Table of Content

10 September 2008, Volume 27 Issue 09

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Articles

Spatiotemporal variation pattern of vegetation’s net primary productivity in China.

HOU Ying-yu^1,2；MAO Liu-xi¹；LI Chao-sheng¹;QIAN Sh-uan¹

2008, 27(09):  1455-1460 . 

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Based on the remote sensing and climatic data from 1982 to 2000 and byusing statistical analysis, the spatiotemporal variation pattern of vegetation’s net primary productivity (NPP) in China was studied. In the 20 years, only 8% of the land had a marked decrease of the NPP, 47% of the land was in adverse, while approximately 44% of it had little change. The annual vegetation’s NPP increased in most parts of the country but decreased in its eastern developed provinces or industrialized and urbanized regions, and, there existed obvious spatial differences in the variation rate of the annual vegetation’s NPP. The inter-annual relative variability of vegetation’s NPP was smaller in most parts of China, but greater in the desert grassland area of northwestern China.

Relationships between spring phenology of Shenyang urban forest and global climate warming in last 40 years.

XU Wen-duo¹;HE Xing-yuan¹;CHEN Wei¹; LIU Chang-fu²;ZHAO Gui-ling²;ZHOU-Yuan²;WEN Hua¹

2008, 27(09):  1461-1468 . 

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In last 40 years (1960-2005), the spring phenology of Shenyang urban forest was affected by global warming. The mean annual air temperature of Shenyang had an overall increase, with the increment being 0.96 ℃. Before 1982, it was relative cold and the maximal of the decrease was 1.95 ℃;while after 1982, it was relative warm and the maximal increment was 1.60 ℃. The air temperature was increased in the whole year, with the maximal increment in winter (2.3 ℃) and spring (1.35 ℃). The spring phenological phase of main tree species in Shenyang urban forest presented itself later in relatively cold period, but in advance in the relatively warm period. The dates of the beginning and ending of the spring phenological phase had a close synchronous relationship, and correlated negatively with the length of the seasonal rhythm of phenology. There was a significant negative correlation between the date of budding and the air temperature in winter and early spring. The higher the air temperature in winter and early spring, the earlier the tree budded. The date of sprouting new leaves was mainly affected by the air temperature in spring and had less correlation with the temperature in winter, while that of early flowering was mainly affected by the air temperature 20-80 days (especially 20-40 days) before early flowering.Coldness index (CI) had significant positive correlations with the dates of budding and sprouting new leaves, but less correlation with the date of early flowering. It was predicted that under the conditions of elevated CO₂ concentration and air temperature, the dates of budding, sprouting new leaves, and early flowering of the main tree species in Shenyang urban forest would be advanced for 40.41, 43.08, and 24.13 days, respectively.

Effects of environmental factors on soil organic carbon mineralization in a Pinus sylvestris var. mongolica plantation.

WANG Hong^1,2;FAN Zhi-ping¹;DENG Dong-zhou^1,2;CHEN De-long³;SUN Xue-kai¹;GAO Jun-gang^1,2;ZENG De-hui¹

2008, 27(09):  1469-1475 . 

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Soil organic carbon mineralization is the major pathway of soil carbonrelease into atmosphere. To investigate the relationships between soil organic carbon mineralization and environmental factors is of significance in studying global carbon cycle and its potential feedback to climate change. With incubation test, this paper studied the effects of temperature, soil moisture, and carbon and nitrogen addition on the mineralization rate of soil carbon (C_min) in a 10-year old Pinus sylvestris var. mongolica plantation at Keerqin Sandy Lands. The results indicated that the C_min increased xponentially with the temperature from 10 ℃ to 30 ℃, and positively linearly increased with soil moisture content from 10% water hold capacity (WHC) to 100% WHC. The dependence of soil carbon mineralization to temperature (Q₁₀) was different under different soil moisture conditions. When the soil moisture content was 10% WHC, the Q₁₀ value was the smallest. The sensitivity of soil carbon mineralization to soil moisture content was significantly lower at low temperature (10 ℃) than at suitable or high temperature (20 ℃-30 ℃). Carbon addition increased the C_min, while nitrogen addition had less effect. However, with the increase of soil organic carbon content, the C_min was affected by soil nitrogen content.

Analysis and forecast of lifecycle of forest ecotourism area: A case study of Wulingyuan scenic spot.

DONG Cheng-sen¹;XIONG Ying²;ZOU Dong-sheng¹

2008, 27(09):  1476-1481 . 

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Resort lifecycle theory has been one of the hot issues. The researcheson the lifecycle have involved in various types of tourism areas in China, but those on forest ecotourism area are few. Based on Butler’s resort lifecycle theory, this paper analyzed the characteristics of the lifecycle of Wulingyuan scenic spot, a famous forest ecotourism scenic spot in China, aimed to provide a scientific support for Wulingyuan’s tourism development. The results indicated that Wulingyuan scenic spot was at the stage of stable development. The number of tourists till 2010 would reach 27.53845-36.58907 millions. The development strategies of extending Wulingyuan scenic spot lifecycle were put forward.

Root nodulation of young Alnus formosana on forest lands converted from agricultural lands.

PAN Yan; LI Xian-wei; RONG Li; YUAN Wei-yang; WANG Jing

2008, 27(09):  1482-1486 . 

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Root nodulation can directly reflect forest nitrogen-fixing ability, and is an important content in root study. Some profitable suggestions about forest fertilization and management would be offered by studying the forest nodulation on the lands converted form agricultural lands. In this paper, the root nodulation of young Alnus formosana and its relations with soil nutrients on four forestlands converted from agricultural lands in Sichuan Province were studied. The results showed that the root nodules of young A. formosana at the four sites had the same coral-shaped appearance and a compact structure, with the minimum and maximum diameter being 2 and 30 mm, respectively. The biomass of the root nodules varied from 2.59 to 132.14 g per plant. The horizontal distribution of the nodules was less than 50 cm from A. formosana stem, and their vertical distribution was concentrated in 0-20 mm soil layer. 50.45%-92.5% of the nodules were accreted to fine root (d≤2 mm), but large volume root nodules were accreted to root crown. Correlation analysis showed that root nodule biomass was significantly negatively correlated with soil hydrolytic N, but significantly positively correlated with soil available P (P＜0.05).

Physiological responses of Guadua amplexifolia to NaCl stress.

MA Lan-tao;CHEN Shuang-lin

2008, 27(09):  1487-1491 . 

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A pot experiment was conducted with 2-year-old Guadua amplexifolia to study its NaCl tolerance. The results indicated that NaCl stress had significant effects on the physiological and biochemical characteristics of the plant. The salt injury was divided into 3 degrees, based on the leaf-abscission rate after 40-days exposure, i.e., noninjury (<10%), mild injury (10%-50%), and serious injury (>50%). The ion leakage and MDA content increased considerably over time, the relative conductivity of the plant exposed to 0.30% and higher salinity for 40 days was >50%, and the MDA content was higher than that at lower salinity. Both POD and SOD activities increased in the early days and then decreased with extended NaCl exposure. On the 40th day exposure, POD activity was the highest at 0.20% NaCl, while SOD activity was the highest at 0.30% NaCl. Osmoregulation substance such as free proline and soluble protein had the same trend. After 40 days exposure, the contents of free proline and soluble protein kept increasing in the plants exposed to 0.20% and lower salinity, while kept decreasing in those exposed to 0.30% and higher salinity. In summary, 0.30% and higher soil salinity was not suitable for the growth of G. amplexifolia.

Responses of winter wheat extraordinary flourishing in autumn on Loess Plateau in eastern Gansu to climate warming.

WANG Wei-tai^1,2;ZHANG Tan-feng²;MA Peng-li³;PU Jin-yong⁴;Lü Feng-ping²;HUANG Bin²

2008, 27(09):  1492-1497 . 

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Based on the parallel observation in experimental fields in Xifeng City of Gansu Province, the climatic characteristics of winter wheat extraordinary flourishing on Loess Plateau of eastern Gansu in 2006 and the responses of many years winter wheat’s autumn growth to climate warming were analyzed. The results showed that the winter wheat extraordinary flourishing in autumn 2006 was an event with relatively smaller probability. When the mean air temperature in October was ≥10.0 ℃, the winter wheat height growth in autumn increased obviously with increasing air temperature; and when the accumulated temperature of ≥10.0 ℃ achieved above 580 ℃, the height growth increased obviously with increasing accumulated temperature. When the mean air temperature in October ascended by 1 ℃, the leaf area index increased by 0.4; and when the accumulated temperature of ≥10.0 ℃ achieved above 550 ℃, the leaf area index increased obviously with increasing accumulated temperature. The numbers of big tiller increased in counter-parabola shape with the increasing mean air temperature in October and accumulated temperature of ≥10.0 ℃. In order to actively control the winter wheat extraordinary flourishing before winter and to reduce the unreasonable consumption of soil moisture and nutrients, autumn sowing should be postponed about 5 days, so as to positively and effectively reduce the negative effects of climate warming on winter wheat growth.

Enrichment characteristics of Cd, Pb and Cr in Procambarus clarkia tissues.

ZHOU Li-zhi;CHEN Chun-ling;ZHANG Lei;QIU Wen-na;YU Zhen-wei;YANG-Qian

2008, 27(09):  1498-1502 . 

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Thirty individuals of red swamp crayfish (Procambarus clarkia) were collected from the ponds and rivers in Hefei City, Feixi County, and Feidong County of Anhui Province in May 2005, and the residual amounts of Cd, Pb and Cr in a total of 84 ectoskeleton, liver, and muscle samples were determined by atomic absorption spectrophotometry. The results showed that the average detection rates of Cr, Cd and Pb in the samples were 100%, 91.7% and 94.1%, and the average concentrations of these heavy metals were 4.03, 0.38 and 7.14 μg·g^-1, respectively. Among the three test tissues, no significant difference was observed in Cr enrichment, but the enrichment of Cd and Pb was significantly different. The average concentrations of Cr, Cd and Pb in ectoskeleton, liver, and muscle were 4.03, 0.12 and 12.31 μg·g^-1, 3.88, 1.04 and 9.12 μg·g^-1, and 4.16, 0.09 and 0.72 μg·g^-1, respectively. Among the three test sites, there existed significant differences in the enrichment of Cr in ectoskeleton and muscle, and of Cr, Cd and Pb in liver. The enrichment of test heavy metals had no notable correlation with the body mass of P. clarkia, and no significant difference was found in the enrichment of the heavy metals between female and male individuals.

Population dynamics, annual production, and trophic basis of dominant chironomids in Tanqigou Stream.

JIANG Jing;WEN Fang-ni;SU Hua-wu;LI Xiao-yu;HE Peng;YAN Yun-jun

2008, 27(09):  1503-1509 . 

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An investigation on the population dynamics, annual production, and trophic basis of dominant chironomids in the macrozoobenthos community in a second order river (Tanqigou Stream) of Qingjiang River Basin was conducted from April 2006 to March 2007. The results showed that all of the three dominant chironomids Thienemanimyia lentiginosa, Eukiefferiella potthasti and Paratanytarsus parthenogeneticus developed two generations per year. The population density of P. parthenogeneticus and T. lentiginosa reached the peaks in June, September and next January, while that of E. potthasti attained the peaks in May and next January. The annual production (in wet mass) and its ratio to biomass of the three chironomids estimated by instar frequency method were 17.44 g·m^-2 and 3.4 for T. lentiginosa, 1.66 g·m^-2 and 2.3 for E. potthasti, and 3.3 g·m^-2 and 6.4 for P. parthenogeneticus, respectively. The temporal overlap of the production among the three chironomids was relatively large in spring. The proportions of various food types and their contribution to the production were estimated by foregut content analysis, showing that amorphous detritus was the most important food type, accounting for 73.27%–86.89% of the foregut content of E. potthasti and P. parthenogeneticus, while animal material contributed 51.64% to the production of T. lentiginosa.

Distribution characteristics of medusa in Yangtze River Estuary and its adjacent waters in summer.

LUN Feng-xia^1,2;WANG Yun-long²;SHEN Xin-qiang²;XU Hou-lian³

2008, 27(09):  1510-1515 . 

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Based on the investigations at the Yangtze River Estuary and its adjacent waters (121°15′E-122°41′E, 30°00′N-31°30′N) in August of 1998 and 1999, the distribution characteristics of medusa and their affecting factors were studied. A total of 21 medusa species including 15 of Hydromedusae, 4 of Siphonophore, and 2 of Ctenophore were identified, which could be classified into three ecological groups, i.e., low salinity neritic group, low salinity estuarine group, and oceanic warm water group. The first group distributed widely, the second group was more prevalent in lower salinity estuary, and the third one only appeared in higher salinity offshore area. The dominant species were Nemopsis bachei, Pleurobrachia globosa, Clytia folleata, Muggiaea atlantica, Lensia subtiloides, and Diphyes chamissonis. With the increase of salinity from the Yangtze River Estuary to the offshore, the abundance of medusa increased gradually, being the highest in western Zhoushan Fishing Ground where the waters from the Yangtze River and open sea were mixed together. Water mass had significant effects on the distribution of medusa. The more severe the open seawater invaded,the higher the abundance of medusa was. In contrast, when the whole area was under the control of diluted water from Yangtze River, the abundance of medusa was lower.

Population dynamics of cotton spider mite (Tetranychus turkestani) under different irrigation systems.

DANG Yi-chun;ZHANG Jian-ping;TAN Yong-fei; FENG Xiao-hui

2008, 27(09):  1516-1519 . 

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This paper studied the effects of drip- and furrow irrigation and of different irrigation amount and period under drip irrigation on the occurrence of cotton spider mite Tetranychus turkestani in Xinjiang cotton field. The results showed that both irrigation method and irrigation amount had definite effects on the T. turkestani occurrence. Furrow irrigation was favorable to the occurrence of T. turkestani, while drip irrigation was in adverse. Under drip irrigation, when the irrigation amount was much higher or lower than the normal, the occurrence of T. turkestani was promoted, the occurrence peak appeared earlier, and the individuals were more. Different drip irrigation period had no significant effects to the occurrence of T. turkestani.

Genetic diversity of seven Onthophagus gibbulus (Coleoptera: Scarabaeidae) populations in middle part of Inner Mongolia.

ZHANG Cai-xia;TAI Li-hua;LIU Xin-min

2008, 27(09):  1520-1525 . 

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By the random amplification polymorphism DNA (RAPD) molecular technique, the genetic diversity and genetic differentiation of seven Onthophagus gibbulus populations in the middle part of Inner Mongolia were analyzed. RAPD amplification was conducted with 16 primers, and 363 polymorphic loci were detected, with the percentage of polymorphic loci being 100%. The total Nei’s gene diversity was 0.280, and the Shannon’s information index was 0.433, indicating a high level of genetic diversity of O. gibbulus. The among population component accounted for 12.57% of the total variation, while the within-populations component accounted for 87.43%. The genetic differentiation among the populations was relatively low, with the G_st being 0.074-0.203, and the gene flow value (N_m) among the populations was 4.569-9.791, which indicated a strong gene flow among the populations. No correlation was observed between the populations’ genetic variation and geographic distance, suggesting that the populations’ differentiation was affected by the heterogeneity of habitat.

Mercury concentration and distribution in Locusta migratoria manilensis in Huludao City of Liaoning Province, China.

ZHANG Zhong-sheng^1,2;WANG Qi-chao¹;ZHENG Dong-mei^1,2;TIAN Li-xin³;ZHENG Na^1,2;ZHANG Xiu-wu^1,2;ZHANG Xin-yan^1,2;ZHANG Shao-qing⁴

2008, 27(09):  1526-1530 . 

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Locusta migratoria manilensis samples were collected from Huludao City of Liaoning Province, and the mercury concentration and distribution in their different organs were studied. The results showed that the mercury concentration in L. migratoria manilensis was relatively high, being 0.33-174.86 ng·g^-1, with an average of 36.44 ng·g^-1. The total concentration of mercury in L. migratoria manilensis and its different organs was significantly negatively correlated with its body length and mass, and decreased in the order of wing>head>abdomen>thorax≈leg. The absolute mercury concentration in L. migratoria manilensis increased with body mass, but decreased due to biomass dilution. Mercury was mainly accumulated in the head and wing of L. migratoria manilensis. The biomass dilution and mercury accumulation in wing might be the important mechanism of L. migratoria manilensis in resisting mercury hazard.

Prediction of spatial distribution of Eupatorium adenophorum Sprengel based on GARP model: A case study in Longitudinal RangeGorge Region of Yunnan Province.

LI Shuang-cheng;GAO Jiang-bo

2008, 27(09):  1531-1536 . 

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The invasion of Eupatorium adenophorum Sprengel may occupy the living space of other plant species, reduce the native biodiversity and ecosystem productivity, and cause serious ecological consequences. To reasonably estimate the potential hazards of this invasion and adopt corresponding measures, it’s necessary to investigate the invaded region and potential distribution of the weed. Based on the distribution data of E. adenophorum and related environmental factors in Longitudinal Range-Gorge Region of Yunan Province, and by using Genetic Algorithm for Rule-set Prediction (GARP) model, the potential distribution of the weed was predicted. The results showed that the main suitable area for E. adenophorum was the south part of the study region, where the suitable distribution index was above 0.5, except for some specific sites. Due to the high elevation and low air temperature, the suitable distribution index in the north part of the region, except some valleys, was much lower. The modeling results of artificial neural network were basically consistent with the GARP model, showing a higher suitable distribution index in the south than in the north part. Some mountainous areas in the south part and most areas in the north part of the region were not suitable for the growth of E. adenophorum.

Sexual reproductive characteristics of Spartina alterniflora Loisel. in Tianjin coastal wetland.

YUAN Ze-ning;SHI Fu-chen;LI Jun-jian;GUO Shi-yi

2008, 27(09):  1537-1542 . 

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An investigation was made on the reproductive traits such as flowering, pollination, and seed-setting of smooth cordgrass (Spartina alterniflora Loisel.) in Tianjin coastal wetland. The results showed that the flowering of the grass initiated in mid-August, and senescence occurred by the end of October. S.alterniflora was a wind-pollinated grass, which was revealed by the adaptation of higher pollen/ovule ratio (P/O) (9874.67±2149.39) and the small pollen grains. Pollen viability presented an exponential downtrend with the time of pollen release, and the character of stigma adapted to capturing pollen grains. The exterior pollen tube growth following pollination showed the high capability of pollen germination. The average seed-setting rate was （67.56±2.39）% and the seed germination rate was above 80%, which was important for the population colonization and recruitment.

Niches of alien weeds in main habitats of Kaifeng suburb.

LI Jun-jiao²;GU Yan-fang^1,2;ZHANG Li-xia²;DING Sheng-yan^1,2

2008, 27(09):  1543-1548 . 

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In spring and autumn of 2005, the alien weeds in various habitats of Kaifeng suburb, including farmland, orchard, vegetable garden, and wasteland, were investigated, and the niche breath and overlap of the alien weeds and main native weeds were measured. A total of 11 alien weed species were recorded, 7 species occurring in spring, 7 species in autumn, and 3 species in both seasons. In spring, the relative abundance of Veronica didyma and Conyza canadensis was higher, being 0.239 and 0.111, respectively; in autumn, Cyperus rotundus had a higher relative abundance, being 0.409. In spring, C. Canadensishad a wider niche breath (0.854); in autumn, the niche breath of Eleusine indica, Amaranthus retroflexus, and C. rotundus was 0.986, 0.822, and 0.807, respectively. The niche overlap values of alien and native weeds were mainly under 0.5, and there existed polarizations in utilizing resources between them. The alien weeds had advantages in population expansion.

Characteristics of community structure of planktonic algae in Gehu Lake of Jiangsu Province.

CHEN Li-jing¹;PENG Zi-ran²;KONG You-jia³;HUA Shao-peng³;GU Jing¹;WANG Wu¹

2008, 27(09):  1549-1556 . 

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The community structure and species diversity of planktonic algae in Gehu Lake of Jiangsu Province were investigated from April 2004 to January 2006, and their relationships with the physicochemical parameters of the lake were analyzed. A total of 267 planktonic algae species belonging to 8 phyla and 147 genera were identified, among which, Chlorophyta (130) was the dominant, followed by Bacillariphyta (59) and Cyanophyta (36). The dominant species were Microcystis aeruginosa, M. incerta, Merismopedia punctata, M.tenuissima, Rhabdoerma lineare, and Goelastrum microporum. The mean annual total algal density and biomass were 4 871.09×10⁴ and 7.302 mg·L^-1, respectively. The density was the highest in autumn, and the biomass was higher in spring and autumn than in other two seasons. The biodiversity reached the maximum in spring, and was related positively to algal density but negatively to algal biomass. The standing crop of planktonic algae decreased gradually from the north to the south area, with significant difference between these two areas but no significant differences between the north and middle area and the middle and south area.

Fractal characteristics and related affecting factors of particle size distribution in mangrove soils in Dongzhai Harbor of Hainan.

LIU Mei-ling;YE Yong;CAO Chang-qing;TANG Fei-long

2008, 27(09):  1557-1561 . 

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The analysis with fractal theory on the fractal characteristics and related affecting factors of particle size distribution in mangrove soils in Dongzhai Harbor of Hainan showed that the fractal dimension of mangrove soils ranged from 2.302-2.575. There was a significant positive linear relationship between the fractal dimension and the contents of soil clay, salts, organic matter and total nitrogen. The fractal dimension was lower in outside beach than in middle and inner beach, and changed with soil texture, being in the order of sandy loam<light loam<medium loam<heavy loam. From land to sea, the fractal dimension decreased gradually. The main factors affecting the fractal dimension were community type, soil texture, beach position, soil salinity, and organic matter and total nitrogen contents.

Effects of climate warming on seasonal frozen soil in east Gansu.

PU Jin-yong^1,2;WANG Wei-tai³;YAO Xiao-ying⁴;WANG Yan-ling³

2008, 27(09):  1562-1566 . 

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Under the effects of climate warming, the freezing, thawing, and their durations of seasonal frozen soil changed greatly. By using the 1971-2005 observation data collected from eight weather stations in east Gansu, the effects of climate change in east Gansu on the seasonal frozen soil of this region were studied. The results showed that since 1970s, the wintertime air temperature of this region raised by 2.7 ℃, freezing and thawing dates of soil in a thickness of 30 cm shifted 10 days later and earlier, respectively, freezing duration shortened by about 20 days, and the maximum frozen depth decreased by about 20 cm. With persistent climate warming, the maximum frozen depth would be decreased continuously, and it was predicted that in 2050, the decrement would be at least about 15 cm, which would have greater effects on the design and construction of engineering.

Succession grading and trend forecasting of waterlogged lowland in Fourlake region of Jianghan Plain.

LIU Zhang-yong;HE Hao

2008, 27(09):  1567-1570 . 

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To study the succession pattern of waterlogged lowland is the theoretical basis of making countermeasures for ecological restoration of waterlogged lowland. In this paper, the Delphi method was used to determine the indices of evaluating the succession grading series of the waterlogged lowland in Four-lake region, including dominant plant populations, cultivated living things most quickly increased in the region, area percentage of waterlogged lowland to all farmland, groundwater table of waterlogged lowland, and stability of organic matter oxidization in soil. The evaluating standard of each index was then established. As a case, an expert information database on the succession of the waterlogged lowland in Honghu City was built, and the succession grading series in the City was obtained. ARIMA model was used to fit and forecast the succession grading series of the waterlogged lowland in Honghu City, and the result showed that this model was better in fitting and forecasting the change trend of succession grading of waterlogged lowland.

Effects of Exserohilum monoceras crude toxin on the physiological activities of Echinochloa crusgalli.

ZHENG Wei¹;CHEN Yong¹;CUI Hai-lan²;ZHANG Hong-jun³;TAN Wei-jun¹; YU Te¹

2008, 27(09):  1571-1575 . 

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The crude toxin was extracted from Exserohilum monoceras X27, and its effects on the inhibition of seed germination, radical growth, embryo growth, and seedling growth of Echinochloa crus-gallias well as the chlorophyll content, superoxide dismutase (SOD) activity, malondiadehyde (MDA) content, and relative electrical conductivity (EEC) of E. crus-galli leaves at 2nd-leaf stage were studied by the methods of filter paper, detached leaf, and spot-spraying. The results showed that the toxin at 5.0 g·L^-1 strongly inhibited the seed germination, radical growth, and embryo growth, and made the detached leaves before 4th-leaf stage completely dead. The crude toxin also strongly affected the growth of plants at 1st- and 2ndleaf stages. On the 7th day after spraying toxin, the inhibition rate of seedling height exceeded 20%; while on the 28th day, the mass inhibition rate of above- and underground parts exceeded 40% and 70%, respectively. Within the 7 days of spraying the toxin, the chlorophyll content of 2nd leaf stage plants decreased significantly, while MDA content, SOD activity and EEC were in adverse.

Effects of pH, alkali type, and preequilibration duration on the long term stability of ironarsenic coprecipitate.

Lü Hong-tao^1,2;JIA Yong-feng¹;YAN Hong³;CHEN Liang¹ 

2008, 27(09):  1576-1579 . 

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Coprecipitation of As(Ⅴ) with Fe(Ⅲ) is a widely used economical method for the removal of arsenic from mineral-processing solutions and effluents. To prevent secondary pollution, the stability of arsenic-bearing precipitates should be further studied. With simulation test, the stability of ironarsenic precipitate was investigated as a function of pH, alkali type, and preequilibration duration at pH 4. The results showed that at pH 4, the precipitate had the highest stability, and the stability was increased with the duration of preequilibration. The addition of lime or Ca²⁺ could markedly increase the stability of arsenic in the precipitate.

Impacts of Pb²⁺ and Cr⁶⁺ on the photosynthesis and quality of Ipomoea aquatica Forsk. under simulated acid rain.

ZHEHG You-fei;LI Lu;LIANG Jun

2008, 27(09):  1580-1586 . 

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A pot experiment was conducted to study the impacts of Pb²⁺ and Cr⁶⁺ on the photosynthesis, nutritional quality, and food safety of water spinach (Ipomoea aquatica Forsk.) under simulated acid rain (AR) with different acidity. The results showed that under AR, the stress of test heavy metals on the photosynthesis and quality of the spinach decreased in the order Pb>Pb+Cr>Cr. With increasing acidity of AR, the impact of treatments AR+Pb and AR+Pb+Cr increased remarkably, and the stress effect of treatment AR+Pb+Cr was greater than that of the other treatments under pH=3.5. Compared with the control, three parameters of photosynthesis decreased with increasing acidity of AR, but had different susceptivity to the stress. The protein and free amino acid contents in the spinach had positive correlations with pH when the pH was <5.6, and, with increasing acidity, the soluble sugar content increased while reductive sugar content decreased, being a kind of response to the environmental stress. Treatments Pb and Pb+Cr notably promoted the nitrate nitrogen accumulation, and the nitrate nitrogen content in the spinach increased with the acidity of AR. There existed a competition between the adsorption of Pb and Cr in the spinach, and the enrichment of the two heavy metals would be sped up with decreasing acidity of AR.

Residual of organic pesticides in single axile dispersal type shootusing bamboo shoot.

GUO Zi-wu¹;CHEN Shuang-lin¹;YANG Qing-ping¹;GU Li-jian²;XIAO Jiang-hua¹

2008, 27(09):  1587-1591 . 

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Bamboo shoot samples were collected from 28 plots in the bamboo forests in 4 counties of Zhejiang Province to investigate the residual of organic pesticides. Three kinds of organochlorine pesticides, i.e., BCH, DDT, and pentachlornitrobenzene (PNCB), were detected. The detection rate of both BCH and DDT was 100%, and that of PNCB was 75%. None of pyrethroid and organophosphorus pesticides were detected. The average residual of all test organic pesticides was lower than 50 μg·kg^-1. The Nemerow index showed that the shoot samples could be divided into two types, i.e., safety shoot, accounting for 82.14%, and basic safety shoot, accounting for 17.86%. It was suggested that the residual of organochlorine pesticides in bamboo shoots from Zhejiang Province was universal, but not severe. In addition, management level, management type, and land use pattern had definite effects on the residual of organochlorine. The pesticide residual pattern in shoots was similar to that in bamboo soil.

Preparation and purification of cadmium-induced antiserum against cucumber-metallothionein.

WANG Ting-pu;AN Jian-ping;ZOU Ya-li;MA Teng;ZHANG Chun-cheng

2008, 27(09):  1592-1595 . 

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The metallothionein (MT) was produced with cucumber leaves under treatment of cadmium. After purification, the MT was coupled with BSA, and then injected subcutaneously or intracutaneously into the back and auricular vein of rabbit to generate antibodies against MT. The measurement showed that the ratio of antibody was 1 to 16. IgG was isolated and purified by (NH₄)₂SO₄saturated precipitation and Sephadex G-200 column. The content of IgG was up to 0.9364 mg·ml^-1 through UV determination. Dot-immunobinding assay revealed that the minimal level of antigen detected by Cd-MT antibody was 200 pg·ml^-1.

Ecological footprint and water footprint of Dalian City.

TAI Shan-shan^1,2;ZHANG Wei-dong³;U Yuan-man¹; LIU Miao¹

2008, 27(09):  1596-1600 . 

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Ecological footprint (EF) model has been widely used in evaluating sustainable development and ecological capacity (EC). Based on the statistics of Dalian City, its EF per capita and EC per capita were calculated to evaluate the ecological sustainable development of the city. In the meantime, the water footprint of the city in 2001 was analyzed by using water footprint approach. The results showed that from 1991 to 2004, the ecological footprint per capita of Dalian had an overall increase, with the mean EF being 2.250 hm² per capita or more. The EF was 2.250 hm² per capita in 1991 and 3.965 hm² per capita in 2004, and there existed different level ecological deficit from 2000 to 2004. The water footprint in 2001 was 748.270 m³ per capita, being lower than the mean level of North China, suggesting that Dalian City belonged to water deficit area.

Response mechanisms of soil carbon and nitrogen decomposition to temperature change.

WU Jian-guo;Lü Jia-jia

2008, 27(09):  1601-1611 . 

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The response of soil carbon and nitrogen decomposition to temperature change is crucial for the impact of climate change on terrestrial ecosystem carbon sink. In this paper, the mechanisms and hypotheses about the effects of temperature change on the decomposition of soil carbon and nitrogen were reviewed. The mechanisms mainly include the functions of the stability, quality, and availability of soil organic matter (SOM), the biomass, activity, community structure, and diversity of soil microbes, the water content in soil, the productivity of vegetation and litter, and the soil pH. There are still uncertainties for the mechanisms about the effects of temperature change on the decomposition of soil carbon and nitrogen, and it is necessary to consider the SOM fractions with different stability, the features of microbes, the interactions between SOM fractions and soil microbial features, and the differences of the longterm and shortterm responses of soil carbon and nitrogen decomposition to temperature change. The hypotheses about the effects of temperature change on the decomposition of soil carbon and nitrogen include carbon qualitytemperature hypothesis, physical-chemical hypothesis, and functional shift hypothesis. Further researches and experiments are necessary to test and improve these hypotheses.

Typical patterns on the relationships between protected areas and local communities.

LIU Jing;MIAO Hong;OUYANG Zhi-yun;LI Xiao-guang

2008, 27(09):  1612-1619 . 

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The conflict between conservation and development has emerged, due to the simultaneous increase of global protected areas (PAs) and local populations within and adjacent to the PAs. Assuming that PAs and their local communities are of an interactive system, the relationships between them were analyzed from two aspects, i.e., the influence of PAs upon the economic development, life quality, and cultural education of local communities, and that of local communities upon the biodiversity of PAs. Based on these analyses, three typical patterns on the relationships between PAs and local communities, i.e., harmonious development, unbalanced development (including community-damaged type and protected area- damaged type), and conflict and competition, were put forward, and the critical behavioral characteristics of these patterns in terms of employment opportunity, intensity of wildlife destruction and compensation, restrictions on resources utilization, tourism, community participation, breeding and grazing, collection of non-timber forest products, hunting, agricultural activities, and traditional conservation were distinguished, which could offer some information for the orientation of community management in PAs, and benefit the harmonious development between PAs and local communities.

Evolution of material metabolism in ecological-economic system of rapid industrialization county: A case study of Tongzhou City.

YU Shu-tong;HUANG Xian-jin;TAN Dan

2008, 27(09):  1620-1624 . 

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Tongzhou City experienced a process of rapid industrialization from 1996 to 2005, and the pressure on its resources and environment was getting higher. By using the method of material metabolism analysis within a system at regional scale, the evolution of natural environment load in Tongzhou City was analyzed. The results showed that in the city, the growth rates of the outputs of solid wastes, waste water, and exhausts emission were higher than those of the inputs of solid materials, fresh water, and fossil fuels, and the fixed substances accumulated quickly. The efficiency of material metabolism in Tongzhou City improved constantly, and the material metabolism rate and environmental press kept increasing. With the decreasing material and worsening environment, it was quite important to improve the efficiency of material metabolism for sustainable development sake. Under the background of rapid industrialization, we should build a reasonable industrial structure system, enhance the level of circular use of materials, set up management system of material flow, and take some other measures to increase the efficiency of material metabolism and reduce its frangibility at county scale.

Valuation of lake wetland ecosystem services of Yinchuan City.

SHAO Ning-ping;LIU Xiao-peng;QU Xiao-yi

2008, 27(09):  1625-1630 . 

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Yinchuan City is a typical oasis area in arid and semi-arid region of Northwest China, and its lake wetland is a kind of most characteristic and significant ecological resources. By the methods of market price, shadow price, substitute expense, expenditure, carbon tax, outcome reference, and shadow engineering, etc., the lake wetland ecosystem services of the city were evaluated. The results showed that this ecosystem provided a total of 130 288×10⁴ yuan services per year, among which, the service of material production was the largest (54 765×10⁴ yuan), followed by that of climatic regulation (25 851×10⁴ yuan), biological diversity (20 000×10⁴ yuan), recreation (9 661×10⁴ yuan), teaching and scientific research (7 460×10⁴ yuan), water conservation and flood and drought control (5 360×10⁴ yuan), habitat (5 000×10⁴ yuan), water supply (1 889×10⁴ yuan), and water purification and environmental landscaping (302×10⁴ yuan). Therefore, in the economic development and urban expansion of Yinchuan City, a scientific utilization and protection of its wetland resources should be taken, based on the consideration of whole ecosystem.

Double principal coorclinate analysis of herbaceous vegetation in wetlands of the Yellow River Delta, China.

XIONG Xiong;HE Qiang;CUI Bao-shan

2008, 27(09):  1631-1638 . 

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The herbaceous vegetation in wetlands of the Yellow River Delta, China was classified into 7 community types by TWINSPAN. Double principal coordinate analysis (DPCoA) was then applied for the ordination of the communities. The results from DPCoA ordination indicated that in species composition, Ass. Phragmites australis+ Suaeda salsa was a transitional type of Ass. Phragmites australis and Ass.Suaeda salsa+Phragmites australis, Ass. Suaeda salsa, Ass. Suaeda salsa+Limonium sinense+Suaeda glauca, and Ass. Limonium sinense, while Ass. Phragmites australis+Myriophyllum spicatum showed a great difference from others. The distribution of different community types was significantly correlated with soil salinity and soil pH, but not significantly correlated with soil total phosphorus, total nitrogen, and organic matter. Compared with principal component analysis (PCA) and detrended correspondence analysis (DCA), DPCoA may keep more accumulative information from the original data. It congregated the communities in the ordination chart which had fewer differences in their species composition and species taxonomy, but dispersed the communities which had greater differences in their species composition and species taxonomy. Therefore, DPCoA may be more efficient in investigating the structural relationships between different commnnty types and their relationships to environmental variables.