露天煤矿煤粉沉降对矿区周边主要植物的生理影响

随着新疆准东煤田开采的日益加剧,露天开采及运输造成的煤粉尘不仅影响区域大气环境,同时在一定程度上影响周边植物的生理生长。为探讨煤粉尘对周边植物的生理影响,以准东露天煤矿周边人工绿化树种白榆、乡土植物梭梭和柽柳为研究对象,通过野外控制实验,探究覆尘、无尘条件下3种植物的光合生理特性的变化。结果表明:煤粉沉降对3种植物的光合生理均产生了明显影响,覆尘叶片在不同光照强度下净光合速率、气孔导度、蒸腾速率均降低,净光合速率柽柳(18.6%)梭梭(28.3%)白榆(30.7%),气孔导度梭梭(24.1%)柽柳(30.9%)白榆(33.2%),蒸腾速率梭梭(16.7%)白榆(18%)柽柳(39.1%);煤尘对白榆、梭梭的影响主要为非气孔因素,对柽柳的影响有待继续研究。因此露天煤矿开采造成的粉尘会在一定程度上影响周边植物的光合生理过程,抑制其生长,长期排放可能会导致植被覆盖度降低。

Effects of coal dust deposition on the physiological properties of plants in an open-pit coal mine

Open pit coal mining is the current source of substantial low-cost energy in China, but it has also caused major ecological and environmental issues. In the arid area of the East Junggar basin in Xinjiang, coal dust produced by open-pit mining not only affects the regional atmosphere, but also affects the physiological growth of nearby plants, to some extent. To determine the physiological effects of coal dust on surrounding plants, the Li-6400XT Portable Photosynthesis System was used to measure the photosynthetic parameters of Ulmus pumila L., Haloxylon ammodendron (C.A.Mey.) Bunge, and Tamarix chinensis Lour. under dust and dust-free conditions during the 2017 growing season. A field control trials was used to obtain light response curves for the three species in the vicinity of the coal mine. Plant samples were analyzed by scanning electron microscopy. Our major results were as follows: (1) Coal dust cover had an obvious effect on the three species. (2) Net photosynthetic rate, stomatal conductance, and transpiration rate of the coal-dust groups under different illumination intensities were reduced. Net photosynthetic rate in the coal-dust groups decreased from T. chinensis (18.6%) < H. ammodendron (28.3%) < U. pumila (30.7%). Stomatal conductance rates in the coal-dust groups decreased from H. ammodendron (24.1%) < T. chinensis (30.9%) < U. pumila (33.2%). Transpiration rates in the coal-dust groups decreased from H. ammodendron (16.7%) < U. pumila (18%) < T. chinensis (39.1%). (3) The influence of coal dust on U. pumila was mainly attributed to non-stomatal limitation, and the effects on H. ammodendron and T. chinensis should be examined further. Therefore, dust produced by open-pit coal mining affects the photosynthetic physiological processes of neighboring plants to some extent, thereby inhibiting plant growth, and long-term discharge may lead to a decrease in vegetation coverage.