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Long-Term Effects Of Tebuthiuron On Bromus Tectorum, Dana M. Blumenthal, Urszula Norton, Justin D. Derner, Jean D. Reeder

Western North American Naturalist

Use of herbicides to thin dense stands of Artemisia spp. (sagebrush) can free up resources for herbaceous plants and increase forage production, but may also facilitate weed invasion. We revisited a sagebrush thinning experiment in a north central Wyoming big sagebrush–grassland 11 years after application of tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N-N′-dimethylurea) to determine the long-term responses of shrubs, available soil resources, perennial grasses, and Bromus tectorum L. (downy brome). Tebuthiuron reduced shrub cover by more than half, from 31% in untreated plots to 15% in treated plots (P = 0.002), and increased downy brome cover approximately 4-fold, from 0.9% in untreated plots …

Evaluation Of Genetic Diversity Between Some Nitraria Retusa Populations Using Molecular Markers, Z. Abo El-Kheir, M. El-Monayeri, D. Abd El-Raof

Al-Azhar Bulletin of Science

Nitraria retusa (Nitrariaceae) is a true xerophyte plant grows in most deserts of Egypt, especially in wadies habitat and dry salt marshes. This study aims to evaluate any possible genetic diversity among samples of Nitraria retusa grown under different habitats using Random Amplified Polymorphic DNA (RAPD) markers, protein electrophoresis and isozyme electrophoresis. For such goal, the ecological aspects of the selected habitats were investigated with the view of finding correlations among these markers and some ecological parameters. Five collected samples of Nitraria retusa were collected from Wadi Hof (sunny and shady), Oyun Musa, Kattamyia and Hammam Faraon. The obtained results …

Prevalensi Dan Determinan Hipertensi Di Pulau Jawa, Tahun 2004, Zamhir Setiawan

Kesmas

Hipertensi merupakan faktor risiko utama kardiovaskuler yang merupakan penyebab utama kematian di seluruh dunia. Peningkatan umur harapan hidup dan perubahan gaya hidup meningkatkan faktor risiko hipertensi di berbagai negara. Tujuan penelitian ini (1) Mengetahui prevalensi hipertensi dan penyebarannya di Pulau Jawa tahun 2004. (2) Mengetahui faktor-faktor sosiodemografi yang berhubungan dengan kejadian hipertensi. (3) Mengetahui kontribusi dan dampak potensial masing masing faktor tersebut. Penelitian dengan rancangan studi Ekologi Multilevel ini menggabungkan variabel tingkat pengukuran individu dengan tingkat pengukuran ekologi dalam analisis bersama, dengan unit analisis individu. Analisis kontekstual dilakukan melalui kerangka konsep hipertensi, menggunakan metode analisis regresi logistik ganda, dengan status …

Champions Of Change: Reinventing Democracy Through Land Law Reform, John R. Nolon

Pace Environmental Law Review

No abstract provided.

Plant Composition And Erosion Potential Of A Grazed Wetland In The Salmon River Subbasin, Idaho, Kristine N. Hopfensperger, Joan Q. Wu, Richard A. Gill

Western North American Naturalist

Wetlands are dynamic habitats with many unique, important functions including filtering sediments and providing diverse habitats for fish and wildlife. Wetlands in the western United States are particularly important because they offer habitat for a number of protected runs of endangered fish species. Historically, livestock grazing has altered wetland and riparian area form and function by facilitating exotic species invasions, altering spatial heterogeneity of vegetation, and increasing erosion. In this study we examined vegetation structure and erosion potential in a wetland meadow exposed to unregulated grazing along Deer Creek in the Salmon River subbasin, Idaho. We characterized the vegetation composition …

Ecophysiological Studies On Some Species Growing Along Wadi El-Natrun El-Alamein Desert Road, Safaa Ismaeil, Zeinab Khidr, Aesha Abd El-Kawy

Al-Azhar Bulletin of Science

The present study was carried out to elucidate the adaptive responses of some desert plants growing in two different habitats along Wadi El-Natrun El-Alamein Desert Road. The species characterizing the sand- gravel plain habitat include Thymelaea hirsuta, Artemisia monosperma, Deverra tortuosa and Traganum nudatum, while those characterizing the dry saline habitat are Zygophyllum album and Asphodelus microcarpus. The species of dry saline habitat attained higher values of water content, degree of succulence, calcium, magnesium and chlorides. Also, Zygophyllum album achieved the highest ash content and this was mainly due to accumulation of Na+, Ca+2 and Mg+2. In addition, Na+ were …

Survey And Population Studies On Coleopterous Fauna Of Northern Sinai And Beni–Suif Governorates Using Light Traps, G. Morsi, A. El–Gharbawy

Al-Azhar Bulletin of Science

A survey together with studies on population densities and relative abundance of coleopterous species were conducted by the use of light traps at Al–Arish city, North Sinai and Sids Agricultural Research Station, Beba City, Beni Suif during 2005. At Beni–Suif the survey revealed the presence of 45 coleopterous species belonging to 31 genera of 9 families: Anobiidae, Bostrychidae, Carabidae, Cicindelidae, Dytiscidae, Elateridae, Hydrophilidae, Scarabaeidae and Staphylinidae. While surveying Northern–Sinai revealed the presence of 64 coleopterous species belong to 44 genera of 10 families: Anobiidae, Bostrychidae, Carabidae, Cerambycidae, Dytiscidae, Elateridae, Hydrophilidae, Paussidae, Scarabaeidae and Staphylinidae. The total annual number of beetles …

Preliminary Survey Of Terrestrial Vertebrate Fauna And People’S Awareness Towards Wildlife In The Northern Governorate Of The Gaza Strip, Maged Yassin, Abdel Fattah Abd Rabou, Mohammad Al-Agha

Al-Azhar Bulletin of Science

Many plant and animal species have disappeared in the Gaza Strip during the last 5-6 decades. No effort has been made to stop such disappearance and/or to conserve the biodiversity. This survey deals with the terrestrial vertebrate fauna in the Northern Governorate of the Gaza Strip. The ecological awareness of people (n=75) towards wildlife was investigated using a questionnaire specially designed for this purpose. A total number of 119 terrestrial, wild vertebrate species (13 mammals, 86 birds and 20 reptiles), in addition to many localy extinct mammalian species were recorded. Many wildlife species are on their way to extinction where …

The Effect Of Livestock Grazing On The Rainbow Grasshopper: Population Differences And Ecological Correlates, Sandra J. Debano

Western North American Naturalist

This study examined the effect of livestock grazing on a common herbivore in semiarid grasslands of the Southwest: the rainbow grasshopper, Dactylotum variegatum. Population attributes and key environmental variables were compared between sites on active cattle ranches and sites on a 3160-ha ungrazed sanctuary. Although density of D. variegatum nymphs did not differ significantly between grazed and ungrazed sites, adult density was significantly lower on grazed sites, and sex ratios differed between grazed and ungrazed sites over time. Grazed sites had higher percentages of bare ground and fewer Baccharis pteronioides, a common shrub. However, only bare ground was …

Tamarix Aphylla: A Newly Invasive Tree In Southern Nevada, Lawrence R. Walker, Pamela L. Barnes, Elizabeth A. Powell

Western North American Naturalist

In the southwestern United States, the nonnative athel pine (Tamarix aphylla) was presumed to be sterile and therefore not as likely to spread as its widely distributed, nonnative congener, T. ramosissima. However, at Lake Mead National Recreation Area (LMNRA) in southern Nevada, populations of T. aphylla have recently spread beyond their limited pre-1990 distribution and now form extensive monospecific stands. Over a 3-year period, we quantified seed production and germination from 60 T. aphylla trees at LMNRA. The annual mean seed production period was 50.6 days, and the mean potential germination (under laboratory conditions) was 22%, indicating …

Characteristics Of Swift Fox Dens In Northwest Texas, Brady K. Mcgee, Kerry L. Nicholson, Warren B. Ballard, Matthew J. Butler

Western North American Naturalist

The swift fox (Vulpes velox) was classified in 1995 as a candidate for listing under the Endangered Species Act. Since then, several studies have addressed survey methods for monitoring swift fox populations. The purpose of this paper is to assist field researchers in documenting the presence of swift foxes by identification of recently active den sites. We propose that swift foxes have unique external den characteristics that can be distinguished during aerial surveys. We collected data from 30 swift fox den complexes on both continuous rangeland and landscapes fragmented by cropland in northwest Texas. There were no differences …

Behavioral Genetics And Crime, In Context, Owen D. Jones

Law and Contemporary Problems

Jones explains the relationship between behavioral genetics and other disciplines in behavioral biology. He compares the potential contributions of behavioral genetics and behavioral ecology and suggests how the diverging efforts could be joined. He also notes that criminal law is but one of many fields of law potentially affected by behavioral genetics.

Dietary Overlap In Giant Salamanders (Dicamptodon): Applying Null Models To Resource Partitioning, Craig A. Steele, Colin Brammer

Western North American Naturalist

We examined stomach contents of preserved specimens of larval Pacific giant salamander (Dicamptodon tenebrosus) and Cope's giant salamander (D. copei) collected from sympatric and allopatric stream populations. The dietary components of these specimens were used to calculate dietary overlap between the 2 species and to determine if changes in overlap existed between sympatric and allopatric populations. To statistically test overlap values, a randomization algorithm was used to construct a simulated data matrix (i.e., null model) in order to compare observed values of dietary overlap to a distribution of overlap values from the null model. Significant levels …

Aspects Of Sacramento Pikeminnow Biology In Nearshore Habitats Of The Sacramento–San Joaquin Delta, California, Matthew L. Nobriga, Frederick Feyrer, Randall D. Baxter

Western North American Naturalist

We documented distribution, relative abundance, diet composition, and body condition of Sacramento pikeminnow Ptychocheilus grandis during 2001 and 2003 at 5 sites in the Sacramento–San Joaquin Delta, California. Sacramento pikeminnow densities in nearshore habitats were higher in 2003 than 2001. In both years, spatial distribution of beach seine densities was similar. There were no significant differences in density among sampling sites except for the southernmost site where the catch was near zero. Based on rotary screw-trap data from a 6th site, we found relative abundance of Sacramento pikeminnow entering the Delta via an artificial floodplain was positively correlated with flow. …

Long-Term Fire History In Great Basin Sagebrush Reconstructed From Macroscopic Charcoal In Spring Sediments, Newark Valley, Nevada, Scott Mensing, Stephanie Livingston, Pat Barker

Western North American Naturalist

We use macroscopic charcoal analysis to reconstruct fire history in sagebrush (Artemisia tridentata var. wyomingensis and A. tridentata var. tridentata), in Newark Valley, Nevada. We analyzed charcoal at continuous 1-cm intervals (~7–127 years), and pollen at 2- to 10-cm intervals (~70–263 years) in a core spanning the last 5500 cal yr BP (calendar years before present). A charcoal peak in the historic period was associated with a >1400-ha fire dated to 1986 that burned in the watershed. We reconstructed the prehistoric fire history by inferring fires from similar charcoal peaks that were significantly greater than the background charcoal …

Estimating Spatial Curve Number For Hydrologic Response Analysis Of A Small Watershed

Journal of Spatial Hydrology

An approach to estimate the curve number (CN) at each pixel unit of a satellite imagery, which is a key parameter in the widely used Soil Conservation Service Curve Number (SCS- CN) hydrologic model, is proposed. Instead of mapping land use and its temporal dynamics from satellite imageries, this approach linearly unmixes the multi-spectral radiances into three fractional layers which primarily control the degree of saturation within a watershed occurring due to a 25 cm-depth storm event, i.e., physically interpreted as the CN. The fraction layers used are water, sand and pure vegetation. In order to obtain a relationship between …

Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball

Aliso: A Journal of Systematic and Floristic Botany

Species of duckweeds (Letnnaceae) that were resolved as sister taxa in a phylogeny based on combined molecular and non-molecular data were compared for morphological, physiological, and ecological attributes to infer factors important in the initial divergence leading to speciation. The ability to survive extreme conditions such as desiccation and cold temperatures is the most common difference identified between species. Two morphological characters facilitating survival in extreme environments are production of special resting buds called turions and increased seed production. The prevalent geographic pattern for species pairs consists of one restricted species occurring on the periphery of a more widespread taxon; …

Further Evidence For Seed Size Variation In The Genus Zostera: Exploratory Studies With Z. Japonica And Z. Asiatica, Sandy Wyllie-Echeverria, Victoria R. Wyllie-Echeverria, Algernon C. Churchill, Paul A. Cox

Aliso: A Journal of Systematic and Floristic Botany

Recent studies found seed size variation within the seagrass Zostera marina, one of nine species in the genus Zostera. The objectives of this study were to determine if variation also exists in the seeds of two other species Zostera japonica and Zostera asiatica within this genus. Results indicate that: (1) length and weight varied between two populations (one indigenous population from Akkeshi-Ko, Japan, and one exotic population from Willapa Bay, Washington, USA) of the small-bodied intertidal seagrass species Z. japonica, and (2) seed-size classes were discernable. Preliminary investigations were also initiated with a Japanese population of Z. asiatica …

Emerging Policy Issues On Non-Timber Forest Products In Nepal, Ranu Shrestha-Acharya, Joel Heinen

HIMALAYA, the Journal of the Association for Nepal and Himalayan Studies

No abstract provided.

Editorial 1: Unpacking The Complexity Of The Homonym Site/Sight/Cite, Jan Jagodzinski

Journal of Social Theory in Art Education

We invite essays that explore visual regimes that have become established in our public schools or art departments. "Out of sight" might interrogate current ideals, territories, and debates concerning visual cultural education, since this was a distant horizon first discussed in JSTAE in 1980 and is now looming closer in mainstream art education. "Out of sight" might provide us with concerns over our televised, cinematic images that come at us through popular culture. For Lacan, sight was always a form of misrecognition, a form of "ignorance" as brilliantly explored by Magritte. We are all framed by images. So, we invite …

Archaeological Testing For The Walker Ranch Park Bridge Project (41bx1271), San Antonio, Bexar County, Texas, Barbara A. Meissner

Index of Texas Archaeology: Open Access Gray Literature from the Lone Star State

In April 2006 the Center for Archaeological Research (CAR) of the University of Texas at San Antonio was contracted by the Parks and Recreation Department of the City of San Antonio to perform subsurface investigations within the boundaries of site 41BX1251, in north-central San Antonio, Bexar County, Texas. The purpose of the testing was to learn if the concrete abutment of a planned pedestrian bridge over Salado Creek would impact significant archaeological deposits in this site, which is a part of the Walker Ranch National Historic District.

Five shovel tests and one backhoe trench were excavated. The shovel tests were …

Feeding Habits Of Common Snook, Centropomus Undecimalis, In Charlotte Harbor, Florida, David A. Blewett, Rebecca A. Hensley, Philip W. Stevens

Gulf and Caribbean Research

We examined the feeding habits, ontogenetic and seasonal diet variations, and predator size–prey size relationships of common snook, Centropomus undecimalis, in Charlotte Harbor, Florida, through stomach contents analysis. A total of 694 stomachs were extracted from common snook (300–882 mm standard length [SL]) during a 24-month period (March 2000–February 2002); 432 stomachs contained prey items. At least 37 prey taxa were identified, including 19 that had not been previously reported. Fishes made up 71% of the prey by number and 90% by weight. Three prey items made up almost 50% of the diet numerically—Lagodon rhomboides, Anchoa spp., …

How Do Aesthetics Affect Our Ecology?, Zsuzsi I. Kovacs, Carri J. Leroy, Dylan G. Fischer, Sandra Lubarsky, William Burke

Journal of Ecological Anthropology

Beauty is a powerful force that affects both our emotions and our ecological practices, yet aesthetic values remain understated and under-discussed in ecology. Here we invite discussion about the influence of beauty on ecological research by outlining: 1) how aesthetics affect the practice of ecology, and 2) how aesthetics affect the implementation of ecological research on the landscape. The aesthetic sensibilities of ecologists develop through personal experiences and are enriched by professional training, including ecological coursework, fieldwork, research and discussion. Many ecologists choose an ecological career because it offers an opportunity to work in beautiful, natural places. However, these values …

Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart

Journal of the Iowa Academy of Science: JIAS

Macroinvertebrate and fish habitat is often degraded as a result of agriculture. Riparian buffer strips are commonly used to counteract the negative effects of agriculture in headwater streams. We assessed the relation of multi-aged riparian buffer strips to in-stream habitat, macroinvertebrate and fish assemblages in an Iowa stream. In-stream habitat, macroinvertebrates, and fish were sampled from two buffered sites and two unbuffered sites, with the greatest substrate, water depth, and velocity heterogeneity occurring in buffered sites. The highest macroinvertebrate richness (11) as well as fish species richness (14), diversity (1.99) and IBI score (37) were found in the site buffered …

Relation Of Riparian Buffer Strips To In-Stream Habitat, Macroinvertebrates And Fish In A Small Iowa Stream, Jeremy P. Duehr, Michael J. Siepker, Clay L. Pierce, Thomas M. Isenhart

Journal of the Iowa Academy of Science: JIAS

Macroinvertebrate and fish habitat is often degraded as a result of agriculture. Riparian buffer strips are commonly used to counteract the negative effects of agriculture in headwater streams. We assessed the relation of multi-aged riparian buffer strips to in-stream habitat, macroinvertebrate and fish assemblages in an Iowa stream. In-stream habitat, macroinvertebrates, and fish were sampled from two buffered sites and two unbuffered sites, with the greatest substrate, water depth, and velocity heterogeneity occurring in buffered sites. The highest macroinvertebrate richness (11) as well as fish species richness (14), diversity (1.99) and IBI score (3 7) were found in the site …

Salt Ingestion Caves, Charles A. Lundquist, William W. Varnedoe Jr.

International Journal of Speleology

Large vertebrate herbivores, when they find a salt-bearing layer of rock, say in a cliff face, can produce sizable voids where, over generations, they have removed and consumed salty rock. The cavities formed by this natural animal process constitute a unique class of caves that can be called salt ingestion caves. Several examples of such caves are described in various publications. An example in Mississippi U.S.A., Rock House Cave, was visited by the authors in 2000. It seems to have been formed by deer or bison. Perhaps the most spectacular example is Kitum Cave in Kenya. This cave has been …

Apple Snail Densities In Habitats Used By Foraging Snail Kites, Philip C. Darby, Robert E. Bennetts, Laksiri B. Karunaratne

Florida Field Naturalist

No abstract provided.