情绪复杂性(emotional complexity)的本质在于情绪概念系统的分化和整合程度,其对个体的身心健康和社会适应有重要意义。Lane等于1987年编制了情绪觉察水平量表(Levels of Emotional Aw areness Scale,LEAS)来测量情绪复杂性,但由...情绪复杂性(emotional complexity)的本质在于情绪概念系统的分化和整合程度,其对个体的身心健康和社会适应有重要意义。Lane等于1987年编制了情绪觉察水平量表(Levels of Emotional Aw areness Scale,LEAS)来测量情绪复杂性,但由于其计分繁琐,展开更多
Pea ( Pisum sativum Linn.) actin gene family contains at least three isoforms (PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence...Pea ( Pisum sativum Linn.) actin gene family contains at least three isoforms (PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence in the untranslated regions. RT_PCR and Southern blotting using 3′_untranslated region (3′_UTR) as specific probe revealed that pea isoactin genes were expressed in roots, stems, leaves, tendrils, pollen and juvenile siliques, but displayed different patterns of transcript accumulation. Two_fold serial dilution electrophoresis showed PEAcⅠ mRNA preferentially accumulated in rapidly developing tissues: it peaked in seven days' stem; remained at a rather high level in leaves within a month but decreased significantly later; varied a little in tendrils and reached a median and a very low level respectively in juvenile siliques and in pollen. PEAcⅡ displayed somewhat similar expression pattern to PEAcⅠ. The observed differences in sequences and transcript accumulation patterns suggest that the individual pea actin genes may differ in their transcriptional regulation and cellular function. Phylogenetic tree of actins showed that pea actin isoforms are as diverged from each other as they are from other plant actins, and pea actins might have originated from a common ancestor before the divergence of the dicot and monocot plants.展开更多
Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuz...Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuzzy set are studied firstly, and then the cut set of interval fuzzy set is proposed. Moreover, the decomposition theo- rem, the representation theorem and the extension theorem of interval fuzzy set are presented. Finally, examples are given to demonstrate that the classical fuzzy set is a special case of interval fuzzy set and interval fuzzy set is an effective expansion of the classical fuzzy set.展开更多
The present article is an account of results on univalent functions in multiply connected domains obtained by the author. It contains two rery simple proofs of Villat's formula; Schwarz's formula, Poisson'...The present article is an account of results on univalent functions in multiply connected domains obtained by the author. It contains two rery simple proofs of Villat's formula; Schwarz's formula, Poisson's formula and Poisson-Jensen formula in multiply connected domains; the differentiability theorem with respect to the parameter of analytic function family containing one parametric variable on multiply connected domains; variation theorem and parametric representation theorem of univalent functions in multiply connected domains; the solution of an extremal problem of differentiable functionals.展开更多
Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods use...Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.展开更多
A new species,Thysanarthria rara sp.nov.,is described from China(Hunan,Guangdong).A photo of male genitalia of the new species is provided.This is the third known species in this genus from China.A key to all species ...A new species,Thysanarthria rara sp.nov.,is described from China(Hunan,Guangdong).A photo of male genitalia of the new species is provided.This is the third known species in this genus from China.A key to all species known from China is given.T.bifida Fikáček,2019 is recorded for the first time from Vietnam(Tonkin,Hoa-Binh).展开更多
A catastrophic landslide occurred at Xinmo village in Maoxian County, Sichuan Province,China, on June 24, 2017. A 2.87×106 m3 rock mass collapsed and entrained the surface soil layer along the landslide path. Eig...A catastrophic landslide occurred at Xinmo village in Maoxian County, Sichuan Province,China, on June 24, 2017. A 2.87×106 m3 rock mass collapsed and entrained the surface soil layer along the landslide path. Eighty-three people were killed or went missing and more than 103 houses were destroyed. In this paper, the geological conditions of the landslide are analyzed via field investigation and high-resolution imagery. The dynamic process and runout characteristics of the landslide are numerically analyzed using a depth-integrated continuum method and Mac Cormack-TVD finite difference algorithm.Computational results show that the evaluated area of the danger zone matchs well with the results of field investigation. It is worth noting that soil sprayed by the high-speed blast needs to be taken into account for such kind of large high-locality landslide. The maximum velocity is about 55 m/s, which is consistent with most cases. In addition, the potential danger zone of an unstable block is evaluated. The potential risk area evaluated by the efficient depthintegrated continuum method could play a significant role in disaster prevention and secondary hazard avoidance during rescue operations.展开更多
This study was conducted to investigate the effect of feeding different fibre feedstuffs on the performance, nutrient utilization and economics of production of weaning/growing pigs. Five fibre feedstuffs--palm kernel...This study was conducted to investigate the effect of feeding different fibre feedstuffs on the performance, nutrient utilization and economics of production of weaning/growing pigs. Five fibre feedstuffs--palm kernel cake (PKC), wheat offal (WO), corn bran (CB), rice bran (RB) and brewers' dried grain (BDG) were used at 25% in each of the five experimental diets that were formulated in this study. Twenty weaner pigs (12.75 ± 0.6 kg) were used for the growth study while 15 pigs (14.95 ± 0.57 kg) were used for the digestibility study. The design of the experiment was completely randomized. The results of the study showed that the performance of the experimental animals were significantly influenced (P 〈 0.05) by the dietary treatments. The apparent digestibility of the crude protein, crude fiber and ether extract showed significant differences (P 〈 0.05) while there was no significant difference (P 〉 0.05) in the apparent digestibility of their dry matter, ash and nitrogen free extract. The diet that contained WO had the best growth response and apparent nutrient digestibility. Results of economics of production also showed that diet with WO gave the best (P 〈 0.05) value in feed cost/'kg gain and net profit/animal. It can be concluded from this study that although all the animals fed the different fibre feedstuffs performed satisfactorily on all the parameters monitored, but for optimum growth, apparent nutrients digestibility and economics of production. WO should be used as a fibre feedstuff in the diets of weaning/growing pigs in the tropics.展开更多
This paper presents an efficient way to preserve the volume of implicit surfaces generated by skeletons. Recursive subdivision is used to efficiently calculate the volume. The criterion for subdivision is obtained by ...This paper presents an efficient way to preserve the volume of implicit surfaces generated by skeletons. Recursive subdivision is used to efficiently calculate the volume. The criterion for subdivision is obtained by using the property of density functions and treating different types of skeletons respectively to get accurate minimum and maximum distances from a cube to a skeleton. Compared with the criterion generated by other ways such as using traditional Interval Analysis, Affine Arithmetic, or Lipschitz condition, our approach is much better both in speed and accuracy.展开更多
Shallow surface wave methods are mostly used for investigation of the surface velocity structure in environmental and engineering geophysics in non-desert areas. For the special geological features of the Takelamagan ...Shallow surface wave methods are mostly used for investigation of the surface velocity structure in environmental and engineering geophysics in non-desert areas. For the special geological features of the Takelamagan Desert area, we use the multi-channel analysis of surface wave (MASW) method to process multi-channel shallow surface wave records to determine the near surface velocity structure in the desert area. We also process, analyze, and compare the surface waves in many-trace records extracted from the oil exploration shot gathers in the area. We show that the MASW method can determine detailed shallow velocity structure in desert areas and the many-trace records can be used to get detailed deep geological structure. The combination of the two different datasets can obtain the exact velocity structure upper 60 m depth in the survey area.展开更多
Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanza...Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1:50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base (FAO-WRB) for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/(+)kg to 24 cmol/(+)kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.展开更多
The map of reflecting horizon A, plotted on the basis of regional geophysical materials, yieldsinformation about the bottom topography of sedimentary cover of the West-Siberian Basin within Nadym-Taz interfluve. Throu...The map of reflecting horizon A, plotted on the basis of regional geophysical materials, yieldsinformation about the bottom topography of sedimentary cover of the West-Siberian Basin within Nadym-Taz interfluve. Through morphotectonic analysis about this surface, the authors are able tounderstand the distribution characteristics of the main topographic irregularities, with the blockstructure of the lower cover floors and underlying complexes as the focus.The largest irregularities are caused by the presence of three regional altitude steps, which show a regional tendency of basement being submerged in the north-north-east direction. Within these irregularities, the authors have distinguished some regions, which can be divided, based on the characteristics of morphostructural distribution, into two groups, i.e., areal (Nadym, Tol'ka, Urengoy)and belt (Tarko-Sale, Russko-Chasel'ka and Messoyakha). The first ones represent quasihomogeneous blocks, whose surfaces are complicated by irregular low-amplitude elevations and troughs and low-gradient zones with gradient values being up to 0.03, or they submerge stepwise, with the leveled areas being separated by zones with high gradients (0.07-0.15). The morphostructure of the other group of regions is characterized by the en-echelon distribution of contrastingly positive and negative elements with high values of slope gradients (higher than 0.1-0.2).展开更多
The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Est...The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary,and the roles of main environmental factors in distributing bacteria,are explored with observations from two cruises in June and August 2006.Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors.First,the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August.The phosphobacterial abundance and detection rates in August are much lower than those in June,but the denitrifying bacterial abundance becomes greater in August.However,the difference of heterotrophic bacterial abundance between June and August is not obvious.Second,main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase.Two parameters (salinity and NO3) in surface water and five environmental parameters (pH,salinity,PO43,NO3and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June,while different parameter combinations (salinity and PO43) in surface water and different parameter combinations (DO,DOC,NO3,PO43 and pH) in bottom water and surface sediment play major roles in August.Moreover,the bottom bacteria distributions in area south of 31 N are related to the position of the Taiwan Warm Current in June.The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase.During the hypoxia processes,the whole structure of bacterial functional groups probably turns to different states,causing the recycling of nutrient regeneration and aggravating hypoxia regionally.展开更多
In this paper, the spatial gravity distribution over Tibetan Plateau and the gravity rate of change at Lhasa for different Gaussian filter radii are computed using GRACE data. Results show that the estimate of the gra...In this paper, the spatial gravity distribution over Tibetan Plateau and the gravity rate of change at Lhasa for different Gaussian filter radii are computed using GRACE data. Results show that the estimate of the gravity rate of change is spatialradius-dependent of the Ganssian filter. The GRACE-estimated gravity rate of change agrees well with the surface measured one. In other words, the GRACE-estimated gravity rate of change has a limited value as that obtained by surface measurement when the spatial filter radius reaches zero. Then numerical simulations are made for different spatial radii of the Gaussian filter to investigate its behaviors when applied to surface signals. Results show that the estimate of a physical signal is filter-radius dependent. If the computing area is equal to or less than the mass area, especially for a uniformly distributed mass, the estimate gives an almost correct result, no matter what filter radius is used. The estimate has large error because of the signal leakage caused by harmonic truncation if the computing area is much bigger than the mass distribution (or inverse for a small mass anomaly). If a mass anomaly is too small, it is difficult to recover it from space observation unless the filter radius is extremely small. If the computing point (or area) is outside the mass distribution, the estimated result is almost zero, particularly for small filter radii. These properties of the Gaussian filter are helpful in applying GRACE data in different geophysical problems with different spatial position and geometrical size. We further discuss physical sources causing the scalar gravity change at Lhasa. Discussions indicate that the gravity rate of change at Lhasa is not caused by the present-day ice melting (PDIM) (or Little Ice Age, LIA) effect because no ice melting occurs in Lhasa city and nearby. The gravity rate of change is attributable mainly to tectonic deformation associated with the Indian Plate collision. Simultaneous surface displacement, surface denudation, and GIA effects are not negligible.展开更多
文摘情绪复杂性(emotional complexity)的本质在于情绪概念系统的分化和整合程度,其对个体的身心健康和社会适应有重要意义。Lane等于1987年编制了情绪觉察水平量表(Levels of Emotional Aw areness Scale,LEAS)来测量情绪复杂性,但由于其计分繁琐,
文摘Pea ( Pisum sativum Linn.) actin gene family contains at least three isoforms (PEAcⅠ, PEAcⅡand PEAcⅢ), and the DNA sequence of these isoforms show high similarity in the coding regions and significant divergence in the untranslated regions. RT_PCR and Southern blotting using 3′_untranslated region (3′_UTR) as specific probe revealed that pea isoactin genes were expressed in roots, stems, leaves, tendrils, pollen and juvenile siliques, but displayed different patterns of transcript accumulation. Two_fold serial dilution electrophoresis showed PEAcⅠ mRNA preferentially accumulated in rapidly developing tissues: it peaked in seven days' stem; remained at a rather high level in leaves within a month but decreased significantly later; varied a little in tendrils and reached a median and a very low level respectively in juvenile siliques and in pollen. PEAcⅡ displayed somewhat similar expression pattern to PEAcⅠ. The observed differences in sequences and transcript accumulation patterns suggest that the individual pea actin genes may differ in their transcriptional regulation and cellular function. Phylogenetic tree of actins showed that pea actin isoforms are as diverged from each other as they are from other plant actins, and pea actins might have originated from a common ancestor before the divergence of the dicot and monocot plants.
基金Supported by the Aeronautical Science Foundation(20115868009)the Open Project Program of Key Laboratory of Intelligent Computing&Information Processing of Ministry of Education in Xiangtan University(2011ICIP04)+1 种基金the Program of 211 Innovation Engineering on Information in Xiamen University(2009-2011)the College Students Innovation Training Plan of Xianmen University~~
文摘Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuzzy set are studied firstly, and then the cut set of interval fuzzy set is proposed. Moreover, the decomposition theo- rem, the representation theorem and the extension theorem of interval fuzzy set are presented. Finally, examples are given to demonstrate that the classical fuzzy set is a special case of interval fuzzy set and interval fuzzy set is an effective expansion of the classical fuzzy set.
文摘The present article is an account of results on univalent functions in multiply connected domains obtained by the author. It contains two rery simple proofs of Villat's formula; Schwarz's formula, Poisson's formula and Poisson-Jensen formula in multiply connected domains; the differentiability theorem with respect to the parameter of analytic function family containing one parametric variable on multiply connected domains; variation theorem and parametric representation theorem of univalent functions in multiply connected domains; the solution of an extremal problem of differentiable functionals.
基金supported by a grant from the Major State Basic Research Development Program of China (973 Program) (Grant No. 2015CB452706)National Natural Science Foundation of China (Grant No. 41471469)provided by the national scientific datasharing project Earth System Science Data Sharing Network
文摘Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(4) In addition, compared with traditional results, the revised result indicated that the population pressure was larger. Based on these results, the following conclusions were made:(1) the revised method for estimating population density that incorporates the RDLS is reasonable and practical,(2) the potential population pressure in the southeastern mountainous areas is substantial,(3) the characteristics of the terrain in the high mountainous areas are important for the scattered distribution of the population, and(4) the population distribution of mountainous areas in China should be guided by local conditions, such as social, economic, and topographic conditions.
基金GDAS Special Project of Science and Technology Development(2020GDSYL-20200102021,2020GDASYL-20200301003).
文摘A new species,Thysanarthria rara sp.nov.,is described from China(Hunan,Guangdong).A photo of male genitalia of the new species is provided.This is the third known species in this genus from China.A key to all species known from China is given.T.bifida Fikáček,2019 is recorded for the first time from Vietnam(Tonkin,Hoa-Binh).
基金Financial support from National Nature Science Foundation of China (Grant No. 41572303, 41520104002)Chinese Academy of Sciences “Light of West China” Program and Youth Innovation Promotion Association
文摘A catastrophic landslide occurred at Xinmo village in Maoxian County, Sichuan Province,China, on June 24, 2017. A 2.87×106 m3 rock mass collapsed and entrained the surface soil layer along the landslide path. Eighty-three people were killed or went missing and more than 103 houses were destroyed. In this paper, the geological conditions of the landslide are analyzed via field investigation and high-resolution imagery. The dynamic process and runout characteristics of the landslide are numerically analyzed using a depth-integrated continuum method and Mac Cormack-TVD finite difference algorithm.Computational results show that the evaluated area of the danger zone matchs well with the results of field investigation. It is worth noting that soil sprayed by the high-speed blast needs to be taken into account for such kind of large high-locality landslide. The maximum velocity is about 55 m/s, which is consistent with most cases. In addition, the potential danger zone of an unstable block is evaluated. The potential risk area evaluated by the efficient depthintegrated continuum method could play a significant role in disaster prevention and secondary hazard avoidance during rescue operations.
文摘This study was conducted to investigate the effect of feeding different fibre feedstuffs on the performance, nutrient utilization and economics of production of weaning/growing pigs. Five fibre feedstuffs--palm kernel cake (PKC), wheat offal (WO), corn bran (CB), rice bran (RB) and brewers' dried grain (BDG) were used at 25% in each of the five experimental diets that were formulated in this study. Twenty weaner pigs (12.75 ± 0.6 kg) were used for the growth study while 15 pigs (14.95 ± 0.57 kg) were used for the digestibility study. The design of the experiment was completely randomized. The results of the study showed that the performance of the experimental animals were significantly influenced (P 〈 0.05) by the dietary treatments. The apparent digestibility of the crude protein, crude fiber and ether extract showed significant differences (P 〈 0.05) while there was no significant difference (P 〉 0.05) in the apparent digestibility of their dry matter, ash and nitrogen free extract. The diet that contained WO had the best growth response and apparent nutrient digestibility. Results of economics of production also showed that diet with WO gave the best (P 〈 0.05) value in feed cost/'kg gain and net profit/animal. It can be concluded from this study that although all the animals fed the different fibre feedstuffs performed satisfactorily on all the parameters monitored, but for optimum growth, apparent nutrients digestibility and economics of production. WO should be used as a fibre feedstuff in the diets of weaning/growing pigs in the tropics.
文摘This paper presents an efficient way to preserve the volume of implicit surfaces generated by skeletons. Recursive subdivision is used to efficiently calculate the volume. The criterion for subdivision is obtained by using the property of density functions and treating different types of skeletons respectively to get accurate minimum and maximum distances from a cube to a skeleton. Compared with the criterion generated by other ways such as using traditional Interval Analysis, Affine Arithmetic, or Lipschitz condition, our approach is much better both in speed and accuracy.
文摘Shallow surface wave methods are mostly used for investigation of the surface velocity structure in environmental and engineering geophysics in non-desert areas. For the special geological features of the Takelamagan Desert area, we use the multi-channel analysis of surface wave (MASW) method to process multi-channel shallow surface wave records to determine the near surface velocity structure in the desert area. We also process, analyze, and compare the surface waves in many-trace records extracted from the oil exploration shot gathers in the area. We show that the MASW method can determine detailed shallow velocity structure in desert areas and the many-trace records can be used to get detailed deep geological structure. The combination of the two different datasets can obtain the exact velocity structure upper 60 m depth in the survey area.
文摘Despite the fact that miombo woodland soils have significant implications in global climate change processes, few studies have been done to characterize and classify the soils of the miombo woodland ecosystem of Tanzania. The current study was carried out to map and classify soils of Kitonga Forest Reserve, which is a typical miombo woodland ecosystem, in order to generate relevant information for their use and management. A representative study area of 52 km2 was selected and mapped at a scale of 1:50,000 on the basis of relief. Ten representative soil profiles were excavated and described using standard methods. Soil samples were taken from genetic soil horizons and analyzed in the laboratory for physico-chemical characteristics using standard methods. Using field and laboratory analytical data, the soils were classified according to the FAO-World Reference Base (FAO-WRB) for Soil Resources system as Cambisols, Leptosols and Fluvisols. In the USDA-NRCS Soil Taxonomy system the soils were classified as Inceptisols and Entisols. Topographical features played an important role in soil formation. The different soil types differed in physico-chemical properties, hence exhibit differences in their potentials, constraints and need specific management strategies. Texture varied from sandy to different loams; pH from 5.1 to 5.9; organic carbon from 0.9 g/kg to 20 g/kg; and CEC from 3 cmol/(+)kg to 24 cmol/(+)kg. Sustainable management of miombo woodlands ecosystem soils requires reduced deforestation and reduced land degradation.
文摘The map of reflecting horizon A, plotted on the basis of regional geophysical materials, yieldsinformation about the bottom topography of sedimentary cover of the West-Siberian Basin within Nadym-Taz interfluve. Through morphotectonic analysis about this surface, the authors are able tounderstand the distribution characteristics of the main topographic irregularities, with the blockstructure of the lower cover floors and underlying complexes as the focus.The largest irregularities are caused by the presence of three regional altitude steps, which show a regional tendency of basement being submerged in the north-north-east direction. Within these irregularities, the authors have distinguished some regions, which can be divided, based on the characteristics of morphostructural distribution, into two groups, i.e., areal (Nadym, Tol'ka, Urengoy)and belt (Tarko-Sale, Russko-Chasel'ka and Messoyakha). The first ones represent quasihomogeneous blocks, whose surfaces are complicated by irregular low-amplitude elevations and troughs and low-gradient zones with gradient values being up to 0.03, or they submerge stepwise, with the leveled areas being separated by zones with high gradients (0.07-0.15). The morphostructure of the other group of regions is characterized by the en-echelon distribution of contrastingly positive and negative elements with high values of slope gradients (higher than 0.1-0.2).
基金supported by the National Basic Research Program of China(2010CB428903)the Chinese offshore Investigation and Assessment Program(908-01-BC06)+5 种基金the National Marine Public Welfare Research Project of China(201305043-3)the Innovative Team of Key Science and Technology on Marine Aquaculture of Zhejiang Province(2010R50025)the Marine Science Foundation of State Oceanic Administration for Youth(2013140)the National Natural Science Foundation of China(41306112)the Zhejiang Provincial Natural Science Foundation(LY13D060004)the Basic Scientific Research Fundof SIO,China(JG1 311,JG1312)
文摘The distributions of N utilizing bacteria (denitrifying bacteria and ammonifying bacteria) ,P utilizing bacteria (organic phosphobacteria and inorganic phosphobacteria) and heterotrophic bacteria in the Changjiang Estuary,and the roles of main environmental factors in distributing bacteria,are explored with observations from two cruises in June and August 2006.Comparisons between the two important periods of initial hypoxia phase (June) and developed hypoxia phase (August) show differences in both bacterial distributions and the associated main environmental factors.First,the primary group of ammonifying bacteria has larger magnitude with spatial maximum value in the hypoxic stations related to sediment in August.The phosphobacterial abundance and detection rates in August are much lower than those in June,but the denitrifying bacterial abundance becomes greater in August.However,the difference of heterotrophic bacterial abundance between June and August is not obvious.Second,main environmental factors influencing bacteria vary from initial hypoxia phase to developed hypoxia phase.Two parameters (salinity and NO3) in surface water and five environmental parameters (pH,salinity,PO43,NO3and temperature) in bottom water and surface sediment play major roles in the bacterial abundance in June,while different parameter combinations (salinity and PO43) in surface water and different parameter combinations (DO,DOC,NO3,PO43 and pH) in bottom water and surface sediment play major roles in August.Moreover,the bottom bacteria distributions in area south of 31 N are related to the position of the Taiwan Warm Current in June.The bacterial abundance and distribution may respond to the environmental change in the hypoxia processes of initial phase and developed phase.During the hypoxia processes,the whole structure of bacterial functional groups probably turns to different states,causing the recycling of nutrient regeneration and aggravating hypoxia regionally.
基金study was supported by NASA’s Interdisciplinary Science Program (Grant No. NNG04GN19G)the Ohio State University Climate, Water, and Carbon Program
文摘In this paper, the spatial gravity distribution over Tibetan Plateau and the gravity rate of change at Lhasa for different Gaussian filter radii are computed using GRACE data. Results show that the estimate of the gravity rate of change is spatialradius-dependent of the Ganssian filter. The GRACE-estimated gravity rate of change agrees well with the surface measured one. In other words, the GRACE-estimated gravity rate of change has a limited value as that obtained by surface measurement when the spatial filter radius reaches zero. Then numerical simulations are made for different spatial radii of the Gaussian filter to investigate its behaviors when applied to surface signals. Results show that the estimate of a physical signal is filter-radius dependent. If the computing area is equal to or less than the mass area, especially for a uniformly distributed mass, the estimate gives an almost correct result, no matter what filter radius is used. The estimate has large error because of the signal leakage caused by harmonic truncation if the computing area is much bigger than the mass distribution (or inverse for a small mass anomaly). If a mass anomaly is too small, it is difficult to recover it from space observation unless the filter radius is extremely small. If the computing point (or area) is outside the mass distribution, the estimated result is almost zero, particularly for small filter radii. These properties of the Gaussian filter are helpful in applying GRACE data in different geophysical problems with different spatial position and geometrical size. We further discuss physical sources causing the scalar gravity change at Lhasa. Discussions indicate that the gravity rate of change at Lhasa is not caused by the present-day ice melting (PDIM) (or Little Ice Age, LIA) effect because no ice melting occurs in Lhasa city and nearby. The gravity rate of change is attributable mainly to tectonic deformation associated with the Indian Plate collision. Simultaneous surface displacement, surface denudation, and GIA effects are not negligible.