Table of Content

18 December 2013, Volume 24 Issue 12

Previous Issue    Next Issue

Soil organic carbon density and its influencing factors of major forest types in the forest region of Northeast China.

WEI Ya-wei1,2,4, YU Da-pao1, WANG Qing-jun3, ZHOU Li1, ZHOU Wang-ming1, FANG Xiang-min1,4, GU Xiao-ping1,2,4, DAI Li-min1

2013, 24(12):  3333-3340. 

Asbtract ( 2355 )   PDF (936KB) ( 700 )  

The five main forest types, i.e. larch forest, birch forest, coniferous mixed forest, broadleaved mixed forest, and coniferous and broadleaved mixed forest, with varied age classes (young, midaged, premature, and over mature) were selected to investigate the variation of soil organic carbon density in the forest region of Northeast China. Results showed that both soil organic carbon content and density were relatively larger in the top soil layer across the five forest types, decreased gradually with soil depth, and varied insignificantly with either forest type or forest age class. The forest soil carbon density was concentrated in the top 20 cm of soil which accounted for 84.7%-86.1%, 51.7%-59.8% and 51.2%-53.4% of total soil carbon density in the Daxing’an, Xiaoxing’an and Changbai mountains, respectively. The total soil organic carbon density decreased significantly with increasing latitude, which might be attributed mainly to the thickness of soil layers in forest region of Northeast China.

 

Effects of understory removal on soil labile organic carbon pool in a Cinnamomum camphora plantation.

WU Ya-cong, LI Zheng-cai, CHENG Cai-fang, LIU Rong-jie, WANG Bin, GERI Le-tu

2013, 24(12):  3341-3346. 

Asbtract ( 1174 )   PDF (516KB) ( 560 )  

Taking a 48-year-old Cinnamomum camphora plantation in the eastern area of our subtropics as test object, this paper studied the labile organic carbon contents and their ratios to the total organic carbon (TOC) in 0-60 cm soil layer under effects of understory removal (UR). As compared with no understory removal (CK), the soil TOC and easilyoxidized carbon (EOC) contents under UR decreased, with a decrement of 4.8%-34.1% and 27.1%-36.2%, respectively, and the TOC and EOC contents had a significant difference in 0-10 cm and 0-20 cm layers, respectively. The watersoluble organic carbon (WSOC) (except in 0-10 cm and 10-20 cm layers) and light fraction organic matter (LFOM) under UR increaesd, but the difference was not significant. The ratio of soil WSOC to soil TOC in UR stand was higher than that in CK stand, while the ratio of soil EOC to soil TOC showed an opposite trend. In the two stands, soil WSOC, EOC, and LFOM had significant or extremely significant correlations with soil TOC, and the correlation coefficients of soil EOC and LFOM with soil TOC were higher in UR stand than in CK, but the correlation coefficient between soil WSOC and TOC was in opposite. The soil EOC, LFOM, and TOC in the two stands were significantly or extremely significantly correlated with soil nutrients, but the soil WSOC in UR stand had no significant correlations with soil hydrolyzable N, available P, exchangeable Ca, and exchangeable Mg.

Seasonal dynamics of soil labile nitrogen pools and net nitrogen mineralization in subalpine forests along an elevational gradient in western Sichuan, China.

YIN Rui, XU Zhen-feng, WU Fu-zhong, YANG Wan-qin, XIONG Li, XIAO Sa, MA Zhi-liang, LI Zhi-ping

2013, 24(12):  3347-3353. 

Asbtract ( 2092 )   PDF (797KB) ( 535 )  

The seasonal dynamics of soil labile nitrogen pools and net nitrogen mineralization of three subalpine forests along an elevation gradient (3600, 3300 and 3000 m), western Sichuan, China were examined. Obvious seasonal dynamics were found in soil labile nitrogen pools (ammonium, nitrate, microbial biomass nitrogen and dissolved organic nitrogen) and net nitrogen mineralization rate, but the seasonality varied with the measured nitrogen pools. The concentrations of soil nitrate (8.38-89.60 mg·kg^-1) were significantly higher than those of ammonium (0.44-8.43 mg·kg^-1) in four sampling periods (non-growing season, early, middle and late growing season). Regardless of the elevation, the rate of soil net nitrogen mineralization was negative (-0.77 to -0.56 mg·kg^-1·d^-1) early in the growing season, but positive in the other three periods. Except for nitrate, the contents of ammonium, microbial biomass nitrogen and dissolved organic nitrogen varied significantly with elevation and the altitude effects on those pools were dependent on seasons. In summary, soil nitrification was the major process of net soil nitrogen mineralization and soil nitrogen mineralization was not affected by elevational gradient. Soil nitrogen mineralization (0.42-0.99 mg·kg^-1·d^-1) in winter was considerable in this area. Relatively high inorganic nitrogen in early spring might be favorable for vegetation growth, but might also be lost from soil ecosystem through leaching.

Contributions of soil fauna to litter decomposition in alpine/subalpine forests.

LIU Rui-long1, LI Wei-min2, YANG Wan-qin1, TAN Bo1, WANG Wen-jun1, XU Zhen-feng1, WU Fu-zhong1

2013, 24(12):  3354-3360. 

Asbtract ( 1934 )   PDF (578KB) ( 471 )  

A field experiment was conducted using the litterbag method to quantify the contribution of soil fauna to litter mass loss of Salix paraplesia, Sabina saltuaria, Betula albosinensis and Abies faxoniana during different key periods of the decomposition process of the first year (from November 2011 to October 2012). The results showed that the mass loss rate showed S. paraplesia > B. albosinensis > A. faxoniana > S. saltuaria, and the rate in the growing season was greater than in the freezethaw season. The contribution rate of soil fauna to the mass decomposition displayed as S. saltuaria (26.7%)>A. faxoniana (18.8%) > B. albosinensis (15.7%) > S. paraplesia (13.2%), which was higher in the freezethaw season than in the growing season for litter of B. albosinensis and A. faxoniana while vice versa for litter of B. albosinensis and A. faxoniana. The contribution of soil fauna was mainly related to organic C, P and N/P in the freeze-thaw season, while N,  C/N,  lignin and lignin/cellulose in the growing season.

Litter decomposition of typical forests along an altitude gradient in Mt. Shennongjia, Hubei, China.

PAN Dong-rong1,2, LIU Xiao-ni1, SHEN Guo-zhen2, XIE Zong-qiang2, LUO Lu2, LIU Lei3

2013, 24(12):  3361-3366. 

Asbtract ( 1624 )   PDF (461KB) ( 594 )  

Based on the litterbag method, we explored the decomposition dynamics of the litter from the evergreen broad-leaved forests, the mixed evergreen and deciduous broadleaved forests, and the deciduous broad-leaved forests along an altitude gradient in Mt. Shennongjia, Hubei, China. According to the decomposition rate, the decomposition of the litter could be divided into early stage (0-360 days) and later stage (361-720 days). With the increase of altitude, the mass loss rates of the litter from the three types of forests at the early stage were 2.62-4.08 times that of the later stage, the litter decomposition rates at the early stage were 2.71, 1.72 and 2.69 times of that at the later stage, respectively, and  95% decomposition of the litter needed 3.84, 4.54 and 4.16 years respectively. The decomposition rate at the later stage was significantly correlated with C/N, and the contents of N, hemicelluloses, cellulose and lignin.

Effects of sand burial on growth and physiological process of Agriophyllum squarrosum seedlings in Horqin Sand Land of Inner Mongolia, North China.

ZHAO Ha-lin1, QU Hao1, ZHOU Rui-lian2, WANG Jin2, LI Jin1, YUN Jian-ying1

2013, 24(12):  3367-3372. 

Asbtract ( 1383 )   PDF (702KB) ( 449 )  

In 2010-2011, a sand burial experiment was conducted on the Horqin Sand Land of Inner Mongolia to study the  growth characteristics and physiological properties of Agriophyllum squarrosum seedlings  under different depths of sand burial. The A. squarrosum seedlings had stronger tolerance against sand burial. The seedling growth could be severely inhibited when the burial depth exceeded seedling height, but some seedlings could still be survived when the burial depth exceeded 1.66 times of seedling height. When the burial depth did not exceed the seedling height, the seedling MDA content and membrane permeability had no significant change, but the lipid peroxidation was aggravated and the cell membrane was damaged with increasing burial depth. Under sand burial stress, the seedling SOD and POD activities and proline content increased significantly, while the seedling CAT activity and soluble sugar content deceased. Sand burial decreased the leaf photosynthetic area and damaged cell membrane, inducing the increase of seedling mortality and the inhibition of seedling growth. The increase of SOD and POD activities and proline content played a definite role in reducing the sand burial damage to  A. squarrosum seedlings.

Water impounding characteristics of bamboo-shaped rainwater harvesting ditch in the hilly loess region.

LIN Jun1, WANG You-ke2,3, WEI Xin-dong3,4, XIAO Sen1, ZHANG Xue3

2013, 24(12):  3373-3380. 

Asbtract ( 1635 )   PDF (851KB) ( 438 )  

Bamboo-shaped rainwater harvesting  ditch (BRHD) is a new water harvesting and application technology being promoted in the hilly loess region of North Shannxi Province. This paper measured the soil moisture condition and water storage capacity of BRHDs filled with straw, branch or gravel through field and simulated rainfall experiments to evaluate the water holding and absorption capacity of different BRHD fillers. From May to October, the water storage of BRHDs showed a decrease trend at first and then increased in field experiment. The water storage depths within 30-200 cm profile of branch ditch (BD), gravel ditch (GD) and straw ditch (SD) were 186.76, 177.23 and 169.26 mm in May, respectively, and increased by 14.24, 20.28 and 21.23 mm in October, respectively. In contrast, the water storage depth of the level bench was reduced by 6.52 mm in October from 185.76 mm in May. The soil water restoration depth was different between BRHDs with different fillers and the level bench within 30-200 cm profile in October. The SD and BD had the deepest restoration depth (140 cm), followed by GD (110 cm), and the level bench was the minimum (80 cm). Through rainfall simulation experiment, the amount of water intercepted by BRHD was in the order of SD (99.5 L)>GD (91 L)>BD (71.5 L). The waterholding rate of straw and branch showed logarithmic function with soaking time, while the waterabsorption rate followed a power function. Moreover, there was a negative logarithm correlation between waterholding rate and waterabsorption rate. Straw showed a better water holding and absorption capacity than branch. Gravel had a weak water holding and absorption capacity which was almost not changed during soaking, while it displayed a negative liner correlation between water holding rate and absorption rate. The three kinds of BRHDs could be applied in the hilly loess region, and that filled with straw would exhibit the best capacity of water interception and holding.

Fire behavior of Quercus mongolica  leaf litter fuelbed under zero-slope and no-wind conditions. Ⅲ. Analysis and modelling of fireline intensity, fuel consumption, and combustion efficiency.

ZHANG Ji-li, LIU Bo-fei, DI Xue-ying, CHU Teng-fei, JIN Sen

2013, 24(12):  3381-3390. 

Asbtract ( 1205 )   PDF (1071KB) ( 369 )  

Mongolian oak (Quercus mongolica) is an important constructive and accompanying species in mixed broadleaf-conifer forest in Northeast China. In this paper, a laboratory burning experiment was conducted under zero-slope and no-wind conditions to study the effects of fuel moisture content, loading, and thickness on the fireline intensity, fuel consumption, and combustion efficiency of the Mongolian oak leaf litter fuelbed. The fuel moisture content, loading, and thickness all had significant effects on the three fire behavior indices, and there existed interactions between these three affecting factors. Among the known models, the Byram model could be suitable for the prediction of local leaf litter fire intensity only after re-parameterization. The re-estimated α and β parameters of the re-parameterized Byram model were 98.009 and 1.099, with an adjusted determination coefficient of 0.745, the rooted mean square error (RMSE) of 8.676 kW·m^-1, and the mean relative error (MRE) of 21%, respectively (R²=0.745). The reestimated a and b by the burning efficiency method proposed by Albini were 0.069 and 0.169, and the reestimated values were all higher than 93%, being mostly overestimated. The Consume model had a stronger suitability for the fuel. The R² of the general linear models established for fireline intensity, fuel consumption, and burning efficiency was 0.82, 0.73 and 0.53, and the RMSE was 8.266 kW·m^-1, 0.081 kg·m^-2, and 0.203, respectively. In low intensity surface fires, the fine fuels could not be completely consumed, and thus, to consider the leaf litter and fine fuel in some forest ecosystems being completely consumed would overestimate the carbon release from forest fires.

Linear mixed modeling of branch biomass for Korean pine plantation.

DONG Li-hu, LI Feng-ri, JIA Wei-wei

2013, 24(12):  3391-3398. 

Asbtract ( 1324 )   PDF (867KB) ( 539 )  

Based on the measurement of 3643 branch biomass samples of 60 Korean pine (Pinus koraiensis) trees from Mengjiagang Forest Farm, Heilongjiang Province, all subset regressions techniques were used to develop the branch biomass model (branch, foliage, and total biomass mo-dels). The optimal base model of branch biomass was developed as lnw=k₁+k₂lnL_b+k₃lnD_b. Then, linear mixed models were developed based on PROC MIXED of SAS 9.3 software, and evaluated with AIC, BIC, Log Likelihood and Likelihood ratio tests. The results showed that the foliage and total biomass models with parameters k₁, k₂ and k₃ as mixed effects showed the best performance. The branch biomass model with parameters k₁ and k₂ as mixed effects showed the best performance. Finally, we evaluated the optimal base model and the mixed model of branch biomass. Model validation confirmed that the mixed model was better than the optimal base model. The mixed model with random parameters could not only provide more accurate and precise prediction, but also showed the individual difference based on variancecovariance structure.

Soil N/P ratio distribution characteristics of alpine grassland ecosystem in QinghaiTibet Plateau. 

WANG Jian-lin1, ZHONG Zhi-ming2, WANG Zhong-hong1, CHEN Bao-xiong2, ZHANG Xian-zhou2, SHEN Zhen-xi2, HU Xing-xiang1, Dacizhuoga1

2013, 24(12):  3399-3406. 

Asbtract ( 1761 )   PDF (1028KB) ( 518 )  

The distribution characteristics of soil N/P ratio in alpine grassland ecosystem of Qinghai-Tibet Plateau were surveyed by field investigation and laboratory analysis. Horizontally, soil N/P ratio was generally higher in west and lower in east in a manner of staggered patch distribution, with higher N/P ratios mainly centralized in the hinterland of northern part of Tibet Plateau and in the lake basin area of the northern foot of Himalayas. Significant differences in soil N/P ratio were observed among grassland types and natural transects. Vertically, the distribution of N/P ratio along the soil profile from aboveground to underground among different grass types could be categorized into five patterns, including low-high-low-high, low-high-low, low-high, high-low-high-low, and high-low-high. The N/P ratio showed a significant positive correlation with soil bulk density at 0-20 cm depth, soil water content at 20-30 cm depth, contents of soil available K and total nitrogen, respectively. However, it showed significant negative correlation with soil bulk density at 20-30 cm depth, contents of soil available P and total P, respectively.

Variation of soil physicochemical and microbial properties in degraded steppes in Hulunbeir of China.

LIN Lu1,2, WU Yun-na2, KENJI Tamura3, HUO Guang-wei1,2, LUO Wen-tao4,5, LU Jian-zhou1

2013, 24(12):  3407-3414. 

Asbtract ( 1484 )   PDF (996KB) ( 412 )  

To investigate the influence of degradation on grassland, we sampled soil and plants at three sites respectively under light, moderate and severe degradation in Hulunbeir Grassland in northern China and analyzed the differences and relationships among soil physicochemical characters, enzyme activity, soil microorganism quantity and aboveground biomass. The results showed that species richness of the moderately degraded site was highest while the aboveground biomass at the lightly degraded site was significantly higher than at the severely degraded site. Soil moisture content, nutrients (organic matter and total nitrogen) concentrations, soil microorganism quantity and enzyme activity were all decreased significantly in the degraded sites, whereas both the soil hardness and bulk density showed an opposite trend. The soil microbial biomass carbon and nitrogen contents ranged from 128 to 185 g·kg^-1 and from 5.6 to 13.6 g·kg^-1, respectively. The soil dehydrogenase and urease activities negatively correlated with soil bulk density but positively correlated with total nitrogen, organic matter, microbial biomass carbon and nitrogen. The aboveground biomass showed significantly positive correlation with the number of soil bacteria and fungi.

Multi-scale correlation analysis of soil organic carbon with its influence factors using wavelet transform.

JIANG Chun1,2,3,4, QIAN Le-xiang1, WU Zhi-feng1, WEN Ya5, DENG Nan-rong3

2013, 24(12):  3415-3422. 

Asbtract ( 2309 )   PDF (804KB) ( 465 )  

Based on GIS, this paper chose the soil organic carbon (SOC) density in soil surface layer (0-20 cm) and its influence factors (NDVI, elevation, slope and aspect) as research objects, one-dimensional discrete wavelet transform (DWT) was used as the multiscale decomposition tool to quantitatively revealed the multiscale correlation relationships among SOC density and its influence factors on the grid scale along 4 transects of the mountainous area of Guangdong Pro-vince. The results showed that the correlation among SOC density and its influence factors was scale-dependent with varying degree. The influence of NDVI was strongest  at the scales of 2, 8 and 16 km, while elevation showed its greatest influence at the scales of 8 and 16 km. The control action of slope was rather weak, with a less significant correlation depending on scale. The negative effect of aspect became stronger with increasing scale at  >2 km scale. The SOC density of the different transects was affected by various factors, of which NDVI and elevation were the main factors, and slope and aspect only reacted with individual transects at larger scales.

Biological properties of lateritic red soil and their relationships with soil fertility in Southern China under different land use types.

ZHANG Jing, GAO Yun-hua, ZHANG Chi, ZHOU Bo, LI Jing-juan, YANG Xiao-xue, XU Huan, DAI Jun

2013, 24(12):  3423-3430. 

Asbtract ( 2122 )   PDF (517KB) ( 410 )  

Taking the lateritic red soil on a typical slopeland in Southern China as test object, this paper studied the soil microbial properties, enzyme activities, and their relationships with soil fertility under- four land use types (newly cultivated dryland, shrub land, Eucalyptus land, and orchard). There existed significant differences in the soil biological properties under different land use types, among which, orchard soil had the highest microbial quantity and enzyme activities, newly cultivated dryland soil had the fastest soil respiration rate, the fewest soil microorganism quantity, and the lowest enzyme activities, whereas shrub land and woodland soils had the biological properties ranged between newly cultivated dryland and orchard soils, and there was a high similarity in the biological properties between shrub land and woodland soils. Under different land use types, the soil microbial quantity and enzyme activities were positively correlated with soil organic carbon and most of the soil nutrients. It was suggested the soils with high soil organic matter content and high fertility level were beneficial to the soil microbial growth and enzyme activities.

Relationship between tumorous stem mustard yield and soil fertility in Fuling, Southwest China.

ZHAO Huan1,2, QIN Song2, WANG Zheng-yin1, LI Hui-he3, LU Hui-feng1

2013, 24(12):  3431-3138. 

Asbtract ( 1284 )   PDF (469KB) ( 373 )  

By combining field investigation and indoor chemical analysis, the relationship between tumorous stem mustard yield and soil fertility factors was investigated in the main planting areas of tumorous stem mustard in Fuling, Southwest China. The results showed that available Ca, Mg, Fe, Mn, Cu and Zn in the soil were rich (3034, 260, 11.2, 26.1, 1.15 and 1.50 mg·kg^-1, respectively), available P was moderate (19.3 mg·kg^-1), and organic matter, available N, available K and available S were deficient (9.05 g·kg^-1, 89.2 mg·kg^-1, 106 mg·kg^-1 and 27.0 mg·kg^-1, respectively). The yield of tumorous stem mustard was significantly positively correlated with soil pH and available Ca, whilst significantly (P<0.01) negatively correlated with available Fe. The influence order of soil fertility factors on the yield of tumorous stem mustard was available Mn > available Cu > pH > available Fe > available K > available Ca > available Mg > available S > available N > available Zn > organic matter > available P. The linear equation (Y=31636+3.63X₆) of soil available Ca and the yield, was established by stepwise regression analysis.

Spatiotemporal characteristics of urban land expansion in central area of Shanghai, China.

HU Han-wen1, WEI Ben-sheng1, SHEN Xing-hua1, LI Jun-xiang1,2

2013, 24(12):  3439-3445. 

Asbtract ( 2041 )   PDF (1648KB) ( 500 )  

Using the high spatial resolution (2.5 m) color-infrared aerial photos acquired in 1989, 1994, 2000 and 2005, this paper analyzed the spatiotemporal characteristics of rapid urban expansion in central Shanghai with urban expansion intensity index and gradient analysis. Results showed that urban land use in Shanghai increased rapidly in a “pancake” style during the study period, and the anisotropic urban expansion moved the urban center 2.62 km toward southwest. The urban land use expansion intensity doubled and showed a rural-urban gradient. The most intensive urban expansion zone fell in the rural-urban transition zone, indicating the dominance of peripheral expansion as the primary urban expansion mode in Shanghai. However, the urban land use intensity decreased with time at the urban center. The primary driving forces of urban expansion included support from government policies and decisionmaking, enhanced economic activities, societal fixed assets investment, urban infrastructure investment, extension of transportation routes, as well as increase in urban population.

 

Urban heat island  effect based on urban heat island source and sink indices in Shenyang, Northeast China.

LI Li-guang1, XU Shen-lai2, WANG Hong-bo1, ZHAO Zi-qi1, CAI Fu1, WU Jin-wen1, CHEN Peng-shi3, ZHANG Yu-shu1

2013, 24(12):  3446-3452. 

Asbtract ( 1554 )   PDF (1764KB) ( 440 )  

Based on the remote images in 2001 and 2010, the source and sink areas of urban heat island (UHI) in Shenyang City, Northeast China were determined by GIS technique. The effect of urban regional landscape pattern on UHI effect was assessed with land surface temperature (LST ), area rate index (CI) of the source and sink areas and intensity index (LI) of heat island. The results indicated that the land use type changed significantly from 2001 to 2010, which significantly changed the source and sink areas of UHI, especially in the second and third circle regions. The source and sink areas were 94.3% and 5.7% in the first circle region, 64.0% and 36.0% in the third circle region in 2001, while they were 93.4% and 6.6%, 70.2% and 29.8% in 2010, respectively. It suggested that the land use pattern extended by a round shape in Shenyang led to the corresponding UHI pattern. The LST in the study area tended to decrease from the first circle region to the third. The UHI intensity was characterized with a single center in 2001 and with several centers in 2010, and the grade of UHI intensity was in a decreasing trend from 2001 to 2010. The absolute value of CI increased from the first circle region to the third, and the LI was close to 1, suggesting the change in land use pattern had no significant influence on UHI in Shenyang.

Effects of fertilization on cotton growth and nitrogen use efficiency under salinity stress.

DAI Jian-long1,2, LU He-quan1, LI Zhen-huai1, DUAN Liu-sheng2, DONG He-zhong1

2013, 24(12):  3453-3458. 

Asbtract ( 1447 )   PDF (493KB) ( 550 )  

Cotton (Gossypium hirsutum) was raised at different salinity levels (0, 0.15% and 0.30%) by irrigating with fresh or seawater. The effects of fertilization (N, NK, NP and NPK) on plant growth, nitrogen (N) uptake and N use efficiency were studied. The results showed that salinity and fertilization both affected the biomass, agronomic N use efficiency, N bioavailability and nitrogen accumulation of plants, and significant interaction was observed between the two factors. Fertilization could improve  N use efficiency and nitrogen accumulation of plants under salinity stress, and significantly promoted the cotton yield. Among the fertilization treatments, N combined with P and K had the best effect. The benefit of fertilization was better under low salinity (0.15%) than under moderate salinity (0.3%).

Effects of water and light interaction on reactive oxygen metabolism in ginger leaves.

ZHANG Yong-zheng, LI Hai-dong, LI Xiu, XIAO Jing, XU Kun

2013, 24(12):  3459-3464. 

Asbtract ( 1479 )   PDF (792KB) ( 356 )  

To explore the relationship between water supply in roots, light intensity on leaves and reactive oxygen metabolism, the effects of various treatments including natural light plus normal watering (T₁), 50% shading plus normal watering (T₂), natural light plus PEG-6000 simulated drought (T₃), 50% shading plus simulated drought (T₄) on reactive oxygen level and antioxidant enzyme activity in ginger leaves were studied. The results showed that, 6 days after treatment, the O^-·₂ production rate and H₂O₂ and MDA contents remarkably increased in ginger leaves at midday. Treatment T₃ showed the greatest increment, followed by T₄, T₁ and T₂ in order. In addition, the activities of SOD and POD in all treatments and CAT in T₃ and T₄ noticeably decreased, while CAT in T₁ and T₂ exhibited a high activity at midday. Throughout the whole treatment, reactive oxygen level and antioxidant enzyme activities of ginger leaves in T₁ and T₂ remained stable, with a higher activity in T₁ than in T₂. However, the reactive oxygen level kept increasing in leaves exposed to treatments T₃ and T₄. Meanwhile, the activities of antioxidant enzymes increased firstly and then decreased. Taken together, this study demonstrated that drought stress, especially drought plus light stress, led to an increased accumulation of reactive oxygen in ginger leaves, while shading was conducive to maintaining high activity of protective enzymes, and therefore to reducing reactive oxygen level and alleviate drought-induced injury.

Effects of tillage in fallow period on soil water and nitrogen absorption and translocation by wheat plant.

REN Ai-xia, SUN Min, ZHAO Wei-feng, DENG Lian-feng, DENG Yan, GAO Zhi-qiang

2013, 24(12):  3471-3478. 

Asbtract ( 1329 )   PDF (436KB) ( 386 )  

Field test was carried out to study the effect of tillage in fallow period on soil water before sowing and growth stages, and nitrogen (N) absorption, translocation by wheat plant. The current data showed that tillage in fallow period improved the soil water at the depth of 0-300 cm before sowing and growth stages, especially in dry years. Such tillage significantly improved N accumulation in leaf, stem and sheath (SS) at anthesis, grain N accumulation at maturity, N mobilization in SS and the contribution of mobilized N to grain N, amount of mobilized N in leaf, level of N accumulation  before anthesis, N transportation from vegetative organs to grains after anthesis, and nitrogen accumulation after anthesis, which in turn enhanced the efficiency of N uptake. Deep tillage at 45 days after harvest had the best effect. Significant correlations were detected between soil water and N accumulation before anthesis as well as N translation from vegetative organs to grains after anthesis, particularly in dry years, while the correlation between soil water from sowing to anthesis and nitrogen accumulation amount after anthesis was significant in wet years, but not in dry years. Tillage in fallow period especially deep tillage after raining could benefit soil water preservation, as well as N absorption and translocation by plant.

Effects of shade-humid environment on the growth characteristics of different maize (Zea mays) hybrids.

YAN Qing-jiu, HUO Shi-ping, ZHANG Fang-kui, ZHANG Xing-duan, ZHANG Jian, XIANG Zhen-fan, YU Zhi-jiang, FENG Yun-chao

2013, 24(12):  3479-3486. 

Asbtract ( 1174 )   PDF (480KB) ( 349 )  

The growth traits of 18 maize hybrids were studied in natural and artificial simulation shade-humid environments. Significant differences were observed between the natural and shadehumid environments, and the air relative humidity in the shadehumid environment increased 15.0%-16.4%, the soil moisture increased 27.0%-78.4%, the illumination intensity decreased 72.9%-77.9%, and the quantum decreased 72.8%-79.6%. Shade did not affect the ambient temperature. The 7th leaf width, effective functional leaves, plant total leaves, tassel branch number, stem diameter, plant height, ear height, ear length, ear diameter, rows per ear, kernels per row, 100grain mass and grain yield per plant under the shadehumid environment showed negative variations (reduction in phenotypic values), with the grain yield per plant and plant height being reduced by 72.3% and 7.1% respectively, and the declining changes of the remaining traits ranging from 148%-53.8%. However, the 7th leaf length, 7th leaf lengthwidth ratio, anthesis to silking (ASI) duration, southern leaf blight (SLB) index and sheath blight index showed positive variations (increase in phenotypic values), with increases by 39.8%, 80.5%, 114.3%, 73.0% and 54.8%, respectively. The comprehensive shadehumidtolerant coefficient calculated from the seven traits of ASI, tassel branches, plant total leaves, plant height, individual grain yield, southern leaf blight and sheath blight index could be easily and reliably used to evaluate the shadehumidtolerant ability of the maize hybrids. According to this coefficient, the 18 hybrids could be classified into three categories, stronglyresistant, moderatelyresistant and weaklyresistant to the shade-humid environment.

Indices selection and comprehensive evaluation of salinity tolerance for peanut varieties.

ZHANG Zhi-meng, CI Dun-wei, DING Hong, SONG Wen-wu, FU Fang-ping, KANG Tao, DAI Liang-xiang

2013, 24(12):  3487-3494. 

Asbtract ( 1737 )   PDF (1141KB) ( 384 )  

A total of two hundred peanut varieties (lines) were exposed to different salt concentrations under pot cultivation, to evaluate salinity tolerance by indices such as emergence, morphology and biomass accumulation from emergence to seedling stage. The results showed that, as the salinity concentration increased, the emergence time was prolonged, plant morphology establishment was inhibited seriously, and biomass accumulation was reduced. The optimal concentration for evaluating salinity tolerance was 0.30%-0.45%. Ten indices were contributed to the mean membership function value by the membership function analysis. According to the correlation coefficient between indices and the mean membership function value, plant fresh mass, shoot fresh mass, root fresh mass, root dry mass, plant height and stem height could be the first selected indices for evaluating salinity tolerance of peanut plant. Plant dry mass, shoot dry mass, taproot length and emergence speed could be the second selected indices to comprehensively evaluate salinity tolerance of peanut plant. The 200 varieties were divided into 4 groups at different salinity concentrations, i.e. high salinity tolerance, salinity tolerance, salinity sensitivity, and high salinity sensitivity. Number of salinity tolerant varieties was decreased with increasing salinity concentration while the salinity sensitive one was increased. Salinity tolerance of some varieties showed the similarity (tolerant or sensitive) under different salinity stresses. Some varieties showed different tolerance under different salinity stresses, i.e. tolerance at low salinity concentration while sensitivity at high salinity concentration.

Effects of harvest date on quality of BNS hybrid wheat flour and steamed bread.

JIANG Xiao-ling, ZHANG Zi-yang, FENG Su-wei, DONG Na, CHEN Xiang-dong, RU Zhen-gang

2013, 24(12):  3495-3500. 

Asbtract ( 1575 )   PDF (399KB) ( 275 )  

Three wheat hybrids derived from the BNS male sterile line were used to study the effect of harvest time on gluten content, dough rheological properties, starch pasting properties of wheat flour and the quality of steamed bread. Each of the three hybrids was harvested at May 27, May 31 and June 4, respectively. The results showed that the flour quality of BNS hybrids was affected by harvest time to some extents, and the best harvest time varied among the different hybrids. For Baiza 1, Baiza 2 and Baiza 3, the best harvest time was May 27, May 27 and June 4, respectively. Both the flour quality and the comprehensive score and taste of steamed bread were the best for the hybrids harvested at these dates. Moreover, Baiza 2 was suited to make steamed bread and noodle when harvested on May 27.

 

Effect of increased temperature in boll period on fiber yield and quality of cotton and its physiological mechanism.

HE Xin-ying, ZHOU Zhi-guo, DAI Yan-jiao, QIANG Zhi-ying, CHEN Bing-lin, WANG You-hua

2013, 24(12):  3501-3507. 

Asbtract ( 1355 )   PDF (472KB) ( 346 )  

To study the effect of temperature increase in boll period (13-Jul. to 24-Aug.) on cotton yield and fiber quality under the global warming background, a pot experiment with cotton cultivar Simian 3 was carried out in halfopentop greenhouse in Pailou experiment station (32°02′ N,118°50′ E) of Nanjing Agricultural University in 2010 and 2011. The results indicated that when the temperature was increased by 2-3 ℃ (with an average daily temperature of 31.1 to 35.2 ℃), the biomass declined by 10%, while the cotton yield declined by 30%-40%. The fiber quality also changed significantly with the relative indices responding differently. The micronaire value and fiber strength increased, the fiber length reduced while the fiber uniformity and elongation rate changed little. The plant photosynthesis capability, the biomass accumulation and the ability of carbohydrates transferring to sink organs all deceased. The soluble amino acids, soluble sugar, sucrose and C/N decreased significantly, while the starch content increased significantly. The allocation in vegetative organs was increased while that in reproductive organs was reduced, which in turn declined the economical index. The lower fruit branches were affected little under increased temperature condition while the middle, upper and top branches were affected greatly. The results indicated that, under the 2-3 ℃ warmer condition, the cotton plants experienced the high temperature stress, both the photosynthesis ability and the carbohydrates transportation from source to sink were decreased, leading to the decline of cotton yield.

Effects of different organic manure sources and their combinations with chemical fertilization on soil nematode community structure in a paddy field of East China.

LIU Ting, YE Cheng-long, CHEN Xiao-yun, RAN Wei, SHEN Qi-rong, HU Feng, LI Hui-xin

2013, 24(12):  3508-3516. 

Asbtract ( 1628 )   PDF (625KB) ( 345 )  

39′41.8″ N, 119°28′23.5″ E) of Jiangsu Province, East China. Six treatments were installed, i.e., no fertilization (CK), 100% chemical NPK fertilization (F),

pig manure compost plus 50% chemical fertilization (PF), straw returning plus 100% chemical fertilization (SF), pig manure compost and straw returning plus 50% chemical fertilization (PSF),  and application of commercial pig manureinorganic complex fertilizer (PMF). The soil samples were collected from the field after the paddy rice harvested in autumn. The two continuous years study showed that the soil nematode community structure varied with fertilization treatments and years. The combined application of chemical fertilizers and organic manures increased the total number of soil nematodes, decreased the abundance of soil bacterivorous nematodes, and made the abundance of predator and omnivore nematodes increased significantly. No significant differences were observed in the abundance of soil fungivorous nematodes among all the treatments. Chemical fertilization alone and the application of commercial pig manure-inorganic complex fertilizer had no obvious suppression effect on the soil phytophagous nematodes. The abundance of soil bacteriavorous nematodes under the combined application of chemical fertilizers and organic manures was relatively increased in the second year, as compared with that in the first year, while the abundance of soil phytophagous nematodes (Hirschmanniella) was relatively decreased in the second year. From the aspect of nematode ecological indices, the Margalef diversity index (H) under the combined application of chemical fertilizers and organic manures in the second year had an increasing trend, while the NCR index had less change. The Wasilewka index  had a relative increase in the second year, while the plant-parasitic index  had a relative decrease. It was suggested that the application of organic manure could increase the abundance of soil microbivorous nematodes, and made the soil environment tend to be healthy.

Detection and analysis of symbiotic bacteria, Arsenophonus and Wolbachia, in striped stem borer, Chilo suppressalis (Lepidoptera: Crambidae).

CHAI Huan-na, WU Hai-yan, DU Yu-zhou

2013, 24(12):  3517-3522. 

Asbtract ( 1599 )   PDF (855KB) ( 362 )  

In this study, 23S rDNA from Arsenophonus and wsp gene from Wolbachia were amplified by PCR method using specific primers to study their symbiosis in Chilo suppressalis from 20 locations of China. The results indicated that Arsenophonus and Wolbachia infection rates differed widely in C. suppressalis populations. The infection rates of Arsenophonus ranged from 5.0% to 50.0% in five geographical populations from Harbin, Huishui, Jilin, Nanyang, and Yangzhou. Wolbachia ranged from 25.0% to 40.0% in three geographical populations from Hanzhong, Nanning, and Yangzhou. Their symbiosis was not observed in C. suppressalis of other locations. The sequences of 23S rDNA gene which named csArs were exactly the same in the five populations. However, the sequences of wsp from the three strains of Wolbachia showed wChisup1 belonged to supergroup A, wChisup5 and wChisup6 belonged to supergroup B. The results showed the strains of Arsenophonus from C. suppressalis of the five different locations were identical, whereas the strains of Wolbachia were phylogenetically diverse. The phylogenetic analysis indicated that 23S rDNA and wsp sequences found in C. suppressalis were exactly the same with or very closely related to relevant sequences in other species.

 

Distribution characteristics of phthalic acid esters in soils and peanut kernels in main peanut producing areas of Shandong Province, China.

CUI Ming-ming1, WANG Kai-rong1,2, WANG Lin-lin1, SHI Yan-xi1

2013, 24(12):  3523-3530. 

Asbtract ( 1463 )   PDF (718KB) ( 354 )  

Surface soil (0-20 cm) and peanut kernel samples were collected in four main peanut producing areas of Shandong Province, and the contents of six PAEs chemicals that classified by the U.S. Environmental Protection Agency as priority pollutants were determined by gas chromatography (GC). The results indicated that the total concentration of six PAEs (∑PAEs) ranged from 0.34 to 2.81 mg·kg^-1, and the mean was 1.22 mg·kg^-1. In four different areas, the order of ∑PAEs concentration in soil was hilly area of middle southern Shandong > western plain of Shandong > Jiaodong Peninsula > northern plain of Shandong. The concentration of DBP in four main peanut producing areas of Shandong Province seriously exceeded the control limit in USA. The content of ∑PAEs ranged from 0.17 to 0.66 mg·kg^-1 in peanut kernels, with the average value 0.34 mg·kg^-1 which was less than the suggested targets in USA and Europe and of low health risk. DEHP and DBP were the main components of PAEs both in soils and peanut kernels, with higher percentage content and detection rate. The ∑PAEs contents in soils or peanut kernels under plastic mulching were significantly higher than that of open field cultivation pattern. The PAEs concentrations in peanut kernels and soils had significant correlation, with the Pearson coefficient 0.786
(∑PAEs), 0.747 (DBP) and 0.511 (DEHP), respectively.

Mercury speciation transformation in soil of the waterlevelfluctuating zone in the Three Gorges Area under alternative dry-wet condition.

ZHANG Cheng1,2, SONG Li1, WANG Ding-yong1，2, ZHANG Jin-yang1, SUN Rong-guo1

2013, 24(12):  3531-3536. 

Asbtract ( 1632 )   PDF (525KB) ( 415 )  

The speciation transformation, influencing factors, as well as bioavailability of mercury (Hg) in soil of the water levelfluctuating zone in the Three Gorges Reservoir Area were simulated. The results showed that Hg in soil under alternative drywet condition could be transformed and released. The total Hg content in the soil was decreased by 28.9% after two “wetdry” cycles. The percentages of the six Hg species (watersoluble, exchangeable, carbonatebound, humicsbound, organicsulf and residual Hg) were 6.1%-16.8%, 5.8%-12.9%, 4.5%-17.7%, 12.5%-29.9%, 5.3%-12.8%, and 34.5%-51.6%, respectively. It was found that Hg in soils was dominantly  residue Hg, whose percentage tended to decrease under alternative drywet condition. The percentage of humicsbound Hg  increased gradually and an increase of the percentage of bioavailable Hg (including watersoluble, exchangeable, carbonatebound, and humicsbound Hg) after two wet-dry cycles were observed. Bioavailable Hg could be easily absorbed by aquatic organisms to enter the food chain, which might increase the ecological risk of Hg in the reservoir.

A field experiment of runoff and sediment yielding processes from residues in Shenfu-Dongsheng Coalfield.

LI Jian-ming1, WANG Wen-long1,2, WANG Zhen3, LUO Ting4, LI Hong-wei5, JIN Jian6

2013, 24(12):  3537-3545. 

Asbtract ( 1283 )   PDF (924KB) ( 509 )  

The processes of runoff and sediment yields from and the benefits of water and sediment reductions by the residues produced in the Shenfu-Dongsheng Coalfield were investigated by a simulated field rainfall experiment. The runoff generation time generally presented a decreasing trend with increasing rainfall intensity, but varied widely with the change of residue compositions. Runoff from the slag reached a steady velocity faster than that from the spoil, and the average velocities of runoff from the residues were gradually decreased in the spoil, the slag with more sand and less stone, and the slag with less sand and more stone. Runoff rates for the residues reached a steady rate 6 min after runoff generation, and were significantly correlated with the rainfall intensities. Erosion on the residues mainly occurred in the first 6 min after runoff generation. Average sediment concentrations in the first 6 min were 0.43-4.27 times of those thereafter for the spoil, and 1.43-54.93 times for the slag. The runoff volume was a linear function of the rainfall intensity for the spoil and the slag with more sand and less stone, and was a power function of rainfall intensity for the slag with less sand and more stone. The relationships between single erosion and rainfall intensity for the spoil and the slag with less sand and more stone can be described by exponential and power functions, respectively. For the spoil, the erosion rate was a linear function of the runoff volume. When fishscale pits and vegetation coverage were adopted on the surface of the slag, the generation of runoff lagged 24 min behind initial rainfall applications at intensities of 1.0 and 1.5 mm·min^-1, and the runoff and sediment yields were reduced by 29.5%-52.9% and 85.7%-97.9%, respectively.

Shrimp community structure and its influential factors in the Jiaojiang River estuary during spring and autumn.

QI Hai-ming1,2, SUN Yue3, XU Zhao-li1, SUN Lu-feng1, GAO Qian1, QUE Jiang-long1, TIAN Wei1

2013, 24(12):  3546-3552. 

Asbtract ( 2313 )   PDF (858KB) ( 435 )  

Based on the data from two oceanographic surveys during April and October 2010, the spatial and seasonal variations in composition, dominance, and diversity of shrimp communities, as well as the influential factors in the Jiaojiang River estuary were analyzed. A total of 16 species of shrimp were found, which belonged to 12 families under 8 genera. 14 species of shrimp were found in spring (April) and 12 species in autumn (October). With the employment of index of relative importance (IRI), in spring 6 dominant species were identified, as Acetes chinensis, Alpheus distinguendus, Parapenaeopsis hardwickii, Leptochela gracilis, Alpheus juponicus and Palaemon gravieri, and in autumn 3 dominant species were found as Solenocera crassicornis,Parapenaeopsis hardwickii and Metapenaeus joyneri. Eurythermal and eurysaline shrimp community prevailed in the Jiaojiang River estuary, followed by eurythermal and hyposaline shrimp community. Margalef index (D), Shannon index (H) and Pielou’s evenness index were used to evaluate the diversity of shrimp community in the studied area. The stations with higher value of D and H were mainly located in the west of the Dachen Island, whereas the Pielou’s evenness index was stable all across the Jiaojiang River estuary. By hierarchical cluster analysis and nonmetric multidimensional scaling (NMDS) method, the results indicated that shrimp communities had significant seasonal and spatial variations. Depth was the most important factor that affected variations in the shrimp community structure in the Jiaojiang River estuary.

Characteristics of net phytoplankton community and their relationships to environmental factors in the waters around Nansha Islands

DAI Ming1, LIU Hua-xue1, LIAO Xiu-li1, LI Kai-zhi2, YAN Jia-guo1, QI Zhan-hui1, HUANG Hong-hui1

2013, 24(12):  3553-3560. 

Asbtract ( 2301 )   PDF (837KB) ( 487 )  

Based on samples collected in the waters around Nansha Islands from August 25 to September 28, 2011, the characteristics of net phytoplankton community and their relationships to environmental factors were investigated. A total of 113 species, belonging to 34 genera of 3 phyla were identified, among which 57.5% belonged to Pyrrophyta and 40.7% belonged to Bacillariophyta. Ceratium in Pyrrophyta had the most species accounting for 30.1% of the 113 species. The average abundance of net phytoplankton was 2.12×10⁴ cell·m^-3 and high abundances were encountered in the complex gyre adjacent to Reed Tablemount and in the Cyclonic Gyre adjacent to Wan’an Tan. Trichodesmium in Cyanophyta was the dominant functional group, taking up 77.0% of the total net phytoplankton abundance. Trichodesmium thiebautii, T. erythraeum and Pyrocystis noctiluca were the major dominant species. The dominant species varied with locations. Cyanophyta widely dominated at stations 3, 5, 6 and 10-14, Pyrrophyta were the dominant phytoplankton in the central locations at stations 4 and 7-9, while Bacillariophyta dominated only at the southernmost stations 1 and 2. The values of Shannon index and Pielou evenness index of net phytoplankton community were 3.10 and 0.62, respectively. The salinity, water temperature, contents of ammonium, nitrite, phosphate and silicate, as well as mesoscale gyres and the west Nansha coastal current were the important environmental factors affecting the characteristics of net phytoplankton community. The ordination plots by canonical correspondence analysis could well display the characteristics of net phytoplankton community and their relationships to environmental factors.

Rapid change in structure of Brachionus calyciflorus complex collected from Jiulian Pond and its ecological mechanism.

NIU Xiang-xiang, XI Yi-long, LI Yao, WANG Ai-ming, LIU Gui-yun

2013, 24(12):  3561-3566. 

Asbtract ( 1212 )   PDF (575KB) ( 367 )  

In order to investigate the rapid variation in the structure of Brachionus calyciflorus complex and the fitness traits of the two sibling species, the rotifers were collected once a week from Jiulian Pond during 16 July and 6 August, their COI genes were sequenced and analyzed, and their fitness parameters (average lifespan, net reproductive rate, intrinsic rate of population increase and proportion of sexual offspring) were calculated at 28 ℃ and 32 ℃ with 1.0×10⁶, 3.0×10⁶ and 5.0×10⁶ cells·mL^-1 of Scenedesmus obliquus as food. In total of 35 samples, 22 haplotypes were defined, among which two distinct lineages (Lineage I and Ⅱ) were revealed by phylogenetic analysis. Sequence divergence was 14.8%-15.6% between the two lineages, indicating the occurrence of two sibling species (sibling species I and Ⅱ). Sibling species Ⅱ occurred only in the second event of sample collection, and its relative abundance in the density of the species complex was lower (1/35). In the population of sibling species Ⅰ, the clones of three shared haplotypes showed overlap, while the others showed displacement. Threeway ANOVA indicated that temperature affected the net reproductive rate, the intrinsic rate of population increase and the proportion of sexual offspring, food level affected the average lifespan, the net reproductive rate and the intrinsic rate of population increase, sibling species affected the average lifespan, the intrinsic rate of population increase and the proportion of sexual offspring. The interaction between temperature and sibling species affected the net reproductive rate and the intrinsic rate of population increase (P<0.05), the interaction between temperature and food level affected the proportion of sexual offspring (P<0.01), and the interaction between food level and sibling species affected the intrinsic rate of population increase of the rotifers (P<0.05). Sibling  species Ⅰ had a higher intrinsic rate of population increase, a shorter average lifespan and a lower proportion of sexual offspring than sibling species Ⅱ.

Effects of diets on growth, serum biochemical indices and lipid metabolism in Coilia nasus fingerlings.

WEI Guang-lian1, XU Gang-chun2, GU Ruo-bo1,2, XU Pao1, 2

2013, 24(12):  3567-3573. 

Asbtract ( 1390 )   PDF (499KB) ( 665 )  

Effects of diets on growth, serum biochemical indices, and enzyme activities related to lipid metabolism in fingerlings Coilia nasus at age of 6 months were investigated during 60-day experiment in this study. Fingerlings with similar body length and mass were fed with one of 3 types of diets (diet 1: soft pellet; diet 2: soft pellet mixed with fish oil; diet 3: slowsinking hard pellet). Fish fed with diets 2 or 3 had significantly higher total body mass, rate of mass gain, specific growth rate, and fullness coefficient than those fed with diet 1. Fish fed with diet 3 exhibited the lower food coefficient compared to those fed with diets 1 or 2. Growth traits (length, length to mass ratio, length to width ratio, hepatopancreas somatic indices and viscera somatic index) and serum biochemical indices (total protein, albumin, blood glucose, cholesterol 〖JP2〗and triglycerides) in all three treatments were not significantly different. Fish fed with diet 1 exhibited significantly higher carnitine palmitoyltransferase-I than those fed with diets 2 or 3, while fish fed with diet 2 exhibited significantly lower carnitine palmitoyltransferase-II. However, amylase, pepsin, lipase activity, lipoprotein lipase and acetyl-coa carboxylase had no significant difference in fish body among all groups. Results suggested that fish oil as a diet supplement highly facilitated fish growing. The slow-sinking pellet had the highest utilization efficiency and was suitable to feed fish fingerlings of C.nasus.

Coupling SWAT and CE-QUAL-W2 models to simulate water quantity and quality in Shanmei Reservoir watershed.

LIU Mei-bing1,2,3, CHEN Dong-ping1, CHEN Xing-wei1,2,3, CHEN Ying1,2,3

2013, 24(12):  3574-3580. 

Asbtract ( 2105 )   PDF (1207KB) ( 469 )  

A coupled watershed-reservoir modeling approach consisting of a watershed distributed model (SWAT) and a two-dimensional laterally averaged model (CE-QUAL-W2) was adopted for  simulating the impact of nonpoint source pollution from upland watershed on water quality of Shanmei Reservoir. Using the daily serial output from Shanmei Reservoir watershed by SWAT as the input to Shanmei Reservoir by CE-QUAL-W2, the coupled modeling was calibrated for runoff and outputs of sediment and pollutant at watershed scale and for elevation, temperature, nitrate, ammonium and total nitrogen in Shanmei Reservoir. The results indicated that the simulated values agreed fairly well with the observed data, although the calculation precision of downstream model would be affected by the accumulative errors generated from the simulation of upland model. The SWAT and CE-QUAL-W2 coupled modeling could be used to assess the hydrodynamic and water quality process in complex watershed comprised of upland watershed and downstream reservoir, and might further provide scientific basis for positioning key pollution source area and controlling the reservoir eutrophication.

 

Assessment of marine environmental stress based on the integrated biomarker response index model: A case study in west coast of Guangxi.

XING Yong-ze, ZHOU Hao-lang, WU Bin, YAN Bing

2013, 24(12):  3581-3587. 

Asbtract ( 2177 )   PDF (805KB) ( 468 )  

Meretrix meretrix were collected for 3 times from 2011 to 2012, at 5 stations along west coast of Guangxi and wild and used as a biological indicator for assessing the marine environmental stress. Six biomarkers at individual, cellular and molecular levels were selected, including time required to drill the sand, phagocytic ability, stability of lysosomal membrane, ferric reducing ability of plasma (FRAP), acetylcholinesterase activity (AChE), and comet rate. Utilizing the Integrated Biological Response Index (IBR) model, the above biomarkers were integratedly analyzed and the data were displayed by intuitionistic star plots to evaluate the environmental situation of the 5 stations. The results indicated that the biological response indices (IBR/n) of the 5 stations varied between 2.30 and 8.68. Maowei Sea had the highest environmental stress, whereas Beilun Estuary had the lowest. Although different biomarkers were different in response to pollution stress, IBR model could effectively distinguish environmental stress of a specific area. The results of biomarker monitoring were basically in agreement with those of chemical monitoring.

Temperature dependence of parameters of plant photosynthesis models: A review.

BORJIGIDAI Almaz1,2,3, YU Gui-rui3

2013, 24(12):  3588-3594. 

Asbtract ( 2472 )   PDF (552KB) ( 612 )  

This paper reviewed the progress on the temperature response models of plant photosynthesis. Mechanisms involved in changes in the photosynthesistemperature curve were discussed based on four  parameters, intercellular CO₂ concentration, activation energy of the maximum rate of RuBP (ribulose1,5bisphosphate) carboxylation (V_{c max}), activation energy of the rate of RuBP regeneration (J_max), and the ratio of J_max to V_{c max}. All species increased the activation energy of V_{c max} with increasing growth temperature, while other parameters changed but differed among species, suggesting the activation energy of V_{c max} might be the most important parameter for the temperature response of plant photosynthesis. In addition, research problems and prospects were proposed. It’s necessary to combine the photosynthesis models at foliage and community levels, and to investigate the mechanism of plants in response to global change from aspects of leaf area, solar radiation, canopy structure, canopy microclimate and photosynthetic capacity. It would benefit the understanding and quantitative assessment of plant growth, carbon balance of communities and primary productivity of ecosystems.

Effects of elevated atmospheric CO₂ on plant, herbivorous insect, and its natural enemy: A review.

XIE Hai-cui1, CAI Wan-zhi2, WANG Zhen-ying1, HE Kang-lai1

2013, 24(12):  3595-3602. 

Asbtract ( 1406 )   PDF (501KB) ( 574 )  

Since the industrial revolution, the huge consumption of fossil fuels and unduly destruction of natural habitats by human activities have led to the everincreasing concentration of atmospheric CO₂. To study the adaptation mechanisms of plant, herbivorous insect, and its natural enemy within agricultural ecosystems to the elevated atmospheric CO₂ concentration is of significance in deciphering the damage pattern of agricultural pest occurrence and controlling the pest occurrence  and in mitigating the CO₂ emission from agricultural ecosystems. This paper reviewed the research progress on the effects of elevated atmospheric CO₂ on the host plant, herbivorous insect, and its natural enemy in agroecosystem, with the focuses on the improvement of related research methods, the variation patterns of host plant primary and secondary metabolites induced by elevated atmospheric CO₂, the effects of the elevated CO₂ on the growth and development, population density, and behaviors of herbivorous insect, and the biology and predation and/or parasitism rates of natural enemy. The future research frontiers in this research area were also discussed.

Measurement and estimation methods and research progress of snow evaporation  in forests.

LI Hui-dong1,2, GUAN De-xin1, JIN Chang-jie1, WANG An-zhi1, YUAN Feng-hui1, WU Jia-bing1

2013, 24(12):  3603-3609. 

Asbtract ( 1903 )   PDF (453KB) ( 413 )  

Accurate measurement and estimation of snow evaporation (sublimation) in forests is one of the important issues to the understanding of snow surface energy and water balance, and it is also an essential part of regional hydrological and climate models. This paper summarized the measurement and estimation methods of snow evaporation in forests, and made a comprehensive applicability evaluation, including mass-balance methods (snow water equivalent method, comparative measurements of snowfall and through-snowfall, snow evaporation pan, lysimeter, weighing of cut tree, weighing interception on crown, and gamma-ray attenuation technique) and micrometeorological methods (Bowenratio energybalance method, Penman combination equation, aerodynamics method, surface temperature technique and eddy covariance method). Also this paper reviewed the progress of snow evaporation in different forests and its influencal factors. At last, combining the deficiency of past research, an outlook for snow evaporation rearch in forests was presented, hoping to provide a reference for related research in the future.

Effects of vegetation restoration on soil carbon and nitrogen cycles: A review.

WENG Bo-qi1, ZHENG Xiang-zhou2, DING Hong2, WANG Huang-ping2

2013, 24(12):  3610-3616. 

Asbtract ( 2394 )   PDF (470KB) ( 781 )  

Vegetation rehabilitation is one of the main means in managing soil and water loss, being able to effectively promote the development of eroded soil, improve the soil fertility level, enhance the soil microbial activities, and in further, affect the soil carbon and nitrogen cycles. Therefore, vegetation rehabilitation plays definite roles in the accumulation of soil organic carbon and nitrogen pools and the mitigation of greenhouse gases emission from soil. This paper summarized the effects of vegetation rehabilitation on the soil carbon and nitrogen cycles and the synergetic effects between soil quality and vegetation rehabilitation, and put forward the further research directions, which could provide the reference for the evaluation of the roles of vegetation rehabilitation in response to global climate change, and the practical guidance for the improvement of soil fertility and the recovery and sustainable development of degraded ecosystems.

 

Research progress in microbial methane oxidation coupled to denitrification.

ZHU Jing1, YUAN Meng-dong1, LIU Jing-jing2, HUANG Xiao-xiao1, WU Wei-xiang1

2013, 24(12):  3617-3624. 

Asbtract ( 3148 )   PDF (498KB) ( 485 )  

Methane oxidation coupled to denitrification is an essential bond to connect carbon and nitrogen cycling. To deeply research this process will improve our understanding on the biochemical cycling of global carbon and nitrogen. As an exogenous gaseous carbon source of denitrification, methane can both regulate the balance of atmospheric methane to effectively mitigate the greenhouse effect caused by methane, and reduce the cost of exogenous carbon source input in traditional wastewater denitrification treatment process. As a result, great attention has being paid to the mechanical study of the process. This paper mainly discussed the two types of methane oxidation coupled to denitrification, i.e., aerobic methane oxidation coupled to denitrification (AME-D) and anaerobic methane oxidation coupled to denitrification (ANME-D), with the focus on the microbiological coupling mechanisms and related affecting factors. The existing problems in the engineering application of methane oxidation coupled to denitrification were pointed out, and the application prospects were approached.