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981.
Robin S. Vora 《西北部美国博物学家》2011,48(1)
Surface-bearing pressure in newer logging skid trails compared to the 40+ -year-old trails was approximately 60% greater as measured by a cone penetrometer. Surface soil compaction from tractor skidding may last 40 years or more, as evidenced by the fact that skid trails of that age were 20% more resistant to the penetrometer than areas adjacent to trails. No relationship was found between dry-bulk density (measured with a balloon apparatus) and surface-bearing pressure. 相似文献
982.
Leucism in the western bluebird ( Sialia mexicana ) is reported from La Plata County, Colorado. 相似文献
983.
Stephen L. Wood 《西北部美国博物学家》2011,35(1)
New replacement names for junior homonyms are presented as follows; Acanthotomicus tuberculifer for A. (Mimips) tuberculatus Schedl 1967, Chactoptelius versicolor for C. (Acrantus) tricolor Schedl 1958, Hylesinopsis angolanus for H. (Aridiamerus) angolensis Schedl 1982, Hylurgops tuberculifer for H. tuberculatus Schedl 1947, Pseudothysanoes spinatifer for P. spinatus Wood 1956, Scolytodes aterrimus for S. ater (Hylocurosoma atrum Eggers) 1941, Scolytodes boliviensis for S. (Prionosceles) bolivianus Eggers 1928, Scolytodes brasiliensis for S. (Hexacolus) brasiliensis Schedl 1935, Scolytodes discriminatus for S. discedens Eggers 1943, Scolytodes elongatissimus for S. elongatus (Hylocurosoma elongatum Eggers) 1943, Scolytodes gennaens for S. genialis Wood 1978, Scolytodes laevigatulus for S. (Hexacolus) laevigatus Schedl 1962, Scolytodes laevicorpus for S. laevis (Hylocurosoma laeve Eggers) 1943, Scolytodes majus for S. major Eggers 1943, Scolytodes medialis for S. medius Eggers 1943. New synonymy is reported for Dactylipalpus niger Schedl (= D. unctus Wood), Dendroctonus armandi Tsai & Li (= D. prosorovi Kurenzov & Kononov), Sinophloeus porter Brèthes (= S. destructor Eggers). Species new to science include: Acacicis bicornis (New Guinea), Acacicis zeylanicus (Sri Lanka), Sphaerotrypes bengalensis (India), Sphaerotrypes costatus (North Andaman Island), Sphaerotrypes cristatus (Sri Lanka), Sphaerotrypes pentacme (Burma), Sphaerotrypes ranasinghei (Sri Lanka), Xylechinus ougeiniac (India), Xylechinus padus (India). 相似文献
984.
Dorothy E. Beetle 《西北部美国博物学家》2011,49(4)
Wyoming lacks a rich molluscan fauna due to its considerable elevation, extremes of temperature, the short period between killing frosts, scanty, moisture, and intermittent creeks. Recent mollusks found in the state total 42 genera (109 species), including 6 genera (23 species) of bivalves, 15 genera (42 species) of freshwater gastropods, and 21 genera (44 species) of land gastropods. Synonymy, the counties in which each species was collected, and habitat notes are given. 相似文献
985.
Mourning doves ( Zenaida macroura ) in a cold-desert ecosystem used man-made ponds for watering, feeding, gritting, loafing, and courting. Diurnal pond use by doves peaked in the morning and evening. Monthly dove use of ponds fluctuated slightly during the summers of 1984 and 1985. Pond size, pH, and shoreline characteristics had little association with the intensity of pond use by doves; but geographic isolation of ponds was weakly associated with pond-use intensity. The number of doves present at the beginning of the one-hour period was a poor indicator of the number of arrivals during that period. We conclude that man-made water sources are important in areas where water availability may limit mourning dove productivity and abundance. It is suggested that mourning dove arrival rates could be used as a population index in cold-desert areas. 相似文献
986.
Studies in several areas in Arizona and New Mexico show that dwarf mistletoe ( Arceuthobium douglasii ) is rare in young Douglas-firs growing under infected overstories. Less than 5% of the Douglas-firs under 26 years old and less than 6% of those under 1.4m tall were infected in 77 mistletoe-infested stands. Both percent infection and mean dwarf mistletoe rating of young Douglas-firs increased as tree age, height, and stand dwarf mistletoe ratings increased. 相似文献
987.
Proper quadrat and sample sizes for sampling species frequency vary among vegetation types. This study found 10 × 10-cm quadrats most appropriate for frequency sampling dry mountain meadows when using a single quadrat size. If large, broad-leaved forbs are of special interest, 25 × 25-cm, 25 × 50-cm, or 50 × 50-cm quadrats may be useful. One hundred 10 × 10-cm quadrats adequately sampled most common species at alpha = 0.20 ± 10% frequency. In contrast, more than five hundred 0.29-m 2 circular plots usually were needed to sample individual species yield at alpha = 0.20 ± 20% of the mean. 相似文献
988.
Wilmer W. Tanner 《西北部美国博物学家》2011,41(1)
This third report on the herpetofauna of Chihuahua deals exclusively with amphibians. The first plethodonid salamander is reported, species Ambystoma rosaceum is discussed in greater detail than before, and two subspecies are recognized. Spea is elevated from subgeneric to generic rank, and S. stagnalis Cope is removed from synonymy and is recognized as a subspecies of hammondii . The species listed include the following: 2 salamanders and 19 anurans (1 Scaphiopus , 2 Spea , 9 Bufo , 1 Eleutherodactylus , 2 Hyla , 3 Rana , and 1 Microhyla ). Reference is made to vaious habitats that are associated with elevations arising form lower deserts and extending into the western mountains. The role played by the dry and wet annual cycles is also noted. 相似文献
989.
Marguerite E. Voorhees 《西北部美国博物学家》2011,50(1)
At peak standing crop, rillscale ( Atriplex suckleyi ) foliage grown on amended bentonite mine spoil contained adequate digestible energy, crude protein, and all mineral elements except phosphorus necessary for cattle, sheep, antelope, and deer. Amendments (sawdust, NPK, gypsum) generally did not affect forage quality. Iron, manganese, aluminum, sodium, and potassium concentrations were high and may have adversely affected forage quality. Forage utility would be limited to a few months during the growing season. 相似文献
990.
Louis A. Somma 《西北部美国博物学家》2011,47(3)
Clutch sizes of the prairie skink, Eumeces septentrionalis , in Nebraska are positively correlated with female snout-vent lengths (SVLs). Data presented in this study and others indicate Nebraska populations of E. septentrionalis have larger average clutch sizes than other populations within this species' range. 相似文献