The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.
Over the last fifty years, almost half of the steppe rangeland in the Central Anatolian Region of Turkey (CAR) has been converted to cropland without an equivalent reduction in grazing animals. This shift has led to heavy grazing pressure on rangeland vegetation. A study was initiated in June 2003 using 6 multiscale Modified-Whittaker plots to determine differences in plant composition between areas that have not been grazed in 27 years with neighboring grazed plant communities. A total of 113 plant species were identified in the study area with the ungrazed plots containing 32 plants more than the grazed plots. The major species were Astragalus acicularis, Bromus tomentellus, Festuca valesiaca, Genista albida, Globularia orientalis, Poa bulbosa, and Thymus spyleus ssp rosulans. Grazing impacts on forbs were more pronounced than for grasses and shrubs. Based on Jaccard's index, there was only a 37% similarity of plant species between the two treatments. Our study led to four generalizations about the current grazing regime and long-term exclosures in the steppe rangeland around the study area: (1) exclosures will increase species richness, (2) heavy grazing may have removed some plant species, (3) complete protection from grazing for a prolonged period of time after a long history of grazing disturbance may not lead to an increase in desirable plant species with a concomitant improvement in range condition, and (4) research needs to be conducted to determine how these rangelands can be improved.
In central Turkey, common vetch (Vicia sativa ssp. sativa) is traditionally grown in spring. Frequent droughts cause crop failures. Autumn sowing can give higher yields, but then winter plant death is a major problem. The objective of this research was to explore and quantify variation available in V. sativa ssp. germplasm for winter hardiness, yield and adaptability. Eleven plant characters were evaluated in 164 vetch populations in autumn and spring sowings over two years, and their inter-relationships were analyzed. Mean winter death was 27% and was greater in the second, colder year, though the magnitude of the coefficient-of-variation was similar in both years (27 and 28%). Autumn-sown plants produced more standing biomass (17%) than spring-sown plants. Winter death was strongly related to other characters, particularly in the colder year. Principle component analysis proved to be efficient at simplifying the results by classifying the eleven variables into three main groups on the basis of seed size, maturity and winter hardiness. There is wide, exploitable phenotypic variation, and enhanced adaptation for autumn sowing could be achieved by selecting for large seeds and early maturity combined with reasonable winter survival.Additional key words: common vetch, Pearson correlation, plant metric characters, principle component analysis, variety development, winter hardiness.
ResumenVariación fenotípica en poblaciones de veza (Vicia sativa ssp.) del centro de Turquía, sembradas en otoño y primavera La veza (Vicia sativa ssp. sativa) crece tradicionalmente en el centro de Turquía y las cosechas sufren pérdidas importantes en las frecuentes temporadas de sequía en primavera. La siembra en el otoño puede conducir a rendimientos más altos, pero las plantas pueden sufrir una mortandad elevada en el invierno, lo que representa un problema mayor. El objetivo de nuestra investigación fue explorar y cuantificar la variación para el vigor, el rendimiento y la adaptabilidad en una colección de germoplasma de V. sativa ssp. Se analizaron once caracteres vegetativos y sus inter-relaciones en 164 poblaciones de haba en siembras de otoño y primavera durante dos años. La mortalidad media en invierno fue un 27% superior en el segundo año, aunque la magnitud del coeficiente de variación fue similar en ambos años (27% y 28%). Las plantas sembradas en otoño produjeron más biomasa (17%) que las de primavera. La mortalidad registrada en invierno estuvo fuertemente relacionada con otros caracteres, particularmente con el índice de heladas anual. El análisis de componentes principales demostró su eficiencia para la simplificación y clasificación de las once variables en tres grupos principales sobre la base del tamaño de la muestra, madurez y resistencia al frío. Existe una amplia variación aprovechable y se demuestra la posibilidad de incrementar la adaptación en la siembra de otoño, con una razonable supervivencia en invierno, mediante la selección de plantas con semillas de mayor tamaño y madurez temprana Palabras clave a...
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