High yielding ruminant livestock require high nutritive value in forage for maintenance, growth and production. Climate change has been documented as impacting on the nutritive value of forage plants. Therefore, the aim of this study was to investigate the impact of increased temperature in combination with CO2-enhancement on the nutritive value of orchard grass (cocksfoot; Dactylis glomerata L.), as a C3 model plant, widespread in mountainous permanent grassland plant communities. Functional traits and forage quality of orchard grass were investigated both under ambient (C0T0) and under simulated, future climate conditions (C2T2) with increased temperature (+3°C) and enhanced CO2 concentration (+300 ppm) under field conditions. Plant samples were taken from each of the three growths over a period of three consecutive years and numerous functional properties and forage quality parameters were determined. Special attention was paid to the determination of water-soluble carbohydrates (WSC), crude protein (CP), non-protein N (NPN) and metabolizable energy (ME) as possible indicators for different climatic conditions. It is hypothesized that (i) functional traits and (ii) forage quality of orchard grass are altered by increased temperature and higher CO2 concentration. The results showed a negative impact of C2T2 compared to C0T0 on tiller height (54.4 v. 70.6 cm) and weight (2.42 v. 3.22 g) as average over cuts and years. The NPN content was lower in C2T2 (312 g/kg CP) compared to C0T0 (339 g/kg CP). In contrast, the WSC content was higher in C2T2 (90.3 g/kg DM) compared to C0T0 (82.5 g/kg DM). Both ME content and digestibility were increased in C2T2 (9.18 ME/kg DM and 68.2%) compared to C0T0 (8.86 ME/kg DM and 65.4%). Concluding, under increased temperature and enhanced CO2, both functional traits and certain nutrients and their fractions appear to change in orchard grass.

中文翻译：

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温度升高和CO2空气富集对永久性草地果园草（Dactylis glomerata）营养价值的影响

高产反刍家畜需要高营养价值的饲料来维持、生长和生产。气候变化已被记录为影响牧草的营养价值。因此，本研究的目的是研究温度升高与 CO2- 提高果园草（鸡脚草）的营养价值；肾小球藻L.)，作为C3模式植物，广泛分布于山地永久性草地植物群落中。在环境 (C0T0) 和模拟的未来气候条件 (C2T2) 下，随着温度升高 (+3°C) 和 CO2 增加，研究了果园草的功能性状和草料质量2现场条件下的浓度（+ 300 ppm）。在连续三年的时间内从三个生长中的每一个中采集植物样本，并确定了许多功能特性和草料质量参数。特别注意测定水溶性碳水化合物（WSC）、粗蛋白（CP）、非蛋白N（NPN）和代谢能（ME）作为不同气候条件的可能指标。假设 (i) 功能性状和 (ii) 果园草的草料品质因温度升高和 CO2 升高而改变2浓度。结果显示，与 C0T0 相比，C2T2 对分蘖高度（54.4五。70.6 厘米）和重量（2.42五。3.22 g) 作为平均减产和年份。与 C0T0 (339 g/kg CP) 相比，C2T2 (312 g/kg CP) 中的 NPN 含量较低。相比之下，与 C0T0 (82.5 g/kg DM) 相比，C2T2 (90.3 g/kg DM) 中的 WSC 含量更高。与 C0T0（8.86 ME/kg DM 和 65.4%）相比，C2T2 中的 ME 含量和消化率均有所增加（9.18 ME/kg DM 和 68.2%）。结论是，在温度升高和二氧化碳浓度升高的情况下2，功能性状和某些营养素及其分数在果园草中似乎都发生了变化。