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阿拉善右旗位于内蒙古自治区的西部,生态环境较差,是我国沙尘暴的主要源区。阿拉善右旗的地表物质主要为沙漠和戈壁,为土地的沙漠化提供了丰富的物质来源,是生态环境恶化的物质基础。干旱的气候是阿拉善右旗生态环境脆弱化的关键因素,尤其是降水量和蒸发量之间的巨大差异,同时,频繁发生的沙尘暴等灾害性天气,对阿拉善右旗的生态环境恶化起到了推动作用。而青藏高原的不断隆升,造成该区的干暖化,是研究区生态环境趋于恶化的根本原因。而人类活动主要在恶化的气候环境中加速了生态环境恶化的进程。 相似文献
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矿企结构优化 开发利用和安全水平提高 生态环境改善内蒙古自治区国土资源厅组织开展了历时六年的矿产资源开发秩序的整顿规范工作,日前,矿业开发秩序日趋稳定,资源整合成效突出,矿政管理长效机制日益完善。2005年以来,内蒙古自治区国土资源厅就着力对矿产资源开发秩序进行规范整顿,首先对 相似文献
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Genetic engineering in filamentous N2-fixing cyanobacteria usually involves Anabaena sp. PCC 7120 and several other non-aggregating species. Mass culture and harvest of such species are more energy consuming
relative to aggregating species. To establish a gene transfer system for aggregating species, we tested many species of Anabaena and Nostoc, and identified Nostoc muscorum FACHB244 as a species that can be genetically manipulated using the conjugative gene transfer system. To promote biodegradation
of organophosphorus pollutants in aquatic environments, we introduced a plasmid containing the organophosphorus-degradation
gene (opd) into Anabaena sp. PCC 7120 and Nostoc muscorum FACHB244 by conjugation. The opd gene was driven by a strong promoter, P
psbA
. From both species, we obtained transgenic strains having organophosphorus-degradation activities. At 25°C, the whole-cell
activities of the transgenic Anabaena and Nostoc strains were 0.163±0.001 and 0.289±0.042 unit/μg Chl a, respectively. However, most colonies resulting from the gene transfer showed no activity. PCR and DNA sequencing revealed
deletions or rearrangements in the plasmid in some of the colonies. Expression of the green fluorescent protein gene from
the same promoter in Anabaena sp. PCC 7120 showed similar results. These results suggest that there is the potential to promote the degradation of organophosphorus
pollutants with transgenic cyanobacteria and that selection of high-expression transgenic colonies is important for genetic
engineering of Anabaena and Nostoc species. For the first time, we established a gene transfer and expression system in an aggregating filamentous N2-fixing cyanobacterium. The genetic manipulation system of Nostoc muscorum FACHB244 could be utilized in the elimination of pollutants and large-scale production of valuable proteins or metabolites. 相似文献
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2007年在内蒙古自治区呼伦贝尔市新巴尔虎左旗罕达盖地区开展1/5万矿产调查时,在原划分为中奥陶统多宝山组的灰岩中首次发现早泥盆世化石:牙形刺Pseudooneotodus beckmanni,Belodella resima,Belodella devonica,?Caudicriodus sp.;竹节石Nowakia sp.,?Homoctenus sp.;介形虫Tricornina sp.,Praepilatina sp.,Tetrasaculus sp.,Microcheilinella sp.,从而将这套缺少时代依据的地层确定为早泥盆世,归为泥鳅河组。 相似文献
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利用2003-2012年兰州市月均空气污染指数API和季节性时间序列模型SARIMA,对数据序列进行拟合并对其变化趋势进行了分析,研究其演变趋势并选取空气质量良好(月平均API150)的月份(2012年6月2013年2月),选用时间序列模型ARIMA(1,1,1)进行拟合,再结合残差控制图,对2013年3月日平均API预测监控。结果表明,SARIM A(0,1,1)×(0,1,1)12模型较好的拟合了近10年兰州市API的变化趋势,兰州市的空气污染大致呈冬、春季污染相对较重,夏、秋季相对较轻,空气质量总体在逐渐好转。适合该地区短时间尺度的时间序列模型是ARIMA(1,1,1),结合残差控制图对2013年3月API进行预测监控,结果显示6,9,10,11,12和13日超出控制限,对6日和9日提出预警。预测结果与实际结果相吻合,证实了将时间序列模型与残差控制图结合预测监控大气污染的有效性。 相似文献
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