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71.
基于原野服务器的远程树木直径测定的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
以卫星遥感为主的资源环境监测,由于受云层分辨率等限制,一直以来其应用重点主要在"监"上,本文介绍一种近年来刚刚兴起的能够进行远程监、控、测集网络与传感器于一身的结合体--原野服务器.首先对其定义、种类、外业设置及远程监控操作做了简单的介绍,然后尝试利用原野服务器传回的图像,通过立体视觉技术重建远隔地树木的胸径,得到了较为满意的结果,从而实现了不到现地便能够测量直径的目的.  相似文献   
72.
3S技术在林业资源调查上的应用研究   总被引:2,自引:0,他引:2  
全球定位系统(GPS)、地理信息系统(GIS)以及遥感技术(RS)合称为3S技术,已在各个领域得到广泛应用。本文从实践角度对3S技术在林业资源调查上的应用进行了分析和探讨。  相似文献   
73.
Plant height is closely related to seed yield of soybean. The goal of this study was to identify important loci affecting soybean plant height using meta‐analysis based on a reference physical map. Plant height related to QTLs was mapped across eight years with a RIL population by WinQTLCart v2.5. 182 QTLs related to plant height of soybean from database and our research were collected, and each QTL was projected onto the soybean physical map by software BioMercator v2.1. The confidence interval of meta‐QTL ranged from 0.09 to 5.07 Mb, and the mean phenotypic variance ranged from 4.9% to 73.0%. Furthermore, 4,259 candidate genes were located in these consensus QTLs, and 40 of them were involved in the plant growth and stem elongation and annotated as plant hormone signal transduction (pathway ID ko04075) in KEGG pathway. These results would lay a foundation for fine mapping of QTLs/genes related to plant height and marker‐assisted selection for breeding in soybean.  相似文献   
74.
为获得针对番鸭细小病毒VP3蛋白的多克隆抗体,根据已发表的该病毒基因序列设计一对引物,利用PCR扩增出VP3基因,将其克隆到原核表达载体p ET-32a,转化感受态细胞BL21(DE3)。经IPTG诱导后,SDS-PAGE检测重组蛋白。将重组蛋白切胶免疫BALB/c小鼠,制备抗番鸭细小病毒部分结构蛋白的多克隆抗体。结果显示成功获得VP3基因,构建的原核表达重组质粒成功表达预期的重组蛋白,免疫小鼠获得的多克隆抗体能与番鸭细小病毒及VP3蛋白反应。表明制备的多克隆抗体可用于MDPV的检测,并为进一步研究MDPV奠定了基础。  相似文献   
75.
本试验旨在研究饲粮中维生素K3添加水平对五龙鹅生长性能、屠宰性能及养分表观利用率的影响。试验分为2个阶段。1~4周龄阶段,选用1日龄五龙鹅360只,随机分为6个组,每个组6个重复,每个重复10只鹅。Ⅰ组为对照组,饲喂基础饲粮(维生素K3含量1.23 mg/kg),Ⅱ~Ⅵ组在基础饲粮中分别添加1、2、4、8、16 mg/kg的维生素K3。5~16周龄阶段,选用28日龄五龙鹅324只,随机分为6个组,每个组6个重复,每个重复9只鹅。A组为对照组,饲喂基础饲粮(维生素K3含量1.18 mg/kg),B~F组在基础饲粮中分别添加2、4、8、16、32 mg/kg的维生素K3。试验期16周。结果表明:1)经回归分析得出,1~4周龄阶段五龙鹅饲粮中添加4.81 mg/kg维生素K3,平均日增重最大;5~16周龄阶段饲粮中添加11.59 mg/kg维生素K3,平均日增重最大。2)与对照组相比,1~4周龄阶段,饲粮中添加4 mg/kg维生素K3能显著或极显著提高鹅的全净膛率和腹脂率(P0.05或P0.01);5~16周龄阶段,饲粮中添加8 mg/kg维生素K3能显著或极显著提高屠宰率、半净膛率、全净膛率和腿肌率(P0.05或P0.01)。3)与对照组相比,5~16周龄阶段,饲粮中添加8 mg/kg维生素K3能极显著提高钙的表观利用率(P0.01),显著提高干物质、粗蛋白质、粗脂肪、中性洗涤纤维、酸性洗涤纤维和磷的表观利用率(P0.05)。由此可见,本试验条件下,1~4周龄和5~16周龄五龙鹅饲粮中维生素K3适宜添加水平分别为4.81和11.59 mg/kg。  相似文献   
76.
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry  相似文献   
77.
有益元素对水稻种子萌发的生理效应   总被引:2,自引:0,他引:2  
罗海波 《种子》2000,(3):24-25
将水稻种子浸于从0到10mg·L-1不同浓度梯度的亚硒酸钠溶液中,对其生理指标进行测量可溶性糖含量、呼吸强度及发芽率等.结果表明在低浓度亚硒酸钠溶液浸种的前提下,亚硒酸钠对以上各项生理指标均有促进作用,而高浓度亚硒酸钠溶液浸种,表现出较大抑制作用,同时.由于植物体内复杂多样的同功酶系统的存在,在一定范围内对亚硒酸钠的毒害作用有某种程度的适应与调节能力.  相似文献   
78.
The aim of the present study was to determine the effect of dietary lysozyme levels on growth performance, gut health and non‐specific immunity of weanling piglets. A total of 150 weanling piglets were allocated to six treatments. The piglets were fed the same basel diet supplemented with 0, 30, 60, 90 and 120 mg/kg lysozyme as well as antibiotics for 28 days. From day 14 to day 28 of dietary treatment, piglets fed 90 mg/kg lysozyme had greater average daily gain than piglets fed control diet. During the whole experimental period, piglets fed 120 mg/kg lysozyme tended to have greater average daily gain than piglets fed control diet. Compared with piglets fed control diet, piglets fed diets containing antibiotics and 90 mg/kg lysozyme had greater villus height to crypt depth ratio in duodenum and jejunum. Additionally, dietary supplementation of 60 and 90 mg/kg lysozyme as well as antibiotics enhanced the phagocytic activity of peritoneal macrophages in piglets. In conclusion, dietary lysozyme can accelerate the growth of weanling piglets by improving gut health and non‐specific immunity and supplementing 90 mg/kg lysozyme is as effective as antibiotics (20 mg/kg colistin sulphate + 50 mg/kg kitasamycin) in improving the growth performance of weanling piglets.  相似文献   
79.
Nitrogen (N) leaching from soil into water is a significant concern for intensively grazed forage‐based systems because it can cause a decline in water quality and is a risk to human health. Urine patches from grazing animals are the main source of this N. The objective of this study was to quantify the effect that forage type and gibberellic acid (GA) application had on N leaching and herbage N uptake from urine patches on perennial ryegrass–white clover (RGWC), Italian ryegrass and lucerne. A lysimeter study was conducted over 17 months to measure herbage growth, N uptake and N loss to water beneath each of the three forage types with the following treatments: control, urine (700 kg N/ha) and urine with GA (8 g GA active ingredient/ha). Compared with RGWC (205 kg N/ha), N leaching losses were 35.3% lower from Italian ryegrass (133 kg N/ha) and 98.5% higher from lucerne (407 kg N/ha). These differences in leaching loss are likely to be due to winter plant growth and N uptake. During the winter months, Italian ryegrass had higher N uptake, whereas lucerne had lower N uptake, compared with RGWC. The application of GA had no effect on N leaching losses, DM yield or N uptake of forage treated with 700 kg N/ha urine.  相似文献   
80.
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