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1.
Science ; 382(6674): 982-983, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38033060

RESUMEN

8000 years ago-long before farming arrived-people in Siberia built defensive structures.


Asunto(s)
Caza , Humanos , Granjas/historia , Siberia , Caza/historia
2.
Science ; 377(6609): 908-909, 2022 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-36007048

RESUMEN

Studies seek clues to origins of farming, early languages.


Asunto(s)
Civilización , ADN Antiguo , Granjas , Lenguaje , Civilización/historia , Granjas/historia , Historia Antigua , Humanos , Lenguaje/historia , Medio Oriente
4.
Sci Rep ; 12(1): 1736, 2022 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-35110637

RESUMEN

In the USA, historical data on the period over which industrial swine farms have operated are usually only available at the county scale and released every 5 years via the USDA Census of Agriculture, leaving the history of the swine industry and its potential legacy effects on the environment poorly understood. We developed a changepoint-based workflow that recreates the construction timelines of swine farms, specifically by identifying the construction years of swine manure lagoons from historical Landsat 5 imagery for the period of 1984 to 2012. The study focused on the Coastal Plain of North Carolina, a major pork-producing state in the USA. The algorithm successfully predicted the year of swine waste lagoon construction (+ /- 1 year) with an accuracy of approximately 94% when applied to the study area. By estimating the year of construction of 3405 swine waste lagoons in NC, we increased the resolution of available information on the expansion of swine production from the county scale to spatially-explicit locations. We further analyzed how the locations of swine waste lagoons changed in proximity to water resources over time, and found a significant increase in swine waste lagoon distances to the nearest water feature across the period of record.


Asunto(s)
Crianza de Animales Domésticos/historia , Granjas/historia , Industria de Alimentos/historia , Carne de Cerdo , Sus scrofa , Animales , Monitoreo del Ambiente/historia , Historia del Siglo XX , Historia del Siglo XXI , North Carolina , Aguas del Alcantarillado , Factores de Tiempo , Eliminación de Residuos Líquidos/historia
5.
PLoS One ; 14(12): e0225555, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31826001

RESUMEN

Declines in agricultural biodiversity associated with modern farming practices may negatively affect the sustainability of agro-ecosystems, but formal knowledge of historical variation in spatio-temporal variation of agro-biodiversity is limited. We used time series of national (1947-2014) and district-level (1956-2008) crop distribution data for India to show that despite strong agricultural intensification after 1960, the average crop species diversity at the district level was stable, but increased at the country-level. While there was a decline in diversity in the major rice and wheat producing regions of northwestern India, associated with intensification of the production of these crops, diversity in western and southern India increased due to expansion of oilseeds and horticultural crops that replaced millet and sorghum. These opposite, but related, trends in crop-level diversity at the sub-national level partially canceled each other out at national level, but there nevertheless was a noticeable increase in overall crop diversity in India during this time period. Our results illustrate how patterns of change in crop diversity need to be considered at different levels of aggregation, and how a decrease in diversity associated with intensification and specialization in one area, may be associated with increased diversity elsewhere, and that support for intensive agriculture with relatively low crop diversity in some regions may be associated with an increase in crop diversity in other regions and at a higher level of aggregation.


Asunto(s)
Biodiversidad , Producción de Cultivos/estadística & datos numéricos , Productos Agrícolas/historia , Grano Comestible/historia , Producción de Cultivos/historia , Producción de Cultivos/métodos , Granjas/historia , Granjas/estadística & datos numéricos , Geografía , Historia del Siglo XX , Historia del Siglo XXI , India , Mijos , Oryza , Sorghum , Análisis Espacio-Temporal , Triticum
6.
Science ; 365(6457)2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31488661

RESUMEN

By sequencing 523 ancient humans, we show that the primary source of ancestry in modern South Asians is a prehistoric genetic gradient between people related to early hunter-gatherers of Iran and Southeast Asia. After the Indus Valley Civilization's decline, its people mixed with individuals in the southeast to form one of the two main ancestral populations of South Asia, whose direct descendants live in southern India. Simultaneously, they mixed with descendants of Steppe pastoralists who, starting around 4000 years ago, spread via Central Asia to form the other main ancestral population. The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the distinctive features shared between Indo-Iranian and Balto-Slavic languages.


Asunto(s)
Pueblo Asiatico/genética , Granjas/historia , Migración Humana/historia , Población/genética , Asia Central , Asia Sudoriental , Flujo Génico , Historia Antigua , Humanos , Irán , Análisis de Secuencia de ADN
7.
Science ; 363(6432)2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30872490

RESUMEN

Linguistic diversity, now and in the past, is widely regarded to be independent of biological changes that took place after the emergence of Homo sapiens We show converging evidence from paleoanthropology, speech biomechanics, ethnography, and historical linguistics that labiodental sounds (such as "f" and "v") were innovated after the Neolithic. Changes in diet attributable to food-processing technologies modified the human bite from an edge-to-edge configuration to one that preserves adolescent overbite and overjet into adulthood. This change favored the emergence and maintenance of labiodentals. Our findings suggest that language is shaped not only by the contingencies of its history, but also by culturally induced changes in human biology.


Asunto(s)
Evolución Biológica , Fuerza de la Mordida , Industria de Procesamiento de Alimentos/historia , Lingüística/historia , Sobremordida/historia , Acústica del Lenguaje , Antropología , Fenómenos Biomecánicos , Granjas/historia , Conducta Alimentaria , Manipulación de Alimentos , Historia Antigua , Humanos , Labio/anatomía & histología , Mandíbula/anatomía & histología , Maxilar/anatomía & histología , Sobremordida/epidemiología , Sonido , Diente/anatomía & histología
8.
Artículo en Inglés | MEDLINE | ID: mdl-30022018

RESUMEN

During the last 40 years, the quantity and spatial patterns of farmland in Western Jilin have changed dramatically, which has had a great impact on soybean production potential. This study used one of the most advanced crop production potential models, the Global Agro-Ecological Zones model, to calculate the soybean production potential in Western Jilin based on meteorological, topography, soil and land use data, and analyzed the impact of farmland change on soybean production potential during 1975⁻2013. The main conclusions were the following: first, the total soybean production potential in Western Jilin in 2013 was 8.92 million tonnes, and the average soybean production potential was 1612 kg/ha. The production potential of eastern area was higher than the other areas of Western Jilin. Second, farmland change led to a growth of 3.30 million tonnes in soybean production potential between 1975 and 2000, and a decrease of 1.03 million tonnes between 2000 and 2013. Third, taking account of two situations of farmland change, the conversion between dryland and other categories, and the change of irrigation percentage led to the total soybean production potential in Western Jilin increased by 2.31 and only 0.28 million tonnes respectively between 1975 and 2000, and increased by 0.12 and 0.29 million tonnes respectively between 2000 and 2013. In general, the increase of soybean potential production was mainly due to grassland and woodland reclamation. The results of this study would be a good guideline for protecting safe baseline of farmland, managing land resources, and ensuring continuity and stability of soybean supply and food security.


Asunto(s)
Producción de Cultivos/historia , Producción de Cultivos/tendencias , Granjas/historia , Granjas/tendencias , Glycine max , China , Producción de Cultivos/estadística & datos numéricos , Granjas/estadística & datos numéricos , Predicción , Historia del Siglo XX , Historia del Siglo XXI
10.
Artículo en Inglés | MEDLINE | ID: mdl-27571087

RESUMEN

Understanding the processes of historical land-use change is crucial to the research of global environmental sustainability. Here we examine and attempt to disentangle the evolutionary interactions between land-use change and its underlying causes through a historical lens. We compiled and synthesized historical land-use change and various biophysical, political, socioeconomic, and technical datasets, from the Qing dynasty to modern China. The analysis reveals a clear transition period between the 1950s and the 1980s. Before the 1950s, cropland expanded while forested land diminished, which was also accompanied by increasing population; after the 1980s land-use change exhibited new characteristics: changes in cropland, and decoupling of forest from population as a result of agricultural intensification and globalization. Chinese political policies also played an important and complex role, especially during the 1950s-1980s transition periods. Overall, climate change plays an indirect but fundamental role in the dynamics of land use via a series of various cascading effects such as shrinking agricultural production proceeding to population collapse and outbreaks of war. The expected continuation of agricultural intensification this century should be able to support increasing domestic demand for richer diets, but may not be compatible with long-term environmental sustainability.


Asunto(s)
Agricultura/historia , Cambio Climático/historia , Conservación de los Recursos Naturales/historia , Agricultura Forestal/historia , China , Granjas/historia , Bosques , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI
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