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1.
不同土壤培肥措施对华北高产农田原生动物丰度的影响   总被引:5,自引:0,他引:5  
曹志平  陈国康  张凯  吴文良 《生态学报》2005,25(11):2992-2996
为了解华北高产农田生态系统中秸秆还田、有机肥和化肥投入水平等土壤培肥措施对原生动物群落丰度的影响,1999年10月~2000年9月在山东桓台冬小麦套种夏玉米的田间试验中进行了取样分析。田间处理1~处理9,依序为:全还,麦还,全还 化肥1,麦还 化肥1,全还 化肥2,麦还 化肥2,全还 化肥3,麦还 化肥3和全还 化肥1 有机肥处理。应用3级10倍环式稀释培养法对土壤中鞭毛虫、纤毛虫、肉足虫3类群原生动物的丰度进行了测定。结果显示:该研究地块肥力状况良好;土壤鞭毛虫和肉足虫占有绝大比例,分别为总丰度的39.47%和59.22%,纤毛虫仅占1.31%;土壤原生动物丰度在不同培肥处理中表现出相似的季节性动态变化特征;比较不同土壤培肥措施条件下的原生动物丰度水平为:全还>麦还,全还 化肥1 有机肥>麦还 化肥1,麦还 化肥2,麦还 化肥3>全还 化肥1,全还 化肥2,全还 化肥3;化肥对原生动物丰度表现出明显的抑制作用,而有机肥对原生动力丰度表现出明显的促进作用。化肥的施用量水平对土壤原生动物丰度的影响无显著性差异,作物秸秆采取何种还田方式对土壤原生动物丰度的影响也是不显著的,如麦还 化肥培肥地块的原生动物丰度仅略高于全还 化肥。  相似文献   

2.
典型POPs物质对土壤原生动物丰度的影响   总被引:3,自引:0,他引:3  
采用“三级十倍环式稀释法(three level ten-fold dilution method)”的方法,对取自添加了DDT、林丹的盆栽实验土壤中的原生动物丰度进行研究分析,以此作为典型POPs物质对土壤原生动物的抑制效应的初步探索性研究。实验发现,在添加了DDT、林丹的土壤中的原生动物的丰度与对照相比有大幅度的下降,其种群结构遭到了相当大的破坏。其中作为优势类群的鞭毛虫、肉足虫平均数量最小时仅为CK对照的0.3%、2.5%,而对污染最为敏感的纤毛虫则在土壤中完全消失。研究结果表明,受典型POPs物质污染的土壤,即使其含量很低,也对原生动物的抑制作用非常显著。  相似文献   

3.
哈尔滨人工湖泊中原生动物群落变化规律   总被引:9,自引:2,他引:7  
谭晓丽  施心路  刘桂杰  白昕 《生态学报》2005,25(10):2650-2657
2003年3月~2004年2月调查了哈尔滨人工湖泊原生动物群落多样性的变化规律,应用PFU法研究了原生动物群落季节变化演替的特征。共观察到各类原生动物120种,其中鞭毛虫53种,占原生动物总数的44%,肉足虫9种占原生动物总数的8%,纤毛虫58种占原生动物总数的48%,分析了原生动物在该湖的组成特点。原生动物在此人工湖泊中1个周年内的表现规律为植物性鞭毛虫多,动物性鞭毛虫少;纤毛虫多,肉足虫少。原生动物群落的结构参数(种类组成、个体丰度和多样性指数)因水质的变化而发生变化。在此湖中原生动物的优势种为喇叭虫属(S tentor)、眼虫属(E ug lena)、游仆虫属(E up lote)、隐滴虫属(C ryp tom onas),常年的居留种为眼虫属(E ug lena)、弹跳虫属(H a lteria)、侠盗虫属(S trobilid ium)、隐滴虫属(C ryp tom onas)。全年3个采样站的生物多样性指数在1.912~7.473之间。原生动物在1个周年中平均个体丰度出现的规律依次递减的顺序是秋季、夏季、春季、冬季。采样站1的平均个体丰度在四个季节中均高于采样站2、3。  相似文献   

4.
中国典型地带土壤原生动物:Ⅱ生态学研究   总被引:1,自引:0,他引:1  
研究了中国典型地带土壤原生动物生态学。结果表明,在各典型地带中,凋落物层原生动物的年平均现存量以温带(吉林长白山)和暖温带(北京小龙门)的为最大,北热带(云南西双版纳)的次之,中热带(海南尖峰岭)的最小;0~5cm土壤层的原生动物年平均现存量以暖温带和北热带的为最大,亚热带(武昌珞珈山)和温带的次之,高寒带(青海海北)和中热带的最小。各地带各样点凋落物层的原生动物现存量均大于0~5cm土壤层的。从丰度来看,在原生动物三大类群中,肉足虫现存量最大,鞭毛虫次之,纤毛虫现存量最小。各地带各样点的原生动物丰度高峰一般都出现在夏季。回归分析结果表明,土壤含水量、温度、pH值和有机质、总氮、总磷及总钾含量对土壤原生动物丰度均有显著影响。  相似文献   

5.
2005年4月-2006年3月调查了杭州市郊下沙区一个沼泽性水域原生动物群落的变化规律。共观察到各类原生动物265种,其中鞭毛虫114种,占原生动物总数的43%,其中植物性鞭毛虫占91%,动物性鞭毛虫仅占9%;肉足虫34种,占原生动物总数的13%,纤毛虫117种,占原生动物总数的44%。原生动物在此水域1个周年内的分布特征表现为植物性鞭毛虫种类多于动物性鞭毛虫,纤毛虫种类多于肉足虫种类。原生动物群落的结构参数(种类组成、个体丰度和多样性指数)因水质的变化而变化。此水域原生动物的优势种为梨形扁裸藻(Phacus pyrum)、旋转囊裸藻(Trachelomonas volvocina)、绿色裸藻(Euglenaviridis)和刺鱼状裸藻(Euglena gasterosteus),常年居留种为裸藻(Euglenasp.)、奇形扁裸藻(Phacus anomalus)、钟形虫(Vorticellasp.)、尾草履虫(Paramecium caudatum)和多态喇叭虫(Stentor polymorphrus)。全年3个采样站的Margalef生物多样性指数为1.056~6.054。  相似文献   

6.
甲基溴消毒对番茄温室土壤食物网的抑制   总被引:1,自引:0,他引:1       下载免费PDF全文
陈云峰  曹志平 《生态学报》2010,30(24):6862-6871
甲基溴熏蒸作为一种控制土传病害的技术,不仅对大气臭氧层有破坏作用,而且对土壤中的有益生物也有不利影响。2005-2006年,对山东省寿光市番茄温室土壤进行甲基溴(50 g/m2)熏蒸,调查甲基溴熏蒸对土壤食物网结构和功能群的影响。结果表明:甲基溴熏蒸显著抑制了土壤微生物生物量C及微生物生物量N,减少了原生动物(鞭毛虫、纤毛虫、肉足虫)、线虫(根结线虫二龄幼虫、食细菌线虫、食真菌线虫、食植物线虫、杂食性线虫)及螨类的丰度。在整个番茄生长期间,与对照相比,微生物生物量C、微生物生物量N、原生动物总丰度、线虫总丰度、螨总丰度分别下降了45.9%、44.8%、9.5%、93.6%、895%。熏蒸后,土壤食物网功能群数目、联通度、食物链最大长度和平均长度均降低。由此可见, 甲基溴熏蒸后抑制了土壤中的生物,使整个食物网结构更简单。  相似文献   

7.
研究了添加秸秆碳源在连续种植条件下对根结线虫病害严重土壤中微生物生物量和原生动物丰富度的影响.供试作物为番茄,设置3个梯度的小麦秸秆添加量[1N(2.08g·kg-1)、2N (4.16g·kg-1)和4N(8.32 g· kg-1)].结果表明:添加秸秆碳源对微生物生物量碳、氮和原生动物丰富度具有显著影响,且这种影响呈现为4N>2N>1N>CK.添加秸秆碳源对原生动物群落结构也具有显著影响,各处理鞭毛虫、肉足虫和纤毛虫的平均比例分别为36.0%、59.5%和4.5%.在相同秸秆添加量下,土壤微生物量碳氮、微生物碳氮比和原生动物丰富度随种植年限的延长而提高.  相似文献   

8.
中国典型地带土壤原生动物::I.区系特征和物种分布   总被引:11,自引:1,他引:10  
研究中国典型地带土壤原生动物区系特征和物种分布。结果表明,鞭毛虫以波豆虫类和变形鞭毛虫类种类最多,其次为金滴虫类和无色眼虫类。肉足虫以有壳种类占优势,其中又以表壳目种类最多。纤毛虫最重要的3个类群为下毛目、肾形目和前口目,其中又以下毛目种类最丰富。凋落物层的种类多于0 ̄5cm土壤层,其原因在于凋落物层具有比0 ̄5cm土壤层更为优越的生态环境条件。290种原生动物中,中热带分布有72种,北热带106  相似文献   

9.
原生动物的捕食作用对水细菌的影响   总被引:12,自引:0,他引:12  
原生动物和水细菌关系密切 ,Sanders等[1] 指出无论在淡水或海洋生态系统中 ,细菌和鞭毛虫的数量有着较为稳定的比例 (约 10 0 0∶1)。由于细菌细胞富含N和P ,原生动物通过对细菌的捕食作用成为重要的无机盐再生者 ,因而在水体的物质循环中占据重要地位[2 ] 。原生动物是水细菌数量的主要调节者 ,它沟通了细菌与后生动物之间的食物链。原生动物中的三大类 :鞭毛虫、肉足虫、纤毛虫都有一些专门吃细菌的种类 ,如波豆虫属 (Bodo)、屋滴虫属 (Oikomonas)、鼻吻滴虫属 (Rhynchomonas)、领鞭毛虫类 (Choa…  相似文献   

10.
土壤原生动物对川滇高山栎恢复时间的响应及生长季动态   总被引:1,自引:0,他引:1  
青藏高原东缘生态环境脆弱,森林频繁遭到砍伐,生物多样性受到严重威胁,森林砍伐后的生态恢复成为研究热点。原生动物在生态恢复中作为指示生物起着重要作用。本文就未砍伐、砍伐后不同恢复时期(20年、10年和1年)生的川滇高山栎(Quercus aquifolioides)林的土壤理化性质和原生动物在生长季的变化进行比较研究,以探讨生长季不同月份、不同恢复期的原生动物数量变化规律,分析土壤理化性质与其相关性。结果表明:(1)恢复10年和1年的林地的鞭毛虫数量(193个/g干土,164个/g干土)显著高于原始林地(22个/g干土),肉足虫在恢复1年的林地中数量最多(600个/g干土),纤毛虫数量则随次生演替进程逐渐增多。(2)在生长季不同月份原生动物的数量呈先增加后减少的趋势。鞭毛虫和肉足虫的峰值分别出现在7月和8月,而纤毛虫的数量在7、8、9月明显高于6月。(3)原生动物数量与土壤理化性质密切相关。鞭毛虫数量与p H值呈显著正相关(P=0.019),纤毛虫数量与铵态氮(P=0.002)和碳氮比呈显著正相关(P=0.022),肉足虫数量与硝态氮(P=0.008)和碳氮比(P=0.016)呈显著负相关。结果显示,三种原生动物数量在生长季不同月份表现出较大的波动性,其数量变化受土壤理化性质等多种因素调控。纤毛虫数量对川滇高山栎林砍伐恢复有正响应,而鞭毛虫、肉足虫数量有负响应。  相似文献   

11.
This is the first extensive study of soil protozoa of arid lands. Twenty-six samples from litters, soils, termitaria, and a cyanobacterial crust, collected from central and south Australian arid lands, were analyzed for numbers and species of gymnamoebae, ciliates, and testacea. Amoebae ranged from 1,000-5,000/g of material, and were two orders of magnitude more abundant than ciliates. Both groups increased in abundance and species richness from bare soils through spinifex to mulga to chenopod vegetations. Testacea ranged 900-5,000/g with similar species richness throughout vegetations, but reached 11,900/g with a doubling of species in a refugium in Kings Canyon. The most prevalent species of amoebae, ciliates, and testacea were taxa associated with ephemeral and disturbed habitats (r-selection). The cyanobacterial crust might be considered a micro-refugium because it contained a number of non-encysting protozoa, including Thecamoeba sp. and Nassula picta, feeding on cyanobacterial filaments. The numbers and species richness of protozoa under shrubs were greater than in bare soils, supporting the resource island hypothesis that desert plants create soil heterogeneity by localizing soil fertility under their canopies.  相似文献   

12.
Estimating the growth potential of the soil protozoan community   总被引:4,自引:0,他引:4  
We have developed a method for determining the potential abundance of free-living protozoa in soil. The method permits enumeration of four major functional groups (flagellates, naked amoebae, testate amoebae, and ciliates) and it overcomes some limitations and problems of the usual 'direct' and 'most probable number' methods. Potential abundance is determined using light microscopy, at specific time intervals, after quantitative re-wetting of air-dried soil with rain water. No exogenous carbon substrates or mineral nutrients are employed, so the protozoan community that develops is a function of the resources and inhibitors present in the original field sample. The method was applied to 100 soil samples (25 plots x 4 seasons) from an upland grassland (Sourhope, Southern Scotland) in the UK. Median abundances for all four functional groups lie close to those derived from the literature on protozoa living in diverse soil types. Flagellates are the most abundant group in soil, followed by the naked amoebae, then the testate amoebae and ciliates. This order is inversely related to typical organism size in each group. Moreover, preliminary evidence indicates that each functional group contains roughly the same number of species. All of these observations would be consistent with soil having fractal structure across the size-scale perceived by protozoa. The method described will be useful for comparing the effects on the soil protozoan community of different soil treatments (e.g. liming and biocides).  相似文献   

13.
Dispersion and runoff of mine tailings have serious implications for human and ecosystem health in the surroundings of mines. Water, soils and plants were sampled in transects perpendicular to the Santiago stream in Zimapan, Hidalgo, which receives runoff sediments from two acidic and one alkaline mine tailing. Concentrations of potentially toxic elements (PTE) were measured in water, soils (rhizosphere and non-rhizosphere) and plants. Using diethylenetriaminepentaacetic acid (DTPA) extractable concentrations of Cu, Zn, Ni, Cd and Pb in rhizosphere soil, the bioconcentration and translocation factors were calculated. Ruderal annuals formed the principal element of the herbaceous vegetation. Accumulation was the most frequent strategy to deal with high concentrations of Zn, Cu, Ni, Cd and Pb. The order of concentration in plant tissue was Zn>Pb>Cu>Ni>Cd. Most plants contained concentrations of PTE considered as phytotoxic and behaved as metal tolerant species. Rorippa nasturtium-aquaticum accumulated particularly high concentrations of Cu. Parietaria pensylvanica and Commelina diffusa, common tropical weeds, behaved as Zn hyperaccumulators and should be studied further.  相似文献   

14.
The polar desert soils of the McMurdo Dry Valley region support a limited water film community dominated by flagellates, amoebae, and nematodes. This study describes the protozoa and compares their distribution to nematodes. In 50 samples collected from 12 locations, rotifers and tardigrades were infrequent, and ciliates and testacea were rare. Soil protozoa occurred at all sites but the dominant nematode, Scottnema lindsayae (Timm 1971), did not, indicating soil habitat factors limiting nematode distribution are not limiting to protozoa. In contrast to the nematode species, which are all endemic to Antarctica, there were no endemic protozoan morphospecies found in our samples. The protozoan abundance was several orders of magnitude greater than that of the nematodes, and the species diversity was much greater. Most of the protozoa grew better at lower incubation temperatures. The ubiquitous distribution of protozoa suggests their importance in soil food webs and nutrient cycling in the dry valleys.  相似文献   

15.
重庆溶溪锰矿区土壤重金属污染评价及植物吸收特征   总被引:17,自引:0,他引:17  
黄小娟  江长胜  郝庆菊 《生态学报》2014,34(15):4201-4211
对重庆溶溪锰矿尾渣堆积区土壤、优势植物以及周边农田土壤的重金属含量(Mn、Cd、Cu、Zn和Pb)进行测定分析,并以重庆市土壤背景值为评价标准,应用Hakanson潜在生态危害指数法对土壤中重金属的潜在生态危害进行了评价。结果表明:该锰矿尾渣堆积区土壤中Mn、Cd、Cu、Zn和Pb的平均含量分别为48382.5、3.91、79.97、131.23和80.68 mg/kg,受到Mn、Cd的严重污染,Mn为强或很强生态危害,Cd为极强生态危害,而Cu、Zn、Pb为轻微生态危害,各尾矿渣堆积区的综合潜在生态危害指数(RI)均远大于720,为极强生态危害。对优势植物重金属含量的分析显示,绝大部分植物地上部Mn、Cd含量都超出正常范围的上限值,而Cu、Zn和Pb含量基本都在正常范围内;根据植物对重金属的吸收特征,将植物分为三类:将重金属主要累积于地上部分的富集型,如垂序商陆(Phytolacca americana L.)和酸模叶蓼(Polygonum lapathifolium Linn.),适用于重金属复合污染土壤的植物修复;将重金属主要累积于根部的根部囤积型,如芒(Miscanthus sinensis Anderss.)和乌蕨(Stenoloma chusanum Ching);重金属含量较低的规避型,如黄花蒿(Artemisia annua L.)、长波叶山蚂蝗(Desmodium sequax Wall.)及钻形紫苑(Aster subulatus Michx.);后两种类型的植物可种植在重金属污染严重且使用价值相对较低的矿山废弃地上,同时规避型植物对于研究植物的重金属排斥机理具有重要价值。溶溪锰矿区周边农田土壤主要受到Cd的严重污染,Cd为很强或极强生态危害。  相似文献   

16.
Abundance and productivity of protozoa in chalk streams   总被引:4,自引:0,他引:4  
The distribution and abundance of protozoa in two chalk streams were studied. Particular attention was given to the ciliates and amoebae associated with the dominant submerged macrophyte, Ranunculus penicillatus . Highest numbers of protozoa occurred in habitats in the stream where the current velocity was reduced. Mean standing crops of ciliates, flagellates and amoebae were 32.5, 2.9 and 2.0 mg dry wt m−2 of stream bed respectively. Estimates of production and respiration rates by field populations of ciliates and amoebae were made for one type of habitat within the streams. The results are compared with published data on the productivity of protozoa in other habitats and of other invertebrates within the chalk stream ecosystem. The limitations of such productivity estimates are discussed.  相似文献   

17.
Many ant species accumulate organic debris in the vicinity of their nests. These organic materials should provide a rich resource base for the soil biota. We examined the effect of harvester ant nests (Pogonomyrmex barbatus) on the soil community and soil chemistry. Ant nest soils supported 30-fold higher densities of microarthropods and 5-fold higher densities of protozoa than surrounding, control soils. The relative abundances of the major groups of protozoa differed as well: amoebae and ciliates were relatively overrepresented, and flagellates underrepresented, in ant nest versus control soils. Densities of bacteria and fungi were similar in the two soil types. Concentrations of nitrate, ammonium, phosphorus, and potassium were significantly higher in ant nest soils, while concentrations of magnesium, calcium, and water were similar in nest and control soils. Ant nest soils were marginally more acidic than controls. The results demonstrate that P. barbatus nests constitute a significant source of spatial heterogeneity in soil biota and soil chemistry in arid grasslands. Received: 17 March 1997 / Accepted: 10 June 1997  相似文献   

18.
Abstract

Tungsten (W) mining has taken place in Ganzhou in China for about 100 years. Such long-term W mining may release large amount of metals to soils and waters around these mines. Twenty soil samples were taken from the area around the W mines and 10 soil samples from an area much farther away. These soil samples were analysed for physicochemical properties, heavy metal content and their chemical forms. Results show that long-term W mining significantly increased both total and labile contents of Cd, Cu, Pb and Zn, but did not, or only slightly, increased the total content of Co, Cr and Ni in the soil near the mine. Average enrichment factor (EF) in the agricultural soils was 4.0, 2.4, 2.2, and 2.0 for Cd, Cu, Pb and Zn, respectively. The labile fraction was dominated by the carbonate-bound fraction for Cd (54.5%) and organic matter-bound fraction for Cu (37.9%), while the major labile fractions for Pb and Zn were associated with carbonates (30.2% and 6.4%), oxides (17.9% and 10.6%) and organic matter (9.2% and 18.8%). Consequently, there is a need to be cautious about Cd in the soils contaminated by W mining.  相似文献   

19.
Abstract Thirty-eight wheat fields in southern England were sampled in an attempt to correlate the amount of take-all disease with 35 microbiological and chemical measurements of soil. There was little correlation between field take-all and pot tests to determine soil infectivity. Myxogastrids were important components of the soil population, being up to half of the amoebal population, and most soils contained dictyostelids, reticulate amoebae and myxobacteria. Amoebae, ciliates, bacteria and saprophytic fungi were recorded for all soils. pH was a major determinant of soil populations, being clearly correlated with fungal abundance and with numbers of ciliates, dictyostelids and bacteria. Principal component analysis separated dictyostelids from the other soil amoebae and again showed the importance of pH in determining soil microbial populations. Take-all was negatively correlated with soil fertility and positively related to nematodes and myxobacteria, but this was probably an effect of take-all, and represented saprophytic growth on dead roots rather than being a cause. Reticulate amoebae and dictyostelids were both correlated with low levels of take-all. This study emphasises the large number of interrelated populations of soil microorganisms which could have an effect on the severity of take-all infections.  相似文献   

20.
Plants growing on metalliferous soils from abandoned mines are unique because of their ability to cope with high metal levels in soil. In this study, we characterized plants and soils from an abandoned Pb-Zn mine in the Basque Country (northern Spain). Soil in this area proved to be deficient in major macronutrients and to contain toxic levels of Cd, Pb, and Zn. Spontaneously growing native plants (belonging to 31 species, 28 genera, and 15 families) were botanically identified. Plant shoots and rhizosphere soil were sampled at several sites in the mine, and analyzed for Pb, Zn and Cd concentration. Zinc showed the highest concentrations in shoots, followed by Pb and Cd. Highest Zn concentrations in shoots were found in the Zn-Cd hyperaccumulator Thlaspi caerulescens (mean = 18,254 mg Zn kg(-1) DW). Different metal tolerance and accumulation patterns were observed among the studied plant species, thus offering a wide germplasm assortment for the suitable selection of phytoremediation technologies. This study highlights the importance of preserving metalliferous environments as they shelter a unique and highly valuable metallicolous biodiversity.  相似文献   

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