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991.
采用EGSB—SBR工艺处理实际果汁废水(COD 2 608~6 500 mg/L,p H 5.0~7.0)。在EGSB反应器成功启动及驯化完成的情况下,连续运行49 d。实验结果表明:第25天起,控制EGSB回流比为3.00∶1,EGSB反应器可在无须添加Na HCO3的条件下稳定运行,从而降低了废水处理成本;第25天起,平均进水COD,BOD5,SS分别为5 968,2 130,1 020 mg/L,平均出水COD,BOD5,SS分别降至131,11,50 mg/L,平均COD,BOD5,SS去除率分别为98%,99%,95%;组合工艺对该实际果汁废水具有良好的处理效果。 相似文献
992.
993.
E. Yu. Zakharova 《Russian Journal of Ecology》2012,43(2):162-168
Phenotypic variation in the widespread Siberian and Mongolian butterfly species Coenonympha amaryllis (Stoll, 1782), an indicator of undisturbed steppe communities, is analyzed. It is shown that its size variation is influenced
by a complex of climatic factors, the most important of them being the average starting date of the frost-free period and
average annual temperature in the region. Longitude-dependent variation in size is described by a “sawtooth curve” characteristic
of species with changing voltinism. 相似文献
994.
G. N. Tikhonova I. A. Tikhonov E. V. Kotenkova A. I. Munteanu I. G. Uspenskaya Yu. N. Konovalov V. I. Burlaku V. F. Kiku S. D. Georgitsa N. K. Karaman V. B. Nistreanu A. N. Mal’tsev 《Russian Journal of Ecology》2012,43(3):236-242
Comparative analysis of the structure of small mammal communities has been performed in two European cities located in different biomes: Chisinau (2008?C2009) and Yaroslavl (1994?C2002). The parameters studied included abundance, species composition, similarity and difference of faunas, species diversity, and proportions of groups differing in predisposition to synanthropy. It has been found that the structure of small mammal communities in these cities depends on specific physiographic conditions of the surrounding areas and on the distinctive features of the cities themselves (their structure, age, etc.). The similarity between the faunas is accounted for by the common ecological patterns of fauna formation in the biota of urban cenoses. 相似文献
995.
Expansion of cropland area and formation of the eastern farming-pastoral ecotone in northern China during the twentieth century 总被引:2,自引:0,他引:2
Land cover changes induced by historical cultivation in ecologically fragile areas involving important issues such as environmental change, ecology, and human sustainability are particularly worthy of attention. This paper reconstructs the spatial distribution of cultivated areas at the county level in the eastern farming-pastoral ecotone of northern China for four time periods during the twentieth century. The paper also analyzes how the location of cultivation ratio contours of 15 and 30 %, representing the boundaries of agricultural areas, have moved and the formation process of farming-pastoral ecotone patterns during this period. The study concludes that the area and ratio of cultivated land fluctuations increased during the twentieth century. The boundaries of the cultivation ratio contours of 15 and 30 % continually moved west and north. Moving north took priority over the other directions during the period of 1916–1940, when its center moved the farthest during the twentieth century, and the boundaries primarily moved westward during 1940–1980 and northwestward during 1980–2000. The distance, direction, and extent of the movement of the cultivation boundaries are all related to agricultural area expansion processes during this period, finally resulting in the creation of the modern farming-pastoral ecotone pattern. 相似文献
996.
塔里木河中游典型绿洲土壤含盐量的光谱特征 总被引:4,自引:0,他引:4
土壤含盐量是土地质量的一个重要因素。光谱反射率以快速获取和高质量等特点,在土壤研究方面广泛受到重视。选择塔里木河中游典型绿洲作为研究区,探讨了利用土壤光谱反射率来估算土壤含盐量,为该区域农业的可持续发展提供参考。首先,对土壤光谱反射率做了17种形式的变换,寻找能突现土壤含盐量的最佳的光谱波段。其次,对土壤光谱反射率与土壤含盐量进行耦合分析,建立了光谱反射率与含盐量的相关性方程。最后,使用统计软件SPSS16.0利用验证土壤验证方程的精度。结果显示,非盐渍土的最好估算方程为土壤光谱反射率的一阶微分形式,总均方根差RMSE为0.457。盐渍土的最好估算方程为对数倒数的二阶微分形式,总均方根差RMSE为0.523。结果表明,可以用土壤的光谱反射率间接测量土壤的含盐量,正确有效地指导农业生产。 相似文献
997.
Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify the response of ecosystem to LUCC based on ecosystem services valuation.With two-periods TM images,we got land use change data,and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi.Results showed that water area,farm land and unused land decreased while residential land,forest land,grassland and orchard land increased during the study period.The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area.As for spatial variation,there were most dramatically land use change and ESV decline in reservoir ecological protection region.The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable.The driving forces of ESV loss were rapid population growth and economic development.More work should be done to make eco-environment stay healthy. 相似文献
998.
针对湖域工业点源初始排污权定额配置问题,以“公平、效率、可行”为配置原则,通过引入权重系数的字典序最小化最大值方法,构建了基于多主体多种初始排污权多期配置的字典序定额模型,并给出求解算法。进而以江苏省太湖流域27类主要工业行业的初始氨氮排污权单期配置为例,从行业初始排污权短缺率与行业治污效益两方面,对比分析了基于等短缺率定额模型、等环境容量比例定额模型、字典序定额模型计算得到的3种定额配置方案效果。结果表明:相对于另外两种定额模型,字典序定额模型所得配置方案可实现平均行业短缺率最小(4613%),平均行业治污效益最大。研究也表明在“公平、效率、可行”配置原则下,字典序定额配置方法能够更为有效的促进企业治污技术提标升级和区域产业结构升级 相似文献
999.
基于DEM的山区旱灾风险评价模型——以西南地区为例 总被引:2,自引:0,他引:2
旱灾研究中,地形导致的水热再分配容易造成地域间旱灾灾情的明显差异,因此地形因子对于旱灾风险的准确评价及灾情的客观评估至关重要。采用气象站点观测数据和DEM数据,通过模拟复杂地形影响下的下垫面真实水分情况,加入地形因子的影响,建立了以干旱致灾因子(水分条件)、孕灾环境(地形)、承灾体(农作物脆弱性曲线)综合的旱灾风险评价三度模型;并以地形复杂、旱灾多发的西南地区为例,编制了旱灾风险等级图,以期为客观评估旱灾灾情,有效开展区域旱灾风险防范提供科学依据。 相似文献
1000.