scholarly journals Does seed aggrupation and substrate type affect the germination on three native species of Durango, Mexico?

Phyton ◽  
2018 ◽  
Vol 87 (1) ◽  
pp. 252-259
Author(s):  
S醤chez J ◽  
J S醗nz Mata ◽  
J Flores ◽  
E Jurado ◽  
E Estrada Castill髇 ◽  
...  
Keyword(s):  
Native Species ◽  
Substrate Type

scholarly journals Ekologi dan Kelimpahan Ikan Sentani Gudgeon (Oxyeleotris heterodon, Weber 1908) dan Snakehead Gudgeon (Giuris margaritacea, Valenciennes 1837) di Danau Sentani, Papua

2019 ◽  
Vol 11 (1) ◽  
pp. 24-32
Author(s):  
Henderite L. Ohee ◽  
Gerardinalia Ngamelubun ◽  
Joane J. Ansaka ◽  
Novela H. Korwa ◽  
Puguh Sujarta
Keyword(s):  
Native Species ◽  
Fish Abundance ◽  
Lake Area ◽  
Substrate Type ◽  
Habitat Depth ◽  
Dense Water ◽  
Substrate Preferences ◽  
Type Water ◽  
Freshwater Community ◽  
Water Vegetation

Freshwater community in Lake Sentani comprise of 35 species including three endemic species, seven native species, eight anadromous fish and 17 introduced species. Two native species are Sentani Gudgeon (Oxyeleotris heterodon) and Snakehead Gudgeon (Giuris margaritacea). The survey aims to document the ecology and fish abundance of the gudgeons in Lake Sentani. Fish sampling was done passively by using gill nets with three different mesh sizes in five locations; Puai, Enandowai, Waena, Ayapo and Yahim. Substrate type, water vegetations, habitat depth and fish abundance were recorded each locations. Substrate preferences of the gudgeons are sand, mud and gravel, while O. heterodon was more abundance in sand mud substrate type. Moreover, water vegetation preference was different between O. heterodon and G. margaritacea. Sentani Gudgeon prefer habitat with dense water vegetations, while G. margaritaceus could be found in habitat with or without water vegetation. Theses two gudgeons were found in relatively the same habitat depth, up to 7 meters depth. O. heterodon and G. margaritacea had a very low abundance in the lake. It is important to conserve lake area from the edge  up to 7 meter depth that consist of sand, mud and gravel substrate types and dense water vegetation to ensure the population of these two gudgeons are abundance in Lake Sentani.   Key words: Ecology, Lake Sentani, relative abundance, O. heterodon, G. margaritacea.

scholarly journals Green Roof Substrate Type and Depth Affect the Growth of the Native Species Dianthus fruticosus Under Reduced Irrigation Regimens

HortScience ◽  
2011 ◽  
Vol 46 (8) ◽  
pp. 1208-1216 ◽  
Author(s):  
Panayiotis A. Nektarios ◽  
Ioannis Amountzias ◽  
Iro Kokkinou ◽  
Nikolaos Ntoulas
Keyword(s):  
Drought Stress ◽  
Native Species ◽  
Dry Weight ◽  
Green Roofs ◽  
Substrate Type ◽  
Drought Period ◽  
Substrate Moisture ◽  
Soilless Substrate ◽  
Substrate Depth ◽  
Extensive Green Roofs

Extensive green roofs are a promising technology for reintroducing lost flora in degraded urban environments, but further research is needed for their application in semiarid regions. Therefore, research was undertaken to determine the effects of substrate type and depth and the amount of irrigation during a drought period on the establishment, growth, and physiology of the native species Dianthus fruticosus sub. fruticosus. Treatments included two substrate types [a soilless substrate (Pum50:Per20:C20:Z10) or a substrate with soil (S15:Pum40:Per20:C20:Z5), in which Pum = pumice; Per = perlite; C = compost; Z = clinoptinolite zeolite; and S = sandy loam soil, mixed in a volumetric proportion indicated by their subscripts], two substrate depths (7.5 cm or 15.0 cm), and two irrigation regimens during drought [15% or 30% of pan evaporation (Epan)]. Measurements included substrate characteristics such as particle size distribution, dry and saturated bulk density, water characteristic curves, and in situ determination of substrate moisture during drought stress. Plant growth was determined based on biometric measurements such as growth index (GI) and dry weight and physiological indicators such as SPAD, chlorophylla+b, and carotenoid contents. It was found that substrate moisture during drought was increased in the soil substrate compared with the soilless substrate as a result of its better water retention capacity in low tensions. Dianthus fruticosus sub. fruticosus growth was promoted by the deep substrate (15 cm) throughout the entire study, whereas substrate type and irrigation during the drought period did not have an effect. Similarly, leaf dry weight was increased in the deeper substrates, whereas shoot and root dry weights were similar in all treatments. SPAD was found to be a more sensitive method than chlorophyll and carotenoid analysis and revealed an interesting sequence of treatment influences on D. fruticosus sub. fruticosus physiology that depended on the climatic conditions and stress imposition. More specifically, during establishment, both substrate type and depth affected growth with the soil substrate and deep profiles yielding higher SPAD measurements. Soon after the initiation of drought, the deep profiles had higher SPAD values than the shallow ones, whereas in high-irrigation regimens and, to a less extent, deeper profiles provided increased SPAD values after the middle of drought imposition. Chlorophyll and carotenoid levels reduced during the drought stress period, but very limited differences were detected between treatments. It was concluded that D. fruticosus sub. fruticosus is a very promising native plant for use on extensive green roofs in the Mediterranean region, and its growth was better in a substrate depth of 15 cm. However, its growth was sufficient even with a 7.5-cm substrate depth and irrigation of 15% Epan.

Ice-free area expansion compounds the non-native species threat to Antarctic terrestrial biodiversity

2019 ◽  
Author(s):  
Grant Duffy ◽  
Jasmine R Lee
Keyword(s):  
Human Activity ◽  
Native Species ◽  
Climate Scenario ◽  
Climatic Environment ◽  
Species Establishment ◽  
Suitable Habitats ◽  
Terrestrial Biodiversity ◽  
A Site ◽  
Area Expansion ◽  
Free Area

Warming across ice-covered regions will result in changes to both the physical and climatic environment, revealing new ice-free habitat and new climatically suitable habitats for non-native species establishment. Recent studies have independently quantified each of these aspects in Antarctica, where ice-free areas form crucial habitat for the majority of terrestrial biodiversity. Here we synthesise projections of Antarctic ice-free area expansion, recent spatial predictions of non-native species risk, and the frequency of human activities to quantify how these facets of anthropogenic change may interact now and in the future. Under a high-emissions future climate scenario, over a quarter of ice-free area and over 80 % of the ~14 thousand km2 of newly uncovered ice-free area could be vulnerable to invasion by one or more of the modelled non-native species by the end of the century. Ice-free areas identified as vulnerable to non-native species establishment were significantly closer to human activity than unsuitable areas were. Furthermore, almost half of the new vulnerable ice-free area is within 20 km of a site of current human activity. The Antarctic Peninsula, where human activity is heavily concentrated, will be at particular risk. The implications of this for conservation values of Antarctica and the management efforts required to mitigate against it are in need of urgent consideration.

High predatory efficiency and abundance drive expected ecological impacts of a marine invasive fish

2020 ◽  
Vol 637 ◽  
pp. 195-208 ◽  
Author(s):  
EM DeRoy ◽  
R Scott ◽  
NE Hussey ◽  
HJ MacIsaac
Keyword(s):  
Invasive Species ◽  
Native Species ◽  
Ecological Impact ◽  
Marine Species ◽  
Ecological Impacts ◽  
Negative Effects ◽  
Marine Predator ◽  
Eastern Gulf Of Mexico ◽  
Red Grouper ◽  
Per Capita

The ecological impacts of invasive species are highly variable and mediated by many factors, including both habitat and population abundance. Lionfish Pterois volitans are an invasive marine species which have high reported detrimental effects on prey populations, but whose effects relative to native predators are currently unknown for the recently colonized eastern Gulf of Mexico. We used functional response (FR) methodology to assess the ecological impact of lionfish relative to 2 functionally similar native species (red grouper Epinephelus morio and graysby grouper Cephalopholis cruentata) foraging in a heterogeneous environment. We then combined the per capita impact of each species with their field abundance to obtain a Relative Impact Potential (RIP). RIP assesses the broader ecological impact of invasive relative to native predators, the magnitude of which predicts community-level negative effects of invasive species. Lionfish FR and overall consumption rate was intermediate to that of red grouper (higher) and graysby grouper (lower). However, lionfish had the highest capture efficiency of all species, which was invariant of habitat. Much higher field abundance of lionfish resulted in high RIPs relative to both grouper species, demonstrating that the ecological impact of lionfish in this region will be driven mainly by high abundance and high predator efficiency rather than per capita effect. Our comparative study is the first empirical assessment of lionfish per capita impact and RIP in this region and is one of few such studies to quantify the FR of a marine predator.

Endangered Butterflies and their Non-Native Host Plants: Examining Shifting Values of Belonging in Restoration

2019 ◽  
Vol 3 (1) ◽  
pp. 1-9
Author(s):  
Robert M. Anderson ◽  
Amy M. Lambert
Keyword(s):  
Ecological Restoration ◽  
Native Species ◽  
Puget Sound ◽  
A Value ◽  
The Social ◽  
Remote Island ◽  
Scientific Truth ◽  
Native Host

The island marble butterfly (Euchloe ausonides insulanus), thought to be extinct throughout the 20th century until re-discovered on a single remote island in Puget Sound in 1998, has become the focus of a concerted protection effort to prevent its extinction. However, efforts to “restore” island marble habitat conflict with efforts to “restore” the prairie ecosystem where it lives, because of the butterfly’s use of a non-native “weedy” host plant. Through a case study of the island marble project, we examine the practice of ecological restoration as the enactment of particular norms that define which species are understood to belong in the place being restored. We contextualize this case study within ongoing debates over the value of “native” species, indicative of deep-seated uncertainties and anxieties about the role of human intervention to alter or manage landscapes and ecosystems, in the time commonly described as the “Anthropocene.” We interpret the question of “what plants and animals belong in a particular place?” as not a question of scientific truth, but a value-laden construct of environmental management in practice, and we argue for deeper reflexivity on the part of environmental scientists and managers about the social values that inform ecological restoration.

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