density of stand 中文意思是什麼
density of stand
解釋
林分密度-
According to the law of different forest stand can arise different forest fire, based on the existing forest distribution at the badaling forestry center, the area percentage of different forest types, forest age, crown density and slope for each sub - compartment were analyzed, and based on the different characteristics of each sub - compartment, some rational methods of fire prevention were put forward
摘要本論文基於不同的林分能引起不同的林火特性規律，針對北京八達嶺林場林分狀況，統計分析了各林班不同林分類型、林齡、郁閉度、坡度的面積分佈百分比，根據不同林班林分特點，提出了合理的營林防火措施。 -
Mongolica young stand, secondary natural forest, and the mixed forest of larix olgensis and fraxinus mandshurica rupr. countermeasures for controlling soil degradation were also recommended. the study got following results : ( 1 ) from young stand to mid - age of larix olgensis, with the closure of canopy and the decrease of undergrowth vegetation cover, soil acidity, enzyme activity, total inorganic phosphorus, available k, soil moisture and total porosity decreased significantly ; while soil organic matter content, humus component content, the amount of three main types of microbes, acid phosphatase activity, and bulk density in rhizosphere soil and non - rhizosphere soil increased with the increase of the amount of forest floor litter ; from mid - age stand to near mature stand, with the decrease of stand density and crown cover as well as the restoration of undergrowth vegetation after preliminary thinning, soil organic matter content, fulvic acid, exchangeable acidity, exchangeable aluminium, neutral phosphatase activity, total amount of inorganic phosphorus, the amount of actinomycetes, soil moisture, and total porosity in rhizosphere soil and non - rhizosphere soil apparently increased ; from near matu re stand to mature stand, soil activity acidity, organic matter content, humus component content, available phosphorus, total amount of amino acid, available k, soil enzyme activity, soil moisture, and total porosity in rhizosphere soil and non - rhizosphere soil decreased, but total phosphorus, soil acidity ( in particular, exchangeable aluminium ), and bulk density increased
結果表明： （ 1 ）從落葉松幼齡林到中齡林，隨著林冠的郁閉和林下植被蓋度的急劇下降，林地土壤酸度、土壤酶活性、無機磷總量、速效鉀、土壤水分含量、總孔隙度呈明顯下降趨勢，而根際和非根際土壤有機質含量、腐殖質各組分含量、三大類微生物數量、酸性磷酸酶活性和土壤容重隨著凋落物的增加呈明顯上升趨勢；從中齡林到近熟林，由於撫育間伐，林分密度及郁閉度下降，林下植被蓋度逐步得到恢復，根際與非根際土壤有機質含量、富里酸、交換性酸、交換性鋁、中性磷酸酶、無機磷總量、放線菌數量、土壤水分含量、總孔隙度呈明顯的上升趨勢；從近熟林到成熟林，隨著林齡的增大，根際與非根際土壤活性酸、有機質含量、腐殖質各組分含量、有效磷含量、氨基酸總量、速效鉀、土壤酶的活性、土壤水分含量和總孔隙度呈下降趨勢，而根際與非根際土壤全磷含量、土壤酸度（特別是交換性鋁）和容重呈增加趨勢。 -
Density structure and growth dynamics of larix principis - rupprechtii stand for water resource conservation in wutai mountain region in shanxi province
五臺山華北落葉松水源涵養林密度結構與生長動態 -
Study on the stand density of pinus massoniana
三明地區馬尾松人工林經營密度研究 -
The results showed that stem volume ( v ) and wood basic density ( bd ) were the most important traits in selection breeding for pulpwood of masson pine and, stand and individul selections shoud be based on the provenance selection
結果表明，馬尾松制漿造紙材的良種選育應以材積和木材基本密度作為主要指標，首先進行種源的選擇，在此基礎上進行林分和個體的選擇。 -
Impacts of stand density of first - rotation chinese fir on growth of 2 - year - old, second - rotation chinese fir plantations
第1茬林分密度對2茬2年生杉木林生長影響 -
The reduction of soil nutrient content and enzyme activity, and the apparent increase of soil acidity and bulk density are likely the main reason for soil degradation in mature stand
土壤養分和酶活性的降低以及土壤酸度和容重的顯著增加是成熟林土壤質量降低的主要原因。
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