Figures 7.5 to 7.15 illustrate the percentage of farmers, by size category, within a given range of nitrogen nutrient balance. Following the discussion in Chapter 4, a range of -20 to -30, for example, indicates that farmers are creating an annual excess of 20 to 30 metric tons of nitrogen (for example) per hectare. The mass balance calculations performed here are used as rough estimates of actual nutrient balances. They serve to indicate households with potential problem areas, as well as where further research and technology transfer may be the more productive for certain size households. They also to serve to indicate why some households have active involvement with manure markets.
The mass balance for swine production showed a similar range of excess nitrogen and phosphorous across countries. Figures 7.5 to 7.7 shows nitrogen mass balance (i.e. land deficits, indicating nutrient loading) for swine production in Thailand, the Philippines, and Brazil, respectively. For each of the three countries in which the swine population was sampled, larger producers for the most part show larger deficits, indicating a greater need to find adequate disposal methods for manure. Each country has some households with sufficient land to assimilate nitrogen produced. Smaller producers are much more likely to have positive balances. Brazil, with its larger land availability, has households with positive balances in every size category. However, most of their large-scale producers do not have enough land to dispose of the manure based on the coefficients used in this analysis. Conversely, Thailand's large and medium-high producers all have large negative nutrient balances.
Figure 7.5 Nitrogen mass balance calculations for swine households surveyed in Thailand, 2002
Source: N. Poapongsakorn, et.al., Annex IV.
Figure 7.6 Nitrogen mass balance calculations for swine households surveyed in Brazil, 2002
Source: G.S. Camargo Barros, et.al., Annex V.
Figure 7.7 Nitrogen mass balance calculations for swine households surveyed in the Philippines, 2002
Source: A. Costales, et.al., Annex I.
Nutrient balances for broiler show wide variation between countries (see Figures 7.8-7.11). Large producers are likely to have large nutrient absorption deficits, while smaller producers are more likely to have small deficits. Small producers in Thailand (Figure 7.10) have the largest number of households with positive mass balances. Around 5 percent of Brazil's (Figure 7.11) small and medium producers could absorb manure in their own land. Both India (Figure 7.9) and the Philippines (Figure 7.8) show no households with a positive balance. This is indicative of the higher degree of households producing on relatively small plots of land. However, all of the Philippines broiler producers had a minimal excess of nitrogen nutrients from manure that they had to worry about disposal of up to 5 metric tons. For smaller production households with lower excess nutrient balances, informal mechanisms to dispose of manure may be sufficient as long as they meet environmental requirements. In all the countries surveyed there appears to be an active market for poultry manure to aid this. Large producers may require systems that guarantee that excess manure is disposed of in a controlled manner.
Figure 7.8 Nitrogen mass balance calculations for broiler households surveyed in India, 2002
Source: R. Mehta, et.al., Annex II.
Figure 7.9 Nitrogen mass balance calculations for broiler households surveyed in the Philippines, 2002
Source: A. Costales, et.al., Annex I.
Figure 7.10 Nitrogen mass balance calculations for broiler households surveyed in Thailand, 2002
Source: N. Poapongsakorn, et.al., Annex IV.
Figure 7.11 Nitrogen mass balance calculations for broiler households surveyed in the Brazil, 2002
Source: G.S. Camargo Barros, et.al., Annex V.
Relative to other livestock production, the mass balances for dairy production are comparatively in balance. Dairy production by its nature requires land. Thus producers, may have sufficient land to properly dispose of manure, or may have access to nearby land. It is possible that small-scale producers in place like India (Figure 7.12) or Thailand (Figure 7.13) may not warrant sophisticated manure disposal mechanisms if they have adequate land.
Figure 7.12 Nitrogen mass balance calculations for dairy households surveyed in India, 2002
Source: V.P. Sharma, et.al., Annex III.
Similar to broiler production, the mass balances for layer production show wide variation between countries (see Figures 7.14-7.15). Large producers are likely to have large nutrient absorption deficits, while smaller producers are more likely to have small deficits. No households in Thailand (Figure 7.14) or India (Figure 7.15) have a positive balance. However, the excess of small producers in both countries is relatively small. As with broilers, for smaller layer producing households with lower excess nutrient balances, informal mechanisms to dispose of manure may be sufficient as long as they meet environmental requirements. In all the countries surveyed there appears to be an active market for poultry manure to aid this. Large producers may require systems that guarantee that excess manure is disposed of in a controlled manner.
Figure 7.13 Nitrogen mass balance calculations for dairy households surveyed in Thailand, 2002
Source: N., Poapongsakorn, et.al., Annex IV.
Figure 7.14 Nitrogen mass balance calculations for layer households surveyed in India, 2002
Source: R. Mehta, et.al., Annex II.
Figure 7.15 Nitrogen mass balance calculations for layer households surveyed in Thailand, 2002
Source: N. Poapongsakorn, et.al., Annex IV.
