Distribution and environmental preferences of diatoms along the Negro River, Patagonia, Argentina

Limnetica ◽  
2021 ◽  
Vol 40 (2) ◽  
pp. 247-265
Author(s):  
Camilo Vélez-Agudelo ◽  
Marcela A. Espinosa
Keyword(s):  
Environmental Preferences ◽  
Negro River

scholarly journals Ichthyological ethnoknowledge of the “piabeiros” from the Amazon region, Brazil

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Daniel da Silva Ladislau ◽  
Maiko Willas Soares Ribeiro ◽  
Philip Dalbert da Silva Castro ◽  
Jackson Pantoja-Lima ◽  
Paulo Henrique Rocha Aride ◽  
...  
Keyword(s):  
Fish Species ◽  
Local Ecological Knowledge ◽  
Middle Part ◽  
Ornamental Fish ◽  
Ecological Knowledge ◽  
Structured Interviews ◽  
Economic Activities ◽  
Negro River ◽  
Artisanal Fishers ◽  
Ecological Aspects

Abstract Background The capture of ornamental fish is one of the main economic activities of riverine families in the Amazon. However, studies regarding the local ecological knowledge of workers in this activity are still incipient. In view of this, we have studied and explored the local ecological knowledge of artisanal fishers who specialize in the capture of fish for the aquarium trade in the middle part of the Negro River basin and investigated issues related to the ecological aspects of the fish species that are targeted by this trade in the region. Methods Therefore, we conducted semi-structured interviews and applied questionnaires to artisanal fishers of ornamental fish (N = 89), from the municipality of Barcelos, from January to April 2016. Results In total, 41 popular names were cited, which correspond to four ethnocategories and 10 families. The main species were Paracheirodon axelrodi (12.5%), Hemigrammus bleheri (8.3%), Ancistrus dolichopterus (6.4%), Symphysodon discus (5.3%), and Potamotrygon motoro (3.8%). According to the fishers, the species of fish known in the region as “piabas” have a preference for living in clusters (28.9%) and carry out migratory movements (26.1%). The diet of local fish species reported by fisheries is diverse, though mainly based on periphyton (42.2%), and the reproductive cycle directly influenced by the period of flooding of rivers in the region (37.6%) Conclusion Our study revealed that the fishers possess information on the ecological aspects of local ornamental fish species, many of which are consistent with scientific literature. The information presented may assist in the decision-making process for the management of local fishery resources and contribute to the resumption of growth and sustainability in the capture of ornamental fish.

A multi-proxy reconstruction of climate during the late-Pleistocene to early Holocene transition in the northeastern, USA

2021 ◽  
pp. 1-17
Author(s):  
Laurie D. Grigg ◽  
Kevin J. Engle ◽  
Alison J. Smith ◽  
Bryan N. Shuman ◽  
Maximilian B. Mandl
Keyword(s):  
Late Pleistocene ◽  
Climatic Variability ◽  
Warming Trend ◽  
Early Holocene ◽  
Individual Species ◽  
Environmental Preferences ◽  
The North ◽  
Show Evidence ◽  
Dry Conditions ◽  
Components Analysis

Abstract A multiproxy record from Twin Ponds, VT, is used to reconstruct climatic variability during the late Pleistocene to early Holocene transition. Pollen, ostracodes, δ18O, and lithologic records from 13.5 to 9.0 cal ka BP are presented. Pollen- and ostracode-inferred climatic reconstructions are based on individual species’ environmental preferences and the modern analog technique. Principal components analysis of all proxies highlights the overall warming trend and centennial-scale climatic variability. During the Younger Dryas cooling event (YD), multiple proxies show evidence for cold winter conditions and increasing seasonality after 12.5 cal ka BP. The early Holocene shows an initial phase of rapid warming with a brief cold interval at 11.5 cal ka BP, followed by a more gradual warming; a cool, wet period from 11.2 to 10.8 cal ka BP; and cool, dry conditions from 10.8 to 10.2 cal ka BP. The record ends with steady warming and increasing moisture. Post-YD climatic variability has been observed at other sites in the northeastern United States and points to continued instability in the North Atlantic during the final phases of deglaciation.

scholarly journals Demand Subsidy versus Production Regulation: Development of New Energy Vehicles in a Competitive Environment

Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1280
Author(s):  
Zixuan Wang ◽  
Xiuzhang Li
Keyword(s):  
Social Welfare ◽  
Stackelberg Game ◽  
Positive Impact ◽  
Consumer Preference ◽  
Social Planner ◽  
Environmental Preferences ◽  
The Social ◽  
New Energy ◽  
Vehicle Market ◽  
New Energy Vehicles

In the competitive market environment, the growth of new energy vehicles (NEVs) faces many obstacles. Demand subsidy or production regulation-related policies are widely used to promote the development of NEVs. A comparative analysis of the effects of the two types of policies on the competitive vehicle market requires further study. To fill this gap, we investigate which type of policy is more preferable from the perspective of the social planner. In this paper, we construct a Stackelberg game with a welfare-maximizing social planner and two profit-maximizing manufacturers producing NEVs and fuel vehicles (FVs), respectively. Interestingly, although both types of policies can increase the quantity of NEVs, demand subsidy also promotes the growth of total vehicles at the same time; in contrast, production regulation reduces the total vehicles. Moreover, compared with the benchmark that no policy intervention, demand subsidy generally improves social welfare, while production regulation improves social welfare only with high consumer preference for NEVs. Nevertheless, production regulation always has a positive impact on the environment, whereas demand subsidy may have a positive impact only when the NEV is very environment friendly. The numerical results show that consumer environmental preferences and the regulation of environmental impact determine which type of policy dominates the other.

Ecologic significance of post-Palaeozoic green calcareous algae

1978 ◽  
Vol 115 (6) ◽  
pp. 437-442 ◽  
Author(s):  
Graham F. Elliott
Keyword(s):  
Calcareous Algae ◽  
Environmental Preferences ◽  
Independent Evidence ◽  
Taxonomic Relationship

SummaryThe palaeoecologic significance of post-Palaeozoic green calcareous algae is evaluated with what is known of the environments of comparable living algae. Here requirements and tolerances of temperature, bottomsediment, salinity and water-energy may be observed; depth is apparently significant only as it influences these. In the extinct algae, only a minority show clear taxonomic relationship to living algae, in palaeo-environmentsdeduced from independent evidence. Codiaceae and Dasycladales seem to have had environmental preferences like their living descendants, with preferredmicroenvironments in some genera.

Floristic variation across 600 km of inundation forests (Igapó) along the Negro River, Central Amazonia

Hydrobiologia ◽  
2012 ◽  
Vol 729 (1) ◽  
pp. 229-246 ◽  
Author(s):  
Juan Carlos Montero ◽  
Maria Teresa Fernandez Piedade ◽  
Florian Wittmann
Keyword(s):  
Negro River ◽  
Inundation Forests ◽  
Central Amazonia ◽  
Floristic Variation

Hydrochemical aspects of the negro river, patagonia, argentina

1980 ◽  
Vol 5 (2) ◽  
pp. 181-186 ◽  
Author(s):  
Pedro J. Depetris
Keyword(s):  
Negro River

Residential Environmental Preferences and Choice: Empirically Validating Preference Measures

1972 ◽  
Vol 4 (4) ◽  
pp. 445-458 ◽  
Author(s):  
M Menchik
Keyword(s):  
Natural Environment ◽  
Residential Choice ◽  
Lot Size ◽  
Environmental Preferences ◽  
Residential Preferences ◽  
Suburban Sprawl ◽  
Market Choice ◽  
Residential Characteristics ◽  
Spread Pattern

In order to evaluate demands for new forms of residential environments (such as cluster development rather than the spread pattern of suburban sprawl), it may be useful to deal with persons' residential preferences directly, rather than their market choice. The paper develops residential environmental preference variables from questionnaire survey data. The preferences may be considered as relative tradeoffs among the residence's accessibility, characteristics of the house and lot (for example, lot size), the quality of the natural environment, and characteristics of the non-natural environment (for example, population density). At the same time, comparable measures are devised of the characteristics of the persons' present residences—their residential choice. Principal results are that the preference and choice variables do seem useful; that preferences, thus defined, do express themselves to some extent through market choice; and that different persons do in fact prefer different residential characteristics. Preferences for different residential characteristics tend to be negatively associated, so that there are persons with strong preferences for the natural environment who are willing to sacrifice a large lot to live in a beautiful area.

Finding the appropriate variables to model the distribution of vector-borne parasites with different environmental preferences: climate is not enough

2013 ◽  
pp. n/a-n/a ◽  
Author(s):  
Antón Pérez-Rodríguez ◽  
Sofía Fernández-González ◽  
Iván de la Hera ◽  
Javier Pérez-Tris
Keyword(s):  
Environmental Preferences ◽  
Vector Borne
Sign in / Sign up

Export Citation Format

Share Document