Current issue

• 2017 Vol.33 No.8 Published:17 March 2017

  Effect of Delayed Sowing Dates on Yield and Quality Traits of Wheat Cultivar‘Yangmai 20’ 2017, 33 (8):  1-4.  DOI: 10.11924/j.issn.1000-6850.casb16040158 Abstract + ( 758 )   PDF ( 534KB )   ( 385 ) In order to adapt the environment change of the wheat production in the middle and lower reaches of Yangtze river, the test set the four late sowing dates with three replication, and grain yield traits, quality traits and starch pasting properties was detected and analyzed. The yield, quality traits and starch gelatinization characteristics of wheat cultivar ‘Yangmai20’ were researched on the different sowing dates. The result showed, as the sowing date delayed, the grain yield, 1000-grain weight, test weight and grain hardness index presented the declining trend significantly, and the highest value was on the optimum sowing date 11/4, and the lowest value was on the sowing date 11/25. However, the protein content, the wet gluten content, and the sedimentation value presented the rising trend. But a similar tendency of peak viscosity, hold viscosity and final viscosity of starch pasting property were found increasing firstly to the highest value and then declining. High yield and good quality of wheat could be achieved under the late planting condition for early sowing.

  SSR-CE/FD Assessment of Guizhou Approved Sugarcane Cultivars and Regional Materials 2017, 33 (8):  5-12.  DOI: 10.11924/j.issn.1000-6850.casb16050053 Abstract + ( 930 )   PDF ( 621KB )   ( 403 ) mbination in local sugarcane cross breeding, SSR-capillary electrophoresis/fluorescence detection (SSR-CE/FD) technology was used to analyze twelve sugarcane genotypes from Guizhou. The SSR data were then calculated using NTsys software. A total of 131 DNA fragments were amplified through PCR by 21 pairs of highly polymorphic SSR primers, of which 90.1% were polymorphic. The number of fragments per primer pair was 6.2. Eleven fragments were genotype-specific fragment of one cultivar (line) from seven cultivars (lines); these genotype-specific fragments could distinguish one cultivar (line) from other six cultivars (lines). The SMC31CUQ primer pair, produced 100% polymorphic alleles, was the highest-resolution primer that could distinguish all the 12 sugarcane genotypes. According to the cluster results of UPGMA program, pairwise similarity coefficients among the 12 molecular identities varied from 0.64 to 0.92. Our study successfully constructed a SSR fingerprint of 131 DNA fragments about 3 cultivars and 9 regional materials in Guizhou Province. The twelve sugarcane genotypes have a narrow genetic base, indicating parental materials with big differences in genetic background should be employed in sugarcane breeding programs in order to broaden the genetic basis among sugarcane cultivars (clones) in Guizhou Province.

  Effects of Different Cultivation Methods on Accumulation, Distribution and Transport of Dry Matter in Potato 2017, 33 (8):  13-18.  DOI: 10.11924/j.issn.1000-6850.casb16050069 Abstract + ( 995 )   PDF ( 641KB )   ( 892 ) To quantitatively analyze the effect of integrated management of irrigation and fertilizers and biodegradable plastic mulch film on accumulation, distribution and transport of dry matter in potato, field experiments were carried out in 2015. The‘Helan 15’(early maturing) potato variety was adopted as experimental material in the study. The effect of integrated management of irrigation and fertilizer and biodegradable plastic mulch film on accumulation, distribution, transport, root-shoot ratio of dry matter, and the contribute rate of different organs to tubers in potato were confirmed. The results showed that: biodegradable plastic mulch film had a promotion effect on dry matter accumulation after starch accumulation stage in potato; integrated management of irrigation and fertilizer could increase the root-shoot ratio in seedling stage of potato, and promote the breeding of healthy seedling; the assimilation quantity from nutritional organs to tubers under the treatments of integrated management of irrigation and fertilizer and biodegradable plastic mulch film were higher than that under the treatments of the conventional water and fertilizer management and plain film, and the assimilation quantity from nutritional organs to tubers in the treatment of WF1 PF1 was the maximum. It indicated that integrated management of irrigation and fertilizer and biodegradable plastic mulch film play a role in promoting the yield of potato tubers.

  Effects of Different Ecological Factors on Growth and Photosynthetic Characteristics of Matteuccia struthiopteris 2017, 33 (8):  19-24.  DOI: 10.11924/j.issn.1000-6850.casb16050051 Abstract + ( 1090 )   PDF ( 950KB )   ( 376 ) To illuminate the physiological mechanism for the resistance of Matteuccia struthiopteris and present theoretical foundation for the cultivation of Matteuccia struthiopteris, potted experiments, photosynthesis tester and agrochemical soil analysis experiments were adopted to investigate the influences of ecological factors, such as soil moisture content, organic fertilizer and light intensity, on the growth and photosynthetic characteristic of Matteuccia struthiopteris. The results showed that Matteuccia struthiopteris seedling had resistance to water stress. When the mass water content of soil was 70%-75% of field capacity, it was optimal for Matteuccia struthiopteris growth, both the net photosynthetic rate (Pn) and transpiration rate (Tr) increased first and then decreased with the increase of soil water content, the trend of water use efficiency (Ew) was conversely. The use of organic fertilizer had positive effects on growth of Matteuccia struthiopteris, composted pig manure was the best and its effect reached the peak at 1500 kg/hm2. Shade measures benefited the growth of Matteuccia struthiopteris, and the optimal transmittance was 30%. The optimal condition for Matteuccia struthiopteris growth was: the mass water content of soil was 70%- 75% of field capacity, pig manure application amount of 1500 kg/hm2 and the transmittance of 30%.

  The Construction of Acetolactate Synthase Gene Integration Expression Vector 2017, 33 (8):  25-30.  DOI: 10.11924/j.issn.1000-6850.casb16050066 Abstract + ( 891 )   PDF ( 961KB )   ( 476 ) In order to learn more about the connections between the expression levels and the yield of the key enzymes in 2,3-BD synthesis route. In this study the Acetolactate Synthase gene (budB) from Klebisella oxytoca HD79 was amplified by PCR with primers designed according to the sequence of budB in Gene Bank, which is 1680bp. The multicopying integrated expression vector pR1SW-budB was constructed using expression vector pRSFDuet-1 as a framework by meas of genetic engineering. The plasmid pR1SW-budB was transformed into Klebisella oxytoca HD79 by electric conversion, then screened through high concentration Kan and PCR for double characterization and transformants were carried out on the determination of enzyme activity. The result demonstrated that integration of expression vector of acetolactate synthase gene was constructed successful. ALS was mostly expressed with the activity of 1.0627 U/mg, which was improved for 4.35 times. That the yield of 2,3-BD as well as lay the foundation of the industrialization of 2,3-BD production in some degree.

  Biosorption of Uranium by Bacillus subtilis and Its Mechanism 2017, 33 (8):  31-38.  DOI: 10.11924/j.issn.1000-6850.casb16110089 Abstract + ( 856 )   PDF ( 2090KB )   ( 516 ) The thesis aims to study the enrichment capacity of uranium by Bacillus subtilis and its mechanism under culture conditions, and thus to provide a basis for the application of this bacterium in uranium pollution control. The effects of initial concentration of uranium, culture time, and inoculation amount on biosorption ability of Bacillus subtilis to uranium were discussed. The mechanism of uranium biosorption by Bacillus subtilis was discussed by FTIR, SEM, EDS, XPS as well as by studying uranium-enriched sites. The results showed that when the inoculation amount was 6%, culture time was 48 h, the biosorption could reach a balance level. When the initial concentration of UO22 was 25-100 mg/L, Bacillus subtilis could grow normally, and enriched the uranium. The cell wall was the main uranium enrichment site of Bacillus subtilis, accounting for about 89% of the total bacterial adsorption amount. SEM and EDS showed that the cell surface of Bacillus subtilis was rough, and uranium deposited on the surface and surrounding areas of Bacillus subtilis. FTIR spectra had showed the characteristic absorption peak of UO22 . And hydroxyl, amine, carboxyl and other active sites of bacterial protein took part in biosorption of Bacillus subtilis to uranium. XPS showed that U (VI) was the main form of uranium adsorbed by Bacillus subtilis. It indicated that in a certain concentration range, Bacillus subtilis had effective enrichment effect on uranium under culture conditions.

  A Review of Nutritional Components in Carya illinoinensis 2017, 33 (8):  39-46.  DOI: 10.11924/j.issn.1000-6850.casb16060100 Abstract + ( 723 )   PDF ( 610KB )   ( 597 ) Carya illinoinensis is a new nutrient-rich food. In this paper, domestic and international researches of pecan in recent years were summarized; nutritional components and healthy effects of Carya illinoinensis were reviewed. Carya illinoinensis nuts mainly contain lipids, phenolic compounds, tocopherols, phytosterols, et al. Carya illinoinensis nuts can protect the health of heart and brain blood vessel and be an antioxidant, while Carya illinoinensis shell is of antioxidation and antianxiety. At the same time, the proportions of fatty acids, phenolic compounds, tocopherols and phytosterols were compared with those of other nuts to provide suggestions for further research on pecan nutritional quality. The authors thought variety breeding and application was important, while research of the health effects was also essential.

  Effects of Pruning Methods on Growth and Fruit Quality of Oil Flat Peach 2017, 33 (8):  47-51.  DOI: 10.11924/j.issn.1000-6850.casb16010007 Abstract + ( 771 )   PDF ( 582KB )   ( 444 ) A comparison of long-shoot pruning and traditional pruning was carried out from 2011 to 2014 on oil flat peach tree of‘Ziyue’,‘Xinyue’and‘Meiyue’. The influence of different pruning methods on photosynthetic rate, tree growth, all kinds of branch, one-year branch germination, fruit-setting rate, yield and fruit quality were studied. The results showed that the photosynthetic rate of oil flat peach by long-shoot pruning increased obviously; the number of 15-30 cm branches was significantly higher than that of traditional pruning; long fruit branches decreased; medium fruit branches, short pod-branch and posy branches increased significantly; the overgrown fruit branches had no big difference. The fruit-setting rate of long-shoot pruning was increased after the 1st and 3rd time physiological fruit-dropping. The yield per plant and the single fruit weight of long-shoot pruning were higher than those of traditional pruning. As to fruit quality, the soluble solids and the high quality fruit rate were increased by long-shoot pruning.

  Effects of a Mixture of Bacterial Manure and Biochar on Soil Environment and Physiological Characteristics of Malus hupehensis Seedlings 尹承苗 and 毛志泉 2017, 33 (8):  52-59.  DOI: 10.11924/j.issn.1000-6850.casb16060131 Abstract + ( 1085 )   PDF ( 863KB )   ( 428 ) By using seedlings of Malus hupehensis Rehd. as objects, this article studies the effects of a mixture of bacterial manure and biochar on the growth of seedlings and on the replanted soil environment. The experiment consisted of five treatments, including a control group (CK), methyl bromide into the cropping soil (T1), 2% biochar into the replanted soil (T2), 500-fold diluted bacterial manure into the replanted soil (T3), and 2% biochar plus 500-fold diluted bacterial manure into the replanted soil (T4). [Result]Results showed that compared with CK, 2% biochar into the replanted soil, 500-fold diluted bacterial manure into the replanted soil and 500-fold diluted bacterial manure 2% Biochar into the replanted soil turned out to increase the plant biomass of the seedling of Malus hupehensis Rehd. to different extent. Among them, the methyl bromide fumigation treatment was the most effective, followed by a mixture of bacterial manure and biochar, and higher than add bacterial manure or biochar treatment alone. Applying 2% Biochar 500-fold diluted bacterial manure into the replanted soil, in September, compared with replanted soil ,the plant height, stem diameter, dry weight and fresh weight of the plant increased by 40.2%, 34.7%, 58.3%, 68.6%, respectively, whereas the root length, root area, root tips, root volume increased 46.5%, 108.0%, 91.0%, 34.3% respectively. A mixture of biochar and bacterial manure T4 significantly increased the root activity of the seedlings of Malus hupehensis Rehd., by 124.2% compared with CK. 2% biochar into the replanted soil, 500-fold diluted bacterial manure into the replanted soil and 500-fold diluted bacterial manure 2% biochar into the replanted soil could increase on the bacteria quantity and reduce on the fungi quantity of the soil under replant condition, respectively. Compared with 2% biochar, 500-fold diluted bacterial manure and a control, bacteria amounts of 2% biochar 500-fold diluted bacterial manure increased by37.1%, 89.8%, 252.4% and fungi amounts reduced by 65.7%, 41.0%, 68.14%, respectively, increasing markedly on the ratio of bacteria and fungi. 2% biochar into the condition soil, 500-fold diluted bacterial manure into the condition soil and 500-fold diluted bacterial manure 2% biochar into the replanted soil increased the soil enzyme activity, respectively. Among them, the amplification of the soil enzyme activity of a mixture of biochar and bacterial manure treatment effect was the most obvious. [Conclusion]As a conclusion, experiments showed that a mixture of biochar and bacterial manure further increased the plant biomass of seeding of Malus hupehensis Rehd., raised the ratio of bacteria to fungi, enhanced the soil enzyme activity, improved the replanted soil environment, and effectively reduced the apple replant diseases.

  Evaluation of Heavy Metal Pollution in Wetland: Research Progress in China 2017, 33 (8):  60-67.  DOI: 10.11924/j.issn.1000-6850.casb16080089 Abstract + ( 858 )   PDF ( 569KB )   ( 531 ) As a kind of important human living environment and ecological system on the earth, the wetland plays an important role in stabilizing environment, protecting species gene and utilizing resources. The wetland is known as the cradle and biological gene pool of nature and human. With more and more serious wetland reduction, functional decline and pollution, domestic and foreign scholars focus their research on wetland continuously, and heavy metal pollution and assessment is one of the key research fields. The author analyzed domestic reports on heavy metal pollution in more than a decade, reviewed present pollution situation and migration characteristics of heavy metals in sediment, water, and soil such as lake, river, delta and coastal wetlands, and summarized the research types, spatial distribution of heavy metal and analysis method, etc. In many research achievements, the mostly used methods were the cumulative index method and potential ecological risk index method.

  Effect of Long-term Application of Different Amounts of Organic Fertilizer on Black Soil Nutrients and Yield 2017, 33 (8):  68-71.  DOI: 10.11924/j.issn.1000-6850.casb16080149 Abstract + ( 688 )   PDF ( 535KB )   ( 429 ) To show responses of crop yields and soil nutrients to different amounts cattle manure application in eroded Mollisols, arable Mollisols of five erosion depths (0, 5, 10, 20and 30 cm) were selected in present study. Three fertilization treatments were conducted in the experiment, including chemical fertilizers alone, chemical fertilizers combined with medium amounts of manure and chemical fertilizers combined with high amounts of manure. Soil organic carbon, nitrogen, phosphorus and crop yields were the parameters that we mainly focused on. In comparisons to chemical fertilizers alone treatment, the application of chemical fertilizers combined with medium amounts of manure and chemical fertilizers combined with high amounts could obviously increase crop yields and soil C, N and P in eroded Mollisols. Furthermore, the application of chemical fertilizers combined with high amounts of manure could significantly increase crop yields and soil C, N and P when compared to the other treatments (p<0.05) and all selected parameters increased the most in erosion depth 0 cm and the least in erosion depth 20 cm. In both fertilization treatments, soil C, N and P decreased with the increasing erosion depth.

  Film Mulching Affecting Soil Moisture Content, Soil Temperature and Peanut Yield 2017, 33 (8):  72-77.  DOI: 10.11924/j.issn.1000-6850.casb16040159 Abstract + ( 759 )   PDF ( 780KB )   ( 498 ) The aim was to study the effect of the different cover modes of plastic film on the soil moisture content , soil temperature in peanut field and peanut growth and development in the semi arid region. The soil moisture in the plough horizon (0-40 cm) and soil temperature in 0-25 cm soil layer were measured in ridge culture under different cover modes of plastic film. The result showed (1) The soil moisture content in 0-40 cm soil layer was affected by different cover modes. The soil moisture content in different soil layer and different ridge position showed parabolic trend with the promotion of growth period. The soil moisture content in 0-40 cm soil layer of ridge side was significantly lower than that of furrow in peanut seedling stage. The decreasing range of soil moisture content from seedling stage to flowering stage in furrow was larger.(2)The soil temperature was affected by increasing the daily maximum temperature under different cover modes. The soil temperature was strongly affected by cover modes during early growth stage of peanut. The highest daily maximum temperature was up to 36.2℃ of multi ridge covering. The soil temperature was less affected by cover modes during late growth stage. The soil temperature in 0-10 cm soil layer was not significant affected by cover mode after flowering, while remarkably affect the soil temperature in soil layer below 15 cm during 14:00～18:00. The soil temperature of L3 was highest , which of L0 and L1 were lower. (3)The soil temperature at 14:00 was significantly affected by mulching cultivation. The soil average daily temperature of plough horizon increased 0.5~2.4 ℃ at seedling stage under mulching cultivation, and the greatest temperature difference appeared at 15 cm soil layer in the middle of ridge. (4) Mulching can improve the yield 16.81%~37.17%, water use efficiency increased 37.42%~17.03%.The ridge film mulching and double row cultivation of peanut is an economical, efficient, easy cultivation method.

  The Application Effect of Biological Bacterial Fertilizer on Peanut 2017, 33 (8):  78-83.  DOI: 10.11924/j.issn.1000-6850.casb16050109 Abstract + ( 828 )   PDF ( 506KB )   ( 379 ) Peanut is one of the four major oil crops, the main foreign exchange earning agricultural products of China, and it is also one of the agricultural commodities with strong international competitiveness. This study was carried out during 2014-2015 in the Chengdu plain area by using the high-yield new strains cultivate by Economic Crops Research Institute, Sichuan Academy of Agricultural Sciences. The field properties, yield, nutritional ingredient elements, dry matter of root and variation of soil of peanut were comparatively studied by setting 8 experiments using different gradient and mixed fertilizer, different components of fertilizer with biological manure fertilizer, farmyard manure and fertilizers. The result showed that the effect by using biological manure fertilizer with ordinary fertilizer is the best, but the application effect of using biological manure fertilizer alone or in combination with farmyard manure is relatively poor. The highest yield of peanut can be increased by 28.2%, sugar content of peanut increased by 18.9% by using biological manure fertilizer with ordinary fertilizer. The dry matter of root of peanut increased by 25.8%. The contents of N, P, K and organic matter in soil can be increased by 45.7%, 58.2%, 38.8% and 67.2% compared with the control. Biological fertilizer can improve soil, increase crop yield, enhance crop resistance, improve quality and so on. So, it has good prospects of application in peanut planting industry.

  Fertilizer-saving and Yield-increase Potential of Main Grain Crops in Shanxi Province 2017, 33 (8):  84-90.  DOI: 10.11924/j.issn.1000-6850.casb16080055 Abstract + ( 696 )   PDF ( 878KB )   ( 617 ) The planting area, productive yield, fertilizer usage and nutrient efficiency trend in main grain crops (Spring maize，summer maize and winter wheat) growth between 2004 and 2013 in ShanXi was summarized in this paper, and the potential of crop fertilizer was analyzed. Results show that compared to in 2004, in 2013 the grain crops sown area increased by 48.4%, the total grain production increased by 23.6%, the amount of fertilizer usage increased by 29.5% at the mine time, simultaneous growth of the total grain yield increase is mainly contributed by growth of maize’s planting area and yield. Over the 10 years, corn acreage increased by 48.4%, and total yield increased by 51.2%. However, the grain yield stagnated. Through analyzing the production rate of fertilizer, fertilizer-saving rate and other potential indicators in the grain production in Shanxi, it was shown that, with premise of the stability of potassium fertilizer application in maize and wheat production, 17 million tons fertilizer usage can be reduced, fertilizer saving potential can reach to 22%. Under the condition of saving 20% fertilizer, and with high yield and high efficiency technology applied, the goal of grain yield increases by 20% and nitrogen fertilizer production increases by 10% can be achieved. This can make grain production in Shanxi green and more productive.

  Allelopathy Autotoxcity Effect of Successive Cropping Obstacle and Its Alleviate Mechanism by Intercropping 2017, 33 (8):  91-98.  DOI: 10.11924/j.issn.1000-6850.casb16050045 Abstract + ( 998 )   PDF ( 654KB )   ( 643 ) Successive cropping obstacle is a typical negative plant-soil feedback phenomenon, which has long plagued the development of agricultural production, and the occurrence mechanism and control measures of successive cropping obstacle have been research focuses of domestic and foreign scholars. Autotoxcity is one of the occurrence mechanisms of successive cropping obstacle, the accumulation of autotoxins affects nutrient absorption, photosynthesis and enzyme activity, then inhibits crop growth. Meanwhile, autotoxin decreases soil microbial activity and diversity, enhances the growth of pathogenic bacteria and soil- borne diseases by changing microflora, then leads to an increased degree of soil sickness. Intercropping accords with the idea of sustainable development of modern agriculture, using plant allelopathy can provide nvironmental, economical and effective approaches to control successive cropping obstacle. The authors analyzed resistance enhancing from crop nutritional and hysiological aspects, clarified the mechanism of successive cropping obstacle alleviation by intercropping from the interaction of rhizosphere microorganisms, autotoxins and pathogens. The results could provide references for the understanding of underground ecological processes in intercropping and the release of successive cropping obstacle, to formulate reasonable intercropping mode. The study is helpful to reveal the feedback mechanism between the ground and underground biodiversity.

  Comparison of Farmland Nutrients Loss in Two Small Basins of Danjiangkou Reservoir 2017, 33 (8):  99-103.  DOI: 10.11924/j.issn.1000-6850.casb16080071 Abstract + ( 855 )   PDF ( 577KB )   ( 459 ) The Donggou villagers group of Taozhuang River basin and Zhengwan village of Tiewa River basin were as representatives to study their common land types--corn and orchard whose nutrient loss characteristics and differences of nutrient concentration in surface runoff; SCS model were applied to estimate the runoff depth of the two types of land use together with rainfall data, on this basis, the nutrients loss in normal flow year were estimated. Result is that the loss of TN, NO3-N, NH3-N and their content from runoff in the corn in Taozhuang River basin were lower than that in Tiewa River basin, but the loss and content of CODMn and TP were higher than that in Tiewa River basin; For orchard, the nutrients loss and content in runoff in Taozhuang River basin were all higher than that in Tiewa River basin ; The order of nutrients loss and content were consistent in the two types of farmland in Taozhuang River basin , roughly CODMn > TN > NO3 -N> NH3 - N > TP, which indicated organic fertilizer were used more than nitrogen and phosphate fertilizer, the order was followed in orchard in Tiewa River basin, but the order in corn was TN > NO3 -N > CODMn > NH3 - N > TP, which showed nitrogen fertilizer were used more than organic and phosphate fertilizer. Conclusion: it’s time to adopt scientific and reasonable fertilization way, such as testing soil for formulated fertilization, to reduce non-point source pollution in farmland , improve the utilization rate of fertilizer and increase crop output.

  Analysis and Control Measures of Pollutants into the Shuifeng Lake 2017, 33 (8):  104-111.  DOI: 10.11924/j.issn.1000-6850.casb16050067 Abstract + ( 597 )   PDF ( 701KB )   ( 410 ) To suppress the deterioration of the water quality of Shuifeng Lake and control the pollution effectively from the source, this study carried on an investigation of the pollution load distribution and the evaluation of the ecological security of the basin, aiming to provide theoretical evidence for the water environmental management through the analysis of the source, components and distribution of the pollutants into the lake. The results showed that: non-point source including livestock and poultry breeding and planting contributed much more than industrial point source in the discharge of COD, TN and TP; and the amount of pollutants into the Shuifeng Lake exhibited obviously seasonal characteristic; the ecological security index of the Shuifeng Lake was evaluated to be in the safe zone based on the eco-security assessment with the model of “drive-pressure-state-impact-response”(DPSIR), however, pollution control was in urgent need due to the water quality deterioration. Therefore, the study put forward that pollution control measures should be emphatically launched from the inflowing rivers, livestock and poultry breeding, and crop planting based on the actual situation.

  Spatial and Temporal Characteristics of Drought-flood in Chamdo Based on Standard Precipitation Index (SPI) 2017, 33 (8):  112-118.  DOI: 10.11924/j.issn.1000-6850.casb16050076 Abstract + ( 680 )   PDF ( 1094KB )   ( 321 ) Drought-flood is one of the major natural hazards in Chamdo. The paper aims to study the spatial and temporal characteristics of drought-flood changes in Chamdo, and offer scientific basis for reducing the loss caused by regional drought- flood disaster, rational utilization of water resources and ecology barrier construction. Based on the monthly precipitation data of 7 meteorological stations in Chamdo during 1981- 2015 and the standard precipitation index (SPI ), the spatial and temporal characteristics of drought-flood in Chamdo were analyzed. The results indicated that: the characteristics of drought-flood showed an obvious stage characteristic, drought-flood manifested alternately during 1981-1995, the flood was more severe from 1996 to 2004, and drought was more frequent from 2005 to 2015; the precipitation in spring and summer showed a weak increasing trend, and the precipitation in autumn had a weak decreasing trend; the occurrence of drought in spring and summer tended to decrease weakly, while in autumn tended to be more severe, there was no obvious change in winter; there was a relative consistence in variation of drought-flood in the northern part, the central part and the southern part during 1981-2001, but there was a big difference since 2002; the most drastic drought-flood variability occurred in the middle 1980s, and in the early 21st century, the variability was the minimum; the variability in three parts was consistent with that of Chamdo in the mass; the change rate was high in the southern part since 2011, and the characteristics of drought-flood showed a frequent alternation.

  Regionalization and Assessment of Solar Energy Resource of HulunBuir in Recent 30 Years 2017, 33 (8):  119-123.  DOI: 10.11924/j.issn.1000-6850.casb16040023 Abstract + ( 868 )   PDF ( 976KB )   ( 449 ) The paper aims to objectively evaluate the solar energy resource potentiality. The authors used the global radiation data of two radiation stations of Hailar and Fuyu in 1985-2014, and the sunshine data of other 15 stations in Hulunbuir, adopted solar energy resource assessment method and standards to calculate the global solar radiation of non-radiation stations in Hulunbuir, analyzed spatio-temporal distribution features of global solar radiation, and calculated various parameters of solar resources in Hulunbuir. The results showed that: the solar energy resource was very rich or abundance, stable or relatively stable in most areas, and had more days for development and utilization in Hulunbuir, especially in the western and southeastern regions.

  Agricultural Carbon Emission and Spatiotemporal Distribution in Shanxi Province 2017, 33 (8):  124-129.  DOI: 10.11924/j.issn.1000-6850.casb16080078 Abstract + ( 780 )   PDF ( 851KB )   ( 425 ) With the increase of greenhouse gases (GHG) concentration, global warming becomes an urgent environmental problem. The authors studied the total amount, spatiotemporal distribution and constituent ratio of agricultural carbon emission in Shanxi Province based on agricultural statistical dataset and statistical yearbook, combined with questionnaire survey and field interview. The results showed that: (1) the total amount of agricultural carbon emission increased year by year from 2005 to 2010, with the an annual growth rate of 5.36%; (2) Yuncheng, Linfen and Jinzhong generated more carbon emission than other cities, and the emission intensity in unit area was higher in Taiyuan, Jinzhong and Changzhi; (3) the agricultural carbon emission showed zonal distribution and the difference of nature and economy had certain effect on it; (4) the open burning of straws accounted for more than 50% of the total carbon emissions, and then was fertilizer application. The results could provide data support and measures for agricultural carbon emission mitigation in Shanxi Province.

  Effect of Different Culture Methods and Densities on Sheep Preantral Follicles Development 2017, 33 (8):  130-134.  DOI: 10.11924/j.issn.1000-6850.casb16050040 Abstract + ( 654 )   PDF ( 1198KB )   ( 261 ) The paper aims to investigate the optimal culture condition of sheep preantral follicles and provide evidence to explore the law of sheep follicle growth by studying culture methods. Experiment 1: traditional culture method and agar medium culture method were used to investigate the influence on the growth of sheep preantral follicles; experiment 2: sheep preantral follicles cultured alone and cultured in group were used to investigate the influence of different culture densities on the growth of sheep preantral follicles. The results showed that there was no significant difference between traditional method and agar medium method on the increase of diameter and survival rate after 3 days culture (P >0.05); but after 6 days culture, the increase of diameter and survival rate of preantral follicles cultured by agar medium was extremely and significantly higher than the follicles cultured by traditional method (P <0.01); when cultured by agar medium, during the 6 days, there was no significant difference between follicles cultured alone and follicles cultured in group on the increase of diameter and survival rate (P >0.05). The results confirmed that agar medium culture method was qualified to sheep preantral follicles culturedin vitro ; there was no significant influence of density on sheep preantral follicles culturedin vitro .

  Application of Organic Trace Elements in Chicken Production 2017, 33 (8):  135-139.  DOI: 10.11924/j.issn.1000-6850.casb16060050 Abstract + ( 772 )   PDF ( 483KB )   ( 595 ) Organic trace elements, having stable chemical structure and high biological value, can enhance disease resistance and stress tolerance of chicken and are environment friendly. We reviewed the biological characteristics of organic copper, iron, manganese, zinc and selenium, and summarized their application in chicken production. Compared with inorganic trace elements, organic trace elements are obviously better in utilization and absorption rate, improving production performance and egg quality of chicken. But the contradiction between rapid industrial development of trace element and relative lagging production level leads to a lot of problems in production and application of organic trace elements. This article provides a reference for finding the optimum application dosage of organic trace elements in chicken production, reducing trace element residues in chicken products and protecting environment.

  Problems and Countermeasures of Agricultural Mechanization in Hilly Area 2017, 33 (8):  140-143.  DOI: 10.11924/j.issn.1000-6850.casb16050019 Abstract + ( 621 )   PDF ( 485KB )   ( 428 ) Agricultural mechanization in China will develop into a higher stage by 2020. To achieve the aim, mechanization in hilly area should have a substantial progress. At present, there are some problems in agricultural mechanization in hilly area, including disadvantageous infrastructure, inadequate attention, insufficient supplement, immature policies and so on. To deal with these problems, government departments, authoritative units, agricultural machine cooperative organizations, scientific research institutions and agricultural machine companies should work together and adopt a series of practical approaches, including upgrading infrastructure, strengthening technical innovation, improving organization system, optimizing industry structure and so on. Different local conditions should be taken into account and the above countermeasures should be applied to realize a rapid, sustainable and healthy development of agricultural mechanization in hilly area

  Corn-soybean Crop Rotation Remote Sensing Monitoring Technologies 2017, 33 (8):  144-153.  DOI: 10.11924/j.issn.1000-6850.casb16080068 Abstract + ( 738 )   PDF ( 2488KB )   ( 380 ) Based on 2014—2015 Google Earth images, multi-temporal OLI and RapidEye image data of Bei’ an, Heilongjing Province, a corn- soybean crop rotation remote sensing monitoring operational technology process was established by employing remote sensing visual interpretation methods. The major technical links included five steps of data pre-processing, accuracy acquisition of land location and area information, crop type identification, accuracy verification and changes statistics. The result showed that the total area of the project zone was 4528.7 hm2, with a total of 447 land parcels; among which, 193 land parcels of corns in 2014 were rotated to soybean in 2015 with a total area of 3794.4 hm2 and 65 land parcels of soybean in 2014 were rotated to corn in 2015, with a total area of 88.0 hm2; through the verification by using one by one investigation method, the land parcel accuracy reached 100.0%. The technical methods proposed by this paper had relative high accuracy and monitoring efficiency on land parcel measurement, and it could be used as the verification technology for examining the implementation of the policies on crop planting structure adjustment.

  Investigation and Research on Traditional Farming Knowledge and Technology of Hakka Terrace in Chongyi 2017, 33 (8):  154-160.  DOI: 10.11924/j.issn.1000-6850.casb16050057 Abstract + ( 714 )   PDF ( 1313KB )   ( 550 ) Chongyi Hakka terracing is one of the three largest terraced landscape, reservation and exploitation of Hakka farming knowledge and technology in Chongyi has an important significance not only for the study of human civilization but also has a unique role to show the diversity of world culture. As a living fossil of ancient Chinese farming civilization, Hakka terrace shows great achievements about the ancient agriculture in our country, protecting and developing Hakka terrace, is good better for people to have a better understanding of the ancient Chinese farming civilization and promote the development of modern agriculture. [Method]The research around construction and management, the traditional tillage types, traditional rice cultivation techniques, and traditional farming tools, and other aspects of the topic in Chongyi Hakka terrace, [Result]visited and full investigated of "Chongyi Hakka rice terraces for agricultural system of traditional farming knowledge and technology system", collected the Hakka traditional farming tools, rice cultivation, terrace water resources management which is related to the content of the picture and text materials, it is good for comprehending the problems of the local government and farmers" understanding of "Chongyi, Jiangxi Hakka terrace" traditional farming technique and traditional farming protection for technology.S[Conclusion]At the same time, the development and protection of the terraces will promote the tourism value and cultural value of the terraces, and promote the regional economic development and ecological environment protection and sustainable development.

  Income Report on Herdsmen in High Altitude Area: Taking Guoqing Village in Lhasa City as an Example 2017, 33 (8):  161-164.  DOI: 10.11924/j.issn.1000-6850.casb16050081 Abstract + ( 1080 )   PDF ( 487KB )   ( 405 ) To understand the income of herdsmen who live in the high altitude area, we investigated 179 herdsman households in Guoqing Village, Dangxiong County, Lhasa City, Tibet Autonomous Region from 2009 to 2014. The investigation contents included the breeding situation of domestic animals, family labors and annual income per capita. The results of the survey showed that the herdsman income and the amount of domestic animals were continually increasing, but the distribution of annual income per capita showed that households with low and middle income accounted for a large proportion. Based on these situations, we put forward suggestions such as improving quality and effectiveness of grassland husbandry and increasing employment rate of herdsmen with low income.