A simulation of the development and restoration of old-growth structural features in northern hardwoods

Thinning treatments in second-growth forest may be a practical means of accelerating the development of certain old-growth structural features in regions where old stands are presently uncommon. We used CANOPY, an individual-tree model calibrated with data from thinned and unthinned stands, to simulate effects of thinning on growth rates and development of old-growth structural features in second-growth northern hardwoods. Three simulated, moderately heavy thinnings over a period of 45 years nearly doubled the predicted mean radial increment of canopy trees, percent of stand basal area in large trees, and area of canopy gaps. Compared to untreated stands, thinned stands had fewer dead trees per ha, but the dead trees were larger in size and the overall volume of snags and logs was little affected. In a 77-year old even-aged stand, moderately heavy thinning was predicted to reduce the time needed to attain the minimum structural features of an old-growth forest from 79 to 36 years. Simulated treatments in an older, uneven-aged stand gave mixed results; the moderately heavy treatment stimulated individual tree growth, but the removal of some medium-sized canopy trees in conjunction with natural mortality delayed the development of old-growth structure. Total volume of dead wood may still be deficient under the thinning regimes investigated in this study, but predicted live-tree structure 45 years after moderately heavy thinning was typical of stands in the advanced transition and steady-state stages of old-growth development. Results suggest that thinning can substantially accelerate the development of old-growth structure in pole and mature northern hardwoods, but response in older, uneven-aged stands is more modest, and treatments in these stands may need to be more conservative to achieve restoration goals.     

More attention to protection and research on old-growth Korean pine (Pinus koraiensis) forests

This paper reviews the researches on old-growth korean pine (Pinus koraoensis) forest in Northeast China. The ecological characteristics of the forest were summarized. According to the research results, the importance of studying and reserving on the old-growth forest was addressed, which were the indispensable research laboratory and classroom for forest managers. The conclusions indicate that the future of Korean pine forest management should be based on the research results of old-growth forests.     

Derivation of a spatially explicit 86-year retrospective carbon budget for a landscape undergoing conversion from old-growth to managed forests on Vancouver Island,BC

To understand the influence of disturbance, age–class structure, and land use on landscape-level carbon (C) budgets during conversion of old-growth forests to managed forests, a spatially explicit, retrospective C budget from 1920 through 2005 was developed for the 2500 ha Oyster River area of Fluxnet-Canada's coastal BC Station. We used the Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3), an inventory-based model, to simulate forest C dynamics. A current (circa 1999) forest inventory for the area was compiled, then overlaid with digitized historic disturbance maps, a 1919 timber cruise map, and a series of historic orthophotographs to generate a GIS coverage of forest cover polygons with unique disturbance histories dating back to 1920. We used the combined data from the historic and current inventory and forest change data to first estimate initial ecosystem C stocks and then to simulate forest dynamics and C budgets for the 86-year period. In 1920, old-growth forest dominated the area and the long-term landscape-level net ecosystem C balance (net biome productivity, NBP) was a small sink (NBP 0.2 Mg C ha⁻¹ year⁻¹). From 1930 to 1945 fires, logging, and slash burning resulted in large losses of biomass C, emissions of C to the atmosphere, and transfers of C from biomass to detritus and wood products (NBP ranged from −3 to −56 Mg C ha⁻¹ year⁻¹). Live biomass C stocks slowly recovered following this period of high disturbance but the area remained a C source until the mid 1950s. From 1960 to 1987 disturbance was minimal and the area was a C sink (NBP ranged from 3 to 6 Mg C ha⁻¹ year⁻¹). As harvest of second-growth forest began in late 1980s, disturbances again dominated the area's C budget, partially offset by ongoing C uptake by biomass in recovering young forests such that the C balance varied from positive to negative depending upon the area disturbed that year (NBP from 6 to −15 Mg C ha⁻¹ year⁻¹). Despite their high productivity, the area's forests are not likely to attain C densities of the landscape prior to industrial logging because the stands will not reach pre-logging ages. Additional work is underway to examine the relative role historic climate variability has had on the landscape-level C budget.     

Age structure and spatial pattern of old-growth korean pine forest in Xiaoxing’anling Mountain

Spatial pattern of trees, basal stem increment and height were examined in a 5.0 ha mixed deciduous/Pinus koraiensis forest from October in 1984 to May in 1987. Conclusions are as following: 1. Analysis of the age-structure of the korcan pine forest shows that it is different from general steady-state forest type. The lack of saplings and individuals in small-diameter class clearly indicates that regeneration is not continuous. Continuous regeneration depends on thinning of the canopy to form a gap. Similar-aged korcan pine sccdings grow in these gaps. 2. The horizontal structure of the korcan pine is a mosaic of more or less even-aged groups of trees. The mosaic is a result of korcan pine by regeneration strategy. The aggregations of korcan pine of different ages overlaps to form a continuous population generation. As a results, the population is maintained in steady state.     

Composition, structure and dynamics of Dysart Woods, an old-growth mixed mesophytic forest of southeastern Ohio

Dysart Woods is a 23 ha old-growth remnant of mixed mesophytic vegetation located in southeastern Ohio, USA. A designation of mixed mesophytic for this forest has historically been difficult, in part due to the abundance of white oak (Quercus alba); however, the dominance of a variety of other hardwoods prevents a simple oak forest designation. Using two 0.35 ha plots on opposing north- and south-facing slopes, we describe the structure and composition of the overstory, understory, and soils, 30 years after their first examination. In 1970, the woods was dominated by beech (Fagus grandifolia), white oak, and sugar maple (Acer saccharum) — historically, the three most abundant species in this region. At that time, white oak was only present in the largest size classes, was not regenerating, and was predicted to decline in importance through succession. These patterns continue today suggesting that inferences made via overstory–understory relations in regards to forest succession are relatively robust over this time period. Beech and maple have increased in importance; white oak has decreased in importance due to mortality in the larger size classes and decreasing density due to regeneration failure. Coarse woody debris distributions correlated strongly with living stem species’ composition and structure implying an equilibrium balance. CWD volume and frequency were dominated by Quercus spp. A detailed analysis of forest health showed that all oak species were in severe decline. The oaks are in a disease decline spiral affiliated with a variety of pre-disposing and inciting factors which include their advanced age (>300 years), their large size (> 100 cm DBH), topography, chronic air pollution, drought, and Armillaria root rot fungus. Ca:Al molar ratios in the soil are also extremely low (<1.0) and may be having an additional detrimental effect. All other canopy species appear to be healthy. One of the unusual features of this woods is its relatively diverse and high coverage (up to 90%) understory layer. The herbaceous community was sampled throughout the growing season and found to be markedly dissimilar among sample times and habitat productivity (aspect, soil quality, and light). The role of these factors has not been as well studied for herb communities as it has for tree communities. There appears to be a relatively strong linkage between the overstory regeneration and understory coverage. While a variety of woody seedlings were discovered, most were of shade tolerant species. Only a few small seedlings of white oak were discovered, with none advancing past 30 cm in height, indicating strong competition in the understory. Furthermore, this small remnant forest patch is surrounded by an agricultural and second-growth forest matrix with many non-indigenous plants — none of which have been able to enter the woods, suggesting strong equilibrium stability of these old-growth patches. The hardwood forests of the hills region has been heavily impacted by various human cultures for thousands of years. Dendrochronological analysis of a full basal slab cut from a wind-thrown white oak revealed a fairly active period of fire following European settlement. A lack of fire during the early 1600s to mid 1700s suggests that pre-Anglo fire frequency may have been negligible. There is clearly a continued role for the preservation and study of these old-growth remnants. They remain integrally important as we attempt to understand and better manage our remaining anthropogenically disturbed landscape.     

Predicting canopy macrolichen diversity and abundance within old-growth inland temperate rainforests

Windward slopes of the inland mountain ranges in British Columbia support a unique inland temperate rainforest (ITR) ecosystem. Increasing fragmentation and the loss of old ITR stands have highlighted the need for determining conservation biology priorities among remaining old forest stands. We have addressed this issue by surveying foliose macrolichens within 53 old ITR stands in British Columbia's 135,000 ha very wet-cool interior-cedar hemlock (ICHvk2) biogeoclimatic subzone in the upper Fraser River watershed. Study plots were stratified by leading tree species and by “wet” versus “dry” relative soil moisture conditions. Other plot variables included: temperature, precipitation, incident solar loading, and canopy openness. Ordination plots showed a distinct assemblage of foliose cyanolichens, including Lobaria pulmonaria, Lobaria retigera, Sticta fuliginosa, Nephroma isidiosum, Nephroma occultum, and Pseudocyphellaria anomala, whose abundance was correlated with increasing relative soil moisture, temperature, canopy openness, precipitation, and basal area of spruce. Logistic regression models similarly identified relative soil moisture and temperature in all parsimonious models. Leading tree species, in combination with “wet” relative soil moisture and/or temperature, were important factors explaining the presence or absence of five (Cavernularia hultenii, L. retigera, N. occultum, Platismatia norvegica, and Sticta oroborealis) of the eight modeled old-growth associate lichen species. This combination of conditions favouring the development of canopy lichen communities in old forests was best expressed in low elevation water receiving sites. We hypothesize that groundwater availability in these sites promotes species richness and abundance of canopy lichens by creating more favourable conditions for growth, and by reducing fire return intervals which allows for the accumulation of rare species over time. Historically, forests in these wet “toe-slope” positions were disproportionately targeted for logging. Their conservation should now be a high priority, given their disproportionate significance to maintaining canopy lichen diversity in the present-day landscapes.     

Structural and environmental characterization of old-growth temperate rainforests of northern Chiloé Island,Chile: Regional and global relevance

Old-growth forests are ecologically relevant reservoirs of biodiversity and provide valuable and unique ecosystem functions in the landscape. However, what constitutes an old-growth stand is confusing because the definition depends largely on the forest type under study. Despite the ecological importance of old-growth temperate rainforests in southern Chile in comparison to other global forests, no attempts have been made to characterize them as a way to assess their structural variability. Here, we characterized old-growth stands of Valdivian and North Patagonian rain forest types located in Chiloé Island (Chile, 42°30′S) using inventory data from 23 permanent plots (0.1 ha each) located in rural landscapes and protected areas of northern Chiloé Island. For each stand, its age (average age of the oldest trees present in each stand) and disturbance regimes (evidence of recent human impact, e.g. cuttings or fires, and tree growth rates) were used as defining old-growth criteria. We characterized the structure (tree species richness, size-density distributions, vertical stratification and presence of snags) and floristic composition of each stand. Environmental variables (i.e. temperature, distance to coastline and elevation) were related to stand structure using multivariate constrained correspondence analysis. Old-growth forests were commonly characterized by (a) tree basal areas >80 m²/ha; (b) density of shade-tolerant tree species in the emergent and dominant canopy layer >36%; (c) higher tree species richness (>7 tree species) than successional stands; (d) presence of large canopy emergents (>80 cm dbh, >25 m tall); (e) high vertical heterogeneity; and (f) minimum stand ages older than 200 years. Old-growth forests showed a distinctive structural variability and floristic diversity influenced both by stand age and disturbance history of the stands. Structural variability was also related to environmental differences among sites (e.g. air temperature, distance to coastline, soil types). Old-growth forest features described here can offer a baseline for managers interested in maintaining and restoring old-growth forest structure in southern temperate rain forests.     

抗旱造林集成技术

着重从集流技术,节水保墒、增加植物对水分有效利用三个方面论述了抗旱造林的重要方式。     

Carbon storage in old-growth and second growth fire-dependent western larch (Larix occidentalis Nutt.) forests of the Inland Northwest,USA

There is limited understanding of the carbon (C) storage capacity and overall ecological structure of old-growth forests of western Montana, leaving little ability to evaluate the role of old-growth forests in regional C cycles and ecosystem level C storage capacity. To investigate the difference in C storage between equivalent stands of contrasting age classes and management histories, we surveyed paired old-growth and second growth western larch (Larix occidentalis Nutt)–Douglas-fir (Pseudostuga menziesii var. glauca) stands in northwestern Montana. The specific objectives of this study were to: (1) estimate ecosystem C of old-growth and second growth western larch stands; (2) compare C storage of paired old-growth–second growth stands; and (3) assess differences in ecosystem function and structure between the two age classes, specifically measuring C associated with mineral soil, forest floor, coarse woody debris (CWD), understory, and overstory, as well as overall structure of vegetation. Stands were surveyed using a modified USFS FIA protocol, focusing on ecological components related to soil, forest floor, and overstory C. All downed wood, forest floor, and soil samples were then analyzed for total C and total nitrogen (N). Total ecosystem C in the old-growth forests was significantly greater than that in second growth forests, storing over 3 times the C. Average total mineral soil C was not significantly different in second growth stands compared to old-growth stands; however, total C of the forest floor was significantly greater in old-growth (23.8 Mg ha⁻¹) compared to second growth stands (4.9 Mg ha⁻¹). Overstory and coarse root biomass held the greatest differences in ecosystem C between the two stand types (old-growth, second growth), with nearly 7 times more C in old-growth trees than trees found on second growth stands (144.2 Mg ha⁻¹ vs. 23.8 Mg ha⁻¹). Total CWD on old-growth stands accounted for almost 19 times more C than CWD found in second growth stands. Soil bulk density was also significantly higher on second growth stands some 30+ years after harvest, demonstrating long-term impacts of harvest on soil. Results suggest ecological components specific to old-growth western larch forests, such as coarse root biomass, large amounts of CWD, and a thick forest floor layer are important contributors to long-term C storage within these ecosystems. This, combined with functional implications of contrasts in C distribution and dynamics, suggest that old-growth western larch/Douglas-fir forests are both functionally and structurally distinctive from their second growth counterparts.     

云南省膏桐营造林技术

膏桐为重要的生物质能源树种,云南省适宜栽培地区为金沙江、红河、南盘江、怒江流域海拔1 600 m以下南亚热带、半湿润地区、干暖地区、半干旱地区.介绍了膏桐的生物学特性及造林技术:造林地选择、种苗准备、林地清理、造林密度、栽植方式方法、抚育管理以及整形修枝、施肥管理、灌溉排水、病虫害防治、种子采收等经营管理措施.     

云南省膏桐营造林技术

膏桐为重要的生物质能源树种,云南省适宜栽培地区为金沙江、红河、南盘江、怒江流域海拔1600m以下南亚热带、半湿润地区、干暖地区、半干旱地区．介绍了膏桐的生物学特性及造林技术：造林地选择、种苗准备、林地清理、造林密度、栽植方式方法、抚育管理以及整形修枝、施肥管理、灌溉排水、病虫害防治、种子采收等经营管理措施．     

啤酒花的栽培技术

啤酒花在酿酒、医疗、保健等方面具有重要价值。林区、农区和牧区有计划地栽培及开发使用，可获较高的经济效益。     

Determining structural variation in a managed mixed stand in an old-growth forest,northern Iran

Numerous approaches have been developed to quantify forest structure modules.A variety has measured each as part of stand attributes.This study was carried out in managed mixed stands in northern Iran.The objective was to quantify stand structure and its variation before and after tree marking through the Gini index and structural triangle method.A full sampling inventory was taken in 2004 and 2014 at the beginning and end of a period,before and after tree marking operations in five stands.The results indicate that the Gini index was 39.5,62.2,43.0,82.0 and 74.0%forⅠ,Ⅱ,Ⅲ,ⅣandⅤstands respectively.Furthermore,approximate structural diameters were determined as a large category forⅠ,Ⅱ,ⅢandⅤstands while standⅡhad an intermediate-large class pre-tree marking to an intermediate-small class post-tree marking.The paired t-test results were not significant for tree numbers and growing stock changes for all species,and for beech,hornbeam,and velvet maple before and after tree harvesting in the whole stand.Therefore,the Gini index and the structural triangle method can be used for natural stand modeling,structural diversity designation,and for management practices in nature-oriented forestry strategies.     

五味子栽培技术

五味子是一种药用价值很高的藤本植物,是我省的乡土种,发展五味子栽培是山区群众致富的的一条新途径。本文讲述了五味子的人工栽培技术,药用成分、药理作用和发展五味子栽培、加工的对策。     

小叶白腊种子园营建技术

小叶白腊（Fraxinus sogdiana Bunge）属木樨科白腊树属,是我国新疆特有的树种,其植株高大,树形优美,材质好,是营建用材林及农田防护林的优良树种,也是新疆城市绿化的首选树种之一。目前,小叶白腊已成为新疆濒危树种。为了更好地研究、保护和利用小叶白腊,提供切实可行的保护措施,我们于1984年开始在全疆范围内收集小叶白腊优树,并进行采种,当年秋季育苗,苗期试验3a,1987年建立小叶白腊种子园,旨在研究小叶白腊的生理特性及遗传品质,培育优良的小叶白腊种子,实现小叶腊种子生产良种化、专业化、基地化。     

浙江省营林技术决策咨询系统

“浙江省营林技术决策咨询系统”，集营林技术决策与咨询为一体，涵盖针阔用材林、经济林、竹林等140个浙江省常见的造林树种。该系统应用计算机辅助设计技术、实现在特定立地条件下选择适宜生长的树种，并进行效益优化分析，大大推进营林生产决策科学化、定量化进程。该软件已获计算机软件著作权登记保护。     

侧柏造林研究初报

侧柏在山西省的天然分布仅限于内长城以南,为实现雁门关外造林树种的多样性,从1996年起在怀仁县进行了侧柏造林试验.结果表明,侧柏在本区的栽培区应限制在桑干河流域的薛家庄、金沙滩、落阵营、九梁洼林场,不宜在山顶风口和迎风的山坡栽植.种子应尽量在本地或内蒙地区采摘,宜采用3年生留床苗或2+1的移植苗,与阔叶树种混交效果最好.     

中欧地区的森林培育及其启示

文中简述了中欧的林业发展史，特别对德国森林培育的现状和存在的问题进行了比较详细的分析。根据德国森林培育的历史和经验，提出了对中国林业建设的几点启示。     

桉树大径材培育技术研究概述

培育大径材用于实木加工是桉树人工林发展的趋势,但桉树人工林大径级原木的培育尚缺乏经验。本文综述了国内外在桉树大径材树种选择、初植密度控制、间伐、修枝和施肥管理方面的现状及其对大径材生长和材性的影响,以期为桉树资源高效利用及大径材人工林的可持续发展提供借鉴和依据。