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1.
青海省都兰县草地生态系统服务功能及其价值评估初探 总被引：1，自引：0，他引：1
对青海省都兰县不同草地类型的生态系统服务价值和类型功能价值进行了尝试性的估算。结果表明,草地系统年平均价值为55.40亿元,各类草地提供的生态服务总价值为:温性荒漠16.50亿元>温性草原13.64亿元>高寒草甸11.60亿元>高寒草原7.61亿元>低地草甸6.05亿元。草地各类功能价值中,提供食物生产的经济价值仅是草地服务价值的一小部分,草地生态系统提供给人类服务最主要的是其潜在的间接生态功能和服务价值。 相似文献
2.
新疆草地生态系统服务功能与价值初步评价 总被引：20，自引：4，他引：16
对新疆草地生态系统的主要功能进行调查,重点估算了新疆草地生态系统不同服务功能和类型的生态价值。计算结果显示,新疆草地生态系统2003年提供的总服务价值为71.32×108美元。从草地各类功能价值看,草地的经济功能价值仅为21.26%,远低于草地的生态价值。从新疆草地类型看,温性荒漠草原、温性荒漠和低平地草甸是新疆草地的主体类型,占58%以上,而其贡献率为43.17%;低平地草甸提供的生态服务价值最高,占30.20%;沼泽和温性草甸草原虽然单位面积服务价值很高,但在草地生态系统中所占的地位很低。这些结论体现了新疆草地生态系统的特殊性及开发和保护的潜力。 相似文献
3.
天祝县草地综合顺序分类及生态系统服务价值评价 总被引：2，自引：0，他引：2
按照草地综合顺序分类方法,利用天祝县及周边地区117个气象台站的资料和DEM分区修正,将天祝县草地分为寒温微干山地草原、寒温微润山地草甸草原、寒温湿润山地草甸、微温微干温带典型草原、微温微润草甸草原和微温湿润森林草原6类.同时考虑土地利用方式和草地退化程度,结合天祝县实际的草地资源分布图和草地的不同等级,利用地理信息系统软件(ArctGIS)工具,对天祝县草地生态系统服务价值进行估算,结果表明:天祝县草地的生态系统服务总价值为5.685亿元/年,其中微温微润草甸草原贡献率最高,达31.52%,寒温微干山地草原草地生态系统服务价值最低,贡献率为8.45%. 相似文献
4.
草原的生态系统服务:Ⅲ.价值和意义 总被引：9，自引：9，他引：0
连续综述了中国草原／草地生态系统服务价值的构成,草地生态系统服务的总价值,各类型草地的生态系统服务的价值。论证了草原／草地为中国提供了最大的生态系统服务价值,草地生态系统服务的生态价值远大于经济价值。论述了草地生态系统服务价值评估具有下列重要意义：1．指明了草地生态系统服务的具体项目及其不可代替性;2．确定了草地生态资本的价值;3．促进了环境成本核算和实现绿色GDP。文章在最后还讨论了草原／草地生态系统服务价值评估中存在的问题。 相似文献
5.
连续综述了中国草原/草地生态系统服务价值的构成,草地生态系统服务的总价值,各类型草地的生态系统服务的价值。论证了草原/草地为中国提供了最大的生态系统服务价值,草地生态系统服务的生态价值远大于经济价值。论述了草地生态系统服务价值评估具有下列重要意义: 1. 指明了草地生态系统服务的具体项目及其不可代替性; 2. 确定了草地生态资本的价值; 3. 促进了环境成本核算和实现绿色GDP。文章在最后还讨论了草原/草地生态系统服务价值评估中存在的问题。 相似文献
6.
青海省海南州天然草地生态系统服务功能价值评估 总被引：1，自引：1，他引：0
利用谢高地等人对草地生态系统服务功能价值估算方法,以草地类估算了青海省海南州各类天然草地生态系统服务功能价值,结果表明：温性草原类为5270．68元／hm^2．a,温性荒漠草原类为2914．90元／hm^2．a,高寒草原类为5023．19．TL／hm^2．a,温性荒漠类为2666．70元L／hm^2．a,低地草句类12527．01元／hm^2．a,高寒草甸类8744．10元／hm^2．a,全州草地生态系统每年的服务功能价值为226．93×10^8元／a。 相似文献
7.
8.
为了科学合理地利用、管理草地,及时准确掌握草原产草量信息和载畜平衡状况,对保障草原的可持续发展具有重要意义。本研究利用2016年5-9月青海的MODIS NDVI、EVI数据和地面调查数据,按草地类型分别建立可食草鲜草产量的估算模型,通过比较基于NDVI和EVI建立的不同产草量估算模型的精度,选出了各类型草地的最优估产模型。在此基础上,计算了不同类型草地的干草产量,并结合畜牧业统计数据估算了青海牧区和半牧区各县(市)的载畜平衡情况。结果表明,1)基于NDVI的可食鲜草产量估算模型精度普遍高于基于EVI的模型,但各类型草地的最优估算模型不同。2)2016年青海省草原干草总产量空间分布差异明显,干草单产在1 200kg·hm-2以上的草地主要分布在东部的禾草草原和高寒草原,干草单产在300kg·hm-2以下的草地主要分布于北部的高寒荒漠以及西部的盐生草甸和高寒草原。对总产草量贡献最大的为高寒草甸,占70.35%。3)2016年青海省29个半牧区和牧区的县(市)中,有21个县(市)为载畜平衡或载畜不足,8个县(市)为超载,并且载畜平衡状况与存栏牲畜密度具有较好的对应关系。 相似文献
9.
基于突变理论构建生态系统服务价值折旧率模型估算草原生态系统服务净价值，运用生态福祉指数评价牧区居民的生态福祉水平，最后通过耦合协调度模型测量二者的耦合协调度水平及其空间差异性。以内蒙古的17个牧业旗县（市）作为研究区，运用2012—2020年的统计数据进行实证研究，研究表明：1）研究区草原生态系统服务净价值增幅达22.9%。典型草原、荒漠草原和草甸草原地区生态环境均得到了不同程度的改善。2）研究区牧区居民生态福祉呈先降后升趋势。典型草原地区牧区居民生态福祉呈先降后升趋势，而荒漠草原地区和草甸草原地区呈波动上升趋势。3）研究区牧区居民生态福祉与草原生态系统服务净价值耦合协调度明显提升。典型草原地区优质协调发展态势逐渐增强；荒漠草原以轻度失调和良好协调为主；草甸草原地区中的2个旗县（市）的耦合协调关系得到了有效改善。 相似文献
10.
山西典型天然草地碳分布特征及碳储量估算 总被引：1，自引：0，他引：1
通过对山西4种主要草地类型暖性草丛草地、暖性灌草丛草地、温性草原、山地草甸草原的地上现存生物量、凋落物、半分解层、根系和土壤有机碳密度的调查和测定,本研究估算山西天然草地生态系统的碳储量,旨在揭示山西不同类型天然草地固碳能力。结果表明:4种类型草地的植被碳密度、土壤有机碳密度、生态系统有机碳密度的大小顺序相同均为:暖性灌草丛草地山地草甸草原暖性草丛草地温性草原;山西草地植被平均碳密度为1759.07g·m~(-2),占整个草地生态系统的21.81%;土壤平均有机碳密度为6307.22g·m~(-2),占整个草地生态系统的78.19%;经估算,山西的草地面积为4.55×10~6 hm~2,草地总碳储量约为364.40Tg。 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.
Tropical Animal Health and Production - 相似文献
14.
Rassnick KM Gieger TL Williams LE Ruslander DM Northrup NC Kristal O Myers NC Moore AS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2001,15(3):196-199
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.
H Hayashi T Yoshimura J Y Chen 《Comparative immunology, microbiology and infectious diseases》1985,8(2):73-87
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.
Davis MS Willard MD Nelson SL Mandsager RE McKiernan BS Mansell JK Lehenbauer TW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(3):311-314
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.
Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects 总被引：1，自引：0，他引：1
Johansson AM Gardner SY Levine JF Papich MG LaFevers DH Fuquay LR Reagan VH Atkins CE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):887-895
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
18.
B. Cinar Kul N. Bilgen J.A. Lenstra O. Korkmaz Agaoglu B. Akyuz O. Ertugrul 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(6):449-453
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
19.
Ling GV Thurmond MC Choi YK Franti CE Ruby AL Johnson DL 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2003,17(6):817-823
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