不同尺寸蒸渗仪测定作物蒸散的田间试验研究

称重式蒸渗仪测定作物蒸散量（ET）是公认的一种标准测定方法。大型称重式蒸渗仪因单点独立安装而无法进行不同处理的重复试验,小型蒸渗仪则可解决该问题,但目前对于小尺寸蒸渗仪的适用性尚无统一结论。本文利用1m2（SL）、2m2（ML）和4m2（LL）3种不同面积的蒸渗仪在冬小麦（2012年11月21日播种,2013年6月20日收获）和水稻（2013年6月22日移栽,2013年10月28日收获）整个生长季进行连续蒸散量观测,筛选无有效降水日的数据进行对比分析。结果表明：（1）在冬小麦和水稻生长季内,SL（小）蒸渗仪所测蒸散量日内变化均表现出较大的变化幅度,ML（中）蒸渗仪所测蒸散量日内变化趋势均与LL（大）蒸渗仪所测一致,日内变化比较平稳;（2）ML蒸渗仪所测日蒸散量与LL所测结果的相关性最好（P<0.01）;（3）SL蒸渗仪所测水稻日平均蒸散量和蒸散总量与LL接近,所以可将SL蒸渗仪替代LL测定水稻日平均蒸散量和蒸散总量;ML所测冬小麦和水稻的日平均蒸散量及蒸散总量均比LL明显偏小,蒸散总量偏小主要由于拔节后较大的日蒸散量偏差导致。     

不同利用方式红壤磷素有效性的深度变化——以江西省余江县孙家小流域为例

在江西省鹰潭市余江县孙家红壤小流域的典型红壤区随机选取了具有代表性的林地(F)、花生旱地(PU)、新稻田(NP,<30 a)和老稻田(OP,> 200 a),在0~40 cm深度每隔5 cm采集分层土样,分析了土壤全磷(TP)、有效磷(Bray P)、磷素活化系数(PAC)及有机磷(Po)、无机磷(Pi)与各组分磷的深度变化,探讨了土壤pH与土壤有机质(SOM)对红壤磷素有效性的影响。研究结果表明:孙家小流域不同利用方式红壤TP含量大小依次为:老稻田>新稻田>林地>花生旱地;除林地外,花生旱地与稻田土壤TP、Bray P、Pi和Po含量随着土壤深度的增加呈显著降低趋势,且稻田土壤Po含量及其占全磷的比例显著高于林地和花生旱地。花生旱地与稻田0~20 cm土壤中极有效磷(EAP)、中等有效磷(MAP)及EAP、MAP中的无机磷与有机磷的比值均显著高于林地土壤。林地转为旱地和稻田,尤其是长期植稻可以促进土壤非有效磷(NAP)向利于作物吸收的EAP与MAP转化,因而提高土壤磷素有效性。相关分析表明,随着SOM累积量的增加,四种利用方式红壤中EAP、MAP含量均显著提高。     

南黄海族小黄鱼昼夜渔获率差异的统计学分析

利用2004年度东海区重点渔场底曳拖网渔业资源监测资料,从中选用小黄鱼网次渔获率作为指标值,应用LSD方法对南黄海族小黄鱼昼夜渔获率差异进行了统计学分析,以揭示小黄鱼昼夜的活动规律。结果表明,小黄鱼在不同的洄游阶段昼夜网次间渔获率无显著性差异,昼夜无垂直移动现象,常年处于底层,为典型的底层鱼类;在利用底曳拖网船进行渔业资源调查时,无需修正昼夜网次间小黄鱼的渔获率,用获取的调查数据即可估算资源量。     

Effects of CENP-W down-regulation on human glioma U87 cells

AIM: To study the effect of centromere protein W (CENP-W) down-regulation on human glioma U87 cells.METHODS: Small interfering RNA (siRNA) was used to inhibit the expression of CENP-W in the U87 cells. The interference effect of siRNA was evaluated by RT-qPCR and Western blot. The proliferation of the cells was analyzed by MTT assay, BrdU staining and colony formation experiment. Transwell chamber assay was used to detect the invasion ability of the cells. The cell migration ability was measured by a scratch test. The changes of the cell cycle distribution and apoptosis were analyzed by flow cytometry.RESULTS: The results of MTT assay, colony formation experiment and BrdU staining showed that the cell proliferation and colony formation abilities in experimental group were significantly lower than those in control group and negative control group. The results of Transwell and scratch experiments showed that the migration and invasion abilities in experimental group were weaker than those in blank control group and negative control group. The results of flow cytometry analysis showed that the cell cycle distribution in experimental group was arrested in G₀/G₁ phase. The percentage of apoptotic cells in experimental group was higher than that in control group (P<0.05).CONCLUSION: Down-regulation of CENP-W expression inhibits the proliferation, migration and invasion of human glioma cells and promotes the apoptosis of the cells, suggesting that CENP-W may be a potential target of gene therapy for human glioma.     

Screening of lentiviral vectors carrying effective siRNA targeting S1P2 gene

AIM:To screen the lentiviral vector carrying siRNA with higher efficiency of suppressing the sphingosine-1-phosphate receptor 2(S1P2) gene expression in the primarily cultured corpus cavernosum smooth muscle cells of spontaneously hypertensive rats (SHR).METHODS:SHR and SD rats (n=5 each) were used for primarily culturing corpus cavernosum smooth muscle cells.The cells were randomly divided into 6 groups:SHR siRNA-1,SHR siRNA-2,SHR siRNA-3,SHR GFP,SHR control (SHR non-transfection group),and SD control (SD rat control group).Each group had 5 samples with 1.0×10⁵ cells of each sample.At 72 h after transfection (MOI=60) with lentiviral vectors carrying S1P2 siRNA into the SHR corpus cavernosum smooth muscle cells,the expression of GFP was observed under fluorescence microscope.The protein expression of S1P2,ROCK1,ROCK2 and eNOS in the corpus cavernosum smooth muscle cells,and the mRNA expression of S1P2,ROCK1 and ROCK2 were determined by by Western blot and RT-PCR.RESULTS:The transfection efficiency of the corpus cavernosum smooth muscle cells in SHR siRNA-1,SHR siRNA-2,SHR siRNA-3 and SHR GFP groups were>80%.Compared with SHR control group,the mRNA levels and the protein expression of S1P2,ROCK1 and ROCK2 in SHR GFP group showed no remarkable changes,while those in SHR siRNA-1,SHR siRNA-2,SHR siRNA-3 and SD control groups were significantly lower than those in SHR control group (P<0.05).The protein expression of eNOS in SHR siRNA-1,SHR siRNA-2,SHR siRNA-3 and SHR GFP groups were not significantly changed as compared with SHR control group,but that in SD control group was significantly higher than that in SHR control group.CONCLUSION:Three groups of siRNA lentiviral vectors targeting S1P2 inhibit the expression of S1P2 in the corpus cavernosum smooth muscle cells of SHR,and by silencing the S1P2 expression,the expression of ROCK1 and ROCK2 is inhibited.Among them,siRNA-1 has the highest inhibitory efficiency.     

用绵羊小肠液冻干粉测定饲料过瘤胃淀粉小肠消化率方法的研究

本试验旨在以玉米为样本筛选用绵羊小肠液冻干粉测定精饲料瘤胃非降解残渣淀粉小肠消化率的最佳培养条件。分别研究了小肠液冻干粉用量(0.2、0.3、0.4、0.5和0.6g)对16h玉米瘤胃非降解残渣干物质和淀粉小肠消化率的影响;离体培养时间(4、8、12、16、20和24h)对16h玉米瘤胃非降解残渣干物质和淀粉小肠消化率的影响。结果表明,在本试验条件下,绵羊小肠液冻干粉测定玉米瘤胃非降解残渣淀粉小肠消化率的最佳用量为0.45g小肠液冻干粉/0.56g玉米瘤胃非降解残渣,最佳培养时间为12h。利用绵羊小肠液冻干粉测定常用饲料过瘤胃残渣淀粉小肠消化率的方法是可行的。     

降雨类型和水土保持对黄土区小流域水土流失的影响

对黄土区桥子东沟流域的143场次洪水事件水文泥沙数据进行统计分析,并利用K均值分类法划分降雨类型,比较不同降雨类型条件下流域水土流失特征,探讨水土保持治理对不同降雨类型下流域产流输沙的影响。结果表明,次降雨量和最大30 min雨强是影响流域产流输沙的主要降雨特征。降雨事件划分为4种类型:Ⅰ型(小雨量、小雨强)、Ⅱ型(大雨量、大雨强)、Ⅲ型(大雨量、小雨强)和Ⅳ型(小雨量、大雨强)。4种降雨类型下次洪水事件的产流能力和洪峰流量由大到小依次为Ⅱ型、Ⅳ型、Ⅲ型和Ⅰ型。频次最少的Ⅱ型降雨次洪水事件的输沙量最多,Ⅰ型、Ⅲ型和Ⅳ型降雨条件下次洪水事件输沙量的差异不显著,输沙量均较少。水土保持综合治理显著减少了流域径流量和输沙量,其中Ⅱ型降雨次洪水事件减水量和减沙量最多,Ⅰ型最少。     

山区局地气候的小网格研究方法

山区局地气侯除受宏观地形因子影响外，还要受复杂的小环境的影响。为了进一步分析山区局地气侯的差异，更好地对山区自然资源进行开发，应用小网格方法，引入地形因子，修定气候学方程，采用数学方法建立１ｋｍ热量、降水方程；对北京山区进行分析计算的结果表明，它较好地反映了地形对气候资源的影响，基本符合实际情况，月平均温度误差不超过０．６℃，年降水量绝对误差不超过４０ｍｍ，有一定的实用价值。     

宁南黄土丘陵区新型集流造林工程的规划设计与应用

为了探索在小流域土壤侵蚀治理基础上的雨水集蓄利用技术和模式,以半干旱黄土丘陵区国家重点治理小流域为研究对象,遵循坡地水量平衡原理和雨水叠加利用理论,提出了一种新型小流域坡地集雨蓄水工程整地造林技术—“88542”集流水平沟。研究这类工程的内涵、集流潜力及其断面参数。并对工程集蓄的径流通过典型工程应用,分析研究了集流水平沟对土壤水分的恢复调控和土壤的改良效果。结果表明,在半干旱黄土丘陵地区适宜修建“88542”集流水平沟,在0~100 cm土层,与自然坡面相比土壤平均含水量提高5.26%;粉砂粒和粘粒含量提高0.67%和1.53%;有机质提高80%;容重降低11.59%;土壤饱和持水量、田间持水量、毛管持水量、总孔隙度、透气度分别增加了0.63%、2.03%、1.92%、2.71%、5.29%,而且林木的生长量也大幅度提高。     

北京地区春大棚小型西瓜基质栽培优质高效栽培技术

介绍了北京地区春大棚小型西瓜基质栽培优质高效栽培技术,包括品种选择、整枝方式、定植密度、种植模式、水肥管理、病虫害防治等方面.