MAP Technical Reports Series No. 106 UNEP

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Table 13a
Estimated Total Nitrogen Load to Mediterranean Sea under 3 assumptions
of % diffused source load corrected for amount
fertilizer used /ha by countries
basic % assumption> Total estimated N-Load estimated
Population generated
actual
% point source 1
t/y F.f.
80%
t/y
60%
t/y
40%
t/y
Albania
France
Greece
Italy
Malta
Monaco
Spain
Yugoslavia
Sub-total
Algeria
Egypt
Libya
Morocco
Tunisia
Sub-total
Cyprus
Israel
Lebanon
Syria
Turkey
Sub-total
13,420
51,876
38,993
252,120
1,685
119
60,984
11,361
430,558
64%
50,600
72,648
10,050
14,916
21,846
170,060
25%
2,944
12,698
11,739
5,082
44,000
76,463
11%
1.23
2.70
1.45
1.49
0.54
0.00
0.66
1.06
0.24
3.13
0.07
0.27
0.15
0.40
1.74
1.04
0.31
0.51
47,647
367,855
158,987
1,054,547
3,213
71
132,982
35,787
1,801,090
67%
59,152
590,174
7,724
18,695
20,934
696,680
26%
4,558
60,607
36,484
6,798
80,183
188,630
7%
22,900
157,399
74,242
490,000
1,837
71
72,737
17,680
836,868
66%
41,157
248,559
6,665
12,604
16,043
325,027
26%
2,813
27,490
18,084
4,455
46,569
99,410
8%
14,651
87,247
45,994
301,818
1,378
71
52,656
11,645
515,461
66%
35,159
134,687
6,312
10,574
14,412
201,143
26%
2,231
16,450
11,950
3,674
35,364
69,670
9%
17%
8%
15%
14%
31%
100%
28%
19%
14%
51%
7%
78%
48%
63%
15%
39%
13%
19%
45%
33%
24%
35%
20%
32%
31%
55%
100%
50%
39%
31%
74%
18%
90%
71%
82%
31%
63%
28%
39%
68%
57%
46%
55%
36%
51%
50%
73%
100%
69%
59%
50%
86%
32%
96%
85%
91%
51%
79%
46%
59%
83%
75%
66%
Total t/ 677,081 2,686,400 1,261,305 786,274 15% 32% 52%
Total Load Estimate:
= 0.6*Pop-N* {1 + [basic %/(100 - basic %)]* F.factor}
1 Correspondingly: Actual % diffused load = 100 - % point source load
c) Estimates from river discharges
Good experimental river discharge estimates are difficult to achieve even under
favourable conditions. Meteo-climatic conditions play a major role: in dry years river loads may
be substantially below average, while in wet years major fractions of the total load may be
washed out during a few peak hydraulic discharge periods. Thus, in their study of the River Po,
Provini et al. (1992) found the phosphorus load in dry years to be as low as 7,000