The impacts of agricultural payments on groundwater quality: Spatial analysis on the case of Slovenia

The European Common Agricultural Policy still follows its primary goals, i.e. quality food at affordable prices and a decent standard of living for farmers, fifty years after its adoption. Moreover, this policy adapts to the changing needs of society and the new challenges, mostly preservation of the environment, nature and biodiversity in rural areas. Although the Common Agricultural Policy receives the largest share of European budget, the funds are decreasing over time, especially direct payments, which aim to provide basic income support to farmers in the European Union. On the other hand, agri-environmental payments are gaining importance. Policy decision-makers should be interested in the question of impacts of growing eco-conditionality of agricultural spending. New insights would help them to be successful in achieving the goals of sustainable agriculture. The purpose of this paper is to estimate the impacts of production support payments and rural development payments on the quality of groundwater. We use the small EU country Slovenia as an example. The baseline indicators are the level of nitrates and pesticides in groundwater, while the impacts were estimated using spatial error model. The results show that direct payments, coupled subsidies and investment grants raise the level of pesticides in groundwater, but do not have any statistically significant impact on the level of nitrates in groundwater. Furthermore, we did not find any statistically significant effects of agri-environmental payments on decrease of groundwater pollution with nitrates. However, our findings revealed that agri-environmental payments are effective in reducing pesticides in groundwater, although only to a limited extent. These results imply a problem of insufficient targeting of agri-environmental measures on the one hand, and suggest that greening of direct payments is necessary and entirely justified.     

Quantitative evaluation of temporal similarity in abundance of animal species

Summary A quantitative method is suggested for measuring the similarity of seasonal abundance patterns of different animal species. The method was applied to two sets of field data and produced biologically meaningful and interesting results.     

Striking difference in response to expanding brood parasites by birds in western and eastern Beringia

Two species of obligate brood‐parasitic Cuculus cuckoos are expanding their ranges in Beringia. Both now breed on the Asian side, close to the Bering Strait, and are found in Alaska during the breeding season. From May to July 2017, we used painted 3D‐printed model eggs of two cuckoo host‐races breeding in northeastern Siberia to test behavioral responses of native songbirds on both sides of the Bering Strait, with particular attention to species that are known cuckoo hosts in their Siberian range. Each host nest was tested after the second egg was laid and, if possible, again 4 days later with a model of a different type. Although our Siberian study site was also outside the known breeding ranges of the cuckoos, we found that Siberian birds had strong anti‐parasite responses, with 14 of 22 models rejected. In contrast, birds in Alaska had virtually no detectable anti‐parasite behaviors, with only one of 96 models rejected; the rejecters were Red‐throated Pipits (Anthus cervinus). Such differences suggest that the cuckoos might successfully parasitize naïve hosts and become established in North America whether or not their historic host species are widely available.     

The effect of winter temperatures on the timing of breeding activity in the common toad Bufo bufo

A 19-year study of a common toad population in south Dorset, UK, was carried out between 1980 and 1998. The daily arrival of sexually mature male and female toads at a breeding pond was recorded each year. The timing of the main arrival of toads at the breeding pond was highly correlated with the mean daily temperatures over the 40 days immediately preceding the main arrival. When the temperatures were higher than average, breeding occurred significantly earlier in the year than if they were either average or lower than average. During the study, the toad breeding seasons were early (2–13 February) in 5 years (1989, 1990, 1993, 1995, 1998), late (16–23 March) in 2 years (1986, 1996) and average (25 February–8 March) during the remaining 12 years. Evidence was found suggesting that common toads have a daylength threshold of about 9 h, below which the migration to the breeding pond does not occur. Evidence was also found indicating that common toads in southern England have a threshold temperature for activity of about 6°C and that the onset of breeding activity is highly correlated with the number of days during the 40 days prior to the main arrival at the breeding pond that were at or above this temperature. Predicting the start of the main breeding migration to a pond in any year may be possible by comparing the pattern of the 40-day running mean daily temperatures from 21 December the preceding year with those from previous years when the start of breeding activity is known. Although all five of the earliest recorded toad breeding years occurred during the last 10 years, and were associated with the occurrence of particularly mild winters, a significant trend towards earlier breeding in recent years compared with previous years was not found. Received: 16 July 1998 / Accepted: 14 September 1998     

Differential climate–growth relationships in Abies alba Mill. and Fagus sylvatica L. in Mediterranean mountain forests

Pointer year analysis, simple correlations, and response functions were combined in a dendroecological study to evaluate climate–growth relationships over the last century in two Abies alba Mill. and Fagus sylvatica L. mixed stands in Southern Italy mountainous areas. Analyses revealed species-specific attributes at the two study sites, i.e. Molise and Basilicata. Growth divergence between the two species emerged based on three primary climatic drivers, including drought stress and spring warmer temperatures during the current growing season for F. sylvatica, and water availability in the previous growing season for A. alba. However, despite the microclimatic differences between the two study sites, F. sylvatica showed similar climate–growth patterns, while differences were indicated for A. alba, due to its minor susceptibility to drought stress during the current growing season at the Basilicata site. Indeed, at the southernmost geographic limits of A. alba drought avoidance mechanisms were confirmed, consistent with traits considered diagnostic for the species in the Mediterranean region.     

Ultrastructure of Pollen Grains from Forced and Unforced Shrubs of Common Lilac

Forcing makes possible to induce plant flowering independently of the season. In lilac, high temperature is the factor that breaks deep dormancy. The deepest dormancy occurs between the end of October and the end of December. Depending on the depth of dormancy, the starting temperatures required for forcing are 37°C in November, 31°C in December, and 25°C in January–March. Under natural conditions, the temperature inducing the inflorescence bud breaking is 6°C, whereas 9°C and 13°C or more allow inflorescence elongation and flowering, respectively (Kronenberg, 1994). In the present work, the effect of high temperature at the beginning of the forcing cycle on the structure of developing pollen grains of common lilac was investigated. Pollen grains from the outdoor-grown (control) shrubs showed no signs of degeneration. They were spherical, three-colpate to colporoidate, and bicellular, and contained large numbers of lipid bodies. High temperatures at the early forcing cycle (November) resulted in the degeneration of most microspores. The first signs of degeneration (cytoplasm plasmolysis) were observed at the tetrad stage and in mature anthers; the microspores consisted only of the outer and inner sporopolenin layers.     

Variation partitioning for range expansion of an introduced species: the common waxbill Estrilda astrild in Portugal

The common waxbill Estrilda astrild was first introduced to Portugal, from Africa, in 1964, from where it has spread to much of the country and to Spain. We modelled the expansion of this species on a 20×20-km UTM grid in 4-year periods from 1964 to 1999. Colonisation process on a grid was modelled as a function of several biophysical and spatio-temporal variables through the fitting of several multiple logistic equations. Variation partitioning confirmed the importance of the spatial-temporal component, explaining 33% of the total variation, followed by the combined effects of both environmental and spatial-temporal variables (around 25%). Only 11% of the total variation can be attributed strictly to the considered environmental factors.     

Characterization of fusarium wilt-resistant and fusarium wilt-susceptible somaclones of banana cultivar rastali (Musa AAB) by random amplified polymorphic DNA and retrotransposon markers

Two DNA fingerprinting techniques, random amplified polymorphic DNA (RAPD) and inter-retrotransposon amplified polymorphism (IRAP), were used to characterize somaclonal variants of banana. IRAP primers were designed on the basis of repetitive and genome-wide dispersed long terminal repeat (LTR) retrotransposon families for assessing the somaclonal variation in 2Musa clones resistant and susceptible toFusarium oxysporum f. sp.cubense race 4. RAPD markers successfully detected genetic variation within and between individuals of the clones. IRAP makers amplified either by a single primer or a combination of primers based on LTR orientation successfully amplified different retrotransposons dispersed in theMusa genome and detected new events of insertions. RAPD markers proved more polymorphic than IRAP markers. Somaclonal variation seems to be the result of numerous indels occurring genome-wide accompanied by the activation of retroelements, as a result of stress caused by micropropagation. It is concluded that characterization of the somaclonal variants requires more than one DNA marker system to detect variation in diverse components of the genome.     

香蕉果实成熟相关基因研究进展(综述)

本文从乙烯生物合成、呼吸作用、碳水化合物代谢、细胞壁降解及其它有关成熟的代谢过程等方面,概述与香蕉果实成熟相关的基因研究进展。     

斯洛维尼亚池塘中大蟾蜍的交配模式

为了解大蟾蜍( Bufo bufo)的配对成功是否与身体大小有关,在蟾蜍产卵之前,我们在斯洛文尼亚捕捉和测量了2 224只成体样本。在这些捕获的个体中, 1 772只为雄性, 452只为雌性,其中355对处于抱对状态。雌性的体长(从吻端到泄殖腔的距离)一般比雄性稍长。无论雄性还是雌性,抱对者的体长均大于未抱对者。抱对的雄性和雌性的体长具有显著的正相关。我们所发现的大小匹配的交配模式,与从其它普通蟾蜍种群得到的结果一致[动物学报51 (3) : 513 -515 , 2005]。