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Influence of Chlorsulfuron Contamination on Ratios of Biomass Carbon and Nitrogen to Total Organic Carbon and Nitrogen in Soil

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Pedosphere 2000年第2期10卷 189-192页

作者： A. M. EL-GHAMRY HUANG CHANGYONG and XU JIANMING(college of natural resources and environmental sciences, zhejiang university, hangzhou 310029 china) sych.utoronto.ca

The extent and seriousness of the contamination of soils by pesticides still remain to be determined,In agricultural systems,herbicides are the largest class of pesticides used (Shea,1985),Chlorsulfuron is one of the most important sulfonylurea herbicides with important feature of very high herbicidal activity,which results in extremely low application rates of 10-40g ha^-1(Blair and Martin,1988),The sulfonylurea herbicides can persist in the soil for more than 1 year(Brown,1990),Therefore,there has been considerable interest in the side effects of these chemicals on non-target organisms,including soil microorganisms(Greaves and Malkomes,1980),It ios generally recognized that the microbial biomass is the eye of the needle through which all organic materials that enter the soil must pass(Jenkinson,1988), Changes in the microbial biomass-C(Cmic) can provide an early indication of long-term trends in the total organic-C(Corg) of soils(Carter,1986),The Cmic/Corg ratio has been found useful as an index of changes in soil organic matter resulting from land management changes(Hart et al.1989).Many studies were done on relative effect of heavy metals on the ratio of Cmic/Corg but few studies have laid particular attention to the effect of herbicides on this ratio,The present paper reports on the Cmic/Corg and microbial biomass-N/total N (Nmic/Ntotal)ratios in soil as affected by chlorsulfuron.

关键词：有机碳有机氮氯磺酮土壤污染生物体

Effects of heavy metal pollution on soil microbial biomass

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Journal of environmental sciences 1999年第1期11卷 44-51页

作者： K. S. Khan, Huang Chang yong college of natural resources and environmental sciences, zhejiang Agricultural university, hangzhou 310029, china

This paper reviewed the effects of heavy metals on microbial biomass in metal polluted soils. Laboratory and field investigations where metals were applied as inorganic or organic salts demonstrated a significant decline in the size of soil microbial biomass. In most of the cases, negative effects were evident at metal concentrations below the European Communitys (EC) current permissible metal levels in the soil. Application of metal enriched sludges and composts caused significant inhibition of microbial biomass at surprisingly modest concentrations of metals in the soil that were indeed smaller than those likely to decrease the growth of sensitive crop species. On the whole, relative toxicity of metals decreased in the order of Cd>Cu>Zn>Pb, but a few exceptions to this trend also existed. A significant decline in the biomass carbon to organic carbon ratio(C min /C org ) in metal polluted soils indicated that this parameter can serve as a good indicator of the toxicity of metals on soil microflora. The knowledge regarding the response of soil biota to metal interactions and the factors affecting metal toxicity to soil microorganisms is still very limited and warrants further study.

关键词： heavy metal pollution soil microbial biomass.

Effect of acetate on lead toxicity to microbial biomass in a red soil

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Journal of environmental sciences 1999年第1期11卷 90-96页

作者： K. S. Khan, Huang Chang yong college of natural resources and environmental sciences, zhejiang Agricultural university, hangzhou 310029, china

A laboratory incubation experiment was conducted to elucidate the effect of acetate on lead bioavailability and toxicity to microbial biomass in a red soil. Results indicated that the application of acetate along or at the lower lead levels of 100 and 200 μg/g soil stimulated the soil microbial biomass. The addition of acetate at the higher lead levels of 300, 450 and 600 μg/g soil caused significantly greater reductions in the biomass carbon(C mic ) and the biomass nitrogen (N mic ), compared with the control or the same lead levels applied individually. A greater increase in the biomass C:N ratio occurred by acetate addition at the same lead levels. The concentration of 0.01 mol/L CaCl 2 extractable lead was considerably higher in the lead plus acetate treatments than at the same lead levels with no acetate. Based on these results, it was concluded that the application of acetate might have suppressed the lead adsorption in the soil which in turn resulted in its more bioavailability and hence more toxicity to the soil microbial biomass.

关键词： acetate lead toxicity microbial biomass red soil.

Phosphate Rock Fertilizer in Acid Soils: Comparing Phosphate Extraction Methods for Measuring Dissolution

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Pedosphere 1998年第3期8卷 273-279页

作者： T. S. ANSUMANA KAWA and WANG GUANGHUO Department of Soil Science and Applied Chemistry, college of natural resources and environmental sciences, zhejiang Agricultural university, hangzhou 310029 (china) (Received March 13, 1998 revised April 22, 199 Department of Soil Science and Applied Chemistry College of Natural Resources and Environmental Sciences Zhejiang Agricultural University Hangzhou 310029 China

Three phosphate extraction methods were used to investigate the dissolution, availability and transformation of Kunyang phosphate rock (KPR) in two surface acid soils. Dissolution was determined by measuring the increase in the amounts of soluble and adsorbed inorganic phosphate fractions, and did not differ significantly among the three methods. Significant correlations were obtained among P fractions got by the three extraction methods. Dissolution continued until the end of the 90 day incubation period. At the end of the period, much of the applied phosphate recovered in both soils were in the Al and Fe P or in the hydroxide and bicarbonate extractable inorganic P fractions. The dissolution of KPR in the two soils was also similar: increased addition of phosphate rock resulted in decreased dissolution. The similarity in the order and extent of dissolution in the two soils was probably due to the similarity in each soil of several factors that are known to influence phosphate rock dissolution, namely low CEC, pH, P level, and base status; and high clay and free iron and aluminum oxide contents. The results suggested that KPR could be an alternative P source in the long, if not the short, term in the soils, provided that those factors influencing P availability in the soils are not limiting.

关键词： alternative source of phosphate fractionation phosphate rock

Effects of methamidophos and glyphosate on copper sorption-desorption behavior in soils

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Science china(Life sciences) 2005年第Z1期48卷 67-75页

作者： YU Ying, ZHOU Qixing & HE Zhenli Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of sciences, Shenyang 110016, china college of natural resources and environmental sciences, zhejiang university, hangzhou 310029, china Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China college of natural resources and environmental sciences Zhejiang University Hangzhou 310029 China

A batch-equilibration technique was employed to study the impact of two organophosphorus pesticides methamidophos (MDP) and glyphosate (GPS) on copper (Cu2+) sorptiondesorption for phaeozem and burozem collected from Northeastern china. The addition of the two pesticides decreased Cu2+ sorption, increased Cu2+ desorption and prolonged the equilibrium time of Cu2+ sorption-desorption. But GPS appeared to exert a stronger influence on Cu2+ sorption-desorption due to its stronger complexion with Cu2+. When MDP was added, Cu2+ sorption-desorption was linearly correlated with MDP treatment concentrations. But in the presence of GPS, Cu2+ sorption first underwent a rapid decrease period, and then slowly tended towards a steady period. The reverse pattern could be found for Cu2+ desorption in the presence of *** pesticides and with the existence of MDP, Cu2+ sorption-desorption kinetics was well conformed to two-constant equation and Elovich equation. But that was not the case for Cu2+ desorption kinetics in the presence of GPS although its sorption could be also described by these two equations.

关键词： Cu, sorption, desorption, methamidophos, glyphosate, phaeozem, burozem.

不同施肥处理对水稻养分吸收和稻田土壤微生物生态特性的影响

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土壤学报 2005年第1期42卷 116-121页

作者：张奇春王光火方斌浙江大学环境与资源学院杭州310029

在水稻长期定位肥料试验条件下研究了不同施肥处理对水稻养分吸收动态变化和土壤微生物生态特性的影响。该长期定位试验设有CK(不施肥对照)和PK、NK、NP、NPK五个肥料处理和常规稻、杂交稻品种对比处理。研究结果表明,水稻产量分别与水... 详细信息

在水稻长期定位肥料试验条件下研究了不同施肥处理对水稻养分吸收动态变化和土壤微生物生态特性的影响。该长期定位试验设有CK(不施肥对照)和PK、NK、NP、NPK五个肥料处理和常规稻、杂交稻品种对比处理。研究结果表明,水稻产量分别与水稻吸氮总量、吸磷总量和吸钾总量显著相关;在连续种植水稻条件下,水稻对所缺养分的吸收量呈逐年下降趋势,表明缺肥区土壤相应的有效养分库消耗很快。土壤微生物特性测定表明,不平衡施肥降低了土壤微生物量N,使微生物量C/N比增加。与缺肥区相比较,NPK配施处理促进了土壤微生物的功能多样性,同时增加了土壤微生物总量。可见,土壤中养分不足或供应不平衡,不仅影响水稻养分的吸收,而且对土壤微生物总量和群落多样性产生重要影响。

关键词：水稻产量土壤微生物施肥处理养分吸收缺肥稻田土壤长期定位总量增加供应

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磁性参数在红壤退化评价指标中的应用

土壤通报 2003年第1期34卷 21-24页

作者：韩晓非柳云龙陈永强俞立中华东师范大学地理系上海200062 浙江大学环资学院资科系浙江杭州310029

选择浙西金华地区兰溪实验观测站六种不同退化程度的红壤为研究对象 ,分析了反映红壤退化程度的物理、化学和生物指标及红壤磁测参数与它们之间的内在联系。结果表明 ,磁性参数与反映红壤退化程度的理化及生物指标均有显著或较显著的相... 详细信息

选择浙西金华地区兰溪实验观测站六种不同退化程度的红壤为研究对象 ,分析了反映红壤退化程度的物理、化学和生物指标及红壤磁测参数与它们之间的内在联系。结果表明 ,磁性参数与反映红壤退化程度的理化及生物指标均有显著或较显著的相关性。退化程度较轻的香樟林和混交林表现了较低的细晶粒磁性矿物含量和较高的反铁磁性矿物含量 ,退化程度较高的杉木林、桔园、草地则相反 ,细晶粒磁性矿物含量较高且亚铁磁性矿物的相对含量上升。磁性参数和土壤理化生物指标之间良好的相关性表明 ,磁性参数可以作为指示红壤退化程度的重要指标。

关键词：评价指标应用红壤土壤磁性参数土壤退化

Phosphorus Concentration and Forms in Surface and Subsurface Drainage Water from Wetland Rice Fields in the Shaoxing Plain

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Pedosphere 2003年第3期13卷 239-248页

作者： ZHANG MINGKUI, JIANG HONG and LIU XINGMEIDepartment of Resource sciences, college of Resource and environmental sciences, zhejiang university, hangzhou 310029 (china) Department of Resource sciences College of Resource and Environmental Sciences Zhejiang University Hangzhou 310029

Phosphorus (P) is the limiting factor for eutrophication in most freshwater ecosystems. In china, Ptransported from intensively cultivated land has been reported as an important source of P in surface *** this study, we investigated P concentration and forms in surface and subsurface drainage from wetland ricefields in the Shaoxing plain, zhejiang Province, china. From selected rice fields, surface drainage sampleswere collected at rice-growing, non-growing and fertilization periods, and subsurface drainage samples atdrought and rewetting (irrigation or precipitation after 5～10 d drought period in the surface soils) and wet(drainage under long-term wet soil condition) periods. Water samples were characterized for their totalreactive P (TRP), dissolved reactive P (DRP) and particulate reactive P (PRP). Concentrations of the TRPand DRP in the surface drainage ranged from 0.08 to 1.50 and 0.06 to 1.27 mg L-1, respectively. The TRPand DRP were dependent on field operation activities, and decreased in the order of fertilization period ＞rice-growing period ＞ non-growing period. Phosphorus concentration of runoff receiving P fertilizer can bean environmental concern. The PRP concentration in the surface drainage, ranging from 0.01 to 0.57 mgL-1, accounted for 8%～78% of the TRP. Concentration of the TRP in the subsurface drainage was from0.026 to 0.090 mg L-1, consisting of 29%～90 % of the DRP and 10%～71% of the PRP. In the droughtand rewetting period, the PRP accounted for, on average, 63% of the TRP, much higher than in the wetperiod (23%), suggesting that there was transport of P in preferential flow during drainage events after ashort-term drought period in the surface soils. Therefore, P losses in particulate form may be importantin the subsurface drainage from rice fields when surface soils form cracks and favor rapid flow downwardthrough the soil profiles, suggesting the important role of water-dispersible colloid particles in mediating andco-transporting P in

关键词： drainage phosphorus wetland rice field

Quantification of the effects of management factors on maize (Zea mays L.) and cotton(Gossypium hirsutum L.) residues decomposition rate

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Journal of environmental sciences 2002年第2期14卷 165-172页

作者： JONES Chilima, HUANG Chang yong, WU Ci fang (college of natural resources and Environment, zhejiang university, hangzhou 310029, china. college of natural resources and Environment Zhejiang University Hangzhou 310029 China

Efforts to quantify management effects on decomposition rate of added substrates to the soil is important especially where such information is to be used for prediction in mathematical or simulation models. Using data from a short term (60 days) greenhouse simulation study, a procedure for quantifying effects of management on SOM and substrate decomposition is presented. Using microbial growth rate u (q), microbial efficiency in substrate utilization e (q), specific decomposition rates for added plant residues to two contrasting soils, red earth (Ferrasol) and black earth (Acrisol) were estimated. The treatments included straw addition + buried, (T1); straw addition + mineral N (T2); and straw addition + tillage, (T3). Sampling was done every 15 days. Straw decomposition rate was affected by external mineral N sources (Urea 46% N). Addition of an external N source significantly increased decomposition rates. The study could not, however, fully account for the effect of tillage on residues because of the limited effect of the tillage method due to the artificial barrier to mechanical interference supplied by the mesh bags. It is concluded that using few decomposer parameters, decomposition rates and consequently SOM trends in a soil system can be monitored and quantification of the influence of perturbations on decomposition rate of added substrates possible.

关键词： management factors residue decomposition rate maize cotton red soil black soil