The emissions of isoprenoids, a kind of biogenic volatile organic compounds (BVOCs), from soils is not well characterized. We quantified the exchange of isoprenoids between soil with litter and atmosphere along a horizontal gradient from the trunks of the trees, in a Mediterranean Pinus pinea plantation with dry and green needle litter to open herbaceous turf during mornings at mid-summer. Further, potential associated drivers were identified. Isoprenoid emissions were greatest and most diverse, and also can be roughly estimated by litter dry weight near the trunk, where the needle litter was denser. The composition of emitted isoprenoid by needle litter was different than the composition previously described for green needles. Low exchange rates of isoprenoids were recorded in open turf. Isoprenoid exchange rates were correlated positively with soil temperature and negatively with soil moisture. Given the variations in ground emissions with soil, vegetation, microorganisms, and associated interactions, we recommend widespread extensive spatio-temporal analysis of ground level BVOC exchanges in the different ecosystem types.

中文翻译：

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地中海草皮中与松树相关的地面类异戊二烯交换

从土壤中排放的类异戊二烯（一种生物挥发性有机化合物（BVOC））的排放尚未得到很好的表征。我们在地中海松树的松树中，通过树木树干的水平梯度，定量了土壤与凋落物和大气之间的类异戊二烯交换。在夏季仲夏早晨，用干燥的绿色针叶树种开草皮。此外，确定了潜在的相关驱动因素。类异戊二烯的排放量最大，种类最多，也可以通过树干周围的凋落物干重粗略估算，那里的针状凋落物较密。针刺释放出的类异戊二烯的成分与先前针对生针所描述的成分不同。在开阔的草坪上，异戊二烯的交换率低。类异戊二烯交换速率与土壤温度呈正相关，与土壤水分呈负相关。考虑到地面排放物随土壤，植被，微生物和相关相互作用的变化，我们建议对不同生态系统类型的地面BVOC交换进行广泛的时空分析。