Sampling scale effects of vegetation apparent clumping index obtained by digital hemispherical photography

نویسندگان

چکیده

植被聚集指数CI(Clumping Indexï¼‰è¡¨å¾æ¤è¢«å† å±‚å¶ç‰‡çš„èšé›†ç¨‹åº¦ï¼Œæ˜¯å½±å“å† å±‚å† è¾å°„ä¼ è¾“çš„é‡è¦æ¤è¢«ç»“æž„å‚æ•°ï¼Œå¯¹æ›´å¥½åœ°ç†è§£å† å±‚çš„è¾å°„ä¼ è¾“å ·æœ‰é‡è¦æ„ä¹‰ã€‚æ•°å­—åŠçƒæ‘„å½±æ³•DHP(Digital Hemispherical Photography)与有限长度平均方法的结合被广泛应用于地面CIä¼°ç®—ï¼Œç ”ç©¶è¡¨æ˜Žï¼Œæœ‰é™é•¿åº¦å¹³å‡æ³•åº”ç”¨äºŽDHPå›¾åƒæ—¶æ‰€åˆ’åˆ†çš„é‡‡æ ·å•å ƒå¤§å°ä¸ŽCIæµ‹é‡ç»“æžœå¯†åˆ‡ç›¸å ³ï¼Œå³CIéšå›¾åƒé‡‡æ ·å°ºåº¦çš„å˜åŒ–ä¼šè¡¨çŽ°å‡ºæœ‰æ„ä¹‰çš„å˜åŒ–ï¼Œæ¤è¢«è¡¨è§‚èšé›†æŒ‡æ•°ACI(Apparent Clumping Index ï¼‰æ• åº”è¿è€Œç”Ÿï¼ŒACIçš„æå‡ºæœ‰åŠ©äºŽåŠ æ·±å¯¹æ¤è¢«èšé›†æ•ˆåº”çš„ç†è§£ï¼Œæ‹“å±•æ¤è¢«CI的地面间接测量,同时也对CI星载遥感产品的验证提出了新的挑战。目前,应用有限长度平均法估算ACI时,DHPå›¾åƒä¸­åˆ’åˆ†çš„é‡‡æ ƒçš„å¤§å°å¯¹ACIä¼°ç®—çš„å½±å“è§„å¾‹ï¼ŒåŠå ¶éšä¸åŒæ¤è¢«ç±»åž‹çš„å˜åŒ–è§„å¾‹æœ‰å¾ è¿›ä¸€æ­¥æŽ¢ç´¢ã€‚é’ˆå¯¹ä¸Šè¿°é—®é¢˜ï¼Œæœ¬ç ”ç©¶åŸºäºŽDHPå›¾åƒï¼Œåˆ†åˆ«ä»¥ä¸€ç³»åˆ—é€çº§å¢žå¤§çš„è§’åº¦é‡‡æ ·å°ºåº¦å¯¹è§‚æµ‹å¤©é¡¶è§’å’Œæ–¹ä½è§’è¿›è¡Œåˆ’åˆ†ï¼Œå ±å¾—åˆ°30ç§é‡‡æ ·æ–¹æ³•ã€17çº§è§’åº¦é‡‡æ ·åˆ†è¾¨çŽ‡ï¼Œå¹¶å°†å ¶åˆ†åˆ«åº”ç”¨äºŽæž—ã€çŒã€è‰å’Œå†œä½œç‰©å››ç§åœ°ç±»ï¼ŒæŽ¢ç©¶äº†ACI在不同植被类型下随17çº§è§’åº¦é‡‡æ ·åˆ†è¾¨çŽ‡å˜åŒ–è€Œå˜åŒ–çš„è§„å¾‹ï¼›åŒæ—¶ï¼ŒæŽ¢è®¨äº†ACIçš„è§’åº¦é‡‡æ ·å°ºåº¦æ•ˆåº”ä¸Žæ¤è¢«åœ¨ç©ºé—´ä¸­çš„åˆ†å¸ƒå½¢æ€ï¼Œä»¥åŠå†œä½œç‰©ç”Ÿé•¿é˜¶æ®µä¹‹é—´çš„å¯†åˆ‡è”ç³»ã€‚ç»“æžœè¡¨æ˜Žï¼Œåœ¨å››ç§åœ°ç±»ä¸‹ï¼Œéš17çº§è§’åº¦é‡‡æ ·åˆ†è¾¨çŽ‡çš„é™ä½ŽACI从约0.5变化至0.8ï¼Œå¹³å‡å¢žå¹ åˆ†åˆ«è¾¾åˆ°26%、29%、14%和35%;在大豆作物的不同生长阶段,随17çº§è§’åº¦é‡‡æ ·åˆ†è¾¨çŽ‡ç”±é«˜åˆ°ä½Žçš„å˜åŒ–ï¼ŒACIçš„å¢žé•¿å­˜åœ¨ä¸€å®šå·®å¼‚ï¼Œå¢žå¹ æœ€å¤§å¯è¾¾60%ã€‚æœ¬ç ”ç©¶é’ˆå¯¹CIåœ°é¢æµ‹é‡çš„ä¸ä¸€è‡´æ€§é—®é¢˜å±•å¼€ç ”ç©¶ï¼Œæ­ç¤ºäº†ACIè§’åº¦é‡‡æ ·å°ºåº¦æ•ˆåº”çš„æ–¹å‘ä¾èµ–æ€§è§„å¾‹ï¼Œæ€»ç»“äº†ä¸åŒæ¤è¢«ç±»åž‹ä¸‹è§’åº¦é‡‡æ ·å°ºåº¦å¯¹ACI估算结果影响的统一性和差异性,有望为CI遥感产品验证的不确定性分析提供地面测量数据变化的精细分析支撑。

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ژورنال

عنوان ژورنال: Journal of remote sensing

سال: 2023

ISSN: ['1007-4619', '2095-9494']

DOI: https://doi.org/10.11834/jrs.20221647