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- Abstract：To determine suitable soaking and illumination time for the production of fava bean sprouts,the influence of different soaking time (12,16,20,24,28 h) and illumination time (8,9,10,11,12 h/d) on the growth and quality of fava bean sprouts were analyzed in this study.The results showed that the seedling length,stem fresh weight and edible rate of fava bean sprouts increased with the soaking time.After 16 h of seed soaking,the growth indexes and soluble protein content of fava bean sprouts were significantly higher than those of 12 h.Except for 16 h,L-DOPA content was significantly less than 12 h in all the other soaking time.With the extension of illumination time,the growth of fava bean sprouts slowed down significantly.When the illumination time was 9 h/d,the L-DOPA content was significantly higher than that of 8 h/d,and there was no significant difference with other treatments.Soluble protein and sugar reached the optimal content at 9 h/d illumination time.The L-DOPA content was taken as the main index,and both nutrition and growth indexes were taken into account.The optimum soaking time and illumination time for fava bean sprouts production were 16 h and 9 h/d,respectively.Keywords：fava bean sprout;soaking time;illumination time;L-dopa;growth;quality4|14|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to analyze the environmental factors affecting the main agronomic and quality traits of sweet sorghum,experiments were conducted in four regions of Tianjin,Xinjiang Uygur Autonomous Region,Inner Mongolia Autonomous Region and Liaoning Province with different genotypes of sweet sorghum as study materials.The relationship between the target traits and environmental factors were analyzed and a prediction model for target traits was established.The results showed that:The plant height,stem diameter and the number of stem nodes of sweet sorghum were dominated by genotype effect;Its panicle length was dominated by genotype×environment interaction and genotype effect and panicle weight was dominated by environment effect;Brix and crude protein content were the result of the average interaction of genotype,environment and genotype with environment.The brix was positively correlated with soil pH value,organic matter content and available phosphorus content,while the crude protein content had no significant correlation with diurnal temperature difference and organic matter content,but it was positively correlated with eight other factors such as precipitation;Path analysis and stepwise regression analysis showed that daily average temperature,diurnal temperature difference,soil pH value and available phosphorus content were the main factors affecting panicle weight,among which soil pH value had the greatest and negative effect; ≥ 10℃ effective accumulated temperature,soil pH value and organic matter content were the important factors affecting the brix,and the contribution rate of organic matter content was the highest,which had a positive effect on crude protein content.The key factor affecting the crude protein content was precipitation.Keywords：sweet sorghum;traits;environmental factors;genotype;environment;interaction effect0|8|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To study the relationship between the physical characteristics and seed vigor of barley germplasm,a total of 44 colored barley germplasms were taken as study object.Combination of germination test and computer image recognition was used to determine the relationship between seed physical characteristics and seed vigor of colored barley by measuring the germination characteristics and seed physiological characteristics of barley seeds.Correlation analysis,principal component analysis and stepwise regression analysis were conducted.The results showed that:The germplasm vigor of colored barley was positively correlated with the Y (Yellow) value of seed coat color,and the other color characteristics were negatively correlated with the germplasm of colored barley.Stepwise regression analysis showed that the effect of seed coat color on the vigor of colored barley germplasm was greater than that of seed physical characteristics,grain length and grain thickness.The seed physical characteristics showed that the grain length,grain width,grain thickness and 1 000-grain weight were not significantly related to the seed vigor of colored barley,and the main color characteristics affecting the vigor of colored barley germplasm are H (hues) value and a (range from magenta to green),and are negatively correlated;In addition,the Integrated optical density (IOD) value is extremely positively correlated with the grain length and the grain width.Keywords：colored barley;seed morphology;seed color;vigor;image identification2|8|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to clarify the effect of pre-winter compaction and irrigation on the growth of winter wheat,a field experiment was carried out during 2016-2017 winter wheat growing season.Pre-winter compaction + irrigation (C+I),irrigation (I) and compaction (C) were applied to the winter wheat variety ‘Jimai 22’,the normal growing plant was used as a control (CK),and the plant morphology and yield were analyzed in this experiment.The results showed that the tiller number and effective spike rate of tiller were increased and the final height of the wheat was highest in C+I,followed by I,C,and CK treatments.The length of the basal first and second internodes of wheat was reduced,and the unit length dry weight,stem thick and wall thickness were all increased significantly in C+I,followed by C and I treatments compared with control.The transferred amount,transfer rate of the pre-anthesis stored dry matter and its contribution rate to grain yield were reduced by C+I,C and I,with the maximum reduction found in C+I,followed by C and I.However,the amount of dry mater accumulated during post-anthsis and its contribution rate to grain yield were the highest in C+I.The spike number per unit area,final yield and harvest index of C+I treatment were all maximum and higher than C,I and CK successively.In conclusion,these result showed that pre-winter compaction+irrigation or individual irrigation or compaction could promote wheat growth and increase the lodging resistance and final yield of wheat.The combination of compaction and irrigation is greater than individual measures.Therefore,the pre-winter compaction + irrigation measures in production is optimal for the growth of winter wheat in Shandong Province.However,even under the situation of no irrigation conditions,pre-winter compaction is also beneficial to wheat production.Keywords：wheat;compaction;irrigation;plant morphology;yield2|10|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To explore the effect of 60Co-γ irradiation mutagenesis on bud breaking of fig one-year-old canes and young shoots of different maturation level,the one-year-old hardwood of three fig cultivars ‘117D’,‘Green Peel’ and ‘110C’,and the young shoots of two fig cultivars ‘108B’ and ‘110C’ were used as the materials.The highest dose of 60Co-γ irradiation were set at 160 J/kg for hardwood cuttings and 200 J/kg for young shoots,bisection decrease was used to make a ladder of irradiation doses.After the treatment the hard wood cuttings were soil rooted and the young shoot cuttings were put in a hydroponic container.The bud breaking rate of the cuttings was observed and calculated.The result showed:Under the dose of 160 J/kg irradiation,all the hardwood cuttings of the three cultivars were died;while very significant difference on cutting bud breaking rates were found between 40 and 80 treatment and among different cultivars.Among the three cultivars,‘117D’ demonstrated the highest tolerance to the irradiation,while ‘Green Peel’ showed the lowest tolerance;For the young shoot cuttings,‘108B’ and ‘110C’ cultivar were all died under 200 J/kg irradiation in regardless their maturation level.Very significant difference on bud breaking rate was revealed with irradiation doses of 50 and 100 J/kg and among three levels of shoot maturation levels revealing that the maturation level of young shoot cuttings was negatively correlated with the irradiation dose tolerance.The tolerance of ‘108B’ young shoot cuttings was higher than that of ‘110C’ cultivar.Further observations demonstrated that irradiation treatments led to delayed bud breaking and repressed root formation of cuttings.In conclusion,for bud mutagenesis irradiation treatment,the suitable 60Co-γ irradiation dose to fig hardwood cuttings was between 40-80 J/kg; for the young shoots,the suitable dose was between 50-100 J/kg;and different fig cultivars display different sensitivity to 60Co-γ irradiation.0|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study was to investigate the effects of chronic cold stress on serum enzyme activity,serum protein and hormone secretion of HPA and HPT axis in Mongolian cattle.Eight Mongolian cows with similar body condition and healthy constitution were randomly selected from Xilingol grassland of Inner Mongolia.The jugular vein blood was collected and serum was prepared on the morning of the last day of the experiment.The serum enzymes such as alkaline phosphatase (AKP),creatine kinase (CK) and lactate dehydrogenase (LDH) were detected by ELISA.The contents of HPA,HPT axis hormone,total protein (TP),albumin (ALB),urea nitrogen (BUN) and other serum proteins such as triiodothyronine (T3),thyroxine (T4),adrenocorticotropic hormone (ACTH),growth hormone (GH) and so on.The results showed that cold stress produced certain stress on Mongolian cattle.Compared with non-stress period,the secretion of serum hormones such as T3,T4,ACTH and GH in Mongolian cattle blood increased significantly under cold stress (P<0.05).The content of AKP in Mongolian cattle blood decreased significantly under cold stress (P<0.05),while the content of other enzymes did not change significantly (P>0.05).The content of BUN in Mongolian cattle serum increased significantly under cold stress (P<0.05),but there was no significant difference in the content of TP and ALB.Written influence (P>0.05).In conclusion,cold stress caused stress to Mongolian cattle.The HPA and HPT axes were activated to increase heat production in order to adapt low temperature environment.Compared with non-stress state,the blood biochemical indexes of Mongolian cattle,such as TP,ALB,CK and LDH,had no significant changes,indicating that Mongolian cattle were better adapted to the alpine environment of Mongolian plateau after many years of natural selection and artificial breeding.Keywords：Mongolian cattle;cold stress;serum;enzyme activity;protein;hormones0|9|11<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to analysis the effects of different feeding methods on the nutritional composition of Tibetan pork,18 300-day-old Tibetan pigs were selected for feeding and grazing.The longissimus dorsi muscle of pig was sampled for amino acid,fatty acid and trace mineral elements analysis.The results showed that the glutamate content of the pigs in the house feeding group was significantly lower than that in the grazing group (P<0.05) and its total amount of umami amino acids,glycine and alanine were significantly lower in the grazing group (P<0.01).In addition,the MEAA/MTAA ratio of both groups were around 40% and MEAA/MNEAA was higher than 60%,which met the ideal protein requirements.The total amount of polyunsaturated fatty acids and essential fatty acids in the feeding group were significantly lower than those in the grazing group (P<0.01).The dietary recommendation MPUFA/MSFA was preferably higher than 0.4,and the grazing group was higher than 0.45,which was the ideal ratio.The results of trace mineral elements analysis showed that the content of zinc and chromium in the feeding group was significantly lower than that in the grazing group (P<0.01),and the selenium content was significantly higher than that in the grazing group (P<0.05).In summary,the grazing feeding Tibetan pork had a better fatty acid composition and flesh flavor than those of the house feeding pigs.2|7|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to study the effects of different doses of chicken spleen transfer factor (TF) on the development of intestinal mucosal barrier in layer chickens,200 5-day-old SPF egg chicks with the same body weight and growth were selected and randomly divided into low-dose group,medium-dose group,high-dose group and control group with 50 chicks in each group.Chicks were treated with different doses of oral TF (0.10, 0.25 and 1.00 mL each) from 5 days old,in an intermittent administration way with one week of drug administration and one week of drug withdrawal.Intestinal tissues were collected at 12, 26 and 40 days old.Paraffin section and HE staining was performed.Histological changes were compared in different TF dose groups.Compared to that of control group,the results showed that at 12 days of age,the height of intestinal villi increased and the depth of crypt decreased,especially the ratio of the two changed significantly:ratios of duodenum with the middle and high dose groups were significantly increased 26.00% and 26.96% compared with the control group;In jejunum,the ratio was obviously increased 29.45% in high dose group;it increased significantly (19.74%-29.32%) in ileum each group.At 26 days of age,the changes of intestinal mucosal structure were similar to those of 12 days old,especially,the ratio of villus height and crypt depth of duodenums was increased significantly in middle (9.46%) and high (9.90%) doses groups;there was a significant increase by 12.99% in jejunum in the high dose group;it increased significantly (17.07%-25.60%) in ileum each dose group.At 40 days of age,the ratio of duodenum increased significantly by 17.97% (middle doses) and 22.19% (high doses),respectively.The ratio of jejunum increased significantly by 28.68% in the high dose,and it increased significantly (17.04%-25.56%) in ileum each group.Therefore,the ratio of villus height and crypt depth of the small intestine was increased in the high dose TF feeding groups,and it was positively correlated with the applied dose.Therefore,TF can effectively improve the digestion and absorption function of the small intestine.Keywords：layer chickens;chicken spleen transfer factor;intestinal mucosal barrier;intestinal villus height;crypt depth0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate genomic organization,expression and phylogeny of the TCRδ,which including VHδ gene in Peking duck,a Peking duck BAC genomic library was screened and a BAC clone containing the second TCR δ locus was sequenced in this study.The total length of the BAC insert is about 136 Kb.A detailed analysis of the BAC sequence showed there were no introns among VHδ, Dδ and Jδ genes,which suggested that they have recombined on the genomic level.Then a complete genomic structure of the second TCR δ locus in the Peking duck was identified,which is organized in an unusual pattern,SPPL2A-VHδ-Dδ-Jδ-Cδ-OR-OR.Syntenic analysis suggested the second TCR δ locus of Peking duck syntenic with chicken's second TCR δ locus.And the mRNA levels in different tissues are measured by Q-PCR.Phylogenetic analysis shows that all Cδ and VHδ genes from birds are clustered together,indicating that all Cδ genes of birds are derived from a common ancestral gene.The gene is either duplicated or lost in different birds during evolution.In summary,this study would provide insight into the evolution of the second TCR δ in birds and improve our understanding of the duck immune system and the evolution of TCRδ genes in birds.Keywords：Peking duck;VHδ;gene;TCR;δ;locus;evolution0|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In view of the problem of grassland degrading in natural Leymus chinensis,single factor randomized block design was adopted in this study.A total of 7 treatments with three replicates were as follows:No fertilization treatment was taken as the control group (CK);Three sputum treatments were respectively 45 t/hm2 (QYh),30 t/hm2 (QYm) and 15 t/hm2 (QYl);Three slag treatments were respectively 45 t/hm2 (JZh),30 t/hm2 (JZm) and 15 t/hm2 (JZl).The results showed that:1) pH and available P of QYh treatment increased significantly in 0-10 cm soil layer,and the available K of JZh treatment increased significantly compared to the control.The available N,available K and total K increased significantly under QYh treatment in 10-20 cm soil layer,while no significant soil nutrients differences were found in the remaining treatments.2) No significant changes were discovered in the urease activity between treatments.The sucrose activity was significantly decreased by 24.35% under QYm treatment compared to the control.The alkaline phosphatase activity increased under QYh and JZh treatment compared to control,there was no significant difference in the catalase activity.3) The alkaline phosphatase activity was significantly positively correlated with organic matter in surface soil.The catalase activity was significantly positively correlated with soil pH,positively correlated with available K,and significantly negatively correlated with total K in 10-20 cm soil layer.The urease activity and available K were significantly negative correlated,sucrose activity and available N were significantly positive correlated,alkaline phosphatase activity was significantly positively correlated with available K,and positively correlated with pH,catalase activity was significantly positively correlated with available K in 20-30 cm soil layer.4) Soil enzyme activity decreased with increasing depth of soil profile.In conclusion,the application of slag and sputum manure displayed positive effect on the soil nutrient and enzyme activities in the Leymus chinensis steppe,and the impact of 45 t/hm2 sputum manure or 45 t/hm2 slag was the greatest.Keywords：Leymus chinensis;organic fertilizers;sputum;slag;soil nutrient;soil enzyme activity4|10|7<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to realize the real-time remote monitoring of multi-machine cooperative navigation operation,a remote management platform is designed and developed for multi-machine cooperative navigation operation.The platform mainly includes job management and dispatching management module.The job management module uses electronic map to realize remote monitoring of multi-machine cooperative navigation operation information,real-time analysis of job progress and online evaluation of job quality.The dispatching management module mainly includes multi-information acquisition and processing,as well as precise positioning through electronic maps to achieve multi-machine cooperative navigation operation task planning and path planning.The results show that the platform can monitor the track and operation information of multi-machine cooperative navigation in real time,and can realize the remote dispatching management.The packet loss rate of remote communication is less than 0.3% and the delay is less than 2 seconds,which can initially meet the needs for multi-machine cooperative navigation.Keywords：multi-machine cooperation;electronic map;job management;dispatching management2|7|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to solve the low level of mechanization in the process of apple picking,a bionic-nondestructive apple picker was developed based on the mechanism of apple picking by hand and the way of catching prey by using octopus suckers.The apple picker was mainly composed of air suction end-effector,positioning support mechanism,real-time on-line picking monitoring system and quality monitoring system.Finite element static strength analysis and dynamic modal analysis were carried out on the key parts of the picking device to ensure the rationality of the design scheme.The results showed that:1) The prototype could pick apples with 3 m apple tree height,60-90 mm of tree diameter,and 3.3-4.8 mm of apple stem diameter.2) The prototype used an air-suction end-effector with 3-joint universal joint can adjust the position and posture of the end-effector to keep the same as the fruit growth posture,and avoid the obstacles caused by leaves and branches to achieve the best position.3) After stretching the same batch of 30 apples of similar size,quality and intact surface,it was found that the suction force of the prototype didn't cause damage to the apple epidermis,and no damage was found in the internal pulp tissue of the apple after being pared for 7 days.Keywords：apple picker;bionic design;nondestructive picking;suction type1|11|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Aiming at problems of the changes the surface wetting radius (r) and the vertical infiltration depth (h) with time under single dripper in surface drip irrigation,a indoor soil column method and rational design method were conducted.The parameters in the power function equation of r,h and infiltration time (T) were estimated based on experimental data,and the mutual constraints among these parameters were tested.In the study,a series of infiltration experiments were conducted with silt loam,including three soil bulk densities (1.3,1.4 and 1.5 g/cm3),and four dripper discharge (1,2,4 and 8 L/h).The changing processes with time of wetting radius (r) and the vertical infiltration depth (h) under single dripper irrigation were recorded.The results showed that:1) The saturated soil water content and h decreased with the increasing of the soil bulk density,while the soil bulk density showed little effect on r.2) The infiltration parameters (A,B) and power exponent (C,D) were estimated and tested by the rational design method,the mutual constraint conditions were satisfied among the parameters,and the error was small.It indicated that the changing process of r and h could be calculated based on the power function and the parameters (A, B,C,D).3) For a given irrigation amount of 2 L,the vertical infiltration depth was relatively deeper when the dripper discharge was 1 L/h,which could easily resulted in deep percolation.Meanwhile,the duration of one irrigation calculated by rational design method was relatively longer,and it met the requirements of field rotation irrigation;The surface wetting radius was relatively larger when the dripper discharge was 8 L/h,resulting in surface water accumulation near the dripper.In conclusion,the flow rates of 2 and 4 L/h were more suitable for the drip irrigation under silt loam soil condition.This study indicated that the rational design method could be used as a tool for optimal design of drip irrigation system.Keywords：surface drip irrigation;drip discharge;rational design method;wetting front0|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In view of the lack of theoretical support for environmental regulation and control of solar greenhouse,the difficulty of monitoring and utilizing environmental information and quantifying crop growth,tomatoes planted in solar greenhouse in spring and summer of Beijing were used as experimental materials to study the effects of greenhouse environmental parameters on the growth of tomatoes.Devices of IOT in agricultural were used to monitor main environmental parameters (greenhouse air temperature,relative humidity of air,CO2 concentration,intensity of illumination,soil temperature and soil moisture) and tomato growth indexes (stem diameter micro-variation,fruit diameter micro-variation and leaf surface temperature) in solar greenhouse.The models were built on the platform of Matlab 2014a.The results showed that:1) A regression model of the effects of environmental parameters on stem diameter micro-variation,fruit diameter micro-variation and leaf surface temperature in fruit stage and a regression model of the effects of environmental parameters on stem diameter in seeding stage were established.The influence of different environmental parameters on the slight change of stem diameter,fruit diameter and leaf temperature of tomato were reflected through the model;2) A prediction model of tomato fruit diameter was established.The correlation coefficients of training set and testing set were respectively 0.92 and 0.88,which met the prediction requirements;3) The reasonable control range suitable for growth of tomatoes of the main environmental parameters in the seedling and fruit stages obtained from the experiment analysis were proposed.A reference was provided for the environmental regulation of tomato production in solar greenhouse in spring and summer.Solutions were also provided for the intelligent association between environmental data monitoring and environmental regulatory agencies though the study.Keywords：solar greenhouse;tomato;stem diameter micro-variation;fruit diameter micro-variation;environmental factors5|8|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the heat preservation and lighting performance of plastic greenhouse and select suitable greenhouse type for annual production of greenhouse crops,this study designed and selected five large span asymmetric plastic greenhouses,namely 17 m span single-layer (FG-17-1) and double-layer plastic greenhouse (FG-17-2),18 m span single (FG-18-1) and double-layer plastic greenhouse (FG-18-2) and 20 m span single-layer plastic greenhouse (FG-20-1),to measure and analyze the temperature and light environment of typical weather and be compared with traditional arch plastic greenhouse (G-8-1) and Chinese solar greenhouse (CSG) as the control.The results showed that:The minimum temperature of FG-18-2 was higher throughout the year,and the spring and autumn season were above 13.0℃,which were only about 0.5℃ lower than CSG and about 4.0℃ higher than G-8-1;Its minimum temperature in winter was 4.2℃,2.1℃ lower than CSG,16.3℃ higher than G-8-1.With no extreme low temperature,high thermal insulation performance,FG-18-2 could ensure the normal growth of crops temperature and soil temperature,free from low temperature damage.The light intensity in FG-18-2 greenhouse was 47.86%-64.62% higher than G-8-1 in winter.The north-south direction of light was relatively uniform,and the lighting performance was better,which could meet the lighting requirements for the growth of crops.In conclusion,there is no extreme low temperature or high temperature in the FG-18-2,small difference between the north-south span direction of light,best thermal insulation performance and better lighting performance,which is more suitable for promotion and application in the annual production of facility crops.Keywords：plastic greenhouse;large-span;asymmetric;temperature;light intensity2|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to quantitatively evaluate the environmental impact of straw pyrolytic poly-generation project,life cycle assessment (LCA) is referenced to build an integrated LCA framework.The material and energy inputs of construction unit and their environmental emissions are included in the system boundary.The environment performance of straw pyrolytic poly-generation system with annual straw processing capacity of 1.0×104 tons is calculated in this study.The results show that the total global environmental impact load of processing 1.0×104 tons of crop straw by straw pyrolytic poly-generation system is 175.53 PE (person equivalent).The environmental impacts of construction unit,operation unit and product utilization unit account for 18.10%,78.75% and 3.15%,respectively.The environmental impact of steel and PVC pipe accounts for 93.49% of the construction unit.The environmental impact of electricity consumption accounts for 93.86% of the operation unit.From the perspective of resource substitution for coal,pesticide and fertilizer,the system environmental impact load is -496.86 PE.The straw pyrolytic poly-generation project decreases the environment emission and shows good environment impact.It is necessary to reduce electricity consumption and use low-carbon and environmentally-friendly building materials in straw pyrolytic poly-generation system in the future.Keywords：straw;pyrolytic poly-generation;life cycle;environment impact;emission reduction caused by resource substitution0|7|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to evaluate the coordinated development degree of different counties in Hebei Province and clarify the key points of land consolidation,entropy method and coordinated development degree model are adopted in this study to evaluate the degree of artificial-ecological spatial coordinated development and classify land consolidation types.The results indicate that:1) The four sets of indicators are living space,livelihood space,production space and natural space,which are constructed by two subsystems of artificial space and ecological space,comprehensively evaluate the spatial coordinated development level of each county.It provides new ideas for spatial use control.2) In Hebei Province,20 counties are ecological lagging of transitional development type.Two counties belong to the eco-ecological synchronization of transitional development type,and 15 counties are the economic lagging of transitional development type.For the disordered decline type,87 counties belong to ecologically lagging type,while 3 counties are economic and ecological synchronizing type and 41 counties are economically lagging type.3) The types of land consolidation in Hebei Province are divided into four spaces including priority consolidation of ecological space,priority consolidation of artificial space,focal consolidation of ecological space as well as focal consolidation of artificial space.Keywords：spatial classification;the coordinated development degree;land consolidation;Hebei Province0|11|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To explore the characteristics and driving forces of the ratio of land use and cover change in Jinghe oasis in recent 20 years,Jinghe oasis was chosen as the main data source of Landsat remote sensing image data,meteorological data,hydrological data,social economic data,dynamic attitude and time series tracking.The results showed that:1)The changes mainly reflected in a transformation of cultivated land to high-coverage vegetation,a serious degradation of medium-cover vegetation,and a decreasing trend of wetland area from 1997 to 2016.2)The coverage and area of other land cover types,cultivated land and proportion of water continued to increase in 1997,2007 and 2016,the amplification were 12.17%,5.30% and 2.49%,respectively.The vegetation of high/middle/low coverage and wetland displayed a decreasing trend,among them,the vegetation of low-coverage was the fastest which decreased by 13.23%.Meanwhile,the vegetation of middle-coverage showed an increasing trend in the first 10 years,then decreased in the second 10 years.3)The land cover change of Jinghe Oasis was affected by both natural and human factors.Natural factors limit the survival of low-coverage vegetation between mountainous areas and plain areas.Human factors are the direct driving force for land cover change in oasis.Keywords：LUCC;spatial-temporal changes;driving analysis;Jinghe oasis;arid area1|8|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：According to the Landsat satellite imagery and other ancillary data in 1990,2005 and 2015,the remote sensing (RS) human-computer interaction visual interpretation method was used for supervised classification,and the spatial analysis and statistical functions of geographic information system (GIS) were applied.The three-stage land use transfer matrix and the dynamic change map of land use types from 1990 to 2015 were produced,the dynamic characteristics of land use in the Linzhi region of Tibet and the transformation between various types were analyzed.The results showed that:The land use types in the study area were mainly forest land,unused land,grassland and water area.Among which the forest land area was the largest,accounting for 52.5% of the total area of Linzhi area and followed by unused land,accounting for 25.9%.From 1990 to 2015,the forest area of Linzhi area decreased by 118.4 km2,and the area of change was the largest,which was mainly converted into grassland and unused land;The water area and unused land were second,and the area increased by 32.65 and 32.06 km2,respectively.The water area was mainly composed of unused land and the conversion of grassland was mainly caused by the conversion of grassland and forest land;The area of cultivated land increased by 26.89 km2,which was mainly converted from forest land.The urban and rural areas,industrial and mining,residential land and grassland area increased by 16.96 and 9.84 km2.The magnitude of the change was relatively minimal.In conclusion,there are obvious regional differences in land use change,and the change in the northern part of the Linzhi region is significantly stronger than that in the south.Keywords：GIS;RS;land use;dynamic changes;spatial analysis0|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to promote the innovation of China's land management system,this paper uses the method of literature analysis to clarify the core of Chongqing and Chengdu's land management system,and provides corresponding suggestions based on the characteristics of China's first and second-tier cities.The results show that:the prominent feature of Chongqing and Chengdu land ticket systems is to convert the inefficient rural land into the development space available for urban construction,and to free up the construction land index to meet the rural development by renovating the inefficient rural construction land.Moreover,the public transaction of land use indicators in a market-oriented way can not only introduce social capital to participate in the remediation of inefficient construction land in rural areas,but also optimize the spatial distribution of urban and rural land through market allocation of construction land indicators.And for first-tier cities,they can combine the land ticket system with the urban renewal policy to realize the redevelopment of the existing land.As for the second tier cities,they can issue the number of land ticket replacements for different plots of land on the basis of the land ticket system to ease the shortage of land resources.Keywords：land ticket system;land innovation management system;Chongqing;Chengdu1|7|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to investigate the development potential of conservation tillage,under the context of climate warming and extreme weather events,this study assesses the determinants of farmers' willingness to adopt conservation tillage,especially focus on the farmers' perception of extreme weather events and their income level by using the Logit model and complementary log-log model based on 897 household survey data from different provinces such as Henan and Hebei.The results showed that:Farmers' willingness to conservation tillage is affected by the frequency of extreme weather events.Among the survey farmers who perceive extreme weather events occurs once in a year,the middle-income farmers are less willing to adopt conservation tillage than the higher-income farmers.In addition,farmers who receive more education,participate in agricultural cooperatives and have a larger area are more likely to adopt conservation tillage.In conclusion,the agricultural department can promote conservation tillage in areas with more extreme weather events,and among farmers with larger planting area and higher income level.Keywords：conservation tillage;willingness;extreme weather events;perception;income0|8|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the survey data of three pig farm households in Beijing,Liaoning and Hebei provinces,this study empirically analyses the influence of transaction mode on the quality and safety control behavior of farm households.The study found that,because of the different economic connotation of the quality attribute and the safety attribute of the pig,the influence of the transaction mode on the quality and safety control behavior of the farm households is different:Compared with the market transaction,the contract with the slaughterhouse has significantly improved in the quality control and safety control of the farm households.The contract with pig buyers helps improve the quality control of farms,but is not conducive to their safety control.In addition,the individual characteristics,the production characteristics,the external environment,the expected return and the cognitive level of the farm households have affected the quality and safety control behavior of the farm households.Suggestions are put forwarded accordingly as following:Pay attention to the coordination of government regulation and market management,strengthen the supervision with management of pig buyers and sellers and raise the organization level of farmers.Keywords：transaction mode;farm household;quality and safety of pig;control behavior;industrial organization0|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Meta-frontier method was adopted to measure and compare the egg farmers' technical efficiency of different scales under the common production frontier in the last ten years.The results showed that:In the past ten years,the technical efficiency of the small-scale farmers was in basic level;The medium-scale farmers increased investment in fixed assets,improved the technology level but decreased the technical exertion degree.It caused short-term fluctuations in technical efficiency and the farmers obtained higher level technical efficiency finally;the large-scale farmers improved the level of management and higher level of management influenced technical efficiency from the two aspects of technical efficiency.However,but the large-scale farmers technical efficiency was relatively low.In conclusion,the development of the middle-scale egg farmers is still in the initial stage and needs further improvement.Keywords：meta-frontier;scale evolution;technical efficiency;layer culture0|7|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In view of the problem of large fluctuations in the profit of laying hens breeding company,this study uses egg,corn and soybean meal futures to design industry chain hedging plan,estimates the hedging ratio through OLS,B-VAR and ECM models,and finally compares and analyzes the effect of hedging.The results show that:1) The futures prices of eggs,corn and soybean meal are highly correlated with spot price,so that the feasibility of hedging is provided;2) When the egg price is expected to fall in the future period,the egg chicken breeding company can sell egg futures in advance for hedging,while buying corn and soybean meal futures to reduce the risk of spot profit fluctuations;3) The effect of hedging with the hedging ratio estimated by the OLS model is better than those estimated by the ECM model and the B-VAR model over the selected time period,that is,the hedging value is higher and the standard deviation is lower.Therefore,the egg producers can use the futures market for industry chain hedging to reduce the market risk.Keywords：egg futures;hedging ratio;hedging plan;hedging performance;industry chain1|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To clarify the development status of rural financial market in China and explore the influence mechanism of rural credit market and agricultural insurance market on the formation of large grain farmers,this study adopts the research method of literature review to systematically review and theoretically sort out relevant researches.The results show that:First,it is of great practical significance to moderately expand the scale of food and agriculture operations for the development of agriculture in China.Second,whether the development of rural financial markets is perfect or not,it is the key to expanding the scale of food and agriculture operations.Thirdly,at this stage,China inadequate development of rural financial markets in China is not conducive to farmers to obtain credit and insurance.In conclusion,the imperfect credit market is obstacle for the grain and agricultural farmers to get access capital and not conducive to factor substitution and expand the scale of production.The imperfect insurance market is obstacle for the grain and agricultural farmers to get access insurance and not conducive to production stability after the expansion of scale.Keywords：credit;insurance;large grain farmer;literature review1|7|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the field research data of peasant household in Anding District of Dingxi City,Gansu Province,an empirical study on the technical efficiency and influence factors of potato production in the mountainous areas in Northwest China was conducted by using the translog stochastic frontier model.The results indicated that the overall level of technical efficiency of potato production in mountainous regions was lower,which implied a large space for improvement.Specifically,the average value of technical efficiency in medium-scale peasant household was higher than that in small-scale or large-scale farmers household.For the influence factors on potato production,it was revealed that in the characteristics of peasant household including the degree of specialization,cognitive level and labor forces had positive impacts on the technical efficiency of potato production.In the variables of producer services,only the fertilization positively affected the technical efficiency of potato production.In the variables of land features,a negative influence of the lands' scale on the technical efficiency of potato production was also found.Therefore,potato production transformation that improves the quality and efficiency in peasant household should be encouraged by the government.It is necessary to explore the moderate scale management of potato production to achieve the regular integration between peasant household and the modern agriculture development.Keywords：mountainous area;scale difference;technical efficiency;influence factor;potato0|8|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
