宁夏盐池县人地关系的演变及调适对策

对宁夏盐池县人地关系中的"人"子系统和"地"子系统进行了分析研究。"人"子系统的研究主要从人口数量、人口质量和人类行为3个方面着手;"地"子系统的研究主要从土地利用、耕地变化和地表植被变化3个方面着手。地表植被状况的变化用遥感卫星影像的归一化植被指数NDVI(normalized difference vegetation index)来综合反映。进而再运用相关分析法研究盐池县"人"子系统和"地"子系统的相互作用关系,并总结了其演变过程。分析发现宁夏盐池县人地关系系统存在的问题主要是:人口文化素质仍较差,劳动力文化水平偏低;掠夺式的人类行为导致"地"子系统的不断退化。进而相应提出了控制人口增长,加大劳动力转移力度,以减轻人口压力;提高种植业整体水平;通过合理的草地利用方式,从根本上缓解人地矛盾;多能互补,解决能源问题等调适对策。

Dynamics models of soil organic carbon

As the largest pool of terrestrial organic carbon, soils interact strongly with atmosphere composition, climate, and land change. Soil organic carbon dynamics in ecosystem plays a great role in global carbon cycle and global change. With development of mathematical models that simulate changes in soil organic carbon, there have been considerable advances in understanding soil organic carbon dynamics. This paper mainly reviewed the composition of soil organic matter and its influenced factors, and recommended some soil organic matter models worldwide. Based on the analyses of the developed results at home and abroad, it is suggested that future soil organic matter models should be developed toward based-process models, and not always empirical ones. The models are able to reveal their interaction between soil carbon systems, climate and land cover by technique and methods of GIS (Geographical Information System) and RS (Remote Sensing). These models should be developed at a global scale, in dynamically describing the spatial and temporal changes of soil organic matter cycle. Meanwhile, the further researches on models should be strengthen for providing theory basis and foundation in making policy of green house gas emission in China.

Structures and Electronic Properties of Cu_N (N≤13) Clusters

A systematic study on the structures and electronic properties of copper clusters has been performed using the density functional theory. In the calculation, there are many isomers near the ground state for small copper clusters. Our results show that the three-dimensional isomers of copper clusters start from Cu7 cluster and then show a tendency to form more compact structures. The results of the formation energy and the second derivative of binding energy with duster size show that besides N = 8, N =11 is also a magic number. Furthermore, it is the first time to find that the ground state of 11-atom clusters is a biplanar structure as same as the 13-atom cluster. The clear odd-even alternation as cluster size for the formation energy indicates the stability of electronic close shell existed in the range studied.

Dynamics of Quantum Entanglement in Reservoir with Memory Effects

The non-Markovian dynamics of quantum entanglement is studied by the Shabani-Lidar master equation when one of entangled quantum systems is coupled to a local reservoir with memory effects.The completely positive reduced dynamical map can be constructed in the Kraus representation.Quantum entanglement decays more slowly in the non-Markovian environment.The decoherence time for quantum entanglement can be markedly increased with the change of the memory kernel.It is found out that the entanglement sudden death between quantum systems and entanglement sudden birth between the system and reservoir occur at different instants.

How many cases of laryngopharyngeal reflux suspected by laryngoscopy are gastroesophageal reflux disease-related?

AIM:To investigate the prevalence of gastroesophageal reflux disease(GERD) in patients with a laryngoscopic diagnosis of laryngopharyngeal reflux(LPR).METHODS:Between May 2011 and October 2011,41 consecutive patients with laryngopharyngeal symptoms(LPS) and laryngoscopic diagnosis of LPR were empirically treated with proton pump inhibitors(PPIs) for at least 8 wk,and the therapeutic outcome was assessed through validated questionnaires(GERD impact scale,GIS;visual analogue scale,VAS).LPR diagnosis was performed by ear,nose and throat specialists using the reflux finding score(RFS) and reflux symptom index(RSI).After a 16-d wash-out from PPIs,all patients underwent an upper endoscopy,stationary esophageal manometry,24-h multichannel intraluminal impedance and pH(MII-pH) esophageal monitoring.A positive correlation between LPR diagnosis and GERD was supposed based on the presence of esophagitis(ERD),pathological acid exposure time(AET) in the absence of esophageal erosions(NERD),and a positive correlation between symptoms and refluxes(hypersensitive esophagus,HE).RESULTS:The male/female ratio was 0.52(14/27),the mean age ± SD was 51.5 ± 12.7 years,and the mean body mass index was 25.7 ± 3.4 kg/m 2.All subjects reported one or more LPS.Twenty-five out of 41 patients also had typical GERD symptoms(heartburn and/or regurgitation).The most frequent laryngoscopic findings were posterior laryngeal hyperemia(38/41),linear indentation in the medial edge of the vocal fold(31/41),vocal fold nodules(6/41) and diffuse infraglottic oedema(25/41).The GIS analysis showed that 10/41 patients reported symptom relief with PPI therapy(P < 0.05);conversely,23/41 did not report any clinical improvement.At the same time,the VAS analysis showed a significant reduction in typical GERD symptoms after PPI therapy(P < 0.001).A significant reduction in LPS symptoms.On the other hand,such result was not recorded for LPS.Esophagitis was detected in 2/41 patients,and ineffective esophageal motility was found in 3/41 patients.The MII-pH analysis showed an abnormal AET in 5/41 patients(2 ERD and 3 NERD);11/41 patients had a normal AET and a positive association between symptoms and refluxes(HE),and 25/41 patients had a normal AET and a negative association between symptoms and refluxes(no GERD patients).It is noteworthy that HE patients had a positive association with typical GERD-related symptoms.Gas refluxes were found more frequently in patients with globus(29.7 ± 3.6) and hoarseness(21.5 ± 7.4) than in patients with heartburn or regurgitation(7.8 ± 6.2).Gas refluxes were positively associated with extraesophageal symptoms(P < 0.05).Overall,no differences were found among the three groups of patients in terms of the frequency of laryngeal signs.The proximal reflux was abnormal in patients with ERD/NERD only.The differences observed by means of MII-pH analysis among the three subgroups of patients(ERD/NERD,HE,no GERD) were not demonstrated with the RSI and RFS.Moreover,only the number of gas refluxes was found to have a significant association with the RFS(P = 0.028 andP = 0.026,nominal and numerical correlation,respectively).CONCLUSION:MII-pH analysis confirmed GERD diagnosis in less than 40% of patients with previous diagnosis of LPR,most likely because of the low specificity of the laryngoscopic findings.

Updating of the hierarchical rock mass rating(HRMR) system and a new subsystem developed for weathered granite formations

The RMR system is still very much applied in rock mechanics engineering context. It is based on the evaluation of six weights to obtain a final rating. To obtain the final rating a considerable amount of information is needed concerning the rock mass which can be difficult to obtain in some projects or project stages at least with accuracy. In 2007 an alternative classification scheme based on the RMR, the Hierarchical Rock Mass Rating(HRMR) was presented. The main feature of this system was the adaptation to the level of knowledge existent about the rock mass to obtain the classification of the rock mass since it followed a decision tree approach. However, the HRMR was only valid for hard rock granites with low fracturing degrees. In this work, the database was enlarged with approximately 40% more cases considering other types of granite rock masses including weathered granites and based on this increased database the system was updated. Granite formations existent in the north of Portugal including Porto city are predominantly granites. Some years ago a light rail infrastructure was built in the city of Porto and surrounding municipalities which involved considerable challenges due to the high heterogeneity levels of the granite formations and the difficulties involved in their geomechanical characterization. In this work it is intended to provide also a contribution to improve the characterization of these formations with special emphasis to the weathered horizons. A specific subsystem applicable to the weathered formations was developed. The results of the validation of these systems are presented and show acceptable performances in identifying the correct class using less information than with the RMR system.

Marked Advance in Widths and Heights of Harmonic Plateau

We propose a scheme to simultaneously widen and heighten the high-order harmonic plateau on a large scale. More specifically, by adopting a united two-atom system with a suitable inter-nuclear separation instead of a single-atom, the harmonic plateau is widened from Ip ＋ 3.2Up to Ip ＋8.5Up; further, by adopting the combined pulse, the extended plateau （harmonics near Ip＋ 5.6Up） is selectively heightened in excess of 4 orders of magnitude compared with the case of the low-frequency pulse alone. By means of the wavelet transform for the induced dipole of these harmonics, a single x-ray pulse as short as 210 asec is achieved.

Spatial Data Process Using Python Script and Visual Programming Language in ArcGIS

Data are limitless. But those are usually not formed or created in our needs. Most of data providers deliver their data in Microsoft Excel spreadsheet, which is compatible with ArcGIS, the most widely used GIS （Geographic Information System） software in GIS sector. However, those table data contain much unnecessary information that do not need for a certain project. Using the raw data can increase processing times and reduce performance of geoprocessing tools. This study shows steps of how the raw data are being processed using ArcGIS ModelBuilder and Python script.

Efflux Estimate of Greenhouse Effect Gases in Three Different Forest Formations and the Influence of Soil

In carbon global cycle, the relationship between the terrestrial ecosystem and the atmosphere where there are, among others, gases that contribute to the greenhouse effect, has become object of relevant scientific interest. The content of organic matter in soil, expressed by its supplies as well as the organic matter degree of stability, are factors that can prevent the soil from acting as a drain and at the same time contribute for it to become a source of those gases. The variations in the way land is used in Brazil are factors responsible for the increase in emission of greenhouse effect gases. Based on these facts, this study was aimed to evaluate the CO2 and CH4 efflux using a gas retention chamber, and to associate these emissions to the organic carbon content in the soil. Two different areas were selected for the study, one in Tijuca Forest National Park, in a forest area, and the other at the Rio de Janeiro Federal Rural University campus. In the latter, the area was stratified in three sub areas according to the vegetation, use and water saturation degree. Samplings were performed during 8 months between 2013 and 2014.

Visualization and Damage Assessment for Flooded Area

A practical method for visualizing flood area and evaluating damage is presented, which consists of two technical approaches: self\|programming and adapting commercial GIS platforms. The low\|cost and easy\|to\|use GIS\|Based model developed by self\|programming can meet current requirements of most local authorities, especially in developing countries. In this model, two cases, non\|source flood and source flood, are distinguished and the Seed\|spread algorithm suitable for source\|flood is discussed; The flood damage is assessed by overlaying the flood area range with thematic maps and other related social and economic data. and all thematic maps are converted to raster format before overlay analysis. Two measures are taken to improve the operation efficiency of speed seed\|spread algorithm. The accuracy of the model mainly depends on the resolution and precision of the DEM data, and the accuracy of registering all raster layers and the quality of attribute data.

Correlation methods of base-level cycle based on wavelet neural network

The authors discussed the method of wavelet neural network （WNN） for correlation of base-level cycle. A new vectored method of well log data was proposed. Through the training with the known data set, the WNN can remenber the cycle pattern characteristic of the well log curves. By the trained WNN to identify the cycle pattern in the vectored log data, the ocrrdation process among the well cycles was completed. The application indicates that it is highly efficient and reliable in base-level cycle correlation.

Statistical measures of genetic differentiation of populations： Rationales, history and current states

Population differentiation is a fundamental process of evolution, and many evolutionary studies, such as population genetics, phylogeography and conservation biology, all require the inference of population differentiation. Recently, there has been a lot of debate over the validity of FST （and its analogue Gsr） as a measure for population genetic differentiation, notably since the proposal of the new index D in 2008. Although several papers reviewed or explored specific features of these statistical measures, a succinct account of this bewildering issue with an overall update appears to be desirable. This is the purpose of the present review. The available statistics generally fall into two categories, represented by Fsv and D, respectively. None of them is perfect in measuring population genetic differentiation. Nevertheless, they each have advantages and are valuable for current re- search. In practice, both indices should be calculated and a comparison of them can generate useful insights into the evolutionary processes that influence population differentiation. FsT （GsT） has some unique irreplaceable characteristics assuring its standing as the default measure for the foreseeable near future. Also, it will continue to serve as the standard for any alternative measures to contrast with. Instead of being anxious about making choice between these indices, one should pay due attention to the equili-brium status and the level of diversity （especially Hs） of the populations, since they largely sway the power of a given statistic to address a specific question. We provide a multi-faceted comparative summary of the various statistics, which can serve as a basic reference for readers to guide their applications [Current Zoology 61 （5）： 886-897, 2015].

Grid systems for geographic modelling and simulation:A review

Geography requires a comprehensive understanding of both natural and human factors,as well as their interactions.Due to the complexity and multiplicity of geographic problems,various theories and methods for geographic modelling and simulation have been proposed.Currently,geography has entered an era in which quantitative analysis and modelling are essential for understanding the mechanisms of geographic processes.As the basic idea of quantitative spatial analysis,the specified space often needs to be partitioned by a series of small computational units(cells),i.e.,grids.Thus,there is a close relationship between the grids and geographic modelling.This article reviews the mainstream and typical grids used for modelling and simulation.In addition to classification,the derived theories and technologies,including grid generation methods,data organization strategies,multi-dimensional querying methods,and grid adaptation techniques,are discussed.For integrated geographic simulation to explore comprehensive geographic problems,we argued that it is reasonable to build bridges among different types of grids(e.g.,transformation strategies),and more powerful grids that can support multi-type of numerical computation are urgently needed.

Soil microbes weaken the positive effect of an aquaticterrestrial subsidy on plant performance

Aims Linkages formed through aquatic-terrestrial subsidies can play an important role in structuring communities and mediating ecosystem functions.Aquatic-terrestrial subsidies may be especially important in nutrient-poor ecosystems,such as the freshwater sand dunes surrounding Lake Michigan.Adult midges emerge from Lake Michigan in the spring,swarm to mate and die.Their carcasses form mounds at the base of plants,where they may in crease plant productivity through their nutrient inputs.However,the effect of aquatic-terrestrial subsidies on plant productivity could depend on other biotic interactions.In particular,soil microbes might play a key role in facilitating the conversion of nutrients to plant-available forms or competing for the nutrients with plants.Methods In a greenhouse experiment,we tested how carcasses from lake emerge nt midges(Chironomidae)and soil microbes indepe ndently and interactively influe need the performance of a common dune grass,Calamovilfa longifolia.To determine whether midges influenced abiotic soil properties,we measured how midge additions influe need soil nutrients and soil moisture.Important Findings Midges greatly increased plant biomass,while soil microbes in flue need the magnitude of this effect.In the absence of soil microbes plant biomass was seven times greater with midges than without midges.However,in the presence of soil microbes,plant biomass was only three times greater.The effect of midges might be driven by their nutrient inputs into the soil,as midges contained 100 times more N,10 times more P and 150 times more K than dune soils did.Our results suggest that soil microbes may be competing with plants for these nutrients.In sum,we found that midges can be an important aquatic-terrestrial subsidy that produces strong,positive effects on plant productivity along the shorelines of Lake Michigan,but that the impact of aquatic-terrestrial subsidies must be considered within the context of the complex interactions that take place within ecological communities.

Phylogeography of Haplocarpha rueppelii(Asteraceae) suggests a potential geographic barrier for plant dispersal and gene flow in East Africa

East Africa is a biodiversity hotspot. Haplocarpha rueppelii （Sch.Bip.） Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation （intrinsic reproductive isolation and geographic barrier）. The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists＇ interests in phylogeography and biodiversity of East Africa.

Phylogeny of the Labeoninae （Teleostei, Cypriniformes） based on nuclear DNA sequences and implications on character evolution and biogeography

Abstract The Labeoninae is a subfamily of the family Cyprinidae, Order Cypriniformes. Oromandibular morphology within the Labeoninae is the greatest among cyprinid fishes. Although several phylogenetic studies about labeonines have been undertaken the results have been inconsistent and a comprehensive phylogeny is needed. Further, an incongruence between morphological and molecular phylogeny requires a systematic exploration of the significance of morphological characters on the basis of the molecular phylogeny. In this study, a total of 292 nucleotide sequences from 73 individuals （representing 24 genera and 73 species） of Labeoninae were analyzed. The results of the phylogenetic analysis indicate that there are four major clades within Labeoninae and three monophyletic lineages within the fourth clade. Results of the character evolution show that all oromandibular morphological characters are homoplastically distributed on the molecular phylogenetic tree and suggests that these characters evolved several times during the history of labeonines. In particular, the labeonine, a specific disc on the lower lip, has been acquired three times and reversed twice. These morphological characters do not have systematic significance but can be useful for taxonomy. The results of biogeography suggest that the Labeoninae originated from Southeast Asia and separately dispersed to Africa, East Asia and South Asia.

Bounding species distribution models

Species distribution models are increasing in popularity for mapping suitable habitat for species of management con- cern. Many investigators now recognize that extrapolations of these models with geographic information systems （GIS） might be sensitive to the environmental bounds of the data used in their development, yet there is no recommended best practice for ＂clamping＂ model extrapolations. We relied on two commonly used modeling approaches： classification and regression tree （CART） and maximum entropy （Maxent） models, and we tested a simple alteration of the model extrapolations, bounding ex- trapolations to the maximum and minimum values of primary environmental predictors, to provide a more realistic map of suit-able habitat of hybridized Africanized honey bees in the southwestern United States. Findings suggest that multiple models of bounding, and the most conservative bounding of species distribution models, like those presented here, should probably replace the unbounded or loosely bounded techniques currently used [Current Zoology 57 （5）： 642-647,2011].

Seasonal and diurnal variation in ecosystem respiration and environmental controls from an alpine wetland in arid northwest China

Wetlands store large amounts of carbon stocks and are essential in both global carbon cycling and regional ecosystem services.Understanding the dynamics of wetland carbon exchange is crucial for assessing carbon budgets and predicting their future evolution.Although many studies have been conducted on the effects of climate change on the ecosystem carbon cycle,little is known regarding carbon emissions from the alpine wetlands in arid northwest China.In this study,we used an automatic chamber system(LI-8100A)to measure ecosystem respiration(ER)in the Bayinbuluk alpine wetland in northwest China.The ER showed a significant bimodal diurnal variation,with peak values appearing at 16:30 and 23:30(Beijing time,UTC+8).A clear seasonal pattern in ER was observed,with the highest value(19.38μmol m-2 s-l)occurring in August and the lowest value(0.11μmol m-2 s-1)occurring in late December.The annual ER in 2018 was 678 g C m-2 and respiration during the non-growing season accounted for 13%of the annual sum.Nonlinear regression revealed that soil temperature at 5 cm depth and soil water content(SwC)were the main factors controlling the seasonal variation in ER.The diurnal variation in ER was mainly controlled by air temperature and solar radiation.Higher temperature sensitivity(Qio)occurred under conditions of lower soil temperatures and medium SWC(25%≤SWC≤40%).The present study deepens our understanding of CO,emissions in alpine wetland ecosystems and helps evaluate the carbon budget in alpine wetlands in arid regions.

The impact of burning on lion Panthera leo habitat choice in an African savanna

Camivores play a central role in ecosystem processes by exerting top-down control, while fire exerts bottom-up con- trol in ecosystems throughout the world, yet, little is known about how fire affects short-term carnivore distributions across the landscape. Through the use of a long-term data set we investigated the distribution of lions, during the daytime, in relation to burned areas in Serengeti National Park, Tanzania. We found that lions avoid burned areas despite the fact that herbivores, their prey, are attracted to burned areas. Prey attraction, however, likely results from the reduction in cover caused by burning, that may thereby decrease lion hunting success. Lions also do not preferentially utilize the edges of burned areas over unburned areas de- spite the possibility that edges would combine the benefit of cover with proximity to abundant prey. Despite the fact that lions avoid burned areas, lion territory size and reproductive success were not affected by the proportion of the territory burned each year. Therefore, burning does not seem to reduce lion fitness perhaps because of the heterogeneity of burned areas across the landscape or because it is possible that when hunting at night lions visit burned areas despite their daytime avoidance of these ar- eas .