Spatial Scale

age of first breeding (Lo Valvo & Massa 2000). Focusing on the melitensis subspecies populations, a large decrease was observed through 1900', due to habitat degradation and introduction of predators, such as rats and cats (Massa 2006). For this reason a major attention should be paid to the Mediterranean subspecies. The second largest known population of storm pet-rels in the Mediterranean, located in Marettimo Island (It-aly) was first recorded by Krampitz (1956, 1957), who ob-served a few nests inside a pair of caves along the North-western coast. Krapp (1970) confirmed breeding in the caves recorded by Krampitz (1956, 1957) and also found some nests in the "grotta del Cammello", not cited by Krampitz. However, after subsequent visits by Massa and colleagues (Massa & Catalisano 1986, Lo Valvo & Massa 2000) smaller colonies apparently disappeared, probably due to the human disturbance or to a general decrease of the species. During later surveys, by 2007, some indivi...

Water management is one crucial component of agribusiness and municipal policy. One of the water-oriented dimensions is irrigation. In Pakistan, there is a lack of water system planning and water conservation management. This study is an effort to focus on water conservation and optimum crop yield using cost effective irrigation practices. This study is based on the comparative analysis among four irrigation techniques: flood irrigation (conventional), furrow, alternate furrow, and raised bed on wheat crop in order to decide the most efficient irrigation technique on clay loam soil. The wheat crop was cultivated in Rabi season from November 2015 to March 2018 on a one-acre area of a local farmer of Sajawal district, Sindh. Randomize complete block design (RCBD) method was used to design and allocate 3 irrigation sub-plots. The results show significance p

Abstraction of water from the dry river sand-beds is well-known as an alternative source of water during dry seasons. Internally, because of the form of sand particles, voids are created which can store water in the riverbeds. Large rivers are rare in South Africa. Many rivers are sand river types and without water during the prolonged dry periods. South Africa has not taken full advantage of water storage in sand as a solution to the growing water scarcity both in urban and rural areas. The paper reviews the benefits of run-off storage in sand reservoirs gained from other arid areas and need for adoption in rural areas of South Africa as an alternative water supply where it is probable.

Dytiscidae plays a vital role in the ecosystem; purifies water and serv es as the prey on many organisms. This family of aquatic beetles as predators feeds on small organisms. They are sensitive to environmental changes, it is used as a biodiversity indicator and also a tool for conservation assessment. This study assessed the diversity of Dytiscidae in relation to physico-chemical parameters of water using stratified random sampling at three Geogs in Dagana. Furthermore, the relationship of Dytiscid diversity and taxon richness with the physico-chemical parameters of the lentic and the lotic water bodies along the altitudinal gradient were determined and collected specimens. The total 664 individuals were collected in which five subfamilies of Dytiscidae, 12 genera and 17 species were identified. Pearson's correlation showed moderately negative correlation between the species diversity and taxon richness based on altitude and pH (p < 0.05). Temperature had moderate positive correlation with species diversity of Dytiscidae. Canonical correspondence analysis (CCA) showed temperature had an effective determining factor for distribution of Dytiscidae. Kruskal Wallis test among different habitats and altitudinal strata showed significant difference in Dytiscids diversity and taxon richness (p < 0.05). The diversity and richness showed a decreasing trend when the altitude increased. The highest diversity was found in marshy area (H = 2.36) and second altitude stratum (800-1200 masl) (H = 2.07) in the current study area. Therefore, the best conservation strategy of Dytiscidae could be to protect these areas before they are degraded.

MHD simulations of sunspots have successfully reproduced many aspects of sunspot fine structure as consequence of magneto convection in inclined magnetic field. We study how global sunspot properties and penumbral fine structure depend on the magnetic top boundary condition as well as on grid spacing. The overall radial extent of the penumbra is subject to the magnetic top boundary condition. All other aspects of sunspot structure and penumbral fine structure are resolved at an acceptable level starting from a grid resolution of 48 [24] km (horizontal [vertical]). We find that the amount of inverse polarity flux and the overall amount of overturning convective motions in the penumbra are robust with regard to both, resolution and boundary conditions. At photospheric levels Evershed flow channels are strongly magnetized. We discuss in detail the relation between velocity and magnetic field structure in the photosphere and point out observational consequences. Subject headings: MHD – ...

The multifaceted study of land-use changes and landscape history helps to understand the actual state of landscapes and habitats. The shore areas of Lake Balaton including the connected marshlands were significantly modified in the last 150 years. The traditional land use has almost completely disappeared from the southern shore areas; however the remnants of valuable wetlands are still represented. Our study area, the Balatonkeresztúri-rétek, is a highlighted nature conservation area and Natura 2000 site. Its land-use changes can represent the shifts of the whole marshland area of the southern shore. In our study the landscape history and the changes in land cover as an indicator of land use were followed up. The changes in land use were analyzed based on the surface covering data of historical maps and recent orthophotos using ArcGIS (ESRI) software. Each habitat of the study area was classified to the appropriate category of ÁNÉR (Hungarian General National Habitat Classification...

The size and shape of snow grains directly impacts the reflection by a snowpack. In this article, different approaches to retrieve the optical-equivalent snow grain size (ropt) or, alternatively, the specific surface area (SSA) using satellite, airborne, and ground-based observations are compared and used to evaluate ICON-ART (ICOsahedral Nonhydrostatic—Aerosols and Reactive Trace gases) simulations. The retrieval methods are based on optical measurements and rely on the ropt-dependent absorption of solar radiation in snow. The measurement data were taken during a three-week campaign that was conducted in the North of Greenland in March/April 2018, such that the retrieval methods and radiation measurements are affected by enhanced uncertainties under these low-Sun conditions. An adjusted airborne retrieval method is applied which uses the albedo at 1700 nm wavelength and combines an atmospheric and snow radiative transfer model to account for the direct-to-global fraction of the sol...

Se presenta una descripción cuantitativa de las comunidades intermareales asociadas a los litorales rocosos de Venezuela, la cual consideró las siguientes escalas espaciales jerárquicamente organizadas: regiones (separadas por cientos de kilómetros), localidades dentro de cada región (separadas por decenas de kilómetros), sitios dentro de las localidades (separadas por cientos de metros) y réplicas (separadas por metros). Se encontró que las comunidades de algas variaron significativamente a todas las escalas espaciales consideradas, mientras que los animales variaron significativamente sólo a las escalas espaciales de sitios y localidades pero no a la escala de regiones. Para las dos matrices de datos (algas y animales), los componentes de variación mayores estuvieron asociados a las escalas de localidades y réplicas, y los menores con la escala de regiones. Los resultados de este estudio tienen relevancia para el entendimiento de las comunidades asociadas a litorales rocosos tropi...

Distribution and abundance of two temperate-zone insectivorous bats, Daubenton's (Myotis daubentonii) and common pipistrelle (Pipistrellus pipistrellus), and their potential prey were studied along an altitudinal river gradient in relation to environmental variables including air temperature, wind speed, water surface state, and presence or absence of bank-side trees. Using a Latin square design at ten different habitat combination types, ultrasound recordings and insect sampling were carried out to quantify bat habitat preferences and potential prey abundance and classification. Myotis daubentonii and P. pipistrellus activity was significantly higher over smooth water river sections with trees on either or both banks while cluttered and rapid water sections were avoided. Conversely, insect abundance was not related to water surface condition or the presence or absence of bank-side trees. Nematoceran dipterans made up 98% of insect numbers, with small numbers of brachycerans and cyclorrhaphans. The most common insect families were Chironomidae and Ceratopogonidae. There was no correlation between bat activity and aerial insect activity, suggesting that aerial prey availability is not the sole driver of bat habitat choice. Bat and insect abundance were each correlated positively with night-time air temperature. No bat passes or flying insects were recorded at temperatures < 4°C. At 5°C, only M. daubentonii were observed foraging, and at 6ºC there were more M. daubentonii present than any other bat species. No correlation was found between number of bat passes hr-1 and wind speed, moon visibility, moon phase, and percentage cloud cover. Rain did not affect M. daubentonii, but P. pipistrellus preferred to forage on dry nights. Bats were predicted to forage preferentially where aerial insect abundance was highest but this was found to not be case, and other aspects such as detection of prey against clutter may have an important role to play in habitat choice.

Greater sage-grouse (Centrocercus urophasianus) populations have declined throughout the western United States over the past century. Loss of large stands of sagebrush is a major factor leading to the decline of sage-grouse populations. We captured, marked, and tracked hen sage-grouse in Wyoming during the summer of 2012 to study where sage-grouse hens keep their chicks given the dual needs to provide them with food and to keep them safe from avian predators. Vegetation surveys and avian point counts were performed at earlyseason brood locations, late-season brood locations, and random locations. We conducted multinomial models to determine which habitat variables were most informative in predicting site selection by hen sage-grouse. Hens with and without broods selected sites that had more shrub cover during the early-brood season but not during the late-brood season. During the early-brood season, hens without broods avoided sites where there were American kestrels (Falco sparveri...