潮上带斑节对虾高产养殖试验     

吴序运 《广东海洋大学学报》1995,(1)

１９９０年在潮上带３ｍ的大梅沙养殖场选２８口共１０９００２．４ｍ２虾池进行斑节对虾高产养殖试验。采用提水式供水、虾池小型化、投苗高密度，配备增氧机，精心管养。试验结果获得总产６９５７７．３ｋｇ，平均０．６４ｋｇ／ｍ２，最高１．０１ｋｇ／ｍ２。潮上带提水式高密度精养斑节对虾，具备条件是确实可行的。  相似文献   

Spatiotemporal changes in agricultural land cover in Nepal over the last 100 years   总被引：2，自引：0，他引：2  

Basanta Paudel  Yili Zhang  Shicheng Li  Linshan Liu 《地理学报(英文版)》2018,28(10):1519-1537

In order to advance land use and land cover change (LUCC) research in Nepal, it is essential to reconstruct both the spatiotemporal distribution of agricultural land cover as well as scenarios that can explain these changes at the national and regional levels. Because of rapid population growth, the status of agricultural land in Nepal has changed markedly over the last 100 years. Historical data is used in this study, encompassing soils, populations, climatic variables, and topography. Data were revised to a series of 30 m grid cells utilized for agricultural land suitability and allocation models and were analyzed using a suite of advanced geographical tools. Our reconstructions for the spatiotemporal distribution of agricultural land in Nepal reveal an increasing trend between 1910 and 2010 (from 151.2 × 10² km² to 438.8 × 10² km²). This expanded rate of increase in agricultural land has varied between different eco, physiographic, and altitudinal regions of the country, significantly driven by population changes and policies over the period of this investigation. The historical dataset presented in this paper fills an existing gap in studies of agricultural land change and can be applied to other carbon cycle and climate modeling studies, as well as to impact assessments of agricultural land change in Nepal.  相似文献   

Experimental research on the influence of two cultivation practices on rainfall runoff- and （sandy and muddy） sediment-generating processes in purple soil environment     

XU Pei  ;WANG Yukuan  ;FU Bin 《中国地球化学学报》2008,27(4):370-376

Rainfall simulations have been conducted to study the soil erosion process of purple soil in two cultivation practices---contour cultivation and downslope cultivation. Results showed that under the two cultivation practices, the surface runoff can be described by the logarithmic function formula. In the initial period of rainfall, the amount of runoff increased with the rainfall duration and 20 minutes later it became relatively constant. The changing process of soil erosion rate may be described by the logarithmic function formula. The erosion rate increased with the rainfall duration and 20 minutes later it also became constant. Under downslope cultivation condition, the soil erosion rate increased more significantly than that under contour cultivation condition in the case of gentle rainfall intensity, and there is no obvious difference in erosion rate for downslope cultivation and contour cultivation practices. However, with increasing rainfall intensity the soil erosion rate under the downslope cultivation condition could be more than 30 times that under the contour cultivation condition. But this kind of difference would be reduced to some extent in the case of heavy rain.  相似文献   

高密度电阻率影象系统在地质构造勘测中的应用     

张寿德 《吉林地质》2008,27(1)

论述了新型高密度电阻率影象系统在地质构造勘测中的应用,并通过实例阐述了该系统在隧道勘查中的应用效果。高密度电阻率影象法作为一种无损、快速的探测手段,应该在地质构造特别是隧道勘查中进行推广应用。  相似文献   

The infaunal community in experimentally seeded low and high density Manila clam (Tapes philippinarum) beds in a Po River Delta lagoon (Italy)     

Mantovani  S.; Castaldelli  G.; Rossi  R.; Fano  E.A. 《ICES Journal of Marine Science》2006,63(5):860-866

  相似文献   

热带地区钝顶螺旋藻的大量培养   总被引：4，自引：0，他引：4  

吴伯堂  林坚士  向文洲  曾呈奎 《海洋与湖沼》1992,23(6):663-668

于1989年6月—1990年6月,运用开放式半连续培养的方法在海南省三亚市鹿回头海滩建113m~2养殖池,进行海水螺旋藻大量培养试验研究。结果表明:①海水螺旋藻藻种SCS品系(1984年引进非洲乍得湖Spirulina platensis经分离选育,驯化为海水螺旋藻藻种SCS品系)适宜在热带地区进行大量培养;②用海水培养螺旋藻不需调pH值;③循环使用培养液可以节约肥料和药品,是降低成本的途径之一;④海南省海岸线长,南部气温高,日照充足,在那里生产海水螺旋藻产量高[12.01g/(m~2·d)]、质量好(粗蛋白含量67.28％)。以上几点说明海南省南部滩涂可以大规模生产海水螺旋藻。  相似文献   

大型海藻对富营养化海水养殖区生物修复的研究与展望   总被引：23，自引：4，他引：23  

杨宇峰  费修绠 《中国海洋大学学报(自然科学版)》2003,33(1):53-57

当前 ,中国的多数海水养殖区富营养化相当严重。富营养化可引发赤潮和养殖动物病害 ,给养殖业带来巨大损失。海带、龙须菜、条斑紫菜等大型海藻 ,生产力很高 ,在生长过程中可大量吸收 C,N,P等生源要素 ,在水生态系统碳循环和减缓富营养化方面有很重要的作用。此外 ,海藻产品可食用、作为饲料、工业原料和有机肥料 ,是具有较高价值的商品。大规模栽培大型海藻是减轻养殖区富营养化的有效途径之一。  相似文献   

融合微藻Tetraselmis sp.-1兼养培养条件下的动力学研究     

沈继红  林学政  李光友  刘发义 《海洋科学进展》2003,21(2):226-231

利用统计分析系统(Statistic Analysis System,SAS),对融合微藻Tetraselmis sp.-1兼养培养进行研究,建立了兼养条件下的细胞生长、底物消耗和产物生成3种动力学模型.经过数据验证,3种模型均能较好的反映微藻培养过程.  相似文献   

山东省海水鱼类增养殖业现状及其可持续发展的探讨     

刘世禄  王波 《海洋科学进展》2002,20(1):78-85

介绍了适宜山东沿海鱼类增养殖的主要种类 ,回顾了山东省主要海水鱼类增养殖种类研究和生产发展的历史、山东省近年海水鱼类养殖概况。最后论述了今后的发展战略与对策  相似文献   

SEAWEED CULTIVATION: TRADITIONAL WAY AND ITS REFORMATION   总被引：4，自引：0，他引：4  

费修绠  鲍鹰  卢山 《中国海洋湖沼学报》1999,17(3):193-199

INTRODUCTIONSeaweedcultivationisthemosteffectivewayforobtaininglargeamountofseaweedproducts.Thoughseaweedcultivationhasahistoryofonlyafewdecades,itsdevelopmentisfast (Fei,1 996) .Thetotalproductionofcultivatedseaweedatpresentisabout 62 50× 1 0 3tonsfreshweight,ofwhichLaminariaaccountsfor 3 1 0 0× 1 0 3tons,Undaria 2 2 0 0x 1 0 3tons,Porphyra 750× 1 0 3tons,Gracilariasp .1 0 0× 1 0 3tons,EucheumaandKappaphycus 1 0 0× 1 0 3tons,otherkindofseaweeds 1 0 0× 1 0 3tons.Theestimatedtotal…  相似文献