24 resultados para wildlife corridors


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A rapid bioassay was established measuring the extracts of wildlife samples which were taken from Ya-Er Lake area, China. In extracts of these samples containing PCDD/Fs and PCBs, bioassay and chemically derived TCDD-equivalents (TEQs) were nearly identical. Our results indicate this bioassay is an excellent complement to chemical residue analysis and a useful tool in understanding the complex interactions of halogenated hydrocarbons. However, it must be mentioned that the proper prior clean-up method is very important for using the bioassay.

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三北"地区和黄土高原是中国沙棘亚种的分布中心,现已有大面积人工沙棘林,但其果小、刺多,产果量低,采果难。为此,作者于1997~2006年承担水利部"948"沙棘引进项目,以解决该地区沙棘优良品种缺乏问题。通过8年试验研究,引进俄罗斯大果无刺沙棘优良品种、类型40余种,分别在"三北"和黄土高原地区的7个主要试验基地进行引种试验,从中初步筛选出效果较好的9个优良品种、类型。它们生长发育良好,抗性较强,具高产、优质特性,并已开始利用引进的俄罗斯沙棘与当地中国沙棘杂交,培育出第一代杂交种。在引种选育和对俄罗斯沙棘生物生态学特性进行试验研究的基础上,对其良种的集约栽培和繁育做了试验和示范推广工作,产生了良好的生态、经济效益。通过本项目实施,为做好沙棘引种选育工作提供了良种,这对大面积建造高产、优质人工沙棘林和沙棘果园,加速黄土高原和"三北"地区的环境治理、发展地方经济具重要意义。

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Thyroid hormones (THs) play an important role in the normal development and physiological functions in fish. Environmental chemicals may adversely affect thyroid function by disturbing gene transcription. Perfluorooctane sulfonate (PFOS), a persistent compound, is widely distributed in the aquatic environment and wildlife. In the present study, we investigated whether PFOS could disrupt the hypothalamic– pituitary–thyroid (HPT) axis. Zebrafish embryos were exposed to various concentrations of PFOS (0, 100, 200 and 400 lg L 1) and gene expression patterns were examined 15 d post-fertilization. The expression of several genes in the HPT system, i.e., corticotropin-releasing factor (CRF), thyroid-stimulating hormone (TSH), sodium/iodide symporter (NIS), thyroglobulin (TG), thyroid peroxidase (TPO), transthyretin (TTR), iodothyronine deiodinases (Dio1 and Dio2) and thyroid receptor (TRa and TRb), was quantitatively measured using real-time PCR. The gene expression levels of CRF and TSH were significantly up-regulated and down-regulated, respectively, upon exposure to 200 and 400 lg L 1 PFOS. A significant increase in NIS and Dio1 gene expression was observed at 200 lg L 1 PFOS exposure, while TG gene expression was down-regulated at 200 and 400 lg L 1 PFOS exposure. TTR gene expression was down-regulated in a concentration-dependent manner. Up-regulation and down-regulation of TRa and TRb gene expression, respectively, was observed upon exposure to PFOS. The whole body thyroxine (T4) content remained unchanged, whereas triiodothyronine (T3) levels were significantly increased, which could directly reflect disrupted thyroid hormone status after PFOS exposure. The overall results indicated that PFOS exposure could alter gene expression in the HPT axis and that mechanisms of disruption of thyroid status by PFOS could occur at several steps in the synthesis, regulation, and action of thyroid hormones.

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理解森林管理对野生动物生境的累积效应,需要对不同森林管理预案作出预测、分析和评价。本文,以小兴安岭友好林业局为研究区,利用空间直观景观模型LANDIS模拟其在6种森林管理预案—无采伐、皆伐、择伐I(禁伐区不采伐,限伐区和商品林区每10年采伐面积分别为5%和10%)、择伐II(限伐区和商品林区10%和15%)、造林I(采伐同择伐I,伐后人工更新)和造林II(采伐同择伐II,伐后人工更新)下200年内的森林景观变化。在查阅文献、野外考察和咨询相关专家的基础上,以GIS为平台,构建有着不同生境需求的3种动物:松鼠(Sciurus vulgaris)、马鹿(Cervus elaphus)和花尾榛鸡(Bonasa bonasia)在景观尺度上的生境适宜度指数(Habitat suitability index, HSI)模型,利用Arc的宏语言AML(Arc Macro Language)将LANDIS的输出结果与3种动物的HSI模型相结合,借助生境单元和类水平(Class level)上的景观指数(结合度指数等)评价动物生境,以反映不同森林管理预案对动物生境的影响。研究结果表明: 1)对于LANDIS的模拟结果而言,不同森林管理预案往往导致不同的森林演替动态:无采伐和2造林方案下,森林逐渐向成、过熟林演替,且造林方案显著增加了营林树种的分布面积;择伐I和择伐II下,由于成、过熟林被采伐,森林向后期演替的速度较为缓慢,而皆伐下,中、幼龄林的比重较大。定性而言,对于偏好早期演替的动物而言,皆伐下的生境适宜性较高;对于偏好中、后期演替森林的动物而言,2种择伐方案下生境适宜性较高;对于偏好后期演替的动物而言,无采伐和2造林方案下生境适宜性较高。 2)对于松鼠,无采伐和2造林预案下的生境单元和适宜生境(HSI≥0.5)结合度指数较高,适宜生境的平均斑块面积较大,表明这3种预案下的生境适宜性较高,而2择伐预案由于移去了大量成、过熟林,导致松鼠生境适宜性的下降,对于皆伐,尽管采伐量比2择伐预案的小,由于其不利于针叶林的天然更新,对松鼠的生境破坏更为严重。 3)对于马鹿,皆伐和2造林预案下的生境单元和结合度指数较高,而无采伐下的生境单元和结合度指数整体上又小于2择伐预案下的,这表明,适当的干扰反而利于提高马鹿的生境适宜性,因为,若没有这些采伐、造林等干扰活动,森林的郁闭度会随着树冠的封闭而逐渐加大,下层的许多不耐荫的树种就会消失或减少,降低马鹿的食物来源。 4)对于花尾榛鸡,若不考虑营林活动对其干扰,2造林预案下的生境单元和结合度指数较高,其次为无采伐预案,而皆伐和2择伐方案下较低,这表明,单纯的采伐的将减小花尾榛鸡的生境适宜性。 生态系统是一复杂的系统,因此,不可能存在适于所有动物的森林管理预案,对于管理预案的选择取决于管理者多方面(经济、生态和社会)的权衡。本文是将LANDIS与HSI相结合模拟评估森林管理预案对动物生境影响的一次尝试,研究结果表明了这一方法的实用性。尽管这一方法存在一定的局限性,但利用这一方法,能够可视化和量化结果,并比较不同森林管理预案,从生物多样性保护出发,为森林管理提供决策支持。最后,需要声明的是,本研究侧重方法的探讨,作为实际应用,还需要大量的野外工作来验证HSI模型。

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中国拥有92466 Km2的各类高原湿地,具有湿地退化、过度放牧等相似特征,保护与利用矛盾突出。高寒湿地保护区尽管在制度上以核心区、缓冲区来约束当地的放牧等外来干扰行为,但在实际管理中却不能起到应有的作用。 本研究以四川若尔盖湿地国家级自然保护区为例,应用3S技术,建立保护区多功能动态分区工作流模型,通过不同植被类型的识别和空间特征分析、不同动物类群在上述植被生境中的时空分布特征分析、保护区主要干扰因素的时空分布特征分析,突出对保护区主要保护对象(湿地生态系统)的保护,对保护区进行管理分区,依据野生动物利用特征和植被生长特征对核心区进行年周期动态利用,缓解保护与发展的矛盾,促进保护区的优化管理。 应用归一化植被指数(NDVI)与植被盖度的相关性,将归一化植被指数(NDVI)转化为植被盖度指数(MDVI),结合保护区牧场划分和时空利用特征专家经验,结果表明,MDVI值在1-139之间主要代表着水体、裸地、沙地等;MDVI140-256为草地和高山灌丛;MDVI210是当地夏牧场和秋冬牧场的划分区间值。 合理的区划需要资金、技术和政策的支持,为保证保护区多核心动态分区的实施,本研究提出了生态工程、牧业发展方式转变、湿地特色产业发展、湿地政策、社区参与和科技支撑等六大保障措施。 In China, 92466 Km2 highland or frigid wetlands are (were) facing major management problems, such as wetland degradation and overgazing. Conflict between conservation and utilization on those wetlands can be found anywhere today. Although many nature reserves have been setup for protection of frigid wetland, and core and buffer zone has been declared to forbid any kinds of disturbance, local farmers still use these areas for grazing. As an example by Sichuan Roige Wetlands National Nature Reserve(SRWNRR), we set up a 3S flow model to analyze the character of year-round distribution patters of vegetation, wildlife, and grazing. Combined and overlapped these characters together, we select multi-core zone and buffer zone, then define a dynamic management period in different zone to optimize protection wetland in the reserve. Normalized Difference Vegetation Index(NDVI)is highly related with coverage of vegetation. When convert NDVI to MDVI (coverage index, 1-256), index 139 and 210 can be as inflexion to distinguish among water/sand/bared land, summer pasture, and autumn / winter pasture. We use these to select different layers and analyze grazing pattern. To be more realistic, we put forward some strategies to support our multi-core and dynamic management of wetland in Roige, including ecological restoration engineering, changing of stock raising industry, changing of wetland policy, community based management and technology renovation supports.

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大熊猫(Ailuropoda melanoleuca)是我国特有的濒危野生动物之一,迁地保护已经成为大熊猫物种保护的一个重要方面。当前大熊猫圈养种群数量增长很快,但是其“多雄配一雌”的交配(配种方式),以及生产过程中记录遗失等原因,造成圈养种群普遍存在亲子关系不清、谱系混乱等问题。为了加强遗传管理,有必要进行亲子关系鉴定、完善谱系;还需要检测种群的基因多样性水平,并在此基础上提出相应的遗传管理建议。 本研究应用9个具有高度多态性的大熊猫微卫星标记,对来自成都大熊猫繁育研究基地2006和2007年度出生的17只大熊猫幼崽及其全部候选父母共37个样品做了基因型分析;然后应用最大似然法,判断幼崽的父-子关系。同时,还对来自卧龙大熊猫保护研究中心的31只大熊猫个体也做了基因分型。将两个种群的数据进行比较:1)等位基因多样性和杂合度水平;2)通过F统计法,分析两个种群的遗传分化水平;3)通过遗传距离法,对所有个体进行聚类分析。 研究结果表明: 1)在母子关系不清的情况下,9个微卫星标记联合的父亲鉴定排除概率E为0.940090;而在母子关系确实的条件下,E= 0.993933。由于本研究中所有后代的母亲都是清楚的,因此这9个微卫星位点能够有效用于圈养大熊猫的亲子鉴定。似然法分析也表明,本研究所获得的亲子鉴定结果置信度在95%以上。 2)2005年种源交换后,成都大熊猫的等位基因多样性和杂合度水平都略高于卧龙种群(但没有达到显著水平),两个种群间的遗传分化水平也有所降低。但是,与卧龙相比,成都种群面临较大的近交压力。 基于以上研究结果,我们建议:进一步加强种源交换和基因交流,把两个种群当作一个遗传单元(MU)来进行管理。 Giant panda (Ailuropoda melanoleuca) is one of the endangerd wildlife endemic to China, and the ex-situ breeding become more and more important for the conservation of this speices. Although the captive population is expanding rapidly, the uncertainty occurs because the paternities of cubs are not clear due to the breeding pattern of “multiple male to single female,”as well as the records lost, resulting in errors in the studbook. For this reason, the paternity of the cubs and the genetic diversity of the captive giant pandas should be tested carefully to get information for the genetic management in the future. 9 polymorphism microsatellite markers were used to do paternity assignment for the 17 cubs born in 2006 and 2007 from Chengdu Research Base for Giant Panda Breeding (CGB) based on the maximum-likelihood methods. A total of 37 individuals were sampled, including all the candidate dams and sires. These samples were also used for comparing with 31 individuals sampling from Wolong China Research and Conservation Center for the Giant Panda (WCG). The comparing indexes were: 1) Allelic diversity and heterozygosity; 2) Genetic differentiation based on F-statistic; 3) Cluster analysis based on genetic distance. The results show that: 1) If the mother is unkown, the combined exclusion probability using these 9 loci is 0.940090. If the mother is known then the exclusion probability is 0.993933. Since the dam-offspring relationship is known in captive populations, the results could resolve unknown paternities in the study. And the confidence level of the results is 95% based on the likelihood methods. 2) The allelic diversity and the heterozygosity of CGB were higher than WCG (n ot significant), and the genetic differentiation was reduced a little since the genetic exchange between two populations in 2005. However, the population of CGB will be threatening by inbreeding seriously than that of WCG. From above, we suggest to reiforce the genetic exchange and geneflow between CGB and WCG, and these two populations should be regarded as one genetic management unit (MU).

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Landscape agriculture is the combination of landscape ecology and agriculture. Its basic idea is from the system theory and landscape ecology. Now landscape agriculture is getting more and more attention because of its multi-functional roles. For example, it can exploit the agricultural ecosystem more rationally, make full use of the self-adjustment function of the natural patches and corridors in the field, as well as the effects from landform types and topological components. It uses regenerative biological energy to a large extent, constitutes beautiful scenic view and protects the diversity of genetics, species, ecosystems and landscapes. Landscape agriculture emphasizes environment improvement, bio-diversity protection and tourism development, thus provides new possibility for the increase of economical benefits and gets the positive feedback loop started. An example from the former Soviet Union is presented as well in this paper

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Herbivory and burrowing activity of mammals may influence the species composition and diversity of plant communities. The effect of corridors and holes systems constructed by root vole (Microtus oeconomus Pallas) on the plant species diversity was studied in the habitat of high - mountain meadow (3250 in a.s.l in Qinghai-Tibet Plateau, China). By using grid method, these disturbances were studied on 16 plots (100 cm x 100 cm) distributed in 4 transects in studied area, in August 2000 and 2001. The disturbance intensity index, D, was calculated as the percent of the ground surface disturbed by voles in the study area. Plant species were identified and counted on the same plots. In total 46 plant species were identified - 39% of this number was considered as sensitive to the vole disturbances as their occurrence and/or abundance decreased along the disturbance intensity. Generally, a significantly negative correlation (r = - 0.911 P < 0.01) between vole aboveground disturbances and plant species diversity (H') was found. The results suggest that root vole ground disturbances, especially in the form of actively utilized holes and corridors have significantly negative influence on plant species diversity in high-mountain grassland habitat.

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1. Plateau zokors, Myospalax fontanierii, are the only subterranean herbivores on the Tibetan plateau of China. Although the population biology of plateau zokors has been studied for many years, the interactions between zokors and plants, especially for the maintenance and structure of ecological communities, have been poorly recognized. In the past, plateau zokors have been traditionally viewed as pests, competitors with cattle, and agents of soil erosion, thus eradication programmes have been carried out by local governments and farmers. Zokors are also widely and heavily exploited for their use in traditional Chinese medicine.2. Like other fossorial animals, such as pocket gophers Geomys spp. and prairie dogs Cynomys spp. in similar ecosystems, zokors may act to increase local environmental heterogeneity at the landscape level, aid in the formation, aeration and mixing of soil, and enhance infiltration of water into the soil thus curtailing erosion. The changes that zokors cause in the physical environment, vegetation and soil clearly affect the herbivore food web. Equally, plateau zokors also provide a significant food source for many avian and mammalian predators on the plateau. Zokor control leading to depletion of prey and secondary poisoning may therefore present problems for populations of numerous other animals.3. We highlight the important role plateau zokors play in the Tibetan plateau ecosystem. Plateau zokors should be managed in concert with other comprehensive rangeland treatments to ensure the ecological equilibrium and preservation of native biodiversity, as well as the long-term sustainable use of pastureland by domestic livestock.