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1.
Food waste was collected from local hotels and fish feed pellets were produced for a 6 months long field feeding trial. Three types of fish feed pellets (control diet: Jinfeng® 613 formulated feed, contains mainly fish meal, plant product and fish oil; Diet A: food waste based diet without meat and 53% cereal; Diet B: food waste based diet with 25% meat and 28% cereal) were used in polyculture fish ponds to investigate the growth of fish (grass carp, bighead and mud carp), changes in water quality and plankton density. No significant differences in the levels of nitrogen and phosphorous compounds of water body were observed between 3 fish ponds after the half-year feeding trial, while pond receiving Diet A had the highest density of plankton. The food waste combination of Diet B seems to be a better formulation in terms of the overall performance on fish growth.  相似文献   

2.
In order to explore subsistence patterns in northern Shaanxi Province around 4,000 yr BP,28 human and 24 animal bones from the Shengedaliang site were sampled for stable carbon and nitrogen isotope ratio analysis.The results show that most people primarily subsisted on C_4 resources,e.g.millet and millet-related animal products,despite the fact that there was some intake of C_3 plants by some individuals.Stable nitrogen isotope values indicate that there were differences in meat consumption between individuals at the site.Pigs were mainly foddered with millet and millet byproducts,as well as some cattle,according to their highδ~(13)C values.However,most cattle and the sheep/goats consumed wild C_3 plants at Shengedaliang.Our above findings indicates that subsistence patterns in northern Shaanxi around 4,000 yr BP were characterized by millet farming,while the grassland animal husbandry,e.g.cattle and sheep/goats raising,displayed very little contribution to local economy.The intensive millet farming in northern Shaanxi provided enough food for population growth,ensured the accumulation of wealth,and consequently accelerated social differentiation and complexity.  相似文献   

3.
Despite great achievements in the origins of domestic pigs made by the methods of zooarchaeology and molecular biology, how to scientifically distinguish the domesticated pigs from wild boars during the early stage of pig domestication is still poorly understood. Compared to wild boar’s diets which come from the natural environment, the diets of domestic pigs are more easily influenced by human feeding activities. Therefore, in principle, exploration of the dietary differences among pigs and under-standing the impact on pig diets fed by humans can have great potential to differentiate between wild boars and domesticated pigs. To reveal dietary differences among pigs and distinguish the domesticated pigs from wild boars based on comparison with the diets of humans and other animals, we analyzed the carbon and nitrogen stable isotopes of human bones from Xiaojingshan Site and animal bones from Yuezhuang Site, both of which belong to Houli Culture in Shandong Province and date to about 8500-7500 years ago. The mean δ13C value ((−17.8 ± 0.3)‰) and δ15N value ((9.0±0.6)‰) in human collagen indicate that although millet agriculture began it was not the main subsistence strategy as millets are typical of C4 plants and that humans made a living mainly by gathering, hunting or raising some domesticated animals. The δ13C value (−16.1‰) and δ15N value (6.9‰) in the bovine suggest that C3 plants were dominant in its diet with some C4 plants complemented. The fish has lower δ13C value (−24.9‰) and higher δ15N value (8.8‰) than the bovine, which is the characteristic of the isotopic values from Eurasian freshwater fish. Based on the differences in carbon and nitrogen isotope values, the pigs can be divided into three groups. A group, composed of two pigs, has low δ13C values (−18.1‰, −20.0‰) and low δ15N values (4.7‰, 6.0‰). B group, only one pig, has the highest δ13C value (−10.6‰) and mediate δ15N value (6.4‰). As for the C group, also only one pig, low δ13C value (−19.0‰) and the highest δ15N value (9.1‰) are observed. Previous studies on the stable isotopes from modern or ancient wild boars’ bones have suggested that C3 plants are predominated in their diets and that their δ15N values are close to those in herbivores and far from those in carnivores. Based on the comparison with the isotope values from humans, the wild boars and the domestic pigs from Xipo Site in Henan 6000-5500 years ago and Kangjia Site in Shaanxi 4500-4000 years ago, we conclude that A pig group belongs to wild boars while B and C groups can be attributed to domesticated pigs. Supported by Max-Planck Society and Chinese Academy of Sciences, Knowledge Innovation Program of the Chinese Academy of Sciences (Grant No. KJCX3.SYW.N12), National Natural Science Foundation of China (Grant No. 40702003) and President Funding of Graduate University of Chinese Academy of Sciences  相似文献   

4.
千岛湖水环境质量调查与保护对策   总被引:5,自引:0,他引:5  
1992年7~8月,对大口鲇幼鱼进行了不同饲料喂养和驯化试验,对其摄食、生长进行了研究。试验表明,大口鲇生长迅速,尤其投喂适口的活鱼,其生长速度极快,21天增重2.67~4.60倍,比投喂鱼肉组的体重增长快37.9%~84.3%。具有早晚摄食的习性,平均每克体重日摄食活鱼量为0.1~0.2g,摄食鱼肉量为0.18~0.29g,其饲料系数前者为2.32~3.12,后者为4.15~7.86。试验还表明,大口鲇幼鱼亦摄食人工混合饲料,5cm左右便可用人工饲料进行驯化,但驯化过程要逐渐过渡,驯化期间生长速度受到影响,饲料系数亦较高。  相似文献   

5.
大口鲇幼鱼摄食、生长及驯化的初步研究   总被引:19,自引:4,他引:15  
根据1991年1~12月的调查,陆水水库的浮游植物共8门118属,以绿藻、硅藻、蓝藻门的种类为主,占总属数的86.44%;浮游动物198种,其中原生动物38种、轮虫68种、枝角类61种、桡足类31种。浮游植物年平均数量和生物量分别为3.1449×10~6cell/L和1.937mg/L,数量以蓝藻、隐藻、硅藻最多,占总数量的91.33%,生物量以隐藻、硅藻、绿藻最大,占总生物量的85.03%,浮游植物初级毛产量为3.4gO_2/m~2·d。浮游动物年平均数量和生物量分别为2323.8ind/L和1.4837mg/L,数量以原生动物和轮虫最多,占96.89%,生物量以枝角类和桡足类为主,占79.94%.陆水水库浮游生物种类组成和现存量在不同的水域差异较大,季节变化明显。按水化学分析结果及浮游生物特征判定,陆水水库的营养类型为中营养型。还讨论了环境因子对水库浮游生物的影响。  相似文献   

6.
There is a lack of detailed guidance in the published literature on how to calibrate 14C measurements made on marine or mixed marine/terrestrial (primarily human remains) samples. We describe what we consider to be the best approach towards achieving the most accurate calibrated age ranges, using the most appropriate ΔR and percentage marine diet estimates, and associated, realistic error terms on these values. However, this approach will increase the calibrated age range(s) by fully accounting for the variability in both the model and the material. While the discussion is based on examples from the UK and Iceland, the same fundamental arguments can be applied in any geographic location largely devoid of C4 plants as the high δ13C values from such plants can make identification of marine intake difficult to determine.  相似文献   

7.
The history of cultural exchange in prehistoric Eurasia(CEPE) has been widely investigated. Based on archaeological evidence, this process is thought to date back to at least the early Bronze Age, although details about timings and routes remain unclear. It is likely that CEPE promoted the spread and exchange of crops that originated in different parts of Eurasia; since these remains can be definitely identified and directly dated, they provide ideal research materials to explore the history of CEPE. In this paper, we review the available archaeobotanical evidence and direct radiocarbon dates for crop remains, alongside carbon isotopic data from human bones unearthed from prehistoric sites in Eurasia, in order to investigate the history of the spread of millet crops, and wheat and barley, that were first domesticated in the eastern and western parts of Eurasia during prehistoric times.In combination with other archaeological evidences, we discuss the history of CEPE. Our results suggest that wheat and barley were domesticated in western Asia around 10500 a BP, spread into Europe and western Central Asia before 8000 a BP, and reaching eastern Central Asia and northwestern China between 4500 and 4000 a BP. Data show that both broomcorn and foxtail millet were domesticated in eastern Asia before 7700 a BP, spread into eastern Central Asia between 4500 and 4000 a BP, and into western Asia and Europe prior to 3500 a BP. Wheat, barley, and millet crops were first utilized together in eastern Kazakhstan within Central Asia around 4400 a BP, the region where earliest CEPE is likely to have taken place. These crops were mixedly used mainly in eastern central Asia and northwest China between 4500 and 3500 a BP, and then across the Eurasia before 2200 a BP. The results of this study suggest that transcontinental CEPE might have been initiated during the fifth millennium, before intensifying during the Bronze Age to lay the foundations for the creation of the ancient Silk Road during the Han Dynasty(between 202 BC and 220AD).  相似文献   

8.
Marina P. Vega   《Limnologica》1999,29(2):186
The diet of P. sarsi in different life-stages from copepodid I to adult was investigated. Gut contents of copepodid I to II consisted mainly of algae such as diatoms and dinoflagellates. From copepodid III to adult stages the composition of the diet changed towards the inclusion of nauplii, cladocerans and copepods. The importance of the algae on the diet decreased with the inclusion of the prey items. Copepods were the most important components of the diet from C V to adult. Differences in the capture and ingestion of cladocerans and copepods were found. Diet of P. sarsi can be characterized as diverse consisting of diatoms, phagotrophic algae, protozoans, rotifers and nauplii from C I to C III and consisting mainly of carnivorous items from C IV to adult. The ability to eat a variety of food allows the copepods to modify their diet with varying conditions in the food environment. The effect of these diversity in the diet seems to be advantageous, specially in stressed environments imposed by episodes of drying.  相似文献   

9.
Hominin-animal interactions at Pleistocene archaeological sites have been the main subject of research during human evolution. However, in contrast to that of ungulates, little is known about the evidence of human processing of carnivore species in this time interval of China. In this paper, we present the first case report of an interactive relationship between carnivore species and hunter-gathers in Pleistocene China, based mainly on a detailed taphonomic study of the faunal remains from Shuidonggou Locality 7. It seems highly probable that hominins butchered some individuals of carnivores and roasted bone elements with adhering meat at the site;whereas it’s equally feasible that these animals were exploited by hominins mainly for their pelt or fur. In either way, evidence from the site indicates novel strategies in adaptive behaviors adopted by Late Pleistocene foragers in harsh environments of Northwest China.  相似文献   

10.
Sediment samples from the marine systems along the coast of China, covering Yellow Sea, inner shelf of the East China Sea (ECS) and the South China Sea (SCS), were analyzed for n-alkanes and organic carbon. The concentrations of Σn-C(15-35) were 120-1680ngg(-1) dry weight with an average of 560ngg(-1). Short-chain n-alkanes (C(21)) were mainly derived from terrestrial higher plants. Organic carbon deposited into Yellow Sea and Southeast Hainan within the SCS was mainly of terrestrial (13-110%; mean: 58%) and marine (48-110%; mean: 86%) sources, respectively. On the other hand, organic carbon accumulated in the SCS adjacent to the Pearl River Estuary was derived from both terrestrial and marine sources.  相似文献   

11.
During the climatic fluctuations in the late Late Pleistocene, hominins in China had experienced some significant changes and adaptations in terms of subsistence strategies. Based on the zooarchaeological analyses of the faunal remains from the Shuidougou site of North China and the Ma'anshan site of South China, the present study demonstratively indicates that the broad-spectrum diet and its closely-related resource intensification for hominins were already at their places roughly at 33–35 cal ka BP. Compared to hominins of earlier period, who would have preferentially exploited large and medium-sized ungulates, hunter-gathers at later period had otherwise incorporated more small-sized animals(especially the quick ones, such as birds and hares) into their diet. Meanwhile, hominins of the later time had also greatly accelerated extractions and exploitations of the nutritional yields from the large and medium-sized animals. However, it seems clear from the current study that there was significant difference regarding the potential mechanisms for the broad-spectrum adaptations of hominins in the late Late Pleistocene of China.  相似文献   

12.
鲚(Coilia ectenes taihuensis Yen et Lin)是太湖主要的鱼类之一,其产量随水体富营养化程度的加重呈上升趋势.本研究于2009年4-12月用刺网(a=10 mm)在太湖贡湖湾采集了鲚,分析了其胃含物中食物组成的季节变化以及鲚对食物种类的选择性.结果表明,鲚在各月中主要以浮游动物为食,同时也摄食幼鱼、幼虾和水生昆虫等.鲚的食物组成具有明显季节变化,4月份以桡足类为食,其中桡足幼体、汤匙华哲水蚤(Sinocalanus dorrii Brehm)和剑水蚤(Cyclops spp.)所占的平均个数百分比相当;6、8和10月份主要以枝角类为食,其中6月以裸腹溞(Moina spp.)为主,而8和10月以象鼻溞(Bosmina spp.)为主.食物选择性方面,鲚对大型浮游动物表现出主动选择;当环境中出现溞(Daphnia spp.)和透明薄皮溞(Leptodora kindti Focke)时,鲚对它们表现出很强的选择性摄食,但透明薄皮溞只出现在6月鱼类食物中;个体较小的裸腹溞也是鲚主动选择的重要食物,在整个调查期间鲚对裸腹溞都表现出较高的主动选择性;象鼻溞虽然在各月份食物中的出现率最高,但除10月份鲚对其表现出主动选择外,其它月份表现为主动回避或随机选择.本研究结果有助于我们了解鲚对浮游动物群落影响的季节变化,为制定合理的湖泊与渔业管理方案提供依据.  相似文献   

13.
Alfacs Bay is a N.W. Mediterranean estuary important for mussel (Mytilus galloprovincialis) aquaculture. During studies at the site, fiberglass particles were detected. The presence of fiberglass occurred naturally in the water throughout the study period (November 2006 to July 2007). An investigation was undertaken into its role in the feeding behavior of the local mussels. Fiberglass was present in all types of mussel samples. Rejection, which we would have expected for the whole study period, was only evident during the second season studied. To our knowledge, this is the first report of the ingestion of fiberglass by a marine organism. Our novel finding indicates the need to investigate fiberglass ingestion by marine organisms at different levels of the food web and the possible implications for human health and the health of the organisms themselves. In addition, we propose the use of mussels as sentinel organisms to monitor fiberglass contamination in marine ecosystems.  相似文献   

14.
Enterococci, are used nationwide as a water quality indicator of marine recreational beaches. Prior research has demonstrated that enterococci inputs to the study beach site (located in Miami, FL) are dominated by non-point sources (including humans and animals). We have estimated their respective source functions by developing a counting methodology for individuals to better understand their non-point source load impacts. The method utilizes camera images of the beach taken at regular time intervals to determine the number of people and animal visitors. The developed method translates raw image counts for week days and weekend days into daily and monthly visitation rates. Enterococci source functions were computed from the observed number of unique individuals for average days of each month of the year, and from average load contributions for humans and for animals. Results indicate that dogs represent the larger source of enterococci relative to humans and birds.  相似文献   

15.
Lake Breiter Luzin, located in north-eastern Germany, is known for the rare occurrence of sympatric populations of European cisco, Coregonus albula and C. lucinensis. Moreover, the lake is inhabited by the glacial relict crustacean Mysis relicta, currently found in only three other lakes in Germany. In the present study, the role of M. relicta in the diet of ciscoes was investigated. Between 2001 and 2002 ciscoes, mysids and zooplankton were caught in Lake Breiter Luzin and stomach contents of ciscoes were analysed. There were seasonal changes in the food items in the stomachs, largely reflecting changes in prey availability. The main food items were copepods (45–81%) and mysids (5–26%). Cladocerans had high amounts in the diet only in summer. Seasonal changes in selectivity were also noted for most prey groups. There were also some consistent patterns of prey preference, with an overall preference for mysids. In general, the prey composition in cisco stomachs did not show significant diet changes, but there were some significant differences between day and night feeding in single prey groups, such as cladocerans. Diet composition of ciscoes varied with the different depth strata in which the fish were caught. With increasing depth, the proportion of mysids in the diet significantly increased, whereas that of copepods significantly decreased. Between C. albula and C. lucinensis, no distinct differences in feeding were evident. Mysids provided an additional and important food resource to ciscoes, and were mainly consumed when the availability of other prey organisms decreased, as in autumn and in the deeper strata of the water column. However, mysids preyed on the same food organisms as ciscoes, indicating a strong competition for food between fish and mysids.  相似文献   

16.
赵振伦  杨沁芳 《湖泊科学》1993,5(3):244-252
江苏省瓦沟水库和石山头水库,面积为8.9和17.3hm~2,1984年起分别进行集约化养鱼试验。内容是改革我国传统的水库养鱼方式,设计多种混放密养的养殖模式,增加外源性饵料,改善水库饵料基础,加大鱼种放养规格,缩短饲养周期,实行库湾、池塘等多种培育鱼种形式,实现鱼种自给,开展网箱养鱼,设置网箱簖进行轮捕,饲养家禽家畜,种植青绿饲料,注重综合养鱼。试验结果每公顷鱼产量,瓦沟水库由试验前(1983年)每公顷195kg至1986年达4176kg;石山头水库由1984年的86kg至1989年增加至7822kg,公顷渔业利润为10140元。现这项技术已在江苏省51座小型水库中推广应用。  相似文献   

17.
This study tested the hypothesis that the flood pulse affects the diet composition and the niche breadth of Moenkhausia forestii, a small characid fish inhabiting the littoral zone of lakes. To this end, we compared the diet composition (at the population and individual levels) between hydrological periods (high and low water phases) in a floodplain lake of the Upper Paraná River. PERMANOVA revealed differences in the diet between periods (pseudoF1,38 = 8.5; p < 0.001), with predominant consumption of chironomid larvae and Ephemeroptera (aquatic resources) in the low-water period and an increase in the contribution of terrestrial resources (Hymenoptera, Coleoptera, and Orthoptera) during the high-water period. Based on the PERMDISP results, inter-individual variability in M. forestii diet also differed between periods (F1,38 = 5.80; p = 0.02), with higher values during the high-water period resulting in a dietary niche expansion. During the low-water period, we observed the dominance of chironomid larvae in the diets of most individuals, resulting in lower inter-individual variability and thus narrower niche breadth. The diet of M. forestii was affected by the flood pulse at both the population and individual levels. The most important difference was found in the origin of food items; during the low-water period, the diet consisted mainly of aquatic resources, and during the high-water period, there was a large contribution of terrestrial resources. This variation is related to the increased availability of allochthonous resources in the high period, when terrestrial areas are flooded by the overflow of the river, thereby increasing the input of resources into the aquatic environment. The increased availability of food resources during this period allowed the expansion of the trophic niche of M. forestii, accompanied by the highest richness (19 items) and the highest evenness of food items. Our findings demonstrated that the flood pulse affected the composition of the M. forestii diet at both the population and individual levels. These results support the importance of the flood pulse, which connects aquatic and terrestrial ecosystems, in providing food resources for fish.  相似文献   

18.
古遗址、墓地发掘过程中自然变形的识别研究是反演或充实历史或史前地震变形资料的重要工作。地震部门与文物考古部门合作,对安徽固镇垓下遗址考古现场进行了专题发掘研究,发现了断层和裂缝,初步研究显示为同期2次层位变动事件的遗迹,发生时代约相当于大汶口文化晚期,该工作有助于推动中国东部人类文化层中地震遗迹的识别  相似文献   

19.
The relative importance of dissolved and food pathways and the influence of food type in the bioaccumulation and retention of lead in the shrimp Palaemonetes varians were examined using a radiotracer method. Shrimp were exposed to 210Pb-labelled seawater or fed two types of 210Pb-labelled food, viz. mussels or worms. The amount of radiotracer accumulated by shrimp was examined over a 7-day period, followed by a 1-month and a 7-day depuration period for the dissolved and food source, respectively. Steady state in the uptake was reached after 2 days exposure to dissolved lead, with a resultant estimated concentration factor of 98 ± 3. Transfer factors following ingestion of contaminated mussels and worms were lower than unity for both food types, with lead transfer from worms being significantly higher than that from mussels. Accumulation of dissolved Pb by shrimp was found to occur mainly through adsorption on the exoskeleton with a minor accumulation in the internal tissues probably resulting from the intake of seawater for osmoregulation. In contrast, lead taken up from contaminated food was readily absorbed and bound in the internal tissues of P. varians. Although the transfer of lead to P. varians through the ingestion of contaminated food was low (TF < 1%), it still represented 4 to 8% of the lead content in the prey which is a significant additional contribution of lead to the shrimp body burden. Independent of food type, following ingestion of contaminated food, approximately 23–27% of total lead accumulated in shrimp was located in the edible parts (e.g. muscle). Therefore, the food pathway is suggested to be a significant contributor to the lead transfer to humans through ingestion of contaminated shrimp. After exposure to contaminated food, lead loss kinetics were described by a two-component model, whereas Pb loss following direct uptake from seawater was best described by a three-component model. The additional compartment representing 64% of total Pb retained and characterized by a turnover < 10 min, corresponded to lead weakly adsorbed on the exoskeleton and incorporated in the hepatopancreas. Nevertheless, a significant fraction of lead accumulated from the dissolved (2%) and food (52–57%) pathways remained irreversibly retained in the tissues, suggesting that this organism could also serve as an effective long-term bioindicator of lead contamination in marine waters.  相似文献   

20.
There has been growing speculation to what extent marine animals may gather where physical processes lead to a concentration of food in the vicinity of marine fronts. It appears that at a front off western South America only plankton-eating birds gathered at the front itself, though fish-eating species were most numerous in its general vicinity. Drifting garbage also accumulated at the front, which arrested its spread but may pose a threat to the birds from pollution.  相似文献   

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