许多科学家调查了松萎病发生和流行的规律。现已普遍认为松材线虫Bursaphelenchus xylophilus(Steiner et Buhrer)NickIe是该病的病原体。1971年Kiyohara和Tokushige用流行病学证实了松材线虫的致病力,并提出了引起松萎蔫病的一些其它因...许多科学家调查了松萎病发生和流行的规律。现已普遍认为松材线虫Bursaphelenchus xylophilus(Steiner et Buhrer)NickIe是该病的病原体。1971年Kiyohara和Tokushige用流行病学证实了松材线虫的致病力,并提出了引起松萎蔫病的一些其它因素,包括真菌和空气污染。目前,空气污染,特别是酸雨,是欧洲和北美一些国家引起森林衰退(Evans,1982;展开更多
In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern sub...In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern suburbs of Chongqing, China were studied. Based on the field data and measurements, a multivariable stepwise regression model was established to analyze the effects of multiple environmental factors on the productivity of the forest ecosystems. This model was used to assess the volume and economic losses of these two forest ecosystems caused by acidic deposition. The result showed that, among the environmental factors, pH value of precipitation, soil depth, soil organic contents and slope are the dominant ones influencing the growth of masson pine forest. It was also shown that the acidic deposition has no clear relation to the growth of C.Campora forest, so development of such broad leaved forest is suitable in the area.展开更多
文摘许多科学家调查了松萎病发生和流行的规律。现已普遍认为松材线虫Bursaphelenchus xylophilus(Steiner et Buhrer)NickIe是该病的病原体。1971年Kiyohara和Tokushige用流行病学证实了松材线虫的致病力,并提出了引起松萎蔫病的一些其它因素,包括真菌和空气污染。目前,空气污染,特别是酸雨,是欧洲和北美一些国家引起森林衰退(Evans,1982;
文摘In accordance with principles and methods of ecology, the effects of acidic deposition on productivity and volume increment of masson pine and Cinnamomum campora forest which are widely distributed in southern suburbs of Chongqing, China were studied. Based on the field data and measurements, a multivariable stepwise regression model was established to analyze the effects of multiple environmental factors on the productivity of the forest ecosystems. This model was used to assess the volume and economic losses of these two forest ecosystems caused by acidic deposition. The result showed that, among the environmental factors, pH value of precipitation, soil depth, soil organic contents and slope are the dominant ones influencing the growth of masson pine forest. It was also shown that the acidic deposition has no clear relation to the growth of C.Campora forest, so development of such broad leaved forest is suitable in the area.
