scholarly journals A successful case of biological invasion: the fish Cichla piquiti, an Amazonian species introduced into the Pantanal, Brazil

2008 ◽  
Vol 68 (4) ◽  
pp. 799-805 ◽  
Author(s):  
EK. Resende ◽  
DKS. Marques ◽  
LKSG. Ferreira

The "tucunaré", Cichla piquiti, an exotic Amazonian fish has become established along the left bank of the Paraguay River in the Pantanal. It was introduced by escaping from culture ponds in the Upper Piquiri River and spread downstream, along the lateral flooded areas of that river, continuing through the clear waters of the left bank of the Paraguay River and reaching south as far as the Paraguai Mirim and Negrinho rivers. Adult spawners have been found in the region, meaning that it is a self-sustained population. Reproduction occurs in the period of low waters. They were found feeding on fishes of lentic environments belonging to the families Characidae, Cichlidae and Loricariidae. Until the end of 2004, its distribution was restricted to the left bank of the Paraguay River, but in March 2005, some specimens were found on the right bank, raising a question for the future: what will be the distribution area of the tucunaré in the Pantanal? Information about its dispersion is increasing: it is known to be in the Tuiuiú Lake, Pantanal National Park and in the Bolivian Pantanal, all of them on the right bank of the Paraguay River. The hypothesis that the "tucunaré" could not cross turbid waters, such as in the Paraguay River, was refuted by these recent findings. Possibly, the tucunaré's capacity to lay more than one batch of eggs in a reproductive period, as well as its care of eggs and young, lead them to establish themselves successfully in new environments, as has been observed in the Pantanal and other localities.

2007 ◽  
Vol 67 (1) ◽  
pp. 53-63 ◽  
Author(s):  
Y. Zalocar de Domitrovic ◽  
ASG. Poi de Neiff ◽  
SL. Casco

Patterns in the temporal composition, abundance and diversity of the phytoplankton community of the Paraná river prior to and after the initial filling phase of the Yacyretá reservoir are analyzed. The study site is located 220 km downstream from the Yacyretá reservoir and 30 km downstream from the confluence with the Paraguay river. Because both rivers remain separate and unmixed at the study site, we compared the possible effects of the impoundment on both river banks (left and right banks) in hydrological periods with similar duration and magnitude of the low and high water phases. Physical and chemical conditions measured on the right bank (water from the Paraguay river) were similar at both periods (pre and post-impoundment) whereas conductivity, pH and orthophosphate concentration increased on the left bank (water from the High Paraná river and Yacyretá reservoir) after the impoundment. Changes in phytoplankton density and diversity were observed only in samples collected from water flowing from the reservoir (left bank). The density of Chlorophyceae (Chloromonas acidophila, Chlamydomonas leptobasis, Choricystis minor, Chlorella vulgaris, Scenedesmus ecornis, Monoraphidium minutum, M. contortum and M. pusillum) and Cryptophyceae (Rhodomonas minuta, Cryptomonas marssonii and C. ovata) increased while Cyanophyceae (Cylindrospermopsis raciborskii, Raphidiopsis mediterranea and Planktolyngbya subtilis) and Bacillariophyceae (Aulacoseira granulata and its bioforms) decreased compared to previous studies conducted on the left bank of the Paraná river. Phytoplankton collected from the right bank of the river did not differ in pre and post- impoundment samples because they originate from the Paraguay river, which remains relatively unaffected by human activities.


Author(s):  
WILLIAM GARDENER

Prince Henri d'Orleans, precluded by French law from serving his country in the profession of arms, had his attention turned early towards exploration. In 1889, accompanied by the experienced traveller Gabriel Bonvalet, he set out from Paris to reach Indo-China overland by way of Central Asia, Tibet and western and south western China. The journey made contributions in the problems of the whereabouts of Lap Nor and the configuration of the then unexplored northern plateau of Tibet; and in botany it produced some species new to science. The party reached Indo-China in 1890. In 1895, having organised an expedition better equipped for topographical survey and for investigations in the fields of natural history and ethnography, Prince Henri set out from Hanoi with the intention of exploring the Mekong through the Chinese province of Yunnan. After proceeding up the left bank of the Salween for a brief part of its course and then alternating between the right and left banks of the Mekong as far up as Tzeku, the party found it advisable to enter Tibet in a north westerly direction through the province of Chamdo and instead crossed the south eastern extremity of the country, the Zayul, by a difficult track which led them to the country of the Hkamti Shans in present day Upper Burma, and thence to India completing a journey of 2000 miles, "1500 of which had been previously untrodden" (Prince Henri). West of the Mekong, the journey established that the Salween, which some geographers had claimed took its rise in or near north western Yunnan, in fact rose well north in Tibet, and that, contrary to previous opinions, the principal headwater of the Irrawaddy rose no further north than latitude 28°30'. Botanical collections were confined to Yunnan, where the tracks permitted mule transport, and they produced a number of species new to science and extended the range of distribution of species already known.


2019 ◽  
Vol 70 (11) ◽  
pp. 3903-3907
Author(s):  
Galina Marusic ◽  
Valeriu Panaitescu

The paper deals with the issues related to the pollution of aquatic ecosystems. The influence of turbulence on the transport and dispersion of pollutants in the mentioned systems, as well as the calculation of the turbulent diffusion coefficients are studied. A case study on the determination of turbulent diffusion coefficients for some sectors of the Prut River is presented. A new method is proposed for the determination of the turbulent diffusion coefficients in the pollutant transport equation for specific sectors of a river, according to the associated number of P�clet, calculated for each specific area: the left bank, the right bank and the middle of the river.


Oryx ◽  
1982 ◽  
Vol 16 (5) ◽  
pp. 437-444 ◽  
Author(s):  
Stephen Makacha ◽  
Michael J. Msingwa ◽  
George W. Frame

The Serengeti National Park in Tanzania is famous for its huge herds of migrating wildebeest, zebras and other ungulates. But these herds spend much of the year in neighbouring reserves where their survival depends on preserving the right conditions. The authors made a study of two of these reserves with disturbing results. The Maswa Game Reserve they found was seriously threatened by invading (illegal) settlement with a fast-growing population cultivating land and felling trees; in the Ngorongoro Conservation Area they report that the Maasai have taken to poaching, both for subsistence meat and for trophies to sell – skins, ivory and rhino horn. In both places the guards are so poorly equipped they can do little to stop poaching.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Martin Rundkvist

Abstract Gold snake-head rings are a famous and much studied artefact group of the Late Roman Period in Scandinavia. But before and during their heyday, women in the same areas were occasionally buried with shield-head and snake-head rings made of silver or bronze. This paper surveys the material and traces the origin of these designs from the Wielbark Culture in coastal Poland about AD 100. The early shield-head rings probably arrived across the Baltic with the women who wore them. After the AD 210s, non-gold rings are a feature of the gold snake-head rings’ core production and distribution area on the Baltic Islands and south-east mainland Sweden. The women who wore them were not tribal royalty, but enjoyed comfortable economic means and had the right to display this top-level symbol in more affordable materials.


Koedoe ◽  
2014 ◽  
Vol 56 (2) ◽  
Author(s):  
Francesca Cini ◽  
Melville Saayman

Age (and its changing structure amongst the wider population) is one of the most relevant aspects required to better understand and forecast the needs, interests and associated consumption behaviours of tourists. This research used age to investigate the expenditure patterns amongst a sample of visitors to the Table Mountain National Park (TMNP), South Africa. In March 2010, visitors to the TMNP were found to differ significantly from those at other parks, as they were younger and most of them were foreigners. This study found that younger visitors (18–29 years) were higher spenders when compared to those aged 30–49 years. As parks are generally visited by older people, this study showed the economic importance of the younger market. The research also made clear implications and recommendations for park management as to how to address these findings. Conservation implications: Conservation is dependent on funding. One of the main sources of income is tourism and tourism related activities. This research can assist marketers and managers to target the right markets in order to be more sustainable. This research also shows the importance of environmental education at an early age in order to grow awareness and to target the right markets.


Author(s):  
V. P. Tkach ◽  
O. V. Kobets ◽  
M. G. Rumiantsev

The forest site capacity using was quantitatively assessed for the stands of the main forest-forming species of Ukraine, Scots pine and common oak, taking into account natural zones and forest types. The tables of productivity of modal and highly productive pine and oak stands have been developed. It has been found that the stands use an average of 50–75 % of the forest site capacity of lands. The average weighted value of the capacity used by pine forests was 68–76 % in the Polissya zone, 70–78 % and 68–73 % in the Right-bank and Left-bank Forest-Steppe zones respectively, and 54–78 % in the Steppe zone. For oak stands, the value was 71–75 % and 63–71 % for the Right-bank and Left-bank Forest-Steppe zones respectively and 65–75 % for the Steppe zone. The basis for increasing the productivity of forests was confirmed to be the differentiation of forest management systems and individual forestry activities on a zonal and typological basis.


Author(s):  
Runumi Das ◽  
Niranjan Das

This paper highlights the implementation of Forest Rights Act to conserving protected areas in the country; Forest Rights Act (2006) has been passed by the parliament of India with dual aims of protecting the right of forest dwellers and at the same time this Act tries to acquire the involvement of forest dwellers to protect forest/protected areas. The main objective of the paper is to determine the factors which influence motivation to spend efforts in terms of work hour for biodiversity conservation in Nameri National Park. A total of 78 numbers of households were interviewed from two forest villages (i.e. Torajan and Dharikati) and two encroached villages (i.e. Rihajuli and Chopaloga) located in the south buffer of Nameri National Park in Assam during March and June of 2021. Respondents in forests village are more willing to spend effort than that of encroacher’s village to conservation. Sex, age, literacy of the respondents and size of land holdings were found to be significantly related to spending time for biodiversity conservation programme. In this paper attempt has been made to emphasize the nature of motivation of the communities towards biodiversity conservation issues.


2021 ◽  
Vol 40 (3) ◽  
pp. 155-168
Author(s):  
D. G. Diachenko

The paper is devoted to the Raiky culture in the Middle Dnieper. It reveals major issues of the phenomenon of Raiky culture and their possible solutions considering the achievements of Ukrainian archeologists in this field. The genesis, chronology and features of the development of material culture of the Raiky sites in the 8th—9th centuries of the right-bank of the Dnieper are analyzed. In general the existence of the Raiky culture in the Middle Dnieper region can be described as follows. It was formed in first half of the 8th century in the Tiasmyn basin. The first wheel-made pottery has begun to manufacture quite early, from the mid-8th century (probably at the beginning of the third quarter). At the first stage, the early vessels have imitated the hand-made Raiky forms as well as the Saltovo-Mayaki imported vessels. Significant development of the material culture occurs during the second half of the 8th century. At the same time, the movement of the people of Raiky culture and the population of the sites of Sаkhnivka type has begun in the northern direction which was marked by the appearance of the Kaniv settlement, Monastyrok, and possibly Buchak. This stage is characterized by the syncretism both in the ceramic complex and in the features of design of the heating structures. Numerous influences of the people of Volyntsevo culture (and through them – of Saltovo-Mayaki one) are recorded in the Raiky culture. It is observed not only in direct imports but also in the efforts of the Raiky population to imitate the pottery of Volyntsevo and Saltovo-Mayaki cultures, however, based on their own technological capabilities. The nature of the relationship between the bearers of these cultures is still interesting. The population of Raiky accepts the imported items of Saltovo-Mayaki and Volyntsevo cultures, tries to imitate high-quality pottery of them, and even one can see the peaceful coexistence of two cultures in one settlement — Monastyrok, Buchak, Stovpyagy. However, the reverse pulses are absent. There are no tendencies to assimilate each other. Although, given the number and size of the sites, the numerical advantage of the Volyntsevo population in the region seems obvious. There is currently no answer to this question. The first third of the 9th century became the watershed. The destruction of the Bytytsia hill-fort and the charred ruins to which most of the settlements of the Volyntsevo culture has turned, is explained in the literature by the early penetration of Scandinavians into the region or as result of the resettlement of Magyars to the Northern Pontic region. In any case, this led to a change in the ethnic and cultural situation in the Dnieper basin. According to some researchers, the surviving part of the population of Volyntsevo culture migrated to the Oka and Don interfluve. For some time, but not for long, the settlements of Raiky culture remained abandoned. Apparently, after the stabilization of situation, the residents have returned which is reflected by the reconstruction of the Kaniv settlement and Monastyrok; in addition, on the latter the fortifications have been erected. The final stage of the existence of culture is characterized by contacts with the area of the left bank of Dnieper, the influx of the items of the «Danube circle», as well as the rapid development of the forms of early wheel-made pottery. The general profiling of vessels and design of the rim became more complicated, the rich linear-wavy ornament which covers practically all surface of the item became characteristic. This suggests the use of a quick hand wheel which has improved the symmetry of the vessels, as well as permitted to create the larger specimens. The evolution of the early wheel-made ceramic complex took place only by a variety of forms, however, technological indicators (dough composition, firing, density and thickness of vessel walls) indicate the actual invariability and sustainability of the manufacture tradition. The discontinuance of the functioning of the latest Raiky sites (Monastyrok and Kaniv settlements) can be attributed as the consequences of the first stages of consolidation of the Rus people in the Middle Dnieper dating to the late 9th — the turn of the 9th—10th centuries.


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