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1.
《畜禽业》2014,(7)
随着畜禽养殖集约化、规模化程度的不断提高,养殖业已成为农牧区经济的支柱产业。但在发展的同时,畜牧业的污染问题非常严峻。如何处理畜禽粪便,控制污染,实现清洁生产的源头治理,从而达到畜禽养殖业粪污处理的要求,变废为宝,实现畜牧业的可持续发展,是科技工作者面临的重大课题。文章介绍了畜禽粪便无害化和资源化处理的几种技术。  相似文献   

2.
本研究从生活源污染、畜禽养殖业污染、化肥及农药施用的面源污染3个方面,分析了崂山水库上游的污染现状,并根据实地调查基础资料,对崂山水库上游污染物入库量和崂山水库的最大纳污量进行了评价,提出了崂山水库上游污染治理的建议对策。可为崂山水库污染物控制提供数据支持,并可为类似地区污染物控制管理提供参考。  相似文献   

3.
姜志文  陈响  汪兆生 《水利渔业》2011,32(4):145-148
柴河水库从流域污染控制、生物修复措施、工程措施和渔业管理等方面进行流域综合治理。通过控制工业、农业和生活污染源头,利用退耕还林、退耕还草和生态果园建设等生物修复技术,堵截污染源、移山造坡、恢复植被、客土固化、生态挡土墙、格栅内种植草坪和改造家属区等工程措施与生物修复技术相结合,并加强渔业管理,探索并实践了水生态环境保护...  相似文献   

4.
随着畜禽养殖业的专业化规模化的不断发展和饲养数量的不断增长,在增加畜禽产品总量、丰富市场供给的同时,也给环境带来了污染。为了畜禽养殖与环境保护的统筹发展,要从源头控制畜禽养殖废弃物总量,并切实做好畜禽养殖废弃物的无害化处理与资源化利用。  相似文献   

5.
水库小流域生态修复对策初步研究   总被引:3,自引:0,他引:3       下载免费PDF全文
通过对试点水库生态现状调查分析、生态修复规划设计及技术方案的实施,对水库小流域水源涵养林、消落区植被、库尾湿地和水库水体生态修复进行了研究。针对小流域存在的林相结构单一、陡坡种果严重、人工林出现衰退、水土流失、面源污染等生态问题,初步实施了退果还林、人工纯林改造、苗圃建设、消落区植被营造、自然湿地恢复、水体污染控制等生态修复措施。  相似文献   

6.
柴河水库从流域污染控制、生物修复措施、工程措施和渔业管理等方面进行流域综合治理。通过控制工业、农业和生活污染源头,利用退耕还林、退耕还草和生态果园建设等生物修复技术,堵截污染源、移山造坡、恢复植被、客土固化、生态挡土墙、格栅内种植草坪和改造家属区等工程措施与生物修复技术相结合,并加强渔业管理,探索并实践了水生态环境保护的系列措施,取得明显效果,水环境状况向好的趋势转变。  相似文献   

7.
水库小流域生态修复对策初步研究   总被引:1,自引:0,他引:1       下载免费PDF全文
通过对试点水库生态现状调查分析、生态修复规划设计及技术方案的实施,对水库小流域水源涌养林、消落区植被、库尾湿地和水库水体生态修复进行了研究.针对小流域存在的林相结构单一、陡坡种果严重、人工林出现衰退、水土流失、面源污染等生态问题,初步实施了退果还林、人工纯林改造、苗圃建设、消落区植被营造、自然湿地恢复、水体污染控制等生态修复措施.  相似文献   

8.
《畜禽业》2016,(12)
正近年来,随着人民生活水平的提高,畜禽养殖业迅猛发展。但畜禽养殖业快速发展带来的废物和污水排放量剧增,已成为农村三大面源污染之一,对农村生态环境造成了严重的破坏。如何整治畜禽养殖污染,促进畜禽养殖业可持续发展已成为全社会关注的问题。1造成畜禽养殖污染的原因1.1治污设施落后由于我国畜禽养殖目前还没有实行规范的、刚性的环境准入制,大部分养殖场都是因陋就简,缺乏统一规划,  相似文献   

9.
市场与信息     
● 中国农业部部署加强淮河流域面源污染防治工作 农村面源污染防治工作是淮河污染治理的重要内容之一,农业部最近发出通知,部署加强淮河流域面源污染防治工作。通知要求: 1.加强领导,大力推动生态农业建设,努力控制农用化学物质污染。农业部将进一步加大沿淮四省生态农业建设工作力度,各有关省在现有工作的基础上,也要加大生态农业的建设力度。建设内容上要突出农药、化肥等农用化学物质的面源污染防治和无公害农产品。 2.采取有效措施,防止规模畜禽养殖场有机污染。沿淮四省各级农业部门要采取措施,对规模畜禽养殖场加强管理…  相似文献   

10.
随着水产养殖规模和产量的不断攀升,水产养殖造成的环境污染问题逐渐引起世界范围内的广泛关注。水产养殖污染是农业面源污染的重要组成部分,通过各种措施进行高效治理和保护,将极大地有利于养殖业的健康和可持续发展。美国在水产养殖面源污染控制方面走在世界前列,具有较多经验可供借鉴。文章对美国水产养殖中应用最佳管理实践(BMP)的概念、内涵和研究应用情况作了简要介绍;对BMP中在工程上和非工程上的2种管理方法进行了深入分析,特别针对工程上和非工程上的关键问题进行了阐述,并提出中国水产养殖生产中应用BMP的重要性。  相似文献   

11.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

12.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

13.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

14.
在基础饲料中分别添加0.1%和1%美人鱼发光杆菌灭活菌、0.1%美人鱼发光杆菌活菌配制成3种免疫实验饲料,以基础饲料为空白对照组饲料,每组设3个平行样。对个体质量为(4.83±0.36)g的凡纳滨对虾进行为期20 d的饲养实验,分别在0、5、10、15和20d进行取样,以血清中的酚氧化酶(PO)、酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、超氧化物歧化酶(SOD)和溶菌酶(UL)活性为免疫指标,探讨了美人鱼发光杆菌作为免疫制剂对凡纳滨对虾非特异性免疫效应的影响;在投喂免疫饲料后的第22天,按0.004 2 kg/kg体重的剂量,直接投喂对虾白斑综合征病毒(WSSV)病料,并记录累积死亡率。结果表明,美人鱼发光杆菌免疫实验组对凡纳滨对虾血清中PO、ACP、AKP、UL和SOD活性影响明显高于对照组,并且在饲料中添加美人鱼发光杆菌后,明显提高了对虾抵御WSSV感染的能力。其中0.1%美人鱼发光杆菌活菌实验组的抗病毒感染能力最强,WSSV感染14d内累计死亡率为63.3%±5.8%;而对照组为96.7%±3.3%。研究表明,美人鱼发光杆菌添加在对虾饲料中能提高凡纳滨对虾非特异性免疫水平,增强抵抗疾病的能力,将其作为对虾免疫增强剂具有良好的应用前景。  相似文献   

15.
This study was carried out to investigate the effects of replacing fish meal with dietary Spirulina as a feed supplement on the growth performance and coloration of blue dolphin cichlids (Cyrtocara moorii). Five isonitrogenous (47% crude protein) and isocaloric (17.36 kJ/g digestible energy) diets were for formulated to replace FM with 0, 5, 10, 15 and 20% Spirulina (designated as Control, SP5, SP10, SP15 and SP20 respectively) and fed to the fish (initial body weight, 3.15 ± 0.01 g). Fish were randomly distributed into fifteen 120 L aquariums (26.5 ± 1.00°C), 15 fish per aquarium. The diets were tested in triplicate for 12 weeks. Experimental groups were fed twice daily (09:00 and 17:00) by hand to satiation. At the end of the feeding trial, significantly (p < 0.05) higher weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER) and lower feed conversion ratio (FCR) were observed in fish fed the SP10 diet when compared to the SP20 diet. There was no significant difference in these parameters between the other groups. The skin coloration of blue dolphin cichlid fed a diet containing Spirulina meal was enhanced. The best coloration was observed in the SP15 group. These impressions were objectively validated by chemical determinations of carotenoids extracted from fish skins and passed statistical tests of significance. The study findings show that Spirulina meal does not diminish growth rates except at very high levels.  相似文献   

16.
Two experiments were conducted to quantify the dietary thiamin (experiment I) and pyridoxine (experiment II) requirements of fingerling Cirrhinus mrigala for 16 weeks. In experiment I, dietary thiamin requirement was determined by feeding seven casein–gelatin‐based diets (400 g kg?1 CP; 18.69 kJ g?1 GE) with graded levels of thiamin (0, 0.5, 1, 2, 4, 8 and 16 mg kg?1 diet) to triplicate groups of fish (6.15 ± 0.37 cm; 1.89 ± 0.12 g). Fish fed diet with 2 mg kg?1 thiamin had highest specific growth rate (SGR), protein retention (PR), RNA/DNA ratio, haemoglobin (Hb), haematocrit (Hct), RBCs and best feed conversion ratio (FCR). However, highest liver thiamin concentration was recorded in fish fed 4 mg thiamin kg?1 diet. Broken‐line analysis of SGR, PR and liver thiamin concentrations exhibited the thiamin requirement in the range of 1.79–3.34 mg kg?1 diet (0.096–0.179 μg thiamin kJ?1 gross energy). In experiment II, six casein–gelatin‐based diets (400 g kg?1 CP; 18.69 kJ g?1 GE) containing graded levels of pyridoxine (0, 2, 4, 6, 8 and 10 mg kg?1 diet) were fed to triplicate groups of fish (6.35 ± 0.37 cm; 1.97 ± 0.12 g). Fish fed diet containing 6 mg kg?1 pyridoxine showed best SGR, FCR, PR, RNA/DNA ratio, Hb, Hct and RBCs, whereas maximum liver pyridoxine concentration was recorded in fish fed 8 mg kg?1 dietary pyridoxine. Broken‐line analysis of SGR, PR and liver pyridoxine concentrations reflected the pyridoxine requirement from 5.63 to 8.61 mg kg?1 diet. Data generated during this study would be useful in formulating thiamin‐ and pyridoxine‐balanced feeds for the intensive culture of this fish.  相似文献   

17.
Marine fish farming in Egypt began in 1976 with the culture of gilthead sea bream, (Sparus aurata) as this fish was notably adaptable to brackish and marine pond conditions. Today, marine fish and shrimp farms amount to about 19,000 ha, out of which 42% is already in production while the rest, i.e., 58% is still under construction. In 1997, cultured gilthead sea bream production of 2,250 tons made up 3% of the 75,000 tons total aquaculture catch. In polyculture, usually with the grey mullet and sea bass, gilthead sea bream contributed 440 kg ha–1 to the total yield of 1,700 kg ha–1 (26%) over a period of 16 months. For the same period, the yield of monoculture ponds averaged 100 kg ha–1, while in marine cages, yields ranged from 4–10 kg m3. In 1996–1997, fry of 0.25–1 g and fingerlings 1–10 g with a total of 3 million, were collected from the wild and 1 million fry were produced in the three marine hatcheries out of the four existing ones. The development of sea bream culture in Egypt is now severely inhibited by the shortage of seeds and adequate feeds. Exports of both sea bream and sea bass, during 1994–1996 averaged 1,300 tons per year.  相似文献   

18.
The cockle Cerastoderma edule fishery has traditionally been the most important shellfish species in terms of biomass in Galicia (NW Spain). In the course of a survey of the histopathological conditions affecting this species in the Ria of Arousa, a haplosporidan parasite that had not been observed in Galicia was detected in one of the most productive cockle beds of Galicia. Uni‐ and binucleate cells and multinucleate plasmodia were observed in the connective tissue mainly in the digestive area, gills and gonad. The parasite showed low prevalence, and it was not associated with abnormal cockle mortality. Molecular identification showed that this parasite was closely related to the haplosporidan Minchinia mercenariae that had been reported infecting hard clams Mercenaria mercenaria from the Atlantic coast of the United States. The molecular characterization of its SSU rDNA region allowed obtaining a fragment of 1,796 bp showing 98% homology with M. mercenariae parasite. Phylogenetic analysis supported this identification as this parasite was clustered in the same clade as M. mercenariae from the United States and other M. mercenariae‐like sequences from the UK, with bootstrap value of 99%. The occurrence of M. mercenariae‐like parasites infecting molluscs outside the United States is confirmed.  相似文献   

19.
20.
Plasma estradiol-17 (E2), testosterone (T), 17,20-dihydroxy-4-pregnen-3-one (DHP) and 17,20,21-tri-hydroxy-4-pregnen-3-one (20-S) levels were measured by radioimmunoassay (RIA) in white perch (Morone americana) and white bass (M. chrysops) that were induced to undergo final oocyte maturation (FOM) with human chorionic gonadotropin (hCG). Plasma DHP levels increased in females of both species in association with oocyte germinal vesicle migration (GVM) and germinal vesicle breakdown (GVBD) and decreased thereafter. Plasma 20-S levels also increased with oocyte GVM in white bass, but were several-fold lower than DHP levels. Circulating E2 and T levels were greatest during GVM and GVBD in both species and decreased to low levels during oocyte hydration and ovulation. Follicles from white perch and white bass which received a priming injection of hCG in vivo, produced both DHP and 20-S in vitro after exposure to hCG and their oocytes underwent GVBD. Ovarian incubates from unprimed fish of either species produced only E2 and T and their oocytes did not complete GVBD. Oocytes from unprimed bass, but not perch, matured when follicles were exposed to hCG in vitro. Both trilostane and cycloheximide blocked in vitro production of DHP and 20-S and oocyte GVBD by white perch follices. DHP and 20-S were equipotent inducers of FOM in the GVBD bioassay. None of several other structurally-related steroids tested were effective within a physiological range of concentrations. These results indicate a role for DHP and 20-S in the control of FOM in white perch and white bass.  相似文献   

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