论思茅松林分系统的耗散结构特性

A Discussion on the Properties of Dissipative Structure of the Stand System of Pinus kesiya var. langbianensis

思茅松林分系统在地球上形成确定的地理分布区域, 其包含幼林、中林、成熟林、过熟林等许多林分,在各地位级上形成“正态分布”, 表达了林分系统与外界环境的和谐状态。外界环境是非均匀分布的“能量”和“物质”、即多样性的“立地环境”。因此思茅松的不同地位级、不同密度、不同年龄的许多林分, 与环境进行能量、物质交换的规律都表现为由幼林走向过熟林的多种“坐标序列”, 每一条“坐标序列”产生的净生长量, 都大于耗散掉的死亡量。不同“立地环境”、不同初始密度的林分, 由初始郁闭走向过熟林分的演变过程,都可以用y=A D±B的数学模型来描述, 它揭示出林分系统的“周期行为”; 进入过熟林分以后, 林分结构变为多个“世代”组成的“异龄林分结构”, 而各个“世代”发生的“株数递减/蓄积量递增”过程都不同。“世代更迭”的行为不遵守“时间倍增”规律, 而是更为复杂的自组织行为, 因此称为“非周期行为”。“周期行为”趋向复杂的“非周期行为”是一条演化通路, 表达出思茅松林分系统在时、空中的“物质流”。这种“物质流”必定是与外界环境的“能量流”进行能量、物质交换所产生出来的。

The System of Pinus kesiya var. langbianensis Stand has formed the definite geographically distributed area, including many types of stands such as young forest, half-mature forest , mature forest and over-mature forest, and the stands of the same type in different site class are normally distributed, which indicates that the system of the stands and the external environment are in a harmonious state. The external environment is heterogeneously distributed energy and matter, namely diversified site environment, so all the laws of many Pinus kesiya var.langbianensis Stands in different site class, different density and different age exchanging energy and matter with environment show the multiple coordinate sequences from young forest to over-mature forest,and the net growth yield produced by each coordinate sequence is more than the relevant dissipative death amount. All the succession processes from early crown closure to over-mature forest of the stands in different sites and different initial densities can be described by the mathematical model y=A^(±B), which reveals the periodic behavior of stands system. After the stand developed into over-mature forest, the stand structure became uneven-aged stand structure consisting of many generations. The process of the decrease in tree quantity and the increase in stand volume in each generation is different from others. The behavior of the alternation of generations of the stands, which is even more complex self-organization behavior, does not conform to the law of time multiplication, and thus called non-periodic behavior. Periodic behavior of the stands tends to become non-periodic behavior, which is a evolution route. It indicates the matter flow of the stand system of Pinus kesiya var.langbianensis in time and space. The matter flow must be produced in the way in which the stands exchange energy and matter with the energy flow of the external environment.