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831.
中生代义马盆地不仅以中原唯一的中生代产煤盆地而著名,而且早中侏罗世的义马组含煤地层和晚三叠世地层中,保存了大量完美的各类动植物化石。长期以来,随着煤田勘查和开发,许多著名的地质、古生物学家进行了大量地质调查及地质古生物科学研究工作,取得了多项有世界性影响的科研成果。其中银杏化石植物群的发现,在世界上引起轰动,这是全世界迄今发现最古老的银杏化石群,被国际地质、古生物学术界命名为“义马银杏”, 相似文献
832.
833.
为贯彻落实《国土资源部关于加强地方和行业公益性地质调查队伍的意见》(国土资发[2003]358号)和温家宝总理关于“积极推进地质工作的根本转变,使地质工作更加紧密地与国民经济与社会发展相结台,更加主动地为经济与社会发展服务”的指示精神,河南省地质调查院在总结五年来承担国家国土资源大调查工作取得的成果的基础上,对夸后的发展提出了新的目标:巩固“两个战场”、打造“六大品牌”、抓好“三项重点”、做好“三个到位”和“三项服务”。 相似文献
834.
11月22日,由中国海洋学会、中国太平洋学会和河北省海洋局共同主办的第六届海洋强国战略论坛在石家庄市隆重召开。本届论坛以"保护渤海环境,推动海洋生态@明建设"为主题,提出举科学之力、聚专家之智,共同探讨海洋强国的战略内涵,探索决策海洋强国的理论,寻求建设海洋强 相似文献
835.
河南省地矿局第一地质调查队 《河南国土资源》2007,(9):49-49
我队创建于1957年,属于以地质找矿和科研为主的技术、知识密集型单位。主要从事区域地质调查和矿产地质勘查、水工环、地质灾害评价与治理等业务活动。有职工1131人, 相似文献
836.
Sediment-water fluxes of N and P species in the Bohai Sea were investigated in September-October 1998 and April-May 1999. The benthic fluxes of nutrient species were determined by incubating sediment core samples with bottom seawater bubbled with air or nitrogen. NO^-2,NH4, dissolved organic nitrogen (DON) and phosphorus (DOP), total dissolved nitrogen (TDN) and phosphorus (TDP), and PO4^3- showed a net exchange flux from seawater to sediment, while NO^-3, dissolved inorganic nitrogen (DIN) and SiO3^2- were released from sediment to seawater in the Bohai Sea. Sediment-water nutrient exchange increases DIN and reduces the phosphorus load in the Bohai Sea. The release of silicate from sediment to overlying seawater reduces potential silicate limitation of primary production resulted from decrease of riverine discharge.The exchange flux of nutrients showed no obvious seasonal variation. The present study showed that the concentrations and composition of nutrients in the water column were affected by suspended sediment, and that not all the exchangeable phosphate in sediment could be released via sediment resuspension. 相似文献
837.
LeQuocDoanh HaDinhTuan 《山地科学学报》2004,1(3):270-275
More than 30 ethnic groups are now living in northern mountainous regions, Vietnam, mainly relying on shifting cultivation with the fallow period being shortened from time to time. Naturally, soil fertility reduces from cycle to cycle, entailing the reduction of productivity. Large areas of moderately sloping lands suitable for upland agriculture have become bare after many cultivation-fallow cycles. The soils there have been severely degraded with more toxicity, low porosity, low water retention capacity and poor floral diversity. Normally, these lands cannot be used for food crop cultivation. So farmers in uplands have to rely on slash-and-burn practices for their livelihood. As there is no more forest with good soil in medium slopes, farmers go to cut forests in watershed, high slope lands and old forests up to the mountains‘ top. There are ecologically and environmentally very sensitive areas, so their destruction will inevitably cause hazardous consequences in the whole basin. Meanwhile,cultivation in these areas has low economic efficiency and sustainability because the crop yield may decrease very fast due to severe erosion as the higher the slope, the more serious erosion. Consequently living standards of highland farmers remain low and unstable. Sustainable farming on these lands in the perspective of a seriously deteriorated ecology and environmental is not an easy task. There have been many projects trying to help mountainous farmers get out of their vicious circle. However, due to different reasons, the results gained are low, and in some cases,things ceased to move after the projects phased out. During past few years, based on the farmer experiences, the Vietnam Agricultural Science Institute has cooperated with local and international partners to implement different projects in order to solve the problems by developing simple, easy and cheap cultivation technologies, which can be accepted and applied by local poor farmers for sustainable agricultural production. The first results of our activities offered good opportunities for sustain food production, improve soil health, recharge of aquifers,and enhanced household income for better rural lively hoods in the upland eco-regions of northern Vietnam. 相似文献
838.
西藏羊八井国家地质公园建设项目即将启动,这个由河南省地质调查院承担建设的项目是由河南省人民政府出资2000万元,对西藏实施的经济和技术的双重援助。 相似文献
839.
840.