排序方式： 共有7条查询结果，搜索用时 15 毫秒
1
1.
Landscape Ecology - Fragmentation in agricultural landscapes is considered as a major threat to biodiversity. Thus, ecological corridors are deployed at multiple scales to increase connectivity.... 相似文献
2.
Uroy Léa Alignier Audrey Mony Cendrine Foltête Jean-Christophe Ernoult Aude 《Landscape Ecology》2021,36(9):2487-2504
Landscape Ecology - Landscape connectivity plays a key role in determining the persistence of species inhabiting fragmented habitat patches. In dynamic landscapes, most studies measure connectivity... 相似文献
3.
Aude Ernoult Yves Tremauville Pierre Margerie Didier Alard 《Biological conservation》2006,127(1):1-17
Changes in landscape pattern under the control of agriculture intensification are considered to be an important driver of biodiversity and often a threat for conservation. The response of species to landscape changes is complex, including possible time lags, and depends on the taxonomic group. The search for surrogate species or surrogate data for biodiversity is confronted with this complexity.This study was conducted on two taxonomic groups (birds and vascular plants) for 20 sites each of 1 km2 equally distributed in the Seine valley floodplain. For plants, two habitats were studied: grasslands and hedges. We used a generalised additive model (GAM) and co-inertia analyses to determine whether present or past landscape attributes can best explain the biodiversity components (structure and composition). This study confirms the major role of landscape pattern attributes for predicting some metrics of biodiversity, e.g. species richness. But this study shows that potential drivers of biodiversity come from both the past and present landscape patterns. The quality of surrogates for biodiversity is strongly dependent on understanding the importance of past conditions. This suggests the need for more functional surrogates, taking into account the situation of equilibrium or non-equilibrium between biodiversity and its drivers. 相似文献
4.
5.
The effect of solid fat (melting point 70°C) and liquid fat (melting point ‐20°C) on the microwave expansion of extruded glassy amylopectin pellets was investigated. Glassy, unexpanded amylopectin extrudates containing ≤10% fat were equilibrated at different water activity levels (aw) and then expanded by microwave heating. Expanded products were characterized by analyzing degree of expansion, structure, and texture. For the aw range studied, expansion increased with increasing aw of the pellets until a maximum at aw = 0.605 and then decreased. Completely dehydrated samples did not expand at all. This demonstrated that moisture was the driving force in the microwave expansion of the pellets. The addition of solid fat contributed greatly to expansion. The highest degree of expansion was obtained for pellets containing 6% solid fat at all aw levels. Due to the effect on expansion, the addition of solid fat also affected the microstructure and texture of the expanded products. Concentrations of solid fat >2% resulted in expanded products with a large number of cells, uniform in size, with thin cell walls. Liquid fat addition had a negative effect on microwave expansion. The expanded products obtained from pellets that contained liquid fat had a lower expansion volume and a coarser structure. 相似文献
6.
Aude Ernoult Sylviano Freiré-Diaz Estelle Langlois Didier Alard 《Landscape Ecology》2006,21(5):631-639
This landscape study was based on the sampling of 20 replicated landscape sites (1 km2 each) that were located within the floodplain of the river Seine. For each site, 13 landscape variables were measured at
three dates (1963–1985–2000). The aim of this study was to investigate the overall landscape variability through its different
dimensions (space vs. time) and to assess the relative importance of each dimension. We used a new statistical method, i.e.,
partial triadic analysis (PTA), which allowed us to assess both (1) the spatial variability of the floodplain landscape and
its dynamics in time and (2) the dynamic trajectories of the landscape variables for each site. The results showed, at the
floodplain scale, the same landscape pattern has emerged since 1963, although a major trend was observed which consisted in
a decrease in meadows resulting from an increase in arable crops. At the site scale, landscape sites, even if they were all
influenced by this general trend during the 40-year period, showed contrasting trajectories. These results suggest that similar
sites in 2000 do not necessarily share common histories and that contrasting sites in 2000 may have originated from similar
patterns in 1963. The issue of biodiversity surrogates is then discussed, suggesting that new landscape metrics should be
developed, emphasising spatial variability and (or) temporal dynamics. 相似文献
7.
1