Climate warming has made the planting area of Hami melon expand northward to Barry Bakai Town,Altay City,near 47° N. Climate events often induce the occurrence of pests and diseases in crops,affecting the steady ...Climate warming has made the planting area of Hami melon expand northward to Barry Bakai Town,Altay City,near 47° N. Climate events often induce the occurrence of pests and diseases in crops,affecting the steady production of Hami melon. In 2013,pests and diseases occurred seriously,resulting in low yield and poor quality of Hami melon. Based on the production survey data of Hami melon in recent20 years,the interaction of various meteorological factors in different time and different intervals of various factors was analyzed in this paper to explore the characteristics of the meteorological factors that cause diseases and influence the quality of Hami melon.展开更多
Based on temperature,precipitation and sunshine data at Longhui National Station during 1981-2021,temperature at 22 regional stations during 2011-2021,and lily planting information of Longya Lily Base,the feasibility ...Based on temperature,precipitation and sunshine data at Longhui National Station during 1981-2021,temperature at 22 regional stations during 2011-2021,and lily planting information of Longya Lily Base,the feasibility of meteorological conditions for the growth of Lilium brownii var.viridulum was analyzed.The results showed that in general,the climatic conditions in Longhui were suitable for planting L.brownii var.viridulum.Among them,the south hilly area was the most suitable climate area,and the north mountain area was the suitable climate area,and the northwest mountain area was the more suitable climate area.It should sufficiently use the climatic conditions of Longhui,do a good job in meteorological service of L.brownii var.viridulum,and provide favorable meteorological guarantee for farmers,to reduce the impact of adverse meteorological conditions on L.brownii var.viridulum,and improve the economic benefits of lily production.展开更多
This work focuses on the performance comparison of monocrystalline and polycrystalline Si solar photovoltaic(SPV)modules under tropical wet and dry climatic conditions in east-central India(21.16°N 81.65°E,R...This work focuses on the performance comparison of monocrystalline and polycrystalline Si solar photovoltaic(SPV)modules under tropical wet and dry climatic conditions in east-central India(21.16°N 81.65°E,Raipur,Chhattisgarh).This study would help to select the SPV module for system installation in the east-central part of the country.For comparative analysis,we used performance ratio(PR)and efficiency as figures of merit.The plane-of-array(POA)irradiance was used to determine the efficiency of the modules.The decomposition and transposition models calculated the POA values from the measured global horizontal irradiance.The data were analysed systematically for 6 months in the non-rainy season,from October 2020 to March 2021.Special attention was given to solar irradiance,ambient temperature and module temperature-the parameters that affect the performance of PV modules.The month of October showed the highest variation in irradiance and temperature.The highest average module temperatures(51-52℃)were observed in October-November,while the lowest average module temperatures(34℃ for mono-Si and 36℃ for poly-Si)were observed in December.The highest value of average monthly POA irradiance(568 W/m^(2))was observed in February and the lowest(483 W/m^(2))in December.The results showed that the monocrystalline SPV module performed better than the polycrystalline module under all weather conditions.The maximum observed values of mono-Si and poly-Si panel PRs were 0.89 and 0.86,respectively,in December.展开更多
This paper is describing a detailed study of morphological structures and characteristics newborns thymus in different climatic and geographical conditions of Kara-Balta, Cholpon-Ata, and Bishkek in Kyrgyzstan. Anatom...This paper is describing a detailed study of morphological structures and characteristics newborns thymus in different climatic and geographical conditions of Kara-Balta, Cholpon-Ata, and Bishkek in Kyrgyzstan. Anatomical structure research done on 26 thymuses of newborn corpses. Research results showed that a significant amount of thymuses consisted of lobes with very thin connective tissues between them. It is observed that the Hassall cells were usually located in the medulla part of the thymus after using the coloring by Van-Gieson’s stain visible clear elastic and collagen fibers. In addition, cell population dynamics in a unit of conditional area of cortical substance thymus lobes in newborns determined.展开更多
Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenho...Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenhouses located at three cities in North,Northeast and Northwest China were predicted by CFD simulations of the greenhouse systems using typical meteorological data.The predicted temperatures based on the meteorological data in Shenyang are quite similar to the measured temperatures.The results also show that the external air temperatures and solar radiation fluxes play more important roles for the inside temperatures as indicated by the highest inner temperature in the morning on Feb.18 and from 10:00 to 14:00 on Feb.19 in Beijing and by the predicted temperatures inside the greenhouse being higher in Lanzhou than those in Shenyang and Beijing during most of the day.The average daily temperature inside the greenhouse in Lanzhou was nearly 3.5℃higher than that in Shenyang.Predicted air temperatures for various wall designs show that for single walls,the daily average interior temperatures in the aerated concrete wall greenhouse were higher than those in the brick wall and reinforced concrete wall greenhouses.However,the air temperature fluctuations were lower in the reinforced concrete wall greenhouse due to greater thermal storage capacity.The results also show that the temperatures in the layered wall greenhouses are quite similar,which coincides with the experimental results。展开更多
This article deals with the biochemical characteristics of varieties of Saint Mary’s Thistle such as Panacea, Debut and Samaryanka. Based on the studies, it was found that the highest oil content was found in the spe...This article deals with the biochemical characteristics of varieties of Saint Mary’s Thistle such as Panacea, Debut and Samaryanka. Based on the studies, it was found that the highest oil content was found in the species Debut (26%). <span style="font-family:Verdana;">The lowest oil content was observed in the variety </span><span style="font-family:Verdana;">Samaryanka</span><span style="font-family:Verdana;"> (19%). The highest protein content and the sum of total amino acids in the seeds of St. Mary’s Thistle varieties were found in the variety Debut (131.1), and the lowest indication was observed in the species Samaryanka (79.2). By the number of replaceable amino acids existing in the seeds of the species of St. Mary’s Thistle, it was found in the Varieties Debut (126.3), and the lowest indication was observed in the variety Samaryanka (112). Based on the results of studies and the noted biochemical characteristics and varietal differences of the St. Mary’s Thistle, the possibility and expediency of expanding the crops of this species in the soil and climatic conditions of the Khorezm region are suggested. The research was conducted 2017-2019 y.</span>展开更多
[ Objective]The research aimed to study influences of the climate conditions on organic agriculture and defense countermeasures of the meteorological disasters in Boshan District of Shandong. [ Method ] From climate r...[ Objective]The research aimed to study influences of the climate conditions on organic agriculture and defense countermeasures of the meteorological disasters in Boshan District of Shandong. [ Method ] From climate resources, relationships between meteorological conditions (tem- perature, water and sunshine, etc. ) and growth of the organic crops in Boshan District of Shandong were analyzed. 5-year development plan was put forward. Influences of the main meteorological disasters in growth process of the organic crops were analyzed. Moreover, corresponding de- fense countermeasures were put forward. [ Result] Due to monsoon influence in Boshan, rain and heat were in same season. Sunshine, heat and water coordinated well, and effectivity of the agricultural climate resources was higher. Qualities of the soil and water were good. Vegetation was complete. These conditions were all favorable for developing organic agricultural region. But the precipitation variability was big, which limited effec- tive utilizations of the sunshine and heat resources at different degrees. Meanwhile, in organic crops growth season when sunshine, heat and water were sufficient, meteorological disasters happened frequently. [ Conclusion] We should accelerate construction of the small water conservancy facil- ities, making rainstorm and flood as resources, and realizing timely watering. In addition, we ought to accelerate construction of the industrialized organic a clriculture to improve agricultural benefit.展开更多
Two-phase closed thermosyphons(TPCTs)are widely used in infrastructure constructions in permafrost regions.Due to different climatic conditions,the effectiveness of TPCT will also be different,especially in the extrem...Two-phase closed thermosyphons(TPCTs)are widely used in infrastructure constructions in permafrost regions.Due to different climatic conditions,the effectiveness of TPCT will also be different,especially in the extremely cold region of the Da Xing'anling Mountains.In this study,a series of three-dimensional finite element TPCT embankment models were established based on the ZhanglingMohe highway TPCT test section in Da Xing'anling Mountains,and the thermal characteristics and the cooling effect of the TPCTs were analyzed.The results indicated that the TPCTs installed in the northeastern high-latitude regions is effective in cooling and stabilizing the embankment.The working cycle of the TPCTs is nearly 7 months,and the cooling range of the TPCTs can reach 3 m in this region.However,due to the extremely low temperature,the TPCT generates a large radial gradient in the permafrost layer.Meanwhile,by changing the climate conditions,the same type of TPCT embankment located in the Da Xing'anling Mountains,the Xiao Xing'anling Mountains,and the Qinghai-Tibet Plateau permafrost regions were simulated.Based on the comparison of the climate differences between the Qinghai-Tibet Plateau and Northeast China,the differences in the effectiveness of TPCTs were studied.Finally,the limitations of using existing TPCTs in high-latitude permafrost regions of China were discussed and the potential improvements of the TPCT in cold regions were presented.展开更多
AIM:To study the normal aerobic conjunctival flora in lower to mid Himalayan region of Shimla Hills.METHODS:Samples from normal conjunctiva of 200 individuals above the age of 13 years who visited Indira Gandhi Medica...AIM:To study the normal aerobic conjunctival flora in lower to mid Himalayan region of Shimla Hills.METHODS:Samples from normal conjunctiva of 200 individuals above the age of 13 years who visited Indira Gandhi Medical College Hospital Shimla for refraction or cataract surgery were taken by anaesthetising the conjunctival sac with sterile 4% Xylocaine solution.Samples were obtained by gently rubbing lower fornix with a sterile cotton wool swab moistened with normal saline and keeping the eye lids wide apart to avoid contamination from lid margins.It was immediately inoculated in Brain Heart infusion and subjected to standard aerobic culture and identification techniques.RESULTS:Totally,72 eyes(36%) conjunctival sacs were sterile.Predominant aerobes isolated were Staphylococcus spp.in 120(60%) followed by Haemophilus in 16(8%),diphtheroids in 10(5%),and Escherichia coli(E.coli) in 4(2%).A single aerobe was isolated from 98 eyes(49%) while 30 eyes(15%) yielded more than 1 aerobe.Staphylococcus epidermidis(S.epidermidis) was the most common bacterium,found alone in 58 eyes(29%) and in combination with another aerobe in 30 eyes(15%),followed by Staphylococcus aureus(S.aureus) in 18(9%) and 10 eyes(5%) respectively.CONCLUSION:S.epidermidis is the most common commensal organism followed by Haemophilus species.diphtheroids occupied the third position which otherwise are found more abundantly in literature.Pathogens like S.aureus,Staphylococcus citreus and E.coli were also found.Therefore,preoperative administration of topical broad spectrum antibiotics is extremely important in prophylaxis against ocular infection.The variation in microflora of normal conjunctiva in this part of world can be attributed to geographical,climatic and ethnic characteristics of the population under study.展开更多
The mountainous forests in arid regions, being sensitive to climate change, are one of the key research topics related to the mechanism of interaction between climate and the terrestrial ecosystem. In this study, the ...The mountainous forests in arid regions, being sensitive to climate change, are one of the key research topics related to the mechanism of interaction between climate and the terrestrial ecosystem. In this study, the spatial distribution of a mid-mountain forest and its environmental factors were investigated by using a combination of remote sensing technology, field survey, climate indices and soil nutrient analysis in the Sangong River watershed of the northern Tianshan Mountains. The forest (Picea schrenkiana) was distributed between 1,510 and 2,720 m asl. Tree height and diameter at breast height (DBH) exhibited a bi-modal pattern with increasing elevation, and rested at 2,450 and 2,250 m asl, respectively. The two maxima of DBH appeared at 2,000 and 2,550 m asl, and the taller trees were observed at 2,100 and 2,600 m asl. For the annual mean temperature, the difference was approximately 5.8℃ between the lowest and the highest limits of the forest, and the average decreasing rates per hundred meters were 0.4g℃ and 0.55℃ with increasing altitude between 1,500 and 2,000 m asl and above 2,000 m asl, respec- tively. The annual precipitation in the forest zone first increased and then decreased with the increase of altitude, and the maximum value was at 2,000 m asl. For per hundred meters, the annual precipitation increased with the rate of 31 mm between 1,500 and 2,000 m asl and decreased by 7.8 mm above 2,000 m asl. The SOM, TN and TP were high between 2,000 and 2,700 m asl and low at the lower and upper forest limits. The minimum CaCO3 con- centration, pH value and EC coincided with the maximum precipitation belt at 2,000 m asl. The SOM, TN and TP were high in the topsoil (0-10 cm) and differed significantly from the values observed in the deep soil layers (〉10 cm). The soil nutrients exhibited spatial heterogeneity and higher aggregation in the topsoil. In conclusion, soil and climate are closely related to each other, working synergistically to determine the development and spatial distribution of the mid-mountain forest in the study area. The order of the importance of environmental factors to forest development in this study is as follows: soil nutrients〉precipitation〉elevation〉temperature.展开更多
To study the sensitivity of inter-subspecific hybrid rice to climatic conditions, the spikelet fertilized rate (SFR) of four types of rice including indica-japonica hybrid, intermediate hybrid, indica and japonica w...To study the sensitivity of inter-subspecific hybrid rice to climatic conditions, the spikelet fertilized rate (SFR) of four types of rice including indica-japonica hybrid, intermediate hybrid, indica and japonica were analyzed during 2000-2004. The inter-subspecific hybrids showed lower SFR, and much higher fluctuation under various climatic conditions than indica and japonica rice, showing the inter-subspecific hybrids were sensitive to ecological conditions. Among 12 climatic factors, the key factor affecting rice SFR was temperature, with the most significant factor being the average temperature of the seven days around panicle flowering (T7). A regressive equation of SFR-temperature by T7, and a comprehensive synthetic model by four important temperature indices were put forward. The optimum temperature for inter-subspecific hybrids was estimated to be 26.1-26.6℃, and lower limit of safe temperature to be 22.5-23.3℃ for panicle flowering, showing higher by averagely 0.5℃ and 1.7℃, respectively, to be compared with indica and japonica rice. This suggested that inter-subspecific hybrids require proper climatic conditions. During panicle flowering, the suitable daily average temperature was 23.3-29.0℃, with the fittest one at 26.1-26.6℃. For an application example, optimum heading season for inter-subspecific hybrids in key rice growing areas in China was as same as common pure lines, while inferior limit for safe date of heading was about a ten-day period earlier than those of common pure lines.展开更多
Water is a vital resource.It supports a multitude of industries,civilizations,and agriculture.However,climatic conditions impact water availability,particularly in desert areas where the temperature is high,and rain i...Water is a vital resource.It supports a multitude of industries,civilizations,and agriculture.However,climatic conditions impact water availability,particularly in desert areas where the temperature is high,and rain is scarce.Therefore,it is crucial to forecast water demand to provide it to sectors either on regular or emergency days.The study aims to develop an accurate model to forecast daily water demand under the impact of climatic conditions.This forecasting is known as a multivariate time series because it uses both the historical data of water demand and climatic conditions to forecast the future.Focusing on the collected data of Jeddah city,Saudi Arabia in the period between 2004 and 2018,we develop a hybrid approach that uses Artificial Neural Networks(ANN)for forecasting and Particle Swarm Optimization algorithm(PSO)for tuning ANNs’hyperparameters.Based on the Root Mean Square Error(RMSE)metric,results show that the(PSO-ANN)is an accurate model for multivariate time series forecasting.Also,the first day is the most difficult day for prediction(highest error rate),while the second day is the easiest to predict(lowest error rate).Finally,correlation analysis shows that the dew point is the most climatic factor affecting water demand.展开更多
Study of the climate variability in the past and present, and correlating those with changes in the distribution range of species has attracted considerable research interest. The genus Ablepharus consists of 10 recog...Study of the climate variability in the past and present, and correlating those with changes in the distribution range of species has attracted considerable research interest. The genus Ablepharus consists of 10 recognized species, of which A. bivittatus, A. grayanus and A. pannonicus are documented from Iran. In the present study, we modeled with MaxEnt the potential distribution areas and determined the suitable habitats in past (mid-Holocene [MH], and the Last Interglacial [LIG]) and their current distribution for two species of snake-eyed skinks (A. grayanus and A. pannonicus) separately. Models of the species indicated good fit by the average high area under the curve (AUC) values (A. grayanus = 0.929 4- 0.087 and A. pannonicus = 0.979 4- 0.007). Precipitation of the driest quarter of the year, mean temperature of the coldest quarter of the year, and precipitation of the driest month variables made important contributions to A. grayanus. Two important climate variables contributed importantly to A. pannonicus; temperature seasonality, and mean temperature of the wettest quarter of the year, and one topographic variable, slope. We conclude that these variables form a natural barrier for species dispersal. The MH and the LGM models indicated a larger suitable area than the current distribution.展开更多
Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.I...Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.In this regard,the research proposes to construct the correlation between climatic design conditions and indoor thermal environment risk level,and explore the effect of uncertainty in building thermal performance on this correlation from the perspective of probability,thus realizing the process of selecting the climatic design conditions based on the requirement for indoor thermal environment risk level.Taking Guangzhou in China as an example,the new process of determining climatic design conditions is realized.On this basis,the difference between the traditional method and the present research method is compared.In the Chinese norm method,the indoor thermal environ-ment risk level of the building is between 0 and 0.03%when the climatic design conditions are selected with 0.57%cumulative frequency of occurrence;in the research method,the indoor thermal environment risk level of the building is between 0.2%and 0.6%when the climatic design conditions are selected with 0.57%indoor thermal environment risk level and 100%confidence level.The results indicate that the research method can meet the designer’s expectation for indoor thermal environment risk level in design more directly and accurately.展开更多
Microbes are decomposers of crop residues,and climatic factors and residue composition are known to influence microbial growth and community composition,which in turn regulate residue decomposition.However,the success...Microbes are decomposers of crop residues,and climatic factors and residue composition are known to influence microbial growth and community composition,which in turn regulate residue decomposition.However,the succession of the bacterial community during residue decomposition in Northeast China is not well understood.To clarify the property of bacterial community succession and the corresponding factors regulating this succession,bags containing maize residue were buried in soil in Northeast China in October,and then at different intervals over the next 2 years,samples were analyzed for residue mass and bacterial community composition.After residue burial in the soil,the cumulative residue mass loss rates were 18,69,and 77%after 5,12,and 24 months,respectively.The release of residue nitrogen,phosphorus,and carbon followed a similar pattern as mass loss,but 79%of residue potassium was released after only 1 month.The abundance,richness,and community diversity of bacteria in the residue increased rapidly and peaked after 9 or 20 months.Residue decomposition was mainly influenced by temperature and chemical composition in the early stage,and was influenced by chemical composition in the later stage.Phyla Actinobacteria,Bacteroidetes,and Firmicutes dominated the bacterial community composition in residue in the early stage,and the abundances of phyla Chloroflexi,Acidobacteria,and Saccharibacteria gradually increased in the later stage of decomposition.In conclusion,maize residue decomposition in soil was greatly influenced by temperature and residue composition in Northeast China,and the bacterial community shifted from dominance of copiotrophic populations in the early stage to an increase in oligotrophic populations in the later stage.展开更多
Under global warming, seasonal snow takes faster melting rate than before, which greatly changes the hydro-logical cycle. In this study, by targeting three typical seasonal snow-covered land types (i.e., open shrublan...Under global warming, seasonal snow takes faster melting rate than before, which greatly changes the hydro-logical cycle. In this study, by targeting three typical seasonal snow-covered land types (i.e., open shrubland,evergreen needleleaf forest and mixed forest) in the Northern Hemisphere, the start of growing season (SGS) hasbeen found obviously advanced in the past years, greatly contributed by the faster melting rate of seasonal snow.It is manifested that significantly positive correlation has been found between SGS and May snow depth for openshrubs, March and April snow depth for evergreen needleleaf forests and March snow depth for mixed forests.However, such close association is not appeared in all the climate conditions of same vegetation. In the future,as the rate of melting snow becomes faster in the high emission of greenhouse gasses than the current situation,continuously advanced SGS will accelerate the change of vegetation distribution in the Northern Hemisphere.These findings offer insights into understanding the effect from seasonal snow on vegetation and promote thesustainable utilization of regional vegetation in the Northern Hemisphere.展开更多
Sandstones sampled from Patti Formation,Southern Bida Basin,were studied geochemically using Inductively Coupled Plasma Atomic Emission Spectrophotometer(ICP-AES)and an Inductively Coupled Plasma Mass Spectrometry(ICP...Sandstones sampled from Patti Formation,Southern Bida Basin,were studied geochemically using Inductively Coupled Plasma Atomic Emission Spectrophotometer(ICP-AES)and an Inductively Coupled Plasma Mass Spectrometry(ICP-MS)technique to evaluate their weathering and tectonic setting as well as to deduce the paleo-climatic conditions that existed during their deposition.Geochemically,SiO_(2)range from 73.9%to 86.2%,Al_(2)O_(3)(6.7%~17.1%),Fe_(2)O_(3)(1.1%~1.9%),K_(2)O(0.1%~0.7%)while MgO,CaO,Na_(2)O,P_(2)O_(5),MnO and TiO_(2)were<1%.Enriched in Ba(Av.622.94),Sr(Av.153.63),Rb(Av.55.08)and Zr(Av.51.86)relatively similar in composition to UCC.High SiO_(2)but low other major oxides signify high mobility during processes of weathering.This was confirmed by high value(>80%)for indices like chemical index of alteration,chemical index of weathering,plagioclase index of alteration,mineralogical index of alteration and relatively lower values for weathering index of parker,recently used alpha indices(α^(Al)_(E))of sodium(326.17α^(Al)_(Na)<344.40),magnesium(100.54α^(Al)_(mg)<398.55),calcium(12.07α^(Al)_(Ca)<198.99),potassium(4.43α^(Al)_(K)<64.33),strontium(0.84α^(Al)_(E)<21.40),barium(0.45α^(Al)_(Ba)<10.52)and rubidium(0.0008α^(Al)_(Rb)<0.06),supported by AI_(2)O_(3)-(CaO^(*)+Na_(2)O)-K_(2)O and CIA vs.SiO_(2)plots that imply intense weathering in the source area.The obtained high CIA values(>80)indicates a steady-state of weathering under a warm/humid climate as confirmed by the SiO_(2)vs.Al_(2)O_(3)+K_(2)O+Na_(2)O plot.High average SiO_(2)(75.41wt%)with K_(2)O/Na_(2)O ratio>1(15.63),low Fe_(2)O_(3)(1.27wt%),Al_(2)O_(3)(15.82wt%)and TiO_(2)(0.46)suggest passive margin tectonic setting.This is supported by enrichedΣREE(209.64 ppm),ΣLREE(195.78),LREE/HREE(27.78)and negative Eu/Eu^(*)(0.68),plots of log(K_(2)O/Na_(2)O)vs.SiO_(2)and SiO_(2)/Al_(2)O_(3)vs.K_(2)O/Na_(2)O.Major elements discriminant-function multi-dimensional diagram,DF1(arcrift-col)vs.DF2(arc-rift-col),for high-silica sediments revealed a continental rift tectonic setting.Thus,the Patti Formation sandstone underwent a high degree of weathering under a humid climatic condition within a continental rift tectonic setting.展开更多
Human settlement and agricultural development are closely linked to local geomorphological and climatic environments.However,the variation in agricultural systems in different environmental and prehistoric contexts re...Human settlement and agricultural development are closely linked to local geomorphological and climatic environments.However,the variation in agricultural systems in different environmental and prehistoric contexts remains unknown.We report new archaeobotanical and radiocarbon dates from 34 Neolithic and Bronze Age sites in the Hutuo River Valley(HTRV)in north-central China and compare them with updated archaeobotanical studies in the Sushui River Valley(SSRV)and Henan Province(HNP),to explore the similarities and differences of agricultural patterns under different geomorphologic and climatic environments in north-central China.Our results reveal that humans consistently cultivated foxtail and broomcorn millet in the HTRV from the Miaodigou(6000–5700 cal.a BP)to the Shang-Zhou(3600–2256 cal.a BP)period,despite the introduction of wheat and barley into the area around 4000 a BP.Climate conditions and hilly landforms in the HTRV,SSRV and some parts of the HNP led people to develop foxtail and broomcorn millet dry land farming practices between 7000 and 3000 a BP.Alternatively,in other areas of the HNP,the climate conditions and alluvial plains enabled people to develop a mixed agriculture of millets,soybeans,and rice from 7000 to 4000 a BP,with the addition of wheat between 4000 and 3000 a BP.Farmers’different agricultural technologies and interactions with foreign cultures may have also influenced the formation of different agricultural patterns in the three regions between 7000 and 3000 a BP.Population growth during 7000–3000 a BP can explain the overall propensity of the higher-yield foxtail millet rather than broomcorn millet as the main cultivated crop.In the HTRV,however,higher proportions of broomcorn millet(as compared to the SSRV and HNP),may reflect the greater drought and heat tolerance of broomcorn millet,representing an adaptive agricultural strategy in the river valley.展开更多
The climate condition of a wind farm has a significant influence on the reliability of wind turbines. The climate condition varies with season in a year and hence the reliability changes in a complex way. The purpose ...The climate condition of a wind farm has a significant influence on the reliability of wind turbines. The climate condition varies with season in a year and hence the reliability changes in a complex way. The purpose of this paper is to model the effect of climate condition on field reliability of wind turbines. The reliability is measured by monthly-averaged mean time between failures(MTBF), and the climate conditions are described by variables of monthly-averaged temperature, relative humidity, rainfall and wind speed. Referring to the physicsof-failure models in accelerated life testing(ALT), we develop a quantitative relation between the MTBF and the climate variables. For a set of field data, the model parameters are estimated by regression, and the insignificant variables are gradually deleted based on the P-value of the regression coefficients. The resulting model is useful for maintenance workload forecasting and preventive maintenance planning, and has a potential to be used in online failure prediction.展开更多
Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelo...Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelopes.This work investigated the influence of the materials’hygric properties on the hygrothermal perfor-mance of a typical ITICS in different climate conditions in China.Two base wall materials,the traditional concrete and a new type aerated concrete,were tested and compared for their hygric properties firstly.The influence of the hygroscopicity of exterior plasters,the permeability of insulation materials and the climate conditions were then analyzed with WUFI simulations.The hygrothermal performance was evaluated with consideration of the total water content(TWC)of the walls and the moisture flux strength,the relative humidity(RH)and the mould growth risk at the interface between the base wall and the insulation layer(B-I interface).The numerical analysis implies that the TWC of internal insulated walls depends mainly on the hygroscopicity of exterior plaster and the wind-driven rain intensity.The upper limits for the water absorption coefficient of exterior plasters used in Bei-jing,Shanghai and Fuzhou are 1e-9,1e-10,1e-10 m^(2)/s respectively.When such limits are guaranteed,a vapour tight system created by using insulation materials with a large vapour resistance factor or adding a vapour barrier can improve the hygrothermal performance of ITICS,especially for concrete walls in cold climate.展开更多
文摘Climate warming has made the planting area of Hami melon expand northward to Barry Bakai Town,Altay City,near 47° N. Climate events often induce the occurrence of pests and diseases in crops,affecting the steady production of Hami melon. In 2013,pests and diseases occurred seriously,resulting in low yield and poor quality of Hami melon. Based on the production survey data of Hami melon in recent20 years,the interaction of various meteorological factors in different time and different intervals of various factors was analyzed in this paper to explore the characteristics of the meteorological factors that cause diseases and influence the quality of Hami melon.
文摘Based on temperature,precipitation and sunshine data at Longhui National Station during 1981-2021,temperature at 22 regional stations during 2011-2021,and lily planting information of Longya Lily Base,the feasibility of meteorological conditions for the growth of Lilium brownii var.viridulum was analyzed.The results showed that in general,the climatic conditions in Longhui were suitable for planting L.brownii var.viridulum.Among them,the south hilly area was the most suitable climate area,and the north mountain area was the suitable climate area,and the northwest mountain area was the more suitable climate area.It should sufficiently use the climatic conditions of Longhui,do a good job in meteorological service of L.brownii var.viridulum,and provide favorable meteorological guarantee for farmers,to reduce the impact of adverse meteorological conditions on L.brownii var.viridulum,and improve the economic benefits of lily production.
文摘This work focuses on the performance comparison of monocrystalline and polycrystalline Si solar photovoltaic(SPV)modules under tropical wet and dry climatic conditions in east-central India(21.16°N 81.65°E,Raipur,Chhattisgarh).This study would help to select the SPV module for system installation in the east-central part of the country.For comparative analysis,we used performance ratio(PR)and efficiency as figures of merit.The plane-of-array(POA)irradiance was used to determine the efficiency of the modules.The decomposition and transposition models calculated the POA values from the measured global horizontal irradiance.The data were analysed systematically for 6 months in the non-rainy season,from October 2020 to March 2021.Special attention was given to solar irradiance,ambient temperature and module temperature-the parameters that affect the performance of PV modules.The month of October showed the highest variation in irradiance and temperature.The highest average module temperatures(51-52℃)were observed in October-November,while the lowest average module temperatures(34℃ for mono-Si and 36℃ for poly-Si)were observed in December.The highest value of average monthly POA irradiance(568 W/m^(2))was observed in February and the lowest(483 W/m^(2))in December.The results showed that the monocrystalline SPV module performed better than the polycrystalline module under all weather conditions.The maximum observed values of mono-Si and poly-Si panel PRs were 0.89 and 0.86,respectively,in December.
文摘This paper is describing a detailed study of morphological structures and characteristics newborns thymus in different climatic and geographical conditions of Kara-Balta, Cholpon-Ata, and Bishkek in Kyrgyzstan. Anatomical structure research done on 26 thymuses of newborn corpses. Research results showed that a significant amount of thymuses consisted of lobes with very thin connective tissues between them. It is observed that the Hassall cells were usually located in the medulla part of the thymus after using the coloring by Van-Gieson’s stain visible clear elastic and collagen fibers. In addition, cell population dynamics in a unit of conditional area of cortical substance thymus lobes in newborns determined.
基金the Ph.D.Programs Foundation of Liaoning Province,China(Grant No.20061040).
文摘Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenhouses located at three cities in North,Northeast and Northwest China were predicted by CFD simulations of the greenhouse systems using typical meteorological data.The predicted temperatures based on the meteorological data in Shenyang are quite similar to the measured temperatures.The results also show that the external air temperatures and solar radiation fluxes play more important roles for the inside temperatures as indicated by the highest inner temperature in the morning on Feb.18 and from 10:00 to 14:00 on Feb.19 in Beijing and by the predicted temperatures inside the greenhouse being higher in Lanzhou than those in Shenyang and Beijing during most of the day.The average daily temperature inside the greenhouse in Lanzhou was nearly 3.5℃higher than that in Shenyang.Predicted air temperatures for various wall designs show that for single walls,the daily average interior temperatures in the aerated concrete wall greenhouse were higher than those in the brick wall and reinforced concrete wall greenhouses.However,the air temperature fluctuations were lower in the reinforced concrete wall greenhouse due to greater thermal storage capacity.The results also show that the temperatures in the layered wall greenhouses are quite similar,which coincides with the experimental results。
文摘This article deals with the biochemical characteristics of varieties of Saint Mary’s Thistle such as Panacea, Debut and Samaryanka. Based on the studies, it was found that the highest oil content was found in the species Debut (26%). <span style="font-family:Verdana;">The lowest oil content was observed in the variety </span><span style="font-family:Verdana;">Samaryanka</span><span style="font-family:Verdana;"> (19%). The highest protein content and the sum of total amino acids in the seeds of St. Mary’s Thistle varieties were found in the variety Debut (131.1), and the lowest indication was observed in the species Samaryanka (79.2). By the number of replaceable amino acids existing in the seeds of the species of St. Mary’s Thistle, it was found in the Varieties Debut (126.3), and the lowest indication was observed in the variety Samaryanka (112). Based on the results of studies and the noted biochemical characteristics and varietal differences of the St. Mary’s Thistle, the possibility and expediency of expanding the crops of this species in the soil and climatic conditions of the Khorezm region are suggested. The research was conducted 2017-2019 y.</span>
基金Supported by Policy Guidance Item of Science and Technology Development Plan in Shandong Province(2010YD17006)
文摘[ Objective]The research aimed to study influences of the climate conditions on organic agriculture and defense countermeasures of the meteorological disasters in Boshan District of Shandong. [ Method ] From climate resources, relationships between meteorological conditions (tem- perature, water and sunshine, etc. ) and growth of the organic crops in Boshan District of Shandong were analyzed. 5-year development plan was put forward. Influences of the main meteorological disasters in growth process of the organic crops were analyzed. Moreover, corresponding de- fense countermeasures were put forward. [ Result] Due to monsoon influence in Boshan, rain and heat were in same season. Sunshine, heat and water coordinated well, and effectivity of the agricultural climate resources was higher. Qualities of the soil and water were good. Vegetation was complete. These conditions were all favorable for developing organic agricultural region. But the precipitation variability was big, which limited effec- tive utilizations of the sunshine and heat resources at different degrees. Meanwhile, in organic crops growth season when sunshine, heat and water were sufficient, meteorological disasters happened frequently. [ Conclusion] We should accelerate construction of the small water conservancy facil- ities, making rainstorm and flood as resources, and realizing timely watering. In addition, we ought to accelerate construction of the industrialized organic a clriculture to improve agricultural benefit.
基金the National Natural Science Foundation of China(No.41971076No.42171128)the Heilongjiang Provincial Department of Science and Technology(GA21A501)。
文摘Two-phase closed thermosyphons(TPCTs)are widely used in infrastructure constructions in permafrost regions.Due to different climatic conditions,the effectiveness of TPCT will also be different,especially in the extremely cold region of the Da Xing'anling Mountains.In this study,a series of three-dimensional finite element TPCT embankment models were established based on the ZhanglingMohe highway TPCT test section in Da Xing'anling Mountains,and the thermal characteristics and the cooling effect of the TPCTs were analyzed.The results indicated that the TPCTs installed in the northeastern high-latitude regions is effective in cooling and stabilizing the embankment.The working cycle of the TPCTs is nearly 7 months,and the cooling range of the TPCTs can reach 3 m in this region.However,due to the extremely low temperature,the TPCT generates a large radial gradient in the permafrost layer.Meanwhile,by changing the climate conditions,the same type of TPCT embankment located in the Da Xing'anling Mountains,the Xiao Xing'anling Mountains,and the Qinghai-Tibet Plateau permafrost regions were simulated.Based on the comparison of the climate differences between the Qinghai-Tibet Plateau and Northeast China,the differences in the effectiveness of TPCTs were studied.Finally,the limitations of using existing TPCTs in high-latitude permafrost regions of China were discussed and the potential improvements of the TPCT in cold regions were presented.
文摘AIM:To study the normal aerobic conjunctival flora in lower to mid Himalayan region of Shimla Hills.METHODS:Samples from normal conjunctiva of 200 individuals above the age of 13 years who visited Indira Gandhi Medical College Hospital Shimla for refraction or cataract surgery were taken by anaesthetising the conjunctival sac with sterile 4% Xylocaine solution.Samples were obtained by gently rubbing lower fornix with a sterile cotton wool swab moistened with normal saline and keeping the eye lids wide apart to avoid contamination from lid margins.It was immediately inoculated in Brain Heart infusion and subjected to standard aerobic culture and identification techniques.RESULTS:Totally,72 eyes(36%) conjunctival sacs were sterile.Predominant aerobes isolated were Staphylococcus spp.in 120(60%) followed by Haemophilus in 16(8%),diphtheroids in 10(5%),and Escherichia coli(E.coli) in 4(2%).A single aerobe was isolated from 98 eyes(49%) while 30 eyes(15%) yielded more than 1 aerobe.Staphylococcus epidermidis(S.epidermidis) was the most common bacterium,found alone in 58 eyes(29%) and in combination with another aerobe in 30 eyes(15%),followed by Staphylococcus aureus(S.aureus) in 18(9%) and 10 eyes(5%) respectively.CONCLUSION:S.epidermidis is the most common commensal organism followed by Haemophilus species.diphtheroids occupied the third position which otherwise are found more abundantly in literature.Pathogens like S.aureus,Staphylococcus citreus and E.coli were also found.Therefore,preoperative administration of topical broad spectrum antibiotics is extremely important in prophylaxis against ocular infection.The variation in microflora of normal conjunctiva in this part of world can be attributed to geographical,climatic and ethnic characteristics of the population under study.
基金funded by the National Natural Science Foundation of China (41271126)the Ph.D. Research Foundation of Guizhou Normal Universitythe Science and Technology Foundation of Guizhou Province (J[2014]2126)
文摘The mountainous forests in arid regions, being sensitive to climate change, are one of the key research topics related to the mechanism of interaction between climate and the terrestrial ecosystem. In this study, the spatial distribution of a mid-mountain forest and its environmental factors were investigated by using a combination of remote sensing technology, field survey, climate indices and soil nutrient analysis in the Sangong River watershed of the northern Tianshan Mountains. The forest (Picea schrenkiana) was distributed between 1,510 and 2,720 m asl. Tree height and diameter at breast height (DBH) exhibited a bi-modal pattern with increasing elevation, and rested at 2,450 and 2,250 m asl, respectively. The two maxima of DBH appeared at 2,000 and 2,550 m asl, and the taller trees were observed at 2,100 and 2,600 m asl. For the annual mean temperature, the difference was approximately 5.8℃ between the lowest and the highest limits of the forest, and the average decreasing rates per hundred meters were 0.4g℃ and 0.55℃ with increasing altitude between 1,500 and 2,000 m asl and above 2,000 m asl, respec- tively. The annual precipitation in the forest zone first increased and then decreased with the increase of altitude, and the maximum value was at 2,000 m asl. For per hundred meters, the annual precipitation increased with the rate of 31 mm between 1,500 and 2,000 m asl and decreased by 7.8 mm above 2,000 m asl. The SOM, TN and TP were high between 2,000 and 2,700 m asl and low at the lower and upper forest limits. The minimum CaCO3 con- centration, pH value and EC coincided with the maximum precipitation belt at 2,000 m asl. The SOM, TN and TP were high in the topsoil (0-10 cm) and differed significantly from the values observed in the deep soil layers (〉10 cm). The soil nutrients exhibited spatial heterogeneity and higher aggregation in the topsoil. In conclusion, soil and climate are closely related to each other, working synergistically to determine the development and spatial distribution of the mid-mountain forest in the study area. The order of the importance of environmental factors to forest development in this study is as follows: soil nutrients〉precipitation〉elevation〉temperature.
文摘To study the sensitivity of inter-subspecific hybrid rice to climatic conditions, the spikelet fertilized rate (SFR) of four types of rice including indica-japonica hybrid, intermediate hybrid, indica and japonica were analyzed during 2000-2004. The inter-subspecific hybrids showed lower SFR, and much higher fluctuation under various climatic conditions than indica and japonica rice, showing the inter-subspecific hybrids were sensitive to ecological conditions. Among 12 climatic factors, the key factor affecting rice SFR was temperature, with the most significant factor being the average temperature of the seven days around panicle flowering (T7). A regressive equation of SFR-temperature by T7, and a comprehensive synthetic model by four important temperature indices were put forward. The optimum temperature for inter-subspecific hybrids was estimated to be 26.1-26.6℃, and lower limit of safe temperature to be 22.5-23.3℃ for panicle flowering, showing higher by averagely 0.5℃ and 1.7℃, respectively, to be compared with indica and japonica rice. This suggested that inter-subspecific hybrids require proper climatic conditions. During panicle flowering, the suitable daily average temperature was 23.3-29.0℃, with the fittest one at 26.1-26.6℃. For an application example, optimum heading season for inter-subspecific hybrids in key rice growing areas in China was as same as common pure lines, while inferior limit for safe date of heading was about a ten-day period earlier than those of common pure lines.
文摘Water is a vital resource.It supports a multitude of industries,civilizations,and agriculture.However,climatic conditions impact water availability,particularly in desert areas where the temperature is high,and rain is scarce.Therefore,it is crucial to forecast water demand to provide it to sectors either on regular or emergency days.The study aims to develop an accurate model to forecast daily water demand under the impact of climatic conditions.This forecasting is known as a multivariate time series because it uses both the historical data of water demand and climatic conditions to forecast the future.Focusing on the collected data of Jeddah city,Saudi Arabia in the period between 2004 and 2018,we develop a hybrid approach that uses Artificial Neural Networks(ANN)for forecasting and Particle Swarm Optimization algorithm(PSO)for tuning ANNs’hyperparameters.Based on the Root Mean Square Error(RMSE)metric,results show that the(PSO-ANN)is an accurate model for multivariate time series forecasting.Also,the first day is the most difficult day for prediction(highest error rate),while the second day is the easiest to predict(lowest error rate).Finally,correlation analysis shows that the dew point is the most climatic factor affecting water demand.
基金Razi University(Kermanshah-Iran) authorities for the financial support during the field work
文摘Study of the climate variability in the past and present, and correlating those with changes in the distribution range of species has attracted considerable research interest. The genus Ablepharus consists of 10 recognized species, of which A. bivittatus, A. grayanus and A. pannonicus are documented from Iran. In the present study, we modeled with MaxEnt the potential distribution areas and determined the suitable habitats in past (mid-Holocene [MH], and the Last Interglacial [LIG]) and their current distribution for two species of snake-eyed skinks (A. grayanus and A. pannonicus) separately. Models of the species indicated good fit by the average high area under the curve (AUC) values (A. grayanus = 0.929 4- 0.087 and A. pannonicus = 0.979 4- 0.007). Precipitation of the driest quarter of the year, mean temperature of the coldest quarter of the year, and precipitation of the driest month variables made important contributions to A. grayanus. Two important climate variables contributed importantly to A. pannonicus; temperature seasonality, and mean temperature of the wettest quarter of the year, and one topographic variable, slope. We conclude that these variables form a natural barrier for species dispersal. The MH and the LGM models indicated a larger suitable area than the current distribution.
基金supported financially by the National Natural Science Foundation of China(Grant No.51978449)was conducted based on the results of“the 13th Five Year”National Science and Technology Ma-jor Project of China(Grant No.2018YFC0704500)National Natural Science Foundation of China(Grant No.51378336).
文摘Currently,climatic design conditions are usually selected according to the frequency of climatic parameters them-selves,which method cannot reflect the indoor thermal environment risk level of the building in design.In this regard,the research proposes to construct the correlation between climatic design conditions and indoor thermal environment risk level,and explore the effect of uncertainty in building thermal performance on this correlation from the perspective of probability,thus realizing the process of selecting the climatic design conditions based on the requirement for indoor thermal environment risk level.Taking Guangzhou in China as an example,the new process of determining climatic design conditions is realized.On this basis,the difference between the traditional method and the present research method is compared.In the Chinese norm method,the indoor thermal environ-ment risk level of the building is between 0 and 0.03%when the climatic design conditions are selected with 0.57%cumulative frequency of occurrence;in the research method,the indoor thermal environment risk level of the building is between 0.2%and 0.6%when the climatic design conditions are selected with 0.57%indoor thermal environment risk level and 100%confidence level.The results indicate that the research method can meet the designer’s expectation for indoor thermal environment risk level in design more directly and accurately.
基金the National Key Research&Development Program of China(2016YFD0200102 and 2018YFD0201001).
文摘Microbes are decomposers of crop residues,and climatic factors and residue composition are known to influence microbial growth and community composition,which in turn regulate residue decomposition.However,the succession of the bacterial community during residue decomposition in Northeast China is not well understood.To clarify the property of bacterial community succession and the corresponding factors regulating this succession,bags containing maize residue were buried in soil in Northeast China in October,and then at different intervals over the next 2 years,samples were analyzed for residue mass and bacterial community composition.After residue burial in the soil,the cumulative residue mass loss rates were 18,69,and 77%after 5,12,and 24 months,respectively.The release of residue nitrogen,phosphorus,and carbon followed a similar pattern as mass loss,but 79%of residue potassium was released after only 1 month.The abundance,richness,and community diversity of bacteria in the residue increased rapidly and peaked after 9 or 20 months.Residue decomposition was mainly influenced by temperature and chemical composition in the early stage,and was influenced by chemical composition in the later stage.Phyla Actinobacteria,Bacteroidetes,and Firmicutes dominated the bacterial community composition in residue in the early stage,and the abundances of phyla Chloroflexi,Acidobacteria,and Saccharibacteria gradually increased in the later stage of decomposition.In conclusion,maize residue decomposition in soil was greatly influenced by temperature and residue composition in Northeast China,and the bacterial community shifted from dominance of copiotrophic populations in the early stage to an increase in oligotrophic populations in the later stage.
基金This work is supported by the National Natural Science Foundation of China(Grant No.42041004 and 41991231)the“Innovation Star”Project for Outstanding Postgraduates of Gansu Province(Grant No.2022CXZX-107)the Central Universities(Grant No.lzujbky-2019-kb30).
文摘Under global warming, seasonal snow takes faster melting rate than before, which greatly changes the hydro-logical cycle. In this study, by targeting three typical seasonal snow-covered land types (i.e., open shrubland,evergreen needleleaf forest and mixed forest) in the Northern Hemisphere, the start of growing season (SGS) hasbeen found obviously advanced in the past years, greatly contributed by the faster melting rate of seasonal snow.It is manifested that significantly positive correlation has been found between SGS and May snow depth for openshrubs, March and April snow depth for evergreen needleleaf forests and March snow depth for mixed forests.However, such close association is not appeared in all the climate conditions of same vegetation. In the future,as the rate of melting snow becomes faster in the high emission of greenhouse gasses than the current situation,continuously advanced SGS will accelerate the change of vegetation distribution in the Northern Hemisphere.These findings offer insights into understanding the effect from seasonal snow on vegetation and promote thesustainable utilization of regional vegetation in the Northern Hemisphere.
文摘Sandstones sampled from Patti Formation,Southern Bida Basin,were studied geochemically using Inductively Coupled Plasma Atomic Emission Spectrophotometer(ICP-AES)and an Inductively Coupled Plasma Mass Spectrometry(ICP-MS)technique to evaluate their weathering and tectonic setting as well as to deduce the paleo-climatic conditions that existed during their deposition.Geochemically,SiO_(2)range from 73.9%to 86.2%,Al_(2)O_(3)(6.7%~17.1%),Fe_(2)O_(3)(1.1%~1.9%),K_(2)O(0.1%~0.7%)while MgO,CaO,Na_(2)O,P_(2)O_(5),MnO and TiO_(2)were<1%.Enriched in Ba(Av.622.94),Sr(Av.153.63),Rb(Av.55.08)and Zr(Av.51.86)relatively similar in composition to UCC.High SiO_(2)but low other major oxides signify high mobility during processes of weathering.This was confirmed by high value(>80%)for indices like chemical index of alteration,chemical index of weathering,plagioclase index of alteration,mineralogical index of alteration and relatively lower values for weathering index of parker,recently used alpha indices(α^(Al)_(E))of sodium(326.17α^(Al)_(Na)<344.40),magnesium(100.54α^(Al)_(mg)<398.55),calcium(12.07α^(Al)_(Ca)<198.99),potassium(4.43α^(Al)_(K)<64.33),strontium(0.84α^(Al)_(E)<21.40),barium(0.45α^(Al)_(Ba)<10.52)and rubidium(0.0008α^(Al)_(Rb)<0.06),supported by AI_(2)O_(3)-(CaO^(*)+Na_(2)O)-K_(2)O and CIA vs.SiO_(2)plots that imply intense weathering in the source area.The obtained high CIA values(>80)indicates a steady-state of weathering under a warm/humid climate as confirmed by the SiO_(2)vs.Al_(2)O_(3)+K_(2)O+Na_(2)O plot.High average SiO_(2)(75.41wt%)with K_(2)O/Na_(2)O ratio>1(15.63),low Fe_(2)O_(3)(1.27wt%),Al_(2)O_(3)(15.82wt%)and TiO_(2)(0.46)suggest passive margin tectonic setting.This is supported by enrichedΣREE(209.64 ppm),ΣLREE(195.78),LREE/HREE(27.78)and negative Eu/Eu^(*)(0.68),plots of log(K_(2)O/Na_(2)O)vs.SiO_(2)and SiO_(2)/Al_(2)O_(3)vs.K_(2)O/Na_(2)O.Major elements discriminant-function multi-dimensional diagram,DF1(arcrift-col)vs.DF2(arc-rift-col),for high-silica sediments revealed a continental rift tectonic setting.Thus,the Patti Formation sandstone underwent a high degree of weathering under a humid climatic condition within a continental rift tectonic setting.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41825001, 41871076, 4210011192 and 41501216)the Open Foundation of MOE Key Laboratory of Western China’s Environmental Systems, Lanzhou University+3 种基金the Fundamental Research Funds for the Central Universities (Grant Nos. lzujbky-2021-kb01, 2019jbkyzy014 and lzujbky-2018-43)the Fundamental Research Funds for the Central Universities of Nanjing Agricultural University (Grant Nos. SKYC2021011 and KYYJ202111)Open Fund Project of the State Key Laboratory of Loess and Quaternary Geology (Grant No. SKLLQG2015)General Project of Philosophy and Social Science Research in Universities in 2021 (Grant No. 2021SJA0052)
文摘Human settlement and agricultural development are closely linked to local geomorphological and climatic environments.However,the variation in agricultural systems in different environmental and prehistoric contexts remains unknown.We report new archaeobotanical and radiocarbon dates from 34 Neolithic and Bronze Age sites in the Hutuo River Valley(HTRV)in north-central China and compare them with updated archaeobotanical studies in the Sushui River Valley(SSRV)and Henan Province(HNP),to explore the similarities and differences of agricultural patterns under different geomorphologic and climatic environments in north-central China.Our results reveal that humans consistently cultivated foxtail and broomcorn millet in the HTRV from the Miaodigou(6000–5700 cal.a BP)to the Shang-Zhou(3600–2256 cal.a BP)period,despite the introduction of wheat and barley into the area around 4000 a BP.Climate conditions and hilly landforms in the HTRV,SSRV and some parts of the HNP led people to develop foxtail and broomcorn millet dry land farming practices between 7000 and 3000 a BP.Alternatively,in other areas of the HNP,the climate conditions and alluvial plains enabled people to develop a mixed agriculture of millets,soybeans,and rice from 7000 to 4000 a BP,with the addition of wheat between 4000 and 3000 a BP.Farmers’different agricultural technologies and interactions with foreign cultures may have also influenced the formation of different agricultural patterns in the three regions between 7000 and 3000 a BP.Population growth during 7000–3000 a BP can explain the overall propensity of the higher-yield foxtail millet rather than broomcorn millet as the main cultivated crop.In the HTRV,however,higher proportions of broomcorn millet(as compared to the SSRV and HNP),may reflect the greater drought and heat tolerance of broomcorn millet,representing an adaptive agricultural strategy in the river valley.
基金the National Natural Science Foundation of China(No.71371035)
文摘The climate condition of a wind farm has a significant influence on the reliability of wind turbines. The climate condition varies with season in a year and hence the reliability changes in a complex way. The purpose of this paper is to model the effect of climate condition on field reliability of wind turbines. The reliability is measured by monthly-averaged mean time between failures(MTBF), and the climate conditions are described by variables of monthly-averaged temperature, relative humidity, rainfall and wind speed. Referring to the physicsof-failure models in accelerated life testing(ALT), we develop a quantitative relation between the MTBF and the climate variables. For a set of field data, the model parameters are estimated by regression, and the insignificant variables are gradually deleted based on the P-value of the regression coefficients. The resulting model is useful for maintenance workload forecasting and preventive maintenance planning, and has a potential to be used in online failure prediction.
基金This research was funded by National Key R&D Program of China(2017YFC0702800),which is gratefully acknowledged.
文摘Internal thermal insulation composite system(ITICS)can be an important measure for the energy-saving retrofitting of buildings.However,ITICS may cause harmful effects on the hygrothermal performance of building envelopes.This work investigated the influence of the materials’hygric properties on the hygrothermal perfor-mance of a typical ITICS in different climate conditions in China.Two base wall materials,the traditional concrete and a new type aerated concrete,were tested and compared for their hygric properties firstly.The influence of the hygroscopicity of exterior plasters,the permeability of insulation materials and the climate conditions were then analyzed with WUFI simulations.The hygrothermal performance was evaluated with consideration of the total water content(TWC)of the walls and the moisture flux strength,the relative humidity(RH)and the mould growth risk at the interface between the base wall and the insulation layer(B-I interface).The numerical analysis implies that the TWC of internal insulated walls depends mainly on the hygroscopicity of exterior plaster and the wind-driven rain intensity.The upper limits for the water absorption coefficient of exterior plasters used in Bei-jing,Shanghai and Fuzhou are 1e-9,1e-10,1e-10 m^(2)/s respectively.When such limits are guaranteed,a vapour tight system created by using insulation materials with a large vapour resistance factor or adding a vapour barrier can improve the hygrothermal performance of ITICS,especially for concrete walls in cold climate.