Non-timber forest products and household incomes in Bonga forest area,southwestern Ethiopia     

Ermias Melaku  Zeleke Ewnetu  Demel Teketay 《林业研究》2014,25(1):215-223

We identified the major non-timber forest products （NTFPs）, their contributions to household incomes, and the determinants influenc-ing engagement of households in using NTFPs in the Bonga forest area of Gimbo and Decha Districts of Kaffa Zone, southwest Ethiopia. Six Kebeles （the lowest administrative unit in Ethiopia） were sampled from two Districts and 150 households were randomly sampled using propor-tional-to-size techniques based on the number of farm households in each Kebele. Secondary data were collected from and focus group discussions were conducted with selected individuals. The farmers diversified liveli-hood activities such as crop and livestock production, collection of NTFPs and off-farm activities. NTFPs played a significant role in household incomes. The contribution from the major NTFPs （forest coffee, honey and spices） accounted for 47% of annual household in-come. The role of NTFPs was influenced by a number of factors. Vari-ables including being native to the area （＋）, total land holding （＋）, pos-session of livestock （＋） and access to extension （＋） significantly affected forest coffee production. Age of household head （-）, land holding （＋） and distance of the market from the residence （-） significantly affected honey production. Size of landholding （＋）, distance to market （-） and distance of the forest from the residence （-） were significant variables determining the NTFP incomes derived by the households. Attention is needed in the design of policies and strategies for the well-being of households to the contribution of NTFPs to local incomes and the variables that affect the collection of NTFPs must be considered.  相似文献   

干旱胁迫下Si对甘蔗叶片相对水含量和抗氧化物酶活性的影响     

梁潘霞  ;廖青  ;邢颖  ;江泽普  ;李杨瑞 《广西农业科学》2014,(12):2188-2192

【目的】研究干旱胁迫下不同Si（硅）水平对不同耐旱性甘蔗品种的抗氧化物酶活性的影响,为探索Si提高甘蔗抗旱性的生理基础提供依据。【方法】采用水培法,设置3个施Si浓度（0、0.2、1.7 mmol/L）,经不同PEG-6000胁迫时间（0、18、26、30、40 h）后,测定两个耐旱性甘蔗品种（ROC16和ROC22）甘蔗叶片的相对水含量（RWC）及超氧化物歧化酶（SOD）、过氧化物酶（POD）和过氧化氢酶（CAT）等保护酶活性。【结果】与对照处理（Si浓度0 mmol/L,PEC-6000胁迫时间0 h）相比,随着胁迫时间的延长不同浓度Si处理的叶片RWC持续下降,POD活性先降后升,CAT活性先升后降,SOD活性则表现为先降后升再降的抛物线式变化趋势。ROC22的抗氧化物酶活性均高于ROC16。【结论】施Si能提高甘蔗叶片RWC及SOD、POD和CAT的活性,且高Si浓度（1.7 mmol/L）比低Si浓度（0.2 mmol/L）效果好。  相似文献   

大学生党员在校园文化活动中的引领作用及其实践途径和机制     

刘雪光 《绿色科技》2014,(11):305-307

指出了大学生党员是新时期校园文化活动的主力军,而校园文化活动又是大学生党员发挥引领作用、提高素质及能力的重要载体。从大学生党员发挥引领作用入手,探讨了大学生党员在建设先进校园文化中如何发挥其积极作用,从而建立一套完整的机制使大学生党员充分发挥其在校园先进文化建设中的作用,为建设社会主义和谐社会提供参考。  相似文献   

饲料中添加鸡肠粉对鲤抗氧化及部分免疫酶活力的影响     

彭祖想  严林  卫力博  翟浩杰  高欣  王伟  任同军  韩雨哲 《河北渔业》2022,(1):6-11

为研究饲料中添加鸡肠粉对鲤(Cyprinus carpio)抗氧化能力和部分免疫酶活力的影响,配制了4组等氮等脂饲料和1组鸡肠粉含量为100％ 的饲料,标记为D1、D2、D3、D4、D5.鸡肠粉添加量分别为0％(D1)、5％(D2)、10％(D3)、15％(D4)和100％(D5).选取初始体重约为57 g的鲤150尾...  相似文献   

抗裂与易裂枣内源激素含量和细胞壁代谢相关酶活性比较   总被引：4，自引：0，他引：4  

曹一博  李长江  孙帆  张凌云 《园艺学报》2014,41(1):139-143

 以枣抗裂果品种‘圆铃枣’和易裂果品种‘俊枣’为材料,测定了果实生长发育曲线、果 形指数及种子败育率,并对果皮、果肉、种子中内源激素含量及果皮、果肉中细胞壁代谢相关酶的活性 进行了检测。结果表明,‘俊枣’果形指数和种子败育率均显著高于‘圆铃枣’。果实发育后期‘俊枣’ 果皮中的GA3 含量、果肉中的IAA 含量明显高于‘圆铃枣’,而‘圆铃枣’果肉及种子中的ABA 含量高 于‘俊枣’;‘俊枣’果肉及种子中（GA3 + IAA + ZT）/ABA 的比值在整个果实生长发育期均高于‘圆铃 枣’。果实生长发育后期‘俊枣’果皮中的果胶酶及纤维素酶活性高于‘圆铃枣’,且‘俊枣’果肉中的 POD 及PPO 活性也较高。以上结果显示,枣果实生长发育后期易裂品种‘俊枣’果肉中的IAA 积累较多, 而抗裂品种‘圆铃枣’果肉及种子中ABA 含量显著高于易裂品种;易裂品种‘俊枣’果肉及种子中（GA3 + IAA + ZT）/ABA 的比值较高,果皮中的果胶酶、纤维素酶活性影响裂果的发生,其POD 及PPO 活性相 对较高。  相似文献   

Recording cerebellar neuron activities in swimming goldfish   总被引：1，自引：0，他引：1  

Noritaka Matsumoto  Masayuki Yoshida  Kazumasa Uematsu 《Fisheries Science》2007,73(3):512-521

ABSTRACT:   Neuronal activities were investigated in the cerebellum of immobilized and swimming goldfish Carassius auratus . Extracellularly recorded neural activities of the cerebellum in immobilized goldfish were characterized and classified into five types. Based on the waveforms and recording depths, these five neural activity types were estimated to originate from three identified classes of cerebellar neurons: Purkinje cells, eurydendroid cells, and granule cells. Chronic recording of cerebellar neuron activities in unrestrained goldfish was performed for more than 100 h. During the chronic recordings, a submersible amplifier attached to the goldfish head, and a multielectrode array developed for the present study were used. Neuronal activities in the cerebellum of free-swimming fish could also be classified into five types as in the immobilized condition. Firing patterns of two neurons identified as Purkinje cells and eurydendroid cells were analyzed during turning movements of the goldfish. The firing patterns of these neurons changed in relation to turning movements. Although some improvements are required, the chronic recording method developed in the present study can be applied to further investigations concerning the direct relationship between brain neural activities and certain behavior.  相似文献   

Nitrogenous waste excretion and accumulation of urea and ammonia inChalcalburnus tarichi (Cyprinidae), endemic to the extremely alkaline Lake Van (Eastern Turkey)     

Dra. Eva Danulat  Stephan Kempe 《Fish physiology and biochemistry》1992,9(5-6):377-386

The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I^–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg^–1 fish·h^–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g^–1·ml^–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min^–1·g^–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min^–1·g^–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

The conservation status of Sabellaria alveolata (L.) (Polychaeta: Sabellariidae) reefs in the Bay of Mont‐Saint‐Michel     

N. Desroy  S. F. Dubois  J. Fournier  L. Ricquiers  P. Le Mao  L. Guerin  D. Gerla  M. Rougerie  A. Legendre 《水产资源保护:海洋与淡水生态系统》2011,21(5):462-471

Summertime and early autumn activity of some enzymes in the carbohydrate and fatty acid metabolism of the crucian carp     

Ylva Lind 《Fish physiology and biochemistry》1992,9(5-6):409-415

In June, July, and September the activities of five enzymes involved in the carbohydrate and fatty acid metabolism, namely phosphofructokinase (PFK), lactate dehydrogenase (LDH), citrate synthase (CS), cytochrome oxidase (cyt ox) and 3-hydroxy-acyl-CoA dehydrogenase (HAD), were measured in the heart, liver, red muscle, white muscle, and gill lamellae of crucian carp (Carassius carassius). LDH activity was measured in both reducing (LDHr) and oxidizing (LDHo) directions.The PFK activity in red and white muscle increased significantly between July and September indicating a preparation to winter anoxia by an increased glycylytic capacity in these organs. The HAD activity of the liver had increased significantly (by more than 50%) by September, also a preparation to winter anoxia as HAD is used in the reversed -oxidation (chain elongation of fatty acids). The LDHr and cyt ox activities in the heart and white muscle were highest in July. This shows that both the anaerobic and aerobic capacities are elevated in mid-summer when water temperature is high and oxygen concentration of the water could fluctuate greatly. The LDHo and CS activities in gill lamellae were lowest in July. The results show that the metabolism of crucian carp is under seasonal influence and that a preparation to winter hypoxia/anoxia could be detected in September.  相似文献   

The cytochrome P450 system of Atlantic salmon (Salmo salar): II. Variations in hepatic catalytic activities and isozyme patterns during an annual reproductive cycle     

Håvard E. Larsen  Malin Celander  Anders Goksøyr 《Fish physiology and biochemistry》1992,10(4):291-301

A group of Atlantic salmon (Salmo salar) was followed through their first year of maturation and spawning. At monthly intervals, starting with juvenile fish in December, 5–7 fish of each sex were killed, and liver and plasma were sampled. The last sampling point was of spawning fish in November a year later. Variables in the cytochrome P450 (P450) system were studied in hepatic microsomes, and estradiol 17 was measured in the plasma of females to assess the maturational status. The P450 1A1-mediated 7-ethoxyresorufin O-deethylase (EROD) started at high levels in winter, but decreased to non-detectable activities in pre-spawning females. Decreases, but not to the same extent, were also observed during this period in total cytochrome P450, cytochrome b₅, NADPH-cytochrome P450 reductase, and in the content of two immunochemically determined P450 isozymes. At the same time, LSI levels increased in maturing females (starting in July), and GSI levels increased in both sexes (starting in May). Sex specific differences were observed in pre-spawning fish in September and October, with levels of total P450, b₅, NADPH-cytochrome P450 reductase, EROD and P450 isozymes significantly lower in females. At the same time, plasma estradiol-17 levels reached peak values in females. The results point to the important role of sex steroids such as estradiol-17 as major factors in the regulation of final sexual maturation. However, this study also indicates that there may be estradiol-17 independent events of equal importance in the early stages of gonadal maturation that may involve the P450 system. The changes observed in the P450 system (as a major drug and steroid metabolizing system) of Atlantic salmon during sexual maturation may be of importance both in the endogenous transduction of hormonal signals, and as a pharmacological basis for designing therapeutic treatment of diseases in the aquaculture industry.Parts of this work were presented at the 5th International Symposium on Responses of Marine Organisms to Pollutants, April 1989 in Plymouth, United Kingdom (Larsen and Goks\/oyr 1989).  相似文献