scholarly journals Seed Preferences in Sparrow Species of the Monte Desert, Argentina: Implications for Seed-Granivore Interactions

The Auk ◽  
2006 ◽  
Vol 123 (2) ◽  
pp. 358-367 ◽  
Author(s):  
Víctor R. Cueto ◽  
Luis Marone ◽  
Javier Lopez de Casenave
Keyword(s):  
Soil Seed Bank ◽  
Necessary Condition ◽  
Toxic Compounds ◽  
Monte Desert ◽  
Zonotrichia Capensis ◽  
Seed Preference ◽  
Negative Effect ◽  
Bird Diet ◽  
Feeding Pressure ◽  
Sporobolus Cryptandrus

Abstract We assessed seed preference in four species of sparrows that are common to the central Monte desert of Argentina. Our hypotheses are that (1) sparrows always prefer grass over forb seeds and (2) different species of sparrows show the same preferences when consuming seeds. We presented seeds from eight species of plants (four grasses and four forbs) in both choice and nonchoice experiments. In general, sparrow species preferred grass over forb seeds, though one of them (Rufous-collared Sparrow [Zonotrichia capensis]) included one forb species (Parthenium hysterophorus) among its preferred seed items. Among grass seeds, sparrows avoided or showed less preference for the tiny seeds of Sporobolus cryptandrus, which suggests that seed weight may affect seed choice among grasses. Avoidance of most forb species, by contrast, could not be associated with seed size, probably because of the presence of unpalatable or toxic compounds in forb seeds. Experimental evidence suggests that the main feeding pressure of sparrows is clearly directed to grass seeds, which coincides with reported information on bird diet. Results support assertions that sparrows can cause a negative effect on the composition and abundance of grass seeds in the soil seed-bank, a necessary condition for birds in playing a significant role on grass population dynamics in the central Monte desert of Argentina. Preferencias por Semillas de los Emberízidos del Desierto del Monte, Argentina: Implicancias para la Interacción Semillas-granívoros

Impact of Zygogramma bicolorata on vegetative and reproductive performance of Parthenium hysterophorus in Nepal

2021 ◽  
Vol 27 (02) ◽  
pp. 2296-2306
Author(s):  
A. S. R. Bajracharya ◽  
◽  
R. B. Thapa ◽  
G. B. KC ◽  
S. B. Pradhan ◽  
...  
Keyword(s):  
Reproductive Performance ◽  
Soil Seed Bank ◽  
Control Agent ◽  
Parthenium Hysterophorus ◽  
Shoot Biomass ◽  
Potential Candidate ◽  
Zygogramma Bicolorata ◽  
Negative Effect ◽  
Noxious Weed ◽  
Parthenium Weed

Parthenium hysterophorus Linn. is one of the most aggressive, invasive weeds threatening natural and agricultural ecosystems in Nepal. Leaf feeding beetle, Zygogramma bicolorata Pallister (Coleoptera: Chrysomelidae), is regarded as a potential candidate for biological control of Parthenium weed. Considering the fact effectiveness of Z. bicolorata against P. hysterophorus was evaluted in Nepal. Z. bicolorata caused 98.25 % defoliation of P. hysterophorus reducing 38.88 % plant height, 27.29 % plant width, 26.25 % root length, 12.33 % leaves, 40.58 % shoot biomass and 36.59 % root biomass in the period of 90 days. The flower production and soil seed bank were reduced by 50.22 % and 40.29 %, respectively. Z. bicolorata was an efficient bio-control agent with a significant negative effect on the vegetative and reproductive performance of the noxious weed P. hysterophorus.

ADAPTOGENIC EFFECT OF APISIL AND TOS-BIO PREPARATIONS ON A HONEY BEE UNDER CONDITIONS OF HYPERTHERMIA

2021 ◽  
Vol 0 (4) ◽  
pp. 63-68
Author(s):  
E.S. SALTYKOVA ◽  
◽  
N.M. ISHMURATOVA ◽  
L.R. GAIFULLINA ◽  
A.V. POSKRYAKOV ◽  
...  
Keyword(s):  
Survival Rate ◽  
Honey Bee ◽  
High Temperatures ◽  
Biochemical Parameters ◽  
The Body ◽  
Necessary Condition ◽  
The Family ◽  
Negative Effect ◽  
Adaptogenic Effect ◽  
Time Changes

The temperature factor has a huge impact on bees and their development. In a complex complex of adaptation, not only a perfect system of collective thermoregulation of the family is important, but also such individual adaptations as resistance to freezing and tolerance to high temperatures. The deviation of the ambient temperature from the optimal one increases the energy consumption of bees for the regulation of the microclimate in the family. This means that it enhances metabolic processes, which affects the state of the body and the life expectancy of insects. In addition, sometimes the use of high temperatures is a necessary condition for their maintenance, for example, in the fight against the parasite of the bee mite varroa. At the same time, the effect of high temperatures can have a negative effect not only on the mite, but also on the bees. In laboratory conditions, the effect of Apisil and TOS-BIO preparations containing 9-oxoand 10-hydroxy-2E-decenoic acids as a base - the most important components of the «queen substance» and royal jelly of the honey bee Apis mellifera L., respectively - on the survival rate and biochemical parameters was studied. adult worker bees exposed to extremely high (50oC) temperatures. The dynamics of the activity of phenoloxidase and catalase as biochemical indicators of the stress response of a honey bee under high temperature load has been studied. It was shown that the insects' resistance to hyperthermia increased with the content of these preparations in the feed. Experimental results indicate that under extreme (50oC) temperature conditions Apisil and TOS-BIO preparations have an adaptogenic effect on worker bees, increasing their resistance to hyperthermia. At the same time, changes in the initial level and dynamics of biochemical parameters indicate that these compositions in the most economical way contribute to the restructuring of metabolism in the mode of optimal functioning, which affects the level of changes in enzyme activity (with less pronounced changes in activity). and also on the survival rate of bees at the end of the experiment.

Soil seed bank composition over desert microhabitats: patterns and plausible mechanisms

2004 ◽  
Vol 82 (12) ◽  
pp. 1809-1816 ◽  
Author(s):  
Luis Marone ◽  
Víctor R Cueto ◽  
Fernando A Milesi ◽  
Javier Lopez de Casenave
Keyword(s):  
Seed Production ◽  
Seed Bank ◽  
Soil Seed Bank ◽  
Bare Soil ◽  
Seed Density ◽  
Seed Composition ◽  
Monte Desert ◽  
Total Seed ◽  
Seed Dynamics ◽  
Primary Dispersal

We assessed soil seed bank composition and size over several microhabitats of two habitats of the central Monte Desert of Argentina (open Prosopis woodland and Larrea shrubland) to analyse differences among them. Seed densities were similar to those already reported for other deserts, but we found consistent differences in seed composition among microhabitats. Whereas grass seeds (e.g., Aristida, Pappophorum, Neobouteloua, Trichloris, Digitaria) prevailed in natural depressions of open areas, forb seeds (e.g., Phacelia, Lappula, Descurainia, Plantago, Chenopodium) were more abundant under trees. The comparison of seed production during primary dispersal (i.e., seed rain) with seed density on the ground at the end of dispersal indicated that most forb seeds entered the habitat through the micro habitats located beneath the canopy of trees and tall shrubs, and remained there after redistribution. Most grass seeds, by contrast, entered it through bare-soil and under-grass microhabitats, and reached more even distributions after secondary dispersal, especially because of dramatic losses in bare soil. Patterns of plant recruitment and seed dynamics in specific microhabitats were better understood when differences of soil seed bank composition, but not of total seed density, were taken into account.Key words: Monte Desert, seed dispersal, seed predation, seed production, seeds.

scholarly journals Configurations of Essential Factors Promoting China’s Commercial Health Insurance: A Qualitative Comparative Analysis Based on Technology-Organization-Environment Framework

2021 ◽  
Author(s):  
Xiuquan Huang ◽  
Xiaocang Xu ◽  
Tao Zhang
Keyword(s):  
Health Insurance ◽  
Comparative Analysis ◽  
High Performance ◽  
Social Insurance ◽  
Qualitative Comparative Analysis ◽  
Robustness Analysis ◽  
Necessary Condition ◽  
Key Factors ◽  
Negative Effect ◽  
Commercial Health Insurance

Abstract Background With the improvement in the living standards, China’s health insurance under the social security system cannot satisfy people's diversified and high-level demands. Therefore, it is necessary to promote commercial health insurance (CHI). This study identifies driving paths of CHI in China from configuration perspective. Methods This study innovatively constructs an analysis framework based on the Technology-Organization-Environment theory to investigate the driving path of China's commercial health insurance. Using the data of 31 provincial regions of China in 2018, the fuzzy-set Qualitative Comparative Analysis (QCA) is employed for configuration analysis. For the robustness analysis of necessary condition, we also adopt the Necessary Condition Analysis. Results Three main findings are discovered. First, there is no necessary relationship between any condition and high or not-high performance of CHI and any condition. Nevertheless, there are three sufficient configurations, TOE strategy, GA-EA-CD strategy, and dual EA-CD strategy, to achieve high performance, and another three, TMC-EA-CD strategy, TI-EA strategy, and TI-TMC-EA strategy, to reach not-high performance. Second, technological conditions (TI and TMC) and EA are relatively more important than other conditions. Third, it is confirmed that the financial expenditure of government departments has a negative effect on the development of commercial health insurance. Conclusion There are configurations or pathways to achieve high or not-high performance of promoting CHI and key factors are identified successfully. Each region should choose the driving path suitable for itself, instead of making homogenization policies and replicating policies of regions with high performance. Besides, TC and EA as key factors should be overcome. Finally, the governments should formulate policies to systematically evaluate social insurance and CHI simultaneously and promote their coordinated development.

TO THE QUESTION OF USING INDUSTRIAL TOBACCO WASTES FOR INCREASING SOIL FERTILITY

2019 ◽  
Keyword(s):  
Soil Fertility ◽  
Degradation Rate ◽  
Soil Surface ◽  
Pathogenic Fungi ◽  
Carbon Dioxide Production ◽  
Current Interest ◽  
Toxic Compounds ◽  
Safe Method ◽  
Negative Effect ◽  
Nitrogen Phosphorus

Irretrievable industrial tobacco wastes – tobacco dust is buried at special areas or undergoes combus-tion process; therefore it is serious pollution agent. Because of this methods for its non-burying recycling are of current interest. For example, tobacco dust can be used for increasing soil fertility, as it contains nutritious compounds: nitrogen (1.84-2.3%), phosphorus (0.24-0.37%) and potassium (2.14-3.72%). But there is information that tobacco dust undergoes little degradation in the soil during one season and after second applying it can lead to soil intoxication and to dying of its microorganisms. Thus, efficient method for solving this problem is searching techniques for decreasing toxicity of dust applied into soil as ferti-lizer. New ecologically safe method for recycling tobacco dust is proposed. It is based on utilizing tobac-co dust (2, 5, 8 t/ha) in combination with biodestructors (Sternifag 80g/ha or Biocomplex BTU 1l/ha). For increasing degradation rate onto non-toxic compounds biodestructor is applied in combination with water and ammonium nitrate on dust uniformly spread soil surface. After that this mixture should be ploughed one month before sowing or transplanting. Utilizing this method allows increasing basic labile nutrients (nitrogen, phosphorus, potassium) in the soil and its biological activity, which is seen by in-creasing nitrification properties, intensity of cellulose destruction, carbon dioxide production. Also this method allows soil improving because of pathogenic fungi suppression, decreasing negative effect on en-vironment and partially solve problem of safe recycling industrial tobacco wastes.

Seed germination and longevity of autumn-flowering and autumn-seed producing Mediterranean geophytes

2012 ◽  
Vol 22 (4) ◽  
pp. 299-309 ◽  
Author(s):  
I. Marques ◽  
D. Draper
Keyword(s):  
Seed Germination ◽  
Mediterranean Climate ◽  
Soil Seed Bank ◽  
Natural Conditions ◽  
Rainy Period ◽  
Urginea Maritima ◽  
Negative Effect ◽  
Autumn Flowering ◽  
In Fire ◽  
Scilla Autumnalis

AbstractThe seasonality of the Mediterranean climate has important implications for plant physiology and some specific conditions must be met before germination can occur. Most plants sprout during the spring season although a few germinate during the autumnal rainy period. To understand the patterns of germination under autumn conditions we selected five Mediterranean autumn-flowering geophytes that usually co-exist in fire-prone habitats:Leucojum autumnale,Narcissus cavanillesii, Narcissus serotinus, Scilla autumnalisandUrginea maritima. Experiments were performed under conditions simulating those prevailing in the habitat during the autumnal Mediterranean season when seeds of these species usually germinate. In all species, germination occurred quickly ( < 7 d), was usually higher at the lowest temperatures tested (15°C, 20°C; >89%) and no signs of delayed germination were detected. Nevertheless, species usually had different patterns of seed germination, a strategy that might avoid interspecific competition when co-occurring in the same habitats. Germination was lower and slower in light than in darkness, suggesting that under natural conditions germination of seeds directly exposed to sunlight can be severely restricted. Several fire-dependent treatments (heat and ash) revealed a lack of fire-stimulated germination, and treatments even had a negative effect. In addition, only a small fraction of seeds remained viable after 1 year of dry lab storage and their germinability was very low, suggesting the absence of a permanent soil seed bank in the life cycle of these geophyes.

scholarly journals RISK FACTOR: THEORY AND PRACTICE IN THE APPLICATION IN EPIDEMIOLOGICAL STUDIES

2017 ◽  
Vol 22 (6) ◽  
pp. 306-310
Author(s):  
Evgeny D. Savilov ◽  
S. N Shugaeva
Keyword(s):  
Risk Factors ◽  
Risk Factor ◽  
General Pattern ◽  
Epidemiological Studies ◽  
Theory And Practice ◽  
Epidemiological Surveillance ◽  
Necessary Condition ◽  
Risk Marker ◽  
Negative Effect ◽  
Correct Application

The category “risk factor” is widely used in the clinical epidemiological studies. To date, a large number of applied studies on the specific characteristics of risk factors for individual nosological forms has been published. At the same time, there is a minimum of publications concerning dealing with a general pattern concerning the theoretical basis for the application of this epidemiological category. In connection with this, the purpose of this report is the theoretical presentation and justification for the use in the epidemiological studies of the category “risk factor”. The authors give an epidemiological definition to this term. The risk factor is any property or feature of the human population, any impact on it, which increases the probability of a negative effect on the incidence and/or its consequences on the prevalence of any epidemiological phenomenon. The article considers the main variants of grouping risk factors and their detailing by various classification criteria (external and internal factors, managed and unmanaged factors). The need to study the complex impact of risk factors, especially in combination and/or comorbidity diseases, is shown. The authors gave an epidemiological interpretation of the risk-related concepts: “risk determinant” and “risk marker”, the areas of correct application of these terms in clinical epidemiological studies are indicated. A proposal was made to use the term “determinant of risk” only in those cases when the investigated factor has a high degree of evidence of causality with the event being studied and is not disputed by other specialists. Examples of the substitution of the concepts “risk factor” and “risk marker” are given. There is marked the situation in which clinical and epidemiological studies mask real risk factors. In conclusion, the authors indicate to the evident level of designation and identification of risk factors as a necessary condition for the success of anti-epidemic measures and the adoption of adequate management decisions in the epidemiological surveillance system.

scholarly journals Ecology and Genetics of Cyperus fuscus in Central Europe—A Model for Ephemeral Wetland Plant Research and Conservation

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1277
Author(s):  
Pavel Kúr ◽  
Soňa Píšová ◽  
Karin Tremetsberger ◽  
Pavel Dřevojan ◽  
Zygmunt Kącki ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Central Europe ◽  
Soil Seed Bank ◽  
Suitable Model ◽  
Vegetation Diversity ◽  
Ephemeral Wetland ◽  
Recent Climate ◽  
Threatened Taxa ◽  
Negative Effect ◽  
Riverine Habitats

The ecology and species diversity of ephemeral wetland vegetation have been fairly well studied, but the biology of its characteristic species has rarely been investigated holistically. Here we combine previous results on the genetic diversity of a suitable model species (the diploid Cyperus fuscus) with new data on its historical and recent occurrence, its ecological and climatic niche, and the associated vegetation. Analysis of phytosociological relevés from Central Europe revealed a broad ecological niche of C. fuscus with an optimum in the Isoëto-Nanojuncetea class, extending to several other vegetation types. Overall species composition in the relevés highlight C. fuscus as a potential indicator of habitat conditions suitable for a range of other threatened taxa. Analysis of historical records of C. fuscus from the Czech Republic showed an increasing trend in the number of localities since the 1990s. It seems that recent climate warming allows the thermophilous C. fuscus to expand its range into colder regions. Isoëto-Nanojuncetea and Bidentetea species are well represented in the soil seed bank in both riverine and anthropogenic habitats of C. fuscus. Vegetation diversity has a weak negative effect and anthropogenic (compared to riverine) habitats have a strong negative effect on genetic diversity in this species.

Impact of heat on seed germination of three perennial grasses in the semiarid region in Central Argentina

2016 ◽  
Vol 64 (5) ◽  
pp. 451 ◽  
Author(s):  
Alicia G. Kin ◽  
Carla E. Suárez ◽  
Claudia C. Chirino ◽  
Patricia L. Ávila ◽  
Ernesto F. A. Morici
Keyword(s):  
Heat Shock ◽  
Seed Germination ◽  
Seed Bank ◽  
Soil Seed Bank ◽  
Seed Viability ◽  
High Heat ◽  
Perennial Grasses ◽  
Semiarid Region ◽  
Central Argentina ◽  
Negative Effect

Fire is an important factor affecting the viability and germination of seeds in the soil seed bank. We evaluated the effects of heat on germination and seed viability of three native perennials winter grasses of central Argentina. Seeds of two palatable grasses Piptochaetium napostaense (Speg.) Hack, Nassella tenuis (Phil.) Barkworth and a non-palatable Jarava ichu Ruiz & Pav. were exposed to different heat shock treatments resulting from a combination of temperature: 70, 90, 120, 140 and 170°C and three exposure times (5, 10 or 20 min) and a control (no heat) treatment. All control treatments had a high percentage of seed viability (>97%). Germination of P. napostaense was not affected by mild heat shock (70 and 90°C) but it was sensitive to higher temperatures: no seeds survived the exposure to 140 and 170°C. Seeds of this species have awns that facilitate the burring of seeds in the soil, which can reduce fire exposure. N. tenuis and J. ichu were less sensitive to heat. High heat shock reduced seed germination but not seed viability. These experiments show that seeds of P. napostaense, the target species for management on these grasslands, were the most sensitive to heat treatments. Our results show that heat shock can have a negative effect on the soil seed bank of P. napostaense (palatable and dominant species), but does not have significant effects on J. ichu seeds (unpalatable species). Thus, we suggest that the current management recommendations for the use of controlled fire to promote palatable species may not be optimal for these species.

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