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1.
本文对我国经济动物养殖业具有的高投入高产出,市场行情变化大,风险大,需要较特殊的养殖技术,以及易被炒种形成“养殖热”等特点进行了精辟的论述,并从此出发分析了经济野生动物的养殖必须具备足够的资金,懂法守法,懂得养殖技术,有较好的环境条件,种原优质和掌握市场行情等条件,对于我国经济动物养殖业大起大落以及产品价廉质差滞销的原因进行了深入分析,并就如何健康发展经济动物养殖业提出了针对性措施。  相似文献   

2.
我国畜禽养殖业产排污系数研究进展   总被引:5,自引:0,他引:5  
畜禽养殖业污染物排放量的核算对于环境形势判断、环境规划和环境决策制定具有重要意义,同时也是畜禽污染治理工程设计的重要基础资料。产排污系数为畜禽养殖业污染物排放量的核算提供了较为客观的方法,是环境领域重要的基础数据。笔者总结了我国近年来畜禽业产排污系数的研究状况,对我国畜禽养殖业产排污系数的发展历程、不同地区采用的测算方法和测算结果进行了系统的梳理和对比,总结了畜禽业产排污系数研究一些典型的应用和改进,并对畜禽养殖业产排污系数的研究进行展望。  相似文献   

3.
我国畜禽养殖业存在的环境污染问题及治理对策   总被引:1,自引:0,他引:1  
畜禽养殖业环境污染问题越来越引起了人们的关注.本文概述了我国畜禽养殖业中存在的环境污染问题并从保护生态环境角度出发,提出了利用现代微生物工程应用技术和常规的处理方法相结合的治理措施。  相似文献   

4.
基于全国第一次污染普查数据,结合各类污染物的产排污系数计算了农业污染物(COD、TN和TP)的产生量、排放量和入河量,对比分析了种植业、畜禽养殖业和水产养殖业的污染物排放现状。结果表明,COD、TN和TP排放量分别在种植业、畜禽养殖业及水产养殖业污染物排放总量中所占比例存在明显的差异性,COD和TN排放量占种植业污染物排放总量的比例分别为52%和45%,COD排放量占畜禽养殖业污染物排放总量的比例达91%,COD排放量占水产养殖业污染物排放总量的比例达80%;而不同产业对COD、TN和TP排放量的贡献率也明显不同,水产养殖业和畜禽养殖业对农业COD排放量的贡献率达到80%以上,种植业对农业TN排放量的贡献率接近60%,水产养殖业对农业TP排放量的贡献率接近60%。因此,若要削减有机物,应主要从水产养殖业和畜禽养殖业着手;若要削减氮类污染物,应主要从种植业着手;若要削减磷类污染物,应主要从水产养殖业着手。通过分析研究区农业污染物排放状况,可为农业污染物的削减和控制措施的制定提供一定的参考价值。  相似文献   

5.
我国城市畜禽养殖业的水污染防治   总被引:13,自引:0,他引:13  
近年来我国城市畜禽养殖业发展异常迅速,畜禽粪尿及废水的污染负荷已超过工业废水和生活污水的总和,成为城市新兴大污染产业,本文针对当前城市畜禽养殖业的发展概况,污染状况与危害,提出相应的水污染防治对策与措施(技术的、政策的和管理的)。  相似文献   

6.
牡蛎养殖是传统养殖贝类支柱产业之一,细菌性病害发生严重阻碍了牡蛎养殖业的发展.通过综述近年来有关牡蛎常见致病性细菌及其致病机理的相关研究,提出防治措施,旨在为我国牡蛎养殖过程中细菌性病害的预防和治疗提供借鉴.  相似文献   

7.
农业面源污染控制既要考虑技术对污染物的削减效果,也要兼顾工程建设-运行成本.以我国近20 a来农业(种植业、畜禽养殖业、水产养殖业)面源污染控制具有代表性的73种技术为对象,根据指标(总氮、总磷、氨氮、COD削减率,建设成本,运行成本)完整性等因素初步选择了12种技术,采用层次-灰色关联度法选择兼顾污染物削减率和成本的最适技术.结果表明:种植业污染控制技术中以农田排水植物-微生物复合处理技术为最好,其次是生态拦截沟渠技术;畜禽养殖业面源污染控制技术中以养殖废水土地渗滤处理系统为最好,其次是人工湿地技术;水产养殖业污染控制技术中以组合填料序批式生物膜法为最好,其次是生物-生态复合处理技术.针对太湖地区实际情况,生态拦截沟渠技术更适合该地区农田排水污染控制,土地渗滤处理系统可用于太湖上游地区畜禽养殖业废水处理,组合填料序批式生物膜法可以用于水产养殖排水处理.所提出的层次-灰色关联度法可满足兼顾污染物削减和工程建设-运行成本的面源污染控制技术比选和决策需求.  相似文献   

8.
应加拿大国际开发署的邀请 ,以国家环境保护总局自然司农村环境处处长李远为团长 ,由中国环境科学研究院、国家环境保护总局南京环境科学研究所、国家环境保护总局对外经济合作办公室的有关同志共 4人组成项目考察团 ,于 2 0 0 0年 7月 2 9日至 8月 12日对加拿大畜牧业环境污染管理及污染防治技术进行了考察。1 加拿大畜禽养殖业的环境管理法规及规范加拿大由各省制定畜禽养殖业环境管理的技术规范 ,畜禽养殖场按畜禽养殖业技术规范的要求对养殖场的环境进行管理。各省制定的畜禽养殖业污染防治技术规范在出台初期是志愿性的 ,但随着环境管…  相似文献   

9.
米氏凯伦藻对蒙古裸腹溞的毒性及致毒途径分析   总被引:1,自引:0,他引:1  
米氏凯伦藻(Karenia mikimotoi Hasen)是一种典型的鱼毒性赤潮藻,近年来在我国频繁爆发,给水产养殖业带了严重的经济损失.在实验室条件下,采用混合培养、隔离培养等手段研究了米氏凯伦藻及不同细胞组分对枝角类蒙古裸腹溞(Moina mongolica)摄食与生存的影响,分析了其致毒途径.结果表明,随着混合...  相似文献   

10.
畜禽养殖业主要废弃物处理工艺消除抗生素研究进展   总被引:1,自引:0,他引:1  
随着集约化畜牧养殖业的不断发展,抗生素被广泛用作饲料添加剂以控制畜禽疾病和促进畜禽生长.用于畜禽养殖业中的抗生素绝大部分都不能被动物体所完全吸收,而是以原形或代谢物的形式随动物的粪便排出体外,然后通过各种途径进入到土壤和水体中,给人类健康带来巨大威胁.本文综述了好氧堆肥、厌氧发酵、高级氧化和人工湿地对畜禽粪便和养殖废水中抗生素的去除效果,重点讨论了不同运行参数对处理工艺去除抗生素的影响,最后根据现行研究仍存在的问题提出今后的工作建议,为畜禽养殖业抗生素污染的控制提供参考.  相似文献   

11.
The Partners in Flight North American Landbird Conservation Plan provided estimates of population sizes for 448 landbird species using a multiplicative model. Input parameters in this calculation included the area of state × Bird Conservation Region polygons, area-specific mean Breeding Bird Survey counts circa 1995, and adjustment factors for the distance over which species may presumably be correctly counted, the assumed pairing of singing males with non-singing females, and variability in the propensity of birds to sing over the course of the survey day. I assessed the sensitivity of this population calculation to changes in the input parameters. I assessed both local and global sensitivity of the model to changes in the parameters with Monte Carlo one-at-a-time simulations and the Fourier amplitude sensitivity test (FAST). Monte Carlo simulations were an estimate of local model sensitivity whereas FAST estimated global model sensitivity, accommodating the potential shared variance between model parameters. Monte Carlo simulations suggested population estimates were 39% more sensitive to changes in the detection distance adjustment than to the other parameters; the other parameters were nearly equal in their contribution to model sensitivity. Conversely, FAST analysis determined that each of the input variables aside from the pair adjustment provided roughly equal contributions to variability in population estimates. The most efficient means for improving continental population estimates for birds surveyed by the Breeding Bird Survey will be through increased scrutiny of the species-specific distance detection and time-of-day adjustments and improved understanding in the spatial and temporal variability in the mean Breeding Bird Survey count.  相似文献   

12.
Breeding habitat selection and dispersal are crucial processes that affect many components of fitness. Breeding dispersal entails costs, one of which has been neglected: dispersing animals may miss breeding opportunities because breeding dispersal requires finding a new nesting site and mate, two time- and energy-consuming activities. Dispersers are expected to be prone to non-breeding. We used the kittiwake (Rissa tridactyla) to test whether breeding dispersal influences breeding probability. Breeding probability was associated with dispersal, in that both were negatively influenced by private information (previous individual reproductive success) and public information (average reproductive success of conspecifics) about patch quality. Furthermore, the probability of skipping breeding was 1.7 times higher in birds that settled in a new patch relative to those that remained on the same patch. Finally, non-breeders that resumed breeding were 4.4 times more likely to disperse than birds that bred in successive years. Although private information may influence breeding probability directly, the link between breeding probability and public information may be indirect, through the influence of public information on breeding dispersal, non-breeding thus being a cost of dispersal. These results support the hypothesis that dispersal may result in not being able to breed. More generally, non-breeding (which can be interpreted as an extreme form of breeding failure) may reveal costs of various previous activities. Because monitoring the non-breeding portion of a population is difficult, non-breeders have been neglected in many studies of reproduction trade-offs.  相似文献   

13.
Population trends from the Breeding Bird Survey are widely used to focus conservation efforts on species thought to be in decline and to test preliminary hypotheses regarding the causes of these declines. A number of statistical methods have been used to estimate population trends, but there is no consensus as to which is the most reliable. We quantified differences in trend estimates or different analysis methods applied to the same subset of Breeding Bird Survey data. We estimated trends for 115 species in British Columbia using three analysis methods: U.S. National Biological Service route regression, Canadian Wildlife Service route regression, and nonparametric rank-trends analysis. Overall, the number of species estimated to be declining was similar among the three methods, but the number of statistically significant declines was not similar (15, 8, and 29 respectively). In addition, many differences existed among methods in the trend estimates assigned to individual species. Comparing the two route regression methods, Canadian Wildlife Service estimates had a greater absolute magnitude on average than those of the U.S. National Biological Service method. U.S. National Biological Service estimates were on average more positive than the Canadian Wildlife Service estimates when the respective agency's data selection criteria were applied separately. These results imply that our ability to detect population declines and to prioritize species of conservation concern depend strongly upon the analysis method used. This highlights the need for further research to determine how best to accurately estimate trends from the data. We suggest a method for evaluating the performance of the analysis methods by using simulated Breeding Bird Survey data.  相似文献   

14.
采用比较研究法,分析了甘肃兴隆山麝场圈养马麝(Moschus sifanicus)的非交配季节(8—10月)行为特征的性别间差异,并探讨了行为模式的变化格局.结果表明,由于雌麝在非交配季节正处于哺乳期,育幼投资相对增加,警戒性增强,其静卧、摄食和反刍等行为的终止阈值下降;和雄麝相比,雌麝的站立凝视、静卧、摄食和反刍等行为的发生频次相对较多.育幼直接导致雌麝相互间的冲突行为频次增多,母幼间的行为联系使其亲和行为的表达频次多于雄麝.圈养马麝在非交配季节的月行为节律变化还存在性别差异,在8—9月间,雌麝表达的静卧和反刍行为的频次渐少,而由于雄麝8月后正处于泌香后期(成体)或泌香期(亚成体),因此其运动频次较少,卧息较多,摄食持续时间减少.随繁殖季节的临近,雄麝从8月到10月间的运动、尾阴探究、冲突行为、环境探究等动态行为的表达逐渐增加.图1表2参22  相似文献   

15.
The threatened Marsh Grassbird (Locustella pryeri) first appeared in the salt marsh in east China after the salt marsh was invaded by cordgrass (Spartina alterniflora), a non‐native invasive species. To understand the dependence of non‐native Marsh Grassbird on the non‐native cordgrass, we quantified habitat use, food source, and reproductive success of the Marsh Grassbird at the Chongming Dongtan (CMDT) salt marsh. In the breeding season, we used point counts and radio‐tracking to determine habitat use by Marsh Grassbirds. We analyzed basal food sources of the Marsh Grassbirds by comparing the δ13C isotope signatures of feather and fecal samples of birds with those of local plants. We monitored the nests through the breeding season and determined the breeding success of the Marsh Grassbirds at CMDT. Density of Marsh Grassbirds was higher where cordgrass occurred than in areas of native reed (Phragmites australis) monoculture. The breeding territory of the Marsh Grassbird was composed mainly of cordgrass stands, and nests were built exclusively against cordgrass stems. Cordgrass was the major primary producer at the base of the Marsh Grassbird food chain. Breeding success of the Marsh Grassbird at CMDT was similar to breeding success within its native range. Our results suggest non‐native cordgrass provides essential habitat and food for breeding Marsh Grassbirds at CMDT and that the increase in Marsh Grassbird abundance may reflect the rapid spread of cordgrass in the coastal regions of east China. Our study provides an example of how a primary invader (i.e., cordgrass) can alter an ecosystem and thus facilitate colonization by a second non‐native species. Efectos de Spartina alterniflora Invasora Sobre Locustella pryeri en un Área Donde No Es Nativa  相似文献   

16.
Nestmate recognition in eusocial insects has received a lot of attention in the last decades. Recognition in subsocial species, in contrast, has been ignored almost completely and consequently, and little is known about proximate mechanisms of recognition in subsocial systems. We studied one subsocial species, the biparental brood caring burying beetle Nicrophorus vespilloides, an interesting model organism for studies of recognition because of its ability to discriminate between breeding partners and conspecific competitors. Recognition appears to be based on a chemical cue closely linked to the breeding status of individuals. Breeding and non-breeding beetles consistently differ in their relative proportions of polyunsaturated cuticular hydrocarbons. To investigate the function of these polyenes in the burying beetles’ recognition system, we quantified their concentration on the cuticle during the early state of a breeding attempt and tested the response of breeding beetles in corresponding behavioural experiments. We observed a rapid increase in the proportion of polyunsaturated hydrocarbons of both males and females after they were provided with a carcass suitable for reproduction. Furthermore, we found that the relative amount of polyenes on an individual’s surface was closely correlated with its chance of being accepted as breeding partner. Our results support the idea that polyunsaturated hydrocarbons are involved in breeding partner recognition in N. vespilloides, functioning as a signal that conveys information about the individual’s breeding status. Breeding females have greater amount of polyenes than breeding males, and females ingest more carrion during the first days on the carcass, which supports our hypothesis that precursors for the respective polyenes are derived from ingested carrion.  相似文献   

17.
Common murres (Uria aalge) are highly colonial; pairs often breed at the highest possible densities, in bodily contact with neighbors. At Bluff, a colony in western Alaska, we tested for synchrony in egg laying at various spatial scales and found little evidence for higher synchrony, either within study plots of 15–195 pairs, or within subplots containing several pairs, than among plots in a 5-year study. Egg laying of neighbors generally was more synchronous than expected based on overall frequency distributions in laying dates, however. Breeding success was positively correlated with the number of breeding neighbors and the number of neighbors tending eggs or nestlings at the time of egg laying. Breeding success of pairs with neighbors was positively related to the breeding success of neighbors. Pairs that produced eggs synchronously with at least one neighboring pair had higher success than those that began breeding either before or after their neighbors. Most reproductive failures at Bluff are due to accidental egg loss and predation on eggs by common ravens, Corvus corax, soon after laying. By occupying space where a raven might otherwise land and defending their own eggs, active breeding neighbors locally reduce the probability of egg predation. Active breeding neighbors also are less likely to flush and accidentally dislodge nearby eggs when disturbed than are nonbreeders. Murres breeding synchronously with neighbors have the highest assurance of the presence of active breeding neighbors both at the time of egg laying and throughout their reproductive attempts. Groups of neighboring murres can be considered small “selfish herds,” demonstrating by-product mutualism through their continued presence and defense of their own eggs and nestlings. Despite the advantages of breeding synchronously with neighbors, early breeding may often be favored, however. Received: 22 January 1996/Accepted after revision: 16 June 1996  相似文献   

18.
Link WA  Sauer JR 《Ecology》2007,88(1):49-55
We present a combined analysis of data from two large-scale surveys of bird populations. The North American Breeding Bird Survey is conducted each summer; the Christmas Bird Count is conducted in early winter. The temporal staggering of these surveys allows investigation of seasonal components of population change, which we illustrate with an examination of the effects of severe winters on the Carolina Wren (Thryothorus ludovicianus). Our analysis uses a hierarchical log-linear model with controls for survey-specific sampling covariates. Temporal change in population size is modeled seasonally, with covariates for winter severity. Overall, the winter-spring seasons are associated with 82% of the total population variation for Carolina Wrens, and an additional day of snow cover during winter-spring is associated with an incremental decline of 1.1% of the population.  相似文献   

19.
To investigate if toxic effects by endosulfan, a commonly used insecticide, are dependent on the breeding condition of an organism, both breeding and non-breeding female western mosquitofish, Gambusia affinis, were exposed to 0.1, 0.5, 1 ppb of endosulfan. After a 5-week exposure period, we examined physical factors such as ovary weight and anal fin length in fish of both reproductive conditions and the size of thyroid follicles in non-breeders. Breeding female fish exposed to endosulfan did not show any significant changes in physical factors, but non-breeding females exposed to endosulfan had a significantly greater ratio of anal fin/ body length and larger thyroid follicles than did control females. These results demonstrate that the response to exposure to environmental contaminants may be dependent upon seasonal reproductive condition.  相似文献   

20.
To date, the vast majority of studies in urban areas have been carried out on birds, yet it is not known whether the responses of birds to urbanization are congruent with those of other taxa. In this paper, we compared the responses of breeding birds and carabid beetles to urbanization, specifically asking whether the emerging generalizations of the effects of extreme levels of urbanization on birds (declines in total species richness and the richness of specialist species, increases in total abundance and the abundances of native generalist and introduced species, and community simplification, including increasing similarity) could also be applied to ground beetles. We also directly tested for congruence between birds and ground beetles using correlations between variables describing bird and beetle community structure and correlations between bird and beetle distance matrices describing community dissimilarity between pairs of sampling locations. Breeding bird and carabid beetle community data were collected in Ottawa, Ontario, and Gatineau, Quebec, Canada, in two groups of sites: developed sites representing the predictor variable within-site housing density, and forested sites adjacent to development representing the predictor variable neighboring housing density (each site was 0.25 km2). Breeding birds and carabid beetles do not respond similarly to increasing within-site housing density but do exhibit some similar responses to increasing neighboring housing density. Birds displayed strong declines in diversity, compositional changes, and community simplification in response to increasing within-site housing density. Forest and introduced species of birds and beetles responded similarly to increasing housing density within a site, but responses of overall diversity and open-habitat species richness and patterns of community simplification differed between birds and beetles. Increasing neighboring housing density resulted in increases in the abundances of introduced birds and introduced beetles and similar patterns of community simplification in both taxa. To better understand and mitigate the effects of urbanization on biodiversity, we suggest that, in addition to the responses of birds, future research should focus on the responses of other taxa in the urban matrix.  相似文献   

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