Net Increment Research Articles

Estimation of aboveground biomass and net biomass increment in a cool temperate forest on a landscape scale

AbstractI clarified aboveground biomass (AGB), net biomass increment (NBI) and its spatial heterogeneity in a cool temperate forest on a landscape scale (>2,200 ha). The relationships among AGB, NBI, and the size frequency distribution of trees of each stand were examined by combining an analysis of vegetation using aerial photographs, and data from 146 inventory plots (28.8 ha in total). This area included natural broad‐leaved stands, harvested broad‐leaved stands, and artificial conifer plantations. A −3/2 power distribution density function was applied to the individual mass frequency distribution of each plot. Estimated AGB in carbon (C) equivalent was 480–5,615 g C m−2 (3,130 g C m−2 on average), and NBI was −98 to 436 g C m−2 year−1 (83.0 g C m−2 year−1 on average). NBI had a single significant relationship with the reciprocal of theoretical maximum individual mass, while NBI was not significantly related to AGB. My results showed that, on a landscape scale, AGB and NBI strongly depend on the size structure of forest stands.

Model of single bubble sonoluminescence

The temperature within and the sonoluminescence characteristics of a stable inert-gas single bubble grown in water under some given conditions are computed by using a model that is as sufficiently complete as we can manage, except that possible chemical reactions within the bubble are neglected. We work with several different versions of the equation describing the motion of the bubble wall, which are usually considered to give merely slight differences; or vary a parameter in the formula calculating the net increment of the water condensed at the bubble wall. It is found that the final outcomes of the temperature and the sonoluminescence can be significantly different in some cases. This illustration points to the importance of differentiating among the various seemingly similar equations and of adopting the correct value of the parameter used in the computation model of a single bubble.

Carbon cycling and budget in a forested basin of southwestern Hokkaido, northern Japan

AbstractQuantification of annual carbon sequestration is very important in order to assess the function of forest ecosystems in combatting global climate change and the ecosystem responses to those changes. Annual cycling and budget of carbon in a forested basin was investigated to quantify the carbon sequestration of a cool‐temperate deciduous forest ecosystem in the Horonai stream basin, Tomakomai Experimental Forest, northern Japan. Net ecosystem exchange, soil respiration, biomass increment, litterfall, soil‐solution chemistry, and stream export were observed in the basin from 1999–2001 as a part of IGBP‐TEMA project. We found that 258 g C m−2 year−1 was sequestered annually as net ecosystem exchange (NEE) in the forested basin. Discharge of carbon to the stream was 4 g C m−2 year−1 (about 2% of NEE) and consisted mainly of dissolved inorganic carbon (DIC). About 43% of net ecosystem productivity (NEP) was retained in the vegetation, while about 57% of NEP was sequestered in soil, suggesting that the movement of sequestered carbon from aboveground to belowground vegetation was an important process for net carbon accumulation in soil. The derived organic carbon from aboveground vegetation that moved to the soil mainly accumulated in the solid phase of the soil, with the result that the export of dissolved organic carbon to the stream was smaller than that of dissolved inorganic carbon. Our results indicated that the aboveground and belowground interaction of carbon fluxes was an important process for determining the rate and retention time of the carbon sequestration in a cool‐temperate deciduous forest ecosystem in the southwestern part of Hokkaido, northern Japan.

Evaluating organisational designs in the forestry wood supply chain to support Forest Owners’ Cooperations

In the coming decades European forest-based industries could face a lack of wood as raw material because of low mobilisation of the net annual increment, even though there is a huge amount of green inventory in European forests. The main obstacle to systematic exploitation of the wood inventories is small-scale ownership. Forest Owner Cooperations (FOCs) try to overcome this by jointly undertaking activities including harvesting, transporting, marketing and accounting. In this paper, the concept of business-process engineering is applied to FOCs in Austria and Germany. Using case studies, productivity is compared for three business process models that are implemented by FOCs. Because of the lack of consistent data about time spent by various process owners for different processes, interactions are used as an indicator of process efficiency of the alternative business process models. The main contribution of the paper is to provide a guideline to compare different FOC business process models with respect to the interactions of participants. Reducing the interaction (or transaction) cost of timber supply is one way to improve the availability of wood as a raw material. It can be shown that the proposed dividend model requires less process interactions than other models examined in this paper.

Cellular insulin resistance in Epstein-Barr virus-transformed lymphoblasts from young insulin-resistant Japanese men

The metabolic syndrome is characterized by a blunted insulin-mediated glucose uptake in various cell types. We compared the glucose uptake characteristics of Epstein-Barr virus (EBV)–transformed lymphoblasts obtained from young men with vs without metabolic and cardiovascular evidence of metabolic syndrome. From a population of 218 men, 20- to 25-year-old, 10 men with a systolic blood pressure (BP) ≥130 mm Hg and family history of hypertension were assigned to a high BP (HBP) group, and 10 with a BP ≤110 mm Hg, and no family history of hypertension was assigned to a low BP (LBP) group. Multiple clinical and metabolic characteristics were examined in both groups and compared. Peripheral lymphocytes from HBP and LBP subjects were EBV-transformed, and the glucose transporter (Glut)–mediated glucose uptake from each group was compared in lymphoblasts. Body mass index, fasting glucose, immunoreactive insulin, insulin resistance index based on a homeostasis model assessment (HOMA-R), and total and low-density lipoprotein cholesterol were significantly higher in the HBP than the LBP subgroup (whole-body insulin resistance). Baseline Glut-mediated and Glut-mediated insulin-stimulated glucose uptake by lymphoblasts from the HBP group were significantly lower than by lymphoblasts from the LBP group (cellular insulin resistance). The net increment in Glut-mediated glucose uptake by insulin was inversely correlated with HOMA-R. In conclusion, cellular insulin resistance in EBV-transformed lymphoblasts is associated with young Japanese subjects with HBP. The net increment in Glut-mediated glucose uptake by insulin in lymphoblasts may be a useful intermediate phenotype to study genetic aspects of the metabolic syndrome.

EFFECTS OF WATER STRESS ON PHOTOSYNTHESIS AND CARBON ALLOCATION IN CUNNINGHAMIA LANCEOLATA SEEDLINGS

Changing the allocation of carbohydrates to various organs is a central mechanism by which plants cope with temporally or spatially varying environments. Hence, a primary objective of eco-physiological research is to understand when and how this process is affected by specific external conditions. Chinese fir (Cunninghamia lanceolata) is one of the most important timber species in Southern China due to its fast growth and good timber quality. Due to large-scale afforestation/reforestation activities, Chinese fir stands, most of which are plantations, have expanded rapidly since the 1950s, and, in particular, since the 1980s, with both the area and standing volume having more than doubled. Therefore, to understand the carbon allocation in Chinese fir in response to varying soil moisture conditions, we studied the photosynthetic response and changes in photosynthate allocation of 2-year-old Chinese fir seedlings under different water treatments. The experiment was conducted in the Subtropical Forestry Experimental Center of the Chinese Academy of Forestry located in Fengyi of Jiangxi Province. Eighty potted 2-year-old Chinese fir seedlings were grown for one growing season under two water treatments: a water stress treatment in which one third the normal water supply was applied and a control (normal water management). The net photosynthetic rate (P_(n)) in response to photosynthetic photo flux density (PPFD) were measured using a LI-6400 portable photosynthesis system from 8:00 to 11:00 on clear days in late June. Air temperature and relative humidity in the chamber were maintained at (25±1)℃ and 70%±5%. Carbon allocation in seedlings under the two water treatments was measured in the morning of early July using a 13C pulse labeling technique. The initial CO_(2) concentration in the labeling chamber was about 1000 #mu#mol•mol~(-1) and each labeling lasted 40 minutes. The current-needles, 1-year old needles, branches, stems, fine roots and coarse roots were sampled on day 1, day 3, day 7 and day 21 following labeling. Samples were dried, grinded to a powder, combusted, and then analyzed on an isotope ratio mass spectrometer to measure the stable carbon isotope ratio. Our results showed that water stress did not alter the photosynthetic characteristics of Chinese fir seedlings. The #delta#~(13)C values and net ~(13)C ratio (N~(13)CR), i.e., the ratio of the net increment of ~(13)C to the natural total carbon, of the seedlings decreased in the water-stress treatment. The effect of water deficit on the #delta#~(13)C values and N~(13)CR in shoots was more significant than in roots. The shoot biomass under water stress was reduced remarkably, while little changes were found for root biomass. Water stress had a more significant effect on current-needles than other organs. The #delta#~(13) values, N~(13)CR and dry weight of current-needles under water stress were lower than in the control. The more rapid decline of N~(13)CR in current-needles of water-stressed seedlings 21 days following labeling indicated that there was an increase in the export of photosynthetic products. The growth decline of the current needles under water stress caused a decrease in leaf area resulting in a reduction in total photosynthesis. Under water stress, more photosynthetic products were transferred to belowground biomass, especially to the fine roots. As a result, carbon allocation patterns were altered and higher root:shoot ratios were found in seedlings experiencing water stress!in comparison to seedlings under conditions of normal water management.

Tree biomass and net increment in an old aspen forest in New Mexico

Previous work indicated that net ecosystem production (NEP) was negative in a 90-year-old aspen ( Populus tremuloides Michx.) forest in the Tesuque watershed of northern New Mexico. The loss of nitrogen (N) in streamwater was very low for this forest, which would be surprising if NEP were negative for a substantial period. We remeasured live tree biomass of this case-study forest after an additional 27 years of growth, as a long period with negative NEP would likely demonstrate declining live tree biomass. Contrary to expectation, live tree biomass increased substantially through this period (averaging 1.37 Mg ha −1 yr −1). The net increment for this period was relatively high (within 10% of the mean annual increment) well into the second century of stand development in this high-elevation aspen forest. We conclude that the high retention of N was not anomalous given the later increase in live tree biomass, and we expect that NEP had not remained negative for a long period.

A process-based model of forest ecosystems driven by meteorology

Although anthropogenic climate change is generally acknowledged as a reality, tree level models that respond to the boundary conditions expected to change as a result of global warming are largely non-existent. Consequently, a process-based model of individual tree growth driven by meteorology was developed. The model, Forest v5.1 predicts the growth of deciduous and coniferous species for the Great Lakes Region of North America. The model uses a daily time step and was written with two overriding design tenets in mind: (i) model drivers must mimic controls on plant growth as they exist in nature and (ii) model initialization must be achievable through the use of typical forest inventory field plot data. Forest v5.1 predicts the carbon, nutrient and water cycle as these influence tree growth and with particular emphasis on light interception and assimilation. Model outputs are both in dimension as well as biomass. Sensitivity analysis shows the importance of parameters that characterize maximum photosynthetic potential and scaling factors. A comparison of observed and predicted growth trajectories for 25 years indicates tree diameter development exhibits useful levels of precision (−0.12 to 0.11 cm year −1) relative to an empirical model. The model, using HadCM2-generated weather, projects that water use efficiency will increase as a result of climate change. Net basal area increment increases on average by 0.17 m 2 ha −1 year −1 relative to a projection of current climate.

The utility of the zero-inflated Poisson and zero-inflated negative binomial models: a case study of cross-sectional and longitudinal DMF data examining the effect of socio-economic status.

To examine the utility of the zero-inflated Poisson (ZIP) and zero-inflated negative binomial (ZINB) modelling approaches for modelling four sets of dental caries data from the same cohort study [with particular attention to the influence of childhood socioeconomic status (SES)]: cross-sectional data on the deciduous dentition at age 5 years; cross-sectional data on the permanent dentition at age 18 and 26 years; and longitudinal data on caries increment between ages 18 and 26 years. Data on dental caries occurrence at ages 5, 18 and 26 years were obtained from the Dunedin Multidisciplinary Health and Development Study (DMHDS). ZIP and ZINB models were fitted to the cross-sectional (n = 745) and longitudinal (n = 809) data sets using Stata (Intercooled Stata 7.0). The dependent variables for the three cross-sectional analyses were the DMFS indices at age 5, 18, and 26 years, and net DFS increment (NETDFS) was the dependent variable for the longitudinal analysis. The empty ZIP model was a poor fit for all four data sets, whereas the empty ZINB model showed good fit; consequently both the cross-sectional and longitudinal analyses were conducted using ZINB modelling. Being in the high-SES group during childhood was associated with a greater probability of being caries-free by age 18 years, over and above that which would be expected from the negative binomial process. Low childhood SES also had the largest coefficient in the modelling of the negative binomial process, but at age 5 years, where the adjusted mean dmfs score in the low-SES group was 6.8 (compared with 4.7 and 2.9 in the medium- and high-SES groups, respectively). The substantial SES differences which existed at age 5 years (in the deciduous dentition) had reduced somewhat by age 18 years, and had widened again by age 26 years. In the longitudinal analysis, "baseline" caries experience (age 18-year DMFS) was a predictor both of being an extra zero and of caries severity. This investigation of the utility of the zero-inflated approach for modelling both cross-sectional and longitudinal caries data has shown that ZIP/ZINB models can provide new insight into disease patterns. It is anticipated that they will become increasingly useful in epidemiological studies that use the DMF index as the outcome measure.

Fifty years of partial harvesting in a mixed mesophytic forest: composition and productivity

Long-term silvicultural trials contribute to sustainable forest management by providing a better scientific understanding of how forest ecosystems respond to periodic timber harvesting. In this study, species composition, diversity, and net periodic growth of tree species in a mixed mesophytic forest in the central Appalachians were evaluated after about a half century of management. Three partial cutting practices on 18 research compartments and on 3 unmanaged reference compartments were evaluated (1951–2001) on 280 ha. Single-tree selection, diameter-limit harvesting, and timber harvesting in 0.162-ha patches were assessed on three northern red oak site index50 (SI) classes: 24, 21, and 18. Shannon–Weiner's diversity index (H′) declined from the first (1951–1959) to last (1987–2001) measurements and was related to both SI (P = 0.004) and treatment (P = 0.009). Sugar maple (Acer saccharum Marsh.) and red maple (Acer rubrum L.) were the two most abundant species in recent years (1987–2001); in contrast, in initial inventories (1951–1959), northern red oak (Quercus rubra L.) and chestnut oak (Quercus prinus L.) were most abundant. Net periodic annual increment (PAI) of merchantable trees (DBH ≥12.7 cm) was related to both SI (P = 0.004) and treatment (P = 0.003). Mean PAI ranged from 4.6 m3·ha–1·year–1 for single-tree selection to 2.5 m3·ha–1·year–1 for unmanaged reference areas across all SI classes. The decline of oak species suggests that only intensive and specific forest management focused on maintaining oak species can obtain historical levels of diversity.

Measurement of the serum lipoprotein lipase concentration is useful for studying triglyceride metabolism: comparison with postheparin plasma

The catalytically inactive form of lipoprotein lipase (LPL) is detectable at high levels in serum, although its physiologic role remains unknown. The aim of this study was to elucidate the clinical significance of serum LPL compared with postheparin LPL or the net increment (Δ) of LPL (postheparin − preheparin LPL). We measured the LPL mass before and 15 minutes after the injection of heparin in 164 subjects with hyperlipidemia. LPL mass was measured by a sensitive sandwich enzyme-linked immunosorbent assay (ELISA). Serum LPL was one fifth of the postheparin LPL concentration. There was a weak correlation between the serum LPL and postheparin LPL concentrations ( r = .225, P ≤ .005). The Δ LPL concentration was strongly related to the postheparin LPL concentration ( r = .965, P ≤ .0001), but not to the preheparin LPL mass, suggesting that the weak correlation between serum LPL and postheparin LPL levels was attributable to contamination of postheparin plasma by pre-existing LPL (preheparin LPL). Both serum and postheparin LPL were significantly lower in diabetic patients and in subjects with high levels of triglyceride or low levels of high-density lipoprotein (HDL). Serum LPL was correlated negatively with triglyceride, remnants, and insulin resistance and was positively correlated with HDL cholesterol and low-density lipoprotein (LDL) size. Postheparin LPL was strongly correlated with HDL cholesterol, but not with other parameters, as was serum LPL. Δ LPL mass did not show a closer association with triglyceride metabolism than postheparin LPL or preheparin LPL. In conclusion, serum LPL measurement is simple and seems to be useful for studying triglyceride metabolism.

Regeneration and growth of pioneer and shade‐tolerant rain forest trees in Tonga

Size distributions were analysed for 25 tree species (4331 individuals) from among those recorded in 64 plots in the Vava'u island group, Kingdom of Tonga, in 1995. These species were assigned to four groups representing their regeneration patterns (association with either gaps or low light microsites as seedlings and/or as larger trees). The distribution of tree diameters was calculated from early‐ (n = 28) and late‐successional (n = 36) plots to determine where the species were regenerating. Six years later 1110 of these trees were remeasured. Average net growth increment was used as an estimate of growth rate, and maximum growth increment as potential growth rate, for each species. Most shade‐tolerant, late successional species had low growth rates and a lognormal size distribution in late‐successional plots, as expected. One species in this group, however, had the highest estimated average growth rate in the study. The second group of species, found in shade as seedlings but abundant as small trees in early‐successional plots (e.g., “mid‐successional"), as well as the third group, found in gaps as seedlings but most abundant in late‐successional plots, shared high growth rates. The fourth group, pioneer species establishing in large gaps, were not regenerating in late‐successional plots but, unexpectedly, had estimated growth rates comparable to the other groups. Tongan rain forest has diverse regeneration functional types, analogous to those found in richer continental tropical forest, but perhaps represented by different numbers of tree species.

Diurnal and seasonal changes in stem increment and water use by yellow poplar trees in response to environmental stress.

To evaluate indicators of whole-tree physiological responses to climate stress, we determined seasonal, daily and diurnal patterns of growth and water use in 10 yellow poplar (Liriodendron tulipifera L.) trees in a stand recently released from competition. Precise measurements of stem increment and sap flow made with automated electronic dendrometers and thermal dissipation probes, respectively, indicated close temporal linkages between water use and patterns of stem shrinkage and swelling during daily cycles of water depletion and recharge of extensible outer-stem tissues. These cycles also determined net daily basal area increment. Multivariate regression models based on a 123-day data series showed that daily diameter increments were related negatively to vapor pressure deficit (VPD), but positively to precipitation and temperature. The same model form with slight changes in coefficients yielded coefficients of determination of about 0.62 (0.57-0.66) across data subsets that included widely variable growth rates and VPDs. Model R2 was improved to 0.75 by using 3-day running mean daily growth data. Rapid recovery of stem diameter growth following short-term, diurnal reductions in VPD indicated that water stored in extensible stem tissues was part of a fast recharge system that limited hydration changes in the cambial zone during periods of water stress. There were substantial differences in the seasonal dynamics of growth among individual trees, and analyses indicated that faster-growing trees were more positively affected by precipitation, solar irradiance and temperature and more negatively affected by high VPD than slower-growing trees. There were no negative effects of ozone on daily growth rates in a year of low ozone concentrations.

Seven decades of stand development in mixed and pure stands of conifers and nitrogen-fixing red alder

Early insights on the effects of N2-fixing red alder (Alnus rubra Bong.) on conifer forests came largely from two case studies dating from the 1920s at Wind River, Washington (low soil N), and Cascade Head, Oregon (high soil N). These classic experiments were remeasured after 70 years of stand development. The pure conifer stand at Wind River showed near-zero net increment in stem mass for the past 20 years, with stem mass remaining near 120 Mg/ha. Conifer stem mass in the mixed stand continued to increase at 4.5 Mg·ha–1·year–1, reaching 230 Mg/ha at age 72. The alder mass declined over this period from about 70 Mg/ha near age 50 to just 10 Mg/ha at age 72 as a result of increasing dominance of tall Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees. The pure conifer plot at Cascade Head reached a stem mass of 600 Mg/ha at age 74 years compared with 312 Mg/ha in the mixed stand (conifers, 200 Mg/ha; alder, 112 Mg/ha) and 173 Mg/ha in the pure alder plot. The long-term impacts of alder appeared to remain very strong after seven decades, greatly increasing ecosystem productivity at the N-poor Wind River site and reducing productivity at the N-rich Cascade Head site.

STREAM NUTRIENT UPTAKE, FOREST SUCCESSION, AND BIOGEOCHEMICAL THEORY

Theories of forest succession predict a close relationship between net biomass increment and catchment nutrient retention. Retention, therefore, is expected to be greatest during aggrading phases of forest succession. In general, studies of this type have compared watershed retention efficiency by monitoring stream nutrient export at the base of the catchment. As such, streams are viewed only as transport systems. Contrary to this view, the nutrient spiraling concept emphasizes transformation and retention of nutrients within stream ecosystems. In this paper, we address how biogeochemical theory developed for forests may apply to lotic ecosystems in the context of catchment-level succession. Using measures of nutrient spiraling to document uptake, we focus on later seral stages by com- paring streams draining second-growth (i.e., 75-100-yr stands) and old-growth (i.e., >400 yr) forests of the southern Appalachian Mountains, USA. Standing stocks of large woody debris (LWD) in old-growth streams were orders of magnitude greater than in second- growth streams where logging practices removed LWD from stream channels. Debris dams were also more frequent in old-growth streams. Solute injections were used to quantify retention of dissolved inorganic phosphate (P04-P), the limiting nutrient in Appalachian streams. Uptake velocities in old-growth streams were significantly greater than in second- growth streams and were closely related to debris dam frequency, LWD volume, and the proportion of fine-grained (<2 mm) sediments present in the stream bed. These data suggest that streams of old-growth forests have greater demand for P04-P compared to streams draining aggrading second-growth catchments. Finally, we present a schematic model of forest succession, aquatic-terrestrial interaction, and biogeochemical functioning in stream ecosystems emphasizing that the successional time course of retention in lotic ecosystems may be very different than that predicted for forests.

Influence of oral contraceptive use on endothelial t-PA release in healthy premenopausal women.

We determined the influence of oral contraceptives (OC) on the capacity of the endothelium to release tissue-type plasminogen activator (t-PA). Twenty-three healthy premenopausal women were studied: 12 nonusers and 11 users of OC. Net endothelial release rates of t-PA were calculated as the product of the arteriovenous concentration gradient and forearm plasma flow in response to intra-arterial bradykinin (BK: 12.5-50 ng. 100 ml tissue(-1) x min(-1)) and sodium nitroprusside (SNP: 1.0-4.0 microg x 100 ml tissue(-1) x min(-1)). Net release of t-PA antigen and increment in t-PA activity across the forearm to BK increased (P < 0.01) in a dose-dependent fashion and to similar extents in the nonusers and users of OC. At the highest BK dose, net release of t-PA antigen was 64.5 +/- 8.2 and 66.2 +/- 15.4 ng x 100 ml tissue(-1) x min(-1) in the nonusers and users of OC, whereas the net increment in t-PA activity was 18.6 +/- 3.0 and 16.0 +/- 2.0 IU. 100 ml tissue(-1) x min(-1), respectively. There was no effect of SNP on t-PA release in either group. These results indicate that endothelial t-PA release is not altered in premenopausal women who use oral contraception.

The cost utility of bisphosphonate treatment in established osteoporosis.

Hip fracture is an important and costly problem. Bisphosphonate therapy prevents hip and other fractures among women with established osteoporosis, but there are few published economic evaluations of this treatment. To assess the cost-effectiveness of risedronate, a recently launched bisphosphonate for the prevention of fractures among women with established osteoporosis. A state transition Markov model of established post-menopausal osteoporosis based upon randomized clinical trial data was developed. Uncertainty underlying model parameters and outcomes was dealt with using traditional sensitivity analysis and stochastic sensitivity analysis to produce quasi-95%CIs. We focussed on patients aged approximately 75 years, since this population most closely matches the randomized controlled trial, and is typical of osteoporosis patients in the UK. The baseline model of treating a cohort of 1000 75-year-old women for 3 years with risedronate and then modelling the costs and benefits over their expected lifetimes, produced net savings of pound sterling 786 000 for the treatment group per 1000 treated women, (95%CI pound sterling 1.55m savings to pound sterling 47000 extra costs). Restricting the horizon of the analysis to only three years led to a small net cost of pound sterling 138 000 per 1000 treated women (95%CI pound sterling 196 000 savings to pound sterling 477 000 extra costs) with a net increment in Quality Adjusted Life years (QALYs) of 16 per 1000 treated women. This resulted in a cost per QALY of pound sterling 8625 per treated woman. In this example, the use of risedronate therapy in 75-year-old women at high risk of hip fracture leads to an improvement in quality of life with possible cost savings. Restricting the analysis to a time horizon of only three years leads to a QALY gain at a modest net cost.

Stemwood volume increment changes in European forests due to climate change—a simulation study with the EFISCEN model

AbstractThis paper presents the results of a modelling study of future net annual increment changes in stemwood of European forests owing to climate change. Seven process‐based growth models were applied to 14 representative forest sites across Europe under one climate change scenario. The chosen scenario was the HadCM2 run, based on emission scenario IS92a, and resulted in an increase in mean temperature of 2.5 °C between 1990 and 2050, and an increase in annual precipitation of 5–15%. The information from those runs was incorporated in a transient way in a large‐scale forest resource scenario model, EFISCEN (European forest information scenario). European scale forest resource projections were made for 28 countries covering 131.7 million ha of forest under two management scenarios for the period until 2050.The results showed that net annual increments in stemwood of European forests under climate change will further increase with an additional 0.9 m3 ha−1 y−1 in 2030 compared to the ongoing increase under a current climate scenario, i.e. an extra 18% increase. After 2030 the extra increment increase is reduced to 0.79 m3 ha−1 y−1 in 2050. Under climate change, absolute net annual increments will increase from the present 4.95, on average for Europe, to 5.93 m3 ha−1 y−1 in 2025. After 2025, increments in all scenarios start to decline owing to ageing of the forest and the high growing stocks being reached.The results of the present study are surrounded by large uncertainties. These uncertainties are caused by unknown emissions in the future, unknown extent of climate change, uncertainty in process‐based models, uncertainty in inventory data, and uncertainty in inventory projection. Although the results are thus not conclusive, climate change may lead to extra felling opportunities in European forests of 87 million m3y−1. Because Europe's forests are intensively managed already, management may adapt to climate change relatively easily. However, this study also indicates that climate change may lead to a faster build‐up of growing stocks. That may create a less stable forest resource in terms of risks to storm damage.

Energy efficiency of large cardamom grown under Himalayan alder and natural forest

Energy efficiency of agroforestry systems of large cardamom grown under N2-fixing Himalayan alder (alder-cardamom) and natural forest (forest-cardamom) was studied in the Sikkim Himalaya. Large cardamom (Amomum subulatum), the most important perennial cash crop of the region, is widely cultivated with Himalayan alder (Alnus nepalensis) as shade tree. Energy fixation, storage, net allocation in agronomic yield, and heat release and exit from the system were respectively 1.57, 1.44, 2.24 and 2.22 times higher in the alder-cardamom compared to the forest-cardamom system. Energy conversion efficiency and net ecosystem energy increment were also higher in the alder-cardamom than the forest-cardamom system. Energy fixation efficiency and energy conversion efficiency of large cardamom increased under the influence of Himalayan alder. Energy efficiency in N2-fixation of Himalayan alder was also high (67.5 g N2 fixed 104 kJ-1 energy). Quantum and flux of energy increased in the alder-cardamom compared to the forest-cardamom system that optimized the production potential of the cash crop under the influence of the Himalayan alder. Climatic sympatry of the large cardamom and Himalayan alder, and their synergetic energy efficiency makes this association ecologically and economically viable for the mountain regions.

The Value of a Baseline Caries Risk Assessment Model in the Primary Dentition for the Prediction of Caries Incidence in the Permanent Dentition

To establish a reliable screening method for caries prediction and to identify predominant risk factors, this study tested whether a cross–sectional caries risk model assessed at age 7 could be used to predict future caries onset in the permanent first molars at age 10 in 3,303 children born in 1989. As prediction variables, assessing the believed risk, baseline data at age 7 on oral health status, oral hygiene level, oral health behaviour and sociodemographic factors were used. The real risk, based on data collected for the first permanent molars during the follow–up, was assessed by different approaches. Cumulative incidence during the 3–year observation period was 31.6%, ranging from 22.4% in the believed low–risk group to 43.2% in the believed high–risk group. A stepwise logistic regression analysis was performed with net caries increment as outcome measure, adjusted for the real time at risk, using eruption times. Baseline dmfs and occlusal and buccal plaque indices were highly significant for having a high caries increment in permanent first molars with respective odds ratios of 1.07, 1.43 and 1.35. Brushing less than once a day and the daily use of sugar–containing drinks between meals were confirmed as risk factors (OR 2.43 and 1.25, respectively). The logistic regression analysis provided a sensitivity of 59–66% and a specificity of 65.7–72.8%, which indicates that the risk marker did not have an important predictive power. None of the socio–demographic and behavioural variables had enough predictive power at community level to be useful for identifying caries susceptible children. Even the power of dmfs at baseline must be considered modest.