Current issue

• 2016 Vol.32 No.5 Published:19 February 2016

  Expression Pattern of VIP Gene in‘Xingguo Gray Goose’ 2016, 32 (5):  1-4.  DOI: 10.11924/j.issn.1000-6850.casb15070096 Abstract + ( 1017 )   PDF ( 726KB )   ( 442 ) In order to understand the seasonal breeding pattern of‘Xingguo Gray Goose’, the expression of VIP in hypothalamus, pituitary, fallopian tube and ovary of‘Xingguo gray goose’was studied. The control group was in natural photoperiod, and the experimental group was exposed to an artificial program of long and short photoperiods to make the geese breed out of season. The expression levels of VIP gene were tested by FQRT-PCR method in 12 female geese at laying and non-laying period, respectively. The results showed that VIP had different expressions in pituitary, hypothalamus, fallopian tube and ovary between laying period and non-laying period. The expression of hypothalamus and pituitary VIP in non-laying period was higher than that of laying period (P＜0.05).

  Effects of Pollination Methods and Swarm Colony and Structure on Pollination of Hybrid Soybean 2016, 32 (5):  5-9.  DOI: 10.11924/j.issn.1000-6850.casb15090123 Abstract + ( 1553 )   PDF ( 546KB )   ( 585 ) In order to improve outcrossing rate of soybean sterile line, effects of pollination methods and swarm colony and structure on production and quality of hybrid soybean was studied. Different methods to pollination of screen house hybrid soybean in this paper. 3 pollination methods were artificial pollination, natural pollination and bee pollination. 3 kinds of colony were 1 comb, 2 combs and 3 combs of small beehive. Through the statistical analysis of flying bee number and activity pattern in soybean florescence, pod rate of different soybean part, yield characters of parents, the effect of three methods were compared. The results showed that with the increase of comb, flying bee number also increase, the most activity time of bee pollination were concentrated in9:00-13:00. Natural pollination and bee pollination all show the pod rate of upper and middle part higher than the lower. Pod rate per plant, total grain number per plant and yield of bee pollination were highly significant differences between with natural pollination (P<0.01). Hundred-grain weight of bee pollination was decreased. Bee pollination was better than natural and artificial pollination. Pod number per plant was 49.4, total grain number per plant was 96.1, hundred-grain weight was 20.8 g, yield of female parent was 196.6 g in test site of 1 comb bee pollination. Bee pollination improve the female parent production, 1 comb of small beehive can meet hybrid soybean pollination of 20 m2 screen house.

  Review of High-throughput Sequencing Techniques in Studies of constructedwetland Microbial Diversity 2016, 32 (5):  10-15.  DOI: 10.11924/j.issn.1000-6850.casb15090065 Abstract + ( 2322 )   PDF ( 575KB )   ( 921 ) The paper aims to explain the theory of purifying the water body with wetland from the perspective of microbial diversity. The process and principle of the next- generation sequencing technology—highthroughput sequencing technology was analyzed, the advantages and disadvantages of high- throughput sequencing technology applications and the high-throughput sequencing technology application in wetland microbial diversity were summarized in this paper. Meanwhile the broad application value of high-throughput sequencing technology in the diversity and dynamics of the microbial community of artificial wetland was obtained, the high-throughput sequencing results in huge data processing and other issues were pointed out in this paper. Because the high- throughput sequencing technology has unique advantages, it has a great application prospect in the study of wetland microbial diversity.

  CRISPR/Cas9-mediated Genome Engineering and Its Application in Plant Variety Improvement 2016, 32 (5):  16-22.  DOI: 10.11924/j.issn.1000-6850.casb15080140 Abstract + ( 2171 )   PDF ( 727KB )   ( 2534 ) Genome editing using targetable nucleases is an emerging technology for the precise genome modification. The CRISPR (clustered regularly interspaced short palindromic repeats) system, which appeared in 2013, has been modified to serve as RNA-guided endonuclease (known as CRISPR/Cas9). CRISPR/Cas9 has been developed into the third generation of genome editing technology, which is widely used in genome editing among varieties of species including plants with high efficiency and specificity. Furthermore, owing to its simplicity, convenience, and flexibility, CRISPR/Cas9 technology has dramatically accelerated genetic engineering and functional genomics, brought a revolutionary change in every research field of life science studies. This review briefly introduced the emergence and developing of CRISPR/Cas9, described the mechanism of CRISPR/Cas9 mediated genome editing, summarized the application of this tool in crop breeding that aimed at improving crop quality and yield. Finally, we discussed the prospect and application value of CRISPR/Cas9 in crop breeding, so as to provide a theory basis for its use in novel germplasm innovation and crop breeding improvement.

  Screening of β-mannanase High Yield Strain by Ultraviolet Mutation 2016, 32 (5):  23-27.  DOI: 10.11924/j.issn.1000-6850.casb15080135 Abstract + ( 1212 )   PDF ( 664KB )   ( 454 ) In order to provide strains which have a high enzyme yield, the original strain Bacillus licheniformis HDYM- 04 was isolated naturally and then treated with ultraviolet ray. The best mutation condition was determined to expose the strain to the ultraviolet source at 50 cm for 10 s based on the fatality rate. The total strain mutation rate was 76.11%, the positive mutation rate was 54.60%, and the negative mutation rate was 20.92%. A stable β-mannanase producing strain Bacillus licheniformis U2-12 was obtained with the enzyme activity being 242.19% of the original strain. The results can provide superior enzyme production strains for the following test and production practice, and references for studying the effect of ultraviolet ray on β-mannanase gene.

  Influence of Radix paeoniae Rubra Decoction on Secretion of Virulence Factors and Proliferation of Staphylococcus aureus 张鹏鹏,李增顺,宋繁,孙英健 and 穆祥 2016, 32 (5):  28-32.  DOI: 10.11924/j.issn.1000-6850.casb15090074 Abstract + ( 1188 )   PDF ( 1119KB )   ( 559 ) To study the influence of Radix paeoniae Rubra decoction on the secretion of virulence factors (α- Hemolysin, HLα; staphylococcal enterotoxins) and the growth of Staphylococcus aureus in vitro, Staphylococcus aureus was treated with Radix paeoniae Rubra decoction at different concentrations. Then the bacterial growth curve was recorded. Western-blot was performed to investigate the content of HLα, staphylococcal enterotoxins A (SEA) and B (SEB) in the supernatant of bacterial culture solution. The results showed that Radix paeoniae Rubra decoction could not inhibit the proliferation of Staphylococcus aureus (ATCC29213 and ATCC43300) obviously when the concentration ranged from 0 to 10 mg/mL. However, it could decrease the secretion of HLα, SEA and SEB in a dose-dependent manner. The results indicated that there was a potential anti-virulence ingredient in Radix paeoniae Rubra decoction.

  Effect of Drying Detoxification on Cyanide and Total Flavonoids in Cassava Leaves 2016, 32 (5):  33-36.  DOI: 10.11924/j.issn.1000-6850.casb15090035 Abstract + ( 1132 )   PDF ( 534KB )   ( 504 ) The leaves of cassava have rich total flavonoids, and also contain toxic substance——cyanide, which severely restricts the utilization of cassava leaves. To take off the cyanide and retain the total flavonoids in cassava leaves, drying method was used in this study. The drying temperatures were set at three gradients as 65℃, 75℃ and 85℃, and the drying times were set at three gradients as 6 h, 7 h and 8 h, in total, there were 9 experiments. The content of total flavonoids was determined after drying processing of every experiment. The results showed that the optimum condition for taking off cyanide was 75℃ and 6 h. Under this detoxification condition, the content of cyanide was in accord with the National Standard, and the loss of total flavonoids was relatively low. The results could provide a reference for the comprehensive utilization of cassava leaves.

  Study on Combinative Application Technique of Pesticides Against Major Diseases and Insect Pests of Rice 李阿根, and 2016, 32 (5):  37-43.  DOI: 10.11924/j.issn.1000-6850.casb15080128 Abstract + ( 1028 )   PDF ( 655KB )   ( 463 ) This study was designed to explore and optimize the technique of combinative application against the major diseases and insect pests of rice, which would provide data for decreasing the input of chemical pesticides and improving the benefit of rice production. The experiments of combinative application of pesticides were carried out to evaluate seedling quality, controlling effect, population dynamics of spider, yield, cost and economic benefit in early rice, single-season late rice and continuous cropping late rice production, respectively. The results showed that the combinative application of pesticides can effectively control the sheath blight, rice hopper, rice leaf roller and stem borer, reduce 2 or 3 times of spray, decrease 20.88%-56.85% input of pesticides, and can improve seedling quality, promote rice growth, maintain the balance of spider population dynamics, increase of rice yields of 483.30-945 Kg per hm2, increase of benefit of 1186.05-3690 yuan RMB per hm2 at same time. It was effective demonstrated that to implement the plan of combinative application of pesticides can decrease the input of chemical pesticides, realize the agricultural production and gain the satisfied economic, social and ecological benefits.

  Study on Biocontrol of Maize Sheath Blight (Rhizoctonia solani) with Bacillus subtilis Strain 2016, 32 (5):  44-48.  DOI: 10.11924/j.issn.1000-6850.casb15090023 Abstract + ( 1088 )   PDF ( 739KB )   ( 728 ) Jinggangmycin has been approved for controlling the maize sheath blight (caused by Rhizoctonia solani). In order to find a substitute that was safe, efficient and environmental friendly to Jinggangmycin, bacterial suspension of Bacillus subtilis BS-8D which was isolated from sheath of corn plants was used to spray on seedlings and basal part of stem at adult stage. Resistance of BS-8D to rifampicin (BS-8DRif) was tested for its ability to colonize plant roots in soil condition, and screened for its antibiosis in dual culture with other pathogenic fungus. The results showed that BS-8D could control corn sheath blight effectively in greenhouse. BS-8DRif showed that the strain could colonize, propagate and remain high populations for more than ten days in the rhizosphere of corn, and could be transported along with the elongating root and transmitted to stems of maize continuously. By dual culture on PDA medium, BS-8D showed strong ability against Exsero turcicum, Bipolaris maydism and Curvularia lunata. The control test showed BS-8D had potential for further research and development.

  Spatial Change of Peri-urban Area in Urumqi——A Case Study of Gaoxin District 权晓燕,玉素甫江.如素力 and 2016, 32 (5):  49-56.  DOI: 10.11924/j.issn.1000-6850.casb15110144 Abstract + ( 1141 )   PDF ( 2819KB )   ( 447 ) In order to identify the spatial distribution and spatio-temporal variation rules of typical peri-urban area in Northwest China arid region, Gaoxin District of Urumqi was used as an example area in the study. Based on interpreted remotely sensed images of Landsat TM/OLI and statistical data, the authors applied remote sensing, geographic information system spatial analysis techniques, the theory of information entropy, and the method of“break point”to identify the spatial scale of peri- urban area in 2001 and 2013, and analyzed and discussed the spatial distribution change of peri-urban area from the aspects of spatial and timeorder characteristics. The results showed that (1) the chaos degree of landscape disturbance and the construction land proportion index in Gaoxin District of Urumqi had obvious spatial difference; (2) the periurban area distributed in the villages, towns and streets between south core area and north suburb with a star radial divergent form; (3) the spatial shape of the peri-urban area showed obvious shrinkage feature in the southwest and southeast directions; (4) the results had certain theory and application significance.

  Effects of Channelization Farmland Water Conservancy Construction on Agroecological Environment 赵竑绯 2016, 32 (5):  57-66.  DOI: 10.11924/j.issn.1000-6850.casb15080057 Abstract + ( 1090 )   PDF ( 2981KB )   ( 460 ) Agricultural ecosystem is a half-artificial and half-natural complex ecosystem, which is greatly impacted by human activities. Many agricultural ecosystem problems appeared with the promotion and application of channelization farmland water conservancy construction in China. By the methods of field investigation, field experiment and laboratory analysis, studies were conducted from three aspects including effect of the distance to the channel (far, middle, near) on soil available nutrients, effect of different types of channel on water nutrient content and biodiversity of different types of channel. The results showed that (1) soil ammonium nitrogen and nitrate nitrogen showed seasonal variations with the same feature, which was higher in summer and lower in winter, the change of available phosphorus content showed no regularity; the content of soil ammonium nitrogen and nitrate nitrogen in different distance showed the rule of middle＞ far≈ near and far＜middle＜near, respectively; (2) morphological structure of channel had significant effect on the biodiversity, and the biodiversity of animal and plant species showed edaphic channel＞ concrete channel, the edaphic channel had little influence on the habitat and better function of biologic channel which was benefit for the matter and energy flow in agroecological ecosystem; (3) the purifying capacity of edaphic channel was higher than that of concrete channel, by monitoring analysis of pollutant content, the intercept purification effect of edaphic channel was better than that of concrete channel.

  Environmental Impact Assessment of Land Use Planning Based on Ecological Footprint——A Case of Yu City 2016, 32 (5):  67-74.  DOI: 10.11924/j.issn.1000-6850.casb15080156 Abstract + ( 955 )   PDF ( 645KB )   ( 546 ) With the rapid development of the society and economy, it was obvious that the demands and supplies of land was out of balance. Consequently, we should make a proper plan for land use. Land use planning adjusted the structure and layout of land use, which could influence the environment in this area. In order to research the effect on the land use planning, this paper researched in 23 small towns of Yu city. It analysed the total and the per capita ecological carrying capacity from the early planning to the late planning which based on Ecological Footprint. The results showed that:(1) the total ecological carrying capacity in Yu city increased from 120062.95 hm2 in 2005 to 120933.45 hm2 in 2009 and became 123040.46 hm2 in 2020. (2) the per capita ecological carrying capacity in Gucheng town and Yuzhou urban area decreased in the excessive population growth area, while the per capita ecological carrying capacity in other areas increased after the planning. The new implementation of land use planning was beneficial to the environment and increased the total ecological carrying capacity in Yu City.

  A Review of Soil Nutrients of Forest Nature Reserve 2016, 32 (5):  75-82.  DOI: 10.11924/j.issn.1000-6850.casb15090055 Abstract + ( 978 )   PDF ( 592KB )   ( 539 ) Based on a large number of relevant literatures, the authors summarized the effect of environmental factors and human factors on forest soil nutrients in nature reserve, as well as the soil quality assessment and correlation of soil nutrients, to provide references for a deep research on forest nature reserve soil and its protection. The distribution of forest soil nutrients has significant spatial heterogeneity, and its final distribution pattern is the result of joint action of environmental factors, including topography, vegetation, soil type, seasonal change as well soil microorganism, and human factors. In natural ecosystem, environmental factors are the main factors that determine the differences of soil nutrients. Effective human management can promote the accumulation of forest soil nutrients, but improper int erference will cause a significant loss of soil nutrients. Accurate soil quality evaluation can objectively clarify the impact of different soil management practices on soil, contribute to the timely adjustment of management measures. The establishment of long-term soil monitoring stations in forest nature reserves is a good way to master the influencing factors and the mechanism of forest soil nutrients, and can ultimately provide theoretical guidance for a sustainable and healthy operation of forest nature reserve.

  Effect of Soil Salt on Enzyme Activities and Cd Forms Cui Liqiang,Yan Jinlong,Ding Cheng,Chen Tianming and Chen Wei 2016, 32 (5):  83-89.  DOI: 10.11924/j.issn.1000-6850.casb15070170 Abstract + ( 1150 )   PDF ( 953KB )   ( 491 ) In order to study the physiological change of rice and soil enzyme activity and cadmium (Cd) forms under cadmium pollution and salt stress, enzyme activities (soil and plant) and soil Cd form transformation were studied by pot experiment under different salt stress. The results showed that the urease and alkaline phosphatase activity increased by 2.1%-19.5% and 3.8%-64.3% when the salt content increased from 0.3% to 0.5% under the same Cd contamination level. When the soil salt content was higher than 0.5% , the rice seedlings withered. The catalase activity and malondialdehyde content increased with the increase of salt and Cd content. The Cd forms and distribution changed with the change of salt content, the ratios of exchange and square Cd increased with the increase of salt content, the exchange forms and reduction forms of Cd increased with higher salt stress. It indicated that the soil and rice enzyme activities were affected by multi-factors in Cd polluted saline-alkali soil. The synergistic effects appeared on soil and rice with salt and Cd contamination.

  Research Progress of Aeration Impact on Soil Fertility Quality 翟国亮 2016, 32 (5):  90-95.  DOI: 10.11924/j.issn.1000-6850.casb15090083 Abstract + ( 998 )   PDF ( 528KB )   ( 522 ) Soil fertility is an essential attribute of soil, the study on soil fertility quality and its impact factors is important. Aeration is one of the four important factors that affecting soil productivity, and it is attracting increasing attention in the research field. Soil fertility quality evaluation index and soil aeration index were introduced in this paper. Soil aeration could co-ordinate water, fertility and heat conditions, and control soil organic matter decomposition rate and the decomposition products, which could promote high yield. Soil aeration methods included physical, mechanical, chemical, venturi tube and the removable subsurface dripirrigation device system. Many research results showed that aeration treatment could promote crop yield and quality, the mechanism was the promotion of photosynthesis, the accumulation and revolve of photosynthate, the enhancement of root system growth and development and its absorption of mineral elements, and the increase of soil microbial community diversity and enzymatic activity. Aerated equipment with high performance and practicability should be developed to serve agricultural production by being extended from pot culture and microcell study to cropland.

  Effects of Long-term Fertilization on Soil Labile Organic Nitrogen in Arable Moliisols Under Different Organic Matter Levels 2016, 32 (5):  96-100.  DOI: 10.11924/j.issn.1000-6850.casb15080150 Abstract + ( 969 )   PDF ( 536KB )   ( 425 ) The paper aims to illustrate the changes of labile organic nitrogen in arable mollisols under different organic matter levels after long-term fertilization and discuss the evolvement mechanism of farmland mollisols fertility responding to fertilization. Using the long- term experiment on mollisols productivity, the authors investigated the effects of 8-year continuous application of chemical fertilizers on labile organic nitrogen in arable mollisols under different organic matter levels. Farmland mollisols with five different soil organic matter (SOM) levels, 11% (Beian), 6% (Nenjiang), 5% (Hailun), 3% (Dehui) and 1.7% (Lishu), were taken as the study objects. Compared with none-fertilization treatment, the long-term application of chemical fertilizers increased the contents of soil organic nitrogen, including microbial biomass nitrogen, particulate organic nitrogen, and light fraction organic nitrogen (except dissolved organic nitrogen). Soil organic nitrogen, microbial biomass nitrogen, particulate organic nitrogen, and light fraction organic nitrogen all decreased with the decline of SOM. Particulate organic nitrogen contributed the most to labile organic nitrogen in all mollisols. Fertilization had no effect for the correlation between organic nitrogen and active organic nitrogen in the studied mollisols.

  Application Situation and Development Countermeasures of Chemical Fertilizer in Yangzhou 2016, 32 (5):  101-105.  DOI: 10.11924/j.issn.1000-6850.casb15080130 Abstract + ( 872 )   PDF ( 731KB )   ( 436 ) The variation trends of crop yield and chemical fertilizer application in sixty years were studied to know the status of farmland quality in Yangzhou. The results showed that the crop yield increased generally from 2227.5 kg/hm2 to 10732.5 kg/hm2, and the application amount of chemical fertilizer increased first and then decreased. The relationship between the crop yield and the chemical fertilizer application amount were analyzed, and it presented an apparent correlation from 1952 to 1982 (R2=0.8110). The authors elaborated the problems in farmland quality and fertilizer use efficiency, and analyzed the reasons behind these problems. The ountermeasures for improving the farmland quality were proposed, such as gradually improving basic soil fertility and fertilizer use efficiency to guarantee the sustainable development of farmland quality.

  Heavy-metal Pollution Investigation and Health Risk Assessment for Vegetables in Cadmium Exceeded Cultivated Land 2016, 32 (5):  106-112.  DOI: 10.11924/j.issn.1000-6850.casb15080080 Abstract + ( 1174 )   PDF ( 670KB )   ( 481 ) A survey was carried out with the aim to investigate the contamination characteristics of heavy metals in edible parts of vegetables grown in mining area in Yueyang City, the health risk to local consumers was also studied. The concentrations of Cd and Pb in vegetables and soils were analyzed by atomic absorption instrument. The results showed that this region belonged to Cd exceeded soil, and the concentrations of Pb and Cd in edible parts of vegetables exceeded the limit standard. The Pb and Cd contents in vegetables were significantly different, the pollution index and enrichment index of leaf vegetables were higher than that of fruit vegetables. The results of health risk assessment showed that the local inhabitants had higher potential health risks by intake of leaf vegetables. Therefore, this region was not suitable for the cultivation of vegetables, and the cultivated land should be repaired and plantation structure should be adjusted.

  Screening of Soil Stabilization Repair Agent for Lead Contaminated Soil by Battery Factory 2016, 32 (5):  113-117.  DOI: 10.11924/j.issn.1000-6850.casb15060021 Abstract + ( 1063 )   PDF ( 518KB )   ( 520 ) Curing agent screening test was conducted before restoration work of a battery factory. Nine kinds of agents (lime, cement, sodium dihydrogen phosphate, ammonium dihydrogen phosphate, monocalcium phosphate, calcium hydrophosphate, tricalcium phosphate, phosphoric acid, phosphate fertilizer) were used in the lead polluted soil stabilization experiment. In the stability test, different agents were added to lead contaminated soil respectively. For the soil with low level lead, 10% lime, 20% lime, 10% cement, 20% cement, 10% monocalcium phosphate, 10% tricalcium phosphate, 20% tricalcium phosphate, 10% ammonium dihydrogen phosphate, 20% ammonium dihydrogen phosphate and 20% phosphoric acid could achieve the repair target. For the soil with high level lead, 20% cement, 20% calcium hydrophosphate, 10% tricalcium phosphate, 20% tricalcium phosphate, 10% ammonium dihydrogen phosphate, 20% ammonium dihydrogen phosphate, 10% phosphoric acid and 20% phosphoric acid could achieve the repair target. In view of the cost, cement was chosen as the stabilizer in this project, and the appropriate application amount of cement was 10% for low level lead soil and 20% for high level lead soil.

  Variation Characteristics of Main Meteorological Disasters of Jujube in the Hilly Loess Plateau Under Climate Change 2016, 32 (5):  118-124.  DOI: 10.11924/j.issn.1000-6850.casb15080096 Abstract + ( 1089 )   PDF ( 576KB )   ( 430 ) The paper aims to reveal the characteristics of main meteorological disasters in the hilly loess plateau in the context of global climate change, based on daily precipitation data of 12 weather stations from 1971 to 2010 in the hilly loess plateau, the authors analyzed the temporal and spatial distribution characteristics and change regulations of the main meteorological disasters, such as jujube florescence rain, drought in fruit growth period, and the mature period overcast and rainy in the hilly area of loess plateau during the nearly 40 years. The results indicated that the jujube florescence rain and fruit growth period drought showed an increasing trend, and the mature period overcast and rain showed a decreasing trend. The decadal variability of each disaster was relatively stable. The distribution of prone areas of the main meteorological disasters had obvious regional characteristics. The occurrence rate of florescence rain in mid- east and southwest part of the study area was higher than that in other regions. The frequency of the young fruit arid in the west bank of the Yellow River was higher. The mature period overcast and rain in the south was more serious than that in the north.

  Characteristics of Extreme Heavy Precipitation Events and Their Impacts in Qinghai Province 冯晓莉 and 刘彩红 2016, 32 (5):  125-130.  DOI: 10.11924/j.issn.1000-6850.casb15090087 Abstract + ( 919 )   PDF ( 937KB )   ( 503 ) The paper aims to explore the characteristics of extreme heavy precipitation event and impacts in Qinghai province under the background of global warming in order to provide the measures for flood control and mitigation. Based on the daily precipitation data of 40 meteorological stations during the flood season (from May to September) in the period of 1961-2014 in Qinghai province, the spatial distribution and temporal inhomogeneity features of extreme heavy precipitation events were analyzed. Furthermore, the possible impacts of extreme heavy precipitation events were discussed. The results showed that: the intensity and frequency of extreme heavy precipitation events presented an upward trend, and the ratio of extreme heavy precipitation events to the total precipitation increased during the flood season (from May to September) in the period of 1961-2014 in Qinghai Province. The peak of extreme heavy precipitation events came up from mid July to mid August in the mid-eastern part of the eastern agricultural region and southeastern part of Qinghai Province, that the risk of floods, landslides and debris flows disaster increased.

  Doppler Weather Radar Echo Characteristics in a Short-time Heavy Rain on July 15, 2013 in Hohhot 2016, 32 (5):  131-135.  DOI: 10.11924/j.issn.1000-6850.casb15090032 Abstract + ( 1129 )   PDF ( 708KB )   ( 560 ) Based on the Doppler radar data from Hohhot, automatic meteorological station data, FY-2 satellite data, and NCEP 1°×1° 6 h interval reanalyzed data, short-time heavy rain on July 15, 2013 in Hohhot was analyzed in order to accurately forecast the short-time heavy rain. The results showed that: in the large scale circulation background of Lake Baikal cold vortex, the short-time heavy rain was caused by meso-micro scale systems, under the subtropical high and typhoon; water vapor and instable energy were continuously added, because of the continuous transportation of warm and moist air by the southwest stream in front of the trough and the southeast stream between the subtropical high and typhoon; the systematic uplifting, topography and cold air triggered the occurrence and development of meso-micro scale convective systems. The stratiform cloud precipitation echo was obvious in this process, which originated from the south of Yinshan Mountains, and the basic reflectivity was ≤47 dBz. The characteristic of“bull’s eye”was presented and the curve of zero velocity was“S”in the basic reflectivity factor figure. The short-time heavy rain warning can be issued when the mesocyclone and low level jet were found, and the basic reflectivity was≥40 dBz.

  Contrastive Analysis of the Formation Cause of Two Warm-sector Heavy Rainfalls in the Rainy Season in Guangxi 2016, 32 (5):  136-143.  DOI: 10.11924/j.issn.1000-6850.casb15090031 Abstract + ( 1012 )   PDF ( 2397KB )   ( 426 ) The paper aims to deepen the understanding of warm-sector heavy rains and improve the prediction accuracy of such heavy rain. In this paper, based on the onventional observational data, medium scale hourly precipitation data, and NCEP 1°×1° grid point reanalysis data, the contrastive analysis of two warm-sector rainfalls (May 14th-15th, 2015 and June 13th-14th, 2015) in Guangxi was performed. The results showed that: both of the rainfalls occurred in the southward airflow at 850 hPa; there was unstable energy accumulation before the heavy precipitation; strong vertical wind shear at the lower layer of 925-850 hPa accelerated the development of the onvection system; mesoscale surface convergence line was the trigger mechanism of the unstable energy release. The differences between the two rainfalls were: during the rainstorm in May 14th, subtropical high was enhanced and stretched westward; quasi-stationary appeared in mesoscale convection system; convective clouds greatly grew into a mixed precipitation echo featuring cumuliform cloud; the prefrontal ? type high energy tongue was relatively wide; jet stream in the low altitude was strong and stretched high, which facilitated the water vapor transportation in the lower atmosphere and the development of vertical movement. While in the rainstorm in June 13th, subtropical high weakened and retreated eastward;‘train effect’caused continuous precipitation; the extension height of convective echo was relatively low; the rainfall was a mixed precipitation of sheet cloud and cumuliform cloud; and an environment with high humidity of the whole layer reduced the evaporation, which was favorable for the formation of wide-range precipitation.

  Thunderstorm Characteristics Analysis and Thunderstorm Tendency Forecast in Qinghai from 1961 to 2013 2016, 32 (5):  144-151.  DOI: 10.11924/j.issn.1000-6850.casb15080076 Abstract + ( 1006 )   PDF ( 985KB )   ( 493 ) The paper aims to clarify the climatic characteristics of thunderstorm weather variations in Qinghai Province and provide reference for meteorological forecast. The authors analyzed the thunderstorm observation data from April to September of 45 stations in Qinghai Province during 1961-2013, and got the thunderstorm spatial- temporal distribution and variation characteristics in the vegetation growing season by the trend coefficient and the rotated empirical orthogonal function, and then predicted the thunderstorm change in the future using Hurst indexes of R/S method. The results indicated that the average thunderstorm day was 38 days from April to September in Qinghai, and July had the most, the thunderstorm day observed by most of the stations in Qinghai Province presented a significantly decreasing trend; the M- K test indicated that the thunderstorm day had the mutation in May and June starting from 1998. The thunderstorm day was more in the south than that in the north, and decreased from southeast to northwest; and the three main spatial distribution types were northeastern, southern and middle region respectively from April to September. The decreasing trend of thunderstorm in the whole province, northeastern and southern regions would be maintained in the future, and the persistence was strong. The thunderstorm change in the middle region would remain stability.

  Analysis of Spatial and Temporal Characteristics of Drought in Liaocheng Region Based on Z Index 李楠,, and 2016, 32 (5):  152-158.  DOI: 10.11924/j.issn.1000-6850.casb15090002 Abstract + ( 921 )   PDF ( 1760KB )   ( 702 ) The paper aims to understand the natural precipitation deficit and explore the law of drought in Liaocheng. Based on 8 stations’monthly precipitation data in 1970- 2010, Z index method was used to calculate the drought and flood index. Then the drought and flood levels were determined, and drought characteristics of more than 4 decades were analyzed from 2 aspects of time and space in Liaocheng. The results showed that in inter-annual variation, drought and flood appeared alternatively and continuous drought was prone to happen. Overall, there were more droughts than floods. The 3 years and 7 years cycle of droughts and floods were obvious. In spatial distribution, there were more extremely severe droughts in the northeast than that in the southwest, severe droughts happened more often in the eastern area than that in the western area, and there were more droughts in the west than that in the east. The highest drought frequency was found in the northwest.

  Comparative Analysis of Two Drought Indexes Applied in Liuzhou 2016, 32 (5):  159-164.  DOI: 10.11924/j.issn.1000-6850.casb15080153 Abstract + ( 971 )   PDF ( 1274KB )   ( 476 ) The paper aims to find a reasonable drought index for Liuzhou, which will help carry out the research on drought. Based on the daily precipitation data and actual drought information, using the equivalent dry period (EDP) and precipitation anomaly percentage index, the seasonal dry periods from 1961 to 2014 in Liuzhou were categorized and analyzed. Comparing the analysis results with the actual drought occurrence, the findings were as follows: (1) drought frequency and continuing seasonal drought frequency estimated by precipitation anomaly percentage were higher than those estimated by EDP; however, the two had 50% overlap; (2) EDP and precipitation were well correlated in most seasons in Liuzhou, the two indexes were in consistency with temporal and spatial variations, and provided certain rationale to analyze drought in Liuzhou; (3) dry years categorized by precipitation anomaly percentage fitted the actual occurrence of drought better than those categorized by EDP index, and had better correlation coefficients; therefore, using precipitation anomaly percentage to analyze drought in Liuzhou was more scientific and reasonable.

  Research Progress of Allelopathy of Arid Desert Plants in Northwest 2016, 32 (5):  165-172.  DOI: 10.11924/j.issn.1000-6850.casb15090088 Abstract + ( 991 )   PDF ( 581KB )   ( 765 ) To investigate the allelopathy among the plants in the desert ecosystem, this article summarized research achievements in this field in recent years, as well as the reported allelopathy plants, allelochemicals and alleochemicals’release way for the first time. It was considered that: (1) China’s research on desert plants’allelopathy was just at the beginning stage, and allelopathic potential plants were found in the Compositae, Leguminosae, Rosaceae, Scrophulariaceae and Gramineae; (2) the release way of desert plant allelochemicals was mainly natural volatilization, which was related with the growing environment, allelochemicals including alkaloids, flavonoids and terpenoids were identified; (3) finally, key problems of allelopathy plants research in desert ecosystem were pointed out, and the theoretical and practical bases for reasonable protection of desert plants and comprehensive control of desertification were put forward.

  Farmland Soil Mechanized Compaction and Improvement Techniques 2016, 32 (5):  173-177.  DOI: 10.11924/j.issn.1000-6850.casb15100054 Abstract + ( 1155 )   PDF ( 504KB )   ( 508 ) In recent years, soil mechanized compaction is becoming an increasingly prominent problem with the rapid development of agricultural mechanization. Through the analysis of the reasons of soil compaction caused by tractor-unit’s shaft load, pass numbers and operation in wet soil, the soil changes were expounded including physical properties of soil bulk density, hardness, porosity, moisture content and so on, which caused the increase of the tractor-unit operation resistance and the raise of fuel consumption, and a negative impact on crop growth. Some synthesized measures were put forward, including agricultural mechanization techniques such as the operation system of fixed path, the reduction of machine mass, the use of low-pressure tires, avoiding operation in high humidity field and adopting joint operations, as well as agronomic techniques such as increasing soil organic matter and crop rotation, to improve soil compaction, ensure sustainable agricultural development and obtain better results of crop production.

  Assessment and Regionalization of Agricultural Drought Disasters in Anhui Province 2016, 32 (5):  178-183.  DOI: 10.11924/j.issn.1000-6850.casb15090137 Abstract + ( 964 )   PDF ( 606KB )   ( 430 ) To analyze the risk loss of agricultural crops caused by drought, agricultural drought risk in Anhui Province was assessed and regionalized based on data of agricultural disaster and crop sowing area from 1991 to 2012. The results showed that drought was the main agricultural natural disaster in Anhui Province. In the 22 years, drought accounted for 42.1% and 40.1% of agricultural natural disaster affected area and disaster area, respectively. In the cities of Anhui Province, the changes of affected area and disaster area had strong synchronization. Agricultural drought in Anhui Province had short period and high frequency. The drought affected area was generally not more than 60%, and the risk probability was once in 357.1 years. According to the spatial and temporal distribution of the drought risk, Huaibei area and Jianghuai area had higher drought risk than other areas.

  Trend and Hotspot Analysis of Rice Genomics Based on Bibliometric Analysis 2016, 32 (5):  184-193.  DOI: 10.11924/j.issn.1000-6850.casb15080155 Abstract + ( 1022 )   PDF ( 835KB )   ( 468 ) Analyses of status and trends, and hotspots of rice genomics in the world were performed for providing information to rice researchers and decision makers. Based on Science Web database and bibliometrics, top 10 countries, research institutions, authors, journals, disciplines and highly cited articles were analyzed, and SATI were employed to construct the knowledge map. Results showed that, a total of 1537 published articles (1995-2014) from 68 countries were identified, and the number of the published articles showed a stable growth, especially in China. The United States, China, Japan, India and France were the top five countries depending on the number of published papers, among which, the United States, China, Japan also ranked in the world’s top 3 on the basis of total citations. Those research institutes, including Chinese Academy of Science, National Institute of Agrobiological Sciences, University of California (Davis), Cornell University, Huazhong Agricultural University, were main research institutes that featured highly published number and total citations in the research of rice genomics around the world. Results of core authors showed that, there were more core authors in the United States, China, and Japan. From highly cited articles, the United States had 8 articles, and China had 1 article. Therefore, the results proved that the United States, Japan, and China had taken obviously advantages in the research field of rice genomics. The current hotspots in rice genomics was functional genomics and comparative genomics.

  Design and Implementation of Evaluation Platform for Scientific and Technological Innovation Capability of Agricultural Scientific Research Institutions 2016, 32 (5):  194-199.  DOI: 10.11924/j.issn.1000-6850.casb15090008 Abstract + ( 861 )   PDF ( 1144KB )   ( 467 ) In light of scientific theories on system and management, innovation process of agricultural science and technology was analyzed, the evaluation index system and model were built, and the evaluation platform based on multi-source data was developed to provide an appropriate and convenient software tool for decision makers. Then the national-level agricultural scientific research institutions were evaluated. According to the results, the institutions were divided into six types which were science and technology innovation style, science innovation style, technology innovation style, management dominated style, basic capability style and relative inferiority style. Finally, management measures for each style institution were put forward to offer a decisionmaking basis for the government.

  Recognition Degree of Organic Agriculture and Willingness to Pay of Consumers Based on CVM——Evidence from Jiangxi Province 2016, 32 (5):  200-204.  DOI: 10.11924/j.issn.1000-6850.casb15100015 Abstract + ( 1071 )   PDF ( 556KB )   ( 444 ) To study the recognition degree of organic agriculture, ideal price of organic products and the willingness to pay (WTP) for the landscape and culture function of organic farmland, a random questionnaire survey was conducted using the contingent value method (CVM) in Wanzai County, Yichun City and Nanchang City in Jiangxi Province. And the correlation analysis between WTP, recognition degree and the respondents’ social-economic characteristics was conducted. The results showed that the recognition degree was low, only 20.7% of the respondents had a relative good recognition on organic agriculture. The respondents’ideal price on organic products was 1.6 times higher than that of non-organic products. The ideal prices had a significant correlation with recognition degree of respondents (P＝0.034), and had an xtremely significant correlation with gender (P＝0.002) and monthly income (P＝0.002). The average WTP for landscape and education function of organic farmland was 316.7 yuan/(persona). And the WTP for landscape and education function of organic farmland had extremely significant correlation with recognition degree (P＝0.002) and monthly income (P＝0.000). On the basis of these results, enhancing publicity, pricing reasonably, focusing on high-income groups are all effective ways to expand the market of organic agricultural products and services in China.