increase. In wintertime, the chloroplasts of S. chinensis were injured, with some abnormal chloroplasts, increased plastoglobuli and some lipid drops, while those of S. przewalskii were not obviously injured. It was suggested that the cold tolerance of the two Sabina species was related to their well-developed arenchyma, accumulation of starch grains in growth season, and increase of soluble sugar content in dormancy season. S. przewalskii had more marked increase of soluble sugar content, and its chloroplasts were more stable than S. chinensis.

Effects of bryophytes in dark coniferous forest of Changbai Mountains on three conifers seed germination and seedling growth

LIN Fei^1,2; HAO Zhanqing¹; YE Ji¹; JIANG Ping¹

2006, 17(08):  1398-1402 . 

Asbtract ( 2462 )   PDF (974KB) ( 1071 )  

This paper studied the effects of Hylocomium splendens and Rhytidiadelphus triquetrus, the main bryophytes in dark coniferous forests of Changbai Mountains, on the seed germination and seedling growth of Pinus koraiensis, Picea koraiensis and Larix olgensis. The results indicated that at definite concentrations, the water extract of H. splendens inhibited Picea koraiensis seed germination, while that of R. triquetrus promoted it. Although the water extracts of the two bryophytes had no obvious effects on the seed germination of Picea koraiensis and Larix olgensis, they expedited the occurrence of the tree species’daily germination peak. The water extracts of test bryophytes inhibited the seedling growth of P. koraiensis and Picea koraiensis, but promoted that of Larix olgensis. The living shoots of the two bryophytes had no obvious effects on the seed germination of Picea koraiensis and Larix olgensis, but delayed the daily germination peak of Picea koraiensis while promoted that of Larix olgensis, and the killed shoots inhibited the seed germination of all test tree species. Living shoots in larger amounts promoted the seedling growth of Picea koraiensis and Larix olgensis, but killed shoots were in adverse.

Estimation of rainfall interception by broadleaved Korean pine forest in Changbai Mountains

WANG Anzhi; PEI Tiefan; JIN Changjie; GUAN Dexin

2006, 17(08):  1403-1407 . 

Asbtract ( 2150 )   PDF (1626KB) ( 1066 )  

Rainfall interception by forest canopy is an important process of water resources cycle in forest watershed. Most studies focused on the relationships of the interception with the precipitation in one or more rainfall events, without considering rainfall density and vegetation characteristics. By using a semi-theoretical model of canopy rainfall interception model, taking rainfall intensity and leaf area indices as inputs and canopy wetness index as parameter, and combining with Penman-Monteith equation, this paper simulated the rainfall interception by the broad-leaved Korean pine forest canopy in Changbai Mountains, and estimated the total interception of rainfall events from 1 May to 30 September 2004. The results showed that the total interception was 39.96 mm, occupying 10.2% of the precipitation, and the estimated results agreed well with the measured ones. Based on the estimated results, the relationships between interception and rainfall on different temporal scales were analyzed, which suggested that with the increase of temporal scale from 30 min to a month, the correlation between interception and rainfall became more and more obvious.

Forest distribution pattern and land use strategy along urban-rural gradient

DONG Yibo; LIU Maosong; XU Chi; ZHANG Cheng; LIU Zhibin

2006, 17(08):  1408-1412 . 

Asbtract ( 2364 )   PDF (1355KB) ( 1101 )  

According to the buffers and urban fringes of Nanjing in 1988 and 2003, and by using landsat TM images and DEM data, 8 urban-rural gradient zones called Ⅰ,Ⅱ,Ⅲ， … …， Ⅷ in this city were marked off, and the forest distribution pattern as well as the land use strategies along these gradient zones were studied. The results showed that in each of these zones, there was a significant positive correlation between the coverage of mountainous area and forest, and the forest coverages were obviously higher in mountainous than in flat area, with a distribution pattern of Ⅰ＞Ⅱ，Ⅱ＜Ⅲ,Ⅲ≈Ⅳ,Ⅳ＞Ⅴ＞Ⅵ＞Ⅶ＞Ⅷ. In urbanizing area, there were three major land use types, i.e., urban building, ecological regulation (mainly forest stand), and agricultural production (mainly crop land). The potential value of a certain land use type became the leading cause of land use type selection. Inner city area had very low forest coverage because of its high exploitation value, and the ecological value of the outskirts within 10 km beyond the urban fringe was comparatively outstanding, with the forest coverage increased significantly. The forest coverage declined with the increasing distance to urban, because of the dominant station of the production value.

Effects of light and matrix on turion germination, seedling growth and leaf photosynthesis efficiency of Potamogeton crispus

CHEN Xiaofeng¹; CHEN Kaining²; XIAO Yue’e¹; ZHANG Shoudong¹; WANG Qingya¹

2006, 17(08):  1413-1418 . 

Asbtract ( 2594 )   PDF (1264KB) ( 1226 )  

The study with in-door experiment showed that the germination and seedling rates of Potamogeton crispus were increased under light but without matrix. Matrix promoted root growth, but light could not. The internode’s length was obviously longer under dark than under light. After treated with dark, the permeability of leaf plasma membrane raised apparently. Under light condition, the Chla and Chlb contents and Chla/Chlb ratio of seedling’s leaf fluctuated, depending on with or without matrix. The maximum and minimum value of Chla/Chlb ratio was 4.4 and 2.8, respectively when the matrix existed, and was 4.2 and 2.7 when the matrix was absent. After 40 days of seedling growth, there was a significant difference in the permeability of leaf plasma membrane between the treatments with light and matrix, and with light but without matrix (P＜0.01). A significant difference was also observed in F_v/F_m, and F_v/F_o at the late growth period between the treatments of full (100%) and partial (50%, 20% and 10%) natural light, while no significant difference was found between the treatments of different partial natural light. It was suggested from the measurements of F_v/F_m, F_v/F_o, ETR, qP and qN that weak light promoted the photosynthesis, and slowed down the senile of P. crispus.

Growth patterns of Leymus chinensis clones under different habitat conditions in Songnen Plain of China

YANG Yunfei; ZHANG Baotian

2006, 17(08):  1419-1423 . 

Asbtract ( 2263 )   PDF (869KB) ( 1120 )  

A tracking investigation was conducted in the Songnen Plain of China on the experimental clones of Leymus chinensis under cultivation, and the natural clones of this grass in the succession process of vegetation restoration after meadow flooding. The results showed that on aeolian sandy soil where existed enough growth space but no interspecific competition, there was a month interval between the transplanting of two experimental clones, and the sizes of these clones had a one-fold difference by the end of next growth season. During the whole growth season, the vegetative reproduction of the two experimental clones followed the same exponential pattern. After 6 years restoration succession on flooded meadow, the vegetative reproduction of clonal populations in L. chinensis + Carex duriuscula and L. chinensis + weed communities were all accorded with power function. On flooded alkaline meadow where existed interspecific competition, the natural clones could still increase their offspring numbers exponentially, and quickly expand their niche space at the same time.

Effects of CaCO₃ addition under Zn supply on wheat seedlings growth and Zn uptake

LU Xinchun; CHEN Ling; TIAN Xiaohong; MAI Wenxuan; LI Shengxiu

2006, 17(08):  1424-1428 . 

Asbtract ( 2286 )   PDF (779KB) ( 1071 )  

High concentration calcium carbonate in calcareous soils usually limits plant Zn uptake. In this paper, a solution culture experiment was conducted to study the effects of CaCO₃ addition with or no Zn supply on the growth and Zn uptake of three genotypes winter wheat seedlings. The results showed that Zn supply or CaCO₃ addition had no significant effects on seedlings biomass and root/canopy ratio, and there was no significant difference among the three genotypes. CaCO₃ addition led to leaf chlorosis. No matter with or no Zn supply, CaCO₃ addition had no significant effects on the Zn concentration and accumulation in wheat root, stem, and leaf. Zn supply increased the Zn concentration in Yuanfeng 998, Zhongyu 6, and Xiaoyan 22 by 80.0%, 104.8% and 139.6%, respectively. For Yuanfeng 998, a sensitive genotype to Zn-deficiency, the increment of Zn concentration and accumulation was much lower than that of Zhongyu 6 and Xiaoyan 22, non-sensitive genotypes to Zn-deficiency. Zn supply or CaCO₃ addition had no significant effects on the P content in root, stem, and leaf, but the corresponding P content of Yuanfeng 998 was obviously lower than that of the other two genotypes. Zn supply greatly decreased the P/Zn ratio in root, stem and leaf, and CaCO₃ addition also showed the same tendency. Under Zn-deficiency, CaCO₃ addition caused leaf chlorosis, but did not decrease wheat plant Zn uptake. In conclusion, at least under solution culture condition, high concentration calcium carbonate had no obvious inhibitory effect on plant zinc uptake, and whether this situation was true in calcareous soils is worthy to be further investigated.

Physical and chemical properties of soil bio-crust on rehabilitated grassland in hilly Loess Plateau of China

ZHAO Yunge^1,2; XU Mingxiang^1,2; WANG Quanjiu^1,2; SHAO Ming’an^1,3

2006, 17(08):  1429-1434 . 

Asbtract ( 2511 )   PDF (836KB) ( 1078 )  

Soil bio-crust (SBC) plays an important role in degraded ecosystem restoration. The field investigation and laboratory analysis of SBC on different year rehabilitated grasslands at the north slope of hilly Loess Plateau showed that after cropland shifted to rehabilitated grassland, rainfall induced structural crust appeared firstly, and then, with the increasing year of rehabilitation, crust-forming microorganism gradually settled in, and SBC developed. The depth of SBC increased in inverse “S” shape with increasing year of rehabilitation. 10 years after rehabilitation, the increase of SBC depth slowed down, and soil bulk density decreased from 1.4 g·cm^-3 to 1.1 g·cm^-3. SBC formation improved soil cohesion significantly, and the latter was increased in inverse “S” shape with increasing year of rehabilitation. The organic matter and total nitrogen contents in SBC were obviously higher than those in cropland, and increased gradually with increasing year of rehabilitation but tended to be stable after 10 years of rehabilitation. The available N, P and K contents in SBC were also increased, but no significant difference of total phosphorus was found between SBC and cropland soil. The formation of SBC in test region could be classified into 3 stages, i.e., the first stage named the beginning of the formation, which was from 1 to 4 years of grassland rehabilitation, the second stage named the rapid development period, which was from 5 to 10 years of the rehabilitation, and the third stage named stable period after 10 years of rehabilitation.

Evapotranspiration of winter wheat field on Loess Plateau tableland

GAN Zhuoting^1,2; LIU Wenzhao^1,3

2006, 17(08):  1435-1438 . 

Asbtract ( 2158 )   PDF (1155KB) ( 1183 )  

This paper measured the evapotranspiration (ET) rate of a winter wheat field on the Loess Plateau tableland by using large-scale weighing lysimeter, and analyzed the effects of wheat leaf area index (LAI), soil water content, air temperature, and rainfall on the ET at the time scales of growth stage, month, day, and hour. The results showed that the mean daily ET rate in different growth stages was in the order of bootingheading﹥flowering﹥erecting﹥jointing﹥filling﹥reviving﹥ripening﹥overwintering. Air temperature had a larger effect in initial stage, LAI was in mid stage, and soil water content was in last stage in the experimental year. The mean daily ET rate was markedly decreased from 6.25 mm·d^-1 at bootingheading stage to 2.66 mm·d^-1 at grain-filling stage due to soil water deficit. The monthly ET rate in April, May and June was higher than that in other months, and the ET amount of the three months accounted for 80% of the total during the experimental period. The apices of daily ET curve mainly reflected the effects of rainfall, and the hourly ET process basically reflected the ET changes with weather conditions.

Photosynthetic characteristics of grapevine varieties with different ecological adaptabilities grown in a rain-shelter plastic greenhouse in the Yangtze River Delta region

JIANG Weibing¹; DAI Meisong^1,3; ZHUANG Meng¹; FEI Xianjin²

2006, 17(08):  1439-1442 . 

Asbtract ( 2344 )   PDF (737KB) ( 1061 )  

The study with two grapevine varieties Manicure Finger and Fujiminori grown in a rain-shelter plastic greenhouse in the Yangtze River Delta region showed that in the greenhouse, the photon flux density (PFD) decreased greatly, while air temperature (T_a), vapor pressure (V_p) and transpiration rate (T_r) had little changes, no matter in sunny or cloudy days. The leaf thickness and fresh weight per cm² of the two varieties decreased by 28.6% and 18.4%, and 13.1% and 11.6%, respectively, total chlorophyll content and apparent quantum yield (AQY) had a slight increase, but chlorophyll a and b contents and chlorophyll a/b ratio had no obvious difference with the open-air cultivation (CK). In sunny days, the diurnal mean value of net photosynthetic rate P_n, diurnal integral value of P_n, and water use efficiency (WUE) of Manicure Finger and Fujiminori decreased by 18.7% and 13.1%, 17.2% and 11.9%, and 26.0% and 36.9%, but stomatal conductance (G_s) increased by 76.8% and 100.8%, respectively, while in cloudy days, the corresponding values of abovementioned parameters were decreased by 48.7% and 33.5%, 34.0% and 29.8%, and 69.2% and 67.7%, and increased by 178.0% and 85.1%, respectively. The variation extents of the parameters were larger for Manicure Finger than for Fujiminori, especially in cloudy days, indicating the great differences of ecological adaptability between these two grapevine varieties.

Quantitative relationships between leaf area index and canopy reflectance spectra of wheat

LI Yingxue; ZHU Yan; DAI Tingbo; TIAN Yongchao; CAO Weixing

2006, 17(08):  1443-1447 . 

Asbtract ( 2402 )   PDF (1801KB) ( 1096 )  

Based on the change patterns of leaf area index (LAI) and canopy spectral reflectance of wheat at different growth stages and nitrogen application rates, this paper investigated the relationships of LAI with canopy reflectance and spectral parameters, and brought forward the sensitive spectral parameters and quantitative equation for predicting wheat LAI. The results showed that with increasing nitrogen application rate, wheat LAI and its canopy reflectance at near infrared (760～1 220 nm) increased, whereas the reflectance at visible band (460～710 nm) decreased. From jointing to maturity, the LAI and the reflectance of short bands in near infrared increased initially and decreased then, whereas the reflectance of visible light and long bands in near infrared was in adverse, with the lowest value appeared at booting stage. Wheat LAI was negatively correlated with the reflectance of visible light, but positively with that of short bands in near infrared, with the highest correlation coefficient at 810 nm. It was proposed that wheat LAI could be well monitored by vegetation indices RVI (810, 510) and DVI (810, 560). PVI and TSAVI were proved to be the spectral indices in monitoring wheat LAI, and higher accuracy was obtained with combined RVI (810, 510), DVI (810, 560) and PVI.

Dynamic model of rice tiller in FACE

SUN Chengming¹; ZHUANG Hengyang¹; YANG Lianxin¹; YANG Hongjian¹; HUANG Jianye¹; DONG Guichun¹; ZHU Jianguo²; WANG Yulong¹

2006, 17(08):  1448-1452 . 

Asbtract ( 2502 )   PDF (1220KB) ( 1072 )  

With Japonica cultivar Wuxiangjing 14 as test material, a free-air CO₂ enrichment (FACE) experiment was conducted at Anzhen and Wuxi of Jiangsu Province in 2001～2003. The target CO₂ concentration of FACE plots was 570 μmol·mol^-1, 200 μmol·mol^-1 higher than that of ambient air. Three levels of N were supplied as LN (150 kg·hm^-2), MN (250 kg·hm^-2) and HN (350 kg·hm^-2). The effects of FACE treatment on the dynamics of rice tiller was studied, and the simulation model was established as T_t=A₁(1+e^a1-b1t₎-A₂(1+e^a2-b2t)+C×[B₁(1+e^a3-b3t)-B₂(1+e^a4-b4t)]+D. Where T_t was the numbers of rice tiller in t days after transplanting; A₁ and A₂ were the maximal tillers of production and death under ambient air, respectively; B₁ and B₂ were the maximal potential tillers of production and death under FACE, respectively; C was the coefficient of CO₂ concentration; D was the initial tillers after transplanting; and a₁, a₂, a₃, a₄, b₁, b₂, b₃ and b₄ were the control coefficients of the model. The dynamics of tiller numbers with the days after transplanting was described, and the model fitted well under ambient air and FACE conditions. Through testing with different year experimental data, the maximum and minimum RMSE was forecasted as 44.27 and 13.96 ind·m^-2, respectively, suggesting that the model was accurate and applicable.

Estimation models of rice LAI and Chlorophyll content based on MOD09

CHENG Qian

2006, 17(08):  1453-1458 . 

Asbtract ( 2538 )   PDF (1010KB) ( 1110 )  

The MODIS (moderate-resolution imaging spectroradiometer) surface reflectance product MOD09, which was strictly corrected by NASA, can be widely applied to monitor the change of land vegetation. In this paper, a quasi and synchronous experiment of MODIS sensor was performed, and the rice leaf area index (LAI) and chlorophyll content (Chltot) were measured. The relationships between the vegetation indices (VIs) derived from MOD09 and the rice LAI and Chltot were analyzed, and the estimation models were established. The VIs values derived from MOD09 were higher than those in the first three bands of MOD09, and EVI value was lower than NDVI value. In comparing with other Vis, EVI had a better relationship with LAI at different rice growth stages. MOD09-EVI was selected to construct the estimation model of rice LAI, and validated by other in situ sampling plot data to be more precise, suggesting MOD09-EVI was the best index to monitor rice LAI. There was a significant correlation between MOD09-Red band and Chltot at early and medium rice growth stages. The estimation model of rice canopy Chltot based on MOD09-Red band was established and validated, and no models were significantly efficient, except the estimation model of Chltot at booting stage.

enetic diversity of indigenous sheep breeds in Shandong Province based on microsatellite markers study

YUAN Cunzhong¹; WANG Jianmin¹; MA Yuehui²; QU Xuxian³; SHANG Youguo¹; ZHANG Ningbo¹

2006, 17(08):  1459-1464 . 

Asbtract ( 2308 )   PDF (472KB) ( 1184 )  

By using 24 microsatellite markers, this paper studied the genetic diversity of four indigenous sheep breeds in Shandong Province. 467 alleles were detected from 164 sheep of 71 breeding groups, and the proportion of effective alleles was 49.59%. The differences of the allele number among microsatellite loci were larger than those among breeds. 123 peculiar alleles and 43 dominative alleles were found from these sheep 89% of the microsatellite markers were not in Hardy-Weinberg, and 50% of them were neutral. All the microsattelite markers were of high polymorphic (PIC＞0.5), and the values of Shannon indexes were relatively high. The observed heterozygosities (0.454~0.560) were significantly lower than their expected values (0.831~0.849). It was suggested that the four indigenous sheep breeds in Shandong Province were highly genetic polymorphic but somewhat inbred. The NJ and UPGRAM dendrograms indicated that the small-tailed and large-tailed Han sheep in west Shandong were closer in genetics, and the Shandi and Wadi sheep in east Shandong were similar. The genetic distances between different sheep breeds were accordant to geographical distances.

Relationships of bee population fluctuation and distribution with natural environment in Anhui Province

YU Linsheng; ZOU Yunding; BI Shoudong; WU Houzhang; CAO Yifeng

2006, 17(08):  1465-1468 . 

Asbtract ( 2297 )   PDF (742KB) ( 1080 )  

In 2002～2004, an investigation was made on the bee population dynamics and its relationships with the ecological environment in four ecological regions of Anhui Province. The results indicated that in the mountainous areas of south and west Anhui, there were 46 and 37 species of nectariferous plants, and the distribution density of Apis cerena cerena population was 2.01 and 1.95 colony·km^-2, respectively. In Jianghuai area and Huaibei plain, there were 17 and 12 species of nectariferous plants, which had concentrated and short flowering period and fitted for Apis mellifera Ligustica oysterring and producing, and the distribution density of Apis cerena cerena population was 0.06 and 0.02 colony·km^-2, respectively. Bee population fluctuation and distribution was affected by wasp predation. The breeding proportion of Apis cerena cerena to local apis population was 41.5%, 36.8%, 3.1% and 1.1%, and that of Apis mellifera Ligustica was 58.5%, 63.2%, 96.9% and 98.9% in the mountainous areas of south and west Anhui, Jianghuai area, and Huaibei plain, respectively.

Responses of Artemisia ordosica population to soil moisture spatial heterogeneity on semi-fixed dune of Mu Us sandy land

LU Jianguo; WANG Haitao; HE Xingdong; GAO Yubao

2006, 17(08):  1469-1474 . 

Asbtract ( 2351 )   PDF (2436KB) ( 1127 )  

Spatial heterogeneity affects the functions and processes of ecosystems. By the methods of statistics and geostatistics, this paper approached the relationships between the spatial heterogeneities of Artemisia ordosica and soil moisture on the semi-fixed dune of Mu Us sandy land. The results showed that on plot-scale (80 m×80 m), the spatial heterogeneity of A. ordosica biomass and density was dependant on that of soil moisture, and in particular, there existed a significant positive correlation between the biomass and the moisture, indicating that on semifixed dune, soil moisture played a decisive role in the spatial heterogeneity of plant population. Due to the redistribution of precipitation on sand dune, the outcomes of the interactions between the spatial heterogeneities of soil moisture and A. ordosica population were assumed as patchness of terrain→ patchness of soil moisture distribution→ patchness of A. ordosica population distribution→ patchness of A. ordosica biomass and density.

Evaluation of eco-environmental quality based on artificial neural network and remote sensing techniques

LI Hongyi¹; SHI Zhou¹; SHA Jinming²; CHENG Jieliang¹

2006, 17(08):  1475-1480 . 

Asbtract ( 2498 )   PDF (1767KB) ( 1179 )  

In the present study, vegetation, soil brightness, and moisture indices were extracted from Landsat ETM remote sensing image, heat indices were extracted from MODIS land surface temperature product, and climate index and other auxiliary geographical information were selected as the input of neural network. The remote sensing eco-environmental background value of standard interest region evaluated in situ was selected as the output of neural network, and the back propagation (BP) neural network prediction model containing three layers was designed. The network was trained, and the remote sensing eco-environmental background value of Fuzhou in China was predicted by using software MATLAB. The class mapping of remote sensing eco-environmental background values based on evaluation standard showed that the total classification accuracy was 87.8%. The method with a scheme of prediction first and classification then could provide acceptable results in accord with the regional eco-environment types.

Eco-environmental evaluation and spatial-temporal collocation of regional land consolidation

WANG Ailing^1_; ZHAO Gengxing¹; WANG Ruiyan¹; YUAN Xiangming²

2006, 17(08):  1481-1484 . 

Asbtract ( 2415 )   PDF (568KB) ( 1144 )  

Eco-environmental evaluation and spatial-temporal collocation of land consolidation is the basis of regional land consolidation. Taking Qingzhou County of Shandong Province as an example, this paper established the eco-environmental evaluation index system and evaluation model of land consolidation, based on the systematic analysis of land consolidation characteristics and natural and social conditions of Qingzhou County. The comprehensive score of each evaluation unit was obtained by integrated index evaluation method and GIS techniques, and the spatial-temporal collocation of regional land consolidation was proposed accordingly. The results indicated that in Qingzhou County, the total area of cultivated and un-utilized land was 1 446 km², among which, the land consolidation area in near future mainly distributed in the northwest part of plain region, occupying 15.35% of the total, mid-phase land consolidation area mainly distributed in the northwest and central parts of plain region, occupying 13.58%, land consolidation area in specified future mainly distributed in the north part of plain region, occupying 40.71%, and non-land consolidation area mainly distributed in hilly region, occupying 30.36%. These results could provide scientific instruction for the land consolidation planning and implement in Qingzhou County.

Responses of regional ecological service value to land use change: A case study of Shapingba County in Chongqing

WANG Cheng¹; WEI Chaofu¹; SHAO Jing’an¹; GAO Ming¹; JIANG Wei²

2006, 17(08):  1485-1489 . 

Asbtract ( 2411 )   PDF (1050KB) ( 1096 )  

Land use has significant effects on the products and services provided by ecosystem, through its interaction with ecosystem processes and services. Taking Shapingba County in Chongqing as an example, and by the Costanza method and ecological sensitivity analysis, this paper analyzed the effects of land use change on ecological service value. The results indicated that from 1992 to 2002, the ecological service value of this County was from ＄ 1.74×10⁷ to ＄16.8×10⁷, i.e.,＄ 0.54×10⁵ was lost. Accordingly, each hectare land suffered an average loss of ＄13.62. The ecological service value coefficient assigned to different categories of land use had little effects on the total ecological service value, and the total change of ecological service value was inelastic. The summation of the ecological service value coefficients assigned to cultivated land, forestland and garden land was very close to regional actualities. But, the ecological service value coefficient assigned to the waters was higher than the actual value, while rectifying 30 percent of the previous coefficient by 5 667 ＄·hm^-2·yr^-1 would be very close to the actual one. Applying Costanza method to estimate the change of regional ecological service value was practicable, and would make a reference for the evaluation of land use benefits and the organization of land use planning.

Heavy metals contents in Haplocladium and their relationships with Shanghai City environment

AN Li; CAO Tong; YU Yinghao

2006, 17(08):  1490-1494 . 

Asbtract ( 2237 )   PDF (531KB) ( 1101 )  

This paper measured the Cu, Pb, Cd, Zn and Cr contents in Haplocladium plants and corresponding soils at 13 monitoring sites of Shanghai City, and analyzed the relationships between plant heavy metals contents and environment. The results indicated that these 13 monitoring sites could be divided into three groups of different degree heavy metals pollution, i.e., 1) seriously polluted, including Guilin, Guangqi, and Fuxing Park near the most heavy-traffic areas with intense pollution and disturbance, and the plant pollutants contents (mg·kg^-1) being Cu 35.25～50.36, Pb 55.50～65.00, Cd 1.68～2.3, Zn 829.63～1 140.13, and Cr 7.41～16.41, 2) polluted, including Changfeng, Guzhong, Zhongshan, and Heping Park as well as the campus of Shanghai Normal University at Xuhui District in the outskirts with less heavy metals pollution, and the plant pollutants contents (mg·kg^-1) being Cu 18.51～62.50, Pb 14.38～34.25, Cd 0.81～1.40, Zn 354.25～671.75, and Cr 3.62～25.08, and 3) basically unpolluted, including Sheshan Mt., Shanghai Botanic Garden, Chongming National Forest Park, Daguanyuan Park, and Luojing at the suburbs of Shanghai City, with the plant pollutants contents (mg·kg^-1) being Cu 11.13～16.41, Pb 4.63～27.25, Cd 0.93～1.28, Zn 489.25～1 086.75, and Cr 1.53～7.62. The heavy metals contents in Haplocladium plants had some correlations with corresponding soils, and there were some other factors besides soil affecting the heavy metals contents in Haplocladium plants. It was suggested that bryophytes as biological indicators could be used to indicate the heavy metals pollution in Shanghai City.

Spatial variability of farmland heavy metals contents in Qianan City

WANG Bo¹; WANG Yuanzhong²; LI Dongmei²; GAO Yunfeng²; Mao Renzhao¹

2006, 17(08):  1495-1500 . 

Asbtract ( 2176 )   PDF (1738KB) ( 1148 )  

By the methods of geostatistics and GIS, this paper studied the spatial variability of Cu, Zn, Ni, Cr As, Hg, Cd and Pb contents in the farmland topsoil (0～20 cm) of Qianan City, Hebei Province. The results showed that the average contents of test metals were under the secondary standard of environmental quality standard for soil (GB 156181995), and belonged to moderate variability. The theoretical models of semi-variance of Cu, Zn, Ni, Cr and As contents fitted exponential models, and their spatial correlations were strongly spatial dependence; while the theoretical models of Hg and Cd contents fitted spherical models, and their spatial correlations were moderately spatial dependence. The Pb content had pure nugget effect, and was weakly spatial dependence. In whole research scale, Pb content had lasting variability, while the other seven heavy metals contents had the spatial variability mainly caused by their spatial correlation parts. The ranges of heavy metals spatial correlations were about 11 km to 20 km. The Kriging’s interpolation of Cu, Zn, Ni, Cr, Hg, As and Cd contents showed that their contents were higher in northern mountainous area, but lower in mid basin.

Evaluation of heavy metals bioavailability and mobility in polluted soils: A comparison of four methods

ZHANG Mingkui; FANG Liping; ZHOU Cui

2006, 17(08):  1501-1504 . 

Asbtract ( 2801 )   PDF (310KB) ( 1157 )  

The accumulation of heavy metals in soil could give impact to the environment, and the impact is related to the accumulated heavy metals’ bioavailability and mobility. This paper studied the feasibility of four methods, i.e., total analysis, sequential fractionation, chemical extraction, and column leaching, in evaluating the bioavailability and mobility, and the results showed that because of the difference in chemical forms of the metals in different soils, the total concentration of the metals in soil was not suitable to evaluate their bioavailability and mobility. Exchangeable forms of the metals obtained by chemical fractionation could better reflect, while the organic matter-bound forms of some metals had definite correlation with the bioavailability and mobility. There were no significant correlations between the oxides-bound and residual metals and the bioavailability and mobility. Column leaching was also feasible to evaluate the bioavailability and mobility. 0.01 mol·L^-1 CaCl₂ and 1 mol·L^-1 NH₄OAc extractable metals were significantly correlated with the metals concentrations in surface runoff and plant, and could better predict the potential runoff of heavy metals from soil and the accumulation of the metals in plants.

Coercion and damage of Cu pollution on Artemisia lavandulaefolia灯growth

ZHEN Quan; YAN Mi; YANG Hongfei; LIU Dengyi; WANG Youbao

2006, 17(08):  1505-1510 . 

Asbtract ( 2227 )   PDF (834KB) ( 1040 )  

By the method of solution culture, this paper studied the coercion and damage of Cu pollution on the growth of Artemisia lavandulaefolia. The Cu concentration was set as 2.5, 5, 10, 20 and 40 mg·L^-1, experimental duration was 14 days, and the growth and physiological indices of plants were tested. The results showed that the growth of A. lavandulaefolia was stimulated at low Cu concentration (2.5 mg·L^-1), while inhibited at higher Cu concentrations (5～40 mg·L^-1). There was a significant negative correlation between each growth index and Cu concentration, and pigments contents had the similar trend. The sensibility of various photosynthetic pigments to Cu was in the order of chlorophyll a＞chlorophyll a+b＞chlorophyll b＞carotenoid. Cell membrane permeability, O₂^-· generation rate, and MDA content decreased slightly at 2.5 mg Cu ·L^-1, and then increased with increasing Cu concentration. The activities of POD, SOD and CAT increased first but decreased then with the increasing Cu concentration, and the endurance index of root showed the same trend, being ＞0.5 at the Cu concentration less than 20 mg·L^-1 while decreased to 0.36 at 40 mg Cu·L^-1.

Effects of sediments on submerged macrophytes growth

CHEN Kaining^1,2; CHEN Xiaofeng³; CHEN Weimin¹; Liu Ensheng²; LAN Cejie¹; XU Hai¹

2006, 17(08):  1511-1516 . 

Asbtract ( 2348 )   PDF (1085KB) ( 1184 )  

With mesocom experiment, this paper studied the effects of different sediments (sandstone, clay and mud) in Taihu Lake of China on the growth of four submerged macrophytes Vallisneria natans, Potamogeton malaianus, Hydrilla verticillata, and Ceratophyllum demersum. The results showed that among the test sediments, mud was more available. When growing on sandstone, clay and mud, the mean biomass of V. natans, P. malaianus, H. verticillata and C. demersum was 72.37, 126.25 and 134.10 g, 40.0, 72.10 and 90.70 g, 0.27, 6.58 and 73.64 g, and 0.17, 3.26 and 84.42 g, respectively. V. natans and P. malaianus had a stronger adaptability to the clay with lower nutrients contents, while H. verticillata and C. demersum didn’t. All the test species grown on sandstone had the lowest biomass and shoot height, and H. verticillat and C. demersum were not able to survive by the end of the experiment. V. natans had a lower root activity (TTC) than P. malaianus, being 0, 0.16±0.05 and 0.36±0.33 mg·g^-1·h^-1, and 2.68±0.34, 2.30±0.77 and 5.24±0.67 mg·g^-1·h^-1 when growing on sandstone, clay, and mud, respectively. The oxygen release from the root systems of test submerged macrophytes was in the order of V. natans＞P. malaianus＞H. verticillata. The measurements of chlorophyll content, cell membrane permeability, and MDA also had the similar trends mentioned above.

Effects of rearing density on juvenile Acipenser schrenckii digestibility, feeding rate and growth

SHI Xiaotao¹; LI Dapeng¹; ZHUANG Ping²; ZHANG Xuezhen¹; NIE Fen¹

2006, 17(08):  1517-1520 . 

Asbtract ( 2122 )   PDF (845KB) ( 1034 )  

A 60-day rearing experiment was conducted in this study. The initial weight of juvenile Acipenser schrenckii was 43.90 ± 1.75 g, and the initial rearing density was 0.525 (LSD), 1.171 (MSD), and 2.138 (HSD) kg·m^-2, respectively. The results showed that with increasing rearing density, the specific growth rate (SGR) and daily weight gain (DWG) of juvenile A. schrenckii were significantly decreased, while net yield (NY) was increased. The digestibility was significantly higher in LSD and MSD than in HSD, while that in LSD and MSD was nearly the same. The feeding rate in MSD was significantly lower than that in HSD, but slimly higher than that in LSD. There was a significant negative linear correlation between food conversion ratio (FCR) and digestibility, and a significant positive linear correlation between SGR and digestibility.

Adaptability of Moina affinis (Crustacea: Cladocera: Moinidae) to seawater salinity

ZHAO Wen; YU Boshi; WANG Ting; SONG Liang

2006, 17(08):  1521-1525 . 

Asbtract ( 2265 )   PDF (1148KB) ( 1119 )  

By the methods of experimental ecology, this paper studied the effects of different salinity (0, 1, 2, 3, 4, 5) on the survival, growth, and reproduction of Moina affinis (Crustacea: Cladocera: Moinidae) at 25 ℃±0.5 ℃ under laboratory conditions, aimed to know the adaptability of freshwater cladocerans to seawater salinity. The results indicated that when the salinity increased from 0 to 5, the mean lifespan of M. affinis was 16.8±1.3, 17.8±3.5, 14.2±5.7, 13.0±1.6, 9.6 ±1.5 and 6.6±1.8 days, intrinsic increase rate (r_m) was 0.91±0.01, 0.96±0.01, 0.86±0.10, 0.86±0.05, 0.49±0.18 and 0.24±0.06 d^-1, mean eggs production per clutch was 34.5±3.7, 34.2±3.9, 27.5±7.1, 34.6±3.9, 12.3±5.0 and 9.1±2.1 ind., and life fecundity was 410±32, 445±84, 250±106, 294 ±47, 59±38 and 24±6 ind., respectively. There was a significant difference in mean lifespan, intrinsic increase rate, and mean eggs production per clutch between treatments salinity 0, 1, 2 and 3 and treatments salinity 4 and 5, and in life fecundity between treatments salinity 0 and 1 and treatments salinity 2, 3, 4 and 5. The body length and daily growth rate was lower in control than in other treatments. It was suggested that salinity 5 was the maximum threshold salinity for the survival and reproduction of M. affinis, but after a short period of acclimatization in diluted seawater, the maximum threshold could reach 6.5.

Barnacle damage and its control in young mangrove plantations: A research review

XIANG Ping¹; YANG Zhiwei^{1, 2}; LIN Peng^{1, 2}

2006, 17(08):  1526-1529 . 

Asbtract ( 2297 )   PDF (384KB) ( 1148 )  

With the increasing area of restored mangrove vegetation, marinefouling organisms, barnacle in particular, are suggested to be an important factor affecting the survival and growth of mangrove seedlings. This paper reviewed the biochemical and ecological studies on the settlement of barnacle, its damage on mangrove seedlings, and its chemical control. The settlement and distribution model of barnacle on mangroves is significantly affected by the environmental factors such as seawater salinity, tide inundating depth, canopy density, hydrographical regime, and some biotic factors, but few are known about the amino acid composition and onedimension structure of barnacle’s adhesive proteins, especially their processes and mechanisms of cross-link, aggregation, and adhesion. More attention should be paid on understanding the damage mechanisms and its weight of barnacle on mangrove seedlings, and the study on the response and adaptation models of individual plant in nature mangrove ecosystem to barnacle disturbance should be strengthened, which are potentially valuable for the research of barnacle control.

Remediation of polycyclic aromatic hydrocarbons in non-fluid medium with immobilized microorganism technique

SU Dan^1,2; LI Peijun¹; JU Jingli¹; XU Huaxia¹

2006, 17(08):  1530-1534 . 

Asbtract ( 2191 )   PDF (394KB) ( 1008 )  

The remediation of polycyclic aromatic hydrocarbons (PAHs) in non-fluid medium is a difficult and urgent task for environmental scientists. Due to the particularities of nonfluid medium, conventional techniques cannot work effectively, while bioremediation techniques using free microorganism also have many limitations that restricted the use of microorganism in removing PAHs from non-fluid medium. Immobilized microorganism (IM) technique is a proven approach in increasing the stability of microorganism under unfavorable conditions, which can not only provide a special microenvironment to protect dominant microorganisms from the malignant competition of aboriginal microorganism, but also improve the tolerance against toxic compounds in environment. Biodegradation using immobilized cells has been widely investigated for numerous toxic compounds in fluid medium such as in wastewater, or in half-fluid medium such as in slurry. In this paper, based on analyzing the characteristics of IM technique and its feasibility, the problem and development of future research were presented, and the new technique using IM to remediate PAHs in non-fluid medium was put forward.

Soil carbohydrates: their determination methods and indication functions

ZHANG Wei^1,2; XIE Hongtu¹; HE Hongbo¹; ZHENG Lichen^1,2; Wang Ge³

2006, 17(08):  1535-1538 . 

Asbtract ( 2375 )   PDF (352KB) ( 1186 )  

Soil carbohydrates are the important component of soil organic matter, and play an important role in soil aggregation formation. Their hydrolysis methods involve sulfur acid (H₂SO₄), hydrochloric acid (HCl), and trifluoroacetic acid (TFA) hydrolysis, and their determination methods include colorimetry, gasliquid chromatography (GLC), high performance liquid chromatography (HPLC), and high performance anionexchange chromatography with pulsed amperometric detection (HPAE-PAD). This paper summarized the methods of carbohydrates’ hydrolysis, purification and detection, with focus on the derived methods of GLC, and briefly introduced the indication functions of carbohydrates in soil organic matter turnover.

Research advances in monitoring and detecting insect pesticide-resistance

PAN Zhiping^1,2; LI Dunsong¹

2006, 17(08):  1539-1543 . 

Asbtract ( 2077 )   PDF (369KB) ( 1038 )  

This paper reviewed the research advances in the techniques of monitoring and detecting insect pesticide-resistance, including biological, electrophysiological, biochemical, immunological, and molecular biological, and indicated the problems existing in the application of these techniques. With the development of related theories and experimental techniques, more rapid detection techniques were provided for early monitoring insect pesticide-resistance, which made the related study have more new progress.

Resistant physiology of three mangrove species in a constructed wetland sewage treatment system

JING Yuanxiao^1,2; REN Yanli²; YANG Danjing³; HAN Huili²; XIAO Lin²; CHEN Guizhu¹

2006, 17(08):  1544-1546 . 

Asbtract ( 2403 )   PDF (820KB) ( 1185 )  

This paper studied the resistant physiology of three mangrove species, Sonneratia caseolaris, Aegiceras corniculatum and Bruguiera gymnorrhiza in a subsurface flowconstructed wetland sewage treatment system under freshwater condition. The results showed that in a year period, the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities of three mangrove species increased gradually and maintained at a high level, the proline content reached the maximum from July to September, while the plasma membrane permeability did not show any obvious change. In comparing with those grown in the Futian Nature Reserve of Shenzhen, three mangrove species in the test sewage treatment system had lower SOD, POD and CAT activities and higher proline content, while no significant difference was observed in the malondialdehyde (MDA) content and plasma membrane permeability. It was suggested that three mangrove species could adapt to the subsurface flow-constructed wetland sewage treatment system under freshwater condition.

Three-dimensional spatial distribution patterns of Monochamus alternatus and its natural enemy Dastarcus helophoroides

CHEN Xiangyang^1，2; ZOU Yunding¹; DING Yuzhou¹; WU Houzhang¹; LI Zhengzhi¹; LIN Xuefei¹; WANG Wenjun¹; TIAN Fangxin¹

2006, 17(08):  1547-1550 . 

Asbtract ( 2213 )   PDF (338KB) ( 1029 )  

In 2003～2005, the Monochamus alternatus infected Pinus thunbergii, P. massoniana and P. elliotii in pure and mixed forests were selected as attractants and dissected with one meter section manner, and five aggregation indices were used to analyze the spatial distribution patterns of M. alternatus and its natural enemy Dastarcus helophoroides. The results showed that M. alternatus and D. helophoroides had the horizontal distribution indices of diffused coefficient C＞1, diffused index I_δ＞1, Kuno index C_A＞0, clump intensity index I＞1, and swarm index I_w＞1 in the two stands, suggesting their aggregated horizontal distribution patterns, and except D. helophoroides on the P. massoniana in mixed forest appeared assemble vertical distribution, these two insects all had an even vertical distribution, with their C＜1, I_δ＜1, C_A＜0, I_w＜1, and I＜0. The spatial distribution patterns of M. alternatus and D. helophoroides were consistent, and the latter was spatially following the former.

Soil-landscape relationships in Shenyang area

HU Hongxiang^1,2; WANG Jingkuan²; YU Zhongxiang¹; WANG Qiubing²

2006, 17(08):  1551-1555 . 

Asbtract ( 2265 )   PDF (341KB) ( 1125 )  

Soil is a natural object distributed in succession on the earth surface, and its genesis and development has a close connection with landscape. Based on the field survey and the comparative analysis of soil profile characteristics, particle composition, and some chemical characteristics in Shenyang area, the soils in this area were classified into three orders (luvisols, cambisols and entisols), five suborders, seven groups, nine subgroups, nine families, and fourteen series, according to the “Chinese Soil Taxonomy (revised three drafts)”. There existed a good corresponding relationship between soil types and their landscape characteristics. Soil property was not only a synthetic reflection of landscape elements topography, parent material, water condition and so on, but also an integral result of longterm environmental changes and anthropogenic influences.