西北植物学报
西北植物學報
서북식물학보
ACTA BOTANICA BOREALI-OCCIDENTALIA SINICA
2004年
3期
370-383
,共14页
集合种群%空间混沌%Allee效应%拥挤效应%捕食效应%元胞自动机
集閤種群%空間混沌%Allee效應%擁擠效應%捕食效應%元胞自動機
집합충군%공간혼돈%Allee효응%옹제효응%포식효응%원포자동궤
metapopulation%spatial chaos%Allee effect%overcrowding effect%predation effect%cellular automata
集合种群的空间模式研究是当今生态学的核心问题之一.本研究利用常微分动力系统以及基于网格模型的元胞自动机模型对Allee效应、拥挤效应以及捕食作用集合种群的空间分布模式做了全面的模拟研究.Allee效应描述当种群水平低于某一阈值时会发生由生殖成功几率下降造成的种群负增长率,而拥挤效应是指当种群密度过高时引起的个体性为异常从而达到调节种群增长率的作用.文章组建了3个空间确定性模型:局部作用模型(CIM)、距离敏感模型(DSM)和集合种群捕食模型(MMP).局部作用模型显示在一维生境中空斑块形成金字塔状,二维模型显示出明显的动态拟周期性以及由空间混沌所形成的异质性.距离敏感模型可导致由迁移个体中密度制约强度决定的集合种群大小复杂动态与种群密度的双峰分布.这些结果说明动态行为的复杂性,不仅可用于表征研究物种的特性,而且可以表明该物种的续存能力与灭绝风险.集合种群捕食模型是概率转换空间模型,利用该模型得出了依赖于模型参数和生境尺度的自组织种群概率空间分布模式.模拟的结果表明,系统的内在机制和这种自组织模式导致捕食者形成集团型不明显的"捕食小组"或"杀手小组",并具有较高扩散力,但却包括侵占率低、灭绝率高的特点.而使猎物种群形成高集团性、高侵占率、低灭绝率、低扩散力的种群集团.这种特点又使捕食者种群在生境中处于中心地带,而使猎物种群形成在捕食者和生境边缘间的环状分布.这些结果还说明了尺度对于生态学的研究是至关重要的,不同的尺度将产生不同的系统模式.
集閤種群的空間模式研究是噹今生態學的覈心問題之一.本研究利用常微分動力繫統以及基于網格模型的元胞自動機模型對Allee效應、擁擠效應以及捕食作用集閤種群的空間分佈模式做瞭全麵的模擬研究.Allee效應描述噹種群水平低于某一閾值時會髮生由生殖成功幾率下降造成的種群負增長率,而擁擠效應是指噹種群密度過高時引起的箇體性為異常從而達到調節種群增長率的作用.文章組建瞭3箇空間確定性模型:跼部作用模型(CIM)、距離敏感模型(DSM)和集閤種群捕食模型(MMP).跼部作用模型顯示在一維生境中空斑塊形成金字塔狀,二維模型顯示齣明顯的動態擬週期性以及由空間混沌所形成的異質性.距離敏感模型可導緻由遷移箇體中密度製約彊度決定的集閤種群大小複雜動態與種群密度的雙峰分佈.這些結果說明動態行為的複雜性,不僅可用于錶徵研究物種的特性,而且可以錶明該物種的續存能力與滅絕風險.集閤種群捕食模型是概率轉換空間模型,利用該模型得齣瞭依賴于模型參數和生境呎度的自組織種群概率空間分佈模式.模擬的結果錶明,繫統的內在機製和這種自組織模式導緻捕食者形成集糰型不明顯的"捕食小組"或"殺手小組",併具有較高擴散力,但卻包括侵佔率低、滅絕率高的特點.而使獵物種群形成高集糰性、高侵佔率、低滅絕率、低擴散力的種群集糰.這種特點又使捕食者種群在生境中處于中心地帶,而使獵物種群形成在捕食者和生境邊緣間的環狀分佈.這些結果還說明瞭呎度對于生態學的研究是至關重要的,不同的呎度將產生不同的繫統模式.
집합충군적공간모식연구시당금생태학적핵심문제지일.본연구이용상미분동력계통이급기우망격모형적원포자동궤모형대Allee효응、옹제효응이급포식작용집합충군적공간분포모식주료전면적모의연구.Allee효응묘술당충군수평저우모일역치시회발생유생식성공궤솔하강조성적충군부증장솔,이옹제효응시지당충군밀도과고시인기적개체성위이상종이체도조절충군증장솔적작용.문장조건료3개공간학정성모형:국부작용모형(CIM)、거리민감모형(DSM)화집합충군포식모형(MMP).국부작용모형현시재일유생경중공반괴형성금자탑상,이유모형현시출명현적동태의주기성이급유공간혼돈소형성적이질성.거리민감모형가도치유천이개체중밀도제약강도결정적집합충군대소복잡동태여충군밀도적쌍봉분포.저사결과설명동태행위적복잡성,불부가용우표정연구물충적특성,이차가이표명해물충적속존능력여멸절풍험.집합충군포식모형시개솔전환공간모형,이용해모형득출료의뢰우모형삼수화생경척도적자조직충군개솔공간분포모식.모의적결과표명,계통적내재궤제화저충자조직모식도치포식자형성집단형불명현적"포식소조"혹"살수소조",병구유교고확산력,단각포괄침점솔저、멸절솔고적특점.이사작물충군형성고집단성、고침점솔、저멸절솔、저확산력적충군집단.저충특점우사포식자충군재생경중처우중심지대,이사작물충군형성재포식자화생경변연간적배상분포.저사결과환설명료척도대우생태학적연구시지관중요적,불동적척도장산생불동적계통모식.
Spatial pattern of metapopulation is one of the focuses of modem ecology.In this paper,I discuss and simulate the influences of Allee effect,overcrowding effect and predation effect on the spatial distribution of metapopulation by cellular automata based on lattice model and ordinary differential equations.The Allee effect indicates scarcity in reproductive opportunities that cause negative growth rates below a critical density threshold,which may arise from a number of sources such as difficulties in finding mates,social dysfunction and inbreeding depression.The overcrowding effect is a regulation of population growth by behavioral abnormalities caused by malfunction of the endocrine glands,which themselves occur in response to overcrowding.I constructed three spatially explicit models:local interaction model (CIM),distance-sensitive model (DSM) and metapopulation model with predation (MMP).The empty patches of CIM are pyramid-like in one-dimensional habitat;two-dimensional CIM shows a periodic phenomenon and the heterogeneity incurred by spatial chaos.Results of DSM show the overcrowding effect can lead to complex dynamics and bimodal distribution determined by the intensity of density dependence in immigrants.These results illustrate the complexity of dynamics can indicate not only the character of focal specie,but also the ability of persistence and the risk to extinction.MMP is a spatial probability transitional model and obtains a self-organization pattern of probability distribution.In order to comprehend the change of distribution pattern with parameters and scales,I simulated the model under different parameters and scales.The results show that the systematical internal mechanisms and the self-organization patterns lead to "predator group" or "killer group",with unobvious congeries and high diffusivity and low-level colonization and high-level extinction.In addition,this character makes the predator inhabit in the central zone,with prey population distributed between the edge and the center circularly.It also illustrates the important significance of scale in ecological researches,in which different scales can result in distinctive system patterns.