A dendrochronological analysis of Pinus pinea L. on the Italian mid-Tyrrhenian coast

In order to assess the response of the radial growth of Pinus pinea L. to climatic variability in Central Italy, dendrochronological and dendroclimatological analyses were carried out on five different populations scattered along the Tyrrhenian coasts of the peninsula. The aim of this study is to contribute to the understanding of the ecological demands of this species, particularly in the study area. For each site total ring, early-, and late-wood width chronologies were developed. Multidimensional analyses were performed for the three tree-ring datasets in order to analyze the relations between sites chronologies. Both Principal Component Analyses and hierarchical classifications highlighted an important difference of one site in respect to the other, probably due to site characteristics. Correlation functions were performed to infer the main climatic factors controlling the radial growth of the species. For a comparative study, we limited our attention to the common interval 1926–2003 (78 years) in which the response of the tree-ring chronologies to climate at both local and regional scale was investigated. Positive moisture balance in the late spring-summer period of the year of growth is the climatic driver of P. pinea radial growth in the study area. Moreover, this study shows how low summer temperatures strongly favor the radial growth of the species.     

Climate influence on radial increment of oak (Quercus SP.) in central Poland

The study investigates the influence of climate conditions on radial increment of oak, with special concern to the situations when analysed trees formed conspicuously wider or narrower tree-rings. The research material was collected in four locations in central Poland within natural range of pedunculate and sessile oaks. The elaborated residual chronologies were correlated with CRUTS 2.1 climate data. The analyses included thermal and pluvial conditions spanning from April of the year prior to ring formation to September of the current growth year. Special interest was paid to simple water ability index that combined both temperature and precipitation during the vegetation season. Additionally, pointer year analysis was carried out to determine situations when conspicuously smaller or larger increment was formed. Investigated chronologies cover the period of 1927?C1992 (?ochów), 1845?C1992 (P?o??sk), 1868?C1992 (Pu?tusk), and 1796?C1992 (Soko?ów). The analysed oaks from sites in central Poland exhibit growth patterns comparable with those known form previous studies concerning that species, where influence of precipitation (higher and positive) and temperature (negative) have been observed. Extreme growth reactions expressed by negative and positive pointer years turned to present high dependence of analysed oak?? growth on water availability during vegetation season.     

Oak decline in a southern Finnish forest as affected by a drought sequence

We investigated the decline of a pedunculate oak (Quercus robur L.) forest growing on shallow soil at the northern distributional limit of the species in southern Finland, using the dendroclimatic approach. About 200-year-old trees in three vigour classes — healthy, declining and dead — were sampled in 2008. Annual tree-ring, earlywood and latewood widths were measured and chronologies were established. The tree-ring data were correlated with monthly and seasonal climate data. Radial increment of oaks was positively related to the June and July precipitations. This was expressed especially in total ring width and latewood width, whereas the earlywood was more influenced by the warmer winter and spring. Furthermore, the correlation between the current year earlywood width and the preceding year latewood width was higher than between the earlywood and latewood of the same year. The analyses showed that the dead oaks and part of the declining oaks had ceased growing during 2005–2007 after a decadelong summer drought series. This indicates a time lag in the oak dieback. The radial growth of the declining and the dead oaks had dropped already since the 1990s, while the healthy oaks had better longterm growth and higher adaptive capacity to climate variation.     

The Dendroecological Potential of Eucalyptus Camaldulensis Dehnhardt (River Red Gum) from the Barmah Forest,Victoria, Australia

The study of tree rings has been used for over 100 years to inform climatic and geomorphological reconstructions. In mainland Australia, no tree species are currently recognised as providing reliable sources for such studies over extensive areas. Eucalyptus camaldulensis is a widely growing species with a growth pattern that is closely linked to high levels of available moisture, such as that associated with floods. The species therefore has the potential to provide palaeoclimatic information that may be of use in hydrological and geomorphological studies. This study initially examines the microstructure of samples of E. camaldulensis taken from the Barmah Forest to assess the applicability of the species to dendroecological investigation. It is found that samples of the species exhibit ring‐like structures, although there are areas of the samples that contain zones of growth without clear ring boundaries. The patterns of growth rings and zones are found to be common to many trees at a site, although the level of variability of pattern from tree to tree is high. Options for future development of the approach described here are to combine ring studies with isotopic‐based analysis to provide a combination of tree age and climatic history.     

Tree-ring based temperature reconstruction for the west Qinling Mountains (China): linkages to the High Asia,solar activity and Pacific-Atlantic Ocean

We developed a Faxon fir (Abies faxoniana) tree-ring width chronology at the timberline in the western Qinling Mountains, China. Herein February–July mean temperature was reconstructed for Zhouqu in the western Qinling Mountains back to AD 1650 based on the standard chronology. The climate/tree-growth model accounts for 43.5% of the instrumental temperature variance during the period 1972–2006. Spatial correlation analyses with the gridded temperature data shows that the temperature reconstruction captures regional climatic variations over central and southeast China, and strong teleconnections with the nearby High Asia. There is a good agreement with cold and warm periods previously estimated from tree-rings in Nepal, India and southwest China. The temperature re-construction indicates that there was pronounced cooling in Zhouqu during the Maunder Minimum (late 1600s to early 1700s). The cold period (1813–1827) of the temperature reconstruction coincide with the volcanic eruptions. Significant spectral peaks are found at 56.9, 22.3, 11.4, 2.9, 2.8, 2.6, 2.2 and 2.0 years. The spatial correlation patterns between our temperature reconstruction and SSTs of the Atlantic and Pacific Oceans suggest a connection between regional temperature variations and the atmospheric circulations. It is thus revealed that the chronology has enough potential to reconstruct the climatic variability further into the past.     

Growth responses of Norway spruce (<Emphasis Type="Italic">Picea abies</Emphasis> (L.) Karst.) to the climate in the south-eastern part of the Českomoravská Upland (Czech Republic)

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.     

Growth of Rural Industries in Post-reform China: Patterns,Determinants and Consequences

The first question addressed by this paper relates to the very high growth rates achieved by China's rural industries during the post-reform period. While growth rates have undoubtedly been extremely high, they can only be put in a proper perspective when growth in different components of the sector (i.e. township- and village-owned and privately owned industries) is examined separately and compared with performance before the reforms. In this regard, an important finding of the paper is that as far as township and village industries are concerned, growth rates in the post-reform period do not represent a sudden break from the rates of the earlier period — particularly the 1970s. It is mainly in the emergence and growth of private enterprises that the growth experience of the 1980s differs substantially from that of the 1970s. The sharp decline in the growth of all rural industries in 1989 does not appear to mark a reversal in their growth environment, but the beginning of a period of consolidation and rationalization; and, contrary to popular notion, private enterprises are not the worst sufferers in this process. Finally, the paper looks at regional imbalance. Historically, rural industries in China have been concentrated more in the eastern provinces along the coast, and this regional concentration has increased during the post-reform period of high growth.     

The Potential of Tree Rings in Eucalyptus pauciflora for Climatological and Hydrological Reconstruction

We investigate the causes of variability in a tree‐ring chronology comprising data from Eucalyptus pauciflora Sieb. Ex. Spreng. at the alpine treeline on the Kosciuszko Plateau in New South Wales, Australia. Following verification of crossdating in a subset of the available data, we found that ring width correlates significantly with net radiation, precipitation and mean minimum and maximum air temperature during the preceding winter and spring of the growing season. Our results for spring are consistent with the impact of climate on tree growth in alpine woodlands reported in previous studies. Analyses of snow‐depth data revealed negative correlations with ring width throughout winter and spring. Our results indicate that low temperature and high precipitation during winter negatively affect the growth of E. pauciflora by prolonging spring snow cover. Ring width also correlates significantly with an index of soil dryness and flow in rivers with their headwaters in the Kosciuszko plateau. Given the apparent sensitivity of our chronology to climate and snow conditions, our results suggest that tree‐ring chronologies comprising data from E. pauciflora at the alpine treeline have potential for climatological and hydrological reconstruction in southeast Australia.     

The Influence of Indoor Climate Control on Risk for Damages in Naturally Ventilated Historic Churches in Cold Climate

This article analyzes the indoor climate that creates risk of damages in naturally ventilated churches in the cold climate of Estonia. Indoor temperature and humidity were measured over a one-year period and the results were analyzed on the basis of damage functions: mold growth, risk of cracking and fracturing of wooden objects, and delamination of the gesso layer of panel paintings.

In unheated churches, one of the most dominant problems was very high relative humidity throughout the year, creating a high risk for mold and algae growth. Churches may need background heating to avoid freezing during a long cold winter that causes low surface temperatures of massive walls during the spring–summer period. It was found that mold risk was significantly lower in heated churches than in unheated or intermittently heated churches. The risk of mold growth was not decreased by the use of intermittent heating.

In heated churches, overheating (room temperature >+10ºC) causes a RH below 50% during cold periods, and the favorable period for irreversible response of panel paintings was significantly longer, so there is a higher risk that the gesso may crack or delaminate. From the point of view of the cracking and fracturing of wood, indoor climate conditions are in the safe range for most of the year.     

Long-term trends in planetary wave activity (2–15 days) at 80–100 km inferred from radio wave absorption

The daytime radio wave absorption in the lower ionosphere measured by the A3 method (oblique incidence on the ionosphere) in central and southeastern Europe is used to study long-term trends in the planetary wave activity in the period range of 2–15 days in the upper middle atmosphere. In central Europe we have found no trends in the 1960s and 1980s, but a positive trend in the 1970s (early 1970s- early 1980s); in southeastern Europe we have not established any trend in the 1970s, but a positive one in the 1980s (beginning in late 1970s). These trends are of non-solar origin. They are possibly an indication of changes of anthropogenic origin in the Earth's atmosphere.     

西安市人口的分布变动研究

基于三次人口普查数据,对西安市80年代以来的人口分布变动进行了系统研究。结果表明:西安市在20世纪80年代便已形成"中心区人口减少、内圈和中圈人口快速增长、外圈人口低速增长"的区域差异格局,90年代这种区域差异格局更明显。通过人口分布模型的回归拟合,尝试性预测了西安市未来人口分布的趋势。结果显示:2010年西安市人口分布的峰值将出现在距市中心约2.5km的城墙与二环线之间。最后探讨了西安市人口分布变动的促进机制。     

Dendrochronological dating of a wooden causeway in Finland

A mean ring‐width chronology for Scots pine in eastern Finland has been compiled based on living trees and dendrochronologically dated historical timber constructions. As an application of this master chronology, a young archaeological site near the town of Hämeenlinna, southern Finland, was dated. A previous assumption of the age of this site was that it could even be medieval. The construction was not older than 160 years, the road having been built after 1828, the year of growth of the outermost tree rings of the samples. A new pine chronology for southern Finland extending to the year AD 1539 is presented and it is now applicable for precise dating purposes in this area.     

道光十一年冬季严寒对京杭大运河运作状态的影响

利用清代地方志、档案等文献资料,复原了道光十一年(1831-1832年)冬的严寒实况,在此基础上分析了严寒对京杭大运河各段运作状态的影响。研究表明,道光十一年冬的严寒涉及我国整个东部地区,是此前百年中最冷的一年。在漕政日益败坏的道光年间,正常情况下的漕河整治与管理已属不易,极端气候更增加了其困难。因地理位置、面临任务以及对气候变化敏感度的不同,此次严寒对各河段的影响也就各有差异。山东运河远离黄河,水浅冰厚,主要表现为河道疏浚的困难;苏北运河地处黄运交汇,凌汛多发,主要表现为堤防修守的艰辛;江南徒阳运河虽出现了漕船通行的延迟,但相对涝灾而言,寒冷气候的影响是其次的原因。     

New results on the dip equator and the equatorial electrojet in India

The geophysical implications are examined of the continuing southward migration of the magnetic dip equator in India since 1965, its precise ground location in 1971, and thereafter its drift at 1–6 km/yr accelerating to 7 km/yr in the mid-1980s near its mean central position in the 80-yr secular oscillation, estimated to be about 10 km south of Trivandrum. Simultaneously its drift northwards near the antipodal point at Huancayo Observatory, in Peru (South America), is also observed.The ground projection of the mean axis of the equatorial electrojet for 1980 is clearly delineated about 55 km to the north of the dip equator in India, with positive Sq(Z) values of 25 nT recorded right on the dip equator, based on the ground geomagnetic survey 1971 and the magnetometer array experiment of 1980. The half-width and midday peak total current intensity of the Indian electrojet are determined from the H data recorded at Trivandrum, Annamalainagar and Hyderabad for the solar minimum year 1976 (146 ± 46 km, 137 ± 25 Amp/km) and the maximum year 1980 (169 ± 39 km, 203 ±49 Amp/km), assuming a uniform west-east current band model at a height of 107 km centred on its newly discovered axis. These new results are quite different from those of earlier determinations. Severe induction anomalies observed in the region due to subsurface geological bodies are also appropriately incorporated.     

Sub-fossil wood from the Rucianka raised bog (NE Poland) as an indicator of climatic changes in the first millennium BC

The dendrochronological studies were carried out on very well preserved sub-fossil pine wood found in the biogenic deposits of the Rucianka raised bog (NE Poland). Local floating chronologies, covering the period 990-460 cal BC, were dated on the basis of radiocarbon analyses. Growth depressions in annual treering widths indicated periodical deterioration of the environmental conditions, which affected tree growth. Identified germination and dying-off phases (GDO) should be related to the wetter climatic periods. The extinction of trees took place during periods of higher groundwater level which, in turn, caused favourable conditions for growth of young pines.     

Some Evidence for Seasonality amongst Later Stone Age Hunter-gatherers in Southern Africa

Abstract

The Later Stone Age (LSA) period in Southern Africa is characterised by a succession of cultural traditions. The LSA hunter-gatherer populations were ancestral to the present-day San. They moved around in small bands, within a semi-fixed territory visiting open air and shelter sites to coincide with available resources.

The hunter-gatherers filled every niche in the environment, including the high mountains, deserts and semi-deserts, bush savanna and grass lands. They were well aware of the food sources available in their territories during the course of a year and utilized these opportunities. As winters in southern Africa are relatively mild, and most regions have foods available throughout the year, seasonality is difficult to demonstrate.

In only a few instances there is some evidence for seasonal use or seasonality. Age profiles of seals at Elands Bay Cave suggest short occupation periods during late winter and early spring. In the high mountains of South Africa and Lesotho, where winters are cold and frost and snow common, the faunal and floral remains suggest occupation during late spring, summer and early autumn. Abbot's Cave in the semi-arid central Karoo was used as a hunting lodge during September, relating to the lambing season and migratory behaviour of springbok (Antidorcas marsupialis).     

Climatic Change

The methods of physical climatology are used to explain climatic variations during the contemporary epoch and in the geological past. Contemporary climatic change is found to depend to a considerable extent on variations in atmospheric transparency. These variations, which change the amount of solar radiation reaching the earth's surface, are associated with the changeable level of volcanic activity. Climatic changes in the geological past are also explained in terms of variations in atmospheric transparency and the changing distribution of the earth's land and sea areas, which influenced circulation in the hydrosphere. On the basis of established regularities in past climatic change, the possible future trend of climatic evolution is suggested. Although the current cooling trend could conceivably lead to renewed expansion of glaciation, this is considered highly unlikely in view of the increasing amount of heat generated by man's growing use of energy. The additional heat may be sufficient in the long run to melt the polar ice and introduce a climate into the middle and high latitudes typical of warm interglacial epochs. Actually, even before this, technology may enable man to eliminate the polar ice artificially. The beneficial and harmful effects of such as step are briefly considered.     

Ancient olive DNA in pits: preservation,amplification and sequence analysis

The olive tree (Olea europaea) was domesticated by vegetative propagation of selected wild individuals with superior fruit. Later, new cultivars were established repeatedly from feral trees or from crosses between wild, feral, and domesticated trees. Thus the genetic background of many contemporary domesticated lines is a mixture of ancient cultivars and local wild trees. Ancient DNA may illuminate the complicated process of olive domestication because such DNA sequences provide data about ancient genomes that existed closer to the domestication events. Well preserved DNA must be available for such studies, even though in the Mediterranean region, where olive cultivation took place, the climatic conditions are not favorable for DNA preservation. To select for well preserved pits we measured their proportions of lignin by IR spectroscopy, and correlated this with parameters of DNA quality such as template length in an olive-specific repeat array, and template quantity as determined by real-time PCR amplification. Archaeological pits that passed these tests did contain high quality ancient DNA. We present the first ancient olive DNA sequences and compare them to modern wild, feral and domesticated lines.     

About the origin of high energy electrons in the inner radiation belt

A large flux of > 100 MeV electrons were registered in the inner radiation belt on low-altitude satellites. The origin of that flux is discussed. It appears that slow radial diffusion (D_o = 10⁻¹³ 1/s) gives a low probability for penetration of these electrons to small L from the boundary of magnetosphere because of synchrotron radiation energy losses. It is found that they can enter to the inner belt region without such losses after great magnetic storms when high speed radial diffusion sometimes takes place. Two great storms on 8–9 Feb.] 986 and 24 March 1991 are examples when one can directly observe a penetration of energetic electron fluxes into magnetosphere. The assumption about their Jovian origin is discussed.     

基于黄土高原南部地区历史文献记录的唐代气候冷暖波动特征研究

本文基于黄土高原南部地区历史文献记录 ,对唐代气候冷暖波动特征进行初步研究。研究表明 ,799AD前后存在一次百年尺度的气候转寒 ,在 84 5 AD、880 AD附近还存在两次数十年尺度的气候波动。在数十年时间尺度上 ,气候寒冷与较高的气候变率相伴出现。唐代相应地区旱涝资料中没有发现冷暖变化与干湿变化在十年尺度上有显著的线性相关性。最后我们就气候波动与社会发展之间某些耦合现象作一初步的讨论。