Crop Identification Based on TWDTW Method and Time Series GF-1 WFV

【Objective】 Yanqi Basin is an important production base of characteristic agricultural products in Xinjiang, and the planting structure of crops is complicated. In this study, the time series remote sensing data were used to classify and identify crops in the study area, so as to obtain the spatial distribution of different crops and their planting areas, which were the important basis for government sectors to formulate grain policies and economic plans. At the same time, the applicability of time-weighted dynamic time warping (TWDTW ) method in crop classification and the application potential of GF-1 WFV in agriculture were also discussed.【Method】 The normalized vegetation index (NDVI), calculated from the 2018 time series GF-1 WFV data set in Yanqi Basin, Xinjiang, was used to study the crops recognition based on TWDTW method. Sample points of different crops were collected to form standard sequence of NDVI for each crop. The TWDTW similarity matching algorithm was used to calculate the similarity distance between each pixel to be classified and the standard sequence of different crops. The smaller the distance was, the higher the similarity was. The similarity was used to determine the crop type of the pixel, and the final classification result was obtained. At the same time, the classification rules of decision tree were established according to the NDVI curve of time series, and the classification result was obtained by manually setting the classification threshold, and compared with that of the TWDTW method. 【Result】 The classification results of the two methods were very consistent. Peppers were the most widely planted and the wheat was mainly distributed in the northern part of the Yanqi Basin and the 21st Division of the Second Agricultural Division. The distributions of tomato and sugar beet were relatively sporadic. Among the results of planting area, pepper had the largest planting area, followed by tomato, wheat and sugar beet. The accuracy of the classification results of the TWDTW and decision tree methods was verified by the field sample points: The overall accuracy of them were 89.58% and 90.97%, respectively, and the kappa index of them were 0.804 and 0.830, respectively. The classification accuracy of the TWDTW method was slightly higher than that of the decision tree method. 【Conclusion】 Compared with the decision tree classification method, the classification accuracy of the TWDTW method was slightly improved, the classification result was more objective and reliable. The algorithm of TWDTW method was not limited by geographical factors and had strong flexibility and applicability. The experimental results showed that using TWDTW algorithm to identify crops based on the GF-1 WFV data set of dense temporal phase could get better classification results, and it had great application and popularization value in agricultural field.     

阿拉善左旗飞播植物生长发育特性与环境间关系的研究--飞播沙蒿死亡与虫害的关系

飞播沙蒿生长发育到一定年限后即开始大量死亡,其原因之一是钻蛀性昆虫危害.在调查的 856株沙蒿中,感虫株162株,感虫率18.93%.采集到的518头害虫样本中,沙蒿同斑螟、沙蒿刺小卷蛾、沙蒿枝小卷蛾三种共占86.10%,沙蒿圆吉丁虫占13.32%,沙蒿线角蠹蛾占0.58%.沙蒿植株感虫率与其生长年龄、植株地径密切相关.二年生、三年生、四年生和五年生沙蒿植株的感虫率分别为0.12%、5.61%、6.54%和6.66%.     

狂犬病病毒荧光定量RT-PCR快速检测试剂盒的评价及应用

基于目前在我国人群和动物中流行的狂犬病病毒（RV）均属于基因Ⅰ型,在本室所建立的基因Ⅰ型RV荧光定量RT-PCR方法的基础上,组装了可以便捷使用的RV快速检测试剂盒。对4 577份临床样品的检测结果表明,该试剂盒的检测灵敏度达4.68个TCID50,与《狂犬病防治技术规范》规定的套式RT-PCR灵敏度相当,而且稳定性良好,可以冷冻保存8个月以上。所研制的荧光定量RT-PCR快速检测试剂盒具有操作简便、快速、特异性强、灵敏度高、重复性好、稳定性强等优点,既适合单个临床样品的确诊,又适合RV流行病学监测的大规模筛查。     

高效液相色谱法测定牛奶中苯甲酸、山梨酸和糖精钠

建立了采用高效液相色谱法同时测定牛奶中苯甲酸、山梨酸和糖精钠的分析方法,牛奶样品经水提取、离心后直接进样,于230 nm处检测,外标法定性、定量。结果表明:苯甲酸、山梨酸和糖精钠在15 min内能得到较好的分离,检出限分别为0.06、0.07、0.08 mg/kg,样品加标平均回收率在90%～105%之间。     

遮阳网颜色和覆盖时间对菠萝产量及品质的影响

为云南菠萝优质高产种植提供技术依据,采用田间试验研究不同颜色遮阳网(黑色、绿色和蓝色)与覆盖时间(菠萝谢花后60d、45d、30d覆盖)对菠萝日灼率、产量和品质的影响。结果表明:绿色和蓝色遮阳网防日灼效果优于黑网,尤其以蓝色遮阳网效果最佳;覆盖时间对菠萝外观性状及品质影响明显,谢花后60d覆盖蓝色遮阳网菠萝果实的纵、横径大,果眼数适中,果形指数适宜,果实硬度较大,Vc含量高,总酸度低,可溶性糖含量高,外观及品质综合性状好,产量较高。谢花后60d覆盖蓝色遮阳网可实现菠萝的优质高产种植。     

高产抗病小麦丰优3号丰产栽培技术

以播种量(x1)和氮(x2)、磷(x3)、钾(x4)肥施用量为研究对象,采用4因子5水平二次旋转回归组合设计,对高产抗病小麦丰优3号的高产栽培技术进行试验,建立了各因素与产量指标的数学模型y=305.75 11.67x2 14.5x4-9.270 83x22-8.02x24。综合得到丰优3号丰产栽培配套技术措施的优化组合是:施用2 000 kg/667m2农家肥作底肥的基础上,播种量6 kg/667m2,氮施用量22.5 kg/667m2,钾施用量30 kg/667m2,不施磷肥,产量可达314.63 kg/667m2。     

利用GnRH、PGF2α和PRID进行黄牛程序化人工授精

在一个处于自然散养状态下的本地黄牛群体中 ,比较了发情 /排卵同期化并定时人工授精组和仅同期发情处理后适时人工授精组黄牛的繁殖效果。 5 3头健康无病的本地黄牛随机分为 4组 ,试验 组 (Ov Synch法 ) ,注射 Gn RH-PGF2α- Gn RH;试验 组 ,注射 Gn RH- PGF2α- EB;试验 组 ,放置 PRID- PGF2α- EB;对照组 ,注射 PGF2α- PGF2α。其中 ,试验 、 、 组分别在处理结束后 16～ 2 0、2 4、2 4 h进行定时人工授精 ,对照组在鉴定发情后作适时输精。结果显示 :(1)各试验组同期发情率与对照组差异不显著 (P>0 .0 5 ) ,;(2 )试验 、 、 组所有授精牛均分别集中在处理结束后16～ 2 3、2 4～ 2 8、2 4～ 2 8h内完成人工授精 ,而对照组处理牛接受人工授精时间非常分散 ;(3)试验 、 、 组的第一情期受胎率分别为 6 0 .0 %、5 8.3%和 5 7.1% ,与对照组 (42 .9% )之间无显著差异 (P>0 .0 5 )。结果表明 ,试验组 3种程序处理黄牛均可以达到定时人工授精且不降低受胎率的目的。尤其是 Gn RH- PGF2α- EB程序 ,成本低、处理效果好 ,适宜在生产中推广应用