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961.
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963.
Economic Botany - Socioeconomic Factors and Cultural Changes Explain the Knowledge and Use of Ouricuri Palm (Syagrus coronata) by the Fulni–ô Indigenous People of Northeast...  相似文献   
964.
ABSTRACT

Population estimates of male Western Capercaillies Tetrao urogallus were carried out during the mating season using two methods: counts of singing males and non-invasive genetic analysis. Estimates of male numbers were 50% lower using the singing counts compared to the estimates obtained through genetic analysis, and underestimates were greatest when the number of Capercaillies was lowest.  相似文献   
965.
Plant and Soil - Southern South American Proteaceae can occupy soils that are rich in total phosphorus (P) but poor in available P (for example volcanic soils) thanks to their cluster roots (CR),...  相似文献   
966.
International Journal of Primatology - Hybridization is relatively well documented among Old World primates, but poorly investigated among New World monkeys. We investigated hybridization between...  相似文献   
967.
Pomacea flagellata is a gastropod conspicuous in freshwater environments, and represents a fishing resource. To assess their abundance, distribution, and secondary production, monthly samplings were carried out in Bacalar Lake from June 2012 to May 2013 at 12 sampling sites. In each site, three random transects were marked parallel to the shore. All snails on transect were collected and shell length and wet weight measured. The highest density occurred in September (1.27 ind.m?2), lowest in October (0.47 ind.m?2). Shell lengths ranged from 2 to 56 mm, with recruitment in January–March. Growth parameters were L 59.50 mm, K 0.65.year?1; the lifetime span was 3 years. Average biomass reached 5.57 wet g.m?2 and secondary production was 6.025 wet g.m?2.year-1; annual renewal rate P/B 1.08. Highest abundance and secondary production was contributed by individuals between 31 and 41 mm in length. A potential biomass of 25.06 tons of snails was estimated in the lake. Snail densities, secondary production, and turnover were very low during the year, indicating that it is not viable to consider a commercial catch without affecting the population. A ban of 10 years is proposed, and aquaculture practices of snails are recommended to recover the resource.  相似文献   
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969.
Biological Trace Element Research - Predator fish can accumulate high levels of mercury, which qualifies them as potential indicators of this toxic metal. The predatory species Brachyplatystoma...  相似文献   
970.
Plant Cell, Tissue and Organ Culture (PCTOC) - Shake-flask in vitro culture of Buddleja cordata cells produces large amounts of biomass and synthetizes verbascoside (VB), linarin and...  相似文献   
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