中国东部沿海地区城市经济韧性的空间差异及其产业结构解释

经济韧性的强弱决定着城市在面对冲击时可以快速度过危机还是陷入长期经济发展停滞。本文将城市经济韧性区分为长期经济韧性和短期经济韧性,分析中国东部沿海地级及以上城市的经济韧性和产业结构的时空分异特征,探讨产业结构在不同时期对城市经济韧性的影响。研究发现,东部沿海地区城市不同时期的短期经济韧性及长期经济韧性存在明显的空间差异;长期经济韧性和短期经济韧性的影响因素不同,表征产业整体技术含量的经济复杂度和表征产业关联程度的相关多样化指数能显著提升城市长期经济韧性,短期经济韧性的影响因素则因时期不同而存在差别。延长产业价值链、构建地方产业集群、提升产业层次水平,有助于城市提高经济韧性。     

榆树地震台地电场观测系统运行评价

详细介绍榆树地震台地电场观测系统的运行状况,从数据完整率、静日、扰日变化形态以及相关系数、差值等方面对观测系统运行进行综合评价,结果表明:榆树地震台地电场观测系统运行稳定可靠,能够记录到震前地电场异常变化,可以为地震预测预报研究提供一定依据。     

High genetic diversity in gametophyte clones of Undaria pinnatifida from Vladivostok, Dalian and Qingdao revealed using microsatellite analysis

Breeding practice for Undaria pinnatifida (Harvey) Suringar requires the screening of a large number of offspring from gametophyte crossings to obtain an elite variety for large-scale cultivation. To better understand the genetic relationships of different gametophyte cultures isolated from different sources, 20 microsatellite loci were screened and 53 gametophyte clone cultures analyzed for U. pinnatifida isolated from wild sporophytes in Vladivostok, Russia and from cultivated sporophytes from Dalian and Qingdao, China. One locus was abandoned because of poor amplification. At the sex-linked locus of Up-AC-2A8, 3 alleles were detected in 25 female gametophyte clones, with sizes ranging from 307 to 316 bp. At other loci, 3 to 7 alleles were detected with an average of 4.5 alleles per locus. The average number of alleles at each locus was 1.3 and 3.7 for Russian and Chinese gametophyte clones, respectively. The average gene diversity for Russian, Chinese, and for the combined total of gametophyte clones was 0.1, 0.4, and 0.5, respectively. Russian gametophyte clones had unique alleles at 7 out of the 19 loci. In cluster analysis, Russian and Chinese gametophyte clones were separated into two different groups according to genetic distance. Overall, high genetic diversity was detected in gametophyte clones isolated from the two countries. These gametophyte cultures were believed to be appropriate parental materials for conducting breeding programs in the future.     

新疆森林资源动态分析

1 M ethod ofsurvey and analysis1.1 Survey area and dataThe survey area am ounted to 1.647 m illion km 2,covering the w hole territory of X injiang.TheLandsat TM im age data obtained from rem ote sensing in w hole X injiang during the periods1995-1996 and …     

黑河流量和祁连山气候的年代际变化

利用黑河上游莺落峡水文站流量资料和选自祁连山区2280～3360m高度处的7个气象观测站平均的历年各月标准化降水量、气温序列,分析了1944～2000年期间黑河流量与祁连山区自然气候的年代际变化。结果表明：20世纪80年代的流量是过去57年中最大的10年,90年代有所减小,但主要表现在夏、秋季,而冬、春季仍然保持高流量。祁连山区气候演变存在非常明显的季节变化、年际变化和年代际变化。自70年代以来,除夏季降水量呈上升趋势外,秋、冬、春三季均表现出明显的变干。尤其是秋、冬两季;自80年代以来,祁连山区气候明显变暖,各季气温显著升高,尤以秋、冬两季升温最快。这可能是冬季黑河流量显著增加,祁连山雪线上升的主要原因。综合分析表明,黑河流量的增加取决于两个方面：一是夏季降水量的增加,二是冬季气候的明显变暖。     

耐盐水稻地方品种的主要性状分析

通过对湛江地区水稻品种的耐盐性、品质性状及主要农艺性状进行分析,结果表明,"咸水禾”品种具有一定的耐盐性,可用1/5海水灌溉,但其耐盐性不高;灌溉水含盐量的高低,对株高和穗粒结构影响较大;3个品种的出糙率均偏低,外观品质较差.并指出增强抗盐性、提高品质应是目前改良耐盐水稻地方品种的主攻方向.     

The Appearance of Ulva laetevirens（Ulvophyceae,Chlorophyta） in the Northeast Coast of the United States of America

Introduced species may outcompete or hybridize with native species, resulting in the loss of native biodiversity or even alteration of ecosystem processes. In this study, we reported an alien distromatic Ulva species, which was found in an embayment（Holly Pond） connected with Long Island Sound, USA. The morphological and anatomical observations in combination with molecular data were used for its identification to species. Anatomy of collected specimens showed that the cell shape in rhizoidal and basal regions was round and the marginal teeth along the basal and median region were not found. These characteristics were primarily identical to the diagnostic characteristics of Ulva laetevirens Areschoug（Chlorophyta）. The plastid-encoding tufA and nucleus-encoding ITS1 were used for its molecular identification. Phylogenetic analysis for the tufA gene placed the specimens from Holly Pond in a well-supported clade along with published sequences of U. laetevirens identified early without any sequence divergence. In ITS tree, the sample also formed well-supported clades with the sequences of U. laetevirens with an estimated sequence divergence among the taxa in these clades as low as 1%. These findings confirmed the morpho-anatomical conclusion. Native to Australia, this species was reported in several countries along the Mediterranean coast after the late of 1990 s. This is the first time that U. laetevirens is found in the northeast coast of United States and the second record for Atlantic North America.     

大容量气枪震源主动探测技术系统及试验研究

针对地下介质动态变化监测研究中的信噪比、震源可重复性和波速精确测量等关键问题,利用大容量气枪震源,构建了一套高性能的主动探测技术系统,该系统包括气枪震源激发和信号接收,并在河北、云南和新疆等地的内陆水库和人工水体等不同激发环境,开展了探索性试验研究。试验结果表明:①气枪震源激发频率低,能量强,具有高度的可重复性、可通过叠加提高信噪比、探测距离大、绿色环保等特征,是一种理想的低频震源;②该探测技术系统操作简单,易控制,自动化程度高,探测精度高,能观测到固体潮引起的连续变化,可应用于区域尺度地下介质动态变化监测和开展4D 地震学研究;③气枪震源激发产生的信号震相丰富,有较强的S波,为研究地壳介质特性、应力分布及其动态变化等提供了新的技术路线。     

Sexual traits plasticity of the potentially invasive limpet Bostrycapulus odites (Gastropoda: Calyptraeidae) within its natural distribution in South America

The slipper limpet Bostrycapulus odites has recently been reported as an introduced species on the Spanish Mediterranean coast. Another species in the family Calyptraeidae, Crepidula fornicata, is a problematic invasive species in the Northeast Atlantic, which makes the closely related Bostrycapulus introduction a matter of concern. Information on the biology of B. odites in its natural environment can facilitate predictions on where the species could find favourable conditions for settlement and expansion. Size and sex were recorded for individuals in four populations over 2600 km of the Southwestern Atlantic shoreline, in Argentina and Brazil, covering the whole native latitudinal range of this widely distributed species. Animals were collected by hand in the intertidal or by SCUBA in subtidal locations; specimens were examined to determine shell length, sex, and the presence and number of brooded egg capsules in females. Mean shell length for the whole population did not differ significantly among populations. However, this species experiences sequential hermaphroditism (protandrism), and the size at sexual maturity (minimum male size) increased significantly with latitude. The fecundity of females at all sites increased with size, and the number of brooded egg capsules as well as the average size of capsules was larger in bigger individual females; however, mean fecundity varied among sites independent of mean female body size. This limpet species modifies its reproductive traits with local conditions, and sexual characters develop earlier in more temperate localities.     

Distribution,population size and conservation of the Cape gannet Morus capensis

The Cape gannet is endemic to the southern African coast where it currently breeds at six islands: Mercury, Ichaboe and Possession off South West Africa and Bird (Lambert's Bay), Malgas and Bird (Algoa Bay) off South Africa. Previously, breeding also occurred at Hollams Bird, Halifax and Seal (False Bay) Islands. Equivocal records for Marcus, Dassen and Dyer Islands are not accepted. Off South West Africa, gannets were breeding at Hollams Bird, Mercury and Ichaboe Islands at least as early as 1828, but they only occupied Halifax and Possession Islands sometime between that date and c. 1885, possibly as a result of displacement of gannets from Ichaboe Island during exploitation of accumulated guano deposits in the early 1840s. Gannets bred at Hollams Bird Island until at least 1938, but had ceased breeding at Halifax Island by 1928. Off South Africa the earliest records of breeding are 1648, 1687, 1755 and 1912 for Malgas, Seal (False Bay), Bird (Port Elizabeth) and Bird (Lambert's Bay) Islands respectively. Gannets have not been reported at Seal Island since the late 17th century. On the west coast of Africa the Cape gannet is a regular nonbreeding winter visitor as far north as 4°20′N 6°00′E, but west of 6°E it is rare. On the east coast of Africa it is a common winter visitor as far north as Delagoa Bay, but farther north it is rare. Within its normal range the Cape gannet seldom occurs farther off shore than 100 km; it hardly ever moves inland. Aerial censuses of Cape gannets at breeding islands in 1967, 1969, 1978, 1980 and 1981 are compared with an aerial census conducted in 1956 and other published estimates of abundance. Between 1956 and 1980 the estimated number of breeding pairs at all colonies decreased from c. 150 000 to c. 80 000 and numbers decreased at all three extant gannetries off South West Africa. These decreases are attributed to a greatly diminished food resource following the collapse of the South West African pilchard stock after the late 1960s. The number of gannets decreased at Bird (Lambert's Bay) and Malgas Islands between 1956 and the late 1960s but subsequently increased, trends that are related to performances of the Western Cape pilchard and anchovy resources respectively. At Bird Island (Algoa Bay) gannets were up to 3,5 times more abundant in the late 1970s than in 1956. Other marine resources located east of Cape Point have shown similar large increases in recent years. Rates of increase of gannets at islands off South Africa during the 1970s would have required an unrealistically high survival for the first year had other population parameters remained constant. It is possible that birds emigrated from the South West African Islands. Few gannets have been reported oiled, and conservation of the species seems to be mainly affected by greatly reduced prey availability and injudicious guano harvesting. Human exploitation of juvenile gannets off the West African coast is difficult to assess.