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31.
2009年更加严格的针对木材进口的全球贸易规则正在美国和其他国家实行，该规则将可能会影响境外木材的供应。至于新的法律和规则究竟会在多大程度上千扰地板市场仍然不是很清楚。一些业内人士认为国外树种的时代一去不复返，而其他人则认为国外树种依旧是市场的主角。 相似文献
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Marie-Hélène Lizée Stéphanie Manel Jean-Fran?ois Mauffrey Thierry Tatoni Magali Deschamps-Cottin 《Landscape Ecology》2012,27(2):159-169
The aim of this paper is to examine the role of urban public parks in maintaining connectivity and butterfly assemblages.
Using a regression framework, we first test the relative importance of park size and isolation in predicting abundance and
species richness of butterfly assemblages across a set of 24 public parks within a large metropolitan area, Marseille (South-East
France). Then, we focus on landscape features that affect diversity patterns of the recorded butterfly communities. In this
second part, the urban landscape surrounding each park is described (within a 1 × 1 km window) according to two major components:
vegetated areas (habitat patches) and impervious or built areas (matrix patches). Specifically, we aim to test whether the
incorporation of this built component (matrix) in the landscape analysis provides new insights into the understanding of ecological
connectivity in the urban environment. We found a significant effect of both matrix configuration (shape complexity of the
built patches) and distance from regional species pool (park isolation) on diversity of butterflies that overrides park size
in their contribution to variation in species richness. This result suggests that many previous studies of interactions between
biodiversity and urban landscape have overlooked the influence of the built elements. 相似文献
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国会已经通过了具有里程碑意义的两党立法,禁止进口非法采伐木材和木材产品。众议院和参议院已经以压倒总统否决权的绝对优势通过了抗击非法木材采伐法案（The Combat Illegal Logging Act）,严禁可能的黑市木材产品交易活动。 相似文献
36.
Crystal N. Johnson Sue Barnes John Ogle D. Jay Grimes Yun-Juan Chang Aaron D. Peacock Liz Kline 《Journal of the World Aquaculture Society》2008,39(2):251-258
In closed recirculating systems, a particulate matter consisting of bacteria, algae, fungi, and detritus develops spontaneously. This microbial floc can serve as a high‐protein food source for finfish and shellfish and has the potential to supplement the protein required in shrimp feed. To advance the use of microbial floc as a feed supplement, it is necessary to manipulate its microbial components, which requires thorough characterization of the bacterial components. Pacific white shrimp, Litopenaeus vannamei, were raised in a closed recirculating system, and water was compared to the contents of shrimp foreguts and hindguts. Water consistently contained less microbial biomass than did shrimp guts, but 16S rDNA sequences indicated that water was more diverse than shrimp guts. Phylogenetic analysis of 16S rDNA sequences retrieved from water and shrimp foregut grouped these sequences into various unrelated generic clusters. Fatty acid analysis demonstrated that shrimp feed was not a major contributor of microbial fatty acids to shrimp tanks, as the feed mostly contained polyunsaturated fatty acids, which are typically found only in eukaryotes. It is hoped that elucidating more details about the various components of microbial floc will help in understanding its development and will lead to its use as a high‐protein feed supplement. 相似文献
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Liz Copas R. R. Williams Gillian M. Arnold 《The Journal of Horticultural Science and Biotechnology》2013,88(4):455-458
SummaryPaclobutrazol was applied, with or without mefluidide, to the grassed alleyways between the bare soil tree lines in a bush cider orchard cv Michelin. The chemical not only suppressed grass growth but, in the year following application, produced typical paclobutrazol effects on the trees in adjacent rows including a reduction in growth. 相似文献
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Liz Ota John Herbohn Steve Harrison Nestor Gregorio Vera Lex Engel 《Agroforestry Systems》2018,92(6):1597-1609
Systematic mapping studies provide a snapshot of the literature based on systematic literature searches. In this systematic mapping study, the original research that links reforestation and livelihoods in the tropics was mapped and analysed to identify the trends, biases and gaps in the literature. In total, 339 papers from 92 journals were identified. Agroforestry Systems was the journal in which articles were most frequently published, and Cameroon and Indonesia the most frequently studied countries. The greatest number of authors came from the USA, and authors were most commonly affiliated with ICRAF. A limited collaboration between research groups in the tropical regions was identified. Anthropology and Social Sciences were the most frequent areas of research, especially in Africa. Latin America had more technical studies and more publications discussing payment for environmental services than the other regions. Based on the temporal analysis of the main terms in abstracts of the publications included, it was found that agriculture-related terms and terms related to the human component in the landscape were consistently prevalent in the literature relating reforestation and livelihoods throughout time. Agroforestry systems were especially important in small-scale reforestation and livelihoods. Trends, biases and gaps were discussed. Broader cooperation between tropical regions and between clusters of authors would be beneficial for research and practice. 相似文献
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The agricultural/livestock system of a 40,000 km2 area in western Sudan is described. Details of the three main components—traditional rainfed agriculture, small-scale irrigation and animal husbandry—are given. Data on crop yields and livestock production at both the unit level and the system level are provided. Millet is the main cereal crop overall but sorghum occupies an important place in the intensively cultivated alluvial zones. Cash crops, including groundnuts, chillies and okra for drying, are of some importance. Onions are the main winter irrigated crop while mangoes and citrus are important tree crops. The livestock sector is dominated by cattle which account for more than 75% of the livestock units present. Gross output of the area at 1976 prices was calculated at £Sud 14·8 to £Sud 16·2 million (US$ 41·4 to US$ 45·4 million) equivalent to £Sud 41·7 to £Sud 45·6 per head of population and £Sud 3·70 to £Sud 4·05 per hectare. Of these totals between 33 and 36% could be attributed to livestock production. 相似文献
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Cytologic appearance of a keloidal fibrosarcoma in a dog 总被引：1，自引：1，他引：0
Little LK Goldschmidt M 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2007,36(4):364-367
A 5-year-old neutered male, mixed-breed dog was presented with a single 4-mm, nodular, firm, haired subcutaneous mass on the left flank that had been present for approximately 2 weeks. Cytologic preparations of the mass revealed many spindle cells, few mast cells, rare eosinophils, rare macrophages, abundant hyalinized collagen, and moderate numbers of erythrocytes. The spindle cells were oval to fusiform, with oval nuclei, finely stippled to lacy chromatin, 1-5 variably sized prominent nucleoli, and moderate to abundant cytoplasm with indistinct cell borders, wispy cytoplasmic extensions, and occasionally, fine magenta granulation. The cell population exhibited moderate anisocytosis, moderate anisokaryosis, and rare binucleation. The eosinophilic material occurred both in large angular aggregates with blunt ends and in amorphous aggregates with fine wispy projections. Histologic findings were consistent with a keloidal fibrosarcoma. To the authors' knowledge, this report is the first to describe the cytomorphologic characteristics of a keloidal fibrosarcoma in a dog. 相似文献