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91.
We assessed vegetation recovery on access roads removed after well abandonment in an active oil‐producing region of northern Great Plains grasslands. We compared extant vegetation on 58 roads, restored 3–22 years previously, to records of species seeded on each and to adjacent, undisturbed prairie, to evaluate main differences between the restored and adjacent community and to explore patterns in the restored plant community over time. The restored plant community was dominated by low richness of seeded non‐native and native grasses and forbs, whereas adjacent prairie had numerous, abundant native graminoids and shrubs and higher richness of native forbs. Cover of seeded species on roads was double that of colonizing species. Disparity in cover of dominant native grasses between the adjacent community and relatively narrow restored roadway suggests that conditions for germination and survival in roadbeds are poor. This is at least partly due to persistence of seeded species. Differences in restored plant composition over time were best explained by changes in species seeded, from non‐natives to natives, and secondarily by successional shifts from ruderal to perennial non‐seeded species. Of the 30 species seeded at least once on these roads, only 10 were commonly used. The long‐term influence of seeding choices in grassland road restorations implies that improvements in these practices will be critical to reversing ecological impacts of roads. 相似文献
92.
Navet R Jarmuszkiewicz W Douette P Sluse-Goffart CM Sluse FE 《Journal of bioenergetics and biomembranes》2004,36(5):471-479
We have previously shown that a kinetic interplay exists between the cytochrome pathway and the alternative oxidase in mitochondria from amoeba Acanthamoeba castellanii . Native interaction analyses using blue native gel electrophoresis coupled to denaturating electrophoresis and immunodetection have indicated associations between alternative oxidase and oxidative phosphorylation complexes in both amoeba and tomato mitochondria. These associations are dependent on the expression level of alternative oxidase according to the physiological state in both organisms. Alternative oxidase associates broadly with large complexes of the respiratory chain when it is expressed in large amount, i.e., in ripe tomato and exponentially growing amoeba. On the contrary, alternative oxidase interacts specifically with complex III even if expression of the oxidase is low, i.e., in green tomato and stationary phase amoeba. This specific interaction represents a higher level of regulation driven by protein-protein interactions leading to a direct kinetic interplay between the cytochrome pathway and alternative oxidase in both plant and amoeba mitochondria. 相似文献
93.
Introduced rats are now being eradicated from many islands. Increasingly, these eradications are contested by activists claiming moral, legal, cultural, historic or scientific reasons and poorly documented evidence of effects. We reviewed the global literature on the effects of rats on island flora and fauna. We then used New Zealand as a case study because of its four-decade history of rat eradications and many detailed and innovative studies of how rats affect native species. These include use of exclosures, local manipulations of rat populations, video surveillance, and measurements of responses following eradications. The most intensive studies have been on the Pacific rat (Rattus exulans), a small South-East Asian species spread by Polynesians throughout the Pacific. These and the more recently introduced Norway rat (R. norvegicus) and ship (roof) rat (R. rattus) suppress some forest plants, and are associated with extinctions or declines of flightless invertebrates, ground-dwelling reptiles, land birds, and burrowing seabirds. On islands off France, Norway rats are also implicated in declines of shrews. Globally, ship rats were associated with declines or extinctions of the largest number of indigenous vertebrate species (60), including small mammals such as deer mice and bats. Effects of rats on forest trees and seabird populations are sufficiently pervasive to affect ecosystem structure and function. However, the data are patchy. Deficiencies in our knowledge would be reduced by documenting distribution and abundance of indigenous species before and after eradications. Comprehensive measurements of the responses of indigenous species to rat eradications would enable the development of testable models of rat invasion effects. 相似文献
94.
Farid Bounaceur Naceur Benamor Fatima Zohra Bissaad Faten Lasgaa Sabah Baghadid Faiza Rezigua Stéphane Aulagnier 《African Journal of Ecology》2023,61(1):28-36
The feeding ecology of the aoudad (Ammotragus lervia) was investigated for the first time in north-western Sahara, Djebel Antar (Bechar province, Algeria), from autumn 2015 to summer 2016. Microhistological analyses of faeces revealed an annual diet composed of 23 identified taxa belonging to 16 plant families. The highest species diversity was recorded in spring and summer (23 species), despite a marked consumption of two species: Vachellia tortilis (17.7%) and Avena sterilis (14.0%); diet diversity was lower in autumn and winter (16 species), including mainly Teucrium polium (14.7%, 21.0%) and Gymnocarpos decander (19.7%, 10.0%). The main plant parts consumed during these seasons were stems (77.7%, 65.3%), while leaves and inflorescences were mostly consumed during spring and summer (54.7%, 52.3%). Forbs dominated the aoudad's diet, with 46.3% average relative abundance, including mainly T. polium, Limoniastrum feei, and Chrysanthemum macrocarpum. Woody plants including mainly V. tortilis and G. decander accounted for 33.3% (50.0% in autumn), and grasses including A. sterilis and H. murinum for 20.4% (32.0% in summer). Based on this diet, A. lervia can be classified as a “generalist mixed-feeder.” 相似文献
95.
在黄土丘陵区草原带、森林草原带和森林带3个植被带选取成对的刺槐群落和乡土植物群落功能性状值,研究不同植被带刺槐群落、乡土植物群落功能结构的变化,以及同一植被带下刺槐的引入对群落功能结构的影响.结果表明: 刺槐群落和乡土植物群落的叶碳、叶氮、叶磷、比叶面积、叶组织密度等功能性状随植被带的变化规律一致.刺槐群落叶碳、叶氮、比叶面积显著高于乡土植物群落,且2种群落功能多样性指数(FRic、FEve、FDiv、FDis、Rao)随植被带的变化趋势并不完全一致,在森林带刺槐的引入提高了植物群落功能多样性,在草原带降低了植物群落功能多样性. 相似文献
96.
Top predator fish assemblages in Northern Patagonia,Argentina. What factors regulate their patterns of distribution and abundance? 下载免费PDF全文
María Valeria Fernández Mailén Lallement Magalí Rechencq Pablo H. Vigliano Alejandro Sosnovsky Patricio J. Macchi 《Austral ecology》2018,43(6):651-662
According to assemblage theory, three factors regulate fish biogeography: restriction of dispersion, environmental restrictions and biotic interactions. The first two factors act on a regional scale and delimit the area of action of the third, which operates on a local scale. Salmonid introductions began in Patagonia in 1904, and this has led to a restructuring of trophic webs and an increase in the number of top predators. This situation allowed us to evaluate, in a natural setting, how communities are formed on different geographic scales. We studied two large basins in Patagonia, situated close to each other but with different assemblages of top predatory fish. We hypothesized that differences in the structuring of the top predator assemblages between and within the basins are due to 1) environmental factors and dispersion processes facilitated by connectivity on a regional scale; and 2) biotic interaction (internal dynamics) between native perch and salmonids, the former acting as a modulator of the top predator assemblages on a local scale. To test these hypotheses, we analysed the top predator assemblages of 16 lakes and one reservoir, as well as their environmental characteristics. We performed a cluster analysis and related the resulting assembly groups to environmental factors by means of a tree model. We also analysed fish diets, using a similarities test to study biotic interactions. On regional and local scales, water basin, degree of connectivity, area, temperature and Zoogeographic integrity coefficient (ZIC) were important factors in the structuring of top predator assemblages. On a local scale, creole perch modulates the salmonid populations through feeding and the consequent distribution of resources. Our work showed that the structure of top predator assemblages was determined by a combination of local and regional factors acting in synergy, as postulated by the assemblage theory. 相似文献
97.
Dubrovskaya VV Andryushkova AS Kuznetsova IA Toporkova LB Buneva VN Orlovskaya IA Nevinsky GA 《Biochemistry. Biokhimii?a》2003,68(10):1081-1088
Catalytically active antibodies (abzymes) hydrolyzing proteins, polysaccharides, ATP, DNA, and RNA have been detected in the sera of patients with various autoimmune and some viral diseases, but abzymes from the sera of animals are practically unstudied. The development of lupus-like autoimmune disease of MRL/MpJ-lpr mice is an experimental model for study of autoimmune pathologies and immunopathogenesis. In this work, homogeneous IgG preparations were isolated from the sera of MRL/MpJ-lpr mice. These antibodies (Abs), their Fab-fragments, and isolated light chains were shown to possess catalytic activity in DNA hydrolysis, whereas Abs from the sera of control healthy mice did not hydrolyze DNA. The data demonstrate that DNA hydrolyzing activity is an intrinsic property of Abs from MRL/MpJ-lpr mice. It was shown that various markers of autoimmune pathologies (level of total protein concentration in urea (proteinuria), Abs titers to native and denatured DNA, and DNA-hydrolyzing activity of IgG) increased in animals with aging, but they noticeably increased (2-22 times) only after appearance of obvious indicators of pathology independently of age. The highest increase in proteinuria (25-fold), anti-DNA Abs titers (12-19-fold), and abzyme activity (120-fold) was found in mice after their immunization with DNA–protein complex. 相似文献
98.
99.
Natalia B. ANANJEVA ;Evgeny A. GOLYNSKY ;Seyyed Saeed HOSSEINIANYOUSEFKHANI ;and Rafaqat MASROOR 《亚洲两栖爬行动物研究(英文版)》2014,(3):161-167
Predictive potential distribution modeling is of increasing importance in modern herpetological studies and determination of environmental and conservation priorities. In this article we provided results of analysis and forecasts of the potential distribution of smallscaled rock agama Paralaudakia microlepis (Blanford, 1874) using the distribution models through Maxent (www.cs.princeton.edu/- schapire / maxent). We made an attempt for comparison of input of bioclimatic factors and characteristics of biotope distribution for three species of genus Paralaudalda. Constructed model identified dissemination of Paralaudakia microlepis enough performance (AUC = 0.972 with dispersion 0.003). According to the map constructed, the most suitable habitats of smallscaled rock agama Paralaudakia microlepis are located in southern and eastern Iran, the west of central Pakistan and southeastern Afghanistan. 相似文献
100.
Free Flow Electrophoresis (FFE) is a liquid-based isoelectric focusing method. Unlike conventional in-gel fractionation of proteins, FFE can resolve proteins in their native forms and fractionation of subcellular compartments of the cell is also possible. To test the efficacy of the FFE method, the native cytosol proteome of a bacterium, Pseudomonas putida KT2440 was fractionated by FFE and the spectrum of protein elutes was characterized in association with 2-dimentional gel electrophoresis (2-DE). Major native proteins of P. putida KT2440 were eluted in the range of pH 4.8 approximately 6.0 in FFE, whereas the denatured proteome of P. putida KT2440 was widely distributed in the rage of pH 4 approximately 10 in the 2-DE analysis. In addition, one of the three FFE major fractions, which was eluted at pH 5.0, was further analyzed using 2-DE/MS-MS. Then, the pH range of identified proteins eluted in 2-DE/MS-MS was 4.72 approximately 5.89, indicating that observed pi values of native cytosolic proteomes in FFE were narrower than those of denatured cytosolic proteome. These results suggest that FFE fractionation and 2-DE/MS analysis may be useful tools for characterization of native proteomes of P. putida KT2440 and comparative analysis between denatured and native proteomes. 相似文献