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1.
有机-无机土壤改良剂对滨海盐渍土降盐防碱的效果   总被引:2,自引:0,他引:2  
以脱硫石膏为主要材料添加天然有机类物质制成的土壤改良剂,在碱性淡水淋盐过程中应用达到盐渍化土壤迅速脱盐防止碱化的效果.盆栽试验采取3因素3水平组合设计,2种质地土壤,3个灌水量,3个改良剂施用量,3次重复,以不施改良处理为对照,试验作物为油菜(Brassica campestris L.)"傲绿101".结果表明:灌水淋洗可以使盐渍化土壤迅速脱盐,灌水量525 m3·hm2、750 m3·hm-22种质地土壤全盐量分别由0.34%和0.54%下降至0.15%~0.309%和0.16%~0.38%.施用改良剂能够改变土壤盐分组成,降低土壤碱化度,与对照相比,土壤ESP和交换性Na+分别下降25.02%~64.86%和23.95%~57.83%.土壤HCO3-、Cl-与改良剂施用量呈负相关,土壤SO42-、Ca2+与改良剂施用量呈正相关.综合结果分析,重壤质土壤灌水量525 m3·hm2与改良剂施用量1 500 kg·hm-2组合、灌水量750 kg·hm3与改良剂施用量1 500kg·hm-2组合;中壤质土壤灌水量525m3·hm-2与改良剂施用量3 000 kg·hm-2七组合为首选.  相似文献   

2.
土壤改良剂对沙生灌木生理生态因子的影响研究   总被引:1,自引:0,他引:1  
为了探讨自制土壤改良剂施用于沙质土壤后对沙生灌木生理生态因子的影响效果,通过正交设计、盆栽试验比较了不同改良剂及不同施用量下3种沙生灌木杨柴(Hedysarum mongolicum Turez)、柠条(Caragana Korshinskii Kom.)和沙柳(Salixpsammophila)生理生态因子的变化特征,在分析改良剂作用机理基础上,筛选出适宜的改良剂及其使用量。研究结果表明,自制土壤改良剂能显著提高植株叶片光合速率、降低高温胁迫下的蒸腾速率,提高叶水势。通过方差分析,添加自制改良剂300 g(占土壤基质的质量分数为6%)对提高柠条的光合速率效果最佳;添加自制改良剂150 g(占土壤基质的质量分数3%)对降低沙柳的蒸腾速率效果最明显;添加自制改良剂300 g(占土壤基质的质量分数6%)对提高沙柳叶水势的效果最显著。另外,应用最小隶属度偏差法进行综合评价得出:添加自制改良剂300 g(占土壤基质的质量分数6%)在改良柠条植物生理特性方面的效果最佳。  相似文献   

3.
陈琼贤  彭志平 《生态环境》2002,11(4):373-375
探讨了营养型土壤改良剂(简称改良剂)对水稻产量、土壤酸度、土壤养分、土壤肥力和土壤物理性能的效应。连续2年4造水稻试验结果表明,施用改良剂比对照稻谷产量增加8.6%~11.3%(平均10.3%),增产达极显著水平,并且有良好后效。施用土壤改良剂具有提高pH,降低活性Al,增加N、P、K有效养分和代换性K、Ca和Mg的效果。  相似文献   

4.
通过盆栽试验,对土壤采用添加25%土壤改良剂、以及添加12.5%改良剂和12.5%腐殖质的2种处理方式,研究Arkadolith土壤改良剂对冰草(Agropyron desertorum)、沙打旺(Astragalus huangheensis)和准格尔苜蓿(Medicago sativa cv "Zhonggeer")3种沙生牧草的生长特性的影响。结果表明,3种牧草中,植株高度、生长力、发芽力以及产量都较土壤改良前有所增强,沙打旺和准格尔苜蓿的生长状况要明显好于冰草。含有多种矿物成分的Arkadolith土壤改良剂不仅可以改良贫瘠土壤,提高土壤肥力,促进牧草的增产,而且还可以减少化学肥料的施用,降低成本,做到绿色环保,因此其具有广泛的推广意义。  相似文献   

5.
采用定位研究方法,以中亚热带区域七种典型森林生态系统为研究对象,探讨了不同生态系统对土壤生物学肥力指数、内梅罗土壤质量指数、土壤退化指数的影响,以及各指数之间的相互关系.结果表明,土壤生物学肥力指数和内梅罗土壤质量指数都是以常绿阔叶林最高,其次是混交林和阔叶纯林,连栽杉木纯林最低.土壤退化指数与内梅罗土壤质量指数正好相反,连栽杉木纯林土壤退化指数最高,混交林和阔叶纯林稍低.另外,混交树种不同,土壤质量指数也有差异.相关分析表明,内梅罗土壤质量指数、土壤退化指数与土壤生物学肥力指数相互之间存在正的相关性;另外,这3种土壤质量指示指标分别和林下植被层、森林凋落物现存量之间也有着显著的正相关.  相似文献   

6.
我国西南喀斯特生态脆弱区以土壤退化为核心的环境退化形势严峻.揭示土壤退化过程和退化机理,是认识喀斯特这个特殊环境的土地生态系统诸多环境退化问题的一个重要途径.本文选择黔中猫跳河流域上游长顺县广顺乡典型喀斯特景观为研究区,通过野外采样和实验室分析,对不同土地利用类型的土壤水分性能进行了比较研究,以探讨喀斯特地区土壤退化的过程与机理.结果表明,与基本无退化的本底林地相比较,草地土壤的水分性能明显变劣,表现为:土壤的持水能力下降,田间持水量和毛管持水量分别下降49.5%和56.2%;土壤供水能力降低,总有效含水量下降56.4%;土壤渗透性能减弱,150 min饱和渗水量减少70.1%.土壤的这些水分特征与土壤发生的强度和速度都有着非常密切的关系,草地土壤水分性能的这种退化将加剧土壤的侵蚀.可以认为,在西南典型喀斯特地区,土壤的水分退化是土壤退化的一个关键过程和因素.  相似文献   

7.
土壤侵蚀退化研究进展   总被引:3,自引:0,他引:3  
从土壤物理退化、化学退化和生物学退化等3个方面回顾了国内外的土壤退化过程研究的历史与现状,全面总结了国内外在土壤侵蚀退化形成的过程、机理、影响因素以及评价土壤退化的指标方法等方面的最新研究进展,最后提出了土壤退化过程和防治方法研究中存在的主要问题,并从多学科交叉的角度和土壤侵蚀退化机理研究及定量动态监测角度来展望土壤侵蚀退化研究的进一步发展方向。  相似文献   

8.
彭桂香  蔡婧  林初夏 《生态环境》2005,14(5):654-657
通过盆栽试验,观察分析不同的土壤改良配方对重金属超积累植物东南景天盆栽土壤中细菌、真菌和放线菌数量、Cmic及Nmic的影响,以此来筛选出最优的促进东南景天修复锌镉污染土壤的改良剂配方。结果显示:细菌、真菌和放线菌数量,与土壤Zn、Cd的去除率、东南景天植株干质量、Cmic及Cmic/Nmic两两之间都呈现极显著正相关关系(但Cmic/Nmic与真菌数量仅呈显著相关)。添加了土壤改良剂后,细菌、放线菌、真菌的数量都有不同程度的增加,其中以细菌数量的增加最为显著,放线菌次之,真菌则对各种土壤处理相对较不敏感;在各种土壤配方中,添加了6 g赤泥、15 g污泥和15 g沸石的T7处理最有利于各类土壤微生物的生长,微生物量碳达到345.64 mg.kg-1,与其它处理之间都达到显著差异。因此,可以利用土壤微生物作为污染土壤改良情况的生物指标。该研究为下阶段研究化学改良剂-植物-微生物修复技术奠定了基础。  相似文献   

9.
秸秆还田下改良剂对水稻生长和Cd吸收积累的影响   总被引:4,自引:0,他引:4  
土壤中的镉(Cd)易在水稻中积累而威胁人体健康,秸秆还田下不同化学改良剂对水稻Cd 吸收累积特性的影响效应值得关注.选取成都平原德阳市旌阳区Cd 污染稻田为研究对象,开展小区试验,研究秸秆(油菜、小麦)直接还田下添加石灰、钙镁磷肥、海泡石3 种改良剂对水稻生长和Cd 吸收累积的影响.结果表明:与对照相比,油菜秸秆+钙镁磷肥和小麦秸秆+海泡石处理均能增加水稻株高、分蘖数和产量,其中产量提高了6.34%和12.64%,达显著水平(P〈0.05).秸秆还田下,配施改良剂(石灰、钙镁磷肥、海泡石)均能显著降低(P〈0.05)水稻糙米Cd 含量,较对照降幅分别为21.65%-36.75%(油菜秸秆还田)和21.11%-33.87%(小麦秸秆还田).油菜秸秆+改良剂(石灰、钙镁磷肥、海泡石)促进了土壤Cd 向茎叶的累积,较对照增加1.31-2.41 倍,这对水稻秸秆(茎叶)还田利用有不利影响.小麦秸秆+石灰或海泡石处理均显著降低了茎秆、谷壳Cd 积累,较对照降幅为6.28%-19.63%和70.16%-78.68%.综合水稻产量及其对土壤Cd 吸收累积效应,油菜秸秆配合改良剂(海泡石、石灰和钙镁磷肥)、小麦秸秆+海泡石是较为理想的秸秆还田与改良剂配合处理技术.  相似文献   

10.
综述了近年来海洋微生物来源天然产物研究的新进展,总结了该类天然产物的开发策略.通过对样品采用不同的预处理方式、不同的分离培养基以及新的培养方法,讨论如何获得海洋来源的特有微生物和增加海洋来源微生物类群的多样性.阐述了在海洋微生物天然产物的开发过程中,采用宏基因组技术及基因组测序等手段,来发现难培养或不可培养微生物中的天然产物以及处于"沉默"状态的天然产物.最后介绍了异源生物合成、组合生物合成以及核糖体工程等技术在海洋微生物天然产物开发和改造中的应用,并举例论述了海洋微生物天然产物的开发.  相似文献   

11.
《生态毒理学报》2006,1(1):93-95
<正>王子健,男,1953年10月出生,博士,研究员,博士生导师.1976年中国科技大学毕业后到中科院生态环境研究中心工作.1983-1985年在瑞士留学,从事水质污染化学规律研究;1987年在日本从事生物样品生理活性物质分析方法研究. 1992-2000年担任中科院生态环境研究中心环境水化学国家重点实验室副主任、主任,兼环境模拟与污染控制国家重点联合实验室学术委员会委员,国家863计划污染控制技术主题专家组副组长,国家自然科学基金委员会地球科学部第二届咨询专家委员会委员,国际环境地球化学与健康学会亚太分会理事,全球环境基金专家库成员等.同时担任环境科学学报(副主编)、过程工程学报、环境化学、湿地研究、地球与环境、美国Environmental Science and Health(A)等杂志的编委.王子健领导的研究小组主要研究天然水体和水处理过程中的水质转化、相关毒性和毒理变化以及健康和生态风险.内容包括发展新的环境监测技术,离体和活体生物毒性测试方法,污染物水体多介质过程,水质安全性评价以及水污染的健康和生态风险的指标和方法.在开发新型生物模拟采样技术和生物毒性测试方法体系、生活饮用水和再生水的安全性评价、持久性有毒污染物污染及其生态与健康影响等方面取得了丰硕的成果,相当一部分成果得到推广应用.  相似文献   

12.
目前常用降水量乘以降水入渗补给系数的方法计算降水入渗补给量,此法不能表现降水特征、蒸发等因素对降水入渗补给的影响.为解决不同时间尺度、不同降水特征和蒸发情况下的降水入渗补给量,在分析郑州地下水均衡试验场地中渗透仪实测入渗量、降水和蒸发资料的基础上,利用均匀设计法选取最优的与降水入渗补给量关系密切的前期降水量和蒸发量的期次,然后利用回归分析建立各岩性和埋深的年、月和日尺度上的降水入渗函数,可以比较准确的计算降水入渗补给量.表3,参9.  相似文献   

13.
利用过滤的天然珍珠养殖水参照BG11配制加富培养液,将1株能促进鱼害微囊藻生长的微小杆菌属菌株(Exiguobacterium sp.013,简写为E.sp.013)进行纯化扩大培养后与铜绿微囊藻(Microcystis aeruginosa)、水华微囊藻(Microcystis flosaquae)、平裂藻(Merismopedia sp.)和惠氏微囊藻(Microcystis wesenbergii)按一定菌、藻密度比例同时接种后进行为期24 d的培养试验,利用特定生长率和细胞密度等指标观察并检验E.sp.013菌株对4种蓝藻生长的影响,同时检测培养液中优势菌群的数量变化趋势.结果表明:E.sp.013菌对铜绿微囊藻、水华微囊藻和惠氏微囊藻具有显著促生长和延长稳定生长期作用,对平裂藻不具有显著促生长作用,但对延长其稳定生长期具有显著效果;试验培养过程中E.sp.013菌落数量占所有菌落总数的比例始终高于46%,处于绝对优势地位,表明E.sp.013菌具有调控其他菌群的能力.  相似文献   

14.
The induction of metamorphosis in mature larvae by selected chemical compounds and natural substrata was investigated in two species of sea urchins from the Sea of Japan, Strongylocentrotus intermedius and Scaphechinus mirabilis. Glutamine in crystalline form was added directly to water containing mature larvae, and this compound, at a final concentration of 10 g ml-1, was an inducer of metamorphosis in S. intermedius (100% activity) and S. mirabilis (50% activity). Gutamine, or its natural mimetic molecules, may be an active component of the exogenous cue that induces metamorphosis of S. intermedius larvae. This exogenous cue was produced by the epiphytic calcareous algae, Melobesia spp. that colonized the older sea grass Zostera marina. Glutamic acid was also used as an inducer of metamorphosis for S. intermedius and S. mirabilis larvae (50 to 60% activity), but it was toxic to the larvae.  相似文献   

15.
南京城市西部历史时期是城市的重要边界,现在逐渐演变成老城与新区之间的核心地带,成为公共活动的重要地区,保护其自然、文化遗产和生态环境具有非常重要的意义。在对其现状调查分析的基础上,梳理遗产点的历史概况、现状及其分布情况,提出规划遗产廊道的意义,探讨规划的具体思路,为南京遗产保护提供了新的视角。  相似文献   

16.
17.
Adsorption potential of a commercial activated carbon (FS300) has been evaluated for the uptake of cationic dyes namely methylene blue (MB) and rhodamine B (RB). Though, there are numerous studies in literature which report the sorption of MB (more than 40 studies) and RB (more than 10), however none of these use a common parameter to report the capacity of the sorbent. A protocol, based on the equilibrium dye concentration has been proposed to measure the sorption potential of a sorbent. The Langmuir model can very well describe the experimental equilibrium data for both dyes (coefficient of correlation > 0.999). MB (Qm = 312.5 mg g(-1)) is more adsorbable than the RB (Qm = 144.9 mg g(-1)). Molecular weight and chemical structure of dye molecules seem to affect the dye uptake. The effect of pH on dye uptake has also been evaluated by varyingpH from 3 to 11. Uptake of MB increases with pH, wherein RB removal decreases with pH. Dyes could not be desorbed either by distilled water (0.06 and 0.11% for MB and RB respectively), or by 0.1 NHCl (0.136 and 3.0% for MB and RB respectively) indicating, chemical adsorption type of adsorbent-adsorbate interactions.  相似文献   

18.
M. G. Hoskin 《Marine Biology》1997,127(4):647-656
 In south-eastern Australia, the prosobranch gastropods Morula marginalba (Blainville), Cominella lineolata (Lamarck) and Bedeva hanleyi (Angas) have similar fine-scale distributions, but appear to possess very different dispersal capabilities due to contrasting modes of larval development. M.marginalba produce planktonic larvae, whereas C. lineolata and B. hanleyi undergo direct development in benthic egg capsules and emerge as crawling juveniles. To test for possible effects of contrasting life histories on levels of genetic variation within and among populations, a survey was conducted of allozyme variation at six polymorphic loci in 8 to 9 local populations of each species. Collections of snails were made between June 1992 and November 1993. Sampling ranges spanned between 162 and 180 km of coast. Regardless of larval type, proportions of single-locus genotypes in each collection were consistent with the recruitment of offspring which had been generated through random mating. However, genotypic diversity was lower in those species that undergo direct development. Loci surveyed in C. lineolata and B. hanleyi were polymorphic (i.e. frequency of most common allele <95%) in fewer populations than those examined for M.␣marginalba (P <0.001) and, where polymorphisms occurred, also possessed significantly fewer alleles (P <0.001). Consequently, average levels of expected heterozygosity were greater in populations of M. marginalba than in those of either of the other species (P <0.001). Genetic variation among populations, expressed as the standardised variance in allele frequencies (F ST ), was inversely related to expected larval dispersal capability. The nine collections of M. marginalba showed little overall differentiation (F ST  = 0.017; P <0.001), reflecting the ability of planktonic larvae to interconnect local populations, and so limit divergence due to drift and natural selection. In contrast, there were high levels of allelic heterogeneity among the nine collections of C. lineolata (F ST  = 0.523; P <0.001) and eight collections of B. hanleyi (F ST  = 0.140; P <0.001). These data imply that for species which undergo direct development, local populations are effectively closed and evolve largely independent of one another. Received: 3 May 1996 / Accepted: 12 July 1996  相似文献   

19.
The pattern of settlement over time of three broadcast spawning coral species (Cyphastrea serailia, Acanthastrea lordhowensis, and Goniastrea australensis) from the Solitary Islands (30°00′S; 153°20′E) was studied in 1995 and 1996 in order to determine the maximum length of time these larvae could remain in the water column and still retain the ability to settle and metamorphose. Larvae were maintained in aquaria and the number which had settled on biologically-conditioned tile pairs was monitored every 5 to 10 d. While the majority of larvae settled quickly after becoming competent, some larvae survived and settled for extended periods after spawning. Competency periods ranged from 26 d for C. serailia to 56 d for G. australensis and 78 d for A. lordhowensis. These data greatly extend the known competency periods for larvae of broadcast-spawning corals and indicate the potential for transport of broadcast-spawned coral larvae over large distances. Medium to long-distance larval dispersal of the species studied provides a mechanism for their widespread distribution in subtropical regions, on reefs which are often widely spaced and relatively isolated. Received: 27 May 1997 / Accepted: 27 November 1997  相似文献   

20.
不同饲粮对生猪产污情况的影响   总被引:2,自引:0,他引:2  
研究了精饲料和精青配合饲料饲养下育肥猪排污量和主要污染物含量的差异.结果表明,与饲喂精饲料相比,饲喂精青配合饲料的生猪产粪量降低18.97%,产尿量降低38.56%.精饲料饲养50d后,生猪体质量仅比精青配合饲料饲养平均增加1.5kg,采用精青配合饲料饲养的生猪体质量每增加lkg饲料成本投入比精饲料饲养减少21.68%.精青配合饲料喂养生猪不仅可减少污染物的排放量,还可节约饲料投入成本,提高养猪效益.  相似文献   

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