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941.
In this paper we report the results of a study on the suitability of the dehesa (Mediterranean woodlands) as habitat of red deer (Cervus elaphus hispanicus) in a closed country estate of about 4300 ha total surface situated in the San Pedro Mountain, in Central Extremadura, Spain. We have described the deer management with respect to habitat, exploitation mode, deer feeding, population control and production of goods and services. It is concluded that the dehesa system is a rich natural resource that preserves and improves the degraded environment.
Abbreviations CS collected surface - DMFCU deedmixed feed cattle units - Fi final inventory - FS fertilized surface - Ii Initial inventory - K Potassium - N Nitrogen - NBF number of breeding females - NBFIi number of breeding females of initial inventory - NBFR number of breeding females released - NBM number of breeding males - NBMIi number of breeding males of initial inventory - NBMR number of breeding males released - NCCR number of captive calves released - NCFi number of calves of final inventory - NCR number of calves released - NFR number of female renovation - NYMR number of young males released - NYFR number of young females released - P phosphorus - PP permanent Pastures - pts pesetas - QS Quercus stalks - RDED resources directly eaten by deer - SPOM selected hunted down poor quality males - SS sowed surface - TN total needs of deer - TNR total number released - UAS useable agrarian surface - WB wooded brush - WQS wooded Quercus surface - WS wooded surface 相似文献
Resumen En el presente trabajo se estudia la dehesa como hábitat del ciervo (Cervus elaphus hispanicus). Se ha tomado como referencia una finca cerrada de 4300 ha de ST situada en la Sierra de San Pedro, en Extremadura, España. Se describen los sistemas de gestión actuales del ciervo en cuanto a hábitat, modo de explotación, alimentación, control de población y producción de bienes y servicios. Concluyendo con la necesidad de fomentar este tipo de explotaciones cinegéticas de dehesa que ayudan a conservar y potenciar el medio ambiente en zonas despobladas y deprimidas
Abbreviations CS collected surface - DMFCU deedmixed feed cattle units - Fi final inventory - FS fertilized surface - Ii Initial inventory - K Potassium - N Nitrogen - NBF number of breeding females - NBFIi number of breeding females of initial inventory - NBFR number of breeding females released - NBM number of breeding males - NBMIi number of breeding males of initial inventory - NBMR number of breeding males released - NCCR number of captive calves released - NCFi number of calves of final inventory - NCR number of calves released - NFR number of female renovation - NYMR number of young males released - NYFR number of young females released - P phosphorus - PP permanent Pastures - pts pesetas - QS Quercus stalks - RDED resources directly eaten by deer - SPOM selected hunted down poor quality males - SS sowed surface - TN total needs of deer - TNR total number released - UAS useable agrarian surface - WB wooded brush - WQS wooded Quercus surface - WS wooded surface 相似文献
942.
943.
采用非稳态法测定龙竹竹材热压干燥过程中的水分扩散系数,并探讨了温度对水分扩散系数的影响.结果表明:干燥温度越高,干燥各阶段水分扩散系数及平均水分扩散系数也越大;初始高含水率阶段,随含水率逐渐降低,水分扩散系数呈逐步增加趋势,在纤维饱和点附近时达最大值;随后,随含水率逐渐降低呈逐步减少趋势. 相似文献
944.
945.
946.
Kenji Ono Motohiro Hasegawa Makoto Araki Masahiro Amari Masakazu Hiraide 《Journal of Forest Research》2007,12(4):255-261
We examined the relationships between the absorptional characteristics in the near infrared region and the chemical changes
of decomposing beech (Fagus crenata) and pine (Pinus densiflora) litters. Spectra as well as the concentrations of chemical substances approached each other and converged with decomposition,
although both initial characteristics differed markedly between beech and pine. This indicated that the fundamental chemical
structures were almost the same, although their organochemical composition differed. Specific absorption bands for lignin,
polysaccharide, and protein were identified at 2,140 and 1,670 nm, 2,270, 1,720, 1,590, and 1,216 nm, and 2,350 nm, respectively.
Absorbance at 1,670 nm, peculiar band of aromatics, showed a positive correlation with lignin concentration, which suggested
the relative increment of aromatics due to condensed lignin in decomposing litters. Absorbance at 2,140 nm, characterized
as the C–H bond in HRC = CHR, showed a negative correlation with lignin concentration, which suggested the decrements of some
structures such as side-chains in lignin polymers unrelated to aromatics. Absorbance at 2,270, 1,720, and 1,216 nm, specified
to O–H/C–O/C–H bonds in saccharide, might reflect the change of polysaccharide during decomposition because they showed a
positive correlation to polysaccharide concentration. In the same way, absorbance at 2,350 nm, identified to the C–H/CH2 bonds in protein, showed a negative correlation to nitrogen concentration in decomposing litters, which might indicate that
the C–H/CH2 bonds in protein decreased with decomposition due to microbial consumption of carbon in protein. Our findings suggested the
possibility that the spectral changes indicate the litter digestibility during decomposition and that also explain the compositional
change in decomposing litters. 相似文献
947.
948.
经测定 ,落叶松腮扁叶蜂蛹在自然条件下发育起点温度为 8.3 85 6℃± 0 .5 5 0 2℃ ;有效积温为 1 0 2 .5 41 9± 2 6.5 2 2 9日度。 相似文献
949.
介绍了新西兰生产的高防潮中密度纤维板的性能,特点,产品的一般使用技术要点,以及在家具及室内装修方面的应用技术。 相似文献
950.
在全面调查普洱市七叶莲野生资源地理分布基础上,采用主成分分析法研究七叶莲野生资源地理分布与气候、地形之间的关系,并对海拔与七叶莲枝叶总皂甙含量做相关性分析。调查结果表明:七叶莲野生资源在普洱全市均有分布,在喀斯特地貌区域分布尤为集中,其水平分布范围为99°20′11″E~101°55′04″E,22°18′20″N~24°17′58″N,垂直分布范围为海拔500~1900 m。经主成分分析表明,影响七叶莲地理分布的主要水热指标的排序为湿度因子>热量因子>降水因子;相关分析结果表明,七叶莲所分布的海拔与其林木枝叶总皂甙的含量具负相关关系,其相关系数为-0.948,最高海拔(1460 m)与最低海拔(1006 m)的七叶莲枝叶总皂甙含量比为1.0∶1.5。 相似文献