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81.
广东南岭国家级自然保护区管理有效性与优先性研究 总被引:2,自引:1,他引:1
应用广东省林业自然保护区有效管理评价框架,对广东南岭国家级自然保护区的管理有效性进行评分,计算其管理有效性指数值(ME)和管理优先性指数值(MP),并进行排序.结果表明,广东南岭国家级自然保护区的机构设置、管护设施、管理制度、经费管理、生态旅游、监督与评估的ME值均为1.00,其管理有效性最高;而宣传教育、权属、规划设计、科研监测和管理队伍的MP值均大于1.00,应优先加强管理.为此,该保护区的主要管理对策应包括打造南岭特色生态文化的实体和网络平台、构建利益协商、共享和监管的长效机制以及建设科研监测的新型台站. 相似文献
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Nazlı Savlak Özlem Çağındı Gizem Erk Birsen Öktem Ergün Köse 《Journal Of Aquatic Food Product Technology》2020,29(6):592-602
ABSTRACT Seabream fish bone powder was produced using different chemical methods and tap water. The effect of different chemical procedures (sodium hydroxide (NaOH); NaOH + citric acid; NaOH + sodium hypochlorite (NaOCl); NaOH + ethanol (EtOH); and NaOH + hydrogen chloride (HCl)) and tap water on proximate composition, yield, mineral composition, color, and sensorial odor was investigated. Despite its high bone powder yield (59.39%), tap water treatment was not an efficient method due to low calcium (Ca2+, 232.13 g/kg) and phosphorus (P, 111.63 g/kg) concentration and heavy fish odor. Sensorial odor analysis of seabream fish bone powder showed that tap water received the lowest scores (1.71/5), while chemically treated samples received sensorial odor scores higher than 4.00, with an average of 4.61, indicating that they had a very slight odor. The best fish bone powder yield was obtained using NaOH treatment (21.46%), where Ca2+ (276.73 g/kg) and P (147.23 g/kg) content was also high. The utilization of chemicals in combination with NaOH did not increase the sensorial odor score of seabream fish powders but resulted in a decrease in powder yield. Moreover, the mineral composition of all chemical processing techniques was comparable. Processing by-products of seabream fillet production with 8% NaOH will contribute to daily Ca2+ and P intake of individuals. 相似文献
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We determined the thyroxine (T4) concentration in 63 heifers on 0th (day of insemination), 6th and 21st day after first and in repeat-breeder cows after second and third insemination in relation with the breed, age and weight of animals. The examination was carried out with a feed ration balanced according to the Czechoslovak State Standard CSN 46 7070, with all-the-year-round housing, with keeping the uniform time of insemination (8.00--9.00 a. m.) as well as the time of blood sampling (10.00--12.00 a. m.). The animals were inseminated from August to November. The average T4 concentrations, with a successful insemination, fluctuated on 0th day after first, second and third insemination at levels of 56.15 +/- 13.6; 84.6 +/- 10.66 and 89.75 +/- 13.62 nmol X l-1 of serum. As the results show, the lowest T4 concentrations (P less than 0.001; P less than 0.001) on 0th day were recorded in animals becoming pregnant in first insemination. The comparison with non-pregnant animals did not show any statistically significant difference in T4 concentrations. On 0th day of the second insemination, the T4 concentrations in pregnant animals were higher (P less than 0.01) as compared with non-pregnant. On 6th and 21st day after successful first insemination the T4 content increased significantly (P less than 0.001). After second and third successful insemination we recorded in T4 concentrations a moderate decrease on 6th day (P less than 0.01 for third insemination), with insignificant increase on 21st day.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
86.
N Tekin N Yurdaydin E Klug Y Yavas A Aksu F Gülyüz 《DTW. Deutsche tier?rztliche Wochenschrift》1991,98(9):350-352
Within a German-Turkish university partnership documentation of reproductive data of brood-mares was performed as a part project of the cooperation contract. In the study Arab, Haflinger and cross-breed mares were included. The mares mainly were housed in big studfarms and a smaller part was kept under small private farms. Almost three quarters of both the Arab and Haflinger mares exhibited an estrous length of 1-4 days, whereas the others showed a heat duration of a period of 5-10 days. In the same group of probands a mean length of sexual cycle of 18-24 days could be observed in 38.2% of the Haflinger. The majority of the other mares in both races documented a cycle duration of more than 25 days. The remarkable short duration of heat is discussed as caused by the sharp change from winter to spring environment conditions in that area. An explanation of the marked long mean cycle interval is difficult and might be caused by inadequate documentation of the data. Conception results and foaling data as 83.4% resp. 78.8% in the Arabs and 76.6% resp. 74.8% in the Haflinger mares are within the international standard. Conception rate and foaling data in the cross-breed (72.3% resp. 55.3%) are low compared with data (96.9% 70.8%) of Arab brood-mares kept under stud condition in that area. These data point out the necessity of improving pre- and postconceptional care of the mares under stud conditions as well as in private keeping. 相似文献
87.
Muzaffer Mustafa Harlioğlu 《Aquaculture International》2008,16(4):351-360
This review focuses on the present distribution of populations of the crayfish Astacus leptodactylus that are harvested in Turkey. It also examines the history of this harvest and the impact that crayfish plague has had on them. Crayfish plague, caused by the fungus-like organism, Aphanomyces astaci Schikora, 1906, is a severe parasite of freshwater crayfish and has caused a lot of damage to A. leptodactylus populations in Turkey since 1984. Turkey was the largest provider of A. leptodactylus to Western Europe from 1970 (or possibly earlier) until 1986. For example, the peak production was reached in the early 1980s, with over 5,000 tonnes being exported in 1984. On the other hand, as a result of the crayfish plague the harvest of A. leptodactylus was reduced severely in most populations in Turkey after 1985. The harvest was only 320 tonnes in 1991. After the occurrence of crayfish plague in Turkey, in order to increase crayfish production uncontrolled A. leptodactylus stockings have been carried out in many waterbodies throughout Turkey. These introductions have caused an increase in the number of A. leptodactylus populations, but exploitation of A. leptodactylus is still under the pressure of the plague, although there has been a steady increase in crayfish production in recent years. The harvest increased to 2,317 tonnes in 2004. Fortunately, among those populations affected by crayfish plague, large amounts of A. leptodactylus can still be harvested from three lakes, ?znik (Bursa), E?irdir (Isparta) and Çivril (Denizli). Thus, it seems that A. leptodactylus has a degree of resistance to crayfish plague. It is therefore interesting to investigate the resistance of A. leptodactylus caught from these populations to crayfish plague. 相似文献
88.
Relationship between the serum concentrations of serotonin and lipids and aggression in dogs 总被引:1,自引:0,他引:1
The serum concentrations of serotonin and lipids--triglycerides, total cholesterol, low density lipoprotein, high density lipoprotein and very low density lipoprotein--were determined in 18 normal dogs and 23 dogs diagnosed as aggressive on the basis of interviews with their owners and an assessment of their behaviour with reference to a canine overt aggression chart. The serum serotonin levels in the aggressive dogs were significantly lower than in the normal dogs (P<0.01), but the differences in serum lipids between the two groups were not statistically significant. 相似文献
89.
90.
Owing to unique structure and characteristics of carbon nanotubes, much more are attracted attentions since they were discovered. In recent years, carbon nanotubes have been successfully synthesized by various methods. Especially, highly aligned carbon nanotubes were grown by chemical vapor deposition (CVD) and the oriented growth of carbon nanotubes became realized, resulting in many applications of carbon nanotubes and researches on them. In the work, the methods and mechanisms of orientation growth of carbon nanotubes were reviewed, and it was analyzed and discussed that different methods influenced on the process of growing carbon nanotubes. Simultaneously, it was emphatically analyzed that catalyst particles affected on orientation growth of carbon nanotubes during their growth. 相似文献