Abstract:针对不同管理方式竹林坡地水土流失过程中携带养分流失的特征,于2008年和2009年在浙江省临安市和安吉县,分别选择用材竹林坡地和挖笋竹林坡地,建立径流小区(面积3m×1.5m,坡度20°),设计用材林不锄草、清鞭和施肥,笋林地除草清鞭每年1次和2年1次、每年施肥1次,共3种管理方式,采用人工模拟降雨的试验手段,设定6个降雨强度(0.53～1.90mm/min),定时采集径流泥沙样,测试径流中的总氮(TN)和总磷(TP)含量,研究不同管理方式下竹林地N和P的流失过程特征,分析流失差异的原因。结论如下:(1)在相同管理方式下,径流中TN和TP的流失量随雨强在增加,以雨强为1.01mm/min为界,小于该雨强时增加量很微弱,大于这一雨强时增加速率很快;(2)在相同雨强作用下,笋竹林地径流中TN的流失量是用材竹林地的3～7倍,但径流中TP的流失量却略小于用材竹林地的流失量;(3)泥沙中TP的流失量,笋竹林地是用材竹林地的数百倍;(4)在N和P随径流泥沙的流失过程中,产流前期浓度起主要作用,后期径流量和产沙量起决定作用。研究结果可为竹林地管理、笋用竹林地锄草、清鞭和施肥的科学合理安排提供参考依据。

Abstract:The article explored the influence of nitrogen fertilizer application with several times under different irrigation modes on nitrogen and phosphorus loss in paddy fields under field experiment condition.The results indicated that the runoff of total nitrogen and phosphorus was between 4.41~17.85 kg/hm2 and 0.28~0.44 kg/hm2 under different fertilizer treatments with traditional irrigation respectively.The loss percentage of nitrogen and phosphorus fertilizer was respectively about 3.2% and 0.17%.Compared to ...

Abstract:Effects of applying different nitrogen fertilizer or water and DCD on cucumber yield,quality and nitrate leaching loss in soil were studied in greenhouse.The results showed that there was no significant difference in cucumber yield of the conventional water and nitrogen management and optimize water and nitrogen management,with sidedressed N input in comparison with conventional water and nitrogen management.Nitrate content in cucumber in optimize water and nitrogen management was significantly lower than t...

Abstract:The effects of planting types(ridge planting and furrow planting) on runoff,sediment and surface soil structure stability were determined in vegetable field with polyethylene mulch and ridge-furrow system of contour terrace in the Dianchi lake's catchment.The results showed that there were no significants difference of bulk density,pores distribution and water stable macro-aggregates(>0.25 mm) content between furrow planting type(FP) and ridge planting type(RP) in 0-5 cm soil layer after vegetable harvestin...

Abstract:Soil columns experiment was used to investigate the effects of active carbon application on soil infiltration,evaporation characteristics and leaching loss of nutrients.There were six treatments with different active carbon's contents:0%(the control treatment),0.1%,0.3%,0.6%,0.9% and 1.2%.The results showed that:Along with the increase of active carbon application,the soil infiltration increased to a certain degree and then declined.After 100 minutes infiltration,the highest and lowest cumulative infiltrati...

Abstract:Based on the problems of serious soil and water loss on the sloping farmland in the gentle hilly region of the northern of song-nen plain,during the year of 2009 and 2010,the comprehensive technique model of combining engineering technology and farming technology was first used by natural rainfall to study,the runoff plots included five kinds of soil and water conservation technology modes of mole drain,the combination of mole drain and subsurface pipe,furrow damming,the combination of mole drain and furrow...

Abstract:Phosphorous and nitrogen losses characteristic in the runoffs in watersheds of Laoshan reservoir were studied based on runoff observations on four types of non-point pollution generating areas,i.e.forest land,orchard,cultivated land,and village.Synchronous monitoring of rainfall and water quality in the runoffs were performed during a rainy season in 2009.The results showed that the concentration of NH+4-N and dissolved total phosphorus in runoffs was much larger from village than those from other types,and...

Abstract:The distribution of soil physical properties and permeability with four restoration patterns were studied in Caopo river watershed,which located in Wenchuan county.The results showed:(1)Soil bulk density,total porosity,capillary porosity and noncapillary porosity,and other physical properties in the slope surface distribution showed significant differences,because of the ecological destruction caused by Wenchuan earthquake.(2)The water holding capacity of natural plants returned slope surface biggest had a ...

Abstract:The slope infiltration and run-off characteristics of artificial pine woodlands and bush-grass lands in Taihang mountainous region was studied by runoff plot experiments.The results showed that:The slope run-off was less and the infiltration was larger in two vegetation covers.The amount of run-off and infiltration were both increased with rainfall increasing.The amount of run-off and infiltration in pine forest plot was less than that in shrub and grass plot when the rainfall was small,but the run-off in p...

Abstract:Because of irrational structure and low benefits of windbreaks in northern Shanxi,the wind erosion quantity of the soil in severe section can reach as high as 120~135 m3/hm2.In order to provide a theoretical basis for design of windbreaks,based on an analysis of occurring rules of hazardous wind,characteristics of sandstorms and mechanical structure of topsoil in northern Shanxi,a research on key factors for design of windbreaks had been done by establishing mathematical models.The results are as following:...

Abstract:Simulated sand-fixing shrub is a new type of preventing wind and combating sand material which is made of high polymer materials mingled with antiaging agents in accordance with the simulation principle,its shape is as same as the shape of wild desert shrubs such as Artemisisa desertorum,Artemisia ordosica etc.having good effects in reducing wind and fixing sand.The different porosity of simulated sand-fixing shrubs were tested to their capacity of preventing wind and combating sand in the wind tunnel under...

Abstract:The method of wind erosion ring and pitfall tripping were used to observe the effect of strip width on the wind erosion modulus and verify the results received by field mobile wind tunnel.The wind erosion and wind-blown quantity were determined and the results showed that wind-blown quantity was decreased when the width was narrower than 6 m and increased with the increasing of strip width when the width was 6~10 m,and decreased when the width was wider than 10 m in the stubble of naked oat.The wind-blown q...

Abstract:Through experiments in standard runoff plots,this paper studied effects of vetiver hedgerow on bulk density,particle distribution and nutrient loss in the surface soil layer(0-20 cm) of different slope farmland in the purple soil area,Sichuan,China.The results showed that Vetiver hedgerow could reduce soil bulk density,but the effect was not significant.Under hedgerow's effect,small soil particles(silt,clay) obviously enriched in the bottom and middle of slope,and the quantity of small particles loss reduce...

Abstract:Understanding the applied effects of water retentive agents(WRA) on Salvia miltiorrhiza Bge(SMB) is helpful to use it reasonably in SMB field planting with resisting drought and saving water.The paper is to analyze the effects of different WRA application on the formation of SMB dry matter and the absorbability of nitrogen,phosphorus and potassium and their use efficiencies with a pot culture experiment.The results showed that WRA application had a positive effect on the accumulation and distribution of SMB...

Abstract:Field experiment were carried out on grain yield of summer maize to determine the effect of different proportions of water-base controlled-release coated urea of 60 d release duration combined with conventional urea as topdressing on nitrogen utilization,nitrogen agronomic efficiency,nitrogen partial productivity,nitrogen harvest index and nitrogen accumulation.Dynamic distribution of nitrate content in soil was also studied.The findings indicated that the treatment of controlled-release urea combined with ...

Abstract:为探讨黄河三角洲盐碱地不同道路防护林对土壤的改良效应,选取白蜡(Fraxinus chinensis)+毛白杨(Populus tomentosa Carr)混交林、旱柳(Salix matsudana Koidz)林、柽柳(Tamarix chinensis Lour)林、白蜡(Fraxinus chinensis)林4种盐碱地道路防护林类型,并以裸地为对照,对其土壤容重和孔隙度、pH值和含盐量、土壤养分及C、N、S含量特征进行对比研究。结果表明:①与裸地相比,不同道路防护林具有降低土壤容重,增加土壤孔隙度的显著效应,并且表现出一定的压碱抑盐效应。随着林分类型的不同表现出一定的差异,其中混交林地土壤通气、透水性及压碱抑盐效果好于柽柳灌木纯林的,而旱柳林和白蜡林地的则较差。②不同道路防护林土壤有机质含量及速效性养分含量均有提高,其中土壤有机质含量依次为混交林>柽柳林>白蜡林>旱柳林,分别比裸地的增加49.5%,38.8%,18.9%,5.7%。③不同道路防护林下的C、N、S元素含量差别较大,元素含量表现为:C>S>N。N含量表现为混交林>柽柳林>白蜡林>旱柳林,分别是裸地的2.8,2.2,1.5,1.1倍。C...

Abstract:以黄土母质生土为供试土壤,以不同类型豆科植物为生物材料,对生物改土效应进行研究。结果表明:①草木樨、苜蓿根际土壤容重在1.00～1.35g/cm3之间,是最适宜的土壤容重范围;黑豆、大豆对0.25～3mm之间团粒具有较强的作用;种植草木樨、苜蓿、黑豆、大豆后,土壤>0.5mm水稳性团聚体的含量均在90%以上。草木樨、苜蓿、黑豆和大豆对土壤物理性质具有良好的改良作用。②草木樨、苜蓿、小冠花在短时期内对土壤氮素具有较强的补给作用;豆科牧草在生土地上生长两季后,对土壤0-60cm土层氮素具有明显的表聚效应;土壤表层有机质含量以小冠花最高;0-20cm土壤表层速效P的含量均极显著高于其他层次的;红三叶和小冠花土壤速效K含量高于草木樨和苜蓿的。种植红三叶和小冠花对土壤表层肥田效果比草木樨和苜蓿占优势。③一年生高产植物大豆随生长进程的前、中、后期土壤N素表现了高-低-高的积累-消耗-再积累的过程,土壤N素循环较大。研究为生物改土、有机沃土提供了理论参考。

Abstract:The characteristics of nutrients and conditions of abundance or scarcity were studied,and integrated evaluation were conducted with respect to soil planted with tobacco in Wulong county.The 312 samples were taked by GPS locating and analysed by laboratory test.The results showed that most samples are of moderate content of organic matter,pH are of weak acidity,higher content of total N,moderate content of available N,77.56% of samples are of P scarcity,approximately 60% of soils are suitable for tobacco gro...

Abstract:The sediment yield and infiltration are affected by rainfall intensity based on simulated rainfalls.The results showed that the sediment delivery rate changed smoothly under rainfall intensity of 60 mm/h and the sediment delivery rate fluctuated due to rill during rainfall,the appearance of rill need more time of 5~20 minutes under rainfall intensity of 90 mm/h than that under rainfall intensity of 120 mm/h,the total sediment yield was increased obviously with the addition of rainfall intensity,the increase...

Abstract:The consequences of global climate change are drought frequent and rainfall increased,researching the effects of rainfall events on soil microbial biomass and soil respiration is important to understand of ecosystem C and N dynamics in terrestrial ecosystems.Based on a continuous observation before and after the rain in Beijing,changes in contents of soil microbial biomass and soil respiration under different land use conditions were determined.Furthermore,different responses of soil microbial biomass and s...

Abstract:以黑土为供试土壤,采用化学试剂模拟根系分泌物进行室内培养试验,研究低分子量根系分泌物及主要组分对土壤微生物活性及团聚体稳定性的影响。结果显示,与对照相比,低分子量根系分泌物及主要组分短期内均显著提高了土壤微生物的活性,促进了>250μm大团聚体,尤其是>2 000μm团聚体的形成,显著增强了土壤团聚体的稳定性。低分子量根系分泌物中葡萄糖组分有利于土壤中细菌的生长,从而在细菌活动的驱动下,促进了微团聚体的形成;苹果酸和谷氨酸组分则有利于真菌的生长和繁殖,在真菌菌丝网络的缠绕和粘结作用下,促使微团聚体进一步胶结形成大团聚体。因此,低分子量根系分泌物中各主要组分共同参与并影响土壤的团聚化过程,改善根际微区土壤的结构,以利于植物根系的生长。

Abstract:During soil erosion process,soil aggregate transport reflects the broken degree of soil aggregate and runoff transport capacity,which directly affects soil erosion degree.A laboratory rainfall simulator study was conducted to determine characteristics of sediment yield and soil aggregate transport of different size fractions(>5 mm,2~5 mm,1~2 mm,0.5~1 mm,0.25~0.5 mm and <0.25 mm) under different soil surface conditions on typical black soil in the northeast China.Three soil surface conditions were designed: ...

Abstract:This article studied the influence of long-term localized fertilization on distribution of soil aggregates and phosphorus forms in fluvo-aquic soil.The results showed that:(1)The main weight body of fluvo-aquic soil aggregate was 0.25~5 mm(60.72%~77.99%),followed by >5 mm,the lowest was <0.25 mm(7.09%~13.68%).Soil aggregate(0.25~5 mm)weight proportion of inorganic fertilizer was 60.72%,it was significantly lower than other treatments(71.5%~77.99%),whereas >5 mm aggregate weight proportion was significantly ...

Abstract:Soil particulate organic nitrogen as the instable part of soil organic nitrogen,playing an important role in the nitrogen balance,and is of great significance in the growth of plant and the increase of crop yield.In this paper four tillage treatments including conventional tillage with rice only system(DP),conventional tillage with rotation of rice and rape system(SH),no-till and ridge culture with rotation of rice and rape system(LM),and tillage and ridge culture with rotation of rice and rape system(LF) w...

Abstract:通过8年定位试验,研究不同施肥制度下褐土及其微团聚体内酸解性氮变化规律,从各级微团聚体全氮和酸解性氮储量角度探讨不同施肥制度下土壤氮素肥力的变化实质。结果表明,不施肥处理主要是由于10～50μm粒级全氮和酸解性氮储量降低而造成土壤氮素肥力下降;单施常量NPK化肥处理有同样趋势;增量NPK化肥处理主要通过提高<10μm粒级全氮和酸解性氮储量使土壤全氮和酸解性氮含量不下降;有机肥(物)料配施常量NPK化肥处理则主要通过增加大粒级特别是10～50μm粒级全氮和酸解性氮储量、降低<10μm粒级酸不溶性氮储量而使土壤氮素肥力水平得到提高,猪厩肥效果好于玉米秸和麦秸直接还田。采用有机肥(物)料配施常量NPK化肥是改善土壤氮素肥力的有效措施。

Abstract:Based on a long-term field experiment,the effects of conventional tillage(T),no-tillage without wheat stubble mulching(NT) and no-tillage with wheat stubble mulching(NTS) on soil aggregates size distribution and stability of winter-wheat field were studied.The results showed that NTS significantly increased the soil bulk density of plough layer and the organic matter of top layer.Compared with the background values in 2004,macro-aggregates significantly increased in NTS,was 14.88% and 6.40% higher than that...

Abstract:调查采集长江荆江段湿地围垦农田土壤的表土样品,实验室分析总有机碳(SOC)、热水溶性有机碳(HWEC)、颗粒态有机碳(POC)、易氧化有机碳(LOC)及有机碳键合组分含量特征,比较分析不同土地利用方式下湿地起源土壤有机碳组分的变化。结果表明,棉田土壤总有机碳含量为(8.86±0.73)g/kg,桔园的为(9.07±0.01)g/kg,湿地的为(10.30±0.37)g/kg,稻田的为(15.57±1.92)g/kg。即棉田和桔园的总有机碳含量接近于湿地的,而稻田的较大幅度高于前面旱地和湿地的。同时,稻田的热水溶性有机碳含量显著高于棉田的(p<0.05);颗粒态有机碳含量显著高于桔园的(p<0.05);易氧化有机碳含量变化与总有机碳一致。但是,从不同组分比率来说,湿地、稻田、棉田间HWEC/SOC、POC/SOC和LOC/SOC均无显著差异(p>0.05),而桔园HWEC/SOC显著高于其他利用方式的(p<0.05),棉田POC/SOC显著高于桔园的(p<0.05),桔园LOC/SOC显著高于湿地的(p<0.05)。供试土壤中铁铝键合态有机碳含量均显著高于相应钙键合态有机碳(p<0.05),且后者在不同土地利用...

Abstract:A long-term(19-year) fertilization experiment was conducted to study the effects of different fertilization system on soil carbon stock and fractions.The results showed that effect of different long-term fertilization on soil carbon stock and fractions was significant.Contents of soil total organic carbon(TOC) in different fertilizations decreased in an order of combined manure and inorganic fertilizer(average 12.34 g/kg)>single organic fertilizer(average 12.15 g/kg)>no fertilizer(average 10.56 g/kg)>single...

Abstract:Soil particle-size distribution is one of the most important physical attributes due to its strong influence on soil properties related to water movement,productivity and soil erosion.The monofractal and multifractal characteristics of soil particles and their correlation with soil organic matter(SOM) under different land use patterns in lowlands of the Yellow River Delta were studied with the monofractal and multifractal theory and methods.The results showed that the monofractal dimension D of different la...

Abstract:Experiments were conducted with the field investigation,pot and field experiments to study the magnesium supply status of main soil types and effects of Mg fertilizer on yield and quality of crops in Shanxi province.The results showed that the average content of exchangeable Mg in top soils(0-20 cm) of main types of soils in Shanxi province was 255.1 mg/kg,varied from 78.1 to 641.8 mg/kg.The order of exchangeable Mg content in different type soils was fluvo-aquic soil >cinnamon soil >chestnut-cinnamon soil ...

Abstract:within investigating and water holding experiment indoors to the four species(Agropyron mongolicum,Glycyrrhiza uralensis,Leymus secalinus,and Artemisia desertorum) of representative plant community in desert steppe,using the methods of the mathematical statistics,and gained the hydrological features parameters including the capita storage,the maximum capita storage of water holding,water absorption rate and etc.The results showed that enclosure and grazing prohibition on the different capita storage of plan...

Abstract:A pilot study of hydrological effect s of litters layer and soil layer was carried out in four kinds of forest stands in Beigou forest farm,Hebei province.The result showed:(1)The litter total storage capacity of Larix principis-rupprechti mixed Chinese pine was 12.28 t/hm2,the maximum water capacity was 24.60 t/hm2,the modified interception amount was 27.19 t/hm2;the litter total storage capacity of Chinese pine was 11.74 t/hm2,the maximum water capacity was 19.30 t/hm2,the modified interception amount was...

Abstract:By setting plastic mulching(PM),1 500,4 500,7 500,and 10 500 kg/hm2 of straw mulching quantiy respectively(SM15,SM45,SM75 and SM105),also setting no mulching as control treatment(CK) in winter wheat field,under simulated rainfall situation,the influence of different covering methods on soil evaporation,soil moisture and rainfall storage by soil were studied.The results indicated that the daily variations and daily cumulative of soil evaporation had the same trend in all treatments;the difference of soil eva...

Abstract:Dew is one of important environmental factors for desert ecological system in semiarid and arid regions.In this study,the artificial crusts were selected for experimental objects to compare differences of dew condensation amounts between different artificial crusts by means of daily detection for dew condensation on artificial crust surfaces.Concerning the experiment,artificial cyanobacterial crusts(ACC),artificial algal crusts(AAC),artificial moss crusts(AMC),and natural moss crusts(NMC) as well as shiftin...

Abstract:Ginseng yield is decided soil physicochemical environment of ginseng growth.Good soil composition can avoid soil erosion.Soil structure and keep water character of ginseng soils was studied,the reasons of old ginseng soil physical properties worsen was analyzed,the particle composition of ginseng bed soil were measured.The percentage of dry granule,wet granule,water stable aggregate,micro-aggregates in the ginseng bed soil were measured and computed.Rupture structure ratio of the ginseng bed soil was calcul...

Abstract:Soil infiltration characteristic and its influencing factors were studied under five land-cover types in gully drainage areas in Yuanmou dry-hot valley region in this paper.Results indicated that:(1)Differences on soil infiltration capacity among the five land-cover types were significant,especially for the bare land A and bare land B,whose infiltration capacities were much more lower than those of the other three types,which probably is one of the reasons that the corresponding gully heads were still activ...

Abstract:In order to study optimal allocation of land and water resources consider the ecological security,this paper calculated the dynamic eco-environmental water demand by using hydrological indexes as control on ecological safety,and established the optimization model with of land and water resources as the goal to make economic and social benefits relatively optimal,by using the improved colony algorithm to optimize configuration calculation.The results show that: It can calculate the dynamic allocation result ...

Abstract:A pot experiment was conducted to study the effect of application of different amount of red mud on rice yield and the soil biological properties in Cd-polluted paddy soil,with no red mud application as the control(RM-0).The results indicated that appropriate application of red mud could apparently promote rice growth and increase effective panicles and rice yield.With no red mud application as the control(RM-0),plant height,effective panicles,seed setting rate and rice yield in RM-2 treatment(0.5% red mud)...

Abstract:Phytoremediahon is a promising new method that is used green planted to take up or deloxify Cd from contaminated soils.With soybean(Glycine max),cotton(Gossypium hirsutum),dutura(Dature stramonium Datura),castor oil plant(Ricinus communis) and maize(Zea mays) as materials,soil column culture experiment was used to study differences of root activities,Cd accumulation in organs,rizhospheritic soil enzymes activities and soil nutrition contents of five plants under Cd(5 mg/kg) stress.The results indicated:(1)U...

Abstract:Taking Panggezhuang town,Daxing district sewage treatment plant's composting sludge,raw sludge,and Tongzhou local mellow soil as an example,This paper explores the dynamic changes of the sludge mixed soil leachate index.The results show that,the pH of mixed soil was reduced,and the soil total nitrogen,total phosphorus content of mixed soil were increased,also increased soil heavy metals As,Cd,Ni,Cu,Pb content,the heavy matal Pb in raw sludge series leachate maybe takes the most important part in polluting t...

Abstract:To confirm the effects of soil copper and sulfur pollution on growth of young apple trees,the young apple trees which were planted in the flood land filled by pyrite iron sand were used as materials to study the effects of soil copper and sulfur contents on growth of young apple trees.The results showed that:The growth of apple trees would be inhibited when the soil copper content was more than 46.8 mg/kg and the soil available sulfur was more than 368.7 mg/kg.The apple trees would be poisoned or death when...

Abstract:through the field sampling,test in lab.and mathematical statistics,researched on the lead,cadmium of soil under different land-use types in before in vegetable field planning area of Beibei.The results showed that:(1)Through descriptive statistics and analysis of variance,under the different land-use types the total cadmium and lead,the contents of available lead and cadmium,the bioavailability index of cadmium and lead had different degree of difference.And the different land-use types had different degree...

Abstract:Through field investigation,three pioneer species,Miscanthus floridulus,Polygonum flaccidum Meissn.and Lespedeza cuneata,lived in lead/zinc mine tailings pond of Huayuan in Xiangxi were found.The physical and chemical properties of the soil,the uptake and translocation of Pb,Zn and Cd in pioneer species and heavy metal forms change and properties in rhizosphere soils were studied.The results showed that the inhabitation of the three pioneer species could improve the content of organic matter,total nitrogen ...

Abstract:In the natural rainfall condition,this paper studied the characteristics of the output surface runoff of TN,TP,dissolved inorganic-N(NH+4-N,NO-3-N) and dissolved phosphorus(DP) in four different land types of the Jianshan river basin of Chengjiang,and analyzed the nutrition restriction and the eutrophication risk of the output runoff of four land types by utilizing the ratios of TN/TP,inorganic-N/DP,NO-3-N/DP,NH+4-N/DP.The results showed that the ability of preventing soil nutrients loss differed in the dif...

Abstract:The author researched about the pollution condition of root soil and heavy metal accumulation characteristics of 13 kinds of dominant plants naturally settled or human cultivated in the Dabaoshan mine.The results showed that soil in Dabaoshan mine was polluted by heavy metal Cd,Pb,Zn and Cu,especially by Cd and Cu.In this research,the Pb content of aerial parts of Panicum repens reached 1 214.00 mg/kg;the Cu content of Paulownia fortunei leaves reached 1 024.80 mg/kg,both of which were more than 1 000 mg/kg...

Abstract:Chemical fertilizer and herbicide are widely used in agricultural production.These chemical substances not only significantly increase crop yields but also result in serious water pollution.This study was conducted to evaluate the effects of three practices(no-tillage,grass hedges,no-tillage and grass hedges) on the loss of nitrogen,phosphorus and atrazine with runoff.The results showed that no-tillage and grass hedges significantly reduced agricultural non-point source pollution.As compared to the control,...

Abstract:Heavy metal always has great influence on sludge treatment,sometimes even decides the technical route selection.Based on the content and output of extraction of heavy metal from the sludge of three municipal wastewater treatment plants in Xi'an,this paper analyzed the relevant standards about sewage sludge disposal and hazardous waste treatment.The results showed that the policy and standards for sludge disposal lacked adequate attention to transformation property of heavy metal.Further,a series of standard...

Abstract:Change characteristic of the typical residual solonchak in the northern of Xinjiang were explored,through investigating soil profile salt on different reclaimed years.Baojiadian town in the mamas' river watershed was considered as research area,researching dynamic change of soil salinity and its influencing factors by using methods of traditional statistical and temporal-spatial conversion.The results showed that the salinity of soil profile,with the extension of reclaimed years,was significantly decreasing...

Abstract:In situ field experiment combined with venting method was conducted to study the ammonia volatilization from the biogas slurry(BS) and chemical fertilizer applied paddy field and their difference.The field experiment designed four treatments with three replications according to applied nitrogen(N) quantities,i.e.,270 N kg/hm2(I-F) from urea,and 270(I-B),540 and 1 080 N kg/hm2 from BS.The amount of BS or fertilizer for each treatment was finished for application in three times with ten days intervals.The res...

Abstract:Taking pioneer plant Neyraudia reynaudiana on soil and water conservation as test material,with pot experiment test for four level drought stress to study the effects of photosynthetic characteristics of Neyraudia reynaudiana with photosynthetic pigments,chlorophyll fluorescence parameters and photosynthetic parameters.Results showed that chlorophyll content of Neyraudia reynaudiana increased and chlorophyll a/b decreased under moderate and mild drought stress.Chlorophyll fluorescence parameters F0,Fm,Fv in...

Abstract:The 2-year-old Yucca brevifolia seedlings were processed by using different ways of low temperature overwintering test,their degree of freezing injury and physiological and biochemical indexes were determined.The results show that as the severity of freeze injury,the content of the membrane permeability and the free proline and the soluble sugar gradually increased,the content of chlorophyll gradually decreased.The severity of freeze injury of soil covering container seedlings is the most serious,the conten...

Abstract:The experiment took the fly ash and superfine phosphate powder as the coated material,and made two kinds of coated slow-release urea(CSRU) with different coating thickness to study the effects on the growth of Chinese cabbage in field experiments.The experiment results showed that coated slow-release urea could significantly increase the plant biomass,photosynthetic rate,transpiration rate,total N,P and K,POD,SOD and CAT activity than those of CU,and other indicators were no less than those of CU.Different ...

Abstract:Four homemade compound fertilizers with nitrification inhibitor dicyandiamide(DCD) being ratio 0%,1%,2% and 4%,separately were prepared out of common compound fertilizer by coating them with fly ash as major material.Soil incubation experiment and field experiment were used to study N-release characteristics of the fertilizers and their effects on Chinese cabbage.Results showed that:(1)Using four kinds of fertilizers could keep N as NH+4-N for a long time,consequently,reduce the risk of nitrate N losses.The...

Abstract:采用批平衡法研究我国2种典型土壤对镉和铅的吸附特性及其与温度的关系,运用热力学参数ΔG°、ΔH°和ΔS°解释土壤镉和铅的吸附机理,并对镉和铅在复合共存情况下的吸附特性进行讨论。结果表明,镉和铅在土壤中的吸附过程表现出明显的非线性,镉和铅的吸附分别符合Freundlich模型和Lang-muir模型。塿土对镉和铅的最大吸附量和最大缓冲容量均大于红壤的。镉和铅复合共存时,2种重金属的吸附均受到抑制;温度升高时,镉和铅对彼此的抑制作用有所减弱。吉布斯自由能变ΔG°为负值表明镉和铅吸附反应为自发反应;ΔH°为正值表明土壤对镉和铅的吸附为吸热反应。单一存在时,镉在塿土和红壤中的主要作用力分别为氢键和范德华力;而铅在塿土和红壤中的主要作用力均为范德华力。复合共存时,镉和铅的主要作用力发生改变。

Abstract:Under the low potassium solution and soil cultures conditions,capability of enrichment in potassium of 16 different genotypes in genus Houttuynia Thunb.were screened by comparing the potassium contents,potassium uptakes and utilization ratios,and the morphology characters of root.H.cordata was cultured under low and normal potassium solution conditions,the result showed that the genotype of H.emeiensis Z.Y.Zhu et S.L.Zhang(W01-86),H.cordata(W01-34 and W01-71) had high capability of enrichment in potassium,t...