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11.
世界粮食研究模型在黑龙江省作物产量预报中的应用 总被引:6,自引:5,他引:6
在现有研究成果的基础上,提出世界粮食研究(WOFOST)模型在黑龙江省四大作物产量预报应用中的参数分区处理方法,运用WOFOST的模拟产量和趋势产量对黑龙江省四大作物产量进行了预测分析。研究表明:该方法效果理想、可行,具有理论研究和实际应用价值,克服了只用一组参数在复杂气候区域进行作物产量模拟的局限性,拓宽了WOFOST模型在复杂气候条件下的应用领域。 相似文献
12.
The idea that landscape has been created by human activities on a biophysical basis allows for clear cause–effect reasoning.
However, landscape planning and management practice learns that it is impossible to neglect the social perception of landscape,
i.e. the ways people think about nature and landscape. It is the result of social research and human sciences of the last
decade that a differentiation in views of nature and landscape can be identified in the different groups of social actors
in the landscape. Case studies from France and the Netherlands show a marked change in values attributed to nature and landscape
in the end of the last century. Social demand for landscape is growing and a shift from a functional image of nature and landscape
to a more hedonistic image like the Arcadian and wilderness images has taken place. Comparing the Netherlands with France
and rural with urban inhabitants, the influence of urbanisation is evident in this process. It is further shown that images
of nature vary considerably between for example farmers, urban residents, hunters and conservationists. The way people perceive
landscape seems determined by their functional ties with the landscape and the social praxis in which they encounter the landscape.
It is concluded that the concept of landscape is nearer to the lifeworld of people than the abstract notions of nature and
biodiversity. This implies a big challenge both for national and international landscape policies and for local landscape
management initiatives to be developed, taking into due consideration both the material and immaterial nature of landscape. 相似文献
13.
Buijs S Van Poucke E Van Dongen S Lens L Tuyttens FA 《Journal of animal science》2012,90(10):3568-3573
We studied the effect of increased cage size on different aspects of bone quality (bone strength, diameter, weight, and length) and fluctuating asymmetry (FA). Such characteristics may indicate improved animal welfare, as greater bone quality may decrease fracture incidence during handling, whereas decreased FA has been suggested to signal decreased stress. As stress is likely not only influenced by the quantity of space, but also by its quality, we also studied the effect of environmental enrichment. Groups of 8 rabbits were housed in wire open-top cages of 0.40, 0.46, 0.53, 0.64, 0.80, 1.07, and 1.60 m(2) from weaning until slaughter. All cages of 0.40 and 0.46 m(2) (12 cages/size) were left barren to allow sufficient mobility. One-half of the larger cages were enriched with a wooden-enrichment structure that could be used to gnaw on, hide in, or lie in (6 cages per size × enrichment treatment). Increased cage size led to an increase in tibiofibula diameter (P = 0.008), a tendency for increased tibiofibula weight (P = 0.051), and decreased FA (P = 0.010), suggesting improved welfare. Bone length and strength were not affected by cage size (P > 0.1). Enrichment did not affect FA (P > 0.1), in contrast with our expectations based on previous glucocorticoid analysis. This discrepancy between indicators may be due to sensitivity to other types of stressors or different sensitive periods. In summary, rabbits housed in larger cages had wider, heavier bones, but the absence of changes in bone strength indicate that this is unlikely to result in decreased fracture incidence. In larger cages, FA was lower, suggesting a favorable effect on welfare, whereas no effect of enrichment was shown. 相似文献
14.
David K Meyerholz Yannick E Vanloubbeeck Shannon J Hostetter Dianna M Jordan Amanda J Fales-Williams 《Journal of veterinary diagnostic investigation》2005,17(3):295-298
The purpose of this study was to characterize the incidence and diagnostic features of amyloidosis and other diseases found at necropsy in captive trumpeter swans (Cygnus buccinator). A search of Iowa State University's Department of Veterinary Pathology and Veterinary Diagnostic Laboratory databases yielded 31 trumpeter swan (C. buccinator) necropsy cases from captive swans in protected habitats. Eleven of the 31 birds had amyloid deposition most commonly in the spleen (8 of 11), liver (7 of 11), and kidney (6 of 11) and less often in the pancreas (2 of 11) and adrenal gland (2 of 11). Amyloid deposition effaced normal tissue with adjacent necrosis and hemorrhage in severe cases. Amyloidosis was most often diagnosed in February and March. Other disease diagnoses in the trumpeter swans included aspergillosis (5 of 31, 16%); bacterial infection (5 of 31, 16%); lead toxicosis (3 of 31, 10%); gout (2 of 31, 6%); parasitic infection (2 of 31, 6%); vitamin E deficiency (1 of 31, 3%); trauma (1 of 31, 3%); and ventricular foreign body (1 of 31, 3%). Histopathologic, toxicologic, and microbiologic analyses did not define an etiologic diagnosis in the deaths of 9 trumpeter swans. In these cases, necropsy lesions included emaciation (5 of 9), enteritis (1 of 9), pulmonary hemorrhage (1 of 9), and no lesions (3 of 9). The number of trumpeter swan case submissions was greatest in January and February. This study provides a reference for veterinary diagnosticians concerning incidence and diagnostic features of amyloidosis and other diseases in captive trumpeter swans of the midwestern United States. 相似文献
15.
Yannick D.N. Tremblay Skander Hathroubi Mario Jacques 《Canadian journal of veterinary research》2014,78(2):110-116
Bacterial biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that is attached to a surface. Biofilms protect and allow bacteria to survive and thrive in hostile environments. Bacteria within biofilms can withstand host immune responses, and are much less susceptible to antibiotics and disinfectants when compared to their planktonic counterparts. The ability to form biofilms is now considered an attribute of many microorganisms. Diseases associated with biofilms require novel methods for their prevention, diagnosis and treatment; this is largely due to the properties of biofilms. Furthermore, the presence of biofilms on surfaces found at farms, slaughterhouses or food processing plants will have an impact on the efficacy of disinfection protocols. Surprisingly, biofilm formation by bacterial pathogens of veterinary or zoonotic importance has received relatively little attention. The objective of this brief Review article is to bring awareness about the importance of biofilms to animal health stakeholders.(Translated by the authors) 相似文献
16.
This study investigates the impact of landscape heterogeneity on community structure and population dynamics in two families of Diptera (Empididae and Chironomidae). Adult emergence is compared with aerial flow by means of emergence traps and yellow traps on a transect across four habitats (pond banks, woodland, grassland and heathland) in close proximity to each other. Empids use different space units according to their larval development, sexual behaviour and food requirements. This creates an intermingling of species and individuals originating from different habitats in the lowest part of the transect. Adult chironomids of aquatic species exhibit a preferential use of open habitats while adults with terrestrial larvae disperse largely above the four sites. Habitat fragmentation and heterogeneity lead to opposite patterns in chironomid distribution: some species disperse over the whole set of macrohabitats but others are confined to a single patch, resulting in population isolation. The impact of spatial and temporal landscape patterning is discussed with a view to community structure, life-history tactics and population dynamics. 相似文献
17.
N Stockhofe-Zurwieden R M Buijs M De Jong 《DTW. Deutsche tier?rztliche Wochenschrift》2001,108(6):267-269
Four pigs, each of about 8 weeks of age were submitted for pathological examination because of severe cachexia, combined with an enormous distension of the abdomen. In the herd, where these pigs originated from, these clinical signs were observed frequently for some period of time and stricture of the rectum was suspected. All pigs showed a severe cachexia, and most prominent in all pigs was a megacolon with large and distended colon and caecum and stenosis about 30 to 60 cm cranial of the anus. Tissue specimens were taken from the rectum, from the colon cranial and caudal of the stenosis and from the jejunum and examined histologically. Ganglia in the intestinal wall were examined immunohistochemically by using antibodies recognising neurofilament protein (kD 200). In all pigs submucosal and myenteric ganglia were absent in the post stenotic colon and rectum and in transverse section of the stenosis, whereas in the prestenotic colon of all pigs and also in the jejunum ganglia were present. Segmental aganglionosis of the colon is also known in humans (Hirschsprung disease) and other animal species and is considered as a congenital disorder. We also suggest a familiar background of the disease in these pigs. 相似文献
18.
Jacques M Aragon V Tremblay YD 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2010,11(2):97-121
Bacterial biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that is attached to a surface. Biofilms protect and allow bacteria to survive and thrive in hostile environments. Bacteria within biofilms can withstand host immune responses, and are much less susceptible to antibiotics and disinfectants when compared with their planktonic counterparts. The ability to form biofilms is now considered a universal attribute of micro-organisms. Diseases associated with biofilms require novel methods for their prevention, diagnosis and treatment; this is largely due to the properties of biofilms. Surprisingly, biofilm formation by bacterial pathogens of veterinary importance has received relatively little attention. Here, we review the current knowledge of bacterial biofilms as well as studies performed on animal pathogens. 相似文献
19.
Yannick Joye Kim Willems Malaika Brengman Kathleen Wolf 《Urban Forestry & Urban Greening》2010,9(1):57-64
Over the last three decades solid empirical evidence for the positive influence of greenery on human psychological and cognitive functioning has been steadily accruing. Based on this evidence, researchers and practitioners increasingly realize the importance of urban greening as a strategic activity to promote human wellbeing. Although commercial and retail activities constitute a significant and influential component of urban contexts, a concern is that the stakeholders involved (e.g. merchants) can sometimes be reluctant to integrate vegetation in commercial districts. This can be an important stumbling block for the process of urban greening. In this paper we introduce the concept of Biophilic Store Design (BSD) as the retail design strategy to consciously tap the beneficial effects of vegetation. The central aim of this paper is to demonstrate that the reluctance of certain retail stakeholders to integrate greening practices like BSD is unjustified. Two lines of evidence in support of this claim will be discussed. On the one hand, we sketch a conceptual framework which supports the view that BSD can have restorative effects for those implied in store environments. On the other hand, we review Wolf's multi-study research program on the effects of urban greening on consumer behavior, attitudes, and perceptions. These two lines of evidence show that commercial activities and urban greening are not to be considered as antagonistic but as mutually reinforcing practices. 相似文献
20.
People from all ethnic backgrounds spend some of their leisure time in green areas. This study found that urban parks are more inclusive green places than non-urban green areas, and that urban parks can promote social cohesion. The objective of the research was to establish the extent to which urban parks facilitate social cohesion and how social interaction and place attachment can contribute to such cohesion. Quantitative research (a survey) and qualitative research (observations and interviews) carried out in five urban parks in the Netherlands revealed that there are many similarities in the ways that ethnic groups use urban parks and in the meanings of such parks to these groups. Urban parks are sites where different ethnic groups mingle and where informal and cursory interactions can stimulate social cohesion. Furthermore, being involved and concerned with parks can facilitate attachment to these places. Urban parks can provide a vital locality where everyday experiences are shared and negotiated with a variety of people. The design of a park, its location and people's image of the park in combination with the cultural characteristics of various ethnic groups inform the opportunities for intercultural interactions. 相似文献