期刊文献+
共找到6篇文章
< 1 >
每页显示 20 50 100
Distribution and number change of the Littorinid (Gastropoda) on intertidal hard bed in the Jiulong Estuary, Fujian Province
1
《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第2期293-302,共10页
-Among four species of Littorinid, Littorina scabra, L. brevicula, Nodiliitorina millegrana and N. pyramidalis pyramidalis, on the hard intertidal zone in the Jiulong Estuary, Fujian, L. scabra has the most extensive ... -Among four species of Littorinid, Littorina scabra, L. brevicula, Nodiliitorina millegrana and N. pyramidalis pyramidalis, on the hard intertidal zone in the Jiulong Estuary, Fujian, L. scabra has the most extensive distribution both vertically and horizontally, and the highest anual average density. The uppermost limit of vertical distribution of N. pyramidalis pyramidalis is higher than the other three Littorinid. Desiccation is a main factor affecting the uppermost limit of vertical distribution of the Littorinid. The increasing wave action will raise the uppermost limit vertical distribution of Littorinid. With seasonal changes, the densities of the Littorinid also change in different tidal zonations. Difference in salinity is the main factor affecting the horizontal distribution of the Littorinid in the estuary. 展开更多
关键词 Li on intertidal hard bed in the Jiulong Estuary Distribution and number change of the Littorinid
下载PDF
Distribution and number change of the Littorinidae (Gastropoda) on intertidal hard bed in the Jiulong River Estuary
2
作者 Yi Jiansheng and Li FuxueDepartment of Oceanography, Xiamen University, Xiamen, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1989年第1期160-160,共1页
There are 4 species of Littorinidae on the intertidal hard bed in the Jiulong River Estu-ary. They are Littorina scabra, L. brevicula, Nodilittorina pyramidalis pyramidalis and N.millegrana. Of these species, L. scabr... There are 4 species of Littorinidae on the intertidal hard bed in the Jiulong River Estu-ary. They are Littorina scabra, L. brevicula, Nodilittorina pyramidalis pyramidalis and N.millegrana. Of these species, L. scabra is a dominant species. According to the results of in-vestigation, we find distribution patterns of the Littorinidae on intertidal hard bed in theestuary as follows: (1)There is no Littorinid species at Haicheng Station. (2)There is only Lit- 展开更多
关键词 GASTROPODA Distribution and number change of the Littorinidae on intertidal hard bed in the Jiulong River Estuary
下载PDF
Annual change of the number of anaerobic sulf ite reducing bacteria in sediment of the Daya Bay
3
作者 Zhou Zongcheng, Ni Chunzhi, Zeng Huoshui, Yao Ruimei, Cai Ziping, Lin Yanshun, Liang Ziyuan and Gu Jingyu Third Institute of Oceanography, State Oceanic Administration, Xiamen 361005, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第3期441-447,共7页
The surface sediment samples were collected month by month at nine stations in the Daya Bay from January to December 1987, and the number of anaerobic sulfite reducing bacteria and their spores and the regularity of s... The surface sediment samples were collected month by month at nine stations in the Daya Bay from January to December 1987, and the number of anaerobic sulfite reducing bacteria and their spores and the regularity of seasonal change were determined. The effect of environmental factors, water temperature and the resoluble oxygen concentration in the bottom of seawater on the number of them were discussed. The results show that the number of anaerobic su|fite reducing bacteria were low in sediment of the Daya Bay, indicating that the hay was less contaminated. 展开更多
关键词 Annual change of the number of anaerobic sulf ite reducing bacteria in sediment of the Daya Bay
下载PDF
The temporal and spatial patterns of terrestrial net primary productivity in China 被引量:14
4
作者 TAOBo LIKerang +1 位作者 SHAOXuemei CAOMingkui 《Journal of Geographical Sciences》 SCIE CSCD 2003年第2期163-171,共9页
In this paper, we use CEVSA, a process-based model, which has been validated on regional and global scales, to explore the temporal and spatial patterns of Net Primary Productivity (NPP) a... In this paper, we use CEVSA, a process-based model, which has been validated on regional and global scales, to explore the temporal and spatial patterns of Net Primary Productivity (NPP) and its responses to interannual climate fluctuations in China's terrestrial ecosystems over the period 1981-1998. The estimated results suggest that, in this study period, the averaged annual total NPP is about 3.09 Gt C/yr -1 and average NPP is about 342 g C/m 2 . The results also showed that the precipitation was the key factor determining the spatial distribution and temporal trends of NPP. Temporally, the total NPP exhibited a slowly increasing trend. In some ENSO years (e.g. 1982, 1986, 1997) NPP decreased clearly compared to the previous year, but the relationship between ENSO and NPP is complex due to the integrated effects of monsoons and regional differentiation. Spatially, the relatively high NPP occurred at the middle high latitudes, the low latitudes and the lower appeared at the middle latitudes. On national scale, precipitation is the key control factor on NPP variations and there exists a weak correlation between NPP and temperature, but regional responses are greatly different. 展开更多
关键词 China terrestrial ecosystem NPP CEVSA interannual variation climate change CLC number:Q948 X171.1
下载PDF
Twenty years of Chinese vascular plant novelties,2000 through 2019 被引量:33
5
作者 Cheng Du Shuai Liao +1 位作者 David E.Boufford Jinshuang Ma 《Plant Diversity》 SCIE CAS CSCD 2020年第5期393-398,共6页
From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).During those 20 yea... From 2000 to 2019,11,895 new names or new additions to the Chinese vascular flora were proposed by 4226 individuals(4086 articles and 140 books),as documented in the Chinese Plant Names Index(CPNI).During those 20 years,4407 new taxa of vascular plants were described from China,including 7 new families,132 new genera,3543 new species,68 new subspecies,497 new varieties and 160 new forms.Additionally,3562 new combinations and names at new rank and 306 new replacement names were also proposed.Among these various new names were 150 invalid names and 108 illegitimate names,including some that have not been resolved.Six hundred and forty three vascular plants were reported as new to China,while 2349 names were reduced to synonyms of 1406 taxa.The data show that the Chinese flora increased in size at the rate of about 200 taxa annually during those years.Despite the increased attention given to biodiversity in recent years,the evidence indicates that a large number of species in China have yet to be discovered.Further basic investigation of the Chinese flora is needed.Additionally,in the past two decades only 8.5%of the newly published species have been based on molecular evidence,but in the past five years such data have increased significantly,reaching about 20%.Molecular data will undoubtedly become increasingly significant in the discovery of new species in the coming years.Yunnan,Guangxi,Sichuan,Xizang and Taiwan were important sources of new discoveries,with more than 3300 new taxa and records from these five provinces.By area,Taiwan and Hainan,two islands in southern China,have the highest density of newly discovered species.Regional plant surveys are still needed,especially in areas in the southwest and on the southern islands. 展开更多
关键词 Novelties of Chinese vascular plants number of new taxa number of new name changes Authors of new taxa
下载PDF
SIMULATION OF INVENTORY POLICY FOR PRODUCT WITH PRICE AND TIME-DEPENDENT DEMAND FOR DETERIORATING ITEM
6
作者 D.SHUKLA U.K.KHEDLEKAR +1 位作者 R.P.S.CHANDEL S.BHAGWAT 《International Journal of Modeling, Simulation, and Scientific Computing》 EI 2012年第1期1-30,共30页
In a declining market for goods,we optimize the net profit in business when inventory management allows change in the selling prices n times over time horizon.We are computing optimal number of changes in prices,respe... In a declining market for goods,we optimize the net profit in business when inventory management allows change in the selling prices n times over time horizon.We are computing optimal number of changes in prices,respective optimal prices,and optimal profit in each of the cycle for a deteriorating product.This paper theoretically proves that for any business setup there exists an optimal number of price settings for obtaining maximum profit.Theoretical results are supported by numerical examples for different setups(data set)and it is found that for every setup the dynamic pricing policy out-performs the static pricing policy.In our model,the deterioration factor has been taken into consideration.The deteriorated units are determined by the recurrence method.Also we studied the effect of different parameters on optimal policy with simulation.For managerial purposes,we have provided some“suggested intervals”for choosing parameters depending upon initial demand,which help to predict the best prices and arrival of customers(demand). 展开更多
关键词 Dynamic pricing DETERIORATION time-dependent price sensitive demand optimal policy optimal number of change in price
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部