An assessment of the causes and consequences of agricultural land abandonment in Europe

ABSTRACT

The agriculture sector is the principal source of income for around 20% of the EU-26 population, which live in predominantly rural regions that would be devastated without its contribution. Moreover, the combined agricultural and food sector forms an important part of the EU economy, accounting for 15 million jobs (8.3% of total employment) and 4.4% of GDP. The 12 million active farmers across Europe today, have an average farm size of about 15 ha, and are expected to meet the needs of 500 million Europeans. In addition, they are also expected to promote a sustainable and balanced development of their land, also in areas where production conditions are difficult. Yet, despite the relevance of the sector, the use of land for agriculture purposes is not very sustainable. Among other issues, there is a serious problem in respect of the abandonment of agricultural land. Based on the perceived need for research on this topic, the aim of this paper is to examine the causes and consequences of agricultural land abandonment, outlining its social, economic and environmental impacts, as well as the implications for territorial integration.     

Multimodal signaling in the Small Torrent Frog (Micrixalus saxicola) in a complex acoustic environment

Many animals use multimodal (both visual and acoustic) components in courtship signals. The acoustic communication of anuran amphibians can be masked by the presence of environmental background noise, and multimodal displays may enhance receiver detection in complex acoustic environments. In the present study, we measured sound pressure levels of concurrently calling males of the Small Torrent Frog (Micrixalus saxicola) and used acoustic playbacks and an inflatable balloon mimicking a vocal sac to investigate male responses to controlled unimodal (acoustic) and multimodal (acoustic and visual) dynamic stimuli in the frogs’ natural habitat. Our results suggest that abiotic noise of the stream does not constrain signal detection, but males are faced with acoustic interference and masking from conspecific chorus noise. Multimodal stimuli elicited greater response from males and triggered significantly more visual signal responses than unimodal stimuli. We suggest that the vocal sac acts as a visual cue and improves detection and discrimination of acoustic signals by making them more salient to receivers amidst complex biotic background noise.     

From metamorphosis to maturity in complex life cycles: equal performance of different juvenile life history pathways

Performance in one stage of a complex life cycle may affect performance in the subsequent stage. Animals that start a new stage at a smaller size than conspecifics may either always remain smaller or they may be able to "catch up" through plasticity, usually elevated growth rates. We study how size at and date of metamorphosis affected subsequent performance in the terrestrial juvenile stage and lifetime fitness of spadefoot toads (Pelobates fuscus). We analyzed capture-recapture data of > 3000 individuals sampled during nine years with mark-recapture models to estimate first-year juvenile survival probabilities and age-specific first-time breeding probabilities of toads, followed by model selection to assess whether these probabilities were correlated with size at and date of metamorphosis. Males attained maturity after two years, whereas females reached maturity 2-4 years after metamorphosis. Age at maturity was weakly correlated with metamorphic traits. In both sexes, first-year juvenile survival depended positively on date of metamorphosis and, in males, also negatively on size at metamorphosis. In males, toads that metamorphosed early at a small size had the highest probability to reach maturity. However, because very few toadlets metamorphosed early, the vast majority of male metamorphs had a very similar probability to reach maturity. A matrix projection model constructed for females showed that different juvenile life history pathways resulted in similar lifetime fitness. We found that the effects of date of and size at metamorphosis on different juvenile traits cancelled each other out such that toads that were small or large at metamorphosis had equal performance. Because the costs and benefits of juvenile life history pathways may also depend on population fluctuations, ample phenotypic variation in life history traits may be maintained.     

Linking atmospheric circulation to daily precipitation patterns over the territory of Bulgaria

An eight states non-homogeneous hidden Markov model is developed for linking daily precipitation amounts data at a network of 32 stations broadly covering the territory of Bulgaria to large-scale atmospheric patterns. At each site a 40-year record 1960?C2000 of daily October?CMarch precipitation amounts is modeled. The atmospheric data consists of daily sea-level pressure, geopotential height at 500 and 850?hPa, air temperature at 850?hPa and relative humidity at 700 and 850?hPa on a 2.5?×?2.5 grid based on NCEP-NCAR reanalysis data set covering the Europe-Atlantic sector 30W?C60E, 20N?C70N for the same period. The first 30?years data are used for model fitting purposes while the remaining 10?years are used for model evaluation. Detailed model validation is carried out on various aspects. The proposed model reproduces well the rainfall statistics for the observed and reserved data whereas the identified states are found to be physically interpretable in terms of regional climatology.     

Nutzen und Grenzen von Modellökosystemen zur Erfassung der Wirkung von Schadstoffen auf benthische Lebensgemeinschaften

The aim of this short article is to deliver insight into the prospects and constraints of model ecosystems in the assessment of effects of contaminants on benthic communities, especially the meiofauna. Numerous substances accumulate in sediments and thus a complex contamination exists which is able to impair benthic organisms. Besides direct effects, indirect effects are of importance and should be considered. Changes in competition and predator-prey-relationships lead to a variety of effects in the benthic food web that cannot be explained by direct toxicity of contaminants. In this article two microcosm studies, one with the heavy metal cadmium and one with the veterinary pharmaceutical Ivermectin, are presented which both showed direct as well as indirect effects. A significant change in abundance and composition of the meiofauna community has been observed. The prediction of field-effects of a certain substance as well as the interpretation of field data are the aims of model ecosystems. Both studies proofed that the investigation of meiofauna in microcosms is a promising tool to achieve these aims. Furthermore, microcosms with meiofauna might be able to assist the effect-directed analysis (EDA) in a risk assessment by identifying the effect-causing contaminants of complex environmental samples.     

Measurement of sustainability performance in Brazilian organizations

In recent years, sustainability issues are gaining greater prominence among organizations and their stakeholders around the world. This paper aims to verify the sustainability performance of Brazilian organizations in performance measures and to propose sustainable guidelines with the intention of directing future efforts to the transition to sustainable development. The research utilized a triangulated approach by collecting qualitative and quantitative data acquired through multiple collection methods of a theoretical literature review, documentary analysis of corporate reports, questionnaire survey and semi-structured interviews with industry professionals and academic researchers. The results show that internal organizational factors are the main inductors of the sustainable environment in organizations, and sustainability must be tied to strategic planning, starting from upper management to lower levels. It is essential to use sustainable performance measurement systems in order to respond to external and internal levers and serve as benchmarking for future corporate operations and strategies. In addition, it is the responsibility of organizations to focus their efforts on environmental protection, reduction of energy, corporate reputation, quality management, customer satisfaction and investor relations, as they are considered to be more important and have a relationship of dependence on organizational sustainability. The findings will be of value to professionals and academics who want to start measuring and for continuously improving the sustainability performance of their organizations according to the technical, economic, environmental, social and governance dimensions. This research work also helps to understand the perceptions and expectations of stakeholders.     

Reinvigorating the sustainable development research agenda: the role of the sustainable development goals (SDG)

The United Nations Sustainable Development Goals (UN SDGs) contain a set of 17 measures to foster sustainable development across many areas. It offers a good opportunity to reinvigorate sustainable development research for two main reasons. First, it comprises many areas of SD research, which have become mainstream thanks to the UN SDGs. Second, the fact that the UN and its member countries have committed to attaining SDGs by 2030 has added a sense of urgency to the need to perform quality research on SD on the one hand, and reiterates the need to use the results of this research on the other. Even though the basic concept of sustainability goes back many centuries, it has only recently appeared on the international political agenda. This is partly due to an awakening of the fact that the human ecological pressure on the planet is still much larger than what nature can renew or compensate for. Based on this state of affairs, this paper presents an outline of the process leading to the agreement on the UN SDGs, and looks at some of the ecological aspects as a result of continued pressure of human activities on natural resources. Furthermore, a set of research needs is proposed – also based holistically on updated research trends – discussing the degree of urgency of some measures and explaining why the UN SDGs need to be accorded greater priority in international sustainable development research efforts.     

Variation in pelagic larval growth of Atlantic billfishes: the role of prey composition and selective mortality

Atlantic blue marlin (Makaira nigricans) and sailfish (Istiophorus platypterus) larvae were collected from 10 monthly cruises (June–October 2003 and 2004) across the Straits of Florida to test (1) whether growth differed between the more productive western region near the Florida shelf, and the less productive eastern region toward the Bahamas, and (2) whether growth was related to prey consumption. Examination of larval sagittal otoliths revealed that instantaneous growth and daily growth during the first 2–3 weeks of life did not vary significantly between the two regions for either species. However, recent growth during the last two full days prior to collection was greater in the west for blue marlin larvae. Recent growth of blue marlin larvae <9 mm SL (primarily zooplanktivorous) was significantly related to prey composition (faster growth when higher proportions of Farranula copepods were consumed). Western larvae grew faster and had higher proportions of Farranula in their guts. Trends for sailfish larvae were not significant. In both species, comparison of early growth between <9 and ≥9 mm SL size groups indicated that growth trajectories diverged around 5–8 mm SL, the time when billfish larvae become capable of piscivory. Significantly faster growth of larger (older) larvae suggests that mortality was selective for fast growers and that the transition to piscivory may be a critical point in the early life of billfish.     

Incorporating covariates into fisheries stock assessment models with application to Pacific herring.

We present a framework for evaluating the cause of fishery declines by integrating covariates into a fisheries stock assessment model. This allows the evaluation of fisheries' effects vs. natural and other human impacts. The analyses presented are based on integrating ecological science and statistics and form the basis for environmental decision-making advice. Hypothesis tests are described to rank hypotheses and determine the size of a multiple covariate model. We extend recent developments in integrated analysis and use novel methods to produce effect size estimates that are relevant to policy makers and include estimates of uncertainty. Results can be directly applied to evaluate trade-offs among alternative management decisions. The methods and results are also broadly applicable outside fisheries stock assessment. We show that multiple factors influence populations and that analysis of factors in isolation can be misleading. We illustrate the framework by applying it to Pacific herring of Prince William Sound, Alaska (USA). The Pacific herring stock that spawns in Prince William Sound is a stock that has collapsed, but there are several competing or alternative hypotheses to account for the initial collapse and subsequent lack of recovery. Factors failing the initial screening tests for statistical significance included indicators of the 1989 Exxon Valdez oil spill, coho salmon predation, sea lion predation, Pacific Decadal Oscillation, Northern Oscillation Index, and effects of containment in the herring egg-on-kelp pound fishery. The overall results indicate that the most statistically significant factors related to the lack of recovery of the herring stock involve competition or predation by juvenile hatchery pink salmon on herring juveniles. Secondary factors identified in the analysis were poor nutrition in the winter, ocean (Gulf of Alaska) temperature in the winter, the viral hemorrhagic septicemia virus, and the pathogen Ichthyophonus hoferi. The implication of this result to fisheries management in Prince William Sound is that it may well be difficult to simultaneously increase the production of pink salmon and maintain a viable Pacific herring fishery. The impact can be extended to other commercially important fisheries, and a whole ecosystem approach may be needed to evaluate the costs and benefits of salmon hatcheries.