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991.
Impact of Holocene climate change on the prehistoric cultures of Zhejiang region,East China 总被引:1,自引:1,他引:0
Li Wu Cheng Zhu Chaogui Zheng Chunmei Ma Xinhao Wang Feng Li Bing Li Kaifeng Li 《地理学报(英文版)》2014,24(4):669-688
The temporal-spatial distribution features of prehistoric cultures since the Holocene in Zhejiang region were comparatively analyzed based on GIS spatial analysis. Results show that the prehistoric cultures expanded gradually in this region before 4000 cal. a BP. The notable expansions occurred twice, one in the Majiabang-Hemudu cultural period, the other in the Liangzhu cultural period. Meanwhile, the prehistoric cultures were disseminated from west to east coast along river valleys. After 4000 cal. a BP, as represented by the Maqiao Culture, the distributed area of each prehistoric culture contracted. This is obviously due to the termination of spreading trends to east coast, which was simultaneously accompanied by two different modes of production and economic transitions in the north and south Zhejiang region respectively. The distribution of prehistoric cultures was closely related with Holocene sea-level fluctuations, especially on the banks of Hangzhou Bay, where the distribution changes of prehistoric cultural sites were greatly affected by sea-level changes, with the closest relationships between them. After 7000 cal. a BP, the process of lowered sea-level and regression-epeirogenesis provided wider terrestrial living spaces for prehistoric inhabitants. Based on the comparative analyses of the changes of prehistoric cultures and the environmental evolution information recorded in the Qianmutian subalpine peat of Mt. Tianmu and muddy area on the inner shelf of the East China Sea, it is indicated that the changes of prehistoric cultures were synchronized with environmental changes in Zhejiang region. Before 4000 cal. a BP, the eastward expansion of prehistoric cultures in Zhejiang occurred under the background of the Holocene Optimum, and was the expansion and extension under the joint influences of agricultural civilization and maritime civilization. However, after 4000 cal. a BP, the geographical contraction of prehistoric cultures in Zhejiang occurred under the back ground of dry-cold climate trend and deterioration of coastal marine environment. It is evidenced from the above fact that the development, expansion and contraction of prehistoric cultures are positively correlated to environmental change. The change of the climatic environment is just the underlying reason for these changes and transitions of production modes and economic forms. Therefore, the climatic environment is the dominant factor of prehistoric culture vicissitudes in Zhejiang region, which has exerted great influence on distribution, dissemination, expansion and transmutation of the culture. 相似文献
992.
XIAO YingKai LIU WeiGuo MA YunQi ZHANG YanLing HE MaoYong LUO ChongGuang LIAO QingQiang 《中国科学:地球科学(英文版)》2014,57(5):1048-1060
To be used as proxies of seawater surface temperature(SST), the δ 18Oc values and Sr/Ca and Mg/Ca ratios of scleractinian coral skeletons must be verified by coral culture experiments in the laboratory. This paper describes a coral culture experiment that was conducted at several seawater temperatures T(21–28°C) using a tandem aquarium system and the new method for depositing coral skeletons grown under controlled conditions. The δ 18Oc values and the Sr/Ca and Mg/Ca ratios of the cultured coral were measured. We concluded that the δ 18Oc values and Sr/Ca and Mg/Ca ratios of the cultured coral are clearly correlated with T. The linear regression curve is δ18Oc(‰)=δ0.1427δT(°C)δ0.1495(n=18, r=0.955, p0.0001), and the slope of δ0.1427‰/°C is at the low end of the range of published values(δ0.13–δ0.29‰/°C). The Sr/Ca ratio decreases with increasing T, whereas the Mg/Ca ratio increases with increasing T, indicating a negative correlation between Sr/Ca and Mg/Ca. Their linear regression curves are Sr/Ca(mmol/mol)=δ0.04156δT+10.59(n=15, r=0.789, p0.005) and Mg/Ca(mmol/mol)= 0.04974δT+2.339(n=17, r=0.457, p0.05), respectively, which demonstrate that when Mg/Ca and Sr/Ca are increased by one unit, T increases by 5.19°C and decreases by 15.62°C, respectively. These variations are significantly lower than published values. 相似文献
993.
南京六朝文化旅游开发研究 总被引:3,自引:0,他引:3
文章分析了南京六朝文化旅游的开发现状,阐述了六朝文化的特征,在此基础上提出了开发规划的基本构思。六朝文化旅游的开发,既可进一步树立南京"六朝古都"的城市形象,又可成为南京旅游业新的生长点。 相似文献
994.
乡村文化与"三农"关系研究--以商丘市为例 总被引:5,自引:0,他引:5
中国传统文化和农业文化结合形成了乡村文化,农民在乡村文化环境中形成了"落后、封闭、固化、狭隘"的文化观念。千百年来,乡村文化观念已成为农民心理结构的主要成份,并对他们的思想感情、行为活动一直起着制约作用,进而影响着农业生产的发展和农村面貌的改变,解决"三农"问题的关键在于转变传统的乡村文化观念。因此,从根本上解决"三农"问题的策略是:首先提高农民文化素质,转变其乡村文化观念;其次是对农用土地进行规划整治,改变农村面貌,调整农业结构,促使农业全面发展;第三是加快城市化进程,实现城乡一体化,加强城乡文化交流、整合,使城乡共同发展。 相似文献
995.
Harmful algal blooms (HABs) have led to extensive ecological and environmental issues and huge economic losses. Various HAB control techniques have been developed, and biological methods have been paid more attention. Algicidal bacteria is a general designation for bacteria which inhibit algal growth in a direct or indirect manner, and kill or damage the algal cells. A metabolite which is strongly toxic to the dinoflagellate Alexandrium tamarense was produced by strain DH46 of the alga-lysing bacterium Alteromonas sp. The culture conditions were optimized using a single-factor test method. Factors including carbon source, nitrogen source, temperature, initial pH value, rotational speed and salinity were studied. The results showed that the cultivation of the bacteria at 28°C and 180 r min?1 with initial pH 7 and 30 salt contcentration favored both the cell growth and the lysing effect of strain DH46. The optimal medium composition for strain DH46 was determined by means of uniform design experimentation, and the most important components influencing the cell density were tryptone, yeast extract, soluble starch, NaNO3 and MgSO4. When the following culture medium was used (tryptone 14.0g, yeast extract 1.63g, soluble starch 5.0 g, NaNO3 1.6 g, MgSO4 2.3 g in 1L), the largest bacterial dry weight (7.36 g L?1) was obtained, which was an enhancement of 107% compared to the initial medium; and the algal lysis rate was as high as 98.4% which increased nearly 10% after optimization. 相似文献
996.
在浮筏式养殖中,海带的个体生产力与夹苗位置密切相关,上水层的海带长势较好.在育种中按照生产性状优劣的方法选种时,可被选种的个体仅占总个体的10%左右.本文采用同一对配子体无性繁殖系培育的克隆苗为实验材料,进行了个体生产力与夹苗位置之间的相关性分析.实验结果表明:在长度、宽度、厚度、鲜质量、干质量等各项指标中,干质量最能体现海带的个体生产力,得到方程式:y=-0.010x+0.387(R=0.933, P<0.01),该方程式表达了夹苗位置对海带个体生产力的影响.在海带育种选种时,利用公式y=0.010(n-1)+x,可以通过各个夹苗位置的实测值计算出最佳夹苗位置的期望值,消除因环境因素对海带个体生产力带来的影响,使实验结果之间有了可比性,能避免选种中的漏选或误选. 相似文献
997.
研究了獐子岛虾夷扇贝养殖区表层沉积物中Pb、Cd、Cu、Zn等有害重金属的含量及时空分布,并采用瑞典学者Hakanson的潜在生态危害指数法对该区域重金属的分布特征和生态风险进行了分析。结果表明,獐子岛海域表层沉积物Pb、Cd、Cu、Zn含量均是在夏季较低、冬季较高,最高含量分别为9.17±2.05、0.06±0.014、6.71±2.01、24.94 mg/kg±5.21 mg/kg,远低于国家一类海域标准及Hakanson提出的全球工业化前沉积物中相应污染物的背景值。综合评价,该海域表层沉积物中重金属的污染程度不具有生态风险性,整个养殖区养殖环境良好,为优良的贝类增养殖海域。 相似文献
998.
在分析岭南客家商帮形成的地理基础背景条件下,阐述了被迫外迁的部分从商客家人形成为客家商帮的历史过程,其可分为明中叶到清中后期的雏形期、鸦片战争后形成期和当代鼎盛期3个发展阶段;以客家会馆为标志,客家商帮在国内外的地域空间分布呈现出“国内以四川为中心,延及华南、华中,国外以东南亚为主体”的大分散、小集中的地域分布格局.与此相应,造就客家商帮开拓性、儒商性、包容性、务实性和诚信性的文化风格,并以此在商海竞争中取胜,与广州帮、潮州帮并立于中国商业文化版图. 相似文献
999.
为建立来源于锦鲤的细胞系,本文采用组织块法,对来源于锦鲤(Cyprinus carpio)鳍条、吻端、肌肉、心脏、鳔、肠道、卵巢等组织的细胞进行原代培养和传代培养.在25℃下,添加20%胎牛血清、0.2μg/mL表皮生长因子(EGF)和25ng/mL成纤维生长因子(FGF)的L-15培养基中进行培养.结果显示,鳍条、心脏、鳔、吻端、肌肉、肠道、卵巢分别在原代培养第3、6、12、13、15、3、3天,有细胞从组织块迁出;对长至单层的鳍条、心脏、肌肉细胞进行传代培养,鳍条细胞已传至第39代,心脏和肌肉细胞分别传到第2代和第4代;鳍条、心脏和肌肉细胞分别呈现上皮细胞样、上皮细胞样和上皮细胞样与成纤维状混合型.第6代锦鲤鳍细胞的染色体计数,结果显示,细胞染色体数目分布范围为55~154条,2n=100.病毒敏感性实验,发现锦鲤鳍条细胞对草鱼出血病病毒(GCRV)和鲤春病毒血症病毒(SVCV)都敏感,且在24h内出现细胞病变(CPE);但对斑点叉尾鮰病毒(CCV)不敏感.锦鲤鳍条细胞系的建立为后期建立更多的锦鲤细胞系和鱼类病毒研究奠定了基础. 相似文献
1000.
Marcel Fréchette 《Journal of Sea Research》2012,67(1):10-20
Future mussel suspension-culture methods may increasingly bypass standard population density adjustment on culture gear. This likely to exacerbate mussel fall-off. The potential extent of mussel fall-off is unknown. Here I use Dynamic Energy Budget theory and self-thinning theory to model the contribution of mussel fall-off to the total input of organic matter to the bottom. I focus on mussel populations grown on collector ropes and undergoing space-regulated self-thinning. Over a complete growth cycle, fall-off of mussel biomass was three times as high as the quantity harvested and accounted for 59% of total input of organic matter to the bottom. Biomass fall-off with collectors was 6-30 fold higher than with sleeving methods, as estimated from the literature. The relative contribution of mussel fall-off increased in a step-like fashion with initial population density, indicating that either mussels or biodeposits may dominate the organic input to the bottom, unless year-to-year variability in spat abundance is very high. The relative contribution of mussel fall-off did not increase appreciably with the intensity of second-set, but total mussel fall-off did. Assessment of each input type to the bottom is required for forecasting the consequences of a shift in culture methods, as they have different, spatially structured, effects on benthic environments. 相似文献