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Pine Plantations (pine + plantation)
Selected AbstractsEFFECTS OF CONTROLLED DRAINAGE ON STORM EVENT HYDROLOGY IN A LOBLOLLY PINE PLANTATION,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2000D. M. Amatya ABSTRACT: A paired watershed approach was utilized to study the effects of three water management regimes on storm event hydrology in three experimental watersheds in a drained loblolly pine (Pinus taeda L.) plantation in eastern North Carolina. The regimes were: (1) conventional drainage, (2) controlled drainage (CD) to reduce outflows during spring fish recruitment, and (3) controlled drainage to reduce outflows and conserve water during the growing season. Data from two pit-treatment years and three years of CD treatment with raised weirs at the watershed outlet are presented. CD treatment resulted in rises in water table elevations during the summer. But the rises were small and short-lived due to increased evapotranspiration (ET) rates as compared to the spring treatment with lower ET demands. CD treatment had no effect on water tables deeper than 1.3 m. CD treatments, however, significantly (,= 0.05) reduced the stoning outflows for all events, and peak outflow rates for most of the events depending upon the outlet weir level. In some events, flows did not occur at all in watersheds with CD. When event outflows occurred, duration of the event was sharply reduced because of reduced effective ditch depth. Water table depth at the start of an event influenced the effect of CD treatment on storm event hydrology. [source] Assemblages of soil macrofauna across a Scottish land-use intensification gradient: influences of habitat quality, heterogeneity and areaJOURNAL OF APPLIED ECOLOGY, Issue 6 2005PAUL EGGLETON Summary 1Land-use intensification strongly influences biodiversity by altering habitat heterogeneity, the distribution of habitat types and their extent. This study explores these effects within mixed semi-natural/agricultural mosaic habitats in Scotland, examining the effect of land-use intensification on the soil macrofauna at point (m2), landscape (km2) and regional (> 1 km2) scales. 2The soil macrofauna in six 1-km2 sampling areas (land-use units; LUU) were sampled using a combined hand-sorting and Winkler bag extraction technique. Within each LUU, 16 1-m2 samples were taken in each of 2 successive years. Each LUU had a mixture of land-use types, representing an agricultural intensification gradient. 3The following hypotheses were tested: (i) the study area sustains a number of distinct habitats as defined by soil macrofaunal composition; (ii) a greater number of restricted range species are found in semi-natural habitats; (iii) local (point) species density is related to habitat type; (iv) overall levels of species richness per habitat at regional scales are related to species-area effects; and (v) landscape-level species density is correlated with habitat heterogeneity. 4Initial analysis revealed five distinct habitat types: Caledonian forest (semi-natural pine forest), closed canopy woodland (pine plantation and broadleaved woodland), riparian habitats (wet woodland and grassland), pasture (improved grassland) and arable (crop fields). 5As hypothesized, the Caledonian habitat contained a greater number of restricted-range species than the other habitats. However, conifer plantations contained more restricted range species than expected, given their anthropogenic origin. Species density per m2 was most strongly affected by habitat type. At the regional level, the size of the species pool was correlated with the size of habitat areas. There were more species overall in LUU with greater habitat heterogeneity. 6Synthesis and applications. Caledonian pine forests have high species densities and contain species of conservation value. Mixed conifer plantations also appear to have a surprisingly high invertebrate conservation value. In contrast, intensively managed agricultural habitats have low species densities and conservation value. Generally, mixed land-use areas have higher species densities than single land-use areas. This emphasizes the need for careful management of forest systems within the matrix of agricultural habitats to maximize landscape diversity. [source] Enrichment planting does not improve tree restoration when compared with natural regeneration in a former pine plantation in Kibale National Park, UgandaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Patrick A. Omeja Abstract Given the high rates of deforestation and subsequent land abandonment, there are increasing calls to reforest degraded lands; however, many areas are in a state of arrested succession. Plantations can break arrested succession and the sale of timber can pay for restoration efforts. However, if the harvest damages native regeneration, it may be necessary to intervene with enrichment planting. Unfortunately, it is not clear when intervention is necessary. Here, we document the rate of biomass accumulation of planted seedlings relative to natural regeneration in a harvested plantation in Kibale National Park, Uganda. We established two 2-ha plots and in one, we planted 100 seedlings of each of four native species, and we monitored all tree regeneration in this area and the control plot. After 4 years, naturally regenerating trees were much taller, larger and more common than the planted seedlings. Species richness and two nonparametric estimators of richness were comparable between the plots. The cumulative biomass of planted seedlings accounted for 0.04% of the total above-ground tree biomass. The use of plantations facilitated the growth of indigenous trees, and enrichment planting subsequent to harvesting was not necessary to obtain a rich tree community with a large number of new recruits. Résumé Étant donné le rythme élevé de déforestation et, par la suite, d'abandon de terres, il y a des demandes croissantes pour repeupler les terrains dégradés; cependant, de nombreuses surfaces se trouvent dans un état de succession interrompu. Des plantations peuvent mettre fin à cette succession stoppée, et la vente de grumes peut financer les efforts de reforestation. Pourtant, si les prélèvements d'arbres endommagent la régénération naturelle, il peut être nécessaire d'intervenir avec des plantations d'appoint. Malheureusement, il n'est pas toujours facile de savoir quand une intervention est nécessaire. Nous documentons ici le taux d'accumulation de biomasse dans des jeunes arbres replantés par rapport à la régénération naturelle dans une plantation exploitée, à l'intérieur du Parc National de Kibale, en Ouganda. Nous avons établi deux parcelles de deux hectares et, dans une, nous avons repiqué 100 plants de chacune des quatre espèces natives. Nous avons ensuite suivi la régénération de tous les arbres dans cette parcelle et dans la parcelle témoin. Après quatre ans, les arbres provenant de la régénération naturelle étaient beaucoup plus grands, plus gros et plus abondants que les arbres replantés. La richesse en espèces et deux estimateurs nonparamétriques de la richesse étaient comparables dans les deux parcelles. La biomasse cumulée des jeunes arbres plantés comptait pour 0,04% de la biomasse aérienne totale des arbres. Le recours à des plantations a facilité la croissance d'arbres indigènes et la plantation d'appoint faisant suite à l'exploitation ne fut pas nécessaire pour obtenir une communauté d'arbres riche, avec un grand nombre de nouvelles recrues. [source] Coarse woody debris in Australian forest ecosystems: A reviewAUSTRAL ECOLOGY, Issue 8 2005GEMMA WOLDENDORP Abstract Coarse woody debris (CWD) is the standing and fallen dead wood in a forest and serves an important role in ecosystem functioning. There have been several studies that include estimates of CWD in Australian forests but little synthesis of these results. This paper presents findings from a literature review of CWD and fine litter quantities. Estimates of forest-floor CWD, snags and litter from the literature are presented for woodland, rainforest, open forest and tall open forest, pine plantation and native hardwood plantation. Mean mass of forest floor CWD in Australian native forests ranged from 19 t ha,1 in woodland to 134 t ha,1 in tall open forest. These values were generally within the range of those observed for similar ecosystems in other parts of the world. Quantities in tall open forests were found to be considerably higher than those observed for hardwood forests in North America, and more similar to the amounts reported for coniferous forests with large sized trees on the west coast of the USA and Canada. Mean proportion of total above-ground biomass as forest floor CWD was approximately 18% in open forests, 16% in tall open forests, 13% in rainforests, and 4% in eucalypt plantations. CWD can be high in exotic pine plantations when there are considerable quantities of residue from previous native forest stands. Mean snag biomass in Australian forests was generally lower than the US mean for snags in conifer forests and higher than hardwood forest. These results are of value for studies of carbon and nutrient stocks and dynamics, habitat values and fire hazards. [source] Patterns of Richness and Abundance in a Tropical African Leaf-litter Herpetofauna,BIOTROPICA, Issue 3 2001James R. Vonesh ABSTRACT I compared species richness and habitat correlates of leaf-litter herpetofaunal abundance in undisturbed and selectively logged forests, and an abandoned pine plantation in Kibale National Park, Uganda. I sampled 50 randomly located 25 m2 litter plots in each area during the wet and dry seasons in 1997. Ten anuran, five lizard, and three snake species were captured in plots over the study. Assemblage composition was most similar at logged and unlogged sites. The logged forest herpetofauna had higher species richness and abundance than the unlogged forest, but diversity was greater in the unlogged forest due to greater evenness. In contrast, the pine plantation site had the highest richness, abundance, and evenness of the three study sites, but species composition was distinct from the other areas. Herpetofaunal densities were significantly lower in all three areas during the dry season than in the wet season. During the dry season, soil moisture, litter mass, topography, shrub cover, and number of fallen logs were significant positive predictors of herpetofaunal presence in litter plots, but only soil moisture was significant in the wet season. The interaction of moisture and topography appears to be important in determining seasonal patterns of litter herpetofaunal distribution. Comparison of litter herpetofaunal studies across the tropics have shown that mid-elevation faunas generally support fewer species than lowland faunas. Compared with other tropical mid-elevation litter faunas, Kibale supports an intermediate number of species, but at lower densities than observed at any other mid-elevation site reported in the literature. [source] One Hundred Fifty Years of Change in Forest Bird Breeding Habitat: Estimates of Species DistributionsCONSERVATION BIOLOGY, Issue 6 2005LISA A. SCHULTE aptitud del hábitat; ecología aviar; ecología de paisaje; planificación de conservación Abstract:,Evaluating bird population trends requires baseline data. In North America the earliest population data available are those from the late 1960s. Forest conditions in the northern Great Lake states (U.S.A.), however, have undergone succession since the region was originally cut over around the turn of the twentieth century, and it is expected that bird populations have undergone concomitant change. We propose pre-Euro-American settlement as an alternative baseline for assessing changes in bird populations. We evaluated the amount, quality, and distribution of breeding bird habitat during the mid-1800s and early 1990s for three forest birds: the Pine Warbler (Dendroica pinus), Blackburnian Warbler (D. fusca), and Black-throated Green Warbler (D. virens). We constructed models of bird and habitat relationships based on literature review and regional data sets of bird abundance and applied these models to widely available vegetation data. Original public-land survey records represented historical habitat conditions, and a combination of forest inventory and national land-cover data represented current conditions. We assessed model robustness by comparing current habitat distribution to actual breeding bird locations from the Wisconsin Breeding Bird Atlas. The model showed little change in the overall amount of Pine Warbler habitat, whereas both the Blackburnian Warber and the Black-throated Green Warbler have experienced substantial habitat losses. For the species we examined, habitat quality has degraded since presettlement and the spatial distribution of habitat shifted among ecoregions, with range expansion accompanying forest incursion into previously open habitats or the replacement of native forests with pine plantations. Sources of habitat loss and degradation include loss of conifers and loss of large trees. Using widely available data sources in a habitat suitability model framework, our method provides a long-term analysis of change in bird habitat and a presettlement baseline for assessing current conservation priority. Resumen:,La evaluación de tendencias de las poblaciones de aves requiere de datos de referencia. En Norte América, los primeros datos disponibles de poblaciones son del final de la década de 1960. Sin embargo, las condiciones de los bosques en los estados de los Grandes Lagos (E.U.A.) han experimentado sucesión desde que la región fue talada en los inicios del siglo veinte, y se espera que las poblaciones de aves hayan experimentado cambios concomitantes. Proponemos que se considere al período previo a la colonización euro americana como referencia alternativa para evaluar los cambios en las poblaciones de aves. Evaluamos la cantidad, calidad y distribución del hábitat para reproducción de tres especies de aves de bosque (Dendroica pinus, D. fusca y D. virens) a mediados del siglo XIX e inicios del XX. Construimos modelos de las relaciones entre las aves y el hábitat con base en la literatura y conjuntos de datos de abundancia de aves y los aplicamos a los datos de vegetación ampliamente disponibles. Los registros topográficos de tierras públicas originales representaron las condiciones históricas del hábitat, y una combinación de datos del inventario forestal y de cobertura de suelo representaron las condiciones actuales. Evaluamos la robustez del modelo mediante la comparación de la distribución de hábitat actual con sitios de reproducción de aves registrados en el Wisconsin Breeding Bird Atlas. El modelo mostró poco cambio en la cantidad total de hábitat de Dendroica pinus, mientras que tanto D. fusca como D. virens han experimentado pérdidas sustanciales de hábitat. Para las especies examinadas, la calidad del hábitat se ha degradado desde antes de la colonización y la distribución espacial del hábitat cambió entre ecoregiones, con la expansión del rango acompañando la incursión de bosques en hábitats anteriormente abiertos o el reemplazo de bosques nativos con plantaciones de pinos. Las fuentes de pérdida y degradación de hábitats incluyen la pérdida de coníferas y de árboles grandes. Mediante la utilización de fuentes de datos ampliamente disponibles en un modelo de aptitud de hábitat, nuestro método proporciona un análisis a largo plazo de los cambios en el hábitat de aves y una referencia precolonización para evaluar prioridades de conservación actuales. [source] The fundamental and realized niche of the Monterey Pine aphid, Essigella californica (Essig) (Hemiptera: Aphididae): implications for managing softwood plantations in AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 4 2004Trudi N. Wharton ABSTRACT Essigella californica is a pine aphid native to western North America. In Australia, E. californica is considered an invasive pest that has the potential to cause severe economic loss to the Australian forestry industry. Two CLIMEX models were developed to predict the Australian and global distribution of E. californica under current climate conditions based upon the aphid's known North American distribution. The first model (model I) was fitted using the reasonably contiguous set of location records in North America that constituted the known range of E. californica, and excluded consideration of a single (reliable) location record of the aphid in southern Florida. The second model (model II) was fitted using all known records in North America. Model I indicated that the aphid would be climatically restricted to the temperate, Mediterranean and subtropical climatic regions of Australia. In northern Australia it would be limited by hot, wet conditions, while in more central areas of Australia it is limited by hot, dry conditions. Model II is more consistent with the current Australian distribution of E. californica. The contrast in geographical range and climatic conditions encompassed between the two models appears to represent the difference between the realized niche (model I) and fundamental niche (model II) of E. californica. The difference may represent the strength of biotic factors such as host limitation, competition and parasitism in limiting geographical spread in the native range. This paper provides a risk map for E. californica colonization in Australia and globally. E. californica is likely to remain a feature of the Australian pine plantations, and any feasibility studies into establishing coniferous plantations in lower rainfall areas should consider the likely impact of E. californica. [source] Postfledging habitat selection of juvenile middle spotted woodpeckers: a multi-scale approachECOGRAPHY, Issue 4 2009Carlos Ciudad Despite its relevance for the persistence of populations, the ecological mechanisms underlying habitat use decisions of juvenile birds are poorly understood. We examined postfledging habitat selection of radio-tracked juvenile middle spotted woodpeckers Dendrocopos medius at multiple hierarchically-nested spatial scales in NW Spain. At the landscape and home range scales, old oak forest was the most used and selected habitat, young oak forests and pine plantations were avoided, and riverside forests were used as available. At a lower scale, birds selected larger diameter trees for foraging. Home ranges had higher densities of large deciduous trees (mainly oaks Quercus spp., but also poplars Populus spp. and willows Salix spp. >22,cm and >33,cm DBH) selected for foraging by juveniles than non-used areas. These results suggest that foraging conditions may drive, at least partly, habitat use decisions by juvenile birds. We also discuss the potential influence of intraspecific competition, the search for a future breeding territory in the early postfledging period and predation avoidance on habitat use decisions by juvenile birds. Contrary to previous studies on migrant forest birds, postfledging juvenile woodpeckers selected the same habitat as for the breeding adults (i.e. old oak forest), indicating that migrant and resident specialist avian species may require different conservation actions. Conservation strategies of woodpecker populations should consider the protection of old oak forests with high densities of large trees to provide suitable habitat to breeding adults and postfledging juveniles. The habitat improvement for this indicator and umbrella species would also favour other organisms that depend on characteristics of old-growth oak forests. [source] Influences of restock age and habitat patchiness on Tree Pipits Anthus trivialis breeding in Breckland pine plantationsIBIS, Issue 2007NIALL H.K. BURTON The British Tree Pipit Anthus trivialis population has shown a marked decline in recent decades, together with a range contraction that has been most apparent in central and southeast England. In East Anglia, the species is now largely restricted to heathland and, in particular, the conifer plantations established on light soils in these areas. Here I evaluate how Tree Pipits are influenced by the age of pine restock and the patchiness of habitat in Thetford Forest in the Breckland area of Norfolk and Suffolk, eastern England. Both the probability of occurrence and the densities of territory-holding Tree Pipits varied according to the age of coupes of restock , densities peaking in restock 1,6 years old , and were also significantly higher in coupes (a stand comprising one or more forest subcompartments planted in the same year, usually with the same tree crop) in the largest, most central forest block than in smaller, isolated blocks peripheral to this. Within coupes, the distribution and thus densities of Tree Pipits were limited by the availability of songposts. Few songflights finished on the ground or in flight and displaying birds only perched on restock once trees were at least 3 years old (0.8 m high) , thus, territories were only established away from bordering or retained mature trees once restock had reached this age. Pairing success was reduced among males with territories of less than 1 ha, as found in the highest densities in restock, but was unrelated to the proportion of songflights that individuals finished on perches. Thus, although the availability of songposts limited the distribution of the species, it did not appear to affect individual breeding success. The study highlights the importance of pine plantations for the species in lowland England, but also the benefits of large blocks of habitat and targeted forest management, for instance, the retention of mature trees in coupes of restock for Pipits to use as songposts. [source] Influence of land use on plant community composition and diversity in Highland Sourveld grassland in the southern Drakensberg, South AfricaJOURNAL OF APPLIED ECOLOGY, Issue 5 2005T. G. O'CONNOR Summary 1Biodiversity conservation of grasslands in the face of transformation and global climate change will depend mainly on rangelands because of insufficient conservation areas in regions suited to agriculture. Transformed vegetation (pastures, crops and plantations) is not expected to conserve much biodiversity. This study examined the impact of land use on the plant diversity and community composition of the southern Drakensberg grasslands in South Africa, which are threatened with complete transformation to pastures, crops and plantations. 2The main land uses in this high rainfall region are: ranching or dairy production under private tenure using indigenous grassland, pastures (Eragrostis curvula, kikuyu and ryegrass) and maize; plantation forestry; communal tenure (maize and rangelands); and conservation. 3Plant diversity and composition were assessed using Whittaker plots. Transformed cover types were depauperate in species and ranged from kikuyu (1·4 species m,2) and ryegrass (2·9), to pine plantation (3·1), E. curvula pasture (3·1), commercial maize (3·2) and communal maize (7·8). With the exception of pine plantations, these communities supported mostly exotic (50 of 70 species) or ruderal indigenous species and made little contribution to plant species conservation. Abandoned communal cropland reverted to an indigenous grassland almost devoid of exotic species within c. 20 years. 4It was predicted that frequently cultivated sites (maize and ryegrass) would support less diversity than long-lived pastures (kikuyu and E. curvula). This was contradicted by the relatively high species diversity of communal maize fields, which was attributed to a lack of herbicides, and the depauperate communities of kikuyu and of E. curvula pasture, which were attributed, respectively, to a dense growth form and a severe mowing regime. 5Pine plantations harboured fourfold more indigenous species per plot (27) than other transformed types. Species were mostly shade-tolerant grassland relics that had persisted for 12 years since planting, and some forest colonizers. Indigenous species were unlikely to be maintained because of aggressive invasion by the exotic Rubus cuneifolius and severe disturbance associated with tree harvest and replanting. 6The richness of indigenous grasslands was expected to differ in response to grazing pressure but they differed only in composition. Grasslands were dominated by grasses, despite the richness of herbaceous species. The dominance of Themeda triandra was reduced under livestock grazing in favour of more grazing-tolerant species. Exotic species were inconspicuous except for the dicotyledon Richardia brasiliensis, a subdominant under communal grazing. 7Southern Drakensberg grasslands are probably now stocked with livestock six- to 35-fold higher than during pre-settlement times. A grassland protected for c. 50 years supported twofold greater richness (101 species plot,1) than grazed grasslands, suggesting that a 150-year history of increased mammalian grazing had already reduced plant diversity. 8Synthesis and applications. Land acquisition is costly, thus conservation of plant diversity in the southern Drakensberg requires a policy that inhibits transformation of rangelands. This can be achieved by enhancing their economic viability without changing the vegetation composition. Their inherent value must be recognized, such as for water production. The viability of commercial ranches can be improved by increasing their size. Conservation efforts need to be focused on plant taxa that only occur on unprotected rangelands. [source] Endemicity of Afromontane grasshopper assemblages: implications for grassland conservationAFRICAN JOURNAL OF ECOLOGY, Issue 4 2002S. H. Foord Abstract The Drakensberg escarpment in southern Africa is extensively afforested with pine plantations. The Afromontane grasslands in this area have large numbers of endemic plant taxa, but very little is known of their invertebrate fauna. We report on the microgeographical and broad-scale geographical characteristics of grasshoppers and their allies (Orthoptera) at the Groenvaly grassland fragmentation experiment site, South Africa. Pre-fragmentation sampling indicates that control sites and experimental fragments were comparable at the start of the experiment. Of the surveyed species (total 31 species) 25% are endemic to this grassland with another 33% occurring more widely in montane grasslands of south-eastern South Africa. The level of orthopteran endemicity is therefore similar to that of plants, emphasizing the conservation importance of this threatened habitat. There was a significant inverse relation between the degree of stenotopy of a species within the study site and its geographical range in southern Africa, with implications for interpreting the conservation importance of taxonomically and geographically unknown taxa such as the beetles (Coleoptera) in the Afromontane grassland. This information on endemicity of the Afromontane Orthoptera indicates that these grasslands harbour a diverse endemic fauna representing a significant part of southern African biodiversity. Résumé L'escarpement du Drakensberg, en Afrique australe, est largement couvert de plantations de pins. Les prairies afro-montagnardes de cette région comptent un grand nombre de taxons végétaux endémiques, mais on sait très peu de choses de leur faune d'invertébrés. Notre rapport porte sur les caractéristiques micro-géographiques et celles d'une plus grande échelle géographique des sauterelles et de leurs cousins (Orthoptères), sur le site expérimental de fragmentation des prairies de Groenvaly, en Afrique du Sud. L'échantillonnage pré-fragmentation indique que les sites de contrôle et les fragments expérimentaux étaient comparables au début de l'expérience. Des espèces étudiées (31 au total), 25% sont endémiques à cette prairie, tandis que 33 autres pour cent se rencontrent plus largement dans les prairies de montagne, au sud-est de l'Afrique du Sud. Le taux d'endémisme des orthoptères est dès lors semblable à celui des plantes, soulignant davantage l'importance de la conservation de cet habitat menacé. Il y avait une relation inverse significative entre le degré de sténotypie d'une espèce au sein du site étudié et sa distribution géographique en Afrique australe, ce qui a une incidence sur l'interprétation de l'importance de la conservation de taxons géographiquement et taxonomiquement inconnus comme les coléoptères (Coleoptera) de la prairie afro-montagnarde. Ces informations sur l'endémisme des Orthoptères afro-montagnards indiquent que ces prairies abritent une faune endémique variée qui représente une partie significative de la biodiversité de l'Afrique australe. [source] The control of sirex wood wasp using biological control agents in Victoria, AustraliaAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2009N. G. Collett Abstract 1,The sirex woodwasp, Sirex noctilio has been a significant pest of radiata pine plantations in Victoria since 1961. Outbreaks are usually associated with susceptible trees being under some form of stress including the effects of drought and overcrowding. 2,This paper reviews the spread of sirex and the history and efficacy of biological control programmes implemented against sirex in Victoria from 1970 to 2006. 3,Of the numerous biological control agents released, the most effective in managing sirex have been the nematode Beddingia siricidicola and the parasitic wasp Ibalia leucospoides. Several other parasitic wasps such as Schlettererius cinctipes and Megarhyssa nortoni nortoni have also established but provide only minimal control. 4,While rates of I. leucospoides parasitism have improved over time, it is unlikely that this improvement will continue substantially past current levels. 5,In recent years, issues have arisen regarding a decline in the infectivity of B. siricidicola necessitating a re-evaluation of strategies and development of techniques to overcome this problem. 6,Ongoing research using Random Amplification of Polymorphic DNA (RAPD) testing is underway to accurately determine nematode strains and associated infectivity present in plantations in the field in order to develop management strategies to re-introduce more effective strains. [source] Selective manipulation of predators using pheromones: responses to frontalin and ipsdienol pheromone components of bark beetles in the Great Lakes regionAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2005Brian H. Aukema Abstract 1,One proposed approach to improving biological control of bark beetles (Coleoptera: Scolytidae; alt. Curculionidae: Scolytinae) is to manipulate predator movement using semiochemicals. However, selective manipulation is impeded by attraction of both predators and pests to bark beetle pheromones. 2,The primary bark beetle affecting pine plantations in Wisconsin, U.S.A., is the pine engraver, Ips pini (Say). Other herbivores include Ips grandicollis (Eichhoff) and Dryophthorus americanus Bedel (Curculionidae). The predominant predators are the beetles Thanasimus dubius (Cleridae) and Platysoma cylindrica (Histeridae). 3,We conducted field assays using two enantiomeric ratios of ipsdienol, and frontalin plus ,-pinene. Ipsdienol is the principal pheromone component of I. pini, and frontalin is produced by a number of Dendroctonus species. ,-Pinene is a host monoterpene commonly incorporated into commercial frontalin lures. 4,Thanasimus dubius was attracted to frontalin plus ,-pinene, and also to racemic ipsdienol. By contrast, I. pini was attracted to racemic ipsdienol, but showed no attraction to frontalin plus ,-pinene. Platysoma cylindrica was attracted to 97%-(,)-ipsdienol and, to a lesser extent, racemic ipsdienol, but not to frontalin plus ,-pinene. Ips grandicollis was attracted to frontalin plus ,-pinene but not to ipsdienol. Dryophthorus americanus was attracted to both ipsdienol and frontalin plus ,-pinene. 5,This ability to selectively attract the predator T. dubius without attracting the principal bark beetle in the system, I. pini, provides new opportunities for research into augmentative biological control and basic population dynamics. Moreover, the attraction of T. dubius, but not P. cylindrica, to frontalin plus ,-pinene creates opportunities for selective manipulation of just one predator. 6,Patterns of attraction by predators and bark beetles to these compounds appear to reflect various degrees of geographical and host tree overlap with several pheromone-producing species. [source] The history and control of the pine beauty moth, Panolis flammea (D. & S.) (Lepidoptera: Noctuidae), in Scotland from 1976 to 2000AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 3 2001B. J. Hicks Abstract 1,The pine beauty moth, Panolis flammea, has been a serious pest of lodgepole pine plantations in Scotland since 1976. It historically feeds on native Scots pine throughout Europe but population levels of P. flammea on this host have never been high enough to cause tree mortality in the U.K. 2,This paper reviews recent advances in the biology of the pest and documents control programmes from 1976 to 1999. 3,There has been practically uninterrupted population monitoring of P. flammea from 1977 to the present day in Scottish lodgepole pine plantations. Intervention with chemical spraying has often been necessary. 4,The population data suggest that populations of P. flammea may have had a cyclic pattern over the monitoring period, with outbreaks occurring at regular intervals of between 6 and 7 years. 5,The amplitude of population cycles was large during the 1970s and 1980s, but has dampened in recent years. Natural enemies are believed to contribute to this trend. Fungal disease, specifically, appears to have had a greater effect on pest populations in recent years than in the past and is suggested to have contributed significantly to the population dynamics observed since 1990. [source] Anthropogenic changes in the landscape of west Java (Indonesia) during historic times, inferred from a sediment and pollen record from Teluk BantenJOURNAL OF QUATERNARY SCIENCE, Issue 3 2004Sander van der Kaars Abstract Palynological and charcoal analyses of shallow marine core 98-28 from the northern coastal area of West Java provide a regional vegetation history during the last few centuries. Reliable chronostratigraphical control is provided by 210Pb analyses and the occurrence of the 1883 Krakatau ash/tsunami layer as a time marker. The results permit the distinction of four successive stages, reflecting increased disturbance and land clearance, with some evidence for the presence of deciduous lowland forests in the Banten area during the early Holocene. The establishment of coconut and pine plantations and the severe loss of biodiversity in the last few decennia are also echoed in the pollen record. The effect of the Krakatau eruption was insignificant compared with human impact on vegetation in the Banten area. Copyright © 2004 John Wiley & Sons, Ltd. [source] High intercontinental migration rates and population admixture in the sapstain fungus Ophiostoma ipsMOLECULAR ECOLOGY, Issue 1 2007XUDONG ZHOU Abstract Ophiostoma ips is a common fungal associate of various conifer-infesting bark beetles in their native ranges and has been introduced into non-native pine plantations in the Southern Hemisphere. In this study, we used 10 microsatellite markers to investigate the population biology of O. ips in native (Cuba, France, Morocco and USA) and non-native (Australia, Chile and South Africa) areas to characterize host specificity, reproductive behaviour, and the potential origin as well as patterns of spread of the fungus and its insect vectors. The markers resolved a total of 41 alleles and 75 haplotypes. Higher genetic diversity was found in the native populations than in the introduced populations. Based on the origin of the insect vectors, the populations of O. ips in Australia would be expected to reflect a North American origin, and those in Chile and South Africa to reflect a European origin. However, most alleles observed in the native European population were also found in the native North American population; only the allele frequencies among the populations varied. This admixture made it impossible to confirm the origin of the introduced Southern Hemisphere (SH) populations of O. ips. There was also no evidence for specificity of the fungus to particular bark beetle vectors or hosts. Although O. ips is thought to be mainly self-fertilizing, evidence for recombination was found in the four native populations surveyed. The higher genetic diversity in the North American than in the European population suggests that North America could be the possible source region of O. ips. [source] A review of the importance of freshwater inflow to the future conservation of Lake St LuciaAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 7 2009A. K. Whitfield Abstract 1.Lake St Lucia, the oldest formally protected estuary in the world is under threat from historic and present manipulation of freshwater supplies to the system. 2.Constraints to the functioning of the ecosystem began in 1914 with the commencement of draining and canalization of the Mfolozi Swamp to open up the swamp and river floodplain for sugar cane cultivation. Warner's Drain was completed in 1936 and the sediment filtering capability of the swamp on river floodwaters was effectively removed. This resulted in exceptionally high sediment loads from the Mfolozi River entering directly into the St Lucia system and the river was therefore diverted southwards and provided with a separate estuary mouth. This deprived St Lucia of its single largest freshwater supply. 3.During the past 50,60 years, increasing freshwater abstractions from the Mkhuze, Mzinene, Hluhluwe and Nyalazi rivers have contributed to the increasingly severe salinity extremes experienced by Lake St Lucia. In the past decade, desiccation of large areas of False Bay, North and South Lake has occurred, due primarily to natural estuary mouth closure combined with a prolonged drought and unnaturally low freshwater inflows during the closed phase. These events have pushed the system into an extreme state that has not been recorded previously and would not have occurred if Mfolozi River water had been available to the St Lucia system over this drought period. 4.Forestry plantations have further exacerbated the freshwater supply situation, although recent removal of pine plantations on the eastern and western shores of the lake are likely to help restore groundwater flows to the system. 5.This review explores the possibility of relinking the Mfolozi River, once the Mfolozi floodplain swamp has been re-established, to the St Lucia system, thereby bringing urgently needed fresh water to this threatened World Heritage Site. Copyright © 2009 John Wiley & Sons, Ltd. [source] Differences in leaf-litter invertebrate assemblages between radiata pine plantations and neighbouring native eucalypt woodlandAUSTRAL ECOLOGY, Issue 4 2009TESSA C. ROBSON Abstract We investigated the structure, composition and environmental correlates of leaf-litter invertebrate assemblages in Pinus radiata plantations and in neighbouring native eucalypt woodland in the Jenolan Caves Karst Conservation Reserve, south-east Australia. Invertebrate assemblages of plantations were compared with remnant eucalypt woodland located well away from the influence of plantations to determine the direct effects of plantations as a result of habitat-replacement with a non-native plantation species. We also included in our comparisons edge habitat of eucalypt woodland located immediately adjacent to plantations. This unique edge habitat is exposed to the intrusion of large volumes of pine leaf-litter from plantations, which has the potential to affect indirectly invertebrate assemblages of surrounding woodland. We found that species richness of invertebrates was significantly lower in pine plantations compared with remnant eucalypt woodland. There was a complete absence of species from 12 invertebrate orders that were found in surrounding eucalypt woodland. A rich and abundant native plant understorey that provides increased habitat heterogeneity is the most likely explanation for the richer invertebrate assemblage found in remnant eucalypt woodland. The total abundance of all invertebrate taxa in pine plantations in winter was significantly higher than in remnant eucalypt woodland, pine-litter edges and pine-free edges. Plantations were characterized by particularly high abundances of species in two orders, Acari and Collembola. High abundances of acarine and collembolan species in plantations were associated with a decompositional environment represented by comparatively higher moisture contents and higher C : N ratios of both leaf-litter and soil, higher soil conductivity and lower soil pH. We suggest that implementation of The Plantation Biodiversity Benefits Score will be a fruitful way forward to assess the environmental benefits that can be gained from pine plantations in this region of south-eastern Australia. [source] Coarse woody debris in Australian forest ecosystems: A reviewAUSTRAL ECOLOGY, Issue 8 2005GEMMA WOLDENDORP Abstract Coarse woody debris (CWD) is the standing and fallen dead wood in a forest and serves an important role in ecosystem functioning. There have been several studies that include estimates of CWD in Australian forests but little synthesis of these results. This paper presents findings from a literature review of CWD and fine litter quantities. Estimates of forest-floor CWD, snags and litter from the literature are presented for woodland, rainforest, open forest and tall open forest, pine plantation and native hardwood plantation. Mean mass of forest floor CWD in Australian native forests ranged from 19 t ha,1 in woodland to 134 t ha,1 in tall open forest. These values were generally within the range of those observed for similar ecosystems in other parts of the world. Quantities in tall open forests were found to be considerably higher than those observed for hardwood forests in North America, and more similar to the amounts reported for coniferous forests with large sized trees on the west coast of the USA and Canada. Mean proportion of total above-ground biomass as forest floor CWD was approximately 18% in open forests, 16% in tall open forests, 13% in rainforests, and 4% in eucalypt plantations. CWD can be high in exotic pine plantations when there are considerable quantities of residue from previous native forest stands. Mean snag biomass in Australian forests was generally lower than the US mean for snags in conifer forests and higher than hardwood forest. These results are of value for studies of carbon and nutrient stocks and dynamics, habitat values and fire hazards. [source] | ||||||||||||||||||||||