Miracle-dz/UniFAR-FTUs huggingface dataset:
The Endangered Siberian marmot Marmota sibirica as a keystone species? Observations and implications of burrow use by corsac foxes Vulpes corsac in Mongolia

Abstract The Siberian marmot Marmota sibirica is a social, colonial-living rodent that ranges widely throughout northern Asia. In Mongolia the species has declined substantially in recent years due to overharvesting for fur, meat and body parts, used locally and traded illegally in international markets. The Siberian marmot is often considered a keystone species because its burrows appear to represent an important resource for a variety of taxa, including carnivores. However, few studies have quantified marmot burrow use by other species, although such use may be important for developing conservation strategies. We monitored patterns of burrow use by 10 radio-collared corsac foxes Vulpes corsac during a study in Mongolia during May–November 2006. Corsacs used marmot burrows regularly and at rates greater than expected by chance, suggesting that burrows represent an important resource for foxes and supporting the notion of the Siberian marmot as a keystone species. As corsacs are also declining in Mongolia we contend that targeted patrols of marmot colonies in certain areas would provide a cost-effective means of protecting both species.
Variant effects of arsenic compounds on crude oil bioremediation by crude oil-degrading bacteria in Kuwait

Crude oil spills into the environment such as that of Kuwait cause health and ecological problems which necessitates the cleanup of such pollution by efficient methods such as bioremediation. However, the associated heavy metals such as arsenic with crude oil pollution exert inhibitory effects on bioremediating agents for instance soil microbiota leading to hindered bioremediation. In the current study, the tolerance of two dominant crude oil-degrading bacteria in Kuwaiti soil, Acinetobacter spp. a Gram-negative bacteria and Nocardia spp. a Grampositive bacteria, to varying concentrations of arsenate and arsenite was investigated. Results showed the higher potentials of Nocardia spp. to resist the inhibitory effects of added arsenic compounds. Also, arsenite demonstrated significantly higher inhibitory effects on bacterial growth and activity compared to those of arsenate. Additionally, determination of the crude oil mineralization potentials of isolated bacteria demonstrated the significantly higher potentials of Nocardia spp. to mineralize crude oil in presence of arsenic compounds. Moreover, the phylogenetic assessment of isolated strains of Acinetobacter and Nocardia using 16S-RFLP analyses showed the higher diversity of Nocardia strains compared to Acinetobacter. Thus, this study demonstrated the variant effects of arsenic species on the growth and activity of different crude oil-degrading bacteria. Also, results indicated that, the potential of crude oildegrading bacteria to tolerate the inhibitory effects of heavy metals, such as arsenic, could accelerate the bioremediation of crude oil pollution.
Phylogeographic relationships within the Mediterranean turbot inferred by mitochondrial DNA haplotype variation

The Mediterranean turbot Psetta maxima consists of two main genetically distinct lineages (western Mediterranean and ‘eastern secluded Mediterranean’ basins) as investigated by mitochondrial DNA analysis. Within the latter lineage, most haplotypes from the Sea of Azov were endemic and more than half of them derived from a single ancestral haplotype shared among all the eastern Mediterranean areas. There was no relation between morphotype variation in bony tubercles and mitochondrial genealogy.
A karyomorphological study on two newly recorded taxa of Lycoris (Amaryllidaceae) in Anhui province, China1*

Abstract Two wild populations of L. houdyshelii and L. straminea were first discovered in Anhui province and cytologically studied. The results showed that two kinds of cytology were found in L. houdyshelii, with one having the karyotype 2n = 31=3m+13st+10t+5T, and the other having the karyotype 2n = 30=3m+21st (SAT) +3t (SAT) +3T. The karyotypes and secondary constriction are reported for the first time. The karyotype of L. straminea is formulated as 2n = 19=3m+7st+4t+5T, which is similar to some previous reports and confirmed here. The karyotypes of these two taxa are both of 3B type according to the degree of asymmetry and Stebbins’ criteria. According to the gross floral morphology, phenology and karyotype of these two taxa, it is suggested that L. houdyshelii is probably a hybrid between a taxon with 2n = 6M+10T, such as L. longtuba or L. chinensis and L. radiata var. pumila, and L. straminea putatively originates in hybridization between L. radiata var. pumila and L. chinensis.
Population Tracking of Fluctuating Environments and Natural Selection for Tracking Ability

The mathematics of stochastic nonlinear population models is notoriously intractable and has led some investigators to study linear approximations to make computations easier. However, nonlinear models may often better describe biological systems, and linearization may obscure dynamics of biological significance. We clarify various aspects of the dynamics of the logistic population model with a fluctuating carrying capacity. Average population size decreases with an increasing magnitude of variation in K, but N̄ is always less than or equal to K̄. This effect is mediated by the intrinsic rate of increase, r. In general, N̄ increases as r increases. This pattern should be general for models where N is a concave function of N. In environments where the magnitude of variation in K is not large, natural selection will favor genotypes which are best able to track fluctuations in K. However, when the fluctuations in K are large, natural selection may favor forms which are not highly responsive to fluctuations in K.
The fuzzy structure of populations

The human perception of biological organization has profound implications for the study, management, and conservation of living things. Traditional methods of classification, which imply all-or-nothing group membership, are inconsistent with the modern synthesis, which stresses variability and unique individuals. We propose that fuzzy classification, which allows fractional membership in multiple clusters, can more realistically denote many forms of biological organization, such as populations. We used fuzzy clustering to depict the ambiguous structure of a migratory caribou (Rangifer tarandus) herd, based on affinities in space use, and walleye (Stizostedion vitreum) stocks, based on genetic dissimilarities among multilocus genotypes. In both cases, fuzzy memberships conveyed the degree of uncertainty of belonging while resolving cluster memberships for unambiguous and problematic individuals. Vagueness implies that borderline group identity cannot be remedied with more resolving power. Fuzzy classificat.
Species delimitation in the leaf beetle genus Macroplea (Coleoptera, Chrysomelidae) based on mitochondrial DNA, and phylogeographic considerations

The genus Macroplea Samouelle, 1819 is a group of highly specialized aquatic leaf beetles occurring in the Palaearctic. Since the members of this genus are morphologically very similar, we addressed the question of species identification and delimitation by analysing the second half of the mitochondrial gene coding for the cytochrome oxidase I (COI) subunit. Species limits are inferred from the multimodal frequency distribution of genetic distances between specimens: low genetic distances within a species are clearly set apart from distances between species. The species status of the hitherto controversial species M. japana (Jacoby, 1885) is confirmed. The pattern of nucleotide and amino acid substitutions is discussed in the light of functional domains of the COI molecule. Although the data are preliminary, the results provide new data on the distribution of the species. Together with the phylogenetic analysis they allow for a discussion of the phylogeography of the genus.
STOMACH CONTENTS AND MICROFEEDING OF SOME COMMON CIRRIPEDES

An account is given of the stomach contents of some common barnacles; these include both intertidal and sublittoral species. The contents reflect to some extent the environment, species taken from the same place at the same time having similar contents. With some species, a particle size analysis was possible on a pooled sample of stomach contents. It is evident that much debris is present, and that particulate matter with a diameter less than 2 μ can be taken. Detritus may be an important source of nutriment with sublittoral species. Small particles cannot be taken by the captorial activity of the cirri. It is considered that glandular secretions at the base of the cirri, where there are numerous setae, enmesh the food, which is then carried forward to the mouth parts to be rejected or accepted.
Population dynamics and nitrogen allocation of Sonchus arvensis L. in relation to initial root size

To develop better mechanical management strategies, more information on the impact of root partitioning on changes in the population dynamics of Sonchus arvensis is needed. Therefore, the effects of root fragmentation of S. arvensis on shoot height frequency distributions, biomass production and nitrogen allocation were studied in an outdoor experiment in Sweden in 2008. Three artificial populations of S. arvensis of different initial root lengths but with the same total root length per area were planted. Shoot heights were measured at the onset of flowering and dry weight and nitrogen content of leaves, stems, buds and roots were quantified twice during the season. Height frequency distributions of the populations were bimodal, indicating the existence of two generations distinctly different in height growth pattern. Shorter root fragments produced shoots with a lower mean height compared to longer fragments. Plants originating from longer root fragments had higher dry weight and more nitrogen compared to plants from shorter root fragments. Dry matter production per square meter did not differ between the populations. The proportion of dry matter and nitrogen allocated to the different plant components (leaves, stems, buds and roots) at harvest did not differ between the populations. Over time, nitrogen was reallocated from leaves and stems to roots. Our results show that initial root length of S. arvensis per square meter, rather than the number of root fragments per square meter, is a good predictor of biomass at harvest, and that the degree of root fragmentation does not affect nitrogen allocation patterns. Root fragmentation, however, leads to a lower average canopy height for S. arvensis, and thus may be an effective weed control measure in combination with a crop which is competitive for light.
PHOSPHORUS ACQUISITION FROM COMPACTED SOIL BY HYPHAE OF A MYCORRHIZAL FUNGUS ASSOCIATED WITH RED CLOVER (TRIFOLIUM PRATENSE)

The influence of an arbuscular mycorrhizal fungus, Glomus mosseae, on the adverse effects of soil compaction on growth and phosphorus (P) uptake of red clover was studied in a model experiment. The pots used in the experiment had three compartments, a central one with a soil bulk density of 1.3 g ∙ cm−3 and two outer compartments with three different levels of soil bulk density (1.3, 1.6, or 1.8 g ∙ cm−3). The soil in the outer compartments was fertilized with P and was either freely accessible to roots and hyphae, or separated by nets and accessible to hyphae only. At a soil bulk density of 1.3 g ∙ cm−3, mycorrhizal plants did not absorb more P than nonmycorrhizal plants except when access of roots to the outer compartments was restricted by nets. At high soil bulk density, root growth was drastically decreased. However, hyphae of G. mosseae absorbed P even from highly compacted soil, and induced a P-depletion zone of about 30 mm from the root surface. In consequence, at higher soil bulk density shoot P .
Responses of old and modern cereals to CO2-fertilisation

Abstract. Increases in atmospheric CO2 had impacts on plant evolution throughout geological times and enabled mass selection of productive crop ancestors. Recent studies suggest that the ongoing CO2 fertilisation justifies the establishment of breeding programs to develop crops whose yield will profit from the greater availability of carbon without compromising seed quality. It has been shown that old cultivars may respond more strongly to CO2 enrichment than their modern counterparts. In order to address this issue, old and modern cereal cultivars (wheat, spelt, barley and rye) and ancestors of wheat (Aegilops, einkorn, emmer) were grown at ambient (380 ppm) and expected future (550 ppm) concentrations of CO2 in growth chambers simulating a seasonal climate typical for south-west Germany. Phenology, senescence, growth, yield formation and seed quality (ash and nitrogen (N) concentrations) were assessed and the CO2 response ratio (RR, i.e. performance under elevated v. ambient CO2) of the parameters was evaluated with respect to the year of cultivar release. Across the 32 accessions tested, seed mass increased by 34% under elevated CO2, whereas seed ash and N concentrations decreased by 8 and 10%, respectively, with large inter- and intra-specific variation. Yields of modern wheat and barley cultivars proved higher than of old cultivars, but only in barley was RR higher in the older cultivars. Some accessions showed deviations from the negative relationship between seed mass and N concentration, rendering them suitable candidates for developing cultivars adapted to high CO2.
Influence of N, P, and K Fertilization on Yield and Mineral Composition of Native Bluejoint Grass on the Lower Kenai Peninsula, Alaska1

Domestic grasses are difficult to establish and maintain in the Caribou Hills of the lower Kenai Peninsula in Alaska. Thus this 8-year study sought to determine native bluejoint [Cufurnugrostis cunadensis (Michx.) Beauv. ] response to varying N, P, and K fertilization rates applied annually and stand persistence when two cuttings were made each growing season. A 4 × 2² factorial experiment with four N rates (67,134,201, and 268 kg N/ha) and two P and K rates (84 and 168 kg P/hq 93 and 186 kg K/ha) was established on Kachemak silt loam (thixotropic over loamy, mixed Typic Cryandept) at 366 m elevation. Concentrations of NO₃₋N, total N, P, K, S, Ca, Mg, and Si in the plants were determined and uptake of these constituents calculated, During this 8 years with two annual harvests and with fertilization the bluejoint stand became more dense. Each increasing N rate through 134 kg/ha generally increased the annual yield. Concentrations of N0₃₋N and total N in both cuttings and annual N uptake were increased by each increasing N increment while the Si concentration of each cutting was depressed. Significant yield interaction between N and K occurred with greater response to N or K at the higher rates of the other. Application of P increased forage yield, P, Ca, and Mg concentrations, and P, K, S, Ca, and Mg uptake. Doubling the P rate further increased these values. Potassium application increased yield, K concentration, and P, K, and S uptake. Doubling the K rate increased the yield at higher N rates and decreased Ca, Mg, and Si concentrations and uptake. Ranchers in the lower Kenai Peninsula area of Alaska can now be assured native bluejoint can be the most important forage grass to provide supplemental winter livestock feed. Persistent high yields can be maintained with less cost than with any other presently known forage.
Fungicide effect of volatile compounds of Thymus capitatus essential oil

An in vitro test to evaluate the fungitoxic activity of Thymus capitatus essential oil was carried out by observing the growth of Botrytis cinerea and Penicillium italicum on potato dextrose agar (PDA) plates inoculated with 10 μl of a spore suspension. The in vivo efficacy of these compounds was investigated on peel discs of 'Valencia late' orange fruit inoculated with the same quantity of spore suspension. Thymus essential oil inhibits the growth of both B. cinerea and P. italicum . The minimal inhibitory concentration (MIC) was 12 ppm for Botrytis and 25 ppm for Penicillium , while the fungicide concentration was 25 and 50 ppm respectively. SEM observations also indicated that the mycelia of both fungi were severely injured by the application of T. capitatus essential oil.
The feeding ecology of the dingo II. Dietary and numerical relationships with fluctuating prey populations in south‐eastern Australia

The dietary and predator-prey relationships of Canis familiaris dingo were studied for 9 yr at a coastal site and for 1.5 yr at a montane site in south-eastern Australia. The percentage occurrences of items eaten were obtained from faeces, and the abundances of prey by counting water-birds, trapping small mammals, and tracking large and medium-sized mammals on specially prepared soil plots. Dingoes were also estimated by tracking. The diet was broad but predominantly mammalian (23 species). Dietary frequencies were grouped around three weight modes, 0.1, 1.25 and 16 kg, corresponding with bush rat (Rattus fuscipes), ringtail possum (Pseudocheirus peregrinus) and swamp wallaby (Wallabia bicolor). The amplitudes of those frequencies approximately doubled from mode to mode, viz. 4, 13.5 and 28.3%, respectively. Medium-sized mammals have been recognized as the staple prey because of their dependability. Their density estimates fluctuated least among prey-groups, and track records of dingoes in the mountains were significantly related to them. Other categories of prey were supplementary (large mammals), opportune (small mammals) and scavenged. Although there were general tendencies for dietary frequencies to follow prey abundances, significant functional and numerical responses were obtained only for water-birds (coot and swan). Their super-abundance in the mid-years of the coastal study and their highly clumped distribution were the likely causes. Predation was disproportionately severe on mammalian prey-classes after an extensive wildfire at the coastal site. Such predation may have suppressed populations of wallabies and kangaroo for 2 yr until the water-birds became super-abundant. The prevalence of wombats in the mountains may have induced heavy predation upon other less numerous large prey. Concepts of profitability in feeding appear to apply to the dingo more than those of optimization of time or energy. The decline in dingoes was correlated most with long-term declines in water-birds and medium-sized mammals. At the time, abundance estimates of wallabies and kangaroos were increasing and those species increasingly predominated in the diet. The ability to hunt co-operatively was apparently ineffectual in preventing decline in dingo numbers. It is suggested that pack size is related inversely to the level of temporal instability in the environment. Frequent wildfires may prevent staple (mediumsized) and supplementary (large) prey from being abundant simultaneously, a combination thought necessary for large pack size.
Prey selection by North Sea herring (Clupea harengus) with special reference to fish eggs

The herring stock in the North Sea in recent years has recovered to a relatively high biomass, and here we investigate prey selection of individual North Sea herring when population numbers are high. The diet composition, and specifically pelagic fish eggs, was investigated in February 2004. Samples of herring from the International Bottom Trawl Survey were used for stomach analysis, and ichthyoplankton samples from the southern North Sea were used to investigate selection. Crustaceans were the main diet component. The average diameter of the fish eggs recovered from the stomachs was significantly larger than that of the eggs collected in the field. In addition, the frequency at which the latest developmental stages occurred in the herring stomachs was significantly different from the frequency at which these stages were found in the field. This shows selective foraging. There was a relationship between the amount of food and the number of eggs in a herring stomach: the fullest stomachs tended to contain fewer fish eggs. This suggests that herring forage on eggs when other prey are not available. Hence, it is likely that the dynamics of multiple trophic levels influence the ecological impact of a large herring stock on the North Sea ecosystem.
A study of marine benthic algae along a natural carbon dioxide gradient

Some chapters of this thesis were prepared as papers and have now been published: Johnson VR, Brownlee, C, Rickaby REM, Graziano M, Milazzo M & Hall-Spencer, JM (2012a) Responses of marine benthic microalgae to elevated CO2. Marine Biology, DOI: 10.1007/s00227-011-1840-2, Johnson VR, Russell BD, Fabricius KF, Brownlee C, Hall-Spencer JM (2012b). Temperate and tropical brown macroalgae thrive, despite decalcification, along natural CO2 gradients. Global Change Biology 18: 2792-2803. Some of the data within this thesis also contributes in part to the following publications: Lidbury I, Johnson VR, Hall-Spencer JM, Munn CB, Cunliffe M (2012) Community-level response of coastal microbial biofilms to ocean acidification in a natural carbon dioxide vent system. Marine Pollution Bulletin, DOI:10.1016/j.marpolbul. 2012.02. 011, Suggett DJ, Hall-Spencer JM, Rodolfo-Metalpa R, Boatman TG, Payton R, Pettay T, Johnson VR, Warner ME, Lawson T (2012) Sea anemones may thrive in a high CO2 world. Global Change Biology. DOI: 10.1111/j.1365-2486.2012.02767.x
Temperature affects insect outbreak risk through tritrophic interactions mediated by plant secondary compounds

Global warming may affect population dynamics of herbivorous insects since the relative impact of bottom-up and top-down processes on herbivore survival is likely to be influenced by temperature. However, little is known about the mechanisms by which warming could affect regulation of populations, particularly when indirect effects across trophic levels are involved. We quantified larval survival of the needle-feeding European pine sawfly, Neodiprion sertifer, either protected from (caged) or exposed to natural enemies at three geographically separated localities in Sweden. The study shows that larval survival is affected by temperature but the direction of the effect is influenced by plant secondary compounds (diterpenes). The results suggest that survival of exposed larvae feeding on needles with high diterpene concentrations will decrease with increasing temperature, while larval survival on low diterpene concentration is less predictable with either no change or an increase with temperature. This food.
Antioxidant and anticancer capacity of saponin‐enriched Carica papaya leaf extracts

Summary The papaya (Carica papaya) leaf (PL) contains high levels of saponins and polyphenolic compounds, and historically, it has been used as a folk medicine for numerous ailments, including cancer. PL is traditionally prepared by hot water extraction; however, optimised extraction conditions have not been assessed. This study optimised conditions for the extraction of saponins from PL and assessed their antioxidant capacity and antipancreatic cancer activity. Optimisation was achieved using response surface methodology. Saponins and total phenolic compounds were assessed for their antioxidant, free radical scavenging, ion-reducing capacity, and antipancreatic cancer activity. Optimal aqueous extraction conditions were 85 °C, 25 min. and a water-to-leaf ratio of 20:1 mL g−1. Ethanol extracts demonstrated higher antioxidant, free radical scavenging and ion-reducing capacity, as well as antipancreatic cancer activity. This study revealed that the PL contains numerous bioactive compounds, with significant anticancer activity warranting further studies on the isolation and characterisation of individual bioactive compounds from the PL.