李美君 杜慶 張克斌 劉小丹
(水土保持和荒漠化防治教育部重點實驗室(北京林業(yè)大學(xué)),北京,100083) (中國環(huán)境管理干部學(xué)院)
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北方農(nóng)牧交錯帶草地植被數(shù)量波動特征1)
——以寧夏鹽池縣為例
李美君杜慶張克斌劉小丹
(水土保持和荒漠化防治教育部重點實驗室(北京林業(yè)大學(xué)),北京,100083)(中國環(huán)境管理干部學(xué)院)
為了制定北方農(nóng)牧交錯帶草地植被恢復(fù)措施,以寧夏鹽池縣人工封育區(qū)為研究對象,調(diào)查了2010—2014年植被數(shù)量特征(蓋度、生物量、群落高度、密度),利用北方農(nóng)牧交錯帶草地植被波動測度公式進(jìn)行計算和分析。結(jié)果表明:(1)2010—2014年植被波動率變化范圍是-0.109~0.200,整體波動率的變化并不顯著,2012年的波動率為-0.109,是調(diào)查期內(nèi)草地植被生長狀況最差的年份,2010—2011年和2013—2014年呈現(xiàn)植被波動可逆性;(2)降水是影響研究區(qū)草地植被數(shù)量波動的重要生態(tài)因子,2010—2014年植被波動強度變化趨勢與降水趨勢大體一致,但是2012年植被波動的異常現(xiàn)象可能是受到了生物結(jié)皮的影響。
北方農(nóng)牧交錯帶;人工封育;草地植被;數(shù)量波動
In order to provide reference for the evaluation of the northern farming pastoral zone of grassland vegetation restoration measures, in the Yanchi County artificial enclosure, we investigated vegetation characteristic values including coverage, biomass, community height and density from 2010 to 2014 to calculate and analyze northern farming pastoral zone using the grassland vegetation fluctuation formula. In 2010-2014, vegetation fluctuation rate ranged in -0.109-0.200, and the overall fluctuation was not significant. The fluctuation rate in 2012 was -0.109 which was the worst year of grassland vegetation, and in 2010-2011 and 2013-2014 the vegetation fluctuations were reversible. The precipitation was an important factor to grassland vegetation quantitative fluctuation, the grassland vegetation fluctuation in 2010 to 2014 was consistent with early precipitation (April to June), but the abnormal phenomenon of vegetation fluctuation in 2012 might be affected by the biological crust.
植被波動是植被動態(tài)的一種表現(xiàn)形式,是植被動態(tài)學(xué)研究的重要內(nèi)容之一。很多學(xué)者對植被波動作出了相關(guān)定義,Barkman[1]將植被波動定義為在短時間或周期性的氣候或水分的影響下,植物群落數(shù)量特征值(如蓋度、生物量、群落密度等)出現(xiàn)逐年或逐季的變化。彭少麟[2]認(rèn)為植物群落的波動是由不同群落復(fù)合生態(tài)因子逐年的變化引起群落在固有的季節(jié)性變化和逐年變化上的差異,它不改變?nèi)郝涞目傮w物種組成結(jié)構(gòu)和群落性質(zhì)。……