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61.
Australian government attaches great importance to the management of wetland water environment and the implementation of advanced technology, and has made large processes in the recent decades. Australia is one of the best country in global for wetland management and technology implementation. Based on the analysis of Australian government working method for wetland water environment management, two wetland water environment management and technology dynamic integration cases, and on the comparason ofthe differences of wetland water environment management between the two countries, including Murray-Darling Basin (MDB) and Lake Eyre Basin (LEB), it can be concluded that the success of Australian wetland water environment management is because of the following reasons: the dynamic integration between department establishment and technology, the dynamic integration between public participation and monitoring technology, as well as the dynamic integration between innovation policy and advanced technology. Furthermore, entity management method such as Murray-Darling Basin Authority (MDBA) is more adaptable and has longer lifespan. Such virtual management method as Lake Eyre Basin Intergovernmental Agreement is more flexible and has lower cost. The lessons learned from Australian government can help China manage wetland water environment.  相似文献   
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the Kalpin nappe is an important multiple thrust system. It is important to study the Cenozoic tectonic of the Tianshan Mountain. Holocene active characteristics and paleoearthquake of the Kalpin nappe can be used to evaluate the neotectonic of this area. In this paper, we accurately measured the fault scarp in the front of three thrust-fold faults and analyzed paleoearthquake events in the trenches of the Kalpin nappe. Using the 10Be exposure age, we obtained those geomorphic surface ages and paleoearthquake times. The result showed that the slip rates of the west Kalpintag fault, aozitag fault and the tuoketag fault were 1.45(+1.68/-0.44) mm/a, 0.81(+0.35/-0.19) mm/a and (0.3±0.05) mm/a, respectively since the Holocene. The slip rate indicated that the increased activity transferred from back-row fault to front-row fault and accorded with the piggy-back propagation model in the Tianshan Mountain. Displacements and recurrence intervals of paleoearthquakes was similar to the slip rate characteristics. It also showed paleoearthquakes in the front row fault were stronger than paleoearthquakes of the back row fault. The strong paleoearthquake which caused the highest surface rupture happened in the Kalpintag fault. The interval of paleoearthquakes was about 4 ka and the displacement of every paleoearthquake was about 3 m in the west Kalpintag fault; the interval of paleoearthquakes was about 2 ka and the displacement of every paleoearthquake was about 1m in the aozitag fault; the tuoketag fault ruptured only one paleoearthquake since 7 ka. The Piqiang tear fault was the tectonic result of different shortening rate between the west Kalpin system and the east Kalpin system. The shortening rate of west Kalpin system was obviously stronger than the east Kalpin system. The huge separation distance was near 20 km between the east and the west back-row fault. Because the slip rate of system transferred to the front-row fault in the piggy-back propagation model, the separation distance (~4 km) between the east and the west front-row fault was increasing.  相似文献   
63.
我国石墨矿产地质特征及资源潜力分析   总被引:3,自引:0,他引:3  
肖克炎  孙莉  李思远  黄安 《地球学报》2016,37(5):607-614
石墨是我国重要的大宗优势非金属矿产,其既具有非金属矿物的一般性能,又兼有金属和有机塑料的某些特性,是用途广泛的特殊的非金属矿物原料,是我国新兴产业的重要原材料。我国石墨成因类型主要为区域变质型,其工业价值较大。文章通过对我国石墨矿产分布特征、成矿规律分析进而总结石墨资源潜力特征,认为我国黑龙江、内蒙古、四川等省资源潜力巨大,可实行保护性开采,从而获取经济效益。  相似文献   
64.
The Fengjia barite–fluorite deposit in southeast Sichuan is a stratabound ore deposit which occurs mainly in Lower Ordovician carbonate rocks. Here we present results from fluid inclusion and oxygen and hydrogen isotope studies to determine the nature and origin of the hydrothermal fluids that generated the deposit. The temperature of the ore‐forming fluid shows a range of 86 to 302 °C. Our detailed microthermometric data show that the temperature during mineralization of the fluorite and barite in the early ore‐forming stage was higher than that during the formation of the calcite in the late ore‐forming stage. The salinity varied substantially from 0.18% to 21.19% NaCl eqv., whereas the density was around 1.00 g/cm3. The fluid composition was mainly H2O (>91.33%), followed by CO2, CH4 and traces of C2H6, CO, Ar, and H2S. The dominant cation was Na+ and the dominant anion Cl, followed by Ca2+, SO42‐, K+, and Mg2+, indicating a mid–low‐temperature, mid‐low‐salinity, low‐density NaCl–H2O system. Our results demonstrate that the temperature decreased during the ore‐forming process and the fluid system changed from a closed reducing environment to an open oxidizing environment. The hydrogen and oxygen isotope data demonstrate that the hydrothermal fluids in the study area had multiple sources, primarily formation water, as well as meteoric water and metamorphic water. Combined with the geological setting and mineralization features we infer that the stratabound barite–fluorite deposits originated from mid–low‐temperature hydrothermal fluids and formed vein filling in the fault zone.  相似文献   
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Recent studies have indicated that in situ aerobic bioremediation is one of the most effective methods for remediating groundwater contaminated with nitrobenzene (NB). Aerobic bioremediation is largely dependent on the maintenance of adequate dissolved oxygen (DO) levels in the groundwater. Traditional in situ aeration has various disadvantages, such as high operational costs and nonuniform aeration. In this study, integrative cubes were prepared and utilized as a novel biological permeable reactive barrier (bio-PRB) medium to enhance the aerobic bioremediation of NB-contaminated groundwater. The results revealed an NB removal rate greater than 98.68% after 15–20 days of continuous oxygen release from the bio-PRB medium. DO concentrations reached 8.0 mg/L during treatment, and NB-degrading bacteria were able to tolerate a range of pH conditions. This multifaceted bio-PRB medium can simultaneously adsorb and biodegrade NB, release oxygen, and neutralize the pH with phosphate buffer. The results of this study suggest that this bio-PRB medium represents a highly effective in situ bioremediation method for NB-contaminated groundwater.  相似文献   
70.
卫星估雨精度的不确定性受到当地降雨类型和像元内降雨非均匀性影响,而结合这两个关键因素开展半干旱草原卫星估雨的研究有限.2009年夏,我们在中国锡林郭勒半干旱草原用多部微雨雷达和雨量计构建了9 km卫星像元降雨观测网,观测了像元内降雨非均匀性(空间变异系数CV),并评估了卫星估雨精度.结果表明:(1)CV值受像元内平均降雨量,降雨类型,降雨云面积及移向等影响,如高Cv值的降雨过程大多为平均降雨量小,对流性降雨过程,降雨云边缘像元CV值较高;(2)TRMM 3B42V7卫星估雨产品适用性较好,CMORPH和PERSIANN次之,但TRMM 3B42V7易在半干旱草原湖泊处高估降雨.  相似文献   
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