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91.
Lessons from Białowieża Forest on the history of protection and the world's first reintroduction of a large carnivore
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Tomasz Samojlik Nuria Selva Piotr Daszkiewicz Anastasia Fedotova Adam Wajrak Dries Pieter Jan Kuijper 《Conservation biology》2018,32(4):808-816
Understanding how the relationships between large carnivores and humans have evolved and have been managed through centuries can provide relevant insights for wildlife conservation. The management history of many large carnivores has followed a similar pattern, from game reserved for nobility, to persecuted pests, to conservation targets. We reconstructed the history of brown bear (Ursus arctos) management in Bia?owie?a Forest (Poland and Belarus) based on a detailed survey of historical literature and Russian archives. From the end of the Middle Ages to the end of 18th century, the brown bear was considered “animalia superiora” (i.e., game exclusively reserved for nobility and protected by law). Bears, also a source of public entertainment, were not regarded as a threat. Effective measures to prevent damages to traditional forest beekeeping were already in practice. In the beginning of 19th century, new game‐management approaches allowed most forest officials to hunt bears, which became the primary target of hunters due to their valuable pelt. This, together with an effective anticarnivore policy enhanced by bounties, led to bear extirpation in 1879. Different approaches to scientific game management appeared (planned extermination of predators and hunting levels that would maintain stable populations), as did the first initiatives to protect bears from cruel treatment in captivity. Bear reintroduction in Bia?owie?a Forest began in 1937 and represented the world's first reintroduction of a large carnivore motivated by conservation goals. The outbreak of World War II spoiled what might have been a successful project; reproduction in the wild was documented for 8 years and bear presence for 13. Soft release of cubs born in captivity inside the forest but freely roaming with minimal human contact proved successful. Release of captive human‐habituated bears, feeding of these bears, and a lack of involvement of local communities were weaknesses of the project. Large carnivores are key components of ecosystem‐function restoration, and site‐specific histories provide important lessons in how to preserve them for the future. 相似文献
92.
Maricica Pacurari Diane Schwegler-Berry Sherri Friend Steven S. Leonard Robert R. Mercer Val Vallyathan 《毒物与环境化学》2013,95(5):1045-1072
Single-walled carbon nanotubes (SWCNT) are being developed to be used in many industrial and biomedical applications. However, SWCNT's durability and likely fibrous morphology have raised health concerns. The present investigations were focused on understanding the cellular and molecular mechanisms induced by raw SWCNT (SWCNT) in human bronchial-epithelial cells (BEAS-2B). Asbestos (crocidolite) was used as a positive control. Exposure of BEAS-2B cells to SWCNT induced apoptosis, DNA damage, and oxidative stress. The generation of hydroxyl radical (?OH) and increase of superoxide dismutase (SOD) activity were concentration-dependent. The increase in apoptosis was associated with activation of caspase-3, caspase-7, and poly (ADP-ribose) polymerase-1 (PARP-1). A short recovery period of 6?h of cells from SWCNT exposure resulted in reversal of caspase-3 and caspase-7, and a partial reversal of PARP-1 activation. The activation of PARP-1, caspase-3, and caspase-7 was only partially diminished after a recovery of 6?h from the exposure to crocidolite. Exposure of BEAS-2B cells to SWCNT resulted in the phosphorylation of protein p42/44 (p42/44) and protein p38 (p38). SWCNT did not induce protein serine-threonine kinase (AKT) phosphorylation. For all the above end points, crocidolite induced a greater response compared to SWCNT. SWCNT induced a significant activation of activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB), and the effect was inhibited by mitogen-activated protein kinase (MAPK) inhibitors. SWCNT also induced significant increase in the expression levels of c-Jun, βIGH3, and CD44 genes. The results of this study show that the molecular mechanism for raw SWCNT-mediated toxicity in BEAS-2B cells is through the activation of caspase-3, caspase-7, and PARP-1. Furthermore, the mechanism of AP-1 and NF-κB activation is through MAPK. This bioactivity of raw SWCNT is associated with the generation of oxidative stress and DNA damage. Considering the role of airway epithelium as a critical barrier for normal pulmonary function and focal point for tumor development, this study demonstrates that raw SWCNT activate molecular events which may be linked to adverse biological responses implicated in pulmonary diseases. 相似文献
93.
Application of Amberlite XAD-7 impregnated with morpholine dithiocarbamate (MDTC) for separation and preconcentration of trace amounts of lead, copper, cobalt, iron, nickel, cadmium and zinc and determination by ICP-AES has been described. The optimum experimental parameters, such as pH, sample flow rate, eluent and effect of matrix ions on the preconcentration were investigated. Simultaneous enrichment of the seven metals was accomplished. The t 1/2 values for sorption are 2.9, 3.3, 3.7, 3.6, 2.8, 4.1 and 2.8 respectively for Pb(II), Cu(II), Co(II), Fe(III), Ni(II), Cd(II) and Zn(II). The method was applied for the determination of trace metal ions in seawater and natural water samples. The results have been compared with extraction GFAAS method. 相似文献
94.
针对“京大二试算法”存在的不足——当已知矿井总风量时,“京大二试算法”的迭代格式是错误的,解算出的风量分配不合理,提出了矿井通风网络线性算法的数学模型.该通风网络算法是将支路特性方程变换为线性关系,则风网回路方程被线性化,就可以应用线性逼近法求解.该算法弥补了“京大二试算法”的缺陷,当已知矿井总风量时,解算出的风量值更接近真值,结果更加精确.介绍了线性算法数学模型的迭代格式及迭代精度问题,并编制了该线性算法的Matlab程序,程序简单,节省计算时间,给出了算法原理,并以实例进行计算,得到了令人满意的结果. 相似文献
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针对紫外分光光度法测定污水COD值的误差分析问题,给出了实验的仪器和试剂的配制方法,如测试主要仪器设备和主要试剂的配制,介绍了测定水样的采集地点,介绍了重铬酸钾法的测定原理及步骤,重铬酸钾法的测定原理和重铬酸钾法的测定步骤,紫外分光光度法的测定原理及步骤,如紫外分光光度法的测定原理和紫外分光光度法的测定步骤,并对结果进行了讨论,紫外分光光度法,标准曲线的确定,测定的结果比较和方法的准确度和精密度比较. 相似文献
99.
The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grimes plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old hedge banks. Differences in the floristic composition of the established plant cover between the recent and old hedge banks were determined by multivariate analyses. The species exclusively found in the seed bank and in the herb cover of recent hedge banks were mainly grassland species, whereas the species that only occurred on old hedge banks tended to be woodland species. The floristic composition of the two compartments (established vegetation and seed bank) was very different. A multivariate analysis revealed that the difference between the composition of the seed banks of recent and old hedge banks was less than that between the composition of the established vegetation and seed bank of hedge banks of the same age. Both seed bank and vegetation of recent hedge banks were dominated by ruderal species, whereas old hedge vegetation was dominated by stress-tolerant woodland species, indicating that mechanically constructed hedge banks may impose limitations on colonization by late woodland species. 相似文献
100.
Nives Štambuk-Giljanović 《Environmental monitoring and assessment》2001,71(3):279-296
The article presents the results of chemical andmicrobiological measurements of the water quality in theBuko Blato reservoir, the largest in Europe, in the period 1989 to 1998.The aim was to observe possiblechanges in water quality during the past decade and itsinfluence on the downstream section of the Cetina River andits numerous tributaries and reservoirs, where there are twolarge regional water supply systems. This reservoir wasbuilt in order to exploit the high hydro-electric potentialof small streamflows in the karst fields of south-westernBosnia. It has strongly influenced the hydrologicconditions of the downstream section of the Cetina River.Buko Blato is a relatively shallow reservoir with the meandepth of 5 m. It covers an area of 57 km2. The waterexchange in the reservoir is slow, occurring from one toseveral years. When the water inflow exceeds the hydroelectric plant demands the excess water is delivered by a reversible channel and pre-pumped into the Buko Blato reservoir. The total and carbonate water hardness in thereservoir is lower than in the Cetina River and in typicalkarst streamflows, since the water in this reservoir comesmainly from surface sources including numerous springs withhigh capacity oscillations, torrents and rainfall.Measurements, carried out during the past years, showed asignificant increase in nitrate content as well as in thecoli bacteria and a less significant increase in totalphosphorus content. The water quality was evaluated asmezotrophic according to the total phosphorus content basedon the Carlson index of trophic level, a lower quality thanin the Perua reservoir, upstream on the Cetina River. Thelatter contains a smaller phosphorus content and wasclassed between oligotrophic and mezotrophic. According tothese data, employing the Vollenweider equation, the totalphosphorus content in this water should not exceed the meanof 20 mg m-3 P. The results indicate that the water inthe Buko Blato reservoir did not deteriorate the waterquality on the downstream section of the Cetina River. 相似文献