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1.
施肥对香根草定植缓苗期影响研究   总被引:4,自引:0,他引:4  
王秀荣  卢小良 《草地学报》2004,12(3):256-257,260
香根草(Vetiveria zizanioide)是禾本科岩兰属多年生草本植物。原产于东南亚,印度和非洲,是理想的水土保持绿篱植物,其地上部簇生成丛,等高密植能形成致密的绿篱带,拦截被冲刷的泥沙和地表径流,深达2~3m的须根系统可牢固地固持土壤,并能吸收一般作物无法吸收到的深层土壤水分和养分。目前,世界上有100多个国家和地区在栽培和利用香根草。我国南方各省从1988年以来一直在推广种植香根草篱作为水土保持措施,具有很大的发展前景。但香根草定植后缓苗期较长,初期长势弱,尤其是在贫瘠的坡地上,严重影响其水土保持的效果。  相似文献   

2.
香根草研究与应用进展   总被引:17,自引:3,他引:14  
对香根草Vetiveria zizanioioles的植物学特性、生态适应性、繁殖技术、种植管理技术及在农业、工程、环保、经济等领域的研究与应用状况和发展前景进行了系统总结,并且对香根草研究与推广中一些值得注意的问题进行讨论.  相似文献   

3.
王学文  刘鸿雁  何进 《草业科学》2023,(8):2028-2037
研究植物对复合重金属污染矿区土壤重金属吸附效应对重金属污染防治具有重要意义。本研究在复合重金属污染矿区种植4种密度的香根草(Chrysopogon zizanioides),分析不同密度香根草在复合污染矿区的生长及其对土壤重金属汞(Hg)、砷(As)、锑(Sb)、铅(Pb)的吸收和富集特征。结果表明:香根草根系长度和根表面积、地上部和根系生物量随种植密度和种植时间的增加而显著增加(P <0.05);香根草地上部重金属含量均小于地下部重金属含量。随着种植密度的增加,土壤As、Pb和Sb的含量显著下降且土壤As含量降低幅度最大,土壤Hg含量无显著变化。随着种植时间的延长,土壤As、Pb和Sb含量呈下降趋势但土壤Hg含量无变化;香根草对Hg、As、Pb、Sb均有富集作用,其富集潜力表现为Sb> Hg> Pb> As。种植180 d,单位面积香根草对Hg、As、Pb、Sb的吸收量分别为9.24、7.24、13.9、1.04 mg;种植360 d的重金属吸收量比180 d分别提高25%(Hg)、44%(As)、44%(Pb)和42%(Sb)。Pearson相关性分析表明:...  相似文献   

4.
种子繁殖香根草植株的生物学特征及其病虫害初报   总被引:7,自引:4,他引:3  
香根草Vetiveria zizanioides种子繁殖植株经过9个月生长,其分蘖数平均每株21个,抽穗率10%~30%,淡黄色的种子长1.5~2.5mm,宽0.6~0.8mm,呈长椭圆型;种子千粒重0.291g;平均结实率18.92%。结果表明,香根草种子繁殖植株基本与亲本保持一致。此外,其上出现蚜虫危害。  相似文献   

5.
植物生长调节剂对香根草定植缓苗期的影响   总被引:2,自引:1,他引:2  
进行了香根草的土壤盆栽及营养液栽培试验,结果表明,几种植物生长调节剂浸根对香根草的地上部、根系生长及根系形态指标等方面都产生不同程度的影响.吲哚丁酸(IBA)能较好地增加新根数量,对地上部生长及根系形态指标有较好的促进作用.从总体来看,几种植物生长调节剂对香根草的作用效果与一般作物相比均不理想.  相似文献   

6.
紫色土坡耕地香根草根系的固土抗蚀效应   总被引:1,自引:0,他引:1  
本试验以坡度3°和25°下的自然生草和香根草(Vetiveria zizanioides)为研究对象,采用室内直剪试验和原状土冲刷试验,分析紫色土坡耕地上香根草根系的固土抗蚀效应。结果表明,1)香根草根系改变了土壤结构,土壤容重与根长密度、根表面积密度极显著负相关(P0.01),与根重密度显著负相关(P0.05),土壤含水率与根长密度、根表面积密度显著正相关;2)土壤抗剪强度与根重密度、根表面积密度极显著正相关,与根长密度、含水率显著正相关,土壤抗冲性指数与根重密度、根长密度和根表面积密度极显著正相关;3)同级荷载(100、200、300、400 k Pa),土壤抗剪强度表现为,香根草3°香根草25°自然生草3°自然生草25°,土壤抗冲指数表现为,香根草3°香根草25°自然生草3°自然生草25°;4)与自然生草相比,含香根草土体结构稳定,抗剪、抗冲能力强,在3°和25°坡耕地上均表现出一定的固土抗蚀效应。  相似文献   

7.
香根草和马唐的根系特征及对坡地紫色土抗侵蚀性的影响   总被引:1,自引:0,他引:1  
为探讨紫色土区草类根系特征及对土壤抗侵蚀性的影响,本试验选取坡地香根草和马唐为研究对象,分0~10 cm、10~20 cm和20~30 cm土层采集根系和土壤样品,分别采用WinRHIZO(Pro.2004c)根系分析系统、ZJ型应变控制式直剪仪和改进的原状土冲刷水槽测定根系指标、根-土复合体抗剪和抗冲性能,研究了不同土层香根草和马唐的根系特征及与土壤抗侵蚀性之间的关系。结果表明,0~30 cm土层范围内,香根草根系的总体指标和径级指标(根长密度、根表面积密度、根体积密度和根重密度)均优于马唐;较之马唐,香根草更有利于降低土壤容重,改善土壤微团聚体组成状况和提高土壤有机碳含量;上述2种草类根-土复合体的抗冲剪性能均表现为:0~10 cm土层最优,10~20 cm土层次之,20~30 cm土层最差,且各土层均表现为香根草的优于马唐的;相关分析表明,1.0相似文献   

8.
防寒措施对冬季低温下移植香根草的影响研究   总被引:1,自引:2,他引:1  
冬季低温条件下采用常规农艺防寒措施,旨在探索解决低温下种植香根草Vetiveria zizanioides难题的途径.试验结果表明:1)香根草移栽后采用覆膜措施比覆土壅根和对照春季存活率高,而且香根草春季返青、分蘖早,但最终存活率没有显著性差异;2)覆膜措施在各移栽期防寒效果较为稳定,而覆土壅根措施和对照的防寒效果因种植时间的不同而呈现差异;3)农田平地上种植的香根草春季存活率比在公路斜边坡上高,预示着香根草春季存活率高低与土壤水分、肥力等非温度因素有关;4)不同防寒措施对香根草分蘖影响不显著;5)从经济和技术角度来看,覆膜防寒措施是可行的.  相似文献   

9.
综述了香根草在国内外的利用和研究进展,通过总结国内外对香根草在农业、牧草、香精提取、水土保持、城市垃圾治理、饲料、食用菌培育、土木工程防护等方面的应用,表明了香根草综合利用的经济效益和生态效益,并对其目前优化栽培加以论述。  相似文献   

10.
为研究不同种植年限香根草在煤矸石山中的形态觅食行为,以贵州省六盘水大河煤矿2002年、2007年、2009年和2012年种植的香根草为研究对象,分别对不同生长期香根草的生物量、根长、株高、分蘖数、分蘖距离和基茎粗进行测定。结果表明:生物量、分蘖距离和基茎粗在4个生长期均随着种植年限的延长先增加后降低,种植8年(2007年种植)时达到最大。而分蘖数、株高和根长在4个生长期随种植年限的延长呈现持续上升的趋势。香根草的形态可塑性受种植时间的长短影响较大,而不同生育时期对其影响较小。从形态觅食的角度而言,利用香根草对煤矸石山进行生态治理时,其最佳修复年限为8年。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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