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- Abstract：Haploids induced from 22 inbred lines were pollinated with normal diploid pollen to investigate the genetic inheritance of haploid female fertility (HFF).The average haploid female fertility rate (HFFR)was about 89.54%,and the range was from 73.56% to 99.18%.The average kernel number (AKN) was 15.40 ranging from 2.67 to 59.82.The heritability for HFFR and AKN were 0.67 and 0.86,respectively.It is found that B73 had the best HFF 99.18% and the AKN was 59.82.It is also found that genetic background was the main factor effecting haploid male fertility.No significant correlation was found between haploid male fertility (HMF) and HFF,which reveals that the process of HMF and HFF may have separate processes.Keywords：maize haploid;inbred line;spontaneous doubling;haploid female fertility;haploid male fertility0|7|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to find effective agronomic measures,which could reduce the lodging rate of quinoa.A field experiment was conducted to compare the effects of five chemical control agents (Paclobutrazol,JinDele,Chlormequat,Mepiquat chloride and Ethephon) and topping on the growth and yield of quinoa plants,the results showed that:1) Compared with the normal cultivated quinoa plant(CK),spraying paclobutrazol and chlormequat could effectively reduce the plant height and promote chlorophyll content of plant leaves;2) Spraying chlormequat and topping measures rapidly increased the leaf area per plant of quinoa,which were 18.2% and 9.7% higher than that of control,respectively.The treatment of mepiquat chloride inhibiteded the growth of plant leaf area,which was 12.11% less than that of control.Chemical control obviously improved photosynthetic rate and the water use efficiency of the leaves,among which chlormequat was the best;3) Topping increased the number of primary branches,but lateral lodging rate was higher.Chlormequat significantly reduced the number of primary branches and the rate of lateral lodging.Spraying chemical control agent could promote plant stem thickening,and Jin Dele treatment effect was obvious;4) The chemical control treatment could promote the grain weight and yield significantly.The yield of chlormequat treatment was the highest,and was 114.7% higher than that of control.Spraying chlormequat,paclobutrazol and topping measures significantly improved the thousand kernel weight of quinoa,which were conducive to yield.In conclusion,chlormequat significantly control plant height reduced the rate of side branch of quinoa,promoted plant growth and improved photosynthetic characteristics of leaves,which was also conducive to the formation the yield.It can be used as a suitable chemical resistance control mearsures for high yield cultivation of quinoa.Keywords：quinoa;chemical control;lodging;yield0|8|6<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The objectives of this study were to explore the response of different sorghum parental lines to drought stress,and screen a set of suitable indexes for identifying drought resistance in parental lines with high drought resistance.A total of 41 sorghum materials including 15 B-lines,18 R-lines,and 8 hybrids germinated in Petri dishes in artificial climate chamber were taken as study materials.PEG-6000(-0.3 MPa) was used to simulate the typical drought stress environment with distilled water as control.Eight parameters including germination rate,germination potential,bud length,root length,bud dry weight,root dry weight,remaining material dry weight,and germination drought resistance index were measured.The results showed that the average subordinate function values of B-lines and R-lines were significantly lower than that of hybrids and no significantly differences existed between B-lines and R-lines.All materials were clustered into five groups:Two materials were resistant to drought,e.g.L116;Eighteen materials were relative resistance to drought,e.g.Ms18B;Nine materials had medium resistance,e.g.Ms19B;Eight materials were relatively sensitive to drought,e.g.L5172;Four materials were sensitive to drought,e.g.2055B.The germination drought resistance index,root length and the remaining materials dry weight had the largest loading on germination factor,root growing factor,and biomass transformation factor,respectively.PEG-6000 with -0.3 MPa water potential was suitable for drought resistance screening of sorghum parental lines.The ability of drought resistance of sorghum parental lines was significantly lower than that of hybrids,which was not significantly different between B-lines and R-lines.B-line L116 and R-line Ms27B had high drought resistance.In conclusion,the germination drought resistance index,root length,remaining material dry weight were recommended as the suitable indexes for identifying drought resistance of sorghum parental lines at germination.Keywords：sorghum;parental lines;germination stage;drought resistance;subordinative function analysis;cluster analysis;factor analysis1|10|12<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To optimize the technology of drip irrigation,which is applied to winter wheat planted area in north Xinjiang,and investigate the effects of different drip irrigation amount on yield formation and water consumption characteristic of winter wheat,a field experiment with 8 different drip irrigation amounts including 0 (CK),900 (W1),1 800 (W2),2 700 (W3),3 600 (W4),4 500 (W5),5 400 (W6) and 6 300 m3/hm2 (W7) was carried out in a randomized block design experimental from 2013 to 2015.The leaf area index (LAI),SPAD value,photosynthetic character,dry matter accumulation of per stem,yield and water consumption characteristic were recorded and analyzed from heading stage to maturity stage of winter wheat.The results showed that:LAI in all of treatments showed a trend of single peak,and reached the maximum at booting stage.With the value of 6.25,W5 was the highest among treatments;The peak of SPAD was delayed with the increasing of drip irrigation.The net photosynthetic rate (Pn),transpiration rate (Tr),stomatal conductance (Gs) of leaf and the maximum increase rate of each plant dry matter were all increased first and then decreased with the increasing of irrigation amount,and all of those were highest in W5.Yield and water use efficiency (WUE) also showed an increasing trend first and then decree singtrend with increasing of the irrigation volume.Yield was highest in W5 treatment,while the WUE was highest in W4.In conclusion,with appropriate irrigation amount,to obtain high production and efficiency,it is suggested that 3 600-4 500 m3/hm2 for winter wheat planted in local conditions.Keywords：winter wheat;drip irrigation amount;photosynthetic characteristic;dry matter accumulation;yield;water consumption characteristic0|9|6<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Oligo-N-acetyl-D-aminoglucuronic acid iodide (OA-I) is a novel chitosan oligosaccharide derivatives agricultural preparation and a stable complex formed by anionic oligosuronic acid with iodine.The inhibition of Tobacco mosaic virus (TMV) and its effects on the growth and physiological characteristics of tomato were studied in order to provide basis for further development and application.Using tomato varieties,L402,Beilute and Fenduoli,as test materials,3% amino oligosaccharides and 50% Pythium L powder as contrasts,the effect of OA-I on TMV,the physiological characteristics of tomato and the content of Iindole acetic acid(IAA),Gibberellin (GA) and total chlorophyll in tomato seedling were studied by indoor bioassay experiments.The results showed that the control effect of OA-I on TMV was quick and lasting,which was increased from 45.08% to 74.48% after TMV inoculation at 17 d,and maintained above 80% after 21-35 d.The EC50 value of OA-I on TMV was 15.62 mg/L and higher than that of 3% amino oligosaccharide (EC50 value was 17.38 mg/L).Active ingredient 300.0 mg/L of OA-I was optimal to inhibit TMV activity;OA-I was safe for 3 tomato varieties at 300 mg/L-1200 mg/L dose,and no symptoms of phytotoxicity were observed.Compared with CK,3% amino oligosaccharide and 50% Pythium L powder,OA-I significantly improved the plant height of tomato seedlings,the IAA,GA and total chlorophyll contends in tomato leaves.In conclusion,OA-I has good prospects for development and utilization.Keywords：oligoglucuronic acids-iodine;Tobacco mosaic virus;chitooligosaccharide derivatives;inhibitory activity0|9|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To clarify the diversity and relationship of Rubus biflorus Buch,the genetic and phytochemical diversities of 7 populations of Rubus biflorus Buch were investigated using ISSR and HS-SPME/GC-MS.The results showed that:Among102 clear amplified bands obtained by 11 pairs primers,99 were polymorphic.The number of polymorphic bands accounted for 96.07% of total bands,the Shannon index of diversity I was 0.490 9,indicating that Rubus biflorus Buch had abundant genetic diversity.The coefficient of gene differentiation (GST,0.365 2) and AMOVA analysis revealed that most genetic diversities were distributed within populations (71.28%).The estimate of gene flow based on GST was 1.241 1.28 aromatic compounds were detected among 45 Rubus biflorus Buch in total.The Euclidean distance among the seven populations varied from 0.028 6-0.144 6.The Mantel test showed that there was no significant correlation between the genetic distance and Euclidean distance (r=-0.153 2,P=0.676 0).Principal component analysis was used to evaluate the 28 aromatic components.The results indicated that the former 4 principal components accounted for 74.20% of the cumulative contribution value.In conclusion,PCA could simplify the complicate original data to principal components,which reflected the aroma constitution preferably.This study showed that there existed a rich genetic diversity providing references for further research and utilization of Rubus biflorus Buch resources.0|7|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Alfalfa root rot has caused serious economic losses in alfalfa production.It has become an important factor restricting the sustainable development of alfalfa industry.To determine the biological characteristics of Fusarium caused alfalfa root rot in Hebei Province,China,ten Fusarium strains isolated from the diseased alfalfa samples in different years including D19-2 (F.oxysporum),S45 (F.proliferatum),Q1 (F.solani),QD13-2 (F.oxysporum),QZ3 (F.equiseti),N12-1 (F.acuminatum),N1-2 (F.redolens),B1-6-3 (F.oxysporum), B2-1-2 (F.tricinctum) and B1-7-5 (F.proliferatum),which were used to investigate the effects of media,temperature conditions and pH of the media on the colony diameter and sporulation of these strains.The effects of light conditions,carbon sources and nitrogen sources on the colony diameter and sporulation of Fusarium strains QD13-2,QZ3,N12-1,N1-2,B1-6-3,B2-1-2 and B1-7-5 were also investigated.And the lethal temperatures for mycelial growth of Fusarium strains QD13-2,QZ3,N12-1 and N1-2 were determined.The results demonstrated that for the mycelial growth of the strains D19-2,S45 and Q1,the optimum media were PDA and Czapek,the optimum temperatures were 26-28℃,and the optimum pH values were 7-8.The results showed that the conditions with temperature of 15-28℃ and the pH of 5-11 under the full darkness or the alternation of illumination and darkness with soluble starch as the best carbon source and glycine as the best nitrogen source were suitable for the mycelial growth of the strains QD13-2,QZ3,N12-1,N1-2,B1-6-3,B2-1-2 and B1-7-5,and that the mycelial growth of the seven Fusarium strains was inhibited when ammonium chloride was used as the nitrogen source.The lethal temperatures for the mycelial growth of the strains QD13-2,QZ3,N12-1 and N1-2 were 65,51,48 and 63℃,respectively.The results of this study are of great significance for understanding the occurrence rules of alfalfa root rot and making the integrated control strategies and measures.Keywords：alfalfa;root rot;Fusarium;biological characteristics0|8|15<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the effects of nutrients-enriched Artemia nauplii on the growth and survival rate of aquacultural seedlings during cultivation,Artemia is taken as study object in this study.The body length of Artemia,contents of crude proteins as well as EPA and DHA are determined or assayed by microscopy,Kjeldahl determination and gas chromatography methods during the development following cysts hatching.Three species of microalgae,Dicrateria zhanjiangensis,Platymonas subcordiformis and Chlorella pyenoidosa,are used to feed Artemia from 3 instar stage.The body length of Artemia,contents of crude proteins as well as EPA and DHA at 24 h and 48 h following feeding tests are determined to evaluate the effects.The results show that:The EPA content of Artemia is reduced at 120 h following hatching.All the 3 species of microalgae are able to promote growth of Artemia rather than increase the contents of proteins.The enrichment with microalgae for 48 h is capable of elevating the content of EPA in Artemia.The results suggest that the enrichment of microalgae is beneficial for the Artemia growth and enhancement of EPA contents.Of three microalgae species tested,P.subcordiformis displays the best performance.Keywords：Artemia;microalgae;nutrient enrichment;growth0|7|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to study the droplet morphological characteristics of cow during the spray cooling process,and the relationship between spread coefficient and droplet spraying velocity and contact angle in the process of water drop hitting the wall,a three-dimensional numerical simulation of the collision between a single droplet and the solid wall was carried out by using the CLSVOF numerical simulation method.First of all,based on the experimental test reported by Yokoi,this study verified the accuracy of the numerical model in this study.Then,based on the experimental data,a numerical model was established.Combined with Weber number (We),Reynolds number (Re) and coefficient K,the numerical model is validated.Morphological changes during the process of water droplets hitting solid wall were studied at 2 droplet diameter of 0.5 and 0.8 mm:Firstly,the velocity of 1,2 and 3 m/s,the average contact angle of 120° respectively;Secondly,the contact angles of 90°,120° and 140°,the velocity of 1 m/s respectively.The results showed that:With the increase of droplet diameter and impact velocity,there were 4 typical forms of motion after the droplet hitting wall including oscillation,bounce,breaking,splashing;With the increase of water droplet velocity,the spreading velocity of water droplets accelerated,the maximum spreading diameter and spread coefficient increased at the same time;With the increase of contact angle,the maximum spreading diameter of water droplets decreased and the maximum spreading coefficient decreased.Keywords：CLSVOF;droplet morphology;dairy sprinkler;contact angle;water droplet velocity1|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To explore new approaches on kidney-bean protein processing,acetylation was utilized to modify kidney bean protein isolate (KPI).The changes of exposed sulfhydryl,free sulfhydryl,disulfide bond and surface hydrophobicity in the process of acetylation were analyzed and then the effects of acetylation on gel properties of KPI were discussed.The results showed that:1) When the ratio of anhydride to protein was 0.2 g/g and acylation degree of protein reached 89%,which means that the modification process was almost completed.Compared with the unmodified KPI,the solubility of modified protein isolate was much higher under neutral condition (pH6-8).2) With the increase of acetylation extent,the total free sulfhydryl molality decreased,the surface sulfhydryl molality and disulfide bond molality gradually increased while surface hydrophobicity displayed the tendency declining at the beginning and rising up in late.Compared with the unmodified KPI,the surface sulfhydryl molality and surface hydrophobicity of modified protein were significant increased,which significantly enhanced the molecular interaction in gel formation process and thus improved the hardness,springiness and cohesiveness of the protein gel.Keywords：kidney bean protein isolation;acetylated modification;acetic anhydride;gel properties0|7|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Given that it is a tedious and high cost work to measure area,length,width and other parameters of crop using traditional methods and leaf area meter,a image method for calculating area,perimeter,length and width of apple leaf was proposed in this paper.Firstly,RGB (red,green,blue) image was convert into HIS (hue,intensity,saturation) color space.Secondly,Otsu method of segmentation was applied to implement binaryzation of H color channel.And finally,the perimeter,length and width of apple leaf were determined based on the distribution feature of boundary pixel coordinate of apple leaf and the apple leaf area was calculated by counting the number of apple leaf pixels.In order to prove the rationality of methods,the RMSE and R2 between the calculated and measured apple leaf area,leaf length and width was calculated and perimeter algorithm was test with the help of estimating the circumference of the different size coins.The results showed that RMSE and R2 for apple leaf area,leaf length and width were 0.58 cm2,0.46 cm,0.10 cm,0.99,0.93 and 0.97,respectively.And the calculated circumference of one yuan,fifty cents and ten cents of RMB was 7.68 cm,6.42 cm and 6.10 cm,respectively.The low values of RMSE and high values of R2 indicated that the result obtained by method of measurement of apple leaf area,leaf length and width were reliable.And the verification results with respect to method of measurement of apple leaf perimeter showed that there were little differences between calculated and true values.Keywords：segmentation of image;apple leaf;leaf area;perimeter;leaf length;leaf width4|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Aiming to establish leaf Gross Primary Productivity inversion model based on hyperspectral Vegetation Indices,the hyperspectral reflectance and light intensity (PARin) of rape and wheat leaves in the experimental field of Wuhan University in Hubei Province were taken as data sources.Seven vegetation indices were respectively multiplied by PARin to get GPP.Linear and non-linear regression model was constructed and validated.The results showed that:1) Considering the physiological characteristics of rape,it was necessary to establish a sub-growth model.SR model was the best during the flowering stage,and the model and verification's R2 were 0.80 and 0.82,and RMSE was no more than 2.85 g/(m2·d).During pod phase,CIred edge and MTCI were the preferred model,in the model and verification,R2 were 0.82 and 0.72,and the RMSE was less than 3.91 g/(m2·d).As for the full stage,CIred edge and MTCI were also the preferred model,R2 reached to 0.80 and RMSE was less than 3.67 g/(m2·d).2) In wheat,NDVI model was the best,with R2 of 0.59 and RMSE of 2.80 g/(m2·d).In the prediction set R2 was 0.67 and RMSE was 3.39 g/(m2·d).The results showed that CIred edge and MTCI were not sensitive to the two crops,R2 was ranged from 0.72 to 0.73,indicating that CIred edge and MTCI could be used for the unified GPP inversion in wheat and rape.Keywords：hyper-spectrum;vegetation index;gross primary productivity;rape;wheat;regression model3|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A sugarcane variety ROC22 was studied to build different chlorophyll prediction models based on full-band and dual-band reflectance spectra in the visible-near infrared range,and the accuracies of each model were compared and discussed.Two different ways were considered to explore accurate and applicable models:The first way was to build multiple linear regression (MLR) model (M1) and BP neural network (BPNN) model (M2) with full-band (all of the spectral data) input;For the consideration of engineering applicability,the second way was to build single linear regression (SLR) model (M3),MLR model (M4),BPNN model (M5) with dual-band.M1 and M2 had R2 between the predicted and measured values of 0.792 4 and 0.892 9,respectively.M3,M4 and M5 had R2 of 0.821 2,0.840 1 and 0.848 2,respectively.The results proved that the BPNN model had higher accuracy than the linear regression models although M2 had the highest accuracy.M5 which had the second highest R2 and just needed 2 sensitive bands information was more suitable for engineering application.Keywords：sugarcane;spectral reflectance;chlorophyll content;dual-band;BP neural network1|7|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To realize the effective use of GF-2 remote sensing image in agriculture,Random Forest (RF)、CART decision tree and Support Vector Machine were compared for plastic greenhouse extracted from GF-2 remote sensing images.The method of plastic greenhouses rapid extraction was explored in Wangyefu Town of Neimenggu Province from the GF-2 remote sensing images in this study.Firstly,the optimal segmentation parameter was determined by three indexes:Potential Segmentation Error (PSE),Number of Segments Ratio (NSR) and Euclidean distance (ED).Secondly,various features,including spectrum,texture,shape and neighborhood information were investigated through the popular random forest algorithm prior to classification.Finally,the classification results of RF,CART decision tree and Support Vector Machine were compared.The results show that:1) The method for selecting the optimal combination of parameters values was better applied to the object-oriented plastic greenhouses.2) The trend between the number of features and the classification accuracy was gradually increased and then decreased.RF algorithm can effectively eliminate the redundant and unrelated features while improving the accuracy of the classifier.3) Compared with three classifier based on the optical feature spaces,the Random Forest performed best and the classification accuracy rate was 89.65%,indicating its best applicability in GF-2 image classification.This study would provide references for the application of facility agriculture.Keywords：GF-2 remote-sensing imagery;segmentation parameters;random forest;feature selection;extraction of plastic greenhouses3|8|15<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Winter jujube fruit (WJF) is rich in nutrition,but its harvesting is labor-intensive.Therefore,it is necessary to study the mechanical harvesting of WJF.This study focused on the evaluation of the effect of different vibration frequencies on fruit motion,detaching time and detachment force during mechanical WJF harvesting with a shaker.The shaker was modified from a jigsaw by replacing its saw with a vibrating head.A high-speed camera in 750 fps was used to capture the fruit trajectory on 15 branches excited at the frequencies of 15,20 and 25 Hz.The fruit detaching time,motion patterns,acceleration and inertial force of fruit detaching from limbs were extracted from the high-speed videos.The results showed that the majority of the three identified motion patterns were tilting,column,and beam-column.The tilting motion were accounting for 81%,66% and 78% of all the motion patterns at 15,20 and 25 Hz,respectively.A continuous shaker thus could be used for mechanical harvesting of WJF.Fruit detaching times were significantly affected by the vibration frequency with fruits being fast detached at high frequencies,and their values at the three frequencies were 1.71,0.54 and 0.43 s,respectively.The fruit detaching time at 15 Hz was significantly different from that those at 20 Hz and 25 Hz,whereas there was no significant difference in fruit detaching time between 20 Hz and 25 Hz.The velocity and acceleration of WJF were increased with the increasing of vibration frequency,but the average inertial force of fruit detachment changed less.The detaching force of white ripe WJF was less than that of crisp ripe WJF.In conclusion,higher frequency generates high harvest efficiency,but when the frequency reached a certain value,the increase of frequency had less effect on the detaching time of fruit,and frequency also has little effect on inertia force of fruit detachment.Overall,the results indicate that 20 Hz might be the optimal vibrating frequency and it was possible to selectively harvest the crisp ripe fruit.Keywords：winter jujube fruit;vibration harvesting;high-speed video;motion pattern;fruit detachment1|7|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Real-time and accurate prediction of soil moisture content is of great significance for irrigation management and drought resistance.In order to realize real-time accurate moisture prediction,a comparative study of soil moisture content prediction model was constructed in this study.Taking Yanqing District of Beijing as an example,a comparative study of the soil moisture prediction models were constructed by using the series of soil moisture and meteorological data obtained in this area from 2012 to 2016.Through the correlation analysis,initial moisture content W0,rainfall,humidity,temperature,barometric pressure,ground temperature and evaporation were selected to establish linear regression model,PCA-RBF Neural network model and error backtracking (BP) neural network model,and the prediction results of those three models were compared.The results showed that the accuracy of PCA-RBF neural network model was the highest,with an average precision of 96.8%.The linear regression model and BP neural network model were 94.6% and 95.7%,respectively.The study showed that the PCA-RBF neural network had the characteristics of good stability and high precision,which could well predict the soil moisture content.Keywords：soil moisture content;correlation analysis;linear regression;PCA-RBF neural network;BP neural network2|8|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Aiming at the problem of large power consumption of disc ditcher,an indoor power consumption test system of clockwise and counterclockwise ditching was built.By single factor experiment,the clockwise and counterclockwise ditching power consumptions were analyzed.The result show that:When the ditching depth is 0-368 mm,the power consumption of counterclockwise ditching is greater than the clockwise;When the ditching depth is 368-500 mm,the power consumption of clockwise ditching is greater than the counterclockwise.By orthogonal experiment,do a study about the influence of the ditching depth,cutting wheel rotation speed and forward speed on the power consumption.The test shows that the orders of various factors influencing the power consumption of clockwise ditching is ditching depth > forward speed > cutting wheel rotation speed.The power consumption of clockwise ditching primary and secondary order is ditching depth > cutting wheel rotation speed > forward speed.By adopting the method of multi-factor single objective optimization,a model of power consumption on ditching depth is established,it shows that:When the ditching depth is 185 mm,the rotation speed is 190 r/min,and the forward speed is 0.85 km/h,minimum power consumption of forward furrowing is 29.47 kW.When the ditching depth is 415 mm,the rotation speed is 217 r/min,and the forward speed is 1.03 km/h,minimum power consumption of inversion furrowing is 36.28 kW.Under the condition of two trenching methods,the relative error of theoretical value and experimental value are 7.32% and 2.47%,respectively.It is proved that the power consumption model and the optimization results have higher accuracy.The results provide reference for the product designers to select economic power consumption parameters and working conditions with different working parameters.Keywords：disc type ditcher;clockwise,counterclockwise ditching;power consumption1|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：A total of nine indicators were selected from three aspects:Ecological environment,ground condition and location.The limiting condition method was employed to assess the suitability of reserve cultivated land resources in Shandong Province.The results show that the total area of reserve cultivated land resources in Shandong province is 2 100.09 km2,most of which is other grass.Its spatial distribution displays significant regional differences.The total area of reserve cultivated land resources in Dongying and Dezhou City is relative high,which are 266.59 and 210.91 km2, respectively.While that was relative less in Qingdao,Liaocheng,Zibo and Weihai City,their proportions in Shandong Province are all less than 3%.Different types of reserve cultivated land resources show significant difference in spatial distribution.The difference between the spatial distribution of reclaimable other grass land and inland tidal flats is relatively small.The spatial distribution of reclaimable saline-alkali soil and bare land shows obvious cluster feature.The mining lease has a spatial distribution pattern of "The west higher than the east,while the south higher than the north".The area of centralized contiguous cultivated land resource reservations is 576.67 km2,accounting for 27.46% of total cultivated land resource reservations.Relative scarcity,high fragmentation degree and significant spatial difference are the main characteristics of reserve cultivated land resources in Shandong Province.In cultivated land protection,attentions should not only be paid attention to the balance of quantity and quality,also necessary to improve the utilization efficiency of existing cultivated land and increase the output rate through moderate scale operation.It is necessary to strengthen the rational protection and efficient use of cultivated land resource reservations.Keywords：cultivated land;type of reserve cultivated land resources;suitability assessment;spatial distribution0|8|10<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to promote the financial accumulation and industrial structure optimization and realize the green development of the region,the impact mechanism of financial agglomeration and industrial structure optimization on regional ecological efficiency are analyzed in this study,based on the panel data of 30 provinces and cities in China from 2004 to 2014.A PVAR model is constructed and estimated by using GMM method.Then the impulse response function and variance decomposition method is adopted to analyze the regional differences in the impact of financial agglomeration on ecological efficiency in the eastern,central and western regions.The results show that:Both financial accumulation and industrial structure have steady and positive impact on regional ecological efficiency.The impulse response shows the characteristics of large impact duration,long duration and rapid decline in eastern China while the response of central and western China is not obvious.Variance decomposition shows that the contribution of financial agglomeration has steadily increased,showing the largest contribution from the central region,followed by the eastern and western regions.The industrial structure shows the largest contribution from the west,the second from the middle and the smallest from the east.Based on the results,on the one hand,it will improve the social environment of financial development and strengthen the introduction of financial professionals to guide the development of new industries and ecological industries.On the other hand,the central and western regions should actively undertake the industrial transfer in the east,optimize their own industrial structure and optimize the pattern of industrial division across the country.Keywords：financial agglomeration;industrial structure optimization;regional ecological efficiency;regional differences;panel vector autoregressive model0|10|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to explore the layout optimization of urban emergency material depository,an improved multiple coverage model of emergency supplies repository is proposed in this study.Firstly,considering the road condition has important impact on the effect of emergency rescue,the concept of road damage risk factor and traffic Satisfaction are introduced in this article to build satisfaction attenuation function based on demand satisfaction decreasing within the coverage radius.Secondly,in allusion to the limitation of emergency material depository supplies ability and the dynamic process of emergency rescue work,an urban emergency material depository dynamic multiple coverage model is proposed from the perspective of supply and demand and time dimension.Thirdly,the validity of the model and algorithm is verified by numerical examples.The results shows that the dynamic multiple coverage model can effectively improve the scientific and practical emergency material depository layout.Keywords：emergency material depository;layout optimization;dynamic;multiple coverage;immune optimization algorithm0|7|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to understand the differences in the supply reaction of mutton sheep and the reasons behind and ensure the long-term stable supply of farmers and herdsmen and the mutton in our country,using the dynamic panel data from January 2012 to December 2016,based on the Nerlove model,the causes of the differences in the supply response of mutton under different breeding modes is analyzed in this study.The results show that:The elasticity of supply responses of professional fattening is higher than that of numerous bred households;The influence of livestock forage price,discount and policy of environmental factors on professional fattening households were also significant than numerous bred households.Based on analyzing the reasons for differences,proposes are put forwarded to improve the professional quality,the key support threshold of fattening breeding ewes,strengthening grass supporting capacity,the establishment of major animal disease monitoring and early warning system,improve sheep production and price monitoring and early warning system so as to ensure the healthy development of China's sheep industry.Keywords：sheep;self-breeding and self-feeding;professional fattening;breeding mode;supply response0|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on a survey of five provinces in China on 2014,the situation of rural household waste funding and residents' willingness to pay for waste collection are studied and whether the money collected from the residents can become a way to cover the cost of rural household waste collection is explored.The result shows that the current cost of rural household waste collection is about 23.21 yuan/(month·person) and the willingness of rural residents to pay for the waste collection fee is about 6.50 yuan/(month·family).The gap between the two shows that:With the reference to the willingness to pay for rural household waste,waste charges itself is difficult to solve the problem of shortage of waste collection funding.However,the willingness of rural residents to pay for waste collection services does exist.The age,educational level,cadre status and assessment of the health of rural residents are significant factors influencing their willingness to pay.At present,more and more rural areas have already begun to levy household waste charges,which may fill some of the gaps of the rural household waste collection funds.However,household waste collection still needs investment from government and the introduction of social captial at the current level.Keywords：rural household waste;disposal cost;willingness to pay;waste fee0|7|7<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study is to explore the development and policy formulation of China's pelagic fisheries by using Japanese experiences based on its historical data.The development of Japan's pelagic fisheries and quantitative analysis and its structural changes is quantitatively analyzed.The study summarized:1) There are two successful experiences of the transformation and upgrading policies in Japanese history;2) The lessons is the stage of decline since 1970s to present.This study demonstrates that the recession of Japan's pelagic fisheries is not only affected by the external factors of international environmental change,but also by the internal factors.The government's ocean-going incentive policy is out of date,and the solution has not been found so far.This study clarifies the path of transformation and upgrading of Japan's pelagic fisheries.By learning from experiences and lessons of Japan,it is necessary to perfect the subsidy policy,provide financing facilitations,promote fish culture reform and reinforce the construction of enterprises to build their own capacity for the development and policy formulation in China's pelagic fisheries.Keywords：pelagic fishing vessel industry;fishing vessel;transformation and upgrading;policies;Japan0|8|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aims of this study were to comprehensively and objectively present the research status and development trend of the risk assessment of invasive pest over last decade and provide references for establishing effective prevention and control strategies against invasive pests.The risk assessment of invasive insects was bibliometricly analyzed based on literatures indexed by the Chinese and English document databases during 2007-2017,and total 885 literature associated with this field were obtained.The results showed that the number of published papers related to risk assessment of invasive insects is the most in 2014.The journal of Biological Invasions,published most papers related to risk assessment of invasive insects among the international journals,while the Plant Quarantine journal published most articles among the domestic journals.The number of scientific papers associated with Hymenoptera insects was the most among the international journals;meanwhile the number of scientific papers associated with Coleoptera insects was in majority among the Chinese journals.Additionally,the numbers of paper related to risk assessment of three invasive insects,such as Linepithema humile, Solenopsis invicta and Bactrocera dorsalis were the most among the international journals.The basic principles,advantages and disadvantages and application of four commonly used ecological niche models for suitability assessment of invasive pests were briefly introduced to provide reliable guidance for researchers who engaged in invasive biology.Keywords：alien invasive insects;risk assessment;ecological niche models3|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
