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1.
以缢蛏为主的生态综合养殖池塘氮磷流转研究   总被引:1,自引:0,他引:1  
养殖池塘生态系统氮(N)、磷(P)的流转及N、P利用率情况常作为评价池塘养殖模式及其水平的重要指标.以缢蛏(Sinonovacula constrzcta)为主的生态综合养殖池塘为研究对象,于2011年4—11月期间每月测定一个水交换周期内池塘的进排水总磷(TP)、总氮(TN)、叶绿素a(Chl a),根据养殖记录估算以肥料、饲料和养殖动物苗种输入的N、P含量及养殖动物生长积累的N、P含量,评估以缢蛏为主的生态综合养殖池塘N、P流转情况.结果表明:在输入的N中化肥输入比例最高,约占57.0%;水动力交换输入约占12.9%;饲料输入约占24.0%.在输入的P中最主要的输入是化肥和饲料输入,分别为69.3%和16.9%;水交换输入约为11.6%;罗非鱼(Oreochromis niloticus)苗输入1.1%.在N的输出中,最主要的是水动力交换输出,约占66.0%,被收获养殖动物利用的N约为29.6%,其中罗非鱼14.3%,缢蛏11.5%,对虾3.8%.在P的输出中,水动力交换输出约为69.1%,被收获养殖动物利用的P为22.2%,其中罗非鱼占13.4%,缢蛏占7.8%.约有4.5%的N和约8.7%的P通过渗漏或沉积,形成内源污染.  相似文献   

2.
珠三角养殖池塘水质模型建立及其应用研究   总被引:4,自引:0,他引:4  
 以珠江三角洲的基塘式精养池塘为例,经过参数率定、模型验证等工作,建立了地方性精养池塘的水质模型。模型的验证结果表明模型的模拟基本上重现了养殖生产活动过程中生态系统的变化趋势,可以为养殖池塘生态系统的研究和辅助地方的养殖管理工作提供一定的参考。利用建立的养殖池塘的水质模型研究了养殖池塘的水质影响因子和养殖容量的影响因素,研究结果表明:高密度精养池塘氧气的平衡机制已发生了较大的变化,鱼类呼吸已成为耗氧的主要组分,人工增氧的作用已接近甚至超过藻类产氧作用。溶氧浓度易受到各种机制的影响而发生较大的变化。养殖池塘NH + 4-N、PO 3- 4的主要来源是鱼类代谢,主要消耗是藻类吸收,二者在水中稳定性好。养殖池塘的养殖容量受到许多因素的影响,内因有饵料的可消化率和可利用率,外因有溶氧水平和NH+4-N的累积等。在精养池塘,随着饵料消化率提高,主养鱼容量迅速增长,最终受制于DO的不足和NH + 4-N的累积,套养鱼容量随着主养鱼类的饵料利用率降低而增加,最后受制于DO的不足。如果采用轮放,轮捕的养殖方式,将会更充分的利用养殖空间,进一步扩大养殖容量。  相似文献   

3.
通过使用沉积物捕获器获取沉积物,研究了一生态综合养殖池塘的沉积作用,并利用室内模拟实验研究了缢蛏(Sinonovacula constrzcta)的生物沉积作用,同时分析了池塘沉积物及其间隙水的营养盐;应用Fick第一定律对池塘沉积物-池水界面营养盐通量进行了估算.藻类池颗粒物质的日平均沉积速率为44.59 g/m2,贝类池颗粒物质的日平均沉积速率为14.01 g/m2;两个池塘试验期内(90 d)N、P的净沉积量分别为6061.5 g和3411 g(采样池塘面积各0.5 hm2,水深50~60 cm).结果显示实验期内生态综合养殖池塘沉积作用分别占N、P营养元素输出的2.2%和5.8%(质量分数).  相似文献   

4.
研究了海水围塘混合养殖生态系统的氮磷循环,建立了N、P物质平衡方程.结果 表明:海水围塘混合养殖中N的利用率较虾池等精养封闭系统要低,而P的利用率则与之持平;海水围塘混养中N、P的输入主要来源是投饵和肥料,除了10%左右被利用收获外,其余的大部分被换水、渗漏排出,污染附近海域,另有部分沉积在底泥中,形成内源污染.  相似文献   

5.
以不同浓度的畜禽养殖废水为对象,研究藻菌体系对废水中的NH4+-N、TP和COD的去除效果。结果表明:藻菌体系对不同浓度的畜禽养殖废水的处理效果不同,当废水中NH4+-N、TP和COD浓度分别小于44.4 mg/L、6.4 mg/L和500 mg/L时,藻菌微生物的生长速度快、生物量大,对废水处理效果好;当处理时间为6 d时,NH4+-N、TP和COD的去除率分别大于90%、84%和80%,该实验结果为构建高效藻类塘提供理论依据。  相似文献   

6.
该文通过自然条件下菊花心江蓠对排海污水的生物净化实验,研究了菊花心江蓠对N、P等的吸收规律.实验前3d,菊花心江蓠迅速吸收水体中NH4-N.当介质中NH4-N浓度低于0.01mg.L-1时,NO3-N浓度迅速降低.实验过程中,菊花心江蓠对TP吸收较为缓慢,经过11d修复,Ⅰ~Ⅵ各组TP降解率分别为67.90%、90.01%、95.63%、84.16%、91.75%、93.61%.  相似文献   

7.
本研究以海水池塘养殖园区排放水集中设施化处理为切入点,集成泡沫分离、生物滤池及大型藻等多种生态修复技术,构建了海水池塘养殖园区排放水综合生态净水系统。经过综合生态净水系统处理,池塘养殖排放水中化学耗氧量(COD)、氨氮(NH4-N)、亚硝氮(NO2-N)、硝氮(NO3-N)、溶解无机氮(DIN)及活性磷酸盐(DIP)综合去除率平均分别为40.84%、89.37%、86.88%、93.75%、78.74%和59.73%。通过该技术可明显改善园区排放水质量,基本可以实现各项指标的达标排放。  相似文献   

8.
以龙亭湖西湖为研究对象,共采集到23个水体样品和23个沉积物样品,据此分析测定水体和沉积物中TN、TP、NH4.N、NO3.N、NO2.N、PO4等含量,并对N、P各种存在形态进行分析测定.通过对水体和沉积物污染状况。以及沉积物污染对上覆水体水质影响的研究表明:对照地表水国家标准GB-3838-2002氨氮含量标准,龙亭湖水体上覆水集中于1、2、3、4类,其中3类水所占比例最高;沉积物对上覆水体NH4-N、NO3-N起到一定程度的净化作用,却是NO2.N、PO4的储存库,是龙亭湖上覆水体的一个内在污染源.研究结果为龙亭湖水体污染治理提供重要的决策依据.  相似文献   

9.
助剂对石油污染土壤生物修复的强化作用   总被引:1,自引:0,他引:1  
在添加高效降解菌剂的基础上,研究了营养物质的种类、添加量以及不同表面活性剂对石油污染土壤修复效果的影响。结果表明,营养物质种类对修复过程的影响显著,添加N、P含量较高的硝基磷酸铵以及自行配制的NH4NO3:NH4H2PO4=5:1混合肥料的处理石油降解率比对照分别提高15.1%以及17.2%,当土壤中C:N的比例控制在100:7.05~100:9.4之间时,修复效果较好,且肥料的添加宜采用少量多次的原则;添加表面活性剂的处理中,鼠李糖脂的处理效果最好,石油降解率比对照提高8%,优于其他化学表面活性剂处理。  相似文献   

10.
采用动态膜生物反应器(DMBR)处理养殖废水,考察盐度为0~3 000mg·L-1时动态膜生物反应器的脱氮效能.结果表明:DMBR对养殖废水的CODMn和NH3-N的去除效果保持稳定,分别为93%,87%左右;在盐度提高到1 000mg·L-1后,DMBR内反硝化速率明显提高,对NO3-N的去除率提高到97%,总氮去除率也达到94%.在盐度为0~3 000mg·L-1下,DMBR处理养殖废水的出水水质达到SC/T 9101-2007《淡水池塘养殖水排放要求》中的一级排放标准.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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