Effects of postfire climate and seed availability on postfire conifer regeneration

2020 ◽  
Author(s):  
Joseph A.E. Stewart ◽  
Phillip J. van Mantgem ◽  
Derek J.N. Young ◽  
Kristen L. Shive ◽  
Haiganoush K. Preisler ◽  
...  
Keyword(s):  
Seed Availability ◽  
Conifer Regeneration

Controls on conifer regeneration in managed riparian forests: effects of seed source, substrate, and vegetation

2001 ◽  
Vol 31 (3) ◽  
pp. 471-482 ◽  
Author(s):  
Eric W Beach ◽  
Charles B Halpern
Keyword(s):  
Pacific Northwest ◽  
Woody Debris ◽  
Full Range ◽  
Plant Cover ◽  
Riparian Forests ◽  
Competitive Interactions ◽  
Vegetation Control ◽  
Seed Availability ◽  
Seed Sources ◽  
Conifer Regeneration

Red alder (Alnus rubra Bong.) commonly dominates the overstory in managed riparian forests of the Pacific Northwest. Although it is assumed that competition with a dense shrub layer inhibits succession from hardwoods to shade-tolerant conifers within these forests, this assumption has not been explicitly tested. We hypothesized that seed availability rather than competitive interactions largely shape patterns of conifer regeneration in managed riparian forests. At nine locations in western Washington, we established paired transects in riparian sites adjacent to abundant versus few or no sources of seed to examine the importance for conifer regeneration of dispersal limitation, rooting substrate, and vegetation cover. Frequency and density of regeneration were significantly greater in transects within 100 m of remnant forest patches than in paired sites at greater distances (mean frequencies of 59 vs. 18% and densities of 0.23 vs. 0.16 trees/m2, respectively). Where seed sources were present, regeneration was positively associated with coarse woody debris and negatively associated with fine litter. Regeneration was most abundant in plots with <10% herb or shrub cover; however, for most species, recruitment occurred across the full range of understory plant cover. We detected no relationship between regeneration density and overstory conifer or hardwood cover. Our results suggest that, in managed forests, conifer regeneration is largely limited by seed availability and only secondarily by competitive interactions or substrate conditions. In managed landscapes, conventional strategies of vegetation control are not likely to be as effective in increasing conifer regeneration in riparian forests as managing for seed sources through green-tree retention.

scholarly journals Post-Wildfire Logging Hinders Regeneration and Increases Fire Risk

Science ◽  
2006 ◽  
Vol 311 (5759) ◽  
pp. 352-352 ◽  
Author(s):  
D. C. Donato ◽  
J. B. Fontaine ◽  
J. L. Campbell ◽  
W. D. Robinson ◽  
J. B. Kauffman ◽  
...  
Keyword(s):  
Fire Risk ◽  
Fuel Reduction ◽  
Short Term ◽  
High Severity ◽  
Fuel Loads ◽  
Conifer Regeneration ◽  
Biscuit Fire ◽  
Additional Reduction

We present data from a study of early conifer regeneration and fuel loads after the 2002 Biscuit Fire, Oregon, USA, with and without postfire logging. Natural conifer regeneration was abundant after the high-severity fire. Postfire logging reduced median regeneration density by 71%, significantly increased downed woody fuels, and thus increased short-term fire risk. Additional reduction of fuels is necessary for effective mitigation of fire risk. Postfire logging can be counterproductive to the goals of forest regenration and fuel reduction.

scholarly journals Pengembangan Kedelai di Sawah Irigasi Pantura Jawa Barat

2016 ◽  
Vol 16 (1) ◽  
pp. 9
Author(s):  
Wayan Sudana
Keyword(s):  
Influencing Factors ◽  
Coastal Region ◽  
The Other ◽  
Farm Income ◽  
Good Seed ◽  
Rural Employment ◽  
Seed Availability ◽  
The Government ◽  
Area Expansion ◽  
Further Development

<p><strong>English</strong><br />Soybean consumption has grown rapidly, but its production increased at a much lower rate, and as a result its demand can only be met by import. On the other hand, the irrigated land most suitable for soybean development is still in a large potential. To utilize the resource, the government made a special effort through intensification and area expansion program as well. The irrigated lowland at West Java northern coastal region is one of strategic opportunities to boost soybean production based on location, accessibility and land suitability. Soybean is usually produced in the second dry season (July-September), and it is expected to increase farm income, to create rural employment opportunity especially for landless farmer. Some influencing factors for further development are among others good seed availability, irrigation and competition of labor used.</p><p> </p><p><strong>Indonesian</strong><br />Pertumbuhan konsumsi kedelai dari tahun ke tahun terus mengalami peningkatan, sehingga mengakibatkan ketidakseimbangan pertumbuhan konsumsi dan produksi kedelai dalam negeri. Untuk menutupi kekurangan konsumsi dalam negeri terpaksa dilakukan impor. Di lain pihak potensi lahan yang cocok untuk pengembangan kedelai ini masih cukup besar. Untuk memanfaatkan potensi sumberdaya lahan ini pemerintah berusaha melalui berbagai upaya khusus baik melalui intensifikasi maupun ekstensifikasi. Sawah irigasi teknis di Pantura Jawa Barat merupakan salahsatu peluang pengembangan kedelai yang sangat strategis bila dilihat dari letak, aksessibilitas dan kesesuaian bio-fisik lahan. Pengembangan kedelai di lahan ini pada MK II (Juli - September) disamping dapat meningkatkan penerimaan usahatani juga membuka peluang kesempatan kerja bagi buruhtani di pedesaan. Untuk pengembangan selanjutnya faktor yang perlu diperhatikan untuk menunjang keberhasilan program ini antara lain kelembagaan penyediaan benih bermutu, pengaturan air serta persaingan penggunaan tenaga kerja.</p>

Effects of disperser abundance, seed type, and interspecific seed availability on dispersal distance

2012 ◽  
Vol 58 (3) ◽  
pp. 267-278 ◽  
Author(s):  
Changqu Liu ◽  
Guoliang Liu ◽  
Zhen Shen ◽  
Xianfeng Yi
Keyword(s):  
Dispersal Distance ◽  
Seed Type ◽  
Seed Availability

Roadsides are key habitats for birds in the Argentine Pampas: conservation and management implications

2021 ◽  
pp. 1-6
Author(s):  
Daniela María Depalma ◽  
Mariela Verónica Lacoretz ◽  
Cecilia Zilli ◽  
Emilio Martín Charnelli ◽  
Myriam Emilia Mermoz
Keyword(s):  
Management Strategies ◽  
Tall Grass ◽  
Vegetation Diversity ◽  
Seed Availability ◽  
Bird Richness ◽  
Public Areas ◽  
Declining Species ◽  
Native Birds ◽  
Argentine Pampas ◽  
Conservation And Management

Summary Unexploited public areas such as roadsides could provide habitat to help preserve biodiversity in South America, as in other regions. Our objective was to determine the importance of the roadsides of the Argentine Pampas for native birds and to suggest management strategies. We surveyed birds inhabiting roadsides in all seasons and determined whether roadsides were used as habitat. We recorded a total of 95 species on roadsides, which represents 55% of those species described from the area. Species included specialists of grassland, wetland and woodland, 4 vulnerable species and 19 declining species. Bird richness decreased in winter, as well as grassland specialists’ abundances. Most individuals used roadsides for foraging and performing reproduction-related behaviours, mainly on native trees; these and tall grass were the main substrates. We conclude that many species of birds use the habitat provided by roadsides, and we recommend management strategies such as favouring seed availability in winter, restoring trees and tall grass and increasing vegetation diversity to maximize roadside conservation value.

Effects of stand parameters on conifer regeneration success in pine shelterwood stands in Estonia

2020 ◽  
Vol 139 (1) ◽  
pp. 29-40
Author(s):  
Raul Rosenvald ◽  
Katrin Rosenvald ◽  
Tanel Kaart ◽  
Erko Soolmann
Keyword(s):  
Conifer Regeneration ◽  
Stand Parameters

scholarly journals Abundance and Impacts of Competing Species on Conifer Regeneration Following Careful Logging in the Eastern Canadian Boreal Forest

Forests ◽  
2019 ◽  
Vol 10 (2) ◽  
pp. 177 ◽  
Author(s):  
Louis-Philippe Ménard ◽  
Jean-Claude Ruel ◽  
Nelson Thiffault
Keyword(s):  
Boreal Forest ◽  
Basal Area ◽  
Low Fertility ◽  
Percent Cover ◽  
Large Area ◽  
Competing Species ◽  
Competing Vegetation ◽  
Conifer Regeneration ◽  
Ericaceous Shrubs ◽  
Canadian Boreal Forest

Managing competing vegetation is crucial in stand establishment strategies; forecasting the abundance, composition, and impact of competing vegetation after harvesting is needed to optimize silviculture scenarios and maintain long-term site productivity. Our main objective was to identify factors influencing the short-term abundance and composition of competing vegetation over a large area of the Canadian boreal forest. Our second objective was to better understand the mid-term evolution of the regeneration/competing vegetation complex in cases of marginal regeneration conditions. We used operational regeneration surveys of 4471 transects sampled ≈5 years after harvesting that contained data on regeneration, competing vegetation, elevation, ecological classification, soil attributes, and pre-harvest forest stands. We performed a redundancy analysis to identify the relationships between competing vegetation, harvesting and biophysical variables. We then estimated the probability of observing a given competing species cover based on these variables. In 2015, we re-sampled a portion of the sites, where conifer regeneration was marginal early after harvesting, to assess the temporal impact of different competing levels and species groups on the free-to-grow stocking, vigour and basal area of softwood regeneration. Results from the first inventory showed that, after careful logging around advance growth, ericaceous shrubs and hardwoods were not associated with the same sets of site attributes. Ericaceous shrubs were mainly found on low fertility sites associated with black spruce (Picea mariana (Mill.) BSP) or jack pine (Pinus banksiana Lamb.). The distinction between suitable environments for commercial shade-intolerant hardwoods and non-commercial hardwoods was less clear, as they responded similarly to many variables. Analysis of data from the second inventory showed a significant improvement in conifer free-to-grow stocking when commercial shade-intolerant hardwood competing levels were low (stocking 0%–40%) and when ericaceous shrubs competing levels were moderate (percent cover 26%–75%). In these conditions of marginal regeneration, the different types and intensities of competition did not affect the vigour or basal area of softwood regeneration, 9–14 years after harvesting.

The repeatability of stem exclusion during even-aged development of bigtooth aspen dominated forests

1993 ◽  
Vol 23 (6) ◽  
pp. 1156-1168 ◽  
Author(s):  
Brian J. Palik ◽  
Kurt S. Pregitzer
Keyword(s):  
Resource Availability ◽  
Radial Growth ◽  
Developmental Pattern ◽  
Forest Understory ◽  
White Pine ◽  
Development Patterns ◽  
Forest Development ◽  
Seed Availability ◽  
Initial Cohort ◽  
Landscape Level

Forest development following major disturbance is thought to follow a fairly repeatable temporal pattern. An initial cohort of trees establishes relatively rapidly (stand initiation), new establishment is precluded for an extended period (stem exclusion), and finally, new individuals again begin to establish, creating new age-classes in the forest understory (understory reinitiation), eventually leading to an uneven-aged condition. The current study was designed to assess the generality of this developmental pattern at the landscape level and gain insight into the possible mechanisms controlling stem exclusion and understory reinitiation in even-aged forests. Research was conducted within two bigtooth aspen (Populusgrandidentata Michx.) dominated landscapes in northern Lower Michigan having similar physical site characteristics, overstory compositions, and disturbance histories. The objectives for the study included (i) assessing the repeatability of development patterns within and between the two landscapes and (ii) exploring relationships between the timing of understory reinitiation and overstory growth characteristics and seed availability. Stem analysis was used to reconstruct establishment and growth histories of surviving stems in mature forest on replicate plots within each landscape. The age distributions of surviving individuals of all tree species in both forests reflected a developmental pattern characterized by rapid initial cohort establishment lasting 5–15 years, stem exclusion lasting 25–35 years, and understory reinitiation. The duration and timing of the developmental stages on the replicate plots were similar both within and between the two landscapes. There were, however, a small number of plots in landscape 2 that had substantially reduced stem exclusion lengths, relative to the remaining plots in both forests. Variation in the timing of understory reinitiation in landscape 2 was related to characteristics of remnant eastern white pine (Pinusstrobus L.) seed trees. The stem exclusion period was shorter, or almost nonexistent, on plots close to several large seed trees because of early, low-frequency establishment of white pine in the understory. Substantial increases in the frequency of understory establishment on all plots in landscape 2, as well as all new understory establishment on plots in landscape 1, were often associated with radial growth increases in overstory stems. The radial growth increases presumably reflected an increase in resource availability, possibly occurring in response to a concentrated wave of natural thinning within the bigtooth aspen dominated overstory. These results suggests that the timing of understory reinitiation may have been influenced by variation in seed availability interacting with changes in resource availability in the forest understory. A limited amount of new establishment occurred relatively early in forest development on plots that experienced abundant early seed rain, yet the bulk of new establishment occurred only after an increase in resource availability in the understory. The general patterns of forest development described in this study were similar both within and between landscapes. Similar descriptive studies are needed to address the repeatability of development patterns at the landscape level within other forest types. Additionally, experimental studies are needed to unequivocally identify the mechanisms controlling stem exclusion and understory reinitiation in even-aged forests.

Sign in / Sign up

Export Citation Format

Share Document