Table of Content

10 December 2005, Volume 24 Issue 12

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Effects of temperature,pH and drought stresses on ectomycorrhizal fungi growth in a Pinus sylvestris varmongolica plantation on sandy land

ZHU Jiaojun, XU Meiling, KANG Hongzhang, XU Hui, YAN Junjie

2005, (12):  1375-1379. 

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In this paper,ectomycorrhizal fungi(ECM fungi)Boletus sp.(BL),Lactarius sp.(LC) and Macrolepiota procera(MP) were collected from the sandy land Pinus sylvestris var. mongolica plantation in southeastern Keerqin in 2003 and 2004,and the growth of their pure culture was studied under simulated temperature,pH and drought stresses.The results showed that within the range of pH 3～7,the growth of the three test fungi was significantly different(P<0.05),with the optimum pH value being 5 for BL,6 for MP,and 7 for LC.The fungi could not grow at <5 ℃ or >37 ℃,and the optimum temperature was 25 ℃,25～28 ℃ and 25～30 ℃ for BL,MP and LC,respectively.The fungi could not grow when the PEG concentration was 30%((-1.53) MPa),but tended to increase when the PEG concentration was 10%(-0.20MPa).For LC,its growth was not influenced till the PEG concentration was 25%(-1.35MPa).With the real conditions considered,it could be deduced that the soil pH of the sandy land might fit the three test fungi,while the temperature and drought stresses during the growth season of P.sylvestris var.mongolica plantation might affect the growth and development of the fungi.Therefore,the decrease of ECM fungi should be one of the causes inducing the decline of P.sylvestris var.mongolica plantations on sandy land.

Carbon storage of alpine tundra ecosystem in Changbai Mountains

WEI Jing, DENG Hongbing, WU Gang

2005, (12):  1380-1383. 

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Carbon cycling in the alpine tundra of Changbai Mountains plays a unique role in the climate change of this region.In 2003,a field study was conducted to investigate the carbon distribution and storage in the plant,litter and soil of alpine tundra ecosystems at the elevations from 1950 to 2650 m.Four sampling plots were set up along the elevation transect,with an interval of 100 m.The plot size was 0.2?0.2 m,and all the plants in the plot were harvested.Soil bulk density was determined by the cutting-ring method at the depths of 5 cm and 15 cm.The results showed that the carbon storage of vegetation communities was typical alpine tundra(TT) > stony alpine tundra(ST) > meadow alpine tundra(MT) > swamp alpine tundra(WT) > rock sea alpine tundra(RT).The biomass of litter was 0.991 kg穐m^-2穣r^-1 in average,which was decreased in order of TT>ST>MT>RT>WT.The net storage of organic carbon was 3.6471?10⁵ t in the plant-soil system of Changbai Mountains,and the carbon storage of vegetation,litter and soil pool was(3.3457?10⁴t),(1.5053?10⁴ t) and(3.1620?10⁵ t),respectively.Plant stored(1.7251?10⁴t) carbon each year,and(1.5043?10⁴ t) of them entered into soil through litter-fall.The annual soil respiration rate was(1.4105?10⁴ t)穣r^-1.After vegetation succession stabilized,the average carbon storage was 3146 t穣r^-1.The alpine tundra of Changbai Mountains was the sink of CO₂.

Soil amorphous iron leaching and its relation with phosphorus leaching

WANG Daohan, SUN Tieheng, HE Na, DU Liyu, LIANG Chenghua

2005, (12):  1384-1387. 

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Soil amorphous iron is a medium of phosphorous fixation.With washing experiment,this paper studied the characteristics of soil amorphous iron leaching in paddy soils and its relation with phosphorus leaching.The results showed that adding citric acid and glucose had a significant effect on the leaching of soil amorphous and complex iron.A significant interaction was observed between soil moisture and temperature on the leaching of soil amorphous and complex iron.There was a close correlation between the leaching of soil amorphous iron and phosphorus.

Effects of alfalfa nectar amount and visiting bees number on alfalfa seed yield

HE Chenggang, BI Yufen, JIANG Hua, ZHOU He

2005, (12):  1388-1391. 

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This paper studied calyx diameter,nectar amount,the number of visiting bees and seed yield of ten alfalfa varieties.The results showed that there were significant correlations between nectar amount per m² and the number of visiting bees,the number of visiting bees and seed yield,as well as calyx diameter and nectar amount per m²,with the r value 0.87,0.93 and 0.99 respectively.Sitel and Derby varieties in Lanzhou area could produce seeds with high yield and good quality.

Monitoring of vegetation degradation in typical grassland with grassland health index

ZHANG Jian, LI Guicai, LIU Xianhua, HAN Xingguo

2005, (12):  1392-1396. 

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We established a regression model between Grassland Health Index(GHI) and visible/infrared and applied GHI in TM.Compared with NDVI image on the TM data,GHI reflects effectively the human disturbance on grassland.Moreover,GHI image could illustrate vegetation pattern,especially patch structure,better than other indices.Applying GHI to the historical TM data of this region,the vegetation cover change and change mode of grazing were discussed.

Leaf morphological characters of 22 compositae herbaceous species in Horqin sandy land

LI Xiaolan, LI Xuehua, JIANG Deming, LIU Zhimin, WANG Hongmei, JI Lanzhu

2005, (12):  1397-1401. 

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The study on the leaf traits of 22 compositae herbaceous species in Horqin sandy land indicated that there was a positive correlation between leaf volume and leaf thickness(r=0.782),while the correlations between leaf thickness and leaf tissue density,specific leaf area and leaf tissue density,and leaf volume and leaf tissue density were negative,with r values being-0.767,-0.559 and-0.505,respectively.No significant correlations were observed among other leaf traits.Based on the categorical or binary data,these 22 species were divided into 3 groups by cluster analysis.One-way ANOVA analysis suggested that there was a markedly significant difference among the groups in their leaf thickness,volume,weight ratio,and tissue density.

Effects of nitrogen fertilization on matter translocation of winter wheat cultivars at their grain-filling stage in sub-humid farmland ecosystem

FAN Yaning, LI Shiqing, WU Weimo, SHAO Mingan

2005, (12):  1402-1408. 

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A field experiment was carried out on the south Loess Plateau with an annual precipitation of 632 mm to study the effects of nitrogen fertilization on the matter translocation of winter wheat cultivars NR9405,9430,Yanshi No.9,Xiaoyan No.6,Shan 229,Xinong 2208,Aifeng No.3 and Sang 188 at their grain-filling stage.The results showed that there was no significant difference among different winter wheat cultivars in the dry matter production of green leaf,spike and stem at anthesis stage,and of leaf,hull and rachis at maturing stage,while a significant difference was observed in the dry matter production of old leaf and stem at anthesis stage,and of stem and grain at maturing stage.Nitrogen fertilization could significantly increase the dry matter production at anthesis and maturing stages.Among the test winter wheat cultivars,NR9405 had the highest dry matter translocation(DMT),dry matter translocation efficiency(DMTE),and dry matter translocation proportion for grain(DMTP),but Yanshi No.9 had the lowest ones.The DMT,DMTE and DMTP had a significant correlation with winter wheat cultivar and nitrogen fertilization.

Biomass production of different managed meadows in Tibetan Region of Northwest Yunnan Province

LIU Lingling, WU Zhaolu, LI Qing, XU Ning

2005, (12):  1409-1412. 

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In this paper,the plant species diversity and biomass production of different managed meadows in the Tibetan Region of Northwest Yunnan Province were investigated by plot methods.The results showed that in cultivated grassland,forage grassland and grazing pasture,the number of plant species was 49,24 and 12,aboveground biomass was 169.2?69.5,228.0?48.3 and 100.2?35.6 g穖^-2,underground biomass was 767.7?264.2,1593.5?553.0 and 2593.6?894.3 g穖^-2,and the ratio of aboveground biomass to belowground biomass was 1:4.5,1:7.0,and 1:25.9,respectively,suggesting that grazing pasture was characterized by less plant species and more underground biomass production,while forage grassland was beneficial to the maintain of high species diversity and high and stable biomass production,being worthy for promoting the grassland restoration in the studied area.

Occurrence characteristics of turf weeds under different management levels in temperate semi-arid region

WANG Yanrong, ZHAO Liqing

2005, (12):  1413-1417. 

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In this paper,an investigation was made on the species composition of turf weeds under three management levels in Hohhot during 2000～2002.The results showed that there were 80 species in total,with 67,37 and 36 species under lower,medium and higher management levels,respectively.Compositae,Legumiosae and Gramine were the dominant families,and the biological spectrum of weed communities were differed with turfs.Based on the index of harm degree,the turf weeds could be classified into five degrees,i.e.,extreme,heavy,medium,light and weak.Under lower,medium and higher management levels,the extremely and heavily harm turf weed species occupied 11.95%,21.63% and 22.22%,respectively.The extremely harm weed species included Viola prionantha,Digitaria ischaemum and Leymus secalinus,Viola prionantha and Geranium sibiricum,Potentilla anserine,L.secalinus and Inula britanica,respectively in the three management levels.V.prionantha,L.secalinus were the dominant species in spring and autumn,and D.ischaemum in summer.G.sibiricum was the dominant species in whole season.

Dynamic change and its prediction of ecological footprint in ecotone of Yunnan Province:A case study of Lijiang Naxi Autonomous County

JIANG Yiyi, WANG Yanglin, ZHANG Yuan

2005, (12):  1418-1424. 

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Prediction research is one of the important issues in ecological footprint(EF) study,which could overcome the static limitation of EF calculation through simulating the changing trend of EF,and have practical meaning in predicting and making strategic decision on regional sustainable development.In this study,the concept of EF and its calculation method were introduced to quantitatively assess the sustainability of Lijiang Naxi Autonomous County,northwest Yunnan Province,from 1949 to 2001.Based on the TM images in 1988,1996 and 2001,the calculation of the ecological capacity(EC) showed that on the whole,the EF of this County had an ascending trend from 1949 to 2001,being increased from 0.2938 hm²穋apita^-1 in 1949 to 1.351 8 hm²穋apita^-1 in 2001,and thus,the pressure on local ecological environment becoming more and more serious because of the rising consumption level.In test period,this County was under 'ecological surplus',and there was a harmonious relationship between social-economic development and environment.The prediction results indicated that the EF would be higher than the EC in 2015,if the present development rate could be kept,which meant that Lijiang Naxi Autonomous County would use more biologically productive land within its borders,and highly depend upon external ecosystems to provide its needed food,material,energy resource and waste digestion.Such a development state should be unsustainable.

Diurnal variation of carbon dioxide flux on water-air interface of Meiliang Bay,Taihu Lake in wintertime

LI Xianghua, HU Weiping, YANG Longyuan, ZHANG Fabing, HU Zhixin

2005, (12):  1425-1429. 

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Employing statistic box method,this paper monitored 72 h continuously the diurnal variation of carbon dioxide flux on the water-air interface of Meiliang Bay,Taihu Lake in wintertime.The results showed that in clear and breezy days,water was the sink of atmospheric carbon dioxide at daytime,and its carbon dioxide flux was about zero at night,with the mean values of carbon dioxide flux being -3.01 and-0.02 mg穖^-2穐^-1,respectively.But,in cloudy days and after a durative gale,water was a strong source of atmospheric carbon dioxide,with the maximum value 76.53 mg穖^-2穐^-1.It could be concluded that wind speed had a significant effect on CO₂ flux in wintertime.

Plant species diversity in hilly regions of Fangshan Mountain

WANG Yinggang, ZHANG Qiuhua, LI Yun, ZHANG Feng

2005, (12):  1430-1433. 

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Based on the investigation data of 27 sampling plots,the plant species diversity in the hilly regions of Fangshan Mountain was analyzed from the aspects of component similarity,and species richness in various layers.The results showed that the species richness was lower in tree layer,but higher in shrub and grass layers.The species diversity was decreased with increasing altitude,but was higher on northern than on southern slope at the same altitude.Human activity had a significant effect on the plant species diversity.

Comparative study on stem sap flow of non-and ring-porous tree species

SUN Huizhen, LI Yiping, WANG Cui, ZHOU Xiaofeng

2005, (12):  1434-1439. 

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By the method of thermal dissipation,this paper studied the dynamic characteristics of the stem sap flow of Fraxinus mandshurica and Pinus sylvestris var.mongolica,the two major classes of wood anatomy,non-porous(coniferous) and ring-porous,at the Forest Ecosystem Research Station of Maoershan Mountain during growth season.Air temperature and relative humidity,soil moisture,and soil temperature were also measured.The results showed that on sunny days,the diurnal variation of sap flow density presented mono-peak pattern,mostly occurred from 9 AM to 14 PM.The maximum sap flow density was three times greater in F.mandshurica than in P.sylvestris var.mongolica.The ratio of sap flow quantity at nighttime to those in whole day was less than 20%,except in later autumn,indicating the effect of root pressure.After all leaves fallen till mid-October,there still existed sap flow.The seasonal average sap flow density was 48% higher in F.mandshurica than in P.sylvestris var.mongolica.Effective photosynthetic radiation and deficient vapor pressure were the dominant environmental variables affecting the diurnal variation of sap flow density on sunny days.

Comparison of ecotoxic effect of selenium on seed germination of wheat and paddy rice

SHAO Zhihui, LIN Kuangfei, XU Xiaoqing, ZHENG Li, XIANG Yaling

2005, (12):  1440-1443. 

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Ecotoxic effects of selenium on the seed germination and seedling growth of wheat(Triticum aestivum L.) and rice(Oryza sativa L.) were studied by solution culture experiment.The results showed that low concentration of Se(under 0.5 mg·L^-1) could promote the seed germination of wheat and its seedling growth,while high concentration of Se(above 5 mg·L^-1) reduced the germination rate,the seedling growth and vigor and α-amylase activity markedly.The inhibition rates of seed germination indices of wheat were stronger than those of rice,among which the root elongation was the most sensitive.There was significantly positive correlation between the inhibition rate of seed germination and the concentration of Se in solution.The inhibition rate of root elongation of wheat seeds could be used as a biomarker to assess the ecological risk of selenium pollution.

Accumulation and distribution of copper granules in shrimp Macrobrachium nipponense

LU Xingjia, XI Yilong, LIU Guiyun

2005, (12):  1444-1448. 

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By the methods of histochemistry,transmission electron microscope(TEM) and atomic absorption spectrophotometer(AAS) analysis,this paper studied the accumulation and distribution of copper granules in the major organs of shrimp Macrobrachium nipponense exposed to 0.08 mg稬^-1 Cu²⁺ for 10 days.The results showed that there were large amounts of high electronic dense copper granules in the hepatopancreas of M.nipponense,which primarily deposited in tubules and R cells,and then excreted to haemocyte space.Under ultrastructure,the copper granules were mainly deposited in the lysosome of hepatopancreas cells,and a less amount of them was absorbed in smooth-surfaced endoplasmic reticulum.The copper granules were excreted to the lumen by apocrine secretion.There were copper granules in midgut cells,and vacuolus occurred in the cytoplasm of cells.The cristae in mitochondria were disintegrated partially,and copper granules were absorbed into mitochondria.A little amount of copper granules was deposited in the lysosome of antennal gland cells,and endoplasmic reticulum was curved in the cells.The highest concentration of copper(546.39 mg穔g^-1) was found in hepatopancreas by AAS,suggesting that hepatopancreas might play an important role in storing copper.

Vegetation restoration after emergent water conveyance to lower reach of Tarim River

LI Xia, HOU Ping, DONG Xinguang, ZHU Xiaohu

2005, (12):  1449-1453. 

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Based on the vegetation survey on different cross section at different distance from Tarim River after the fourth emergent water conveyance to the lower reach of the River,this paper analyzed the relationships between the underground water depth on the both sides of the lower reach of Tarim River and the ecological restoration of vegetation.The results showed that after the fourth emergent water conveyance,the regeneration of Populus euphratica occurred at the places about 150 m away from the river,with a groundwater depth <4 m.A quantitative relationship was found between vegetation recovery,species composition and growth status,distance from the river,and underground water depth,which supplied a scientific basis for determining the ecological restoration range and the adjustment of water conveyance scheme after emergent water conveyance to the lower reach of Tarim river.

Spatial and temporal distribution of water hyacinth population in Shanghai and its control methods

JIN Liang, WANG Xiaojuan, GAO Lei, DONG Huiqin, LI Bo

2005, (12):  1454-1458. 

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Water hyacinth(Eichhornia crassipes) is a notorious invasive species in the water bodies of Shanghai,the biggest city of China.The study in Shanghai and its administrative districts from July 2002 to December 2003 showed that the distribution of water hyacinth population was disproportional,the most in Qingpu,Jinshan,Songjiang and Jiading,medium in Fengxian,Nanhui and Baoshan,and least in Pudong,Chongming and urban districts.The population dynamics of E.crassipes was significantly correlated with water quality and with other hydrophytes lived together,and thus,the effective control methods should be integrative,i.e.,under the coordination with Jiangsu and Zhejiang Provinces,control other hydrophytes,decrease river pollutants,and salvage the clones of water hyacinth from December to next June.

Effects of allelochemicals on seed germination

YANG Qihe, YE Wanhui, LIAO Fulin, YIN Xiaojuan

2005, (12):  1459-1465. 

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All kinds of allelochemicals can affect seed germination through affecting seed cell membrane permeability,cell division and differentiation,respiration,protein synthesis,gene expression,and hormone synthesis and equilibrium.The allelopathic effects on seed germination are related to the types and concentrations of alleochemicals,species of recipient plants,and environmental conditions.In this paper,the definitions of plant allelopathy and allelochemicals,and the releasing modes and types of allelochemicals were introduced,with the focus on the action mechanisms of allelochemicals on seed germination,their affecting factors,and ecological significances.

Research progress on environmental and ecological functions of earthworm

HUANG Chulong, ZHANG Xueping

2005, (12):  1466-1470. 

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Earthworm plays an important role in promoting the activities of soil microbes and soil fauna,accelerating the fragmentation,digestion and decomposition of litters,improving soil fertility,and indicating environmental conditions.At present,its study in China is focused on polluted ecosystem rather than natural wetland and forest ecosystem.In foreign countries,the research items in 1970s were the same as our present studies,but in 1980s,the focus was on the different scales of physiological ecology,population ecology,community ecology,and ecosystem ecology.Since 1990s,the study has been widened to molecular ecology and landscape ecology.Henceforth,besides the studies mentioned before,more attention should be paid to improve the research precision by applying high-technological research methods,practicability by integrating the studies in laboratory and field,and comparing the environmental adaptability of special species of earthworms and their inoculations.

Effects of man-made ditch on eco-environment:A research review

XI Min, LU Xianguo, LIU Hongyu

2005, (12):  1471-1476. 

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Man-made ditch is the artificial channel excavated for drainage and irrigation.As the corridor of drained and irrigated water,it can improve soil structure,promote crop growth,and thus,improve crop output.The existence of man-made ditch also has great effects on the environment around,among which,hydrological effect is the most available and acceptable one.Observations during and after rain events showed that man-made ditch contributes effectively to the runoff at the outlet.Some of the ditches can collect water and transfer it towards river,and the others can collect water and make it slow down.In this paper,the effects of man-made ditch on hydrology,element geochemistry,organisms and their habitats,and whole eco-environment were summarized,and suggestions on its further study were put forward,with the aim of exerting the effects of man-made ditch to benefit eco-environment.

Research on soil animal community ecology in China

ZHU Yongheng, ZHAO Chunyu, WANG Zong-ying, PU Lijie

2005, (12):  1477-1481. 

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Features of soil animal community ecology researches in China were summarized in this paper,including that the research areas mainly distributed in eastern China,extensive ecological systems were investigated from different aspects,and rapid development in application researches.Research developments were summarized from the view of ecology,i.e.relationships between soil animal community and environment,composition and diversity,structure,function,succession and soil animal community in disturbed ecosystems.Several key fields in soil animal community ecology research in the future were put forward.

Status and prospects of crop straw comprehensive utilization in hilly red soil region

ZHU Qihong, HUANG Daoyou, LIU Shoulong, ZHANG Wenju, SU Yirong, WU Jingshui

2005, (12):  1482-1486. 

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In this paper,the annual production of straw in China hilly red soil region from 1993 to 2003 was calculated,according to the economic indices of crop straw and crop yield.The averaged annual straw production was 33.5?10¹⁰ kg穣r^-1,accounted for 52.1% of total crop straw production in China.In this region,rice straw accounted for 53.5% of total crop straw,which was 21.4% higher than the average countrywide value.The percentages of other kinds of crop straw in this region were also different with those of the whole country.The changes of rice and other grain crops straw production among years were basically the same to that of all the crop straw in this region,i.e.,an increasing trend was found from 1993 to 1997,but declined then.The changes of economic crops straw production varied with different kinds of crops.The utilization ratios of straw incorporation and industrial use in this region were 32.0% and 6.6%,respectively,which were higher than the average countrywide value,while those for fuel and forage were 22.0% and 14.1%,respectively,which were lower than the average countrywide value.The average percentage of wasted straw was 25.3%,and increased from 20.6% to 29.6% between 1993 and 2003,suggesting that a big amount of crop straw in this region was thrown away or burned,which was obviously a waste of restricted agricultural organic resource.Countermeasures were put forward in this paper to adjust the crop straw utilization framework status,and to enhance the utilization efficiency of crop straw.

Research advance in landscape pattern optimization

HAN Wenquan, CHANG Yu, HU Yuanman, LI Xiuzhen, BU Rencang

2005, (12):  1487-1492. 

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The theories and technologies for optimizing landscape pattern are the key issues in landscape ecology research,and increasing emphasis is on the issues especially as the turther studing of the relationships among landscape pattern,landscape function and landscape process.Landscape pattern optimization aims to build a kind of optimized landscape which could make landscape eco-efficiency maximized and ecological safety ensured,based on the understanding of the relationships among landscape pattern,landscape function and landscape process,and the proposing of optimal target and criteria.The researches mainly include the theories,technologies,and targets of landscape optimization and landscape management.This paper summarized the research advance on landscape pattern optimization at home and abroad,and some comments were put forward.Through analyzing some case studies,it was pointed out that landscape optimization research should integrate multiple methods,make quantitative study,and establish related evaluation standards.

Impacts of disturbances on alpine timberline reformation

FANG Jinqi, WU Ning, LUO Peng, YI Shaoliang

2005, (12):  1493-1498. 

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With special ecological structures and functions,alpine timberline,a kind of ecotones highly sensitive to disturbances and environmental changes,has become one of the major concerns in global climate change studies.After reviewing the definitions of alpine timberline,this paper discussed the impacts of disturbances on the reformation of timberline from the aspects of its changes in elevation position,vegetation pattern,species composition,and physiological characteristics.It was suggested that the responses of alpine timberline species to disturbances could be basically summarized in two ways:(1) withdrawing: tree species are replaced by new species(usually herbaceous or bushes) after disturbance,and the tree species will withdraw(downward) or disappear;and(2) inbreaking: non-constructive species replace constructive(keystone) species or spread to surrounding area,especially upward along the altitude.The potential increase of timberline resulted from climate warming is compromised to some extend as a result of disturbances.Therefore,distinguishing various disturbances and their effects with climate change is crucial to understanding not only the reformation process of timberline,but also the causes of current vegetation formation in the areas as well.

Chemical forms of soil heavy metals and their environmental significance

HAN Chunmei, WANG Linshan, GONG Zongqiang, XU Huaxia

2005, (12):  1499-1502. 

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This paper introduced the chemical forms of soil heavy metals and their analytical methods,with the focus on the distribution and conversion of different form heavy metals and their affecting factors.The chemical forms of soil heavy metals are of significance for evaluating their mobility and bioavailability,and the possibility of soil remediation,while chemical form analysis could reflect the contributions of natural and human activities to the sources of soil heavy metals and their ecotoxicities.Soil heavy metals could have different toxicities and environmental behaviors due to their chemical form conversion.

Eco-environment in Three Gorges Reservoir area and countermeasures for its sustainable development

ZHOU Bin, DONG Jie, GE Zhaoshuai, TANG Jigang, YANG Dayuan

2005, (12):  1503-1506. 

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The study on the recent eco-environmental condition in the Three Gorges Reservoir area showed that the vulnerability of eco-environment,irrational exploitation of natural resources,and misgovernment and legal sense absence were the main causes of the deterioration of the eco-environment in this area.Some countermeasures,e.g.,restoring and rebuilding eco-environment,converting agricultural production modes,and reforming administration system,were proposed to ensure the sustainable development of this area.

Research advances in plant resistance mechanisms under lead stress

YANG Gang, WU Jun, TANG Ya

2005, (12):  1507-1512. 

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The paper reviewed the plant resistance mechanisms under lead stress from physiological and biochemical aspects,e.g.,cell division,permeability of plant membrane,photosynthesis,antioxidative enzymes system,etc.,and discussed the relationships of plant resistance with Pb²⁺ transportation across membranes,root exudates,metal cheaters,and Pb²⁺ distribution in plants.

Development of China green food industrialization: Its theory and practice

LI Xianjun, WU Wenliang, LI Zhifang

2005, (12):  1513-1519. 

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Based on the case study of the state green food production demonstration area in Ji County of Tianjin,and of the state leading enterprise,Caoyuanxingfa Group Company,this paper put forward a basic framework and theoretical foundation on the management of China green food industrialization.The basic framework was composed of agricultural production,processing enterprises,farmers,and marketing departments,among which,there existed a specific and mutual dependent economic and technical relationship.Under the guidance of the theories and principles of agricultural industrialization,sustainable development of agriculture,green economy,green marketing,market economy,and agricultural ecology etc.,such a framework was market-oriented,aiming at promoting economic benefits,and was under the formation of "market leads along leading enterprises,leading enterprises organize production bases,and production bases connect farmers" to optimize production factors and implement regional arrangement,professional production,integrative management,social service and company management,and to achieve the sustainable management of resources,the optimization of environment,and thus,the optimal benefits of social,economy and environment,which could be favorable to improve the multi-production and exportation of China agriculture.

Major effects of road construction on eco-environment

ZHENG Haifeng, GuAN Dongsheng

2005, (12):  1520-1524. 

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Road is an important type of global landscapes,and its length and density is increasing year after year.The quantity and quality of natural habitats are decreased and worsened by road infrastructures and road networks.The major ecological effects of road construction on eco-environment include habitat loss,eco-disturbance,barrier effects,corridor effects,and serious habitat fragmentation induced by road networks.Three countermeasures were put forward to mitigate the habitat fragmentation by road infrastructure.

Assessment of sustainable development level of social,economic and ecological complex system in poverty-stricken districts of Hunan Province

FU Shaochun, ZHANG Xinbin, ZHANH Canming, JIANG Lijuan, TAN Zhuming, YAO Min, SHI Dongying

2005, (12):  1525-1530. 

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This paper studied the sustainable development level of the social,economic and ecological complex system in the poverty-stricken districts of Hunan Province,aimed to alleviate the poverty,improve the ecological environment,and understand the development potential of these districts.The data of natural situation,ecology,economy and society were collected from 31 poverty-stricken counties,with the weight coefficients decided by principal component analysis and analytical hierarchy process.Combining multivariate analysis and weighted by standard index-integrated method,the comprehensive assessment and comparison of sustainable development level within and outside these districts were conducted from the aspects of natural resources,economy,environment and society.

Relationships between soil fertility and secondary succession of plant community in Jinyun Mountain

SONG Huixing, SU Zhixian, PENG Yuanying

2005, (12):  1531-1533. 

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In this paper,the variation characteristics of soil fertility at different succession stages of the plant communities in Jinyun Mountain,Chongqing City was evaluated,based on the soil physical,chemical and biological properties,and with the integrative evaluation index system.The values of integrated soil fertility index of shrub,coniferous forest,coniferous and broad-leaved mixed forest,evergreen broad-leaved forest were 0.0086,0.3407,0.5104 and 1,respectively,implying that soil fertility was improved with succession,and plant community played an important role in the development process of soil.The variation of soil fertility also affected the adaptability of species to environment and the competition among species.It was suggested that soil fertility was the important factor affecting plant succession course.

Composition and diversity of Acaroid mite community in house ecosystem of Huainan area

LI Chaopin, WANG Huiyong, JIANG Jiajia, HE Ji

2005, (12):  1534-1536. 

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To investigate the composition and diversity of Acaroid mite community in the house ecosystem of Huainan area,A.mite in four different habitats were collected,isolated,and identified.The results showed that the positive rate of acaroid mites was 44.9%,which varied in different breeding places,i.e.,32.5% in bed dust,52% in floor dust,32.5% in clothing dust,and 26% in furniture dust.14 species were detected,belonging to 11 genera and 5 families.Diversity analysis suggested that the species richness index R_margalef for the four habitats ranged from 0.400 to 1.170,while the species diversity index(Shannon-Wiener index) ranged from 1.574 to 2.480,and Pielou index ranged from 0.967 to 0.978.Temperature,humidity and food habit were the major limiting factors determining the species composition and diversity of acaroid mite community in house ecosystem.Human disturbance also affected the species composition of acaroid mite community.

Sylvicultural technique on three types of soil in hilly-gully regions of Loess Plateau

CAO Shixiong, CHEN Li, GAO Wangsheng

2005, (12):  1537-1542,1552. 

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In the hilly-gully regions of Loess Plateau,the erosion-incision induced by long-term water and soil loss resulted in the disappearance of topsoil and the bareness of three types of soil(loess parent material,red-clay,and mantle rocky soil),which increased the difficulty of afforestation.In this paper,the afforestation principle "selecting suitable tree species for suitable soils" and the drought-resistance planting technique of "cave padded plastic film" were put forward,which could broaden the soil types to suit for planting trees.This planting technique was examined at the Xiaobangou basin of Yan'an city from 1997 to 2001,and the results showed that this technique could promote root growth in topsoil layer,keep soil water for 4 months,and significantly improve the survival rate and growth volume of all types of trees.The afforestation effects were better on the three types of soil in Loess Plateau,if the new planting technique was adopted.The red clay and mantle rock soil distributed on the both sides of gully with rich ground water were better for shallow-root trees to grow,and could obtain better effects if planting in scientific mixed planting.

Application tryout of chlorophyll meter SPAD-502 in forestry

JIANG Lifen, SHI Fuchen, WANG Huatian, ZU Yuangang

2005, (12):  1543-1548. 

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Chlorophyll is the pigment for plant photosynthesis,and its traditional measuring method is spectrophotometry.In this research,portable chlorophyll meter SPAD-502 was used to measure the seasonal changes of the greenness(SPAD) of 4 broad-leaved tree species under larch(Larix gmelinii) plantations,with the correlation between SPAD value and chlorophyll content measured by spectrophotometry investigated.The results showed that there was a significant correlation between SPAD value and chlorophyll content,indicating that SPAD value could well reflect the changes of chlorophyll content in tree foliage,and it was feasible to measure the chlorophyll content by chlorophyll meter instead of spectrophotometry.Chlorophyll meter SPAD-502 should be used broadly in forestry research because of its convenience to carry,simple and rapid measurement,and no damage to leaves.

Single sine phonological model of thermal accumulation and its application

LU Zhaozhi, TIAN Jianhua, SHEN Zuorui, TIAN Changyan, WANG Tao

2005, (12):  1549-1552. 

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The paper details the calculation method of single sine phonological model(SSPM) in insect phenology,in which the daily temperature is curved by sine function.Accumulations and daily degree-days are acquired by integral equation methods.Two parameters,low temperature threshold and upper temperature threshold,and two input values,daily minimum and maximum temperature are applied in degree-days calculation.There were six equations under combination of those parameters.Taking cotton bollworm(Helicoverpa armigera) for instance,the calculation and prediction process of SSPM are clarified in insect phenology.With the development of the Internet and automation weather station,SSPM have more prospective application in regional pest management.