植物枝叶结构特征对其滞留养殖场颗粒污染物的影响机理及反馈作用

With the rapid development and enlargement of animal feeding operations (AFOs) in Jilin province, which is the major national region of livestock production, air pollutants including particulate matter accumulated in the air and transported to the adjacent residential areas urgently need to be controlled. Vegetation barriers can effectively mitigate particulate matter emissions and purify the air. However, there is limitation on extending this application in AFOs because of the lack of knowledge in the selection of vegetation species and the design of barriers. This proposed project will focus on the characteristics of branches and leaves of typical trees or plants to study the mechanism and their effects on collecting particulates and reduce the transportation and dispersion of the particulate emitted from AFOs. The correlation among the speed and concentration of particulate matter in the air, the dust accumulated on and within the branches and leaves, the selection of dust collected, and the feature of the branches and leaves will be established. The major factors that branches and leaves can effectively trapping particles will be summarized. This proposed projects will also evaluate the capability of selected vegetation in controlling particulate matters from the aspects of the dust collected by the branches and leaves, particulate suspended in the air and their response on exposing to the air pollutants. The expected results will improve the knowledge of the dispersion, transportation and fate of particulate matter emitted from AFOs, supply basic information and help in the selection of vegetation species, which has great value for guiding the application study of establishing vegetation barriers around AFOs.

在国家畜牧业主产区吉林省，畜禽养殖密集发展生产规模不断扩大，养殖场急待解决其排放的空气污染物包括悬浮颗粒物在大气中累积和向毗邻区域扩散迁移的问题。植物可以有效降低颗粒污染物净化空气，因此根据养殖场排放的颗粒物性质和地域特征选择合适的植物物种，将对控制颗粒污染物起到重要的作用。本项目将从典型植物元素结构特征出发，对其拦截滞留养殖场空气颗粒物的作用机理进行研究，建立空气颗粒物浓度和速度、植物枝叶滞尘量、滞尘选择性与枝叶结构特征之间的关系，找到有效抑制颗粒物扩散迁移的植物枝叶特征要素，从植物滞尘、空气颗粒物和对植物对污染物抗逆性综合评估所选植物的滞尘能力，并通过悬浮颗粒物性质和植物长势分析植物对污染物的响应和反馈。研究结果将提高对养殖场颗粒物经植被隔离带扩散迁移与归趋规律的了解，为隔离带物种选择提供基础理论依据，对养殖场周边构建隔离带有效阻滞截留颗粒污染物的应用研究具有重要的指导意义。

在国家畜牧业主产区吉林省，畜禽养殖密集发展生产规模不断扩大，养殖场急待解决其排放的空气污染物包括悬浮颗粒物在大气中累积和向毗邻区域扩散迁移的问题。植物可以有效降低颗粒污染物净化空气，因此根据养殖场排放的颗粒物性质和地域特征选择合适的植物物种，将对控制颗粒污染物起到重要的作用。本项目对长春周边地区两处典型的畜禽养殖场（种鸡场和牛场）颗粒物浓度进行监测，分析其颗粒物排放特征规律，了解了典型畜禽舍颗粒污染物向周边环境扩散程度及其影响因素，为有效设置植被隔离带奠定基础。建立了空气颗粒污染物流经植被隔离带的流体计算模型，从动力学角度分析颗粒物随气流绕过和穿过植被隔离带的传递和沉降特征，对不同物理几何参数的隔离带及不同行间距情况下的隔离带滞尘效率进行了预测。通过风洞测试系统对枝-叶尺寸结构的丁香和樟子松植被拦截养殖场颗粒物源的效率进行了试验研究，从叶面微观结构、接触角、颗粒物沉积分布、含尘气流速度和颗粒物浓度等角度系统分析了两种植物在截留颗粒物的特征及效率。另外，在一典型机械通风式养鸡场排风口外建立了五种隔离带（卫矛、紫叶稠李、海棠、糖槭、山桃稠李），一方面对植被上下风向的颗粒污染物浓度变化进行监测和拦截效率分析，另一方面对植被的叶子等要素进行微观滞尘分析。建立空气颗粒物浓度、植物枝叶滞尘量、滞尘选择性与枝叶结构特征之间的关系，从植物滞尘和空气颗粒物综合评估所选植物的滞尘能力。在此项目资助下，已发表学术论文3篇，在审论文3篇；申请国家专利8项，其中授权国家发明专利4项、实用新型1项。培养硕博研究生共计4人，其中已经毕业硕士研究生和博士研究生各1人。全面完成项目的预期研究工作。