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1.
Naaf Tobias Feigs Jannis Till Huang Siyu Brunet Jörg Cousins Sara A. O. Decocq Guillaume De Frenne Pieter Diekmann Martin Govaert Sanne Hedwall Per-Ola Lenoir Jonathan Liira Jaan Meeussen Camille Plue Jan Vangansbeke Pieter Vanneste Thomas Verheyen Kris Holzhauer Stephanie I. J. Kramp Katja 《Landscape Ecology》2022,37(5):1365-1384
Landscape Ecology - Plant populations in agricultural landscapes are mostly fragmented and their functional connectivity often depends on seed and pollen dispersal by animals. However, little is... 相似文献
2.
Naaf Tobias Feigs Jannis Till Huang Siyu Brunet Jörg Cousins Sara A. O. Decocq Guillaume De Frenne Pieter Diekmann Martin Govaert Sanne Hedwall Per-Ola Helsen Kenny Lenoir Jonathan Liira Jaan Meeussen Camille Plue Jan Poli Pedro Spicher Fabien Vangansbeke Pieter Vanneste Thomas Verheyen Kris Holzhauer Stephanie I. J. Kramp Katja 《Landscape Ecology》2021,36(10):2831-2848
Landscape Ecology - Evidence for effects of habitat loss and fragmentation on the viability of temperate forest herb populations in agricultural landscapes is so far based on population genetic... 相似文献
3.
Enola Reintam Katrin Trükmann Jaan Kuht Edvin Nugis Liina Edesi Alar Astover 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(3):265-272
Abstract The weight of the tractor is not the only factor affecting soil compaction. Soil-management practices, such as the use of fertilizers and pesticides, also affect soil properties through an increased number of overriding. The aim of the current study was to investigate compaction effects on soil physical properties, such as dry bulk density and penetration resistance, and the growth of spring barley (Hordeum vulgare L.) as a monoculture. The five-year experiment was conducted on the Estonian University of Life Sciences’ research field at Eerika, near Tartu in 2001–2005. The soil of the experimental site is sandy loam Stagnic Luvisol. The treatments included were no compaction, one pass, three passes, and six passes. All passes were track-by-track. Measurements of soil and plant were made in the earing phase of barley and measurements of yield in the maturity phase of barley. The compaction treatment was conducted using an MTZ-82 tractor (total weight 4.84 Mg). Neither fertilizers nor herbicides were used. 5 years after compaction distinguishable subsoil and topsoil compaction was detected. Soil deformation increases with the number of passes; in the case of six passes soil bulk density increased by 0.15 Mg m?3 and penetration resistance by 3 MPa. However, there were no significant differences in the soil bulk density and penetration resistance between treatments compacted with one and three passes. The effect of compaction on soil bulk density was higher when the soil was compacted under wet conditions. Compaction decreased the quantity of barley shoots, their phytomass, and grain yield by more than 80%. In the second year of the experiment the dry weight of above ground biomass decreased by almost three times and shoots’ density by 1.5 times, compared with the first year results. In the third year of the experiment the biomass, plant density, and grain yield of barley were stabilized and no further decreases were detected in the following two experimental years. The results from the experiment revealed that even a low weight tractor can induce subsoil compaction and a high decrease of plant productivity by repeated passes over time. 相似文献
4.
Pallieter De Smedt Lander Baeten Willem Proesmans Matty P. Berg Jörg Brunet Sara A. O. Cousins Guillaume Decocq Marc Deconchat Martin Diekmann Emilie Gallet-Moron Brice Giffard Jaan Liira Ludmilla Martin Astra Ooms Alicia Valdés Monika Wulf Martin Hermy Dries Bonte Kris Verheyen 《Landscape Ecology》2018,33(3):407-421
Purpose
Most of the agricultural landscape in Europe, and elsewhere, consists of mosaics with scattered fragments of semi-natural habitat like small forest fragments. Mutual interactions between forest fragments and agricultural areas influence ecosystem processes such as nutrient cycling, a process strongly mediated by the macrodetritivore community, which is however, poorly studied. We investigated macrodetritivore distribution patterns at local and landscape-level and used a key functional trait (desiccation resistance) to gain mechanistic insights of the putative drivers.Methods
Macrodetritivores were sampled in forest edges-centres of 224 European forest fragments across 14 landscapes opposing in land use intensity. We used a multilevel analysis of variance to assess the relative contribution of different spatial scales in explaining activity-density and Shannon-diversity of woodlice and millipedes, together with a model-based analysis of the multivariate activity-density data testing the effect on species composition. Secondly, we tested if desiccation resistance of macrodetritivores varied across communities at different spatial scales using linear mixed effect models.Results
Forest edge-centre and landscape use intensity determined activity-density and community composition of macrodetritivores in forest fragments, while fragment characteristics like size and continuity were relatively unimportant. Forest edges and higher intensity landscapes supported higher activity-density of macrodetritivores and determined species composition. Forest edges sustained woodlouse communities dominated by more drought tolerant species.Conclusions
Landscape use intensity and forest edges are main drivers in macrodetritivore distribution in forest fragments with desiccation resistance a good predictor of macrodetritivore distribution. Key functional traits can help us to predict changes in community structure in changing landscapes.5.
在经过从母猪的单只圈养转变为群体饲养的初期阵痛后,许多养猪场在母猪生产上找到了新的平衡点,但是其他猪场似乎仍处于苦苦的挣扎之中。为了要取得良好的繁殖性能,使母猪远离应激是至关重要的。 相似文献
6.
Forest biodiversity conservation in intensively managed agricultural landscapes is a constant concern. The dispersal ability of forest plants is, hypothetically, the major limiting factor in fragmented forest landscapes and, therefore, we tested the validity of the theoretical dispersal scheme for plants in fragmented landscapes: ancient forest > woody corridor > emerging forest patch. To this end, we examined the distribution pattern of forest-dwelling plant species in rural landscapes, specifically the occurrence of common forest plant species in old historical forests and in closed-canopy stands of rural ornamental parks, planted on an agricultural land one–two centuries ago.We found that (i) the shade tolerant plant flora in parks’ stands more resemble forests than woody linear habitats (corridors), (ii) nearly 50% of the local forest species pool was present in parks, (iii) the abundance of seed source habitats and the ecological quality of the target habitat determine success rate of colonization. Models predicted that optimal stand characteristics for forest herbs are a minimum area 2.5 ha, canopy closure 0.7–0.8, basal area of trees 10–20 m2 ha?1 and the presence of moderate understory management.We conclude that only patch-type habitats provide suitable environmental conditions for forest-specific plant species. Many common forest plant species are capable of long-distance dispersal between habitat patches across hostile agricultural land, and accordingly, their dispersal follows a modified scheme of the island biogeography, without intermediary role of corridor habitats. Old rural manor parks provide an ecosystem service for nature conservation by harbouring forest biodiversity, and should be considered as potential refugium habitats. 相似文献
7.
Katri Ots Aigars IndriksonsIveta Varnagiryte-Kabasinskiene Malle MandreTatjana Kuznetsova Jaan KlõšeikoMari Tilk Kadri KõresaarAljona Lukjanova Karin Kikamägi 《Forest Ecology and Management》2011,262(2):82-87
Studies were carried out in 1999, 2005 and 2007 in the area of Kunda cement plant in Northeast Estonia on sample plots 3 km W and 2.5 and 5 km E of Kunda. As control stands, two plots for pine and spruce were established in Lahemaa National Park (34-38 km W of Kunda). The selected pine and spruce stands were 75-85-year-old Myrtillus site type, of 0.7-0.8 density and II quality class, with moderately dense or sparse understorey. The values concerning needle density and number of needle scars were higher for shoots formed in the period of higher pollution than for the shoots grown under a considerably lower pollution load. Although the cement dust pollution has notably decreased from year to year, the number of needle pairs per 1 cm of the shoot was 1.8-2.1 times greater in the shoots formed in 1998 than in those formed in 2003, whereas the changes were statistically reliable. Possibly the low temperatures at the time of shoot and needle formation affected the density of needles on all sample plots, and thus the number of needles on shoots formed in 2003 was many times smaller. After the significant fall in the pollution load since 1996 the length growth of needles intensified around Kunda cement plant, at the same time no changes occurred in the length growth of needles in the control area. As compared to the data from 1998, the length growth of pine needles had improved, especially 2.5 and 5 km E from the cement plant, needles being respectively 1.5 and 1.1 cm longer than 6 years ago. The stimulation of the growth of pine and spruce needles 2.5 and 5 km E of the cement plant may be a sign of a positive effect of reduced doses of cement dust in soil. The greater length of pine and spruce needles is the reason for the larger biomass of the needles. 相似文献
8.
Jaanus Paal Margit Turb Tiina Köster Elle Rajandu Jaan Liira 《Journal of Forest Research》2011,16(3):244-252
Decisions regarding forest typology, management and protection are often based on the structures of present-day forests, ignoring
their successional history. Forests growing on kames, eskers and various moraine hillocks common in regions with Holocene
glaciation are good examples of this approach. In Estonia, these forests locally persist as fragments of continuous primary
forest, but usually they are situated on former slash-and-burn areas (bushlands) or reforested agricultural land. Our aim
was to elucidate the strength of the effect of long-term land-use history on the present-day vegetation compositions of mature
hillock forests and their soil chemistry. It appeared that even the mature secondary hillock forests are still distinct from
historically continuous stands in terms of species composition. We discovered connections between stand history and species
content in hillock forests as well as transformed soil properties. The carbon and nitrogen contents in the humus horizons
of secondary forests are lower while their carbon–nitrogen ratios are higher than in continuous forests. The relationship
between vegetation and stand history is demonstrated by the higher proportions of anthropophytic and apophytic species in
the herb layer of the secondary forests. The presence of species that are tolerant of anthropogenic impact on the secondary
hillock forests floor can also be partly explained by the effect of different species in the tree and shrub layers, gaps in
the tree canopy, and the boundary effect caused by the small areas of forest patches, neighboring grasslands or fields. The
extinction debt in secondary communities should also be considered. 相似文献
9.
We focused our attention on quantifying the factor complex of forest regeneration in 423 mature and old stands with contrasting
environmental conditions. We recorded the microhabitat selection of tree recruits, the frequency of tree seedlings, and evaluated
the drivers of sapling abundance and diversity. The majority of forest regeneration was established on undisturbed forest
floor. Dead wood was a frequent substrate in spruce-(co)dominated forests. Seedling frequency within a stand was related to
the site-type specific productivity gradient of stands—pine seedlings were common in low-productivity and spruce in high-productivity
boreal forests. Seedlings of temperate broad-leaved trees dominated in productive boreonemoral forests, except for oak, which
showed a uniform distribution of abundance in all forest site-types. Sapling abundance was dictated by forest site-type, and
facilitated by stand diversity, variability in stand closure, lying dead wood, abundant moss, and a thick organic layer. Only
in boreal forests was sapling abundance suppressed by the abundant spruce and younger trees. Upon considering the relationship
between sapling abundance and species richness, sapling diversity was dependent on forest site-type, suppressed by stand density
and dead wood (old gap) abundance, and facilitated by stand diversity. In addition, boreonemoral stands, competition from
herbs, and facilitation by mosses occurred. The observed pattern of tree recruitment points to the importance of top-down
effects of the overstory, competing or facilitating interactions with forest floor vegetation, and availability of regeneration
microhabitats, which in complex make their ecology comparable with forest herbs. Natural forest regeneration can be enhanced
if silvicultural methods support mixed stands and enhance field layer diversity. Oak can provide the universal tree species
to improve stand structure over a wide range of habitats. 相似文献
10.