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1

The effect and implication of human disturbances on altitudinal variation of non-structural carbohydrates in Kobresia pygmaea

100%
Zhao Z., Zhang Y., Chen T., Cui X., Wu Q., An L.
Acta Physiologiae Plantarum
|
2014
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tom 36
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nr 09
Non-structural carbohydrates in plant organs can mirror the plant overall carbon supply status and balance and can also provide evidence for their health evaluation in the ecosystem. Non-structural carbohydrates in Kobresia pygmaea, one dominant herbaceous species on the Qinghai-Tibetan Plateau, were measured to investigate altitudinal variation in non-structural carbohydrate accumulations, as well as engineering disturbance on the stability of the alpine grassland ecosystem. An increasing trend with elevation in total soluble sugars, fructose, and sucrose was detected in the K. pygmaea growing in both undisturbed and disturbed sites. However, there were higher amounts and a more distinctly altitudinal trend of non-structural carbohydrates with a minor fluctuation in undisturbed sites compared to disturbed sites. In addition, the altitudinal trend of sucrose is similar to that in sucrose phosphate synthase and sucrose synthase activities, while it is opposite to that in neutral invertase and soluble acid invertase activities, suggesting that the sucrose accumulation was primarily related to its synthesis. These results revealed that human disturbance resulted in a reduced carbon supply and altered the balance of carbohydrate utilization in plants on the Qinghai-Tibetan Plateau.
2

Flight behaviour and observability in human-disturbed sika deer

100%
Borkowski J.
Acta Theriologica
|
2001
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tom 46
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nr 2
Sika deer Cervus nippon Temminck, 1838 observability and flight behaviour were studied in an area with a high level of human disturbance (Tanzawa Mts, Japan). Deer observation rate was positively affected by habitat-related food conditions, while it was negatively correlated with the number of tourists in the study area. Flight frequency in April-September was lower than in October-February. It was also influenced by period of day, behaviour of investigator and deer group size. Group composition, deer activity and habitat condition had no effect on flight frequency. Thus, only 317 (48%) of the deer groups encountered were caused to flee and among them as many as 86% fled for a distance shorter than 40 m. It was concluded that deer in Tanzawa Mts learned to tolerate people, what is known for the populations which are unhunted or under low hunting pressure.
3

Land use and land cover change in protected areas: using remote sensing to survey suitable habitats of brown bear Ursus arctos

84%
Farashi A., Parvian N., Najafabadi M. S.
Polish Journal of Ecology
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2016
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tom 64
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nr 3
In recent years, brown bear Ursus arctos populations in Iran have experienced a clear trend of reduction and the species is now officially listed as threatened under provincial legislation. Anthropogenic habitat alteration and increasing human access to previously remote landscapes are potential source of stress for this species in Iran. Therefore, land cover changes in the Chelcheli protected area were mapped for 1991–2013 using time sequential Landsat TM and ETM at 30 meters resolution. Moreover, Maximum entropy (MaxEnt) modeling was used to investigate habitat selection of brown bear. The results showed that suitable patches overlapped with forest areas (Hyrcanian forest) and rivers. Our results also indicate that the brown bear habitat suitability is negatively influenced by human disturbance (e.g., roads, settlements). Increased human disturbance in brown bear habitat in recent decades may cause bears to avoid the disturbed areas. Therefore, the management plans should focus on reducing the human infrastructures around brown bear habitat. A suggestion is to place the core secure areas for brown bear inside the suitable habitat close to rivers where the human access is restricted. Promoting awareness of biodiversity conservation among tourism should also be one of the major focuses of management plans.
4

Habitat preferences of Caucasian rock agama Paralaudakia caucasia (Sauria: Agamidae) in urban and natural habitats in Northeastern Iran

84%
Hosseinian Yousefkhani S. S., Aliabadian M., Zuffi M. A. L.
Polish Journal of Ecology
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2018
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tom 66
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nr 1
In this study, we chose 61 plots along three randomly placed transects in urban and natural areas to examine Paralaudakia caucasia habitat preferences. Ten habitat characteristics found to affect the lizard occurrence were recorded in both habitat types. Based on ANOVA, distance to farmland, height of vegetation cover, percentage of cover of human structures, and slope orientation are significantly different between presence and absence plots. Using Principal Component Analysis, we found that the distance to farmland was the main factor predicted species presence in natural habitats. In urban habitats, the percentage of human structures was more important than other factors in predicting P. caucasia presence. The species is more abundant in regions with a low percentage of human-made structures. Other informative factors for species presence were distance from farmland and distance between refuges for urban and natural populations, respectively. Urban populations of P. caucasia appear to prefer areas outside of the city center, far from human structures, whereas natural populations appear to prefer areas away from villages where they may find higher densities of safe refuges. Isolated rocks in both urban and natural areas have an important role in predicting species presence acting because they act as refuges.
5

Habitat factors and the presence or absence of otters Lutra lutra in Denmark

84%
Madsen A. B., Prang A.
Acta Theriologica
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2001
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tom 46
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nr 2
The purpose of the present study was to examine the relative influence of different habitat factors on otters Lutra lutra (Linnaeus, 1758) and to develop a predictive model to better understand the distribution of the otter in Denmark. During the National Otter Survey in 1991 data were collected on 19 variables which reflected aspects of habitat structure, composition, organic pollution and human disturbance. Multiple logistic regression analysis was used to estimate probabilities of the presence of otters as a function of one or more explanatory variables. Six variables (county, pH, water depth, presence of trees, bottom substrate and Saprobien-Index) were identified. In Denmark, otter habitat typically consists of water courses with depths > 1 m over a varied bottom, with pH > 7.0, Saprobien-Index on II-III to III (indicating slight organic pollution) with no trees on the banks. Some of these variables reflect highly productive waters. The use of the otter as an indicator of good water quality and/or aquatic habitat should be used with care.
6

Behavioural adaptation of Talitrus saltator populations to beaches with different dynamics and degree of human disturbance along Tunisian coasts

84%
El Gtari M., Charfi-Cheikhrouha F., Marchetti G., Scapini F.
Polskie Archiwum Hydrobiologii
|
2000
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tom 47
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nr 3-4
7

Does hydro-electric project development causes land use-land cover change at landscape level? A case study of temperate forest of Western Himalaya

67%
Jolli V.
Journal of Water and Land Development
|
2012
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nr 16
8

Reactions to human disturbances in an urban population of the Swan Goose Anser cygnoides in Heidelberg [SW Germany]

67%
Randler C.
Acta Ornithologica
|
2003
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tom 38
|
nr 1
9

Does size matter? Relating consumed prey sizes and diet composition of otters in South Iberian coastal streams

59%
Clavero M., Prenda J., Delibes M.
Acta Theriologica
|
2007
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tom 52
|
nr 1
We analysed seasonal changes in the sizes of prey [grey mullets (Mugilidae), flatfish (Soleidae), eelAnguilla anguilla and crayfishProcambarus clarkii] consumed by ottersLutra lutra Linnaeus, 1758 in a Mediterranean-climate coastal area and relate them to the frequencies of occurrence of each prey species in otter diet. The sizes of over 1500 otter prey were estimated from measurements of key pieces found in 814 otter spraints, which were collected in lower stream stretches in a sandy coastal area. Clear relationships between mean prey size and frequency of occurrence were observed for the four prey types. These relationships were positive for grey mullets, flatfish and crayfish (ie they occurred more in otter diet when more large individuals were predated), but was negative in the case of eels. Results suggest that these patterns could be related to seasonal changes in habitat use. Previous works in the study area showed that otter concentrate its predation efforts in freshwater stream stretches during spring and summer, when more and larger crayfish are available. Freshwater stretches have neither grey mullets nor flatfish, while eels are larger and scarcer there than near streams’ mouths, where crayfish is absent.
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