Climatic change and contemporaneous land-use phases north and south of the Alps 2300 BC to 800 AD

Fluctuations in the Δ14C curve and subsequent gaps of archaeological findings at 800–650 and 400–100 BC in western and central Europe may indicate major climate-driven land-abandonment phases. To address this hypothesis radiocarbon-dated sediments from four lakes in Switzerland were studied palynologically. Pollen analysis indicates contemporaneous phases of forest clearances and of intensified land-use at 1450–1250 BC, 650–450 BC, 50 BC–100 AD and around 700 AD. These land-use expansions coincided with periods of warm climate as recorded by the Alpine dendroclimatic and Greenland oxygen isotope records. Our results suggest that harvest yields would have increased synchronously over wide areas of central and southern Europe during periods of warm and dry climate. Combined interpretation of palaeoecological and archaeological findings suggests that higher food production led to increased human populations. Positive long-term trends in pollen values of Cerealia and Plantago lanceolata indicate that technical innovations during the Bronze and Iron Age (e.g. metal ploughs, scythes, hay production, fertilising methods) gradually increased agricultural productivity. The successful adoption of yield-increasing advances cannot be explained by climatic determinism alone. Combined with archaeological evidence, our results suggest that despite considerable cycles of spatial and demographic reorganisation (repeated land abandonments and expansions, as well as large-scale migrations and population decreases), human societies were able to shift to lower subsistence levels without dramatic ruptures in material culture. However, our data imply that human societies were not able to compensate rapidly for harvest failures when climate deteriorated. Agriculture in marginal areas was abandoned, and spontaneous reforestations took place on abandoned land south and north of the Alps. Only when the climate changed again to drier and warmer conditions did a new wide-spread phase of forest clearances and field extensions occur, allowing the reoccupation of previously abandoned areas. Spatial distribution of cereal cultivation and growth requirements of Cerealia species suggest that increases in precipitation were far more decisive in driving crop failures over central and southern Europe than temperature decreases.

Integration of a World Heritage Site in an agricultural environment in the Simen Mountains (Ethiopia)

The conflict between nature-orientated conservation and man-orientated rural development is examined, along with the degree to which ecological research contributes to mountain development, and whether conservation areas can be protected from being areas of natural resources ultimately to be used by man in life-threatening need. A high mountain national park in Ethiopia is taken as an example within UNESCO's concept of Biosphere Reserves. The main finding is that conservation without development will fail, and therefore the focus is more on the area surrounding a national park than on the park itself. A buffer zone must be developed as an economically stable and socially secure area for man, so that his needs do not drive him to exploit the last natural resource area in his vicinity. Simen is a World Heritage Site for future generations. Man and nature, development and conservation, belong together in this unique mountain area.

Agricultural biodiversity strengthening livelihoods in periurban Hyderabad, India

In periurban Hyderabad, India, leafy vegetables are increasingly grown along the Musi River and sold in urban markets. This agricultural biodiversity can significantly help urban and periurban farmers become more resilient to the impacts of such changes.

Linking soil properties and pre-Columbian agricultural strategies in the Bolivian lowlands: The case of raised fields in Exaltación

This paper aims to further our understanding of pre-Columbian agricultural systems in the Llanos de Moxos, Bolivia. Three different types of raised fields co-existing in the same site near the community of Exaltación, in north-western Beni, were studied. The morphology, texture and geochemistry of the soils of these fields and the surrounding area were analysed. Differences in field design have often been associated with the diversity of cultural practices. Our results suggest that in the study area differences in field shape, height and layout are primarily the result of an adaptation to the local edaphology. By using the technology of raised fields, pre-Columbian people were able to drain and cultivate soils with very different characteristics, making the land suitable for agriculture and possibly different crops. This study also shows that some fields in the Llanos de Moxos were built to prolong the presence of water, allowing an additional cultivation period in the dry season and/or in times of drought. Nevertheless, the nature of the highly weathered soils suggests that raised fields were not able to support large populations and their management required long fallow periods.

Plant species decline due to abandonment of meadows cannot easily be reversed by mowing. A case study from the southern Alps

Abstract. We resumed mowing in two plots of ca. 100 m2 in an abandoned meadow dominated by Brachypodium pinnatum on the slope of Monte Generoso (Switzerland). We monitored species composition and hay yield using point quadrats and biomass samples. Species frequencies changed little during 10 yr (1988–1997) while hay yields showed large fluctuations according to mean relative humidity in April-June. We performed a seed-addition experiment to test whether the establishment of meadow species is limited by lack of diaspores or favourable microsites for germination and recruitment from the seed bank. We sowed ca. 12 000 seeds of 12 species originating from a nearby meadow individually in plots of a 4 × 6 unbalanced Latin square with four treatments, burning, mowing, mowing and removal of a layer of decayed organic matter, and a control. We monitored the fate of seedling individuals for 24 months. Seedlings of all species were established and survived for 12 months, 10 species survived during at least 24 months, some reached a reproductive stage. Species responded to different qualities of microsites provided by the different treatments thus required different regeneration niches. Spontaneous long-distance immigration was insignificant. We conclude that the former species composition of abandoned meadows cannot easily be restored by mowing alone because many plant species of meadows do not have persistent seed banks and immigration over distances of more than 25 m and successful establishment is very unlikely.

Agricultural Productivity in the Early Ottoman Empire

This paper provides standardized estimates of labor productivity in arable farming in selected regions of the early Ottoman Empire, including Jerusalem and neighboring districts in eastern Mediterranean; Bursa and Malatya in Anatolia; and Thessaly, Herzegovina, and Budapest in eastern Europe. I use data from the tax registers of the Ottoman Empire to estimate grain output per worker, standardized (in bushels of wheat equivalent) to allow productivity comparisons within these regions and with other times and places. The results suggest that Ottoman agriculture in the fifteenth and sixteenth centuries had achieved levels of labor productivity that compared favorably even with most European countries circa 1850.

Factors that influence the decision to produce exportables in the Chilean agricultural sector

This study analyzes there lative importance of the factors that influence the decision to produce for foreign markets in the Chilean agricultural sector. Using data obtained from personal interviews with 368 farmers, the market/production decision was estimated using a multinomial logit model. Three market/production alternatives were analyzed: production aimed for the external market, production for the internal market but with expectations of being exported, and production targeted only for the internal market. Marginal effects, odds ratios and predicted probabilities were used to identify the relevance of each variable. The results showed that a producer that is male, with a higher educational level, that does not own the land, but rents it, whose farm has irrigation and is located in an area that has a high concentration of exporting producers, will have a high probability of producing exportables. However, the factor that has the highest impact on producing for the external market is the geographic concentration of exporting producers, that is, an export spillover effect. Indeed, when the concentration change from 0 to its maximum (0.26), the odds of producing exportables rather than producing traditional products increases by a factor of 70 (against a factor of 10 in the case of irrigation).

Producción y rentabilidad en la ganadería argentina. 1980-2006

El presente trabajo tiene como objetivo principal estudiar y analizar la producción y rentabilidad de la ganadería argentina. El trabajo intentará explorar si los vaivenes de la actividad se encuentran atados a la evolución de la economía en su conjunto, y del sector agropecuario en particular; o si por el contrario, se trata de un sector cuya senda ha logrado independizarse del resto de las actividades. En arreglo a lo dicho, se buscará dar cuenta del impacto de las políticas económicas y los cambios tecnológicos sobre la producción y rentabilidad del sector, prestando especial atención a cuestiones estructurales de la actividad como son la productividad, cantidad, localización y concentración del stock vacuno. Asimismo, y en relación a esta última variable, estudiaremos su incidencia sobre los pequeños, medianos y grandes productores. Para llevar a cabo dicho estudio, se analizará con especial atención lo acontecido a partir de 2002, intentando rescatar las rupturas y continuidades que supuso el abandono de la convertibilidad.

Mapping decadal land cover changes in the woodlands of north eastern Namibia using the Landsat satellite archive (1975-2014)

Woodland savannahs provide essential ecosystem functions and services to communities. On the African continent, they are widely utilized and converted to intensive land uses. This study investigates the land cover changes of 108,038 km**2 in NE Namibia using multi-temporal, multi-sensor Landsat imagery, at decadal intervals from 1975 to 2014, with a post-classification change detection method and supervised Regression Tree classifiers. We discuss likely impacts of land tenure and reforms over the past four decades on changes in land use and land cover. These changes included losses, gains and exchanges between predominant land cover classes. Exchanges comprised logical conversions between woodland and agricultural classes, implying woodland clearing for arable farming, cropland abandonment and vegetation succession. The most dominant change was a reduction in the area of the woodland class due to the expansion of the agricultural class, specifically, small-scale cereal and pastoral production. Woodland area decreased from 90% of the study area in 1975 to 83% in 2014, while cleared land increased from 9% to 14%. We found that the main land cover changes are conversion from woodland to agricultural and urban land uses, driven by urban expansion and woodland clearing for subsistence-based agriculture and pastoralism.

Producción y rentabilidad en la ganadería argentina. 1980-2006

El presente trabajo tiene como objetivo principal estudiar y analizar la producción y rentabilidad de la ganadería argentina. El trabajo intentará explorar si los vaivenes de la actividad se encuentran atados a la evolución de la economía en su conjunto, y del sector agropecuario en particular; o si por el contrario, se trata de un sector cuya senda ha logrado independizarse del resto de las actividades. En arreglo a lo dicho, se buscará dar cuenta del impacto de las políticas económicas y los cambios tecnológicos sobre la producción y rentabilidad del sector, prestando especial atención a cuestiones estructurales de la actividad como son la productividad, cantidad, localización y concentración del stock vacuno. Asimismo, y en relación a esta última variable, estudiaremos su incidencia sobre los pequeños, medianos y grandes productores. Para llevar a cabo dicho estudio, se analizará con especial atención lo acontecido a partir de 2002, intentando rescatar las rupturas y continuidades que supuso el abandono de la convertibilidad.

Producción y rentabilidad en la ganadería argentina. 1980-2006

El presente trabajo tiene como objetivo principal estudiar y analizar la producción y rentabilidad de la ganadería argentina. El trabajo intentará explorar si los vaivenes de la actividad se encuentran atados a la evolución de la economía en su conjunto, y del sector agropecuario en particular; o si por el contrario, se trata de un sector cuya senda ha logrado independizarse del resto de las actividades. En arreglo a lo dicho, se buscará dar cuenta del impacto de las políticas económicas y los cambios tecnológicos sobre la producción y rentabilidad del sector, prestando especial atención a cuestiones estructurales de la actividad como son la productividad, cantidad, localización y concentración del stock vacuno. Asimismo, y en relación a esta última variable, estudiaremos su incidencia sobre los pequeños, medianos y grandes productores. Para llevar a cabo dicho estudio, se analizará con especial atención lo acontecido a partir de 2002, intentando rescatar las rupturas y continuidades que supuso el abandono de la convertibilidad.