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Content and densities of soil organic carbon in urban soil in different function districts of Kaifeng 被引量:16
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作者 SUN Yanli MA Jianhua LI Can 《Journal of Geographical Sciences》 SCIE CSCD 2010年第1期148-156,共9页
Urban soil, forming along with the development of city, has unique properties of soil organic carbon. On the basis of field investigation and laboratory analysis, soil organic carbon (SOC) of Kaifeng city was studie... Urban soil, forming along with the development of city, has unique properties of soil organic carbon. On the basis of field investigation and laboratory analysis, soil organic carbon (SOC) of Kaifeng city was studied, and the results showed that the characteristics of SOC were different not only among function districts in urban area, but also between urban area and suburbs. The order of SOC in topsoil was industrial district 〉 recreational district 〉 traffic district 〉 cultural/educational district 〉 residential/administrative district. The density of soil organic carbon (SOCD) in both topsoil and profile followed the orders of recreational district 〉 industrial district 〉 traffic district〉cultural/educational district 〉 residential/adminis-trative district, and cultural/educational district 〉 traffic district〉industrial district〉recreational district 〉 administrative/residential district, respectively. SOCD in both topsoil and profile decreased along the transection line from urban area to suburbs and urban area had 2.53-fold more SOCD in topsoil and 1.56-fold more SOCD in profile than suburbs, respectively. SOC decreased with the depth and was mainly distributed within the scope of 0-30 cm. The variances of SOC in urban area were more complicated than that in suburbs. 展开更多
关键词 Kaifeng city urban soil content of SOC SOCD
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Synthesis and Structure Investigation of a Transition Metal Ion Bridging Bis(diphosphopentamolybdates),[H_2BIIM]_3[HBIIM]_4[Mn(H_2O)_4(P_2Mo_5O_(23))_2]·7H_2O 被引量:6
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作者 魏林恒 王子梁 +1 位作者 赵俊伟 王敬平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期784-788,共5页
A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal struct... A novel transition metal ion bridging bis(diphosphopentamolybdates) has been synthesized and characterized by elemental analysis,IR spectrum,UV spectrum and single-crystal X-ray diffraction.The single-crystal structure analysis shows that the compound consists of seven charge-compensating 2,2'-biimidazole cations (BIIM=2,2'-biimidazole) and one dumbbell-like [Mn(H2O)4(P2Mo5O23)2]10-heteropolyanion which is constructed by two [P2Mo5O23]6-clusters bridged through one [Mn(H2O)4]2+ cation. 展开更多
关键词 POLYOXOMETALATE MOLYBDATE crystal structure dumbbell-like PHOSPHATE
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Synthesis and Structure of a Novel 3-Fold Interpenetrating Three-dimensional Coordination Polymer:[Ni(Hbyip^(2-))(bix)_(0.5)(H_2O)]_n 被引量:1
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作者 魏林恒 王子梁 +1 位作者 李明雪 王敬平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第4期486-491,共6页
A three-dimensional coordination polymer,[Ni(Hbyip2-)(bix)0.5(H2O)]n,has been hydrothermally synthesized.Each Ni2+ ion is five-coordinated by three carboxylate O atoms from three different 5-(benzoic acid-4-yl... A three-dimensional coordination polymer,[Ni(Hbyip2-)(bix)0.5(H2O)]n,has been hydrothermally synthesized.Each Ni2+ ion is five-coordinated by three carboxylate O atoms from three different 5-(benzoic acid-4-yldiazenyl)isophthalate(Hbyip2-) anions,one N atom from one 1,4-bis(imidazol-1-ylmethyl)benzene(bix) ligand and one O atom from an aqua ligand displaying a distorted square-pyramid.Each Ni atom is defined by three Hbyip2-anions and each Hbyip2-anion adopts a tris(mono-dentate) ligand coordinating to three Ni2+ ions affording a 36-membered inorganic ring.These rings are further arranged into an undulated two-dimensional layer parallel to the(101) plane.Adjacent two-dimensional networks are linked by bix ligands into a three-dimensional {63,83}{63} framework with a large channel(ca.26.3 × 13.6) along the [100] direction.Each individual {63,83}{63} network interpenetrates with two others in a parallel fashion to generate a 3-fold interpenetrating network. 展开更多
关键词 crystal structure coordination polymer CARBOXYLATE INTERPENETRATION transition metal
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Boron and Zinc Transport Through Intact Columns of Calcareous Soils
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作者 M. MAHMOOD-UL-HASSAN M. S. AKHTAR G. NABI 《Pedosphere》 SCIE CAS CSCD 2008年第4期524-532,共9页
Leaching of boron (B) and zinc (Zn) can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied us... Leaching of boron (B) and zinc (Zn) can be significant in some pedomorphic conditions, which can cause contamination of shallow groundwater and economic losses. Boron and Zn adsorption and transport was studied using 8.4 cm diameter × 28 cm long intact columns from two calcareous soil series with differing clay contents and vadose zone structures: Lyallpur soil series, clay loam (fine-silty, mixed, hyperthermic Ustalfic Haplargid), and Sultanpur soil series, sandy loam (coarse-silty, mixed, hyperthermic Ustollic Camborthid). The adsorption isotherms were developed by equilibrating soil with 0.01 tool L^-1 CaCl2 aqueous solution containing varying amounts of B and Zn and were fitted to the Langmuir equation. The B and Zn breakthrough curves were fitted to the two-domain convective-dispersive equation. At the end of the leaching experiment, 0.11 L 10 g L^-1 blue dye solution was also applied to each column to mark the flow paths. The Lyallpur soil columns had a slightly greater adsorption partition coefficient both for B and Zn than the Sultanpur soil columns. In the Lyallpur soil columns, B arrival was immediate but the peak concentration ratio (the concentration in solution at equilibrium/concentration applied) was lower than that in the Sultanpur soil columns. The breakthrough of B in the Sultanpur soil columns occurred after about 10 cm of cumulative drainage in both the columns; the rise in effluent concentration was fast and the peak concentration ratio was almost 1. Zinc leaching through the soil columns was very limited as only one column from the Lyallpur soil series showed Zn breakthrough in the effluent where the peak concentration ratio was only 0.05. This study demonstrates the effect of soil structure on B transport and has implications for the nutrient management in field soils. 展开更多
关键词 adsorption isotherm BORON intact soil column transport parameters ZINC
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Driving factors of forest landscape change in Yiluo River basin
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作者 LIANG Guofu DING Shengyan 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期415-422,共8页
The expansion of agriculture is posited as one of the main dynamics of forest landscape change globally, and the robust modeling of these processes is important for policy as well as academic concern. This paper conce... The expansion of agriculture is posited as one of the main dynamics of forest landscape change globally, and the robust modeling of these processes is important for policy as well as academic concern. This paper concerns a relatively small area of Yiluo River catchment where considerable attention has been paid to slow down the process of the expansion of agriculture into the remaining natural forests. In the present study, we reconstructed the former forest landscape structure and elucidated the landscape change during a period of about 15 years. Three sets (1987, 1996 and 2002) of maps derived from Landsat-5 images were used for analyses. The result showed that there was a decrease in the area of the forest landscape from 995.60 km2 in 1987 to 650.50 km2 in 2002. Then we examined the degree to which forest landscape conversion could be attributed to a set of factors identified as significant at broader scales, namely topography, distribution of the village clusters (centroids), distance from villages (centroids), and distance from forest edge (1987). By using "spatial analysis" in Arc/gis 8.3, the correlation between forest landscape change and driving factors was constructed. This study found that forest landscape conversion in this region was largely explained by elevation, slope and proximity to village. 展开更多
关键词 Luoning County agricultural expansion driving factors landscape change
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On the Live Coloration and Partial Mitochondrial DNA Sequences in the Topotypic Population of Goniurosaurus kuroiwae orientalis(Squamata: Eublepharidae), with Description of a New Subspecies from Tokashikijima Island, Ryukyu Archipelago, Japan
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作者 Masanao HONDA Hidetoshi OTA 《Asian Herpetological Research》 SCIE CSCD 2017年第2期96-107,共12页
Careful investigations of live coloration and other characters in the eublepharid gecko Goniurosaurus kuroiwae orientalis from Tonakijima Island, the type locality of the subspecies in the Central Ryukyus, Japan, reve... Careful investigations of live coloration and other characters in the eublepharid gecko Goniurosaurus kuroiwae orientalis from Tonakijima Island, the type locality of the subspecies in the Central Ryukyus, Japan, revealed its slight but consistent external differences from the consubspecific Tokashikijima population, whose phylogenetically divergent status against the former had been strongly suggested in a previous molecular study. A new subspecies, Goniurosaurus kuroiwae sengokui subsp. nov., is thus described for the Tokashikijima population. In life, Goniurosaurus k. sengokui subsp. nov. can be discriminated from G. k. orientalis in showing tint of reddish or pinkish, instead of yellowish, coloration in dorsal body pattern, and also usually darker and more or less reddish, instead of yellowish or grayish, iris in both adults and juveniles. Recalculation of sequence data at hand with relevant Gen Bank data confirmed substantial sequence divergences of G. k. sengokui from all other congeneric taxa of the Ryukyus described so far. 展开更多
关键词 Eublepharidae Goniurosaurus morphology taxonomy Ryukyu Archipelago
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More than Carbon Stocks:A Case Study of Ecosystem-based Benefits of REDD+ in Indonesia 被引量:6
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作者 LU Heli YAN Weiyang +1 位作者 QINYaochen LIU Guifang 《Chinese Geographical Science》 SCIE CSCD 2012年第4期390-401,共12页
During the 15th Conference of the Parties (COP 15), Parties agreed that reducing emissions from deforesta- tion and forest degradation and enhancing 'removals of greenhouse gas emission by forests' (REDD+) in d... During the 15th Conference of the Parties (COP 15), Parties agreed that reducing emissions from deforesta- tion and forest degradation and enhancing 'removals of greenhouse gas emission by forests' (REDD+) in developing countries through positive incentives under the United Nations Framework Convention on Climate Change (UNFCCC) was capable of dealing with global emissions. As REDD+ seeks to lower emissions by stopping deforestation and for- est degradation with an international payment tier according to baseline scenarios, opportunities for ecosystem benefits such as slowing habitat fragmentation, conservation of forest biodiversity, soil conservation may be also part of this effort. The primary objective of this study is to evaluate ecosystem-based benefits of REDD+, and to identify the rela- tionships with carbon stock changes. To achieve this goal, high resolution satellite images are combined with Normal- ized Difference Vegetation Index (NDVI) to identify historical deforestation in study area of Central Kalimantan, In- donesia. The carbon emissions for the period of 2000-2005 and 2005-2009 are 2.73 ×10^5 t CO2 and 1.47× 10^6 t CO2 respectively, showing an increasing trend in recent years. Dring 2005-2009, number of patches (NP), patch density (PD), mean shape index distribution (SHAPE_MN) increased 30.8%, 30.7% and 7.6%. Meanwhile, largest patch index (LPI), mean area (AREA MN), area-weighted mean of shape index distribution (SHAPE_AM), neighbor distance (ENN_MN) and interspersion and juxtaposition index (IJI) decreased by 55.3%, 29.7%, 15.8%, 53.4% and 21.5% re- spectively. The area regarding as positive correlation between carbon emissions and soil erosion was approximately 8.9 x l03 ha corresponding to 96.0% of the changing forest. These results support the view that there are strong syner- gies among carbon loss, forest fragmentation and soil erosion in tropical forests. Such mechanism of REDD+ is likely to present opportunities for multiple benefits that fall outside the scope of carbon stocks. 展开更多
关键词 REDD+ CARBON ecosystem-based benefits DEFORESTATION Indonesia
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Heavy Metal Pollution in Soils on Railroad Side of Zhengzhou-Putian Section of Longxi-Haizhou Railroad, China 被引量:8
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作者 MA Jian-Hua CHU Chun-Jie +1 位作者 LI Jian SONG Bo 《Pedosphere》 SCIE CAS CSCD 2009年第1期121-128,共8页
The pollution status and horizontal distribution of heavy metals (Ni, Pb, Cr, Zn, Cu, and Cd) in the soil on railroad side along the Zhengzhou-Putian section of Longxi-Haizhou Railroad were studied by collecting soil ... The pollution status and horizontal distribution of heavy metals (Ni, Pb, Cr, Zn, Cu, and Cd) in the soil on railroad side along the Zhengzhou-Putian section of Longxi-Haizhou Railroad were studied by collecting soil samples along a sampling section perpendicular to the railroad at the distances of 0, 10, 20, 30, 50, 100, 200, 300, and 500 m from the railroad edge. The concentrations of heavy metals in the sampling soils were higher than those of the control site. The concentrations of Pb, Zn, and Cd were found to be the highest in the soils at the railroad edge, and then decreased with increasing distance from the railroad. The highest concentrations of Ni, Cr, and Cu in soils were located at about 10-30 m from the railroad. Compared with the single factor pollution index (SFPI) of heavy metals calculated for the control site, the average SFPI from the sampling sites decreased in the order of Cr > Cd > Pb > Zn > Ni > Cu. There were notable negative correlations between the integral pollution index (IPI) of soil heavy metals at all sampling sites and the distances from the railroad. According to three IPIs calculated from the background values of heavy metals in och-aquic Cambisols, the heavy metal concentrations in the control soil, and the 2nd levels for soil heavy metals in GB15618-1995, the study area could be divided, based on the distances from the railroad, into four pollution zones: heavy pollution zone (0-10 m), medium pollution zone (10-50 m), slight pollution zone (50-100 m), and warning zone (100-500 m), respectively. 展开更多
关键词 heavy metals pollution index RAILROAD SOILS
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Linear nonadiabatic pulsation models of the double-mode Cepheid V371 Per
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作者 Toshihito Ishida 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第6期11-16,共6页
A recently found double-mode Cepheid with the shortest known period in our Galaxy and abnormal period ratio, V371 Per, is investigated by linear nonadiabatic pulsation models. V371 Per is likely to be crossing the ins... A recently found double-mode Cepheid with the shortest known period in our Galaxy and abnormal period ratio, V371 Per, is investigated by linear nonadiabatic pulsation models. V371 Per is likely to be crossing the instability strip for the first time, because the mass derived from pulsation models is larger than the evolution mass for the second or higher crossing objects. This result seems to support the conclusion obtained from spectroscopic observation. We also found that models with observed period and period ratio of V371 Per need to have mass and Teff in a narrow range which shifts as heavy element abundance Z changes. We have checked the agreement between Teffranges estimated observationally and derived from pulsation models using observational Z. We found that those ranges overlap marginally. We need more spectroscopic estimations of Teff and [Fe/H], and more photometric monitoring to estimate the evolutional period change for confirmation of our result. 展开更多
关键词 stars: oscillations (including pulsations) - stars variables Cepheids - stars individual (V371 Per)
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Areal differentiation of spermatophytic flora in Henan Province
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作者 ZHANG Guibin 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期223-230,共8页
Henan province, located between 110°21'E-116°39'E and 31°23'N-36°22'N, stretches from warm-temperate to subtropical transitional zone. Its special position and resultant varied physical conditi... Henan province, located between 110°21'E-116°39'E and 31°23'N-36°22'N, stretches from warm-temperate to subtropical transitional zone. Its special position and resultant varied physical conditions, in its long geologic history, give rise to not only a rich but also complex and prominently transitional flora. Therefore, in-depth study of the floristic areal differentiation is of importance to Chinese florilization and in accurately drawing the boundary of warm-temperate and subtropic zones in China. Based on the recent floristic data, this paper conducts comparison and analysis of the floristic difference and resemblance among the Dabie, Tongbai, Funiu and Taihang Mts. in Henan province. The result shows that the Dabie and the Tongbai Mts. have the similar flora components, the northern and the southern slopes of the Funiu Mts. have identical flora, but the Taihang Mts. stand alone in their floristic character. Therefore these mountainous areas should be grouped into three floral regions in China: the Dabie and the Tongbai Mts. belong to East China Floral Region, the Taihang Mts. to North China Floral Region, and the two slopes of the Funiu Mts.to Central China region. 展开更多
关键词 FLORA areal differentiation spermatophyte Henan province
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Role of Ca^(2+) on Growth of Brassica campestris L.and B.juncea(L.) Czern & Coss under Na^+ Stress
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作者 Badr-uz-Zaman M.Salim Rehana Asghar 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第6期549-555,共7页
Root and shoot growth of Brassica campestris L. and B. juncea increased significantly (P 〈 0.01) with enhanced Ca2+ treatment along with 60 mM NaCl in the root medium. The maximum fresh mass of shoot and root in B... Root and shoot growth of Brassica campestris L. and B. juncea increased significantly (P 〈 0.01) with enhanced Ca2+ treatment along with 60 mM NaCl in the root medium. The maximum fresh mass of shoot and root in B.juncea was recorded at 10 mM Ca2+ concentration. The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca2+ concentration. Average rate of Ca2+ intake (lCa) was higher in B. juncea than 6. campestris. In B. juncea, the average transport of Ca2+ to shoot increased by 19%, 38%, 119%, 125% and 169% compared with the control. Furthermore specific utilization rate of Ca2+ was higher in B. juncea than B. campestris. In B. campestris it increased by 9%, 32%, 41% and 59% at 4, 6, 8, and 10 mM of calcium in comparison to 2 mM Ca2+ treatment. At 4, 6, 8 and 10 mM of Ca2+ application, the increase in the leaf area ratio was 10,17, 23 and 30%, respectively. In the shoot and root portions of B. campestris and B.juncea, Ca2+ had a linear relationship with potassium and sulfur, whereas it was in antagonism with sodium ion. 展开更多
关键词 Coss under Na Czern STRESS
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Modeling the impacts of policy interventions from REDD+ in Southeast Asia: A case study in Indonesia
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作者 LU HeLi LIU GuiFang 《Science China Earth Sciences》 SCIE EI CAS 2014年第10期2374-2385,共12页
Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essen... Reducing Emissions from Deforestation and Forest Degradation(REDD+) and enhancing "removals of greenhouse gas emissions by forests" in developing countries through positive incentives is regarded as an essential component of the post-2012 climate regime for stabilizing greenhouse gas emissions and an important way of engaging developing countries in global mitigation efforts. We aimed to evaluate the potential effectiveness of REDD+ by integrating it into a land use option framework. One of our goals was to develop scenarios for evaluating the impacts of land use changes on carbon and environmental processes. In addition, we aimed to quantify the potential economic benefits to society of compensated reductions and to identify hotspots for applying REDD+. Three land use change scenarios were examined:(I) business as usual(BAU),(II) economic development, and(III) REDD+. A case study in Indonesia was examined using these land use scenarios and policy interventions, evaluating their effects on carbon emissions, socioeconomics, and environmental features of a spatial system using land use models. Significant emissions and water erosion reductions were predicted to be achieved under the REDD+ scenario, due to reduced deforestation of <6% over the next decade; >0.14 Mt CO2 e reduction was predicted relative to the BAU scenario. Furthermore, the spatial land use model indicated that REDD+ payments of forest carbon credits in the compliance market would play a key role in compensating rural communities and plantation companies for their opportunity cost in ending deforestation. This study provides an example of integrating land use modeling with a scenario analysis framework to evaluate plausible future forecasts and to evaluate the potential impacts of REDD+. 展开更多
关键词 deforestation and forest degradation greenhouse gas emissions land use Southeast Asia policy intervention
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