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Soil microbes are both drivers and contributors of soil organic C (SOC) dynamics. However, information on how the multiple co-occurring environmental changes affecting microbial community and residues is unclear. Here, we measured phospholipid fatty acids and amino sugars (ASs) to explore how soil microbial community and residues changed under soil warming, throughfall reduction, root exclusion and their interactions in a natural deciduous broad-leaved oak forest. Soil warming significantly increased the Gram-positive to Gram-negative bacteria (G+/G−) ratio, and its interaction with root exclusion significantly reduced fungi-to-bacteria (F/B) ratio but stimulated the contributions of ASs to SOC (AS/SOC). Throughfall reduction also marginally increased G+/G− and AS/SOC, and suppressed F/B ratio. However, no interactive effects of soil warming and throughfall reduction on soil microbial community and residues were observed. Light fraction organic C and inorganic nitrogen were the key drivers in regulating the variation in the microbial community structure, and SOC was the controlling factor of microbial residue accumulations. Hence, soil C quality instead of water dominates the responses of microbial community structure and residues contribution to SOC to soil warming. Our results highlight the importance of soil substrate quality when predicting the terrestrial climate-C feedback.

Himalayan forests are dominated by different species of oaks ( Quercus spp.) at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7), saplings (3–10), and seedlings (2–6). Seedling and sapling densities (Ind/ha) varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees), from 0.93 to 3.18 (saplings), and from 0.68 to 2.26 (seedlings). Total basal area (m 2 /ha) of trees and saplings was 2.2–87.07 m 2 /ha and 0.20–2.24 m 2 /ha, respectively, whereas that of seedlings varied from 299 cm 2 /ha to 8,177 cm 2 /ha. Maximum tree species (20–80%) had “good” regeneration. Quercus floribunda , the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

Ant assemblages in the soil have been studied at eight forest sites (4 oak forest sites, and 4 pine forest sites) in four study areas (1 seminatural area, and 3 industrialized areas) in South Korea for 6 years from 2002 to 2010. Soil cores and Tullgren funnel were used for the ant survey. Ant surveys were carried out once per year in autumn (from late September to mid-October). The soil pH was lower in the industrialized than in the seminatural area, showing the acidified soils in the industrialized areas. However, the soil acidification did not influence the ant assemblages. The results from the nonmetric multidimensional scaling ordination and from the community temperature index values indicate that temperature is a key determinant for structures of the soil ant assemblages. The ant assemblages were not different according to the forest types (oak forests vs. pine forests). Occurrence of ant species varied greatly among years, indicating that more replicates and advanced sampling method are needed for the monitoring of the soil ant assemblages.

ResumenLas cañadas de Coatepec Harinas, ubicadas al sur del Nevado de Toluca, son de interés para la conservación por su integridad biológica. En este estudio se presenta la composición de Scarabaeidae, Geotrupidae, Hybosoridae, Trogidae y Silphidae, además se analizan aspectos como abundancia, riqueza, diversidad y estacionalidad. Esta información servirá para el desarrollo de estudios comparativos posteriores realizados fuera de las cañadas. Los muestreos fueron mensuales durante un año con trampas tipo NTP-80 cebadas con calamar, en un bosque de encino con elementos de mesófilo de montaña. Se obtuvieron 1,513 individuos pertenecientes a 9 especies y 8 géneros. Silphidae (94.3%) fue la familia más abundante, seguida por Scarabaeidae (4.7%), ambas con 3 especies cada una; las restantes, una especie y menos de 10 ejemplares. Nicrophorus mexicanus Matthews, 1888 (Silphidae), Nicrophorus olidus Matthews, 1888 (Silphidae), Oxelytrum discicolle (Brullè, 1840) (Silphidae) y Oniticellus rhinocerulus Bates, 1889 (Scarabaeidae) agruparon el 99%. Germarostes Paulian, 1982 (Hybosoridae) se registró por primera vez para el Estado de México. La estacionalidad fue marcada: el 87.5% de la abundancia y las 9 especies obtenidas se registraron en las lluvias. La diversidad y la cobertura de la vegetación, así como la presencia de arroyos, propiciaron condiciones favorables para las 4 especies más abundantes.AbstractThe glens of Coatepec Harinas in the southern part of Nevado de Toluca are of conservation concern because of their biological integrity. This study reveals the composition of the Scarabaeidae, Geotrupidae, Hybosoridae, Trogidae and Silphidae of the Coatepec Harinas’ glens, and analyzes their abundance, species richness, diversity and seasonality. Such information can be used for further comparative studies conducted outside the glens. Monthly samples were obtained during a year using traps type NTP-80 baited with squid in an oak forest with some elements of cloud forest. A total amount of 1,513 individuals belonging to 9 species and 8 genera were collected. Silphidae (94.3%) was the most abundant family, followed by Scarabaeidae (4.7%), both of which had 3 species each; the remaining families had 1 species and less than 10 specimens. Moreover, Nicrophorus mexicanus Matthews, 1888 (Silphidae), Nicrophorus olidus Matthews, 1888 (Silphidae), Oxelytrum discicolle (Brullè, 1840) (Silphidae) and Oniticellus rhinocerulus Bates, 1889 (Scarabaeidae) grouped together 99% of individuals. Germarostes Paulian, 1982 (Hybosoridae) was recorded for the first time in the Estado de México. The seasonality was evident, 87.5% of the abundance and the 9 species were collected during the rainy season. The diversity of plants and tree canopy cover, as well as the presence of the stream, propitiated favorable conditions for the 4 most abundant species.

ResumenPresentamos los primeros registros de jaguar Panthera onca (Carnivora: Felidae) para el Parque Nacional Cumbres de Monterrey, Nuevo León, México. Entre los años 2013 a 2015 se colocaron cámaras trampa en los bosques templados del parque. Se obtuvieron 15 fotografías y 7 vídeos de varios individuos de la especie, que evidencian la presencia de una población dentro del parque nacional y que representa la población residente de jaguares más al norte de su área de distribución, por la vertiente del golfo de México. Por esta razón resulta necesario fortalecer acciones de protección ambiental para asegurar la conservación de esta población como: promover el pago de servicios ambientales, implementar el pago del seguro ganadero, capacitar a comités de vigilancia comunitarios y atender las denuncias sobre conflictos por depredación de ganado doméstico en esta área.AbstractWe present the first records of jaguar (Panthera onca) in Cumbres de Monterrey National Park, Nuevo León, Mexico. We placed remote cameras between 2013 and 2015 in oak forest habitats of the Park and obtained 15 pictures and 7 videos of 4 different individuals of the species. Our results constitute the first evidence of a resident population of jaguars in this protected area and the northernmost population of the species along the Gulf of Mexico. Strenthenging of conservation measures such as environmental services compensation, livestock compensation programs, conflict management and law enforcement are needed to protect this jaguar population.

Vegetation, forest floor, and soils were resampled at a mixed oak site in eastern Tennessee that had been subjected to stem only (SOH), whole-tree harvest (WTH), and no harvest (REF) 33 years previously. Although differences between harvest treatments were not statistically significant (P < 0.05), average diameter, height, basal area and biomass were 8–18% lower in the WTH than in the SOH treatment 33 years after harvest whereas they differed by 2% 15 years after harvest. In contrast to results 15 years post-harvest, total forest floor mass and nutrient contents were twofold greater in the WTH than in the SOH treatment at 33 years post-harvest, due largely to differences in Oa horizon mass. Soil total C concentrations increased significantly (P < 0.05) over the first 15 years post-harvest in both harvest treatments. Decreases in soil C between 15 and 33 years post-harvest were not statistically significant. Soil total N increased significantly in both harvest treatments over the first 15 years post-harvest. Consistent decreases in soil total N occurred in the WTH treatment between years 15 and 33 post-harvest that bordered on statistical significance whereas total N was stable over that time period in the SOH treatment. The increases and decreases in soil N content cannot be explained by any known processes of N inputs or outputs. Harvest treatment effects on both Ca2+ and Mg2+ observed at 15 years post-harvest are still observable and significant at 33 years post-harvest, although decreases between 15 and 33 years were found. Treatment effects and changes in soil exchangeable Ca2+ and Mg2+ are consistent with known inputs from decomposing logging residues, inputs from atmospheric deposition, and increments in forest floor and vegetation. No treatment effects were found for soil extractable P, but steady decreases over time were found. No treatment or time effects were found for soil exchangeable K+.

Phorophytes are assumed to act as facilitators for epiphytes, but empirical evidence indicates that they also act as amensalists. While few epiphytes can colonize most phorophytes, some epiphytes (such as orchids) appear in few phorophytes and/or have low population sizes, suggesting that are strongly phorophyte-limited. We assume that phorophyte type must determine the structure of the interaction network between epiphytes and phorophytes. In order to identify phorophyte type, we studied their distribution of epiphytes and, using two methods for measuring interaction intensity (raw and standardized data), analyzed the structure of the epiphyte-phorophyte interaction network. We quantified and identified all of the epiphytes and their phorophytes in all of the woody plants (diameter at breath height ≥ 5 cm) found in five 0.1 ha transects (10 × 100 m) in an oak forest of central Mexico. Acacia farnesiana and Bursera copallifera were the preferred phorophytes with greater epiphyte loads than would be expected by chance, while Quercus magnoliifolia and Q. candicans were limiting, with less epiphytes than would be expected by chance. In the network analyses, the preferred phorophytes concentrated interactions. These included B. copallifera, which, despite being infrequent, had the highest intensity of interaction with the most abundant epiphyte (Viridantha atroviridipetala: Bromeliaceae), while the most abundant phorophyte (Q. magnoliifolia) had low interaction intensity. This study reinforces the increasing evidence showing that epiphytes can be phorophyte-limited and shows that the type and importance of phorophytes within the interaction network is not determined by their abundance.

[EN] Mediterranean drylands are often nutrient poor, but parameter requirements of forest ecosystem models are usually high. Therefore, there is a need for developing parsimonious nutrients models. In that sense, this study aims to contribute to a better understanding and modelling of the hydrological and biogeochemical (carbon and nitrogen) cycles and their interactions in semiarid conditions and to test the capability of a new parsimonious model to satisfactorily reproduce them. The proposed model (TETIS-CN) and two additional widely used models were implemented in a Quercus ilex forest, and no noteworthy differences were found. Results suggest that: (1) it is important to include carbon observations in the calibration process and to consider all the existing vegetation species in the simulation; (2) a fixed daily potential uptake may not be appropriate to reproduce plant nitrogen uptake; and (3) TETIS-CN, with a lower number of parameters, proved an acceptable tool., This work was supported by the Spanish Ministry of Science and Innovation through the research projects: TETISMED (CGL2014-58127-C3-3-R), SILWAMED (CGL2014-58127-C3-2-R), CEHYRFO-MED (CGL2017-86839-C3-2-R) and TETISCHANGE (RTI2018-093717-B100), and by the project LIFE17CCA/ES/000063 RESILIENTFORESTS.

Little is known about the effects that oak forest regeneration treatments consisting of a combination of shelterwood harvesting and prescribed fire have on bats, despite increasing use of these treatments. We quantified changes in bat activity levels in relation to oak forest regeneration treatments consisting of harvesting at 50% and 70% retention levels and prescribed fire in two upland Appalachian hardwood forests in Ohio. We monitored bat activity immediately post-harvest, three growing seasons post-harvest, and after application of prescribed fire to harvested stands before the fourth growing season. Total bat activity levels were higher in thinned and thinned and burned treatments than in unthinned controls in all years, but did not differ between harvest treatment levels immediately post-harvest, three growing seasons post-harvest, or between harvest treatment levels within years. Total bat activity post-prescribed fire changed only in the 50% retention harvest treatment blocks, wherein activity decreased. Activity levels of big brown (Eptesicus fuscus) bats were greater in harvested treatment blocks than controls in all years. Activity levels of eastern red (Lasiurus borealis), and Myotis spp. and tri-colored (Perimyotis subflavus) collectively did not differ among treatment blocks post-fire, but were greater in harvested treatment blocks than controls three growing seasons post-harvest. Community composition was strongly related to vegetation volume, with eastern red bats and Myotis and tri-colored bats displaying positive relationships with clutter in low height strata, and big brown bats displaying a negative relationship with clutter in all height strata. The positive relationship between eastern red and Myotis and tri-colored bats and clutter in low height strata may explain why activity levels of these species decreased post-prescribed fire. Our study suggests that the harvesting component of oak forest regeneration treatments may benefit bats for several years, and that while bat activity levels may decline post-prescribed fire, overall activity levels are nonetheless greater than in unthinned areas.

An accurate map of forest types is important for proper usage and management of forestry resources. Medium resolution satellite images (e.g., Landsat) have been widely used for forest type mapping because they are able to cover large areas more efficiently than the traditional forest inventory. However, the results of a detailed forest type classification based on these images are still not satisfactory. To improve forest mapping accuracy, this study proposed an operational method to get detailed forest types from dense Landsat time-series incorporating with or without topographic information provided by DEM. This method integrated a feature selection and a training-sample-adding procedure into a hierarchical classification framework. The proposed method has been tested in Vinton County of southeastern Ohio. The detailed forest types include pine forest, oak forest, and mixed-mesophytic forest. The proposed method was trained and validated using ground samples from field plots. The three forest types were classified with an overall accuracy of 90.52% using dense Landsat time-series, while topographic information can only slightly improve the accuracy to 92.63%. Moreover, the comparison between results of using Landsat time-series and a single image reveals that time-series data can largely improve the accuracy of forest type mapping, indicating the importance of phenological information contained in multi-seasonal images for discriminating different forest types. Thanks to zero cost of all input remotely sensed datasets and ease of implementation, this approach has the potential to be applied to map forest types at regional or global scales.

a b s t r a c t A long-term experimental drought to simulate future expected climatic conditions for Mediterranean forests, a 15% decrease in soil moisture for the following decades, was conducted in a holm oak forest since 1999. Net photosynthetic rate, stomatal conductance and leaf water potential were measured from 1999 to 2013 in Quercus ilex and Phillyrea latifolia, two co-dominant species of this forest. These measurements were performed in four plots, two of them received the drought treatment and the two other plots were control plots. The three studied variables decreased with increases in VPD and decreases in soil moisture in both species, but the decrease of leaf water potential during summer drought was larger in P. latifolia, whereas Q. ilex reached higher net photosynthetic rates and stomatal conductance values during rainy periods than P. latifolia. The drought treatment decreased ca. 8% the net photosynthetic rates during the overall studied period in both Q. ilex and P. latifolia, whereas there were just non-significant trends toward a decrease in leaf water potential and stomatal conductance induced by drought treatment. Future drier climate may lead to a decrease in the carbon balance of Mediterranean species, and some shrub species well resistant to drought could gain competitive advantage relative to Q. ilex, currently the dominant species of this forest.

Respiratory carbon losses from a mixed oak forest ecosystem following experimental manipulations were examined for their magnitudes and biophysical regulations. To quantify these losses, respiration measurements from chamber-based ecosystem components of sapwood, snags, down-logs, and soil, using chamber-based methods, were collected from experimental stands 8 yr after the manipulations of: non-harvest (NHM), uneven-aged (UAM), and even-aged (EAM) managements. Temperature and respiration relationships ( R = R 0 × e β × T ) were used to estimate annual ecosystem respiration. The annual respiration rates were 1684 g C m −2 yr −1 in the NHM, 1787 g C m −2 yr −1 in the UAM, and 1231 g C m −2 yr −1 in the EAM stands. Harvesting reduced annual ecosystem respiration in the EAM stands by 28% compared to the NHM stands. Soil respiration was the largest component and contributed from 72% to 85% of the total respiration. The sapwood and leaf respiration were the second largest components of ecosystem respiration in both NHM and UAM stands, but down-logs were the second largest component in the EAM stands. Harvest significantly affected ecosystem respiration, with intensity driving changes in component respiration.

Soils in a succession row of forest re-growth in the European part of Russia were studied after abandonment of arable land use (7 up to 45 years), and compared to soils of secondary (80–100 yrs), of old-age (>100 yrs) and of mature (450 yrs) coniferous and deciduous forest sites. At each site, two top layers of the podzolic soils were analyzed for microbial biomass ( C mic ), basal CO 2 respiration activity (BR), metabolic quotient ( q CO 2 ), C mic / C org and fungal/bacterial ratios. In the uppermost soil layer, C mic increased significantly (149, 187, 245, 502, 759, and 755 μg C mic g −1 soil) in the succession row of arable, young fallow, young forests (20 and 45 yrs), and secondary and mature forests, as it was found for BR (0.40, 0.55, 0.76, 1.67, 2.52, 2.34 μg CO 2 –C g −1 h −1 soil), respectively. Both C mic and BR were higher in the uppermost soil layer compared to the lower one. In soils of old-age spruce and oak forest, C mic , BR and the C mic / C org ratio were significantly higher compared to the soils of the succession row, while q CO 2 was lower. The fungal contribution to total substrate-induced respiration was 58–74%, with a tendency to increase in mature or old-age forests, as compared to young forests and arable soil. Thus, we found evidence that forest succession on abandoned arable sites in European Russia promotes soil microbial biomass and activity up to a level of mature forests, combined with shifts toward a fungal dominated community.

Aerial sketch-map surveys and systematic forest field inventories may be used separately or in combination to indicate the status of regional forest health. During recent decades, aerially conducted sketch-maps of forest damage and forest inventories have been used to assess oak (Quercus spp) forest health across a 24-state region spanning the northern U.S. In order to more fully inform the monitoring of oak forest health and integrate these independent datasets, the effect of the quality, timing, and repeated sampling of aerial data on correlations with field-based oak forest assessments was assessed. Study results indicated that aerial damage surveys were weakly correlated with indicators of oak forest sustainability (e.g., oak seedlings and saplings), but more highly correlated with overstory attributes such as tree mortality and standing dead. The highest correlations between aerial damage surveys and oak mortality/standing dead were found when the time between the aerial survey and subsequent forest inventory was 4–6 years. Aerial surveys may have their greatest efficacy in supplementing field inventories of oak forest health when they are conducted in a high quality manner with bi-annual or longer remeasurement periods (due to rare pest damage events).

Climate change will increase the frequency and the intensity of droughts in the Mediterranean region, likely reducing growth and increasing mortality of holm oaks (Quercus ilex), one of the most abundant species of Mediterranean forests. In water-limited systems such as those of the Mediterranean, carbon allocation patterns strongly favour belowground accumulation, especially in large subterranean structures called lignotubers. The resilience of these forests depends largely on the replenishment rate of these carbon reserves after disturbances. An experimental thinning, with two intensities (removal of 40% and 80% of basal area), was performed in 1992 in a holm oak forest at the Prades Experimental Complex of Catchments (NE Spain). In 2002, a second thinning was carried out in subplots within the former experimental 0.5 ha plots. Samples from the lignotubers of holm oak trees were analyzed for starch, and both mobile and immobile chemical components, in order to assess the resilience of holm oaks to repeated disturbances. Our results show that after 10 years, starch stocks in the lignotubers have only recovered to half their former values. Removing 40% of the basal area instead of 80% is suggested to be the better managing option for this kind of forests.

Soil testate amoebae are cosmopolitan and abundant protozoa, and accumulate silica for reproduction. Their effect on the terrestrial silica cycle, however, has not been quantitatively determined. We found that testate amoebae consumed 55% of silica absorbed by microbes in the incubation experiment. We estimated amoeban biosilica using our present data and published data. Although biosilica preserved by living testate amoebae was as small as 0.45–1.57 kg SiO 2 ha − 1 , annual biosilicification in various forest soils was estimated to range from 10 to 227 kg SiO 2 ha − 1 yr − 1 . We concluded that testate amoebae have a high potential as silica consumers and suppliers, and play a role comparable to that of higher plants in the terrestrial silica cycle.

New data are provided on the history of Holocene vegetation based on pollen records from a coastal sequence on the Cantabrian coast. A core with a continuous record corresponding to a complex sequence reflecting upward shallowing was studied, and two 14 C dates of 6180F40 (7030 cal.) yr BP and 2610F70 (2775 cal.) yr BP were obtained. The pollen study highlights the development in the area of an oak forest with Corylus, the presence of an interesting thermophilous floral assemblage and alder forests that spread around 3000 years ago. The latter appears to be related to the availability of large areas of territory close to the Villaviciosa Estuary main channel and to a high phreatic zone. It is interpreted as a response to autocyclic sedimentary discontinuity (channel displacement) rather than as an episode of sea-level fall. D 2006 Published by Elsevier B.V.

A field trial was conducted to monitor aerially applied pesticide movement above an oak forest in a near-neutral planetary boundary layer using a lidar system. A 36.6-m tower, instrumented at six levels with fast response micrometeorological sensors, recorded wind, turbulence, and temperature profiles during the spray runs. The micrometeorology data was used to drive two spray drift models for a comparison of drift estimates. The models used in this study were USDA Forest Service Cramer-Barry-Grim (FSCBG), an industry standard engineering model, and University of Connecticut Spray Transport (UCST), a heavy particle Lagrangian transport model. Over five spray runs, the FSCBG model predicted

Mathematical programming is one quantitative technique that can be used for strategic and tactical natural resources planning. It has been extensively used both at private and public forest planning levels. Nevertheless, most applications concentrate on modelling of systems involving timber harvesting. This paper focuses on cork oak ( Quercus suber L.) forest management. It summarizes the methodology to follow in order to generate information needed for modelling purposes. It formulates a cork oak forest management problem using a linear programming model. A case study is used to illustrate the procedure used. The results of the research on a modelling approach to cork oak forest management for an area extending over 5272 ha in the Portuguese submediterranean ecological region are presented. Extensions to this study are identified.

Concentrations of α-pinene, β-pinene and limonene were determined as two or three point profiles above the Mediterranean pine/oak forest at Castelporziano, Italy. Based on these, as well as on micrometecrological data, the fluxes of these compounds were estimated using the modified Bowen-ratio method and a log-profile fit. The accuracy of the calculated fluxes was estimated, resulting in errors around 50%, which were mainly produced by the relatively small concentration gradients observed. The dependence of emission fluxes on surface temperature was interpolated by three equations of the form F(T) = Fsexp(β·(T − TS)) for the three compounds. The three resulting temperature exponents β were significantly greater than the value for monoterpenes given by Guenther et al. (1993, J. Geophysical Research 18, 12,609–12,617). It is also greater than the corresponding value derived by Bertin et al. (1997, Atmospheric; Environment) from the isoprene model of Guenther et al. (1993, J. Geophysical Research 18, 12,609–12,617).

The elemental composition of wood varies according to the genotype and ecological conditions of plant development. Inorganic elements of wood are preserved in charcoal. Elemental composition analyses of olive wood combined with a multivariate statistical treatment show that wild and cultivated trees and their bioclimatic environments can be distinguished (thermomediterranean and mesomediterranean stages). The elemental composition of some olive charcoal from two archaeological sites in Spain is analysed. The bioclimatic and taxonomic information obtained from archaeological charcoal analyses records the anthropogenic processes interpreted as the transition from a mesophilous phase (Cardial Neolithic) to a thermophilous phase (Roman Age), correlated with the gradual replacement of the former mixed oak forest by the “matorral”. Finally, these results address the question of whether the cultivation of olive trees had occurred in Spain by the Neolithic.

The measurements of all forms of atmospheric fallout, migration of heavy metals (HM) in soil water, in soluble and suspended form, and the stream output from a small watershed were examined. The geochemistry of Pb, Zn, Cd and Cu in a polluted ecosystem of oak forests has been studied. The process of HM fixation is concurrent with the process of their migration in the more energy saturated soil-plant part of an ecosystem. The main factor of HM migration is water-soluble organic compounds. The basic pool of accumulation of HM is a thin layer of mull; plants support a high HM load.

Above-ground net primary productivity (ANPP) and potential nitrogen (N) mineralization were measured in four forest types along a soil fertility gradient in eastern Kentucky to test the hypothesis that ANPP in the mixed mesophytic forest region is related to both species composition and mineralizable N. N mineralization differed significantly among the four forest types, with the lowest values occurring on sites containing oak forest and the highest rates occurring on sites containing a mixed mesophytic forest. However, ANPP did not differ among forest types, and was unrelated to mineralizable N. ANPP averaged 6306 kg ha −1 year −1 , of which 56% was woody production and 44% was above-ground litter production. The poor relationship between ANPP and site fertility may reflect differential patterns of nutrient use efficiency among the deciduous species which make up the vegetation gradients of eastern Kentucky.

Nocturnal cold air drainage was examined in corn and oak canopies, and over a bare field on a hillside in Storrs, Connecticut. Smoke tracers, and vertical profiles of wind and temperature showed drainage flow development and persistence to be markedly affected by surface cover. In corn, the drainage flow maximums were in the order of 1 m s −1 above the canopy and 0.4 m s −1 inside the canopy. In the leafed hardwood forest, drainage flow only developed above the canopy. Only ground drainage flows developed in the forest during the leafless phase. Cold air drainage flows within the corn and leafless oak canopies were often maintained during periods of high local windspeeds (> 5 m s −1 ) when drainage flow above the canopies and over bare ground was no longer apparent. Measured flow rates were compared to predicted rates from models developed by Fleagle, and Petkovsek and Hocevar. We found the form assumed for the frictional force in these models inadequate for use with katabatic air flows in tall roughness elements. In some cases the Cionco canopy flow model, modified for stability, simulated the within canopy flows.

Pollen diagrams have been obtained from three places in Greece. The one from Limni Kopais in southern mainland Greece covers the last part of the Wurm glaciation and most of the Holocene and shows that at the end of the Wurm the developing oak woodland responded to a climatic oscillation, comparable with the Allerod oscillation in northwest Europe, and was later seriously reduced during Final Neolithic times. A diagram from the uppermost peats of Tenaghi Philippon shows that the area was forested until at least the time of Christ and another from Gravouna, further east, which covers the last two thousand years or so, shows the change from oak forest to the present open shiblyak vegetation of the region. Where possible, correlations have been made with pollen zones of other authors who have published diagrams from the country.

The Mamora cork forest (central Morocco), located on sandy soils in the Moroccan coastal plain where the climate is semiarid (annual rainfall, depending on the zone, in the range 400–600 mm) with very dry summers and temperate-warm winters, covers 60 000 ha and is the largest cork forest in the world. The trees in this forest are vital in that they protect and improve the pasture growing beneath them, as well as producing abundant fruit that can be eaten by livestock, and foliage which can serve as emergency feed. This, combined with its special geographic/regional location, makes Mamora an important pasturing area. It also produces some 40% of Moroccan cork and is therefore of great sylvicultural and industrial significance also, making it a sylvo-pastoral area of major economic and social importance at both regional and national levels. In view of its spatial and social peculiarities, namely its division into large tribal areas (communes) that are in turn divided into tribal group sub-areas, and also of the employment and training needs of its labor force, the utilization of the forest needs to be re-organized in accordance with a new spatial structure to ensure continuity of employment, raise the vocational skills of its labor force, and improve its pastures through the programming of new sylvo-pastoral measures appropriately distributed over this structure and also over the course of the year. Furthermore, the present shrinkage of the forest calls for a cork re-forestation program. Since this means placing large areas off-limits to pasturing, pastures must be improved to compensate for the feed resources lost. The combined forestry and pasture function of the operations now being proposed and programmed will ensure a return for them that they would not obtain if they concentrated on one function only. To sum up: on the basis of a study of the ecological, social and geographic environment of the Mamora cork forest, the introduction of a new sylvo-pastoral system is proposed that would be based on a new spatial organization which, while respecting the existing ecological, pasturing and cork-production constraints, would provide better and more permanent rural employment and permit higher sylvo-pastoral production under conditions compatible with long-term conservation of the system.

A multi-layer 'K-theory' model for gaseous deposition to a deciduous forest is described and discussed. The model incorporates realistic physiological concepts to improve upon earlier multi-layer models found in the literature. Computations of deposition fluxes and velocities are most sensitive to variations in parameters relating to stomatal resistance. The model computations of deposition velocities are less sensitive to aerodynamic parameters since the canopy resistance of a deciduous forest is generally much greater than the aerodynamic resistance. Model computations of SO2 flux and deposition velocities are tested against deposition measurements made over a deciduous forest; these computations are not significantly different from measured values. Estimates of deposition fluxes, computed with multi-layer model, improve upon those values estimated with a "big-leaf" model. Key word index: Dry deposition, canopy-atmosphere interactions, K-theory model, micrometeorology.

The albedo of an oak forest was measured on 16 days throughout the year. Growing-season albedo ranged from 16 to 18% with variations due to cloud conditions. Autumn albedos did not increase with leaf color changes and until leaf fall was nearly complete remained similar to growing season values. Dormant season albedo was 12 to 14% without snow and 25 to 30% with snow on the ground. The effects of zenith angle on albedo were noticeable during a day, but these albedo changes were much more pronounced during the growing than in the dormant season. The measurements also suggested that the forest was a diffuse reflector.

When the presettlement deciduous forest, as described from land-survey notes of 1854–1860, is compared with relict forest stands of today, it is clear that mesic succession has taken place. The “Big Woods”, dominated by Acer and Tilia , has developed from a forest dominated by Ulmus and Quercus with some Tilia and Acer . Two pollen diagrams spanning the past 1,000 years show that this succession was initiated several hundred years before settlement. Three pollen diagrams from the adjacent oak forest suggest a concurrent succession from Quercus savanna, as well as a later increase in mesic elements at the time of settlement. An area that was oak barrens (a type of Quercus savanna) at the time of settlement, now has relict stands of oak forest; the two pollen diagrams from this area suggest the formation of oak forest since settlement. The mesic successions are probably a culmination of a long-term change toward a cooler and moister climate, but a postulated decrease in Indian populations and fires after European contact about 1650 and before settlement could have accelerated the vegetation successions.

Summary The results of pollen analyses from six bogs at various altitudes north and south of the Passo di Lucomagno are discussed: 1. The Valle del Lucomagno became free of ice in the Bolling period at the latest, whilst the slope terraces of Brigels and Obersaxen (Vorderrhein Valley) did so in the Allerod period. 2. It was possible to confirm once more the existence of a pre-boreal cold phase (Piottino fluctuation) in four different places. This period turned out to be identical to the Daun phase, and its termination could be placed between 7500 and 7000 B.C. by three C14-datings. 3. In the Ticino the existence of a marked Juniperus shrub-phase during the Bolling period has been proved for the first time. 4. In the Allerod period, a belt of Larix-Pinus cembra together with Betula and Pinus silvestris/mugo established itself at medium altitudes. With the pre-boreal climatic improvement, the Larix-Pinus cembra belt moved upwards and at the same time Ericaceae migrated into the area. During the Atlanticum the belt was narrowed by Picea advancing from the lower slopes, and finally it became almost extinguished by the clearing for Alpine pastures. 5. The existence, during early post-glacial times, of mixed Tilia forests above the upper limits of the present extent was proved by the finding of fossil fruits. 6. For the post-glacial colonization of the northern slopes of the Alps, the low-lying Passo di Lucomagno (1916 m) was an important migration route for trees and shrubs. As regards Abies and Alnus incana this migration is a proven fact, whilst for mixed oak forest and Acer it must be considered a probability. 7. During the middle Sub-Atlanticum period, Fagus was considerably more established in the Vorderrhein Valley than it is today.

The Postglacial history of the vegetation of southern Dalmatia is studied by means of pollen analysis of the lake deposits of the Malo Jezero on the island Mljet. The pollen diagrams reflect four forest periods: 1. (1) Period A: period of deciduous oak forest. About 7,000 (beginning of sedimentation)-5,600 B.C. 2. (2) Period B: Juniperus-Phillyrea period. Beginning of eu-mediterranean climate conditions. 5,600-4,300 B.C. 3. (3) Period C: Quercus ilex period. 4,300-about 200 B.C. 4. (4) Period D: Pinus-Quercus ilex period. Sediments of the last 1,900−2,000 years are lacking.