北京林业大学学报
北京林業大學學報
북경임업대학학보
JOURNAL OF BEIJING FORESTRY UNIVERSITY
2015年
3期
101-110
,共10页
欧光龙%胥辉%王俊峰%肖义发%陈科屹%郑海妹
歐光龍%胥輝%王俊峰%肖義髮%陳科屹%鄭海妹
구광룡%서휘%왕준봉%초의발%진과흘%정해매
林分生物量%混合效应模型%环境因子%思茅松天然林
林分生物量%混閤效應模型%環境因子%思茅鬆天然林
림분생물량%혼합효응모형%배경인자%사모송천연림
stand biomass%mixed effect model%environmental factors%natural forest of Pinus kesiya var. langbianensis
本研究以云南省普洱市的思茅松天然林为对象,调查了3个位点45块样地的林分地上、根系和总生物量。以幂函数模型为基础构建林分生物量的基本模型;采用混合效应模型技术,考虑区域效应随机效应,选择基本混合效应模型,并分析模型的方差和协方差结构,分别构建3个维量的区域效应随机效应的混合效应模型;考虑林分因子、地形因子和气象因子固定效应,构建含环境因子固定效应和区域效应随机效应的林分生物量混合效应模型。所有模型均采用拟合指标和独立检验指标进行评价。结果表明:1)从模型拟合情况看,考虑区域效应的随机效应模型均能显著提高一般回归模型的精度;在3类含环境因子固定效应模型中,含地形因子固定效应的区域混合效应模型均具有最低的AIC和BIC值,表现最好;2)就模型独立性检验看,除地形因子固定效应的林分根系混合效应模型外,其余模型均优于一般回归模型;考虑环境因子固定效应的混合效应模型与普通区域效应混合模型相比,各个维量模型的独立性检验指标表现不一,但总体上差异不大;3)综合考虑模型拟合和独立性检验结果,除林分根系生物量选择普通区域效应混合模型外,另2个维量均选择含地形因子固定效应和区域效应随机效应的混合效应模型。
本研究以雲南省普洱市的思茅鬆天然林為對象,調查瞭3箇位點45塊樣地的林分地上、根繫和總生物量。以冪函數模型為基礎構建林分生物量的基本模型;採用混閤效應模型技術,攷慮區域效應隨機效應,選擇基本混閤效應模型,併分析模型的方差和協方差結構,分彆構建3箇維量的區域效應隨機效應的混閤效應模型;攷慮林分因子、地形因子和氣象因子固定效應,構建含環境因子固定效應和區域效應隨機效應的林分生物量混閤效應模型。所有模型均採用擬閤指標和獨立檢驗指標進行評價。結果錶明:1)從模型擬閤情況看,攷慮區域效應的隨機效應模型均能顯著提高一般迴歸模型的精度;在3類含環境因子固定效應模型中,含地形因子固定效應的區域混閤效應模型均具有最低的AIC和BIC值,錶現最好;2)就模型獨立性檢驗看,除地形因子固定效應的林分根繫混閤效應模型外,其餘模型均優于一般迴歸模型;攷慮環境因子固定效應的混閤效應模型與普通區域效應混閤模型相比,各箇維量模型的獨立性檢驗指標錶現不一,但總體上差異不大;3)綜閤攷慮模型擬閤和獨立性檢驗結果,除林分根繫生物量選擇普通區域效應混閤模型外,另2箇維量均選擇含地形因子固定效應和區域效應隨機效應的混閤效應模型。
본연구이운남성보이시적사모송천연림위대상,조사료3개위점45괴양지적림분지상、근계화총생물량。이멱함수모형위기출구건림분생물량적기본모형;채용혼합효응모형기술,고필구역효응수궤효응,선택기본혼합효응모형,병분석모형적방차화협방차결구,분별구건3개유량적구역효응수궤효응적혼합효응모형;고필림분인자、지형인자화기상인자고정효응,구건함배경인자고정효응화구역효응수궤효응적림분생물량혼합효응모형。소유모형균채용의합지표화독립검험지표진행평개。결과표명:1)종모형의합정황간,고필구역효응적수궤효응모형균능현저제고일반회귀모형적정도;재3류함배경인자고정효응모형중,함지형인자고정효응적구역혼합효응모형균구유최저적AIC화BIC치,표현최호;2)취모형독립성검험간,제지형인자고정효응적림분근계혼합효응모형외,기여모형균우우일반회귀모형;고필배경인자고정효응적혼합효응모형여보통구역효응혼합모형상비,각개유량모형적독립성검험지표표현불일,단총체상차이불대;3)종합고필모형의합화독립성검험결과,제림분근계생물량선택보통구역효응혼합모형외,령2개유량균선택함지형인자고정효응화구역효응수궤효응적혼합효응모형。
In this paper we took natural Simao pine ( Pinus kesiya var. langbianensis) forest as the research object, and investigated the aboveground, root and total biomass of 45 plots of at three typical sites ( Tongguan town of Mojiang County, Yunxian town of Simao District, and Nuofu town of Lancang County) in Pu'er City, Yunnan Province. Firstly, we chose the best power function to the basic model. Secondly, considering random effect of the regional effect we constructed the mixed effects models of the biomass components of stand using technology of mixed effects models, and analyzed the variance and covariance structures of the models. Finally, based on the basic mixed effects models of the components, We constructed the mixed effects models including fixed effects from three types of environmental factors (including stand, topographic and climate factors) respectively. The models were evaluated by fitting and independence test indices. The fitting indices include logLik, Akaike information criterion ( AIC ) and Bayesian information criterion ( BIC) , and the test indices include sum relative error ( SRE) , mean relative error ( MRE) , absolute mean relative error ( AMRE) and prediction precision ( p) . The results showed:(1) For the models fitting, the mixed model considering random effect of regional effect were significantly better than the ordinary models, and the mixed models including the fixed effect of environmental factors were better than the ordinary mixed models. Among the models including the fixed effects form three types of environmental factors, the models including topographic factors were the best models because of the lowest values for AIC and BIC. (2) For the independence test of models, except for the mixed models of stand root biomass including the fixed effects of topographic factors, the other mixed models were better than the ordinary models. Compared the mixed models including the fixed effect of environmental factors and the ordinary mixed models, the performance were different for three components, but for each component the differences among the models were small. (3) The best model for root biomass of stand was the mixed effects models only considering the random effect of regional effect, but for the other components ( including aboveground biomass and the total biomass of stand) , the best models were both the mixed effects models including the fixed effects of topographic factors and random effect of regional effect.