CAREER: Using an Urban-to-Rural Gradient as a Proxy for Global Change Effects on Selected Biosphere-Atmosphere Trace Gas Exchanges

总体目标是调查生物源挥发性有机化合物(BVOC)排放对温度和湿度等气候参数变化的响应。BVOC的排放，特别是异戊二烯的排放，对大气化学产生重要的直接影响，对气候产生间接影响。在气候变暖的情况下，BVOC排放增加可能会加剧区域臭氧污染，加剧全球变暖。然而，由于对植物BVOC的生产和排放对气候变化的适应能力缺乏了解，未来BVOC的排放还不确定。具体目标是：确定生长环境造成的城乡响应梯度，如T、[CO2]和[O3]；将痕量气体交换与物理和生物物理驱动因素(包括季节性)联系起来；提供足够的通量数据，以改进更大规模的异戊二烯响应和反馈模型。从休斯顿市中心到萨姆·休斯顿国家森林的四个地点，生物气象数据，以及[CO2]和[O3]将被全年记录。此外，还将收集有关小气候和土壤参数的辅助数据。将被研究的当地树木包括五种橡树、香椿和火炬松。沿研究地点的预期温度和二氧化碳梯度分别约为1K和20ppm。由本科生进行的受控实验室、分支机构的实验将补充现场数据。研究将由本科生和研究生进行。本科生将协助现场工作，并进行他们自己的实验室测量和分析。高中项目将让教师和学生参与研究，通过在我们部署扩大的气象站测量气候和空气质量梯度的同一学校启动相关的全球项目活动。教师和学生可以直接使用这些数据，生成自己的地球科学数据，并在实地测量和研讨会期间与研究人员互动。

The overarching objective is to investigate responses of biogenic volatile organic compound (BVOC) emissions to variations in climate parameters, such as temperature and humidity. BVOC emissions, particularly isoprene, exert an important direct influence on atmospheric chemistry and an indirect one on climate. Increased BVOC emissions in a warmer climate can exacerbate regional ozone pollution and reinforce global warming. However, future BVOC emissions are uncertain due to a lack of understanding of plant BVOC production and emissions' acclimatization to climate change. The specific objectives are to: determine urban-rural response gradients due to growth environment, such as T, [CO2], and [O3]; relate trace gas exchange to physical and biophysical drivers, including seasonality; and provide adequate flux data to improve isoprene response and feedback modeling on larger scales.Along four sites from central Houston to Sam Houston National Forest, biometeorological data, and [CO2] and [O3] will be recorded year-round. In addition, auxiliary data on microclimates and soil parameters will be collected. Local trees to be studied include five oak species, sweetgum, and loblolly pine. Expected temperature and CO2 gradients along the study sites are of order 1 K and 20 ppm, respectively. Controlled laboratory, branch-level experiments performed by undergraduate students will complement the field data. Research will be conducted by undergraduate and graduate students. Undergraduate students will assist with field, and perform their own laboratory measurements and analyses. The high school program will involve teachers and students in research through jump starting related GLOBE program activities at the same schools we deploy the expanded weather stations measuring the climate and air quality gradient. Teachers and students can work with these data directly, generate their own earth science data, and interact with researchers during field measurements and workshops.