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6972. Echolokace a hlasové projevy rejskovitých hmyzožravců. I. Orientace v prostoru a seismické vibrace
- Creator:
- Schneiderová, Irena
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biologické vědy, rejskovití, Soricidae, Česko, Czechia, orientace v prostoru, orientace v prostředí, echolokace, bělozubky, akustické monitorování, vnitrodruhová komunikace, dorozumívání zvířat, seismické vibrace, echolocation, Crocidurinae, 2, and 57/59
- Language:
- Czech
- Description:
- Rejskovití hmyzožravci (čeleď Soricidae) jsou drobní savci, kterých si v přírodě často sotva všimneme. Vyznačují se však mnoha zajímavostmi, díky kterým rozhodně stojí za naši pozornost. K těmto zajímavostem lze zařadit i schopnost echolokace, tj. schopnost orientovat se v prostoru za pomoci ozvěn cvakání, které vydávají. Kromě cvakání se během pohybu prostředím patrně orientují i pomocí štěbetavých hlasů. Bělozubky hnědé (Suncus murinus) při pohybu v neznámém prostředí také „duní“. Zda se i toto dunění uplatňuje při orientaci v prostoru není zatím jasné. Bělozubky pouštní (Diplomesodon pulchellum) zase při přechodu mezi různými typy substrátu vibrují, a tyto vibrace vytvářené celým tělem jim pravděpodobně pomáhají odhadnout vlastnosti substrátu a vyhnout se tak zbytečnému hrabání v hustém písku., Shrews (Soricidae) are small mammals that can be barely noticed in nature. However, there are many interesting facts that make them noteworthy, including echolocation - the ability to navigate with the help of echoes of the clicks they produce. Apart from the clicks, twitters are also probably used for navigation. The Asian House Shrew (Suncus murinus) moving through an unfamiliar environment produces boom, but it is not yet clear whether this sound is used for navigation. The Piebald Shrew (Diplomesodon pulchellum) produces body vibrations in response to a change in the substrate under their feet. These vibrations may be used for exploration of substrate density to avoid digging in dense sand., and Irena Schneiderová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6973. Echolokace a hlasové projevy rejskovitých hmyzožravců. II. Vnitrodruhová komunikace a ontogeneze hlasového repertoáru
- Creator:
- Schneiderová, Irena
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biologické vědy, rejskovití, hmyzožravci, ontogeneze živočichů, Soricidae, insectivores, animal ontogeny, 2, and 57/59
- Language:
- Czech
- Description:
- Rejskovití hmyzožravci (Soricidae) vydávají v nejrůznějších situacích mnoho typů hlasů. Dospělí jedinci se ozývají, pokud jsou v nebezpečí nebo se dostanou do potyčky s jiným jedincem svého druhu, během námluv a páření nebo při kontaktu s potomky. Také mláďata vydávají nejrůznější hlasy, jimiž se často snaží upozornit na své strádání nebo udržet kontakt s matkou a sourozenci. Přestože v poslední době přibývá publikací zabývajících se problematikou akustické komunikace rejskovitých, je to stále poměrně neprobádaná oblast. Mnohé otázky by mohly být zodpovězeny studiem bělozubky hnědé (Suncus murinus), která dobře prospívá i v péči člověka., Shrews (Soricidae) utter many types of vocalization in various situations. Adult individuals emit vocalizations when they are in danger or in a fight with conspecifics, during courtship and mating or when they keep contact with their offspring. Juveniles utter variable vocalizations mostly to prevent their discomfort and to keep contact with their mother and siblings. Although the number of publications has increased recently, acoustic communication among shrews still remains a quite unexplored field. Our knowledge might be significantly expanded by studying the Asian House Shrew (Suncus murinus), a species that can be successfully kept and bred in captivity., and Irena Schneiderová.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6974. Eckertův kalendář českého zemědělského školství pro posluchače a absolventy zemědělských ústavů a pro české rolnictvo na rok
- Publisher:
- Nákladem "Hosp. listu v Chrudimi"
- Format:
- print, text, regular print, bez média, svazek, and svazky : ilustrace, tabulky ; 24 cm
- Type:
- model:monograph and TEXT
- Subject:
- Zemědělství. Pedologie. Agrotechnika. Agroekologie, vzdělávání, školství, školy zemědělské, zemědělství, odborníci zemědělští, pracovníci zemědělští, Česko, 631, 377, 24, and UA01
- Language:
- Czech
- Description:
- K tisku upravil za přispění vynikajících odborníků Jan Eckert, odborný hospodářský učitel v Litomyšli a majitel "České Hospodyně" vycházející v Chrudimi
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6975. Eclipsing binaries - near and far
- Creator:
- Guinan, E. F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- binary stars and massive stars
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6976. Eco-hydrological impacts of Eucalyptus in the semi humid Ethiopian Highlands: the Lake Tana Plain
- Creator:
- Chanie, Tilashwork, Collick, Amy S., Adgo, Enyew, Johannes Lehmann, C., and Steenhuis, Tammo S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Eucalyptus, soil water repellency, Croton machrostachyus, and Koga watershed
- Language:
- Slovak
- Description:
- Eucalyptus is the tree of choice for wood production by farmers in Ethiopia. Although there are many claims about its harmful effect on ecology and water availability, little actual research exists. The main objective of this study was, therefore, to study the extent of harm of Eucalyptus on the ecosystem. This study was conducted at the Koga Watershed near Lake Tana in Ethiopia. Twenty-five farmers were interviewed and a field experiment with three replications was carried out to quantify the effect of Eucalyptus on various soil physical and chemical properties and maize crop measurements and to compare bulk density, soil moisture contents, maize crop counts and shading effects in fields bordered by Eucalyptus and Croton macrostachyus. Our results show that Eucalyptus decreased both soil nutrients and maize yields within 20 m of the trees. Although moisture content was not affected during the monsoon, it decreased faster within 30 m of the Eucalyptus trees than elsewhere. Soils become water repellent, too. Local farmers’ perception agreed with our experimental findings and indicated that Eucalyptus trees are exhausting the once productive land. They also reported that Eucalyptus dries up springs. Despite this, the growers insist on planting Eucalyptus because of its cash income.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6977. Eco-physiological modelling of leaf photosynthesis and adaptation analysis of Chinese ivy (Hedera nepalensis var. sinensis) in an evergreen broad-leaved forest in eastern China
- Creator:
- Yang, J., Cai, Y.-L., Sun, S.-C., and Wang, L.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- CO2 concentration, irradiance, simulation model, solar radiation, temperature, and vapour pressure dificit
- Language:
- Multiple languages
- Description:
- The individual plant of Chinese ivy can produce three types of branches (creepy, climbing, and reproductive) during its development, which adapt to different environmental factors. An eco-physiological model was constructed to simulate leaf net photosynthetic rate (PN) of Chinese ivy (Hedera nepalensis var. sinensis) in subtropical evergreen broad-leaved forest based on leaf physiological and mathematical analysis. The model integrated the rate-limiting biochemical process of photosynthesis and the processes of stomatal regulation. Influence of environmental factors (solar radiation, temperature, CO2 concentration, vapour pressure deficit, etc.) on PN was also considered in our model; its parameters were estimated for leaves on three types of branch in the whole growing season. The model was validated with field data. The model could simulate PN of leaf on three types of branches accurately. Influence of solar radiation on leaf PN of three types of branches in different seasons was analyzed through the model with numerical analysis. and J. Yang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6978. Ecological analyses of the intestinal helminth communities of the wolf, Canis lupus, in Spain
- Creator:
- Segovia, Juan-Matías, Guerrero, Ricardo, Torres, Jordi, Miquel, Jordi, and Feliu, Carlos
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- helminths, communities, Canis lupus, Spain (Werner, 1782), Toxascaris leonina (von Linstow, 1902), and Ancylostoma caninum (Ercolani, 1859) and Trichuris vulpis (Froelich)
- Language:
- English
- Description:
- This work describes the ecological characteristics of the intestinal helminth communities of 50 wolves (Canis lupus L.) from Spain. The species found were classified into three groups according to prevalence, intensity and intestinal distribution. Taenia hydatigena Pallas, 1766 and Uncinaria stenocephala (Railliet, 1884) are the core species of the community. Taenia multiceps (Leske, 1780) is a secondary species. The rest of the species, Alaria alata (Goeze, 1782), Taenia serialis (Gervais, 1847), Taenia pisiformis (Bloch, 1780), Dipylidium caninum (Linnaeus, 1758), Mesocestoides sp. aff. litteratus, Toxocara canis (Werner, 1782), Toxascaris leonina (von Linstow, 1902), Ancylostoma caninum (Ercolani, 1859) and Trichuris vulpis (Froelich, 1789), behave as satellite species. The linear intestinal distribution of all helminth species was analysed. The location of most species can be considered predictable, especially for core and secondary species. The analysis of interspecific relationships between infracommunities shows that negative associations are more numerous than positive associations. The role of A. caninum in the community is compared with that of U. stenocephala.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6979. Ecology or mythology? Are Whittaker’s “gradient analysis” curves reliable evidence of continuity in vegetation?
- Creator:
- Wilson , J. Bastow, Agnew , Andrew D. Q., and Sykes, Martin T.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- community ecology, environmental gradients, gradient analysis, species abundance, and Whittaker’s curves
- Language:
- English
- Description:
- Whittaker was one of the leading ecologists of his generation, introducing several ideas to plant community ecology. One approach involved deriving environmental-correlation curves in attempts to determine how the abundance of individual species changed along environmental gradients. These curves have been used extensively in the ecological literature of the last 50 years. However, there has been no examination of whether the methods used were sufficiently rigorous to justify Whittaker’s conclusions, let alone the very widespread use of them by others to draw general conclusions. Whittaker’s curves were based on large amounts of fieldwork. However, the sampling methods used were subjective, and the analyses of the data were often circular. When the curves are compared to the data on which they were based, it can be seen that many of the features that Whittaker claimed to see in his graphs are not supported. Whittaker’s main conclusions may have been correct but his studies do not stand up as pieces of scientific work.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6980. Economic analysis of scientific research publishing
- Creator:
- Šesták, Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- scientific research
- Language:
- Multiple languages
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public