[en] The current structure of forests in Germany and their related biological diversity is a result of the natural, cultural and economic development of the last 10,000 years. The species composition, their distribution and the forest-field land proportion probably began to change about 3,000 years ago. Modern forestry evolved between 1750 and 1850 in Germany. The over-exploited and degenerated forests of that time were changed into highly productive pure conifer plantations. Solely by this measure, the increased demands of the timber using industries were satisfied. The proportion of natural pine forest in the potential natural vegetation is less than 3 % whereas the proportion of Scots pine in the current forest area is 28 %. The centre of distribution of these forests is the northern lowland regions of Germany where predominantly pure pine plantations occur on sites of natural hardwood forests. The age class structure is dominated by young stands up to 60 years old. This age class distribution complicates a cost-effective pine forestry. Within the last decades, alternative silvicultural regimes have been developed to solve these problems and to increase the degree of naturalness in existing pine plantations. In general these models aim to decrease costs, produce large and high quality timber, increase the structural diversity, increase the proportion of broadleaved species and of continuous cover forest systems. Diversity does not apply as an ecological quality criterion. For the assessment of the actual biodiversity a comparison with the potential natural vegetation is necessary.

[es] La estructura actual de los bosques en Alemania y su diversidad biol&oacute;gica relacionada es un resultado del desarrollo natural, cultural y econ&oacute;mico de los &uacute;ltimos 10.000 a&ntilde;os. La composici&oacute;n de especies, su distribuci&oacute;n, y la proporci&oacute;n de bosques-tierras agrarias empez&oacute; a cambiar probablemente hace unos 3.000 a&ntilde;os. La selvicultura moderna se desarroll&oacute; en Alemania entre 1750 y 1850. Los bosques sobre-explotados y degenerados de ese tiempo se cambiaron a plantaciones puras de con&iacute;feras altamente productivas. Gracias a esta medida se satisfizo el incremento de la demanda de madera de las industrias. La proporci&oacute;n de bosques naturales de pinos en la vegetaci&oacute;n potencial forestal es menos del 3 % mientas que la proporci&oacute;n de Pino silvestre en la superficie forestal actual es del 28 %. El centro de distribuci&oacute;n de esos bosques son las regiones bajas del norte de Alemania, donde existen predominantemente plantaciones puras de pinos en sitios de bosques naturales de frondosas. La estructura de las clases de edad est&aacute; dominada por rodales j&oacute;venes de hasta 60 a&ntilde;os de edad. Esta estructura de edades complica la existencia de una selvicultura rentable. Durante las &uacute;ltimas d&eacute;cadas se han desarrollado tratamientos selv&iacute;colas alternativos para solucionar estos problemas y para incrementar el grado de naturalidad de las plantaciones de pino existentes. En general, estos modelos buscan disminuir los costes, producir madera mayor y de m&aacute;s calidad, incrementar la diversidad estructural, incrementar la proporci&oacute;n de frondosas y conseguir una cubierta continua de los sistemas forestales. La diversidad no se constituye como un criterio ecol&oacute;gico de calidad. Para la evaluaci&oacute;n de la biodiversidad real se necesita una comparaci&oacute;n con la vegetaci&oacute;n potencial natural.