Search results for "ck"
showing 10 items of 18632 documents
Ecosystem processes are rarely included in tactical fisheries management
2015
Fish stock productivity, and thereby sensitivity to harvesting, depends on physical (e.g. ocean climate) and biological (e.g. prey availability, competition and predation) processes in the ecosystem. The combined impacts of such ecosystem processes and fisheries have lead to stock collapses across the world. While traditional fisheries management focuses on harvest rates and stock biomass, incorporating the impacts of such ecosystem processes are one of the main pillars of the ecosystem approach to fisheries management (EAFM). Although EAFM has been formally adopted widely since the 1990s, little is currently known to what extent ecosystem drivers of fish stock productivity are actually imp…
Is in vitro micrografting a possible valid alternative to traditional micropropagation in Cactaceae? Pelecyphora aselliformis as a case study
2016
Several taxa of Cactaceae are endangered by overcollection for commercial purposes, and most of the family is included in the Convention on International Trade in Endangered Species of Fauna and Flora (CITES). Micropropagation may play a key role to keep the pressure off wild populations and contribute to ex situ conservation of endangered taxa. One of the limits of micropropagation is the species-specific requirement of plant regulators for each taxon and sometimes even for different genotypes. With the micrografting technique the rootstock directly provides the scion with the necessary hormonal requirements. In this paper we present data on in vitro grafting of Pelecyphora aselliformis Eh…
An updated checklist of the vascular flora native to Italy
2018
AbstractAn updated inventory of the vascular flora alien to Italy, providing details on the occurrence at regional level, is presented. The checklist includes 1597 species, subspecies, and hybrids, distributed in 725 genera and 152 families; 2 taxa are lycophytes, 11 ferns and fern allies, 33 gymnosperms, and 1551 angiosperms. 157 taxa are archaeophytes and 1440 neophytes. The alien taxa currently established in Italy are 791 (570 naturalized and 221 invasive), while 705 taxa are casual aliens, 4 are not assessed, 7 are of unknown regional distribution, 47 have not been confirmed in recent times, 3 are considered extinct or possibly extinct in the country, and 40 are doubtfully occurring in…
Decoding Group Vocalizations: The Acoustic Energy Distribution of Chorus Howls Is Useful to Determine Wolf Reproduction
2016
Population monitoring is crucial for wildlife management and conservation. In the last few decades, wildlife researchers have increasingly applied bioacoustics tools to obtain information on several essential ecological parameters, such as distribution and abundance. One such application involves wolves (Canis lupus). These canids respond to simulated howls by emitting group vocalizations known as chorus howls. These responses to simulated howls reveal the presence of wolf litters during the breeding period and are therefore often used to determine the status of wolf populations. However, the acoustic structure of chorus howls is complex and discriminating the presence of pups in a chorus i…
Factors affecting population dynamics of Eurasian woodcocks wintering in France: assessing the efficiency of a hunting-free reserve
2005
International audience; The Eurasian woodcock Scolopax rusticola is a migratory bird of major importance for hunting, which is susceptible to habitat loss and the stochastic effects of severe winter weather. Conservation issues mostly concerned regulation of hunting, but the efficiency of hunting-free reserves has never been investigated. We studied causes of mortality and survival probabilities of 98 radio-tagged woodcocks in a reserve with no hunting and in an adjoining hunting area in Brittany (France). Predation, mostly by mammalian predators on fields at night, was similar among adults and yearlings, while hunting mortality was more important in yearlings. Overall winter survival proba…
Paraplangia sinespeculo, a new genus and species of bush-cricket, with notes on its biology and a key to the genera of Phaneropterinae (Orthoptera: T…
2018
Madagascar is a well-known hotspot of biodiversity. However, many Orthoptera, and especially the Tettigonioidea, belong to little-studied groups. Here we describe a new genus and species of bush-cricket reared from field-collected eggs.Paraplangiasinespeculogen. nov., sp. nov. belongs to Phaneropterinae and shares diagnostic characteristics with members of the tribe Amblycoryphini and its African subtribe Plangiina stat. nov.Paraplangia, which has a chromosome number of 31 X0, differs from other African members of the tribe and subtribe such asEurycoryphaandPlangia, which both have 29 X0. In addition to morphology, we describe the male calling song, female acoustic response, and mating beha…
Natural Forest Management in Neotropical Mountain Rain Forests — An Ecological Experiment
2008
In tropical forests, the first step in the destruction cycle is usually the over-exploitation of high value timber, leading not only to extinction of the extracted species (Silva Matos and Bovi 2002) but also to the conversion of the forests into pastures in many cases (Wunder 1996b). In many highlands of Ecuador the productivity of the pastures is depleted due to the invasion of bracken fern (see Chapter 28 in this volume), which finally leads again to the conversion of primary forests by local farmers (Paulsch et al. 2001; Hartig and Beck 2003). This process usually is accompanied by loss of biodiversity (Brooks et al. 200 I), increased erosion, changes of hydrology (Bruijnzel 2004), and …
Study of a New Population of the Argentinian Endemic Species Riella choconensis Hässel (Riellaceae, Marchantiophyta) Reveals a Novel Anatomical Struc…
2019
A new population of the Argentinian endemic Riella choconensis Hässel (Riellaceae, Marchantiophyta) was discovered from a culture of sediments from the Laguna de los Juncos (Río Negro province, Argentina). This species was known previously from two nearby collections, made in 1984, in the type locality at the Ramos Mexía reservoir (Neuquén province) and was not recorded since. Fresh material from the new population enabled detailed morphological analyses, which are extensively described here, illustrated and compared to type material of the species. Based on the smooth female involucre, the species belongs to subgenus Riella Mont. However, cross-sections of this structure showed that R. cho…
Fitness of backcross six of hybrids between transgenic oilseed rape (Brassica napus) and wild radish (Raphanus raphanistrum
2002
The process of introgression between a transgenic crop modified for better agronomic characters and a wild relative could lead potentially to increased weediness and adaptation to the environment of the wild species. However, the formation of hybrid and hybrid progeny could be associated with functional imbalance and low fitness, which reduces the risk of gene escape and establishment of the wild species in the field. Our work compares the fitness components of parents and different types of backcross in the sixth generation of hybrids between transgenic oilseed rape (Brassica napus, AACC, 2n = 38) resistant to the herbicide glufosinate and wild radish (Raphanus raphanistrum, RrRr, 2n = 18)…
The genome sequence of the grape phylloxera provides insights into the evolution, adaptation, and invasion routes of an iconic pest
2020
Background: Although native to North America, the invasion of the aphid-like grape phylloxera Daktulosphaira vitifoliae across the globe altered the course of grape cultivation. For the past 150 years, viticulture relied on grafting-resistant North American Vitis species as rootstocks, thereby limiting genetic stocks tolerant to other stressors such as pathogens and climate change. Limited understanding of the insect genetics resulted in successive outbreaks across the globe when rootstocks failed. Here we report the 294-Mb genome of D. vitifoliae as a basic tool to understand host plant manipulation, nutritional endosymbiosis, and enhance global viticulture. Results: Using a combination of…