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101.
The research was conducted in selected 80- to 110-year-old spruce stands in the south-eastern part of the Českomoravská Upland
at altitudes from 350 m a.s.l. to 465 m a.s.l. The regional standard tree-ring chronology shows very low increments for years
1974, 1976 and 1992. After 1992, there is a sharp rise in increments with a climax in 1997. Afterwards, increments gradually
decrease, reaching minima in 2003 and 2008. The years with low increments were also confirmed by the analysis of negative
pointer years when over 80% of the analysed trees responded by a sharp decrease in increment, mainly in years 1976 and 1992.
We can usually find values of monthly precipitation or monthly temperature average which can explain or help explain these
falls in the radial growth. The correlations of diameter increments with average monthly precipitation gain only positive
statistically significant values, namely for the months of May, June, July and August of the particular year. The correlations
of diameter increments with average monthly temperatures gain only negative statistically significant values, namely for the
months of June, July and September of the previous year and January and August of the particular year. In the examined area
there is a significant negative correlation between average temperatures and monthly precipitation in July, August and September.
The results of the habitual diagnostics show that with respect to the climatic conditions the health condition of the monitored
stands is relatively good. On average, the defoliation does not exceed the values ascertained in different territories of
the Czech Republic. 相似文献
102.
Since the 1980s and early 1990s, there have been few constructive developments towards a comprehensive and coherent productivity-enhancing agenda. Labor governments have often provided rhetorical support but have fought over whether industry policy represents a new protectionism or market-enhancing development policy. The Coalition in opposition and in office has generally opposed the idea of industry policy, but has continued to support ad hoc and costly policy interventions. Australia's 20 years without a recession has disguised the need to reconsider industry policy and questions of economic diversity. This article argues that dealing with problems of economic structure – particularly resource dependence and climate change adaptation – requires a revitalisation of the industry policy debate. It tracks the theory and practice of industry policy in Australia and concludes that advocates for industry policy must formulate new policy ideas outside the framework of the traditional divide between intervention and free markets. 相似文献
103.
Tom Brughmans 《Journal of Archaeological Method and Theory》2013,20(4):623-662
This review aims to expose the potential of formal network methods for archaeology by tracing the origins of the academic traditions, network models, and techniques that have been most influential to archaeologists. A brief discussion of graph theoretic applications in archaeology reveals how graph visualization and analysis was used since the 1960s in a very similar way to later network analysis applications, but did not seem to have influenced the more widespread adoption of network techniques over the past decade. These recent archaeological applications have been strongly influenced by two academic traditions, social network analysis and sociophysics. The most influential and promising techniques and models adopted from these traditions are critically discussed. This review reveals some general trends which are considered to be the result of two critical issues that will need to be addressed in future archaeological network analysis: (1) a general unawareness of the historicity and diversity of formal network methods both within and outside the archaeological discipline has resulted in a very limited methodological scope; (2) the adoption or development of network methods has very rarely been driven by specific archaeological research questions and is dominated by a few popular models and techniques, which has in some cases resulted in a routinized explanatory process. This review illustrates, however, the great potential of formal network methods for archaeology and argues that, if this potential is to be applied in a critical way, a broad multidisciplinary scope is necessary and specific archaeological research contexts should dominate applications. 相似文献
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Tom Brooking 《The Journal of imperial and commonwealth history》2013,41(3):417-435
This article discusses the role of grasslands and their products in the development of empire between 1850 and 1930. It explores the paradox that, despite the significance of introduced grasslands in terms of environmental transformation and imperial trade, most contemporary observers ignored this or took it for granted as, generally, have today's historians of empire. The article charts relations between grassland development, improvement and empire building, and examines how retrieval of this neglected story might encourage reconceptualisation of empire relationships, focusing particularly on those between New Zealand and Britain. 相似文献
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