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61.
扎鲁特旗山地草地土壤含水量动态与气候因子的关系   总被引:1,自引:1,他引:0  
张桂珍  高凯  张丽娟 《草业科学》2015,(9):1399-1404
通过对内蒙古通辽市扎鲁特旗巴雅尔吐胡硕牧业气象站1983-2012年气象数据和山地草地土壤含水量数据分析,揭示土壤含水量的动态变化及其与气候因子之间的相关关系。结果表明,1983-2012年山地草地土壤各层(0-10、10-20、20-30、30-40、40-50和0-50cm)含水量均呈现逐渐降低的变化趋势,草地逐渐旱化;土壤含水量下降过程可以分为3个阶段,第1阶段为1983-1987年,该阶段土壤含水量在15%~30%之间波动,属于土壤含水量的较高阶段;第2阶段为1988-1999年,该阶段土壤含水量在5%~15%范围内波动,属于土壤含水量高(15%~30%)向低(2%~10%)过渡阶段;第3阶段是2000-2012年,该阶段土壤含水量在2%~10%范围内波动,属于土壤含水量较低阶段;土壤含水量与温度和日照时数呈负相关,与降水量、相对湿度、蒸散量呈正相关。  相似文献   
62.
采用高效液相色谱法(HPLC)和紫外分光光度法(UV)测定黑胡椒、胡椒根、市售胡椒粉和用不同浸泡液浸泡脱皮的白胡椒粉中的胡椒碱含量。结果表明:黑胡椒粉、2种市售胡椒粉和白胡椒粉中胡椒碱含量不同;果>根、白胡椒>黑胡椒、盐水浸泡>河水浸泡>醋浸泡、西安胡椒粉>海南胡椒粉。说明不同的胡椒粉胡椒碱的含量不同,这可以为胡椒的质量控制提供比较有用的参考。  相似文献   
63.
The effects of lipid-rich bovine serum albumin (LR-BSA) on the development of porcine blastocysts produced in vitro were examined. Addition of 0.5 to 5 mg/ml LR-BSA to porcine blastocyst medium (PBM) from Day 5 (Day 0 = in vitro fertilization) significantly increased the hatching rates of blastocysts on Day 7 and the total cell numbers in Day-7 blastocysts. When Day-5 blastocysts were cultured with PBM alone, PBM containing LR-BSA, recombinant human serum albumin or fatty acid-free BSA, addition of LR-BSA significantly enhanced hatching rates and the cell number in blastocysts that survived compared with other treatments. The diameter, ATP content and numbers of both inner cell mass and total cells in Day-6 and Day-7 blastocysts cultured with PBM containing LR-BSA were significantly higher than in blastocysts cultured with PBM alone, whereas LR-BSA had no effect on mitochondrial membrane potential. The mRNA levels of enzymes involved in fatty acid metabolism and β-oxidation (ACSL1, ACSL3, CPT1, CPT2 and KAT) in Day-7 blastocysts were significantly upregulated by the addition of LR-BSA. The results indicated that LR-BSA enhanced hatching ability and quality of porcine blastocysts produced in vitro, as determined by ATP content, blastocyst diameter and expression levels of the specific genes, suggesting that the stimulatory effects of LR-BSA arise from lipids bound to albumin.  相似文献   
64.
基于信号博弈的阳澄湖大闸蟹绿色标签市场应用分析   总被引:2,自引:0,他引:2  
水产品绿色标签对消费者来说是高质量的信号,对卖家来说则是卖出高价的资本.但是欺诈行为的存在损害了消费者和其他卖家的利益,扰乱了市场秩序.以阳澄湖大闸蟹为例,通过信号博彝理论,对螃蟹市场中关卖双方的消费行为进行博彝分析,得到了精炼贝叶斯Nash均衡.  相似文献   
65.
The cultivation experiment was carried out to investigate the effects of different proportions of peat soil, perlite, vermiculite and yellow mud on growth of Gesneriaceae species(Chirita gueilinensis, Sinningia speciosa, Lysionotus pauciflorus, Hemiboea henryi, Aeschynanthus acuminatus, Saintpaulia ionantha). The growth traits of each plant growing in 7 different matrix materials were investigated.The plant height, crown width and chlorophyll content of each plant were measured. The results showed that the best substrate ratio was peat soil∶vermiculite=2∶1for C. gueilinensis, L. pauciflorus and H. henryi; peat soil∶perlite∶vermiculite = 2∶1∶1for S. ionantha; peat soil∶vermiculite∶yellow mud=2∶1∶1 for S. speciosa; peat soil∶perlite∶vermiculite∶yellow mud=2∶1∶1∶1 for A. acuminatus.  相似文献   
66.
通过意大利瓦勒拉尼整地系统(由火车型犁和海豚型犁2种犁型构成,其中火车型犁近似水平沟式整地,海豚型犁近似大鱼鳞坑式整地)与常规开沟犁整地效益的对比试验,结果显示:同期覆土层(0~20 cm)的土壤含水量以瓦勒拉尼系统2种整地方式最高,是常规开沟犁整地的1.28倍和1.11倍。火车型犁整地的土壤容重为1.05 g/cm3,常规开沟犁整地为1.08 g/cm3,火车型犁整地后的土壤容重最小。瓦勒拉尼系统的火车型犁整地后的土壤毛管最大持水量是56.12%,远高于未整地的48.44%和普通犁整地的52.12%,分别是后两者的1.16倍和1.08倍。火车型犁整地后文冠果的地径达1.00 cm,是普通犁整地后地径0.42 cm的2.38倍;树高为0.93 m,是普通犁整地后树高0.53 m的1.75倍;保存率由59.30%提高至91.43%,提高了32.13个百分点;海豚型犁整地文冠果4年保存率则提高了13.42个百分点。  相似文献   
67.
In agricultural production, there is contradiction between the cost and accuracy of detection during the course of acquiring soil water content (θ) online. This conflict is one of the core issues of automatic water-saving irrigation technology in agriculture. At the same time, capacitive soil moisture sensor (CSMS) has received considerable attention, for it can acquire θ with low cost and high precision, and meet the application requirements of wireless sensor network (WSN). But CSMS is vulnerable to the soil temperature (Ts) and salinity (Ss) in the measurement process. Therefore, this study took EC-5 sensor for example to establish water detection calibration models of soil temperature and salinity for single sensor, using Least Squares Support Vector Machines on MatLAB (LS-SVMlab) as the tool. On this basis, we explored the spatial variability of Ts and Ss, and then a method, which could be used to calibrate the output signals of sensors in multi-point network, was proposed based on the information-sharing (Ts or Ss) technology of WSN. Through laboratory experiment, we effectively reduced the impact of soil temperature and salinity on the single sensor. In example analysis, we investigated the detection precision and costs under different information-sharing radiuses (r). And the results indicated that the method we proposed based on the information-sharing technology of WSN could successfully calibrate the influence of soil temperature and salinity on sensors in multi-point network, and it was an efficacious approach to determine the balance between the calibration accuracy of moisture sensor and the investment of agricultural production. For example, while the calibration precision of soil temperature and salinity is respectively 1%, the costs can be reduced by 30%.  相似文献   
68.
We previously reported an alfalfa half‐sib family, HS‐B, with improved salt tolerance, compared to parental plants, P‐B. In this study, we conducted additional experiments to address potential physiological mechanisms that may contribute to salt tolerance in HS‐B. Vegetatively propagated HS‐B and P‐B plants were treated with a nutrient solution (control) or a nutrient solution containing NaCl (EC = 12 dS/m). Shoots and roots were harvested at various time points after treatment for quantification of proline, soluble sugar, and H2O2 using spectrophotometers. Subcellular localization and quantification of Na in roots were conducted using a Na+‐specific dye under a confocal microscope. HS‐B produced 86 and 89% greater shoot and root dry biomass, respectively, compared to parental plants, P‐B, under salinity in the greenhouse. Under saline conditions the HS‐B shoots accumulated 115% and roots 55% more soluble sugars than P‐B counterparts. The non‐saline HS‐B shoots, however, showed 72% less soluble sugars than the non‐saline P‐B plants. Under saline conditions HS‐B accumulated 39% less proline in shoots, while roots accumulated 56% more proline, compared to their P‐B parents. HS‐B plants also showed a greater reduction of stomatal conductance under mild saline stress. HS‐B shoots and roots contained 3–4 times less reactive oxygen species (H2O2) after salt treatment compared to P‐B plants. Sodium localization and distribution analysis using Na+‐specific dye revealed HS‐B plants accumulated 88% and 48% less Na+ in stele and xylem vessels compared to P‐B. The study provides insights into the potential mechanisms that may contribute to salt tolerance in HS‐B: maintaining RWC by accumulating soluble sugars while reducing transpiration, maintaining healthy status by reducing oxidative stresses, and preventing salt toxicity by reducing accumulation of Na+ inside root cells and xylem.  相似文献   
69.
在新疆适宜种植甜菜的生态区,通过选择甜菜丸粒化单粒种,在高密度种植条件下,依据不同栽培管理阶段特点采用合理的管理措施,以实现甜菜单产97.5~105.0t/hm2、含糖率15%以上的目标,从而构建甜菜丸粒化单粒种高密高产高糖栽培模式。  相似文献   
70.
Brassica rapa L. is a genetically diverse parent species of the allotetraploid species, oilseed rape (B. napus) and a potential source of drought tolerance for B. napus. We examined the effect of a 13‐day drought stress period during the early reproductive phase, relative to a well‐watered (WW) control, on subsequent growth and development in nine accessions of B. rapa and one accession of Brassica juncea selected for their wide morphological and genetic diversity. We measured leaf water potential, stomatal conductance, water use, and leaf and bud temperatures during the stress period and aboveground dry weight of total biomass at maturity. Dry weight of seeds and reproductive tissue were not useful measures of drought tolerance due to self‐incompatibility in B. rapa. The relative total biomass (used as the measure of drought tolerance in this study) of the 10 accessions exposed to drought stress ranged from 47 % to 117 % of the WW treatment and was negatively correlated with leaf‐to‐air and bud‐to‐air temperature difference when averaged across the 13‐day stress period. Two wild‐type (B. rapa ssp. sylvestris) accessions had higher relative total and non‐reproductive biomass at maturity and cooler leaves and buds than other types. We conclude that considerable genotypic variation for drought tolerance exists in B. rapa and cooler leaves and buds during a transient drought stress in the early reproductive phase may be a useful screening tool for drought tolerance.  相似文献   
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