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- Abstract：In order to solve the developmental problem caused by the unreasonable structure and achieve the efficiency from land use structure, a multi-objective programming model is constructed in this study. The targets of the objective function and the constraint conditions of regional land use are quantified by ISM and fuzzy two stage algorithm is used to optimize the land use structure. Taking Quzhou County as an example, the current plan (2012) is compared with the optimization scheme and the natural evolution of land use structure (2035), which is operated by the Markov algorithm. The results show that:1) The satisfaction of optimized utilization structure (2.87) is significantly higher than the current plan (2.80), natural evolution scheme (2.23). And the rationality also is the highest one. The optimization scheme has a certain validity. 2) Taking an analysis on the natural evolution scheme, it is found that the current economic driving mode in Quzhou County causes damage to its water resources and regional ecological benefit. And it is also not conducive to the improvement of the ecological environment. The main concluions are:1) Based on the multi-objective optimization model, the optimization method of land use structure embedded in ISM and fuzzy analysis has implications for the optimization of regional land use structure. 2) Combining regional land-use optimization objectives, maintaining the relative stability of the rest of the land structure, and coordinating the balance between cultivated land, residential quarters and industrial land, forest land and unused land are the basic approaches for optimization of regional land use structure.Keywords：optimization of land use structure;multi-objective programming;interpretative structure model;fuzzy two stage algorithm2|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Of the E-series gene, E1-E4 genes affect on soybean growth periods greatly and are closely related to the ecological type of soybean variety. In order to summarize the research progress and application status of the main growth stage gene E1-E4 of soybean and promote the formation of soybean breeding pattern in China, this study overviews different genotypes and genotyping methods and of E1-E4 genes. The applications of E1-E4 genotype information of soybean population on growth adaptation analysis are also summarized. This review can provide guidance on the research of genetic regulation mechanism of soybean growth period, and theoretical basis on genetic breeding of soybeans cultivars adapting to different ecological areas.Keywords：soybean;growth period;ecological suitability;1-;E;4;variation type;application1|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To explore the salt-tolerant physiological mechanism of potato thioredoxin gene (StTrxF), StTrxF gene was cloned from potato No. 5 by RT-PCR. The ORF of StTrxF was 549 bp in length and encoded 182 amino acids with a molecular weight of 44.17 ku and a theoretical isoelectric point (pI) of 5.23 with a typical thioredoxin domain. The amino acid sequence deduced from StTrxF gene was 96.02%-59.28% homology to the TrxF proteins of Arabidopsis thaliana, sesame and Cabernet sauvignon. A plant expression vector was constructed and the StTrxF gene was introduced into Arabidopsis by dipping method to obtain transgenic Arabidopsis homozygous lines. The salt tolerance of transgenic Arabidopsis plants was identified by pot experiment. The results indicated that the salt tolerance of transgenic plants was significantly improved. At the same time, under salt stress, the superoxide dismutase (SOD) activity and proline content were significantly increased, and the content of malondialdehyde (MDA) was significantly decreased. These results indicated that the expression of StTtxF gene had significant effect on enhancing the salt tolerance of transgenic Arabidopsis plants by increasing proline content and SOD activity, decreasing MDA content in the transgenic plants, maintaining cell osmotic balance and activating ROS scavenging system. This study would provide an experimental basis for further research of salt-tolerant crops, and a theoretical reference for plant salt-tolerant bio-genetic engineering.Keywords：potato;thioredoxin gene (;Trx;);cloning;Arabidopsis thaliana;salt tolerance0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the function of basic leucine zipper (bZIP) in cassava root development and starch biosynthesis, two members in bZIP family, MebZIP7 and MebZIP9 were cloned and used for a serious of expression analysis in cultivars and wild sub-species under different conditions. Phylogenetic tree analysis ascribed the two members into A subfamily of bZIP family, belonged to abscisic acid response element binding factor (ABF). Sub-cell location confirmed that they appeared inside the nuclear of cell, partly identified their transcription factor feature. Q-PCR screening revealed that the expressions of MebZIP7 and MebZIP9 were significantly higher in storage root and functional leave of the cultivar than those in wild ancestor W14. And both of them were quickly induced by ABA, with 10.7-and 6.3-fold expression in storage root, equally 4.5-fold in leave of cultivar than wild W14 and reached to the peak after one hour and reduced to the initial level after 24 h. Furthermore, their transcriptional activity in timely developing stages under field condition in 3 cultivars and wild W14 were evaluated. It was shown that the MebZIP9 was not only in storage root but also in leaves remarkable high expressed in those 3 cultivars than in the wild W14. But the expression level of MebZIP7 was not significant different except there were higher expressions in storage root of 90 and 150 d of cultivars. This study indicated that the MebZIPs were involved in ABA signal transduction, which was related to starch accumulation in cassava.0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To investigate the optimum nitrogen application rate of buckwheat production for high yield in the Loess Plateau Region, a common buckwheat cultivar Xinong 9976 was used in a field experiment and the effects of different nitrogen fertilizer on the yield, agronomic traits, chlorophyll content and the accumulation of dry matter of buckwheat under four treatments were studied, i.e. no N fertilizer added 0 (N0), 45 (N45), 135 (N135) and 225 kg/hm2 (N225) in 2016 and no N fertilizer added 0 (N0), 90 (N90), 180 (N180) and 270 kg/hm2(N270) in 2017. The results showed that four N fertilization treatments significantly increased the plant height, primary branch number, secondary branch number, number of flower clusters per plant, 1 000-grain weight and seeds number per plant, which led to a significant increase in yield. With the increase of Nitrogen rate, chlorophyll content first increased and then decreased. There was a positive correlation but a trend like a parabola in seedling stage and initial flowering stage between the accumulation of dry matter in various organs of buckwheat and the Nitrogen rate. Therefore, the optimum application amount of Nitrogen was 180 kg/hm2, and more attention should be paid on different proportion and stage of Nitrogen application to ensure production benefit.Keywords：buckwheat;nitrogen fertilizer;dry matter accumulation;yield;agronomic traits2|7|7<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to fill current gaps existed in the description of phenotypic patterns of male resources in persimmon resource descriptive criteria and provide theoretical basis for the evaluation and identification of male perennial persimmon germplasm resources, as well as the new varieties, 13 phenotype indexes of male flower and the pollen morphology of 93 resources were surveyed to analyze the phenotype diversity among persimmon and its related species. The results showed that:1) There were significant differences between persimmon and its related species on the longest stamen length, sepal length and pedicel length of male flower;2) There were strong phenotypes variations within various sources and types, especially male wild resources in ‘Yunjiashan’;3) Phenotypes variations were also found among the persimmon male resources from various sources and types, for which the variations of sepal widthreceptacle height and width were highest;4) The contribution rate of cylinder, stamens, sepals and receptacle were 77.88%, indicating that these were important traits for comprehensive evaluation of the persimmon male resources;5) The length, depth, and interlacing of the pollen surface stripes were different among persimmon and its related species. Besides, there were significantly different (P<0.05) in pollen length between 29 persimmon resources, while those were very significant differences (P<0.01) in both pollen width and surface stripe length. In conclusion, the phenotype of male resources in persimmon was rich and varied, and there were significant differences within various sources and types, and also among the persimmon male resources from various sources and types.Keywords：persimmon;male germplasm resources;phenotype diversity;pollen morphology2|9|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to improve the land utilization rate, a new type of facility strawberry stereoscopic cultivation mode "New H Type " was designed. Strawberry variety ‘Red’ (Fragaria×ananassa Duch.) was planted in two different cultivation modes, "New H Type" and traditional cultivation mode. The light illumination, vegetative growth of the plant, fruit yield and quality, and economic benefit index of these two modes were compared. "New H Type" was comprehensively evaluated in actual production performance. The results showed that the "New H Type" stereoscopic cultivation mode did better than the traditional one. The plant number increased by 20%, input increased by 44.455%, yield increased by 20.240%, total income increased by 35.269% and net profit increased by 25.876% per unit land area. It indicated that "New H Type" stereoscopic cultivation mode was superior to traditional cultivation in improving the land utilization.0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The objectives of this study were to find the expression pattern of the caprine skin genes and investigate the differentially expressed genes in during follicle growth cycle.Skin samples of three female Arbas cashmere goats were colltected at the early stage of each month in whole year.mRNAs of samples belong different month were extract respectively,and transcriptomes were analyzed by Illumina HiSeqTM 2000 high-throughput RNA sequencing.Unigenes with no genome reference were annotated using BLAST search against Nr,GO and KEGG databases.And the expression patterns of differentially expressed genes of different month were analyzed.The result showed that:A total of 55 541 genes were confirmed among 105 854 unigenes discovered.51 078 unigenes were annotated by GO,21 189 unigenes were annotated by COG and 26 201 unigenes was annotated by KEGG database,respectively.Unigenes annotated were found mostly involving in cellular process,metabolic process,biological regulation,regulation of biological process and response to stimulus.Unigenes annotated were mainly with binding and catalytic activity.And by comparison of BLAST with COG database,it was found that the skin genes discovered focused on gene transcription,post-translation modification and signaling mechanisms and were very rare involved in isoenzyme transport and metabolism,cell power,biosynthesis of secondary metabolites,transport and catalytic and nuclear structure.The result from KEGG database annotation showed that skin genes were enrich in MAPK signaling pathway,Wnt signaling pathway,notch signaling pathway,hedgehog signaling pathway,TGF-β signaling pathway,JAK-STAT signaling pathway and focal signaling pathway.By the analysis of transcriptome data,the differentially expressed genes in different month skin's during whole year displayed four times expression changes:The first change occurred between February and March,the second change occurred between March and April,the third change occurred June and July,and the last gene expression change occurred between October and November.The changes of first two are greater than last two,indicating that during the follicle early growth,the skin genes had greater expression change.And the skin genes expression change of follicle growth in the catagen and telogen were smoother and moderate.Keywords：caprine;transcriptomes;differentially expressed genes;skin;cycle of follicle growth0|10|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study was to analyze the expression of KiSS-1 and RFRP-3 genes in the tissues of the hypothalamus-pituitary-gonadal axis in Small Taili Han sheep during different reproductive periods (luteal and follicular periods), and to elucidate the expression pattern of these two genes in estrus conversion of sheep. Small Tail Han ewes at one year-round estrous breed were selected in the study, and Real-time PCR method was used to detect the expression of KiSS-1 and RFRP-3 genes in hypothalamus-pituitary-gonadal axis' tissues during luteal and follicular periods. The results showed that KiSS-1 and RFRP-3 genes were all expressed in ten tissues such as hypothalamus, pituitary and ovary. The expression of KiSS-1 in hypothalamus was significantly higher (P<0.05) than that in other tissues at both luteal and follicular periods. The expression of KiSS-1 in hypothalamus and pineal gland was significantly higher (P<0.05) in follicular period than that in luteal period. The expression of RFRP-3 in hypothalamus and ovary was significantly higher (P<0.05) than that in other tissues both luteal and follicular periods. The expression of RFRP-3 in ovary was significantly higher (P<0.05) in luteal period than that in follicular period. In conclusion, the KiSS-1 and RFRP-3 genes played important roles in sheep estrus regulation. KiSS-1 promoted estrus while RFRP-3 inhibited estrus.Keywords：Small Tail Han sheep;reproductive period;KiSS-1;RFRP-3;tissue expression0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To study the effects of androgen and hydrocortisone on the growth of epididymis epithelial cells in goats, the proliferation of epididymal epithelial cells was detected by microplate reader and androgen receptor (AR) and its expression was detected by Real-time fluorescence quantitative PCR and ELISA in this study. The effects of testosterone and hydrocortisone on the proliferation of caput epididymal epithelial cells and the expression of AR in goat were studied. The results showed that:The concentration of 100 nmol/L testosterone had the highest promoted effect on caput epididymal epithelial cells proliferation, which was significantly different from that of the control group (P< 0.01). The 200 nmol/L hydrocortisone promotes the proliferation of caput epididymal epithelial cells was the best and which was significantly different from that of the control group (P< 0.05), the effect of former is obvious and could be blocked by AR blocker; The effect of both testosterone and hydrocortisone on the proliferation of epididymal epithelial cells was synergistic; The 100 nmol/L testosterone and 200 nmol/L hydrocortisone increased the expression of AR mRNA and protein in the caput epididymal epithelial cells, and was significantly different from the control group (P< 0.05); The expression of AR mRNA and protein in the caput epithelial cells was significantly higher than that in the control group when the two coexisted (P< 0.01). This study indicated that testosterone and hydrocortisone could promote the proliferation of caput epididymal epithelial cells in vitro, showing a concentration dependent manner, and the synergistic effect was shown in the coexistence of androgen and hydrocortisone, which provided a basis for further study on the regulation mechanism of epididymal epithelial cell proliferation and function.Keywords：testosterone;hydrocortisone;caput epididymal epithelial cells;cell proliferation;androgen receptor0|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To study the oxidative stress of goat Sertoli cells (GSCs) during culturing in vitro, a two-step enzyme digestions were used to isolate the testicular cells,then the cells were purified by Tris-HCl treatment. The activity and cell DNA index (DI) were then analyzed. The results showed:The GSCs were polygonal. The cultured GSCs were the most active at fifth day. Most cells contained red lipid droplets in cytoplasm by Oil Red O staining. The GATA4 positive cell rate was 88.27±3.29%. No significant differences in the cell survival rate were observed between the control group and 50 μ mol/L H2O2 group (P>0.05). However, the cell survival rates in the other groups were significantly lower than that in the control group (P<0.05). No significant differences in MDA content and SOD activity were observed between the control group and 50 μ mol/L H2O2 group (P>0.05). The other groups were significantly different from the control group (P<0.05). The DI in 50 μ mol/L H2O2 group was 1.08±0.01, the GSCs in the group did not appear the heteroploid by the cell DNA ploidy test; The DI in other groups was respectively 1.15±0.02, 1.20±0.03, 1.26±0.03, 1.32±0.01 and the cells were all produced the heteroploid. In conclusion, the GSCs were separated, purified, cultivated and identified in the study. After treated with 200 μ mol/L H2O2, the SOD activity of the GSCs significantly decreased, the MDA content significantly increased, and there were significant allopolyploids. The optimized concentration was 200 μ mol/L H2O2. This study provided basis for the establishment of GSC oxidative stress model.Keywords：goat;Sertoli cells;separation and culture;oxidative stress0|7|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to investigate the epidemic situation of intestinal haemorrhagic Escherichia coli from Yak in Tibet area, the virulence genes of 149 of enterohemorrhagic E. coli strains from yak in Linzhi and Lhasa were studied by using PCR detection and phylogenetic analysis. The results showed:The ehxA gene was detected among the 6 pairs enterohemorrhagic E. coli virulence genes originated in yak and the detection rate was 9.40.%. Fourteen strains were then cloned and sequenced by phylogenetic analysis. It was found that enterohemorrhagic E. coli strains were of 99.9% homology, and were 99.0% homology to other strains recorded in GenBank. These results indicated that the Tibetan exist enterohemorrhagic E. coli gene in yak, the main virulence gene was ehxA gene. Linzhi, Ali, Shigatse and Changdu in Tibet were the distribution areas. The enterohemorrhagic E. coli gene was not detected in Lhasa, Shannan and Nagqu. This study indicated that the survey for diarrhea caused by EHEC should be strengthened according to the actual situation. Early pandemic strain warning mechanism should then be established and the drug should be used rationally.0|7|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to reduce the power consumption of screw conveyor and increase its conveying efficiency, its power consumption and productivity ratio were used as evaluation index to establish a regression mathematical model between the indexes and the factors by applying Box-Behnken response surface test method. The structure and working parameters which affecting the conveying performance of the screw conveyor were then optimized. The results showed that when the pitch was 300-355 mm, the rotational speed was 100-140 r/min, and the feeding quantity was 30-70 kg/min, the screw conveyor could meet the requirement of high efficiency and low energy consumption. The primary and secondary order of the effect of the factors on the productivity ratio were feeding quantity, pitch, rotational speed. And the primary and secondary order of the power consumption were feeding quantity, rotational speed, pitch. The pitch of 325 mm, rotational speed of 100 r/min, feeding quantity of 30 kg/min were the best combination factors, power consumption and the productivity ratio were respectively 439.781 W and 0.084 6 kg/W, the power consumption was decreased by 2.44%, and the productivity ratio was increased by 4.96% compared with that before optimization.Keywords：maize straw;rub;screw conveyor;parameter optimization8|9|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：To study the rheological properties of sweet sorghum straw during the compression process, a stress relaxation test of the sweet sorghum compression process was performed by using a multifunctional electronic creep relaxation tester and a self-made compression device. Taking the compressed density, cutting length, moisture content as test factors and rapid stress decay time and balance elastic modulus as stress relaxation characteristics evaluation, three factors and three levels response surface test analysis was conducted by using the Box-Behnken test protocol. The results showed that the stress relaxation model of the sweet sorghum straw was expressed by the five-element equation in the generalized Maxwell model. The fitting coefficients were all above 0.99. The order of each factor to the rapid stress decay time was:Cutting length > moisture content > compressed density. The order of the balance elastic modulus was:Cutting length > compressed density > moisture content; The optimal optimization parameter combination of Sweet sorghum stress relaxation:The compressive density was 637.38 kg/m3, the cutting length was 20-30 mm, the moisture content was 57%, the rapid stress decay time was 4.693 s, the balance elastic modulus was 89.957 kPa. The test results confirmed the best bundled rope and the wrapping films time, which provided the basis for the compressing and binding of sweet sorghum.Keywords：sweet sorghum;straw;compression;stress relaxation;parameter optimization6|8|2<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to solve the problem that target extraction of cotton leaf is not accurate due to the geometric edge grows unevenly under natural conditions, a method for extracting leaf targets of cotton diseases based on improved C-V model is proposed. The algorithm is improved on the basis of conventional model called C-V. The length penalty term and constrained energy term of symbolic distance function are introduced into the energy model, so as to achieve the goal that the length variation of evolution curve is constrained, thus, the extraction process of the target feature for the whole image is completed. First, an initial curve for the segmented images is set by this algorithm, and the segmented images are processed smoothly by Gauss filter operator. Then, the energy equation is established according to the global gray information of the images and the local two value matching information, and the evolution curve is extracted from the evolved level set function according to the discrete form of energy equation. Finally, according to the end condition of the evolution of the level set function, the segmentation result is output. A total of 1 200 images are gathered according to different weather conditions and different backgrounds, and the segmentation performance of the proposed algorithm is evaluated. Experimental results showed that, for the images taken in sunny day, cloudy day and after raining, the contour extraction accuracies of the algorithm are 82.23%, 82.73% and 84.60% respectively. The experimental results demonstrate that, for cotton leaf images that 3 weather conditions (sunny, cloudy, rainy) are mixed with 4 complex backgrounds (white mulch film, black mulch film, straw, soil), its target feature contours can be extracted accurately by this algorithm. It can provide support for the extraction and identification of cotton leaf diseases and insect pests, and provide reference for the extraction of leaves from other plants.Keywords：cotton leaf;complex background;improved C-V model;global information;local information;feature extraction;image segmentation1|8|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to reconstruct the three-dimensional structure of soybean canopy with color information, a multi-source image acquisition system combining PMD camera and color camera was used to acquire the multi-source image of soybean canopy, and the feature points of multi-source images of soybean canopy were studied. By using color image and intensity images as research objects, affine transformation was exploited to realize the transformation from color image coordinate system to PMD image coordinate system firstly, Harris algorithm was then to test the image feature points. Normalized cross correlation was adopted to achieve coarse matching for feature points. In addition, for the purpose of overcoming disadvantages of classic RANSAC algorithm, such as more sampling times and longer time of data validation, an improved RANSAC algorithm was used to realize precise matching, which was based on classification by credibility during stage of matching feature points. We finally accomplished Feature point registration of multi-source image after finishing the steps mentioned above was accomplished. To verify the validity of the image registration algorithm proposed in this study, algorithms of this article were compared to with the traditional image registration algorithm. The test results showed that the correct registration ratios of the sample groups were 83% and 87%, respectively under the circumstance of outside and inside environments, and both of them were better than the classical image registration algorithms, which could meet the need of quick registering feature points of multi-source images of soybean canopies.Keywords：soybean canopies;multi-source images;PMD camera;color camera;registration0|9|0<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Aiming at the problem of complex working condition of farm machinery, variable stress and great influence on the life of structural parts, the load spectrum and fatigue life of the frame of vegetable tool carrier were studied. The stress of the frame was analyzed by finite element method and the measuring points were selected. The load test was carried out by establishing the stress load test system composed of strain gauge, strain adjuster, signal acquisition device,and the stress time history under two typical working conditions of ploughing and road driving was measured. The Fourier transform frequency test and discrete self-function stationarity analysis method were used to determine that the signal conforms to the signal characteristics of random load. Data processing method was adopted to eliminate signal interference factors. Non-parametric rain flow extrapolation was carried out for the measured stress load data. Based on the extrapolation results, the stress load spectrum of the frame was compiled and the fatigue life prediction research was conducted. The results showed that the estimated life of the measuring point 5 with the maximum damage value was 1.043×1013 hours, which met the requirements of service and use. This study provided references for the establishment of load spectrum of agricultural machinery structure and the estimation of fatigue life.Keywords：frame;load test;non-parametric rainflow extrapolation;load spectrum;fatigue damage4|9|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The study the relationship between slope shape and Soil and Water Loss (SWL) taking DEM as main data, Pv index representing profile slope shape is established on the basis of P index, and then taking a catchment in Xixi watershed as the study area to research the relationship between slope shape and SWL. The results show that:1) The rationality of Pv index on representing profile slope shape is confirmed by comparing with previous studies which based on plot or artificial rainfall experiments. 2) The relationship between slope shape and SWL generally shows SWL at uniform slope is the greatest and descends following the direction of convex slope and concave slope. SWL at convex slope is greater than that at concave slope. However, there is an exception that SWL at uniform slope is the smallest when slope gradient lower than 15° and increases following the direction of convex slope and concave slope. 3) The effort of slope shape on SWL is less than slope gradient and greater than slope length, which is the most significant when slope gradient within 25°-35ånd slope length within 30-50 m. 4) The effect of slope shape on SWL is more significant when between micro convex slope and micro concave slope, while the effect at other shapes is more obscure, therefore, transformation slope shape when Pv within -0.4——0.2 or 0.2-0.4 is the most effective for water and soil conservation. The results can provide a novel way to study the relationship between slope shape and SWL, which is also helpful for the prevention and control on SWL.Keywords：soil and water loss (SWL);slope shape;DEM;slope gradient;slope length0|8|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the survey data of households in Luancheng District, Shijiazhuang City, Hebei Province, the agricultural production efficiency and its influencing factors among different types of farmers are investigated by using DEA-Tobit model. The results show that:1) With the increase of scale, the capital input and gross profit per mu increase while labor input as well as net income per mu decrease. It indicates that expanding the scale of cultivated land business leads to more capital-intensive farmland from labor-intensive farmland to some extent. 2) The effects of scale effects on different crops are different. The medium-sized (0.67-3.33 hm2) households have the highest production efficiencies of cereals and walnut, while the small-scale (0-0.67 hm2) households have the highest production efficiency of lawn. 3) For different crops, factors affecting production efficiency are totally different. The education level and labor force are significantly and positively correlated with their production efficiencies of cereals and lawn, while non-agriculture work lead to lower production efficiencies of cereal and lawn. Fertilizer and pesticide inputs increase cereal production efficiency, but decrease lawn production efficiency; There is no significant relationship between age and crop production efficiencies. In conclusion, appropriate land transfer promotion, suitable production scale, agricultural technology increasing would lead to the improvement of agricultural production efficiency.Keywords：operation of farmland;scale agricultural production efficiency;DEA-Tobit;influencing factors1|8|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：In order to obtain urban expansion information accurately, predict urban expansion trend to guide urban planning and optimize urban spatial structure, taken Ordos as study area, and obtain land use classification information by interpreting four years' remote sensing images, including 2000, 2005, 2010 and 2015. And then used area quantity index, expansion strength index to analyze the historical change characteristics and expansion model of urban land use. Finally, based on SLEUTH model to carry out the long time series simulation prediction of urban space expansion. The results show that the growth of urban land in the study period has undergone the development stage of steady-fast and rapid-low speed. In the steady stage, the expansion intensity was moderate, and the city showed a significant extension pattern. In the fast and rapid stage, the expansion intensity was the largest, the city in the north and south direction of the star-like spread pattern, and a new growth center appeared. In the low-speed development stage, the expansion intensity was the smallest, expanded with the extension-internal filling pattern. The model prediction results show that the urban expansion trend in 2020 to 2030 will present the spatial pattern of the smooth docking and strip development of each functional zone, which is based on the internal filling.Keywords：urban sprawl;remote sensing images;land use;SLEUTH model0|8|5<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The aim of this study is to explore factors playing more critical roles in the willingness of the transfer of land management rights of different scale operator. Based on the microeconomic survey data of 926 rice growers in four provinces of Anhui, Jiangxi, Hunan and Hubei and the OLS model, advantage analysis method is applied to compare the relative importance of two dimensions variables of cost & income variables and policy variables to the willingness of land circulation of small farmers and large grain-planting farmers. The results show that income per unit of land promotes small and large farmers to purchase more land. But the cost per unit of land has a significant negative impact on large farmers' will to purchase more land. Besides, only the satisfaction of minimum grain purchase price policy among the governmental factors has a positive influence on small farmers' will to get more land, and both the governmental support for grain planting and the subsidy for agricultural machine have a positive influence. As for small farmers, the will of famers to transfer land management right is mainly affected by the human capital in the family, mainly reflected by the fact that the proportion of agricultural labor and the agricultural income are the key factors. As for the large grain-planting farmers, the will to transfer management right is mainly influenced by how he feels about the agricultural policy environment, among which the subsidy for machines and minimum grain purchase price policy have more significant influence relatively.Keywords：Land circulation willingness;cost-benefit;policy environment;small famers;large grain-planting farmers1|8|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：Based on the theory of neoclassical economic growth, this study constructs a theoretical framework of the spatial convergence analysis of the provincial regional Eco-efficiency. Using the provincial panel data from 2004 to 2015 in China, the provincial ecological efficiency by super efficiency DEA model is measured, and the regional differences of ecological efficiency is analyzed, then the convergence condition of beta through the spatial lag model is tested. The results show that:1) The regional ecological efficiency has been improved year by year and regional difference is obvious, but the differences in most regions are narrowing. 2) There is no convergence in the east area, the middle area, the west area, even the whole country. 3) Considering the spatial cross-correlation, there is β convergence in each area and the whole country. The convergence rate of β is the fastest in the east, the second in the middle and the slowest in the west. However, after introducing some control variables such as urbanization, the convergence rate of β conditions increases, especially in the east and west. 4) Urbanization and marketization promote the improvement of ecological efficiency, and the optimization of industrial structure brings stress to the ecological environment. In conclusion, the improvement of the convergence of ecological efficiency in the region depends on the process of new urbanization construction, the degree of market-oriented reform and the implementation of industrial structure optimization.Keywords：ecological efficiency;regional differences;Sigma convergence;Beta convergence;spatial correlation;SAR model0|11|4<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
Influencing factors and differences of farmers' fallow willingness in heavy metal comtaiminated area
Abstract：Based on the theoretical analysis of farmer's fallowing behavior and the decision-making mechanism, 243 samples of households are analyzed for the features and differences between FFF by the Probit model. The fallowing cultivation pilots in Changsha and Zhuzhou, Hunan Province is surveyed, where the land is contaminated by heavy metal. The results show that:1) The farmer's fallowing willingness is positively influenced by the age of the respondents, the distance of the arable land, the level of the cultivated land and the degree of recognition of the fallowing policy. However, it is negatively impacted by the proportion of the family labor force to the total number of people, the agricultural income before fallowing to the total income and the expected deviation of fallow compensation; 2) The factors that affect farmer's fallowing willingness differ due to the various age groups, the proportion of different family labor force, the distance of farmland to home and the degree of fallow of the different fallow policies. Among them, the fallowing willingness of female farmer households is lower than that of male farmer households. Meanwhile, the older the farmer households are, the more willing they are to fallow. Famers, whose labor force accounts for over 50% in the household, are willing to fallow. The characteristics of farmers and their knowledge of the policies are important factors to FFF under the limited conditions. The influencing factors and differences in farmer's fallowing willingness in heavy metal-contaminated areas will provide decision-making reference for formulating policies to mobilize the farmer's fallowing enthusiasm and improve the arable land fallowing system.Keywords：farmer;fallowing willingness;influencing factors;differences;Probit model0|8|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27- Abstract：In order to identify an effective way to improve the pig production efficiency, based on clarifying the mechanism of the influencing factors of production efficiency, this study conducted an empirical analysis of farrow-to-finish pig farms in China using robust OLS regression and the survey data of Hebei, Liaoning and Beijing. The results showed that:Improving pig farmers' education, strengthening the technology training, promoting the specialization and scale, emphasizing the control of breeding environment and the epidemic disease would promote the pig production efficiency significantly. However, the way of self-made feed, self-produced sow and hire labor would cause loss of production efficiency. The organization level of pig breeding was generally low at present, and cooperative organizations couldn't play an effective role because the construction of social service system was still imperfect. Compared with Beijing, Hebei and Liaoning had comparative advantages in production efficiency and combination of planting and breeding, but Liaoning still has much room for improvement in standardization. In conclusion, it should speed up the construction of vocational education system of pig industry, develop family farms in appropriate scale, improve the standardization level, promote the construction of social service system of pig industry, reduce the disadvantages pig capacity in restricted development regions, and focus on the key development and potential growth regions.Keywords：pig;farrow-to-finish;production efficiency;influencing factor;robust OLS regression2|7|3<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
- Abstract：The geographical location and phonological conditions of Fujian and Taiwan are similar. But their international competitiveness of fishery is different due to different resource endowment and development model between them. By means of Market Share, Revealed Comparative Advantage and Trade Competitiveness Index, this study comparatively analyzed the change of the international market competition in aquatic product of Fujian and Taiwan Province. Using Agricultural location theory and "National diamond model" theory as guide, the international competitiveness influencing factors of Fujian and Taiwan are then empirically analyzed by principal components regression by Principal Component Regression (PCR). On the background of the Fujian Free Trade Area, some policy recommendations of fisheries cooperation between Fujian and Taiwan province are put forwarded in this study at last. The result show that:1) The competitiveness of fishery in Fujian is continuously enhancing while it is declining in Taiwan. Fujian is higher than Taiwan in competitiveness of fishery; 2) Human capital hinders enhancement of international competitiveness of fishery in Fujian. 3) Among the primary factors of production, industrial structure, the internal market demand and human capital hinders enhancement of international competitiveness of fishery in Fujian, industrial structure of fishery is the key to improve the fishery international competitiveness in Taiwan. The main obstruction of adjusting structure is the scarcity of nature resources in Taiwan. 4) Some policy recommendations are put forwarded in this study, which are encouraging Taiwan fishery enterprises to invest in Fujian, increasing the aquatic products in product list under the early harvest in ECFA, establishing the fishery personal training mechanism in cooperation and jointly investing and developing oversea fishery markets.Keywords：fishery;international competitiveness;Fujian and Taiwan;cross-straits cooperation;China (Fujian) Pilot Free Trade Zone0|9|1<HTML><L-PDF> <Meta-XML>Updated：2024-02-27
