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981.
Despite the widely accepted idea that shaded plantations are valuable habitats for Neotropical migrants in disturbed landscapes, little empirical evidence is available in relation to the quality of this habitat for Neotropical-Nearctic migratory birds in the Andes. We evaluated the suitability of shaded plantations for overwintering Neotropical-Nearctic migratory birds by examining diurnal and seasonal variation in body condition of migrants in these agroforests in the Andes. During October to April 2008–2009 and 2009–2010, we mist-netted eight species of Neotropical-Nearctic migrants in shaded plantations in the Colombian Andes. Body condition improved throughout the day for Cerulean Warbler (Setophaga cerulea), Blackburnian Warbler (Setophaga fusca), Tennessee Warbler (Leiothlypis peregrina), and especially Canada Warbler (Cardellina canadensis). Similarly, body condition improved across the season for Tennessee Warbler, Rose-breasted Grosbeak (Pheucticus ludovicianus), and Summer Tanager (Piranga rubra). Our results provided additional evidence that several common Neotropical migrants, including species of conservation concern such as Cerulean Warbler and Canada Warbler, may improve their body condition in shaded plantations. However, about half of the species assessed in this study did not show any significant improvement in their body condition (e.g. Red-eyed Vireo). Furthermore, on average, species were in poor condition (i.e. body condition scores were negative) in these coffee farms. Thus, the extent to which this agricultural system represents high quality habitat should be looked with caution. Overall, our data contribute novel information on daily patterns of body condition improvement for several common migratory birds in Andean shaded plantations. 相似文献
982.
Matthias Vanmaercke Willem Maetens Jean Poesen Benediktas Jankauskas Genovaite Jankauskiene Gert Verstraeten Joris de Vente 《Journal of Soils and Sediments》2012,12(4):586-602
Purpose
This study aims to understand better the relationship between measured soil loss rates due to sheet and rill erosion (SL), predicted SL rates and measured catchment sediment yields (SY) in Europe. 相似文献983.
Joan Marull Carme Font Enric Tello Nofre Fullana Elena Domene Manel Pons Elena Galán 《Landscape Ecology》2016,31(2):317-336
Context
The role of agricultural landscapes in biodiversity conservation is an emerging topic in a world experiencing a worrying decrease of species richness. Farm systems may either decrease or increase biological diversity, depending on land-use intensities and management.Objectives
We present an intermediate disturbance-complexity model (IDC) of cultural landscapes aimed at assessing how different levels of anthropogenic disturbance on ecosystems affect the capacity to host biodiversity depending on the land matrix heterogeneity. It is applied to the Mallorca Island, amidst the Mediterranean biodiversity hotspot.Methods
The model uses the disturbance exerted when farmers alter the Net Primary Production through land-use change as well as when they remove a share of it (HANPP), together with Shannon–Wiener index (H′) of land-cover diversity. The model is tested with a twofold-scalar experimental design (1:50,000 and 1:5000) of a set of landscape units along three time points (1956, 1989, 2011). Species richness of breeding and wintering birds, taken as a biodiversity proxy, is used in an exploratory factor analysis.Results
The results clearly show that when intermediate levels of HANPP are performed within intermediate levels of complexity (H′) in landscape patterns, like agro-forest mosaics, great bird species richness and high socio-ecological resilience can be maintained. Yet, these complex-heterogeneous landscapes are currently vanishing due to industrial farm intensification, rural abandonment and urban sprawl.Conclusions
The results make apparent the usefulness of transferring the concept of intermediate disturbance-complexity interplay to cultural landscapes. Our spatial-explicit IDC model can be used as a tool for strategic environmental assessment of land-use planning.984.
We conducted a study to find out if arbuscular mycorrhizal (AM) fungi (Acaulospora scrobiculata, Scutellospora calospora) and phosphate solubilizing bacteria (PSB, Paenibacillus polymyxa) inoculation either individually or in combinations can improve Acacia auriculiformis seedling growth, uptake of nutrients and quality in a phosphorus deficient tropical Alfisol. The seedlings were assessed for various growth and nutrient uptake parameters after 60 days of treatment. Inoculation with P. polymyxa stimulated mycorrhizal formation. Seedling height, stem girth, taproot length, number of leaves and leaf area, plant dry matter production, nodulation, and nodular dry weight were significantly higher for seedlings that were either dual inoculated or triple inoculated compared to individual inoculation of AM fungi or PSB, and uninoculated seedlings. Dual and triple application of AM fungi and PSB also significantly improved the nutrient contents of shoots and roots and nutrient uptake efficiencies. The calculated seedling quality indexes of the AM fungi and PSB inoculated seedling were 25–208% higher than uninoculated seedlings. These findings show that A. auriculiformis seedlings when dual inoculated or triple inoculated performed better than seedlings inoculated with the microbes individually and compared with uninoculated control seedlings. We conclude that bioinoculation is important for the production of high-quality A. auriculiformis seedlings in tree nurseries for planting in nutrient deficient soils. 相似文献
985.
María López-Martín Marta Velasco-Molina Heike Knicker 《Journal of Soils and Sediments》2016,16(2):360-370
Purpose
Fire in mountainous areas can lead to increased variability of their soil organic matter (SOM) due to spatial inhomogeneity and pre-fire fuel distribution. Here, we elucidated if this was the case in our study area and how this affected the reliability of solid-state 13C NMR spectroscopy applied for the study of the medium-term impact of fire on SOMMaterials and methods
The study occurred in the Sierra de Aznalcóllar, Southern Spain, which experienced their last intense fire 7 years before sampling. In a first approach (method 1), the corners and the center of a randomly chosen square with a side length of 15 m were sampled and analyzed separately. For comparison, composite samples (method 2) were obtained from three soils. We characterized material from unburnt, burnt, and double burnt regions. Data describing the physical and chemical properties of the soils together with the NMR spectroscopic characterization were analyzed using ANOVA.Results and discussion
Both sampling methods yielded comparable results with comparable standard errors. No major differences between the fire-affected and unburnt soils were observed with respect to physical and chemical properties and C and N contents, but solid-state 13C NMR spectroscopy indicated a small but significant elevation of aromaticity in the soils with fire history.Conclusions
The analysis showed that sampling with reduced replicates (method 1) can still lead to representative NMR data. The more complex sampling of comparing three composite samples (method 2) did not decrease the standard error. Our results also indicate that in the study area typical properties of the soil and its SOM induced by former burnings will not persist beyond a few decades.986.
Jorge Durán Alexandra Rodríguez José María Fernández-Palacios Antonio Gallardo 《Biology and Fertility of Soils》2009,45(7):781-788
The concern that climate change may increase fire frequency and intensity has recently heightened the interest in the effects
of wildfires on ecosystem functioning. Although short-term fire effects on forest soils are well known, less information can
be found on the long-term effects of wildfires on soil fertility. Our objective was to study the 17-year effect of wildfires
on forest net mineralization rates and extractable inorganic nitrogen (N) and phosphorus (P) concentrations. We hypothesize
that (1) burned forest stands should exhibit lower net mineralization rates than unburned ones; (2) these differences would
be greatest during the growing season; (3) differences between soil variables might also be observed among plots from different
years since the last fire; and (4) due to fire-resistant geochemical processes controlling P availability, this nutrient should
recover faster than N. We used a wildfire chronosequence of natural and unmanaged Pinus canariensis forests in La Palma Island (Canary Islands). Soil samples were collected during winter and spring at 22 burned and unburned
plots. We found significantly higher values for net N mineralization and extractable N pools in unburned plots. These differences
were higher for the winter sampling date than for the spring sampling date. Unlike extractable N and N mineralization rates,
extractable P levels of burned plots exhibited a gradual recovery over time after an initial decrease. These results demonstrate
that P. canariensis forest soils showed low resilience after wildfires, especially for N, and that this disturbance might induce long-term changes
in ecosystem functioning. 相似文献
987.
Experiments were performed in 2D terraria to investigate the burrowing behaviour of different earthworm species from various
ecological categories in single- and multi-species assemblages. The burrowing behaviour was quantified using image analysis
software during a 2-week period. Terraria were found to reveal realistic impressions of the burrowing behaviour of various
species according to the ecological classification of Bouché into epigeic, endogeic and anecic species. Results of the study
also permit the recommending of classifying various earthworms as intermediate species, e.g. Aporrectodea longa as endo-anecic and Lumbricus rubellus as epi-endogeic. Burrowing activity of endogeic species was significantly reduced in multi-species compositions compared
to single-species treatments. Moreover, burrowing activity of Octolasion tyrtaeum was significantly reduced in the presence of Lumbricus terrestris compared to the specific single treatment. This endogeic species profited from the burrowing behaviour, e.g. bioturbation,
of L. terrestris, and as such this is circumstantial evidence for commensalism (species interaction, in which one partner benefits while the
other is unaffected) between anecic and endogeic earthworm species. Simultaneous burrowing activity of a combined assemblage
of both endogeic species, Aporrectodea caliginosa and O. tyrtaeum, was also significantly reduced compared with the particular single treatments. Thus, this seems likely to be a response
of interspecific competition and trophic niche separation between endogeic species. 相似文献
988.
Teodora Ivanova Mihail Chervenkov Tatyana Stoeva Stoyan Chervenkov Yulia Bosseva Almira Georgieva Elina Tsvetanova Albena Alexandrova Dessislava Dimitrova 《Genetic Resources and Crop Evolution》2018,65(5):1349-1357
Allium siculum Ucria is a perennial bulbous plant that occurs in Bulgaria as A. siculum subsp. dioscoridis (Sm.) K. Richt. The plant is locally known as “samardala”. Its herbage is used traditionally by local communities in Bulgaria as edible green and for preparation of salty spice mixtures. The study was focused on the documentation of traditional knowledge about samardala, covering local collection and cultivation practices, processing methods and consumption preferences. The respondents (aged 30–86 years, 50% over 65) were local producers and small-scale salesmen of the herbage and samardala-containing spices. To assess the health features of samardala spices the total phenol and flavonoid content was measured in home-consumed or marketed flavoured salts. Overall appreciation of the plant and related food products was found to be very high; presenting a considerable engagement of the locals in plant cultivation and gathering, laborious processing and consumption. Traditional ecological knowledge about the biology, phenology and ecology of the samardala plant and methods for its processing is still preserved by elderly people who rely mostly on their own cultivated plants. Although the introduction of modern appliances has altered the method of production, its main stages and the recipes are preserved. Modernization of the processing method has not affected the quality of the products and faster processing could be a contributing factor for the higher content of biologically active substances. Phenolic content was about twice as low as the flavonoid content, following the same pattern for all tested flavoured salts. Measures for better management of natural populations and promotion of cultivation practices of A. siculum subsp. dioscoridis would ensure the sustainable quality of traditional products as well as conservation of the natural plant resources. 相似文献
989.
Hiromichi Mitamura Keiichi Uchida Yoshinori Miyamoto Nobuaki Arai Toshiharu Kakihara Takashi Yokota Junichi Okuyama Yuuki Kawabata Tohya Yasuda 《Fisheries Science》2009,75(5):1133-1140
Several species of fish exhibit strong homing ability and distinct site fidelity to their original habitats and spawning sites.
We have studied the homing ability, site fidelity, and diel movement patterns of three nocturnal black rockfish Sebastes inermis. The patterns were studied by radio-linked acoustic positioning system (VRAP) and fixed monitoring receivers (VR2) in Maizuru
Bay, Japan from June to July 2004. All tagged fish were displaced by 80–120 m, but they returned to their respective captured
sites at dusk, regardless of the time of release. The fish tagged with a depth sensor transmitter displayed active vertical
movement just after the release, and subsequently swam near the bottom depth around the captured site. After homing, they
displayed small home ranges [average 815 ± 265 m2 (SD)] around a single rocky area with one or two core areas (average 64 ± 30 m2). One core area was utilized during the daylight and dark periods, whereas the other was used primarily during the dark period.
The depth-tagged fish primarily used the depth of the rock crevice during the daylight, and it spent its dark period between
the surface and the deeper bottom depth. 相似文献
990.
Muh Ali Arsyad Takashi Akazawa Chie Nozaki Makoto Yoshida Kenichi Oyama Tatsuo Mukai Masahiro Ogawa 《Fish physiology and biochemistry》2018,44(5):1299-1308
Olive leaf is known to have the high polyphenol content of 6–9% in dry weight. We investigated the effects of olive leaf powder (OLP) supplemented to fish feed on muscle protein of red sea bream (Pagrus major). Fish reared with feed containing 8% OLP for 40 days had 1.4 times higher myofibril content and 2.2 times higher acid-soluble collagen content than fish reared with control feed for the same period. On the other hand, sarcoplasmic protein content and collagenase activity of the muscle were almost the same between the control fish and OLP-diet fish. Microstructure observation of fish muscle showed that OLP-diet fish has more rigid endomysium structure than that of the control-diet fish. Since collagen fiber in endomysium is responsible for the texture of the muscle, feeding OLP to aquaculture fish will lead to a harder muscle texture. The present study suggests that OLP is a useful feed additive to enhance the texture of aquaculture red sea bream muscle through strengthening of the collagen structure in the muscle. 相似文献