Trophic and non-trophic pathways mediate apparent competition through post-dispersal seed predation in a Patagonian mixed forest

Oikos ◽  
2006 ◽  
Vol 113 (3) ◽  
pp. 469-480 ◽  
Author(s):  
Fernando D. Caccia ◽  
Enrique J. Chaneton ◽  
Thomas Kitzberger
Keyword(s):  
Seed Predation ◽  
Mixed Forest ◽  
Apparent Competition ◽  
Trophic Pathways

scholarly journals Native seed dispersal by rodents is negatively influenced by an invasive shrub

2021 ◽  
pp. 53-67
Author(s):  
A. F. Malo ◽  
A. Taylor ◽  
M. Díaz
Keyword(s):  
Seed Dispersal ◽  
Seed Predation ◽  
Seedling Survival ◽  
Apparent Competition ◽  
Acer Pseudoplatanus ◽  
Pedunculate Oak ◽  
Seed Fate ◽  
Factors Affecting ◽  
Native Seed ◽  
Open Woodland

Refuge–mediated apparent competition is the mechanism by which invasive plants increase pressure on native plants by providing refuge for generalist consumers. In the UK, the invasive Rhododendron ponticum does not provide food for generalist seed consumers like rodents, but evergreen canopy provides refuge from rodent predators, and predation and pilferage risk are key factors affecting rodent foraging and caching behaviour. Here we used a seed removal/ seed fate experiment to understand how invasion by an evergreen shrub can alter seed dispersal, seed fate and early recruitment of native trees. We used seeds of four species, small and wind–dispersed (sycamore maple Acer pseudoplatanus and European ash Fraxinus excelsior) and large and animal–dispersed (pedunculate oak Quercus robur and common hazel Corylus avellana), and monitored seed predation and caching in open woodland, edge habitats, and under Rhododendron. In the open woodland, wind–dispersed seeds had a higher probability of being eaten in situ than cached seeds, while the opposite occurred with animal–dispersed seeds. The latter were removed from the open woodland and edge habitats and cached under Rhododendron. This pattern was expected if predation risk was the main factor influencing the decision to eat or to cach a seed. Enhanced dispersal towards Rhododendron cover did not increase the prospects for seed survival, as density of hazel and oak saplings under its cover was close to zero as compared to open woodland, possibly due to increased cache pilferage or low seedling survival under dense shade, or both. Enhanced seed predation of ash and sycamore seeds close to Rhododendron cover also decreased recruitment of these trees. Rhododendron patches biased rodent foraging behaviour towards the negative (net predation) side of the conditional rodent / tree interaction. This effect will potentially impact native woodland regeneration and further facilitate Rhododendron spread due to refuge–mediated apparent competition.

Seed predation patterns favor the regeneration of dominant species in forest gaps compared with the understory in an oak-pine mixed forest

2014 ◽  
Vol 59 (4) ◽  
pp. 495-502 ◽  
Author(s):  
Fei Yu ◽  
Xiaoxiao Shi ◽  
Dexiang Wang ◽  
Tao Wang ◽  
Xianfeng Yi ◽  
...  
Keyword(s):  
Seed Predation ◽  
Dominant Species ◽  
Mixed Forest ◽  
Forest Gaps

Mit Initialfemeln zum Plenterwald (Essay) | The creation of selection forest using initial femel cut (essay)

2009 ◽  
Vol 160 (6) ◽  
pp. 137-143
Author(s):  
Rudi Kynast
Keyword(s):  
Mixed Forest ◽  
Point Of View ◽  
Age Group ◽  
Black Forest ◽  
Crown Height ◽  
Short Intervals ◽  
Total Growth ◽  
Cost Calculations ◽  
Selection Forest ◽  
Individual Trees

Although selection forests have clear advantages over age-group forests in view of their total growth performance, their net product and their stability, not to mention the sustainability of their beneficial effect, the proportion of this type of forest is insignificantly small in Germany and also in mixed forest in the mountains. It is therefore all the more surprising that scarcely any discernable efforts have been made to increase the proportion of selection forests. For a conversion, an alternative model for the treatment of the stands is adopted, whereby it is no longer the encouragement of the growth to maturity of individual trees in the stand which is aimed for, but rather the transformation of the whole stand to a selection forest using available stand elements and elements created by an early initiation of regeneration. Based on his experience in the forestry district of Kirchzarten in the Black Forest, Germany, the author describes the procedure for a successful conversion. This is to be started as soon as possible, that is to say when the crown height of the trees is about 18 metres and with corresponding usable dimensions, using small group shelter-wood cuts, a so-called initial femel cut. To get the conversion started it is advisable to remove whole groups of predominantly badly situated and overgrown trees. The stand will be additionally structured later through further interventions at short intervals. In the process, here and there really well situated trees will actually be left to stand solitar y, in other places w hol e self-cont aine d groups will b e created and else where valuabl e mixed s tand elements will be selected for permanent preservation, this in order to create a situation in which there are about 35 overstorey trees per hectare. On the basis of his own cost calculations, the author comes to the conclusion that the conversion is, from a financial point of view, superior compared with the age-group forest in that it brings higher proceeds more quickly and more often.

Community dynamics of a montane Fagus engleriana–Cyclobalanopsis multiervis mixed forest in Shennongjia, Hubei, China

2013 ◽  
Vol 20 (6) ◽  
pp. 643-653
Author(s):  
Ge Jielin ◽  
Xiong Gaoming ◽  
Deng Longqiang ◽  
Zhao Changming ◽  
Shen Guozhen ◽  
...  
Keyword(s):  
Community Dynamics ◽  
Mixed Forest ◽  
Fagus Engleriana

Silvicultural characteristics of a Scots pine stand on drift sands

1992 ◽  
Vol 57 ◽  
Author(s):  
D. Maddelein ◽  
N. Lust
Keyword(s):  
Scots Pine ◽  
Mixed Forest ◽  
Rotation Period ◽  
Average Height ◽  
Indigenous Species ◽  
Pedunculate Oak ◽  
Black Cherry ◽  
Humus Layer ◽  
Pine Seedlings ◽  
Pine Regeneration

The  study of a seventy years old stand of Scots pine on drift sands proves that  Scots pine growth on these sites was and is still relatively good: average  diameter 27.6 cm, average height 19.4 m, standing volume 213 m3 and an annual increment  of 4.9 m3.ha-1.yr-1. All Scots pines  belong to the upper storey. Yet considerable differences in crown development  and vitality are observed. The current growth rate and the spontaneous  settlement of pine seedlings under canopy show the ideal conditions for the  creation of a high forest with reserves. Anyway a rotation period of more  than 70 years is recommendable.     On several places a consolidated regeneration of Scots pine seedlings under  canopy occur. Groups with a stem number of 700 to 3,500 seedlings per are, ranging  in age from 3 to 11 years and in height from 10 to 170 cm, are present. This  Scots pine regeneration has developed in a normal mor humus layer and in a  dense Deschampsia mat.      Broadleaved regeneration is not so abundant, and consists for 75 % of black  cherry. Absence of seed trees, browsing damage and the exclusive character of  black cherry are the limiting factors for the installation and survival of  valuable indigenous species, such as pedunculate oak.     Provided that black cherry is removed and that the regeneration is  protected against wild damage, it is possible to create a mixed forest  dominated by Scots pine but with a considerable admixture of indigenous  broadleaved trees. However, if black cherry will not be sufficiently  controlled, it can be expected that in a first phase black cherry will  dominate the understorey, that it will prevent the regeneration of all other  species and that, very soon, it will form an almost single-species dominated  stage in forest succession.

The early stages of spontaneous forest regeneration on poor soils and continental sand dunes in northern Belgium

1983 ◽  
Vol 49 ◽  
Author(s):  
M. Van Miegroet
Keyword(s):  
Scots Pine ◽  
Age Differences ◽  
Forest Regeneration ◽  
Sand Dunes ◽  
Mixed Forest ◽  
Pedunculate Oak ◽  
White Poplar ◽  
Technical Problems ◽  
Homogeneous Groups ◽  
Invading Species

Spontaneous  natural regeneration under variable conditions on sandy soils and continental  sand dunes were analysed in 5 locations in N.E. Belgium.     The number of seedlings varies between 14.000 and 522.000/ha. The most  prominent invading species are red oak, pedunculate oak and Scots pine.    Two principal types of regeneration are recognized : homogeneous groups of  oak or pine and mixtures, predominantly composed by the same species.  Pioneers such as birch, willow, white poplar and wild black cherry do not  play an important role.    Social differentiation sets in quite early and is mainly provoked by age  differences. Therefore early silvicultural intervention is advisable. The  growth relationships between the species indicate that Scots pine is not in  danger of spontaneous elemination by other species. Because of the density  and variability of spontaneous forest regeneration, the conversion of pure  pine stands into mixed forest, using group regeneration to this end, poses no  real technical problems.

scholarly journals Integrating Land-Cover Products Based on Ontologies and Local Accuracy

Information ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 236
Author(s):  
Ling Zhu ◽  
Guangshuai Jin ◽  
Dejun Gao
Keyword(s):  
Land Cover ◽  
Semantic Similarity ◽  
Mixed Forest ◽  
Global Scale ◽  
Semantic Mapping ◽  
Global Land Cover ◽  
Resolution Observation ◽  
Local Accuracy ◽  
Global Land ◽  
Broad Leaf

Freely available satellite imagery improves the research and production of land-cover products at the global scale or over large areas. The integration of land-cover products is a process of combining the advantages or characteristics of several products to generate new products and meet the demand for special needs. This study presents an ontology-based semantic mapping approach for integration land-cover products using hybrid ontology with EAGLE (EIONET Action Group on Land monitoring in Europe) matrix elements as the shared vocabulary, linking and comparing concepts from multiple local ontologies. Ontology mapping based on term, attribute and instance is combined to obtain the semantic similarity between heterogeneous land-cover products and realise the integration on a schema level. Moreover, through the collection and interpretation of ground verification points, the local accuracy of the source product is evaluated using the index Kriging method. Two integration models are developed that combine semantic similarity and local accuracy. Taking NLCD (National Land Cover Database) and FROM-GLC-Seg (Finer Resolution Observation and Monitoring-Global Land Cover-Segmentation) as source products and the second-level class refinement of GlobeLand30 land-cover product as an example, the forest class is subdivided into broad-leaf, coniferous and mixed forest. Results show that the highest accuracies of the second class are 82.6%, 72.0% and 60.0%, respectively, for broad-leaf, coniferous and mixed forest.

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