西安市化肥施用面源污染环境风险评价研究

专项定量评估化肥施用面源污染环境风险,精准识别化肥施用面源污染高风险区域,进而制定有效措施,对面源污染管控工作至关重要。利用西安市1991-2018年化肥施用相关统计数据,全面分析了全市化肥施用时序演变和空间分异特征,并评价了化肥施用面源污染环境风险程度。结果表明：西安市化肥施用量在经历1991-2014年的快速增长后,于2015-2018年出现“四连降”;氮磷钾化肥施用结构比例由1991的1∶0.24∶0.13逐步调整为2018年的1∶0.34∶0.37;1991-2018年间化肥施用强度随时间递增趋势明显,2018年化肥施用强度为1991年的3.60倍;化肥施用环境风险整体增大趋势明显,总肥风险已由1991年的“尚安全”程度上升为2018年的“重度风险”程度。西安市化肥施用面源污染环境风险空间差异明显,其中长安区为“低度风险”区域,临潼区、高陵区和鄠邑区为“中度风险”区域,灞桥区、阎良区和蓝田县为“重度风险”区域,未央区和周至县为“严重风险”区域。在确保农作物产量基础上,西安市应从施肥技术、科技攻关、政策法规等层面入手,制定有效管控措施。     

洱海流域高耗肥作物(大蒜)控氮减磷增效研究

大蒜是洱海流域种植面积大、施肥量大、成本效益相对偏高、面源污染潜在风险较大的高需肥作物,针对这一现状,在洱源县实施增施有机肥、减少氮磷化肥施用对大蒜产量、产值和土壤肥力影响的试验研究。结果表明,控氮减磷和施有机肥,大蒜的产量和产值均较常规施肥高;控氮减磷施肥土壤,全磷、全钾、速效磷较施有机肥增加,有机质、全氮、速效氮、速效钾减少;控氮减磷大蒜的投产比最高,施有机肥的投产比较低。     

化肥减量施用对鲜食玉米产量的影响

针对峨山县化念镇鲜食玉米化肥施用过量,造成生产成本增加、耕地质量下降和农业面源污染,通过鲜食玉米化肥减量施用田间试验,筛选氮、磷、钾施肥最佳配方,基肥、追肥比例,以及施肥时期和施肥方法。试验结果表明,本肥力田块鲜食玉米推荐施肥量为N 495 kg/hm~2、P2O590 kg/hm~2、K2O150 kg/hm2,N∶P2O5∶K2O为1∶0.18∶0.30。本试验可为峨山县鲜食玉米生产提供氮、磷、钾施肥配方和大面积推广化肥减量增产技术提供依据,从而达到节本提质增效,提升耕地质量的目的。     

云南省主要油菜产区施肥现状调查与分析

【目的】摸清云南省主要油菜产区施肥情况以及施肥过程中存在的问题,为进一步规范油菜生产中肥料的投入提供理论依据。【方法】本研究采用农户和农技人员随机抽样调查的方式,进行了2016/2017和2017/2018两个年度的实地走访调查,分析了云南省主要油菜产区当前的肥料投入状况、油菜生产水平及效益等。【结果】施用化肥的农户比例为100%,施用有机肥的农户比例为19.7%;全省油菜生产中氮(全N)、磷(P_2O_5)、钾(K_2O)养分总投入量分别为181.7、81.5、61.0 kg/hm~2,N∶P_2O_5∶K_2O=1∶0.45∶0.34;油菜施肥次数为1～4次,施肥4次的比例占38.1%,追肥2次的农户占61.6%,基氮比例适宜的农户占62.5%。全省油菜平均单产3030 kg/hm~2,纯收益为3758元/hm~2。【结论】在云南省当前油菜生产水平下,应该采取调整化肥和有机肥的施用比例,增加有机肥的施用量,降低N养分的投入,增加P_2O_5和K_2O养分的投入,协调好氮、磷、钾养分比例,进一步加强种植技术和施肥技术培训等措施降低油菜生产成本,增加效益。     

塔河流域农户化肥施用行为影响因素分析——以温宿县实证调查为例

【目的】分析阿克苏地区温宿县农户化肥施用行为的主要影响因素,为引导农户合理施肥,提高化肥利用率,控制和减少流域面源污染的科学决策提供依据。【方法】二元Logistic回归模型。【结果】阿克苏地区温宿县农户化肥施用行为受到文化程度、务农时间、种植规模、是否参加过施肥技术培训、信息获取渠道、农户对化肥施用负面影响所采取的态度、个人施肥习惯、土壤质量下降、病虫害问题等多种因素的影响。【结论】应从加强农户的施肥技术指导、提高农户文化素质、加强施肥技术信息供给、推进农业生产规模化经营等方面规范农户施肥行为,减少农业面源污染。     

有机肥对土壤培肥作用长期定位研究

【目的】揭示有机肥的施用在长期土壤培肥过程中的作用。【方法】设置无肥对照(CK)、减量化肥(N'P')、常量化肥(NP)、有机肥(M)、减量化肥有机肥配施(N'P'M)和常量化肥有机肥配施(NPM)等6个处理,在新疆博乐市进行连续24 a的施肥长期定位试验。【结果】24 a连续施用有机肥处理M、N'P'M和NPM供试土壤有机质、全氮、碱解氮、速效磷、速效钾含量平均较1987年(速效钾1989年)提高34.7%、11.6%、21.6%、153%、14.5%,相反CK、N'P'和NP处理各项指标均有不同程度的降低;2010年施用有机肥处理M、N'P'M和NPM与其对照处理CK、N'P'和NP相比,土壤有机质、全氮、碱解氮、速效磷、速效钾含量平均提高64.8%、60.9%、60.9%、680%、74.1%。【结论】有机肥无论是单独施用还是与化肥配合施用都能够持续提高土壤有机碳、氮含量;施用有机肥能显著提高土壤速效养分水平,在新疆石灰性土壤上对速效磷的提高作用尤其显著。     

与化肥配施的菌肥用量对土壤肥力特性的影响

【目的】探寻适合与化肥配施的菌肥用量,以期指导广东省南雄烟区大田烟草施肥。【方法】利用已分离的有益微生物菌株(包括具固氮解磷功能的固氮菌属Azotobacter sp.菌株x34、具解钾功能的芽孢杆菌属Bacillus sp.菌株jb21、属于光合细菌的胶状红长命菌Rubrivivax gelatinosus菌株sbg11)与有机物发酵配制而成的菌肥,通过烟草大田试验,以不同施用量的菌肥为处理,即CK(清水对照)、T1(化肥)、T2(低用量的菌肥+化肥)、T3(中用量的菌肥+化肥)、T4(高用量的菌肥+化肥),每株按照基肥∶追肥=1∶1的比例施肥。低、中、高用量菌肥分别按照每株基肥10、20、40 g的量施用,所有处理的氮、磷、钾施入总量相等,研究不同用量的菌肥对土壤肥力和土壤微生物的影响。【结果】大田条件下,菌肥+化肥处理能有效提高土壤中有机质含量,显著提高土壤中碱解氮、速效磷和速效钾的含量,增强土壤基础呼吸强度,有效提高土壤中细菌和放线菌数量,降低真菌数量。【结论】中用量菌肥(T3,即每株烟草基肥和追肥分别施用20 g菌肥)增强土壤肥力的效果更明显,可作为该菌肥的推荐用量。     

复硝酚钠与胺鲜酯对棉花化肥吸收率的影响

【目的】研究复硝酚钠(CSN)与胺鲜酯(DA-6)2种植物生长调节剂,分别和化肥复配施用对棉花化肥吸收率的影响。【方法】通过复硝酚硝与胺鲜酯分别和化肥复配施用,采集棉花2叶期、4叶期、6叶期各20株,测定棉株鲜重,干重,以及全氮、全磷和全钾含量,计算棉花3个时期的干物质比、氮吸收率、磷吸收率、钾吸收率,与CK相比较,分析复硝酚钠与胺鲜酯对棉花肥料吸收率的影响。【结果】复硝酚钠和化肥复配施肥后,棉花对肥料的吸收率在2叶期时氮、磷、钾吸收率分别提高了10.76%、0.87%和10.4%。4叶期时氮、磷、钾吸收率分别提高了18.5%、2.34%和24.86%。6叶期时氮、磷、钾吸收率分别提高了31.14%、5.33%和35.56%;胺鲜酯和化肥复配施肥后棉花对肥料的吸收率在2叶期时氮、磷、钾吸收率分别提高了8.31%、0.85%和9.25%。4叶期时氮、磷、钾吸收率分别提高了11.51%、1.48%和15.66%。6叶期时氮、磷、钾吸收率分别提高了27.11%、4.49%和30.31%。【结论】复硝酚钠与胺鲜酯与化肥复配施用,对棉花化肥吸收率有明显的促进作用。     

宝山区水稻生产上化肥减量施用田间效果试验初报

化肥减量施用是防治农业面源污染的重要措施。为评估水稻生产中氮、磷、钾肥减量施用对水稻产量的影响,将开展水稻化肥减量施用的田间肥效试验。结果表明,在水稻生产中,在每667 m~2施纯氮24.27 kg、五氧化二磷2.80 kg、氧化钾3.50 kg的基础上,减氮20%或减肥20%均会显著减少水稻有效穗数,进而降低水稻产量;而减磷20%或减钾20%对水稻产量基本没有影响。     

蔗区土壤连续施用生物有机肥效应研究

【目的】深入了解生物有机肥在甘蔗生产上的增产效果及对土壤肥力的培肥作用,为进一步推进广西甘蔗生产提供参考。【方法】设（1）施生物有机肥;（2）施生物有机肥＋化肥;（3）施等量灭菌有机肥为对照（CK1）;（4）常规施肥（仅施用化肥）为对照（CK2）;（5）空白对照（不施肥,CK3）等5个施肥处理,连续种植3年,在收获期测定甘蔗产量、株高、茎粗、单茎重、蔗汁锤度、蔗糖分和还原糖以及土壤pH值、有机质、速效氮、速效磷、速效钾、缓效钾含量等项目。【结果】所调查蔗区约70%的土壤有机质含量在2%以上。施生物有机肥处理甘蔗平均产量为105694.5kg/ha,比施等量灭菌有机肥对照处理增产26944.5kg/ha,比常规施肥（仅施用化肥）处理增产4099.5kg/ha;施用生物有机肥处理的甘蔗蔗汁锤度和蔗糖分分别为23.1%和16.2%,较施等量灭菌有机肥分别提高0.2%和0.5%,较常规施肥处理分别提高0.8%和1.1%。连续3年施用生物有机肥后,土壤有机质、速效氮、速效磷和速效钾含量均比常规施肥（仅施用化肥）处理高;施用生物有机肥处理甘蔗对氮、磷和钾利用率分别为39.3%、12.8%和52.8%,较施等量灭菌有机肥处理提高18.3%、2.2%和21.6%,较常规施肥处理提高15.0%、4.5%和30.8%。【结论】甘蔗种植区连续3年施用生物有机肥后,土壤有机质、速效氮、速效磷和速效钾含量显著提高;施用生物有机肥能显著提高甘蔗产量和质量以及氮、磷和钾利用率。     

Web2.0,以个人为中心的互联网时代的到来

本文介绍了Web2．0的知识和背景，对Web2．0出现的基础以及典型技术和应用作了阐述，同时对其作出了前景展望。     

Virus Location and Lymphocyte Apoptosis in Lymph Nodes of Piglets Infected with PCV-2

The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ （PCV-2）. Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups： control group （n = 3）, piglets inoculated with PCV-2 alone （PCV-2, n = 3）, and PCV-2 inoculated and KLH immunostimulated group （PCV-2 ＋ KLH, n = 3）. Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. Location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling （TUNEL） and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 ＋ KLH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEL, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 ＋ KLH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 ＋ KLH piglets were significantly higher than those for the control group （P〈0.05 and P〈0.01）. The proliferation index （PI） was 0.17_＋0.01, 0.12_＋0.01 and 0.12_＋0.04 in the control, PCV-2, and PCV-2 ＋ KLH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one o     

市级综合气象信息分析与管理系统的设计与实现

以抚顺地区3个国家基本站50余年气象资料为依托，采用Microsoft Excel工作表实现由气候和农业气候2部分构成的气象与农业综合信息处理系统的基本思路、方法、内容、用途和使用情况。为了实现气候分析及应用的科学化、客观化、系统化、规范化、程序化及连续化的业务目标，按业务流程设计与实现的，包括资料处理、气候趋势模拟、气候预测、气候鉴定、季节性信息化处理、农作物产量预报、气候生产潜力分析等一系列内容在内的系统建设。关键是解决了大量的计算问题，建立了区域性通用模式。     

Multi-variable grey model (MGM (1,n,q)) based on genetic algorithm and its application in urban water consumption

Urban water consumption has some characteristics of grey because it is influenced by economy, population, standard of living and so on. The multi-variable grey model （MGM（1,n））, as the expansion and complement of GM（1,1） model, reveals the relationship between restriction and stimulation among variables, and the genetic algorithm has the whole optimal and parallel characteristics. In this paper, the parameter q of MGM（1,n） model was optimized, and a multi-variable grey model （MGM（1 ,n,q）） was built by using the genetic algorithm. The model was validated by examining the urban water consumption from 1990 to 2003 in Dalian City. The result indicated that the multi-variable grey model （MGM（1,n,q）） based on genetic algorithm was better than MGM（1,n） model, and the MGM（1,n） model was better than MGM（1,1） model.     

Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa

Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.     

不同施肥水平对木薯氮磷钾养分积累、分配及其产量的影响

 【目的】通过比较不同施肥水平下木薯氮磷钾养分积累、分配和产量的差异，探讨粤北坡岗地优质高产木薯氮磷钾养分的最佳用量。【方法】以木薯品种南美119为材料，采用“3414”方案，在粤北翁源进行大田试验。试验共设14个处理。【结果】施肥处理的氮素主要分配到地上部，不施肥处理的氮素则主要分配到根部；不同施肥处理的磷素均主要分配到地上部；不施肥处理和不施钾处理的钾素主要分配到根部，不施氮处理的钾素在根、冠间分配较均衡。在木薯不同生长阶段，植株氮磷钾含量均呈下降趋势，但施氮、磷、钾化学肥料处理植株氮磷钾含量的下降速度小于不施氮、磷、钾化学肥料的处理。处理N2P2K2的氮、磷、钾含量和积累量在各生育期均为最大，不施肥处理（N0P0K0）的氮、磷、钾含量和积累量在各生育期均为最小（P＜0.05）。产量最高的是N2P3K2处理，为22 694.06 kg·hm-2，其次是N2P2K2处理，为21 417.87 kg·hm-2。【结论】木薯产量、氮磷钾养分积累及其在根冠间的分配，对施肥水平高度敏感, 适当比例的氮磷钾肥配合施用既可以显著增加木薯植株的氮磷钾含量和积累量，又可以提高产量。在粤北坡岗地木薯生产中，氮素最重要，在氮素得到满足的条件下，磷素较钾素更重要。在本试验条件下，氮磷钾养分最佳用量为358.80 kgN·hm-2、89.10 kg P2O5·hm-2和187.50 kg K2O·hm-2。     

红苕饲粮中添加铜和/或喹乙醇对猪生产性能及某些血液生化指标的影响

选体重约38公斤的长白(♂)×成华(♀)杂交猪20头,随机分为四组,饲予四种不同的饲粮,研究饲粮中添加铜和/或喹乙醇对猪生产性能和某些血液生化指标的影响。结果表明:基础组、加铜组、加喹乙醇组和两者同时加组全期日增重分别为674、761、796、678克,日采食量分别为2.50、2.65、2.74、2.40公斤,饲料利用率分别为3.73、3.49,3.44、3.54,添加铜和/或喹乙醇对试验第65天血清铜兰蛋白、尿素氨及屠宰率、背膘厚和眼肌面积无显著影响(p>0.05);添加铜使65天血清碱性碱酸酶活性极显著增高(p<0.01),添加喹乙醇有使之升高的趋势,两者同时添加时,碱性酸磷酶活性降低。     

Current progress on genetic interactions of rice with rice blast and sheath blight fungi

Analysis of genetic interactions between rice and its pathogenic fungi Magnaporthe oryzae and Rhizoctonia solani should lead to a better understanding of molecular mechanisms of host resistance, and the improvement of strategies to manage rice blast and sheath blight diseases. Currently, dozens of rice resistance (R) genes against specific races of the blast fungus have been described. Among them, ten were molecularly characterized and some were widely used for breeding for genetic resistance. The Pi-ta gene was one of the best characterized rice R genes. Following the elucidation of its molecular structure, interaction, distribution, and evolution, user friendly DNA markers were developed from portions of the cloned genes to facilitate the incorporations of the Pi-ta mediated resistance into improved rice varieties using marker assisted selection (MAS). However, rice blast is still a major threat for stable rice production because of race change mutations occurring in rice fields, which often overcome added resistance based on single R genes, and these virulent races of M. oryzae pose a continued challenge for blast control. For sheath blight, progress has been made on the exploration of novel sources of resistance from wild rice relatives and indica rice cultivars. A major quantitative trait locus (QTL), named qSB9-2, was recently verified in several mapping populations with different phenotyping methods, including greenhouse methods. The ability to identify qSB9-2 using greenhouse methods should accelerate the efforts on the qSB9-2 fine mapping and positional cloning.     

仙人掌超氧化物歧化酶提取与纯化研究

以仙人掌为试验材料,采用硫酸铵分级沉淀法得到超氧化物歧化酶（Superoxide Dismutase,SOD）粗酶液。然后用Sephadex（葡聚糖凝胶）G-75层析柱层析对粗酶液进行进一步纯化,最后用邻苯三酚法测定酶活力,并对酶活力主要影响因素（包括pH值、温度、抑制剂）进行了研究。结果显示仙人掌SOD酶比活力为751.56U.mg-1。pH值为7.5~8.5时酶活力最大,稳定性也好。温度维持在25~30℃时酶活力最高。由于过氧化氢和氰化钾均能使仙人掌SOD的酶活力显著下降,因而可以初步判断从仙人掌中提取到的SOD是Cu.Zn-SOD。     

锌对镉·汞复合污染下豌豆幼苗生长的影响

以豌豆为试验材料,采用水培方法研究了锌对镉、汞复合污染下的豌豆种子萌发与生长的影响。结果显示,锌浓度≤100.0 mg/L时促进豌豆种子的萌发,锌浓度为200.0和300.0 mg/L时抑制豌豆种子的萌发。当镉、汞的浓度为3.0 mg/L时,100.0 mg/L锌的解毒效应最明显,表现为能够促进镉、汞胁迫下豌豆种子萌发和幼苗生长,降低豌豆幼苗根尖细胞畸变率,提高豌豆幼苗的叶绿素含量及过氧化物酶活性;但当锌浓度≥200.0 mg/L时,与镉、汞协同迫害豌豆幼苗的生长。