Journal of Geographical Sciences >
Characteristics of nonpoint source pollution load from crop farming in the context of livelihood diversification
Author: Shao Jing’an (1976-), Professor, specialized in regional environment evolution and climate responses.E-mail: shao_ja2003@sohu.com
Received date: 2017-03-11
Accepted date: 2017-05-05
Online published: 2018-03-30
Supported by
Chongqing University Innovation Team for 2016, No.CXTDX201601017
Chongqing Research Program of Basic Research and Frontier Technology, No.cstc2017jcyjBX0024
Copyright
Based on objective data collected from interviews in typical villages of the Three Gorges Reservoir Area, the present study devised three livelihood scenarios related to rural transformation development: agriculturally dominant livelihood, multiple-type livelihood and non-agriculturally dominant livelihood. Moreover, the present study reports the trend characteristics of nonpoint source pollution load of crop farming in relation to the transformation of dominant livelihood types, and discussed the primary factors which affect livelihood type transformations. Results indicated the following: (1) The current farmland pattern shows a trend of diversification as self-cultivation, cropland transfer and fallow in the sample region. Dynamic characteristics of cultivated land present a special feature that is more “transfer-into” than “transfer-out”. Various scales of planting are represented among the various households, according to the following decreasing order: half-labor household > non-labor household > adequate labor household. (2) The highest pollution loading produced by crop farming occurs in half-labor households while the lowest occurs in non-labor households. With increasing labor, the pollution load per unit area tends to first increase and then decrease within families with enough labor. (3) As the type of livelihood transitions from agriculturally dominant to non-agriculturally dominant, the maximum reduction of total pollution loading produced by the agricultural industry can reach 72.01%. Compared to agriculturally dominant livelihoods, multiple-type livelihoods produce a pollution load reduction yield of 19.61%-29.85%, and non-agriculturally dominant livelihoods reduce the pollution load yield by 35.20%-72.01%. However, the rate of reduction of total nitrogen is not the same as total phosphorus. (4) The non-agricultural characteristics of labor allocation and income promote the transformation from dominant livelihood types to non-agricultural livelihoods, while potential revenue conversion follows a similar trend. In addition, different household types do not display identical conversion rates, according to the following decreasing order: enough labor household > half-labor household > non-labor household. (5) During rapid urbanization and the building of new industrial systems, the livelihood types of rural households have been further transformed to off-farm household types in the mountainous region; this process will lead to the further reduction of pollution load generated by planting and agriculture. Hence, significant decreases in the planting pollution load necessitate the development of control measures to enhance transformations from agricultural to off-farm livelihoods.
SHAO Jing’an , HUANG Zhilin , DENG Hua . Characteristics of nonpoint source pollution load from crop farming in the context of livelihood diversification[J]. Journal of Geographical Sciences, 2018 , 28(4) : 459 -476 . DOI: 10.1007/s11442-018-1484-y
Figure 1 Location of the study site and distribution of the sampling villages |
Table 1 The situations of labor resource allocation among different ages (person) |
Age group (years old) | Labor resource allocation | |||||
---|---|---|---|---|---|---|
Migrant workers | Non-working people | Agricultural workers | Main migrant workers | Main agricultural workers | Total | |
<16 | 3 | 536 | 7 | — | — | 546 |
16-50 | 607 | 168 | 414 | 198 | 15 | 1402 |
50-65 | 25 | 23 | 427 | 45 | 9 | 529 |
>65 | 1 | 77 | 253 | 4 | 2 | 337 |
Total | 636 | 804 | 1101 | 247 | 26 | 2814 |
Table 2 The scenario classification of different farmer livelihood types |
Farmer livelihood scenario types | Major livelihood assets | Leading livelihood strategy | Land dependence degree | Land transfer intensity | Main farm household income |
---|---|---|---|---|---|
LH type 1 | Natural assets | Agriculture | High | Low | Agricultural products |
LH type 2 | Natural assets and human capital | Agriculture and sidelines | Relatively high | Relatively strong | Non-farm income and agricultural products |
LH type 3 | Human capital and social assets | No-agriculture | Low | Strong | Non-farm income |
Note: The meaning of farmer livelihood types is explained in the following page. |
Table 3 The value range of river load ratio of pollutants resulted by planting of different farmers |
Sampling site | TN value range | TN mean value | TP value range | TP mean value |
---|---|---|---|---|
Wushan | 0.0675-0.3902 | 0.1221 | 0.0401-0.2321 | 0.0726 |
Wulong | 0.0485-0.4906 | 0.1006 | 0.0289-0.2919 | 0.0598 |
Table 4 Farmland use of different household livelihood types and nonpoint source pollution load resulted by planting |
Household type | Labors per household (person) | Farmland area under actual cultivation* | Family- contracted farmland area* | Transferring into farmland area* | Transferring out farmland area * | Returning farmland area* | Abandoned farmland area* | TN** | TP** | Total load ** |
---|---|---|---|---|---|---|---|---|---|---|
HH type 1 | 1 | 9.02 | 17.93 | 1.11 | 2.16 | 6.69 | 1.17 | 35.70 | 18.02 | 53.72 |
2 | 6.44 | 9.77 | 1.18 | 0.73 | 3.05 | 0.72 | 34.15 | 19.30 | 53.45 | |
3 | 7.00 | 9.22 | 1.67 | 0.96 | 2.22 | 0.70 | 38.45 | 20.19 | 58.64 | |
4 | 4.72 | 7.96 | 1.18 | 0.85 | 3.00 | 0.55 | 35.69 | 21.70 | 57.39 | |
5 | 4.79 | 8.38 | 0.38 | 0.13 | 3.00 | 0.84 | 28.77 | 19.09 | 47.86 | |
HH type 2 | 1 | 10.43 | 25.16 | 1.52 | 4.16 | 9.72 | 2.36 | 33.02 | 23.06 | 56.08 |
2 | 11.34 | 22.55 | 1.81 | 1.57 | 9.82 | 1.64 | 37.53 | 23.40 | 60.92 | |
HH type 3 | - | 8.66 | 24.89 | 1.82 | 3.10 | 11.74 | 3.21 | 30.35 | 16.85 | 47.20 |
Mean value | - | 6.81 | 11.21 | 1.31 | 1.06 | 3.79 | 0.87 | 35.59 | 19.98 | 55.57 |
Note: * The unit is 10-2·hm2/person, and ** the unit is kg×hm-2. |
Figure 2 Pollution load per unit area of different farmer livelihood types^Note: The means of type 1, type 2 and type 3 are shown in the part of classification of peasant households. |
Figure 3 Pollution load per unit area among different main agricultural operating bodies^Note: The meanings of A, B, C, D, E and F are generally scattered households, big planting households, corporation, big breeding households, big planting and breeding households and cooperatives, respectively. |
Table 5 Nonpoint source pollution load resulted by planting among different farmer livelihood types |
Farmer livelihood types | Total load (t) | TN (t) | TP (t) |
---|---|---|---|
LH type 1 | 17.22-16.22 | 11.59-11.88 | 5.63-4.33 |
LH type 2 | 13.04-12.08 | 9.45-8.76 | 3.58-3.33 |
LH type 3 | 10.51-4.82 | 8.49-1.97 | 2.02-2.85 |
Table 6 The evolution characteristics of pollution load produced by planting in different farmer livelihood types, associating with the change of leading livelihood types |
Family type | Farmer livelihood type | Total load (t) | TN (t) | TP (t) |
---|---|---|---|---|
HH type 1 | LH type 1 | 14.46-13.63 | 9.73-9.98 | 4.73-3.64 |
LH type 2 | 11.09-10.29 | 8.04-7.45 | 3.05-2.84 | |
LH type 3 | 8.83-4.05 | 7.13-1.65 | 1.70-2.39 | |
HH type 2 | LH type 1 | 1.99-1.88 | 1.34-1.38 | 0.65-0.50 |
LH type 2 | 1.58-1.53 | 1.10-1.06 | 0.48-0.47 | |
LH type 3 | 1.22-0.56 | 0.98-0.23 | 0.23-0.33 | |
HH type 3 | LH type 1 | 0.76-0.71 | 0.51-0.52 | 0.25-0.19 |
LH type 2 | 0.56-0.46 | 0.44-0.37 | 0.11-0.09 | |
LH type 3 | 0.46-0.21 | 0.37-0.09 | 0.09-0.13 |
Figure 4 Employment structure of the labor resource |
Figure 5 Age structure of labor resource allocation |
Figure 6 Employment structure of the labor resource in the different farmer livelihood types |
Table 7 Labor resource allocation among different family types (person/household) |
Family type | Household’s labor (person) | Average people of every household* | Migrant workers* | Non-working people* | Agricultural workers* | Main migrant with agricultural workers* | Main agricultural with migrant workers* |
---|---|---|---|---|---|---|---|
HH type 1 | 1 | 2.95 | 0.61 | 0.48 | 1.55 | 0.29 | 0.01 |
2 | 4.66 | 0.97 | 1.57 | 1.65 | 0.40 | 0.06 | |
3 | 4.65 | 1.10 | 1.47 | 1.56 | 0.48 | 0.04 | |
4 | 5.52 | 2.01 | 1.49 | 1.48 | 0.52 | 0.01 | |
5 | 6.35 | 2.06 | 2.00 | 1.76 | 0.53 | — | |
HH type 2 | 1 | 1.73 | 0.03 | 0.16 | 1.35 | 0.14 | 0.05 |
2 | 2.11 | 0.05 | 0.20 | 1.75 | 0.11 | — | |
HH type 3 | — | 1.76 | 0.02 | 0.12 | 1.61 | — | — |
Mean value | — | 4.07 | 0.92 | 1.16 | 1.59 | 0.36 | 0.04 |
*Note: Their values are per household, and their units are person per household. |
Table 8 Income characteristics of different family types (yuan/person) |
Family type | Household’s labor (person) | Off-farm income* | Planting income* | Breeding income* | Subsidized income* | Total income* |
---|---|---|---|---|---|---|
HH type 1 | 1 | 6335.43 | 244.25 | 921.22 | 1248.00 | 8748.90 |
2 | 6565.66 | 579.68 | 700.35 | 681.03 | 8526.73 | |
3 | 7167.32 | 667.82 | 1246.90 | 438.14 | 9520.18 | |
4 | 8242.03 | 638.33 | 436.72 | 402.26 | 9719.34 | |
5 | 9952.04 | 669.19 | 655.09 | 255.39 | 11531.71 | |
HH type 2 | 1 | 1098.44 | 360.31 | 928.78 | 1501.07 | 3888.60 |
2 | 1347.46 | 348.56 | 1674.15 | 1547.25 | 4917.42 | |
HH type 3 | — | 523.60 | 305.22 | 759.58 | 1775.10 | 3363.50 |
Mean value | — | 6561.05 | 560.84 | 870.35 | 684.79 | 8677.01 |
*Note: Their values are per capita, and their units are yuan per capita. |
Figure 7 Source structure of different farmer livelihood types |
Figure 8 Per capita income of different employment |
Table 9 Farmers income accounting of different leading livelihood types (yuan/year) |
Farmer livelihood type | Type 1 | Type 2 | Type 3 | |||
---|---|---|---|---|---|---|
Per household | Per capita | Per household | Per capita | Per household | Per capita | |
LH type 1 | 9650.16 | 2099.66 | 7565.44 | 3865.86 | 4623.30 | 2632.71 |
LH type 2 | 55,906.36 | 12,164.00 | 7565.44 | 3865.86 | 4669.72 | 2659.14 |
LH type 3 | 58,935.70 | 12,823.12 | 13,930.70 | 7118.44 | 4669.72 | 2659.14 |
Figure 9 Labor structure of different farmer livelihood types |
The authors have declared that no competing interests exist.
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