§ Populyatsiya rivojlanishining modellari Populyatsiya

writeln ('Qadam j Vaqt t Soni N Tezligi v');
for j:=1 to i do if (j mod l) = 0 then
writeln(‘ ’,j,’ ‘,t[j]:6:3, ‘ ‘, N[j]:6:0,’ ‘ ,v[j]:6:0);
writeln(' ',i,' ',t[i]:6:3,' ', N[i]:6:0,' ',v[i]:6:0);
readln;
gD:=Detect; Initgraph(gD, gM, ' ');
setbkcolor(15); setcolor(1);
g0k:=20;
if z = 1 then v0k:=420;
if z = 2 then v0k:=300;
line(g0k, v0k, 620, v0k); outtextxy(620, v0k, 't');
line (615, v0k-5, 620, v0k); line (625, v0k-5, 620, v0k);
line (g0k, 20, g0k,470); outtextxy(g0k-10, 15, 'N/v');
line (g0k-5, 25, g0k, 20); line (g0k+5, 25, g0k,20);
bg:=50; bv:=50; ag:=1;
if z = 1 then av:=300:
if z = 2 then av:=250;
kg:=bg/ag; kv:=bv/av;
for j:=1 to 10 do line(g0k+j*bg, v0k-5, g0k+j*bg, v0k+5);
str(ag:3:0, ass); outtextxy(g0k+bg, v0k+5, ass);
for j:=1 to 10 do line(g0k-5, v0k- j*bv, g0k+5, v0k - j*bv);
for j:=1 to 5 do line(g0k-5, v0k + j*bv, g0k+5, v0k + j*bv);
str(av:2:0,ass); outtextxy(g0k-20,v0k-bv-10,ass);
if z=2 then
begin
as:=r/k; yk:= round (v0m – kv*as);
setcolor(4);
line (g0k, yk, 640, yk); {Asimtota }
end;
for j:=1 to i do
begin
tm:= round(g0k+kg*t[ j]);
Nm:= round (v0k-kv*N[j]);
vk:= round (v0k-kv*V[j]);
setcolor(2); circle(tk, Nk ,1);
setcolor (13); circle (tk, vk,1);
end;
setcolor(2);
outtextxy (tk-10,Nk-10 ,'N(t)');
setcolor(13);
outtextxy(tk-10,vk+10,'v(t)');
readkey;
closegraph;
end;
END.
Ushbu dastur matn rejimida aholi o'zgarishi modellarini jadval ko'rinishida quradi va Maltus modeli uchun (62-rasm) va Verxyulst modeli uchun (63-rasm) jadvallardagi qadam dasturda shunday tanlanadiki, modellashtirish natijalar tanlab oxirgi bilan birga ekranda taqdim etiladi. Maltus modeli uchun dastur har 50 qadamda jadval tuzdi va taxminan 10 vaqt birligida 900 qadamni amalga oshirdi; Verxyulst modeli uchun har 89 qadam, ularning barchasi 1785-jadvalda taxminan 18 vaqt birligida jadvalga kiritilgan.
Keyin bir xil natijalar Maltus modeli (65-rasm) va Verhulst modeli (66-rasm) uchun grafik tarzda chiziladi. Ushbu modellar (populiyatsiya soni o'zgarishi va uning tezligidagi o'zgarishlar) yuqorida keltirilgan xulosalarni aniqroq tasvirlaydi. 65-rasmda aholining 1000 kishining boshlang'ich qiymatidan 10 vaqt birligida taxminan 2700 tagacha o'sishi ko'rsatilgan, bunda sur'at asta-sekin o'sib boradi.

65-rasm - Maltusning jadval va grafik modellari

66-rasm - Verxyulstning jadval va grafik modellari
66-rasmdan ko'rinib turibdiki, populyatsiya birinchi navbatda 1000 kishidan 300 tagacha kamayadi va keyin barqarorlashadi.
Ushbu modellar bilan tajriba o'tkazish orqali siz populyatsiyadagi individlarning dastlabki soni va a, b, r va k koeffitsientlari stabilizatsiya davriga qanday ta'sir qilishini bilib olishingiz mumkin.