【摘要】 本文计算分析了我国陆生植物在各种情况下的净初级生产力及其太阳能利用率。 计算表明,每年进入我国960万平方公里国土上的太阳总辐射Q和光合有效辐射PAR分别为13×10¹⁸千卡和6.4×10¹⁸千卡,其所含能量约合标准煤20,000亿吨和10,000亿吨。在充分利用我国光、温、水气候资源,而其他条件都处于最适状况时每年净初级气候潜力Y_ptw的全国总量为250亿吨（植物质干重,下同）。由植被产量的实际资料与气候因子的经验关系估算的自然植被产量Y_n的全国总量为每年70亿吨。 就全国加权平均单产而言,净初级光能潜力Y_p=87吨/公顷·年;净初级光温潜力Y_pt=50吨/公顷·年;净初级气候潜力Y_ptw=30吨/公顷·年;自然植被生产力Y_?=8吨/公顷·年;现阶段主要农作物的净初级实际生产力Y_α=8.7吨/公顷·年。各省区情况见表1。 太阳能利用率:就全国加权平均而言,如果把总辐射Q计为100％,则光合有效辐射PAR约占49％;具有最佳叶冠层的高产植物在生长盛期对Q的利用率上限为7％;相应于Y_p、Y_pt,Y_ptw和Y_n的太阳能利用率R_p、R_pt、R_ptw和R_n分别为2.5％,1.4％、0.82％和0.22％,我国当前主要农作物的净初级产量对我国农田上Q的利用率R_α为0.28％。各省区情况见表2。更多还原

【Abstract】 In this paper, the net primary productivity for land plants in China under different cases and the relevant utilization efficiency to solar energy are analyzed.Calculations indicate that the yearly sum of the global solar radiation Q and the photosynthetic active radiation (PAR) incident on the 9.6 million square kilometers of the land in China are respectively 13×1018 kcal and 6.4×1018 kcal, or about 2×1012 and 1×1012 metric tons of standard coal respectively.The yearly sum of the climatic potential net primary productivity, Yptw, which makes full use of PAR, temperature and precipitation when other conditions are optimum,is about 250 ×108 metric tons (dry weight).The yearly total of the estimated natural vegetation productivity Yn on the same land, which is dependent upon climatic factors, is about 70×108 metric tons (dry weight).W/ith regard to the weighted average of the net primary productivity in the whole land, the sunlight energy potential productivity, Yp, dependent on PAR when other conditions are optimum, is 87 ton·ha-1year-1; the sunlight-temperature potential productivity, Ypt, dependent on PAR and temperature when other conditions are optimum, is 50 ton·ha-1·year-1; the climatic potential productivity, Yptw is 30 ton·ha-1·year-1; the potential natural vegetation productivity, Yn, is 8 ton·ha-1 -year-1; the net primary productivity of the major crops at present, Ya, is 8.7 ton·ha-1·year-1 .The relevant values of each province and autonomous region in the country are given in the table 1 of this paper.According to the weighted average of Q and PAR in the whole country, if Q=100%, then PAR-49%;the upper limit of the solar energy utilization efficiency for high-producing varieties of plants with optimum leaf canopy and during the maximum growing season is 7 %; the solar energy utilization efficiency Rp, Rpt,Rptw,Rn and Ra--relevant to Yp, Ypt, Yptw, Y nand Ya--are respectively 2.5%, 1.4%, 0.82%, 0.22%, and 0.28% of Q (annual sum). The relevant values of each province and autonomous region are given in the table 2 of this paper.更多还原