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1.
Landscape Ecology - Predicting habitat use patterns is a key issue in the management of large herbivore populations. Particularly, indicators providing a model of the spatial distribution of a...  相似文献   
2.
The main objective of this study was to find the best practice of inducing the sprouting of dormant potato tubers. We compared two protocols of breakage of dormancy, which are based on dipping excised potato eyes in an aqueous solution of gibberellic acid (GA3) and kinetin (standard 1) or in the aqueous solution of GA3, thiourea, and daminozide (standard 2), with a newly reported approach based on ethanol. We tested the effect of ethanol alone or in combination with GA3 and/or kinetin on dormancy release and sprouting of the potato tubers. As a model, we used two potato genotypes (cultivars Pasat and Dorota), with long dormancy of 5 and 10 weeks respectively. We showed that the standard 2 was the most effective treatment both for dormancy breaking and in promoting sprout growth, especially for cv. Dorota, for which the treatment induced 82.3% of tuber eye-plugs to sprout 28 days after treatment and to produce 93.2% of emerged plants after subsequent 28 days of cultivation in the greenhouse. For this cultivar, similar efficacy was observed for the combination of 4% ethanol with GA3 and kinetin. The same concentration of ethanol combined with GA3 but without kinetin was the most efficient treatment for breaking dormancy of cultivar Pasat. However, the difference between the various treatment combinations was statistically insignificant. Ethanol alone or in combination with kinetin poorly induced breakage of dormancy, confirming the main role of GA3 in artificial dormancy breaking. Thus our study showed that the standard 2 is the most effective approach for breakage of dormancy at least with long term-dormancy cultivars.  相似文献   
3.
  1. Spread of the crayfish plague pathogen, Aphanomyces astaci, by North American crayfish species is considered one of the main reasons for substantial declines and local extinctions of native European crayfish populations. Owing to human introductions, several American crayfish species have become established throughout the world, and thus pose a potential threat to indigenous crayfish populations susceptible to crayfish plague.
  2. In Japan, two such widespread alien species, Procambarus clarkii and Pacifastacus leniusculus, were introduced for aquaculture purposes in the late 1920s and since then successfully expanded their ranges.
  3. Aggressive interactions with alien crayfish along with habitat modifications have been considered primarily responsible for drastic declines in populations of the Japanese endemic crayfish, Cambaroides japonicus, observed in the last few decades. However, the presence of the crayfish plague pathogen, to which Japanese crayfish are susceptible, may be expected, and could contribute to these declines.
  4. Only recently, A. astaci has been reported from Taiwan, and to our knowledge no study focusing on its presence outside of the Western Palearctic has been conducted.
  5. To fill this gap, 54 P. clarkii and 47 P. leniusculus individuals from five different Japanese locations were screened using molecular methods recommended by the World Organization for Animal Health. Aphanomyces astaci DNA was detected in all studied populations, altogether in 61% and 21% of examined individuals of P. clarkii and P. leniusculus, respectively.
  6. The results provide the first evidence of A. astaci presence in Japan and highlight the threat of pathogen transmission to C. japonicus populations.
Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
4.
Journal of Soils and Sediments - This study analyzes the variability of sediment loads under variant climate change and land use scenarios in a Carpathian catchment with a dam reservoir. The areas...  相似文献   
5.
Väli  Ülo  Mirski  Paweł  Sein  Gunnar  Abel  Urmas  Tõnisalu  Grete  Sellis  Urmas 《Landscape Ecology》2020,35(7):1667-1681
Landscape Ecology - Biodiversity is closely related to landscape heterogeneity, but both are difficult to evaluate directly. Apex predators, such as raptors, are potential surrogate indicators of...  相似文献   
6.
Our previous study revealed the expression of substance P (SP) and calcitonin gene‐related peptide (CGRP) in sensory distal ganglion of the vagus (nodose ganglion) neurons in the pig. As these neuropeptides may be involved in nociception, the goal of these investigations was to determine possible expression of vasoactive intestinal polypeptide (VIP), SP and CGRP in the pituitary adenylate cyclase‐activating polypeptide‐immunoreactive (PACAP‐IR) porcine nodose perikarya. Co‐expression of these substances was examined using a double‐labelling immunofluorescence technique. To reveal the ganglionic cell bodies, the pan‐neuronal marker protein gene product 9.5 (PGP 9.5) was used. Quantitative analysis of the neurons revealed that 67.25% of the PGP 9.5+ somata in the right‐side ganglion and 66.5% in the left side, respectively, co‐expressed PACAP‐IR. Moreover, 60.6% of the PACAP‐IR cells in the right‐side ganglion and 62.1% in the left, respectively, co‐expressed VIP. SP‐IR was observed in 52.2 and 39.9% of the right and left ganglia, respectively. CGRP was found in 27.7 and 34.1% of the right and left distal ganglion of the vagus, respectively. High level of co‐expression of PACAP with VIP, SP and CGRP in the distal ganglia of the vagus sensory perikarya directly implicates studied peptides in their functional interaction during nociceptive vagal transduction.  相似文献   
7.
This article presents a validation of a method, proposed in Podlaski (2003), for estimating the degree of tree damage. This method belongs to a group of small-area methods. To estimate the degree of tree damage in individual P3 sub-blocks of the SINUS system of information on the natural environment, a classification based on the degree of defoliation was used. Spatial distribution of the degree of tree damage was estimated through unrestricted simple random sampling. The maximum total estimation error for proportions of fir and beech with a damage degree of zero, and also with second and third degrees jointly, reached a maximum of 35.6% for fir, and 33.8% for beech. P3 sub-blocks characterised by the highest proportion of the healthiest trees (at least 15% being undamaged trees) occurred in patches in the case of fir, and in larger, compact areas in the case of beech. Because spatial diversification in the health of fir, and to a smaller degree in the case of beech, occurs at small scales, small-area methods for estimating tree condition are necessary. An analogous scheme, combining small-area with large-area methods (utilising sub-blocks of the network of large-area systems in a small-area inventory, and establishing a common database), could be used on a wider scale; for example, by supplementing the program of estimating tree health carried out by the United Nations Economic Commission for Europe (Lorenz et al. 2002) with local inventories.  相似文献   
8.
Using eight populations of Scots pine growing in foothills of the Sudetes (southern Poland) as an example, the character and causes of annual ring variation in 1900–1999 were studied. The climate had a short-term effect on radial growth during the whole period investigated. A long-term decrease of radial growth occurred after 1960, but only in some localities. It was probably caused by non-climatic factors, most likely by industrial pollution. The decline of trees during that period is mainly evidenced by a high variation of width of annual rings, a small similarity of chronologies of annual ring widths, and a lack of signal years. After 1990, the tree recovery process was evident. It was most intensive in localities where the earlier stress was the most severe. Then, trees started to produce wide annual rings, homogeneity of the growth reaction increased, and the signal years began to occur.  相似文献   
9.
Dulling of high-speed steel (HSS) cutting tools after milling five wood species has been analyzed. The wood investigated varied in mineral contamination, high-temperature corrosivity (HTC) and density (D). Experiments performed proved that up to date methods for evaluation of mineral contamination in wood should be improved. A new pipe-like form of mineral contamination particles was evidenced. The correlation between the presence of 3D aggregates of silica in wood and high content of K and Ca in the ash was established. Employing multivariable theoretical simulation method, the combined effect of mineral contamination, HTC and wood density on the tool dullness appeared to be a reasonable explanation of the results obtained.  相似文献   
10.
Analytical studies were conducted on the species composition of galls occurring on the leaves of Salix purpurea L. in the Ojców National Park in 1999?–?2000. The species composition of galls was identical in two consecutive years. Galls were caused by 5?species (a total of 480?galls). The most numerous species in both years was Pontania viminalis (L.). Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Pontania dolichura (Thoms.) and P. viminalis (L.) in 1999 as well as Phyllocolpa leucaspis (Tischb.) and P. viminalis (L.) in 2000.  相似文献   
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