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王蕙 《农业图书情报学刊》2007,19(8):175-178
为了加强对红树林生态环境保护的宣传力度,增强图书馆对外服务的功能,满足对红树林海岸生物多样性信息编目、分类等资料管理需求,采用目前先进的Web技术、数据库技术、数据处理技术构建了红树林海岸生物多样性信息管理系统,较为详细地讨论了构建专项库的意义以及关键技术。 相似文献
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沿海沙岸林果组合模式的建立──柑桔栽培 总被引:1,自引:0,他引:1
在沿海沙质岸段进行在林复合经营时,建立以柑桔为主的林果组合模式,可以提高沿海防护林经济效益,使防护林从生态型逐步向生态经济型方向发展。文中着重介绍了沙滩柑桔栽培技术。 相似文献
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The effects of two controlled release fertilizers, Forestcote 22-4-6 + Minors and Dry Site 21-6-2 + Minors, and also dolomitic lime, on growth and nutrition of bareroot Jeffrey pine (Pinus jeffreyi Grev. & Balf.) were investigated. Forestcote, which consists of loose prills, and Dry Site, consisting of prepackaged prills, were administered with two rates, while a single liming rate was used. An acidic Sierra Nevada surface mine provided the study site, and all amendments were applied at outplanting to the backfill of augered planting holes. Without impacting survival, both fertilizer formulations enhanced seedling growth, particularly at a 16 g rather than an 8 g application rate, although Forestcote was marginally more effective in this regard. In contrast, liming at a 27 g rate induced severe mortality and offset much of the growth gains resulting from fertilization. Improvements in N and P nutrition, as revealed by foliar analysis, probably accounted for much of the growth stimulation exhibited by fertilized seedlings, but reductions in the uptake of potentially phytotoxic trace elements such as Mn and Al and increases in base cation/metallic element ratios likely also contributed. The high application rate was generally preeminent in eliciting these nutritional responses. Liming induced little alteration of seedling nutrition. Impaired water relations may have caused the unfavorable responses to this treatment. 相似文献
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为有效地治理和改善矿区恶劣生态环境,使废弃的土地资源得以充分利用,通过对阜新海州露天矿土地复垦示范区土壤有机质、全N、有效P、速效K、EC、pH值、含水量、容重、紧实度等指标进行测定,开展了复垦土壤质量综合评价。结果表明:不同复垦示范区土壤质量差异较大,沙打旺、冰草示范区土壤质量最好;杨树、油松示范区次之;耕地、侧柏示范区土壤质量较差。 相似文献
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RENÉ FUNES-RODRÍGUEZ ALEJANDRO HINOJOSA-MEDINA GERARDO ACEVES-MEDINA SYLVIA P. A. JIMÉNEZ-ROSENBERG J. JESÚS BAUTISTA-ROMERO 《Fisheries Oceanography》2006,15(3):244-255
Seasonal assemblages of mesopelagic fish larvae and changes related with environmental factors (plankton biomass, sea surface temperature anomaly, upwelling, and the multivariate El Niño index) were investigated. From 1982 to 1987, 16 oceanographic cruises were carried out along the Pacific coast of Baja California Sur, Mexico. Larvae of 42 mesopelagic fish taxa were collected. Larval abundance was highly variable during the studied period, but summer months coincided with higher abundance (>200 larvae under 10 m2). Larval assemblages were dominated by three of the most common species of tropical (Vinciguerria lucetia, Diogenichthys laternatus) and subtropical affinity (Triphoturus mexicanus). A group of species of tropical affinity (Diplophos proximus, Diaphus pacificus, Benthosema panamense) was useful for distinguishing the 1982–84 El Niño event, and an assemblage of larvae of temperate affinity (Symbolophorus californiensis, Melamphaes lugubris, Bathylagus ochotensis, Leuroglossus stilbius, Protomyctophum crockeri) characterized ‘normal’ years (mid‐1984 to mid‐1987). 相似文献