ABSTRACT Creation of plant associations with maximum stability of yields in the regional ecological conditions for which they have been designed is key in modern agriculture. The present study aimed to investigate the impact of the environment on productivity and stability of six grass associations (red fescue, pure stand; red fescue and birdsfoot trefoil; red fescue, tall fescue and birdsfoot trefoil; red fescue and Kentucky bluegrass; red fescue, Kentucky bluegrass and alfalfa; red fescue, Kentucky bluegrass and birdsfoot trefoil) in four locations (mountain slope with eastern, western, northern and south-eastern facing direction). Methods of dispersion, regression and nonparametric analysis were used to evaluate the stability of the mixtures. According to the productivity during the 13-year study period and the calculated stability parameters, the triple mixture of red fescue, Kentucky bluegrass and alfalfa was the highest yielding mixture, but this mixture also manifested itself as unstable. The lower yielding mixed sward of red fescue and Kentucky bluegrass and the pure stand of red fescue were also distinguished by low adaptive ability. In the conditions of the Middle Balkan Mountains, the mixture of red fescue, tall fescue and birdsfoot trefoil was characterised to have the most favourable combination of productivity and ecological stability, and was considered suitable for growing in a wide range of environmental conditions. As a whole, the swards on the mountain slopes with eastern and south-eastern exposure were more productive but had low stability compared to those grown on western and northern exposure.

中文翻译：

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巴尔干山脉条件下草群的生态评估

摘要在其设计的区域生态条件下创建具有最大产量稳定性的植物群落是现代农业的关键。本研究旨在调查环境对六种草群（红羊茅，纯林；红羊茅和鸟足三叶草；红羊茅、高羊茅和鸟足三叶草；红羊茅和肯塔基兰草；红羊茅，肯塔基兰草和苜蓿；红羊茅、肯塔基兰草和鸟足三叶草）在四个位置（东、西、北和东南朝向的山坡）。使用离散、回归和非参数分析方法来评估混合物的稳定性。根据 13 年研究期间的生产力和计算的稳定性参数，红羊茅、肯塔基蓝草和苜蓿的三重混合物是产量最高的混合物，但这种混合物也表现出不稳定。红羊茅和肯塔基兰草的低产混合草和红羊茅纯林也以低适应能力为特征。在中巴尔干山脉的条件下，红羊茅、高羊茅和鸟足三叶草的混合物被认为具有最有利的生产力和生态稳定性组合，被认为适合在广泛的环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。肯塔基兰草和苜蓿是产量最高的混合物，但这种混合物也表现出不稳定。红羊茅和肯塔基兰草的低产混合草和红羊茅纯林也以低适应能力为特征。在中巴尔干山脉的条件下，红羊茅、高羊茅和鸟足三叶草的混合物被认为具有最有利的生产力和生态稳定性组合，被认为适合在广泛的环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。肯塔基兰草和苜蓿是产量最高的混合物，但这种混合物也表现出不稳定。红羊茅和肯塔基兰草的低产混合草和红羊茅纯林也以低适应能力为特征。在中巴尔干山脉的条件下，红羊茅、高羊茅和鸟足三叶草的混合物被认为具有最有利的生产力和生态稳定性组合，被认为适合在广泛的环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。红羊茅和肯塔基兰草的低产混合草和红羊茅纯林也以低适应能力为特征。在中巴尔干山脉的条件下，红羊茅、高羊茅和鸟足三叶草的混合物被认为具有最有利的生产力和生态稳定性组合，被认为适合在广泛的环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。红羊茅和肯塔基兰草的低产混合草和红羊茅纯林也以低适应能力为特征。在中巴尔干山脉的条件下，红羊茅、高羊茅和鸟足三叶草的混合物被认为具有最有利的生产力和生态稳定性组合，被认为适合在广泛的环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。高羊茅和鸟足三叶草具有生产力和生态稳定性的最佳组合，被认为适合在各种环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。高羊茅和鸟足三叶草具有生产力和生态稳定性的最佳组合，被认为适合在各种环境条件下生长。总体而言，与西部和北部暴露的山坡相比，东部和东南部暴露的山坡上的草丛生产力更高，但稳定性较低。